Electroweak Interactions & Unified Theories · 2016. 3. 29. · MoriondEW, Mar 19, 2016 Experimental Summary 51st Rencontre de Moriond Electroweak Interactions & Unified Theories

MoriondEW, Mar 19, 2016 Experimental Summary

51st Rencontre de Moriond

Electroweak Interactions & Unified Theories

— Experimental Summary —

Andreas Hoecker (CERN)

La Thuile, 19 March 2016


This Moriond EW & UT conference featured — as is tradition — a vibrant snapshot of newest results and trends in the fields of neutrino physics, astrophysics & cosmology, gravitational waves (!), dark matter and collider physics (it became the promised LHC feast).

Beautifully prepared talks! 53 on experimental results. We live in data-driven times.

I also found the YSF talks very interesting and well prepared.

Many thanks, indeed, to all the speakers!

Attempt for a summary …


Warning: in case you are asked next time, consider :

You won’t have this:


Warning: in case you are asked next time, consider :

You won’t have this:

But rather…


Views from a hotel room…

Wednesday, Mar 16: great Friday, Mar 18: bad


Neutrino physics

Another Nobel Price*for particle physics in 2015, and another one for neutrino oscillation !

Fluxed of 8B solar neutrinos measured by SNO and SK

-0.8 -0.4 0 0.4 0.80

200

-0.8 -0.4 0 0.4 0.8

multi-GeV e-like

cosΘ

multi-GeV μ-like + PC

cosΘ

Zenith angle distribution in SK for e-like and μ-like events above 1.35 GeV. Boxes show expectation without oscillation

*Awarded jointly to T. Kajita and A.B. McDonald


Neutrino physics

What do we know

Neutrinos are massive fermions

Three active neutrino flavours

Neutrino mass eigenstates are mixed flavour states, governed by PMNS matrix

Critical questions:

Neutrino nature: Majorana fermions?

Δm2 (2.5%) and angles (3–7%) pretty well known

Neutrino masses: absolute values & hierarchy

CP violation in neutrino sector (δCP in flavour-changing PMNS elements)

Are there sterile neutrinos, can we observe heavy additional neutrinos ?

But also: neutrino cross section and flux measurements and predictions


Neutrino physics

The tools

Neutrino oscillation measurements (short / long baseline)

Single beta decay

Neutrinoless double beta decay

Cosmology (Graziano Rossi: Σm < 0.12 eV with Ly- , CMB, BAO combined)

And also neutrinos as messengers in astronomy, Sun & geo science, as well as for GUT, lepto/baryogenesis and physics beyond the SM


Neutrinos from short-baseline accelerators: MicroBooNE170 ton LAr TPC neutrino experiment at FNAL that started data taking in October 2015

~500m from BNB ~ μ beam, dedicated to low-energy neutrino cross sections to investigate the excess seen by MiniBooNE in μ → e (and anti-…) appearance

Also step towards kiloton LAr TPC: DUNE (far detector) at LBNF (up to 2.4 MW beam power)

Principle: charged particle interacts with Ar: wire planes detect drifting ionisation electrons (→ tracks), PMTs detect scintillation light, use dE/dx to separate between e/γ

Eve

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0.5

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μ from eν+/- from Keν0 from Keν

misid0π

γ N→ Δ

dirtotherConstr. Syst. Error

Neutrino

(GeV)QEνE

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0.0

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0.6

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1.0

1.2 Antineutrino

3.01.5

MiniBooNE, PRL 110, 161801 (2013)

~3σ excess of electron-like events in Cherenkov detector

Electrons or photons ?

There is also the LSND anti- e excess

MicroBooNE event display

Sarah Lockwitz


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8

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Simulation

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P.O.T.)20 10×Absolutely normalized (3.49 Data: inner errors statistical

Simulation: statistical errors only

Neutrinos from short-baseline accelerators: MINERvADetailed study of neutrino interactions in varying nuclear targets (C, Pb, Fe, H2O)

For example, e CCQE is oscillation signal, but little low-energy cross-section data available. Can μ → e cross-sections be trusted universally ?

Exclusive measurement of flux-integrated differential cross section for e CCQE-like interactions

Sufficiently good description for current experiments

Next steps: higher beam E

e n → e– p (dominant) and e p → e+ n in hydrocarbon target

Non-magnetic tracking volume

Daniel Rutherbories

at NuMI, ~1km after NuMI target, 3.1 GeV peak μ energy (low-energy beam flux).

Detector features charged particle and em & had energy reconstruction, PID, uses MINOS (ND) as μ spectrometer

Test and improve –N interactions modelling


Long-baseline neutrino experimentsExtremely rich present and future long-baseline neutrino programme

DUNE LAr-TPC far detectorat 1.5 km level4 modules, 10 kton each Initial 1.2 MW beam (cf. 700 kW NuMI for Nova)

T2K beamline

look at μ disappearance and μ → e appearance + their anti processes

Probabilities depend on sin2(2θ13), well measured and large, on sin2(θ23), on δCP (→ CP violation), and on the sign of Δm2

31 (→ mass hierarchy)

→ All these properties can be experimentally addressed

Tokai to Kamioka (T2K) long-baseline experiment


Long-baseline neutrino experiments: MINOSND 24 ton, ~1 km on target; FD 4.2 kton (ND+FD magnetised), 735 km in Soudan mine, 705 m deep

released in May 2014 a combined analysis of μ disappearance and μ → e appearance data

Talk this week reported search for sterile neutrino using μ beam: 1 sterile introduces 6 new parameters. For simplicity set CP phases and θ14 = 0, fit: Δm2

32, Δm241, θ23, θ24, θ34

Ashley Timmons

0.2

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2 eV-3 = 2.37 x10322mΔ

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0 1 2 3 4 55 10 15 2020 3030 40

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0.1

0.2

0.3

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Systematic uncertainty

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MINOS Preliminary

MINOS data 90% C.L.

MINOS data 95% C.L.

Super-K 90% C.L.

CDHS 90% C.L.

CCFR 90% C.L.

SciBooNE + MiniBooNE 90% C.L.

active – sterile mixing may affect ND reference.Thus: combined fit of FD / ND ratio. Find agreement with 3-flavour model → limits


Reconstructed Neutrino Energy (GeV)0 1 2 3 4 5

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50 DataUnoscillated predictionBest fit prediction (no systs)

syst. rangeσExpected 1-

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AνNOT2K 2014MINOS 2014

Long-baseline neutrino experiments: NOvA14 kton FD (810 km, on surface), 0.3 kton ND, both are fine-grained tracking calorimeters

~0.8º off-axis from the NuMI beam → narrow E( μ) ~ 2 GeV, ~maximum of μ disappearance and e appearance, e ID

First results using 11/2014–6/2015 data (< 500 kW beam power):

e cross-section (a bit higher than T2K & Gargamelle → GENIE)

μ disappearance gives first measurement of Δm232 and sin2θ23:

Also first μ → e appearance result: 6/11 (LID/LEM) events observed in FD for ~1 expected background event (based on ND measurement). 3.3/5.3σ excess, LEM result less compatible with inverted hierarchy

With magnetic horns focusing on positive mesons NuMI beam composed of 97.6% μ, 1.7% anti- μ, 0.7 e + anti- e for neutrino energies between 1 and 3 GeV.

Beautifully simple detector technology

Jeff Hartnell


Long-baseline neutrino experiments: T2K295 km baseline, far detector SK (water), near detectors INGRIDon / ND280off (different target materials)

2.5º off beam axis giving narrow E( μ) ~ 0.6 GeV. ND280 target so far carbon, not same as SK

[ Combined μ → μ / e analysis (2010–2013, !2011 data) provided world’s best Δm232, θ23 measurements ]

Christine Nielsen

Anti- μ mode during Run 5–6 (2014/15): 11×1020 POT (cf. NOvA: 2.7×1020), 390 kW max beam power

Larger wrong-sign background, must measure in near detector: ~10% flux and cross-section uncertainties: improve by combined fit of model together with external and ND280 data as input to oscillation fit

→ Anti- μ disappearance: 34 μ events observed. Anti- e appearance: 3 events seen, not yet significant

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90% CLνT2K 68% CLνT2K 90% CLνT2K

90% CLνMINOS 90% CLνSuper-K

best fitνT2K best fitνT2K

best fitνMINOS best fitνSuper-K

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Clear evidence of oscillation in anti-μ disappearance


Long-baseline neutrino experiments: OPERABreakthrough in July 2015 with > 5σ observation of tau neutrino appearance (5 τ candidates)

exploits 732 km (2.5 ms) CNGS μ beam to search for τ appearance

Charged-current neutrino interactions are recorded in detectors (bricks) of lead and emulsion film with sub-micron resolution. Total target of 150k bricks. Additional target trackers & muon spectrometers.

Data between 2008 and 2012 were analysed, corresponding to 18×1019 POT giving 20k neutrino interactions in detector (6.7k analysed)

Event display of 5thτ candidate in emulsion

ChannelExpected background

Expected signal ObservedCharm Had. reinterac. Large μ scat. Total

τ → 1h 0.017± 0.003 0.022± 0.006 0.04± 0.01 0.52± 0.10 3τ → 3h 0.17± 0.03 0.003± 0.001 0.17± 0.03 0.73± 0.14 1τ → μ 0.004± 0.001 0.0002± 0.0001 0.004± 0.001 0.61± 0.12 1τ → e 0.03± 0.01 0.03± 0.01 0.78± 0.16 0Total 0.22± 0.04 0.02± 0.01 0.0002± 0.0001 0.25± 0.05 2.64± 0.53 5

( μ →) τ + N → τ – (→ e,μ,h) + X

Search track with large IP from τ decay,and no μ from PV

→ 5.1σ

Alessandra Pastore

Also limits on sterile neutrinos


Short-baseline (reactor) neutrino experiments: Daya BayPowerful anti- e source from ß-decay of reactor fission products, detector now completed

measures θ13 from anti- e survival probability O(km) away from reactors, dominated by Δm2

32 term

Detection through anti- e + p → e+ + n reaction (IBD) in Gd doped liquid scintillators. Prompt e+ annihilation γ+ delayed 8 MeV γ’s from neutron capture. Flux uncertainty eliminated by measuring at 3 different detector sites

→ sin2(2θ13) =0.084 ± 0.005 (10/2012–11/2013 data, 2/3rd 8 ADs)

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Daya Bay: 621 days

99.7% C.L.

95.5% C.L.

68.3% C.L.

Best fit

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1015

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T2K

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0.9

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Yiming Zhang

May 2015

Layout of China-based Daya Bay experiment

Two near (effective baselines 512 m and 561 m) and one far (1.6 km) experimental area

17.4 GW total thermal power


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Daya Bay: 621 days

Short-baseline (reactor) neutrino experiments: Daya BayPowerful anti- e source from ß-decay of reactor fission products, detector now completed

measures θ13 from anti- e survival probability O(km) away from reactors, dominated by Δm2

32 term

Detection through anti- e + p → e+ + n reaction (IBD) in Gd doped liquid scintillators. Prompt e+ annihilation γ+ delayed 8 MeV γ’s from neutron capture. Flux uncertainty eliminated by measuring at 3 different detector sites

→ sin2(2θ13) =0.084 ± 0.005 (10/2012–11/2013 data, 2/3rd 8 ADs)

Layout of China-based Daya Bay experiment



Yiming Zhang

Brand new analysis using neutrons captured by hydrogen (instead of gadolinium). Independent data sample, different systematics

→ sin2(2θ13) =0.071 ± 0.011 (nH)

→ sin2(2θ13) =0.082 ± 0.004 (nGd & nH combined)


Short-baseline (reactor) neutrino experiments: Double ChoozMulti-detector setup with ND (0.4 km, since 2015) & FD (1.1 km, since 2011)

New preliminary Double Chooz θ13 measurement with multi-detectors. Nearly iso-flux setup reduces flux uncertainty to < 0.1%. Uncorrelated detection systematic < 0.3%

Combined fit of parameters to FD-I, FD-II, ND data (reactor-off data also used for bkg constraint)

Layout of France based Double Chooz experiment



Masaki Ishitsuka

1322sin0 0.05 0.1 0.15 0.2 0.25

Double Chooz

Daya Bay

RENO

T2KCPArbitrary

JHEP 1410, 086 (2014)

PRL 115, 111802 (2015)

Preliminary (arXiv:1511.05849)

PRD 91, 072010 (2015) > 02

32 m

< 0232 m

Preliminary (Moriond)

→ sin2(2θ13) =0.111 ± 0.018 (stat + syst, 5.8σ from zero)


A word on reactor flux anomaliesCannot currently follow-up new physics claims based on absolute reactor flux comparisons

reports recent measurement of anti- e flux using 340k candidates, better than 1% energy calibration, and comparison with model prediction: ~2.5σ overall deviation, ~4σ local deviation at E( e) ~ 5 MeV (shown to be due to reactor ). While an overall deficit may look like disappearance to sterile neutrino, the bump does not!

Consistent with “reactor neutrino anomaly” picture from earlier short baseline measurements (Daya Bay, Reno, Double Chooz): measured / expected anti- e flux ~ 0.94

Anna Hayes explained us that much caution is needed as various uncertainties may in total cover the deficit.

The ~5 MeV bump may be due to prominent fission daughter isotopes (eg, 238U or Plutonium)

In any case, new experiments needed: ~10 very-short baseline experimental projects, among which: SoLid →

En

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50 k

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10000

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Prompt energy spectrum, Daya Bay,1508.04233, Aug 2015

Red prediction based on Hubert-Müller model, normalised to data

Prompt Energy (MeV)2 4 6 8 1

3 ton SoLid experiment deployed 5.5 m from the BR2 reactor core

Anna Hayes, Nick van Remortel


Prompt Event Energy [p.e.]500 1000 1500 2000 2500 3000 3500

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n

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22 Data

Reactor neutrino

Best-fit U+Th with fixed chondritic ratio

U fit with free chondritic ratio

Th fit with free chondritic ratio

Neutrinos from the Sun: Borexino (LNGS)New measurements after the 2014 breakthrough evidence for primary pp fusion neutrinos

initially designed for measurement of 0.86 MeV Be-7 solar e’s via -e scattering and electron recoil measurement (also IBD)

270 t liquid scintillator, surrounded by 890 t buffer fluid; Installed in 9.5 m diameter nylon vessel, 1.3km underground

Extremely high radiopurity allows 250 keV threshold

Sandra Zavatarelli

“Money” plot published in 2014. Resulting pp neutrino flux consistent with photon luminosity within 10% precision

Since that measurement Borexino focused on:

Detection (proof) of “CNO” cycle in Sun

Tests of e-charge conservation (e → γ , ), giving τe > 6.6×1028 years

Detection of geo-anti- e (largest bkg reactors)

5.9σ observation

Syntheticpile-up

7Be

210Po CNO 85Kr

210Bi

pep 214Pb

Energy (keV)150 200 250 300 350 400 450 500 550

10–5

10–4

10–3

10–2

10–1

1

10

102

103

104

2/d.o.f. = 172.3/147

pp : 144 ± 13 (free) 210Po: 583 ± 2 (free)7Be : 46.2 ± 2.1 (constrained) 14C: 39.8 ± 0.9 (constrained)pep : 2.8 (fixed) Pile-up: 321 ± 7 (constrained) CNO : 5.36 (fixed) 210Bi: 27 ± 8 (free)214Pb: 0.06 (fixed) 85Kr: 1 ± 9 (free)

a

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per

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measured over 11 orders of magnitude, but highest energy sources not well known

Neutrino astronomy with IceCubeIceCube studies astrophysical neutrino properties (and through atmospheric neutrinos also oscillation phenomena)

Neutrinos point back to their sources:

1.5–2.5 km deep in South Pole ice~1 km3 active volume in 86 stringsMeasures Cherenkov light”track” and “cascade” signatures~100k detected neutrinos / year (> 200 GeV) among which a few dozens astrophysical

TeV-scale muon (“track”) neutrino event superimposed on view of IceCube Lab

Jan Auffenberg

Characteristic signatures:

Direction ☺Energy res

Direction Energy res ☺

Direction ☺Energy res ☺

Large atmospheric μ and μ backgrounds


Energy spectrum > 60 TeV after 4 years of data53 good events, up to ~2 PeV, 6.5σ signalHard spectrum. E –2 model may be too simple

Neutrino astronomy with IceCubeHighest energy neutrinos have lowest atmospheric neutrino background

IceCube Preliminary

PoS (ICRC2015) 1081

IceCube also sees 5.9σ excess of up-going μ (CC only) 0.2–8.3 PeV energy over atmospheric background (normalised at 100 TeV)

Possible pattern in spectral index vs energy

No significant point source

Jan Auffenberg

beheric neutrino background

C only) 0.2–8.3 PeV energy over atmospheric

Jan Auffenberg

PoS (ICRC2015) 1081

No significant clustering found

Shower-like events are marked with + and those containing tracks with ×


Neutrino astronomy with IceCubeFlavour decomposition

Measurement of neutrino flavour can give hints about source of astrophysical neutrinos

Pion decay should produce e : μ: τ = 1 : 1 : 1 (at earth)

If muons suppressed (eg, due to large Bfields): 1 : 1.8 : 1.8 (earth)

If from neutron decay: 2.5 : 1 : 1 (earth)

But: no hint for (“double-bang”) tau neutrinos yet

Interesting, but insufficient data yet

→ Next generation IceCube-Gen2: ~10 km3 (R&D)

Jan Auffenberg, Gwenhae l de Wasseige

IceCube also now belongs to elite of experiments who have observed oscillation through μ disappearance: compatible Δm2

32, θ23 measurements

Also search for sterile neutrinos, heavy WIMP annihilation, solar flares


Of which quantum nature are neutrinos ?Search for neutrinoless double beta decay (0 ββ) in 136Xe (EXO200) and 130Te (CUORE)

Γ0 ββ |M0 ββ|2 m2ββ→ observation would indicate:

Non-zero Majorana mass term( Heavy right-handed N might be responsible )Infer information on mass & hierarchy (theory input)

Experiments require: • large mass • high isotopic abundance • good energy resolution • high efficiency • low background

2 ββ 0 ββ (LFV)

Paolo Gorla, Yung-Ruey Yen


Of which quantum nature are neutrinos ?Search for neutrinoless double beta decay (0 ββ) in 136Xe (EXO200) and 130Te (CUORE)

Γ0 ββ |M0 ββ|2 m2ββ→ observation would indicate:

Non-zero Majorana mass term( Heavy right-handed N might be responsible )Infer information on mass & hierarchy (theory input)


2 ββ 0 ββ (LFV)

Paolo Gorla, Yung-Ruey Yen

enriched (~81%) liquid-Xe TPC (136Xe → 136Ba + 2e–) installed in nuclear waste isolation plant in New Mexico, US.

bolometric technique using array of tellurium dioxide crystals (130Te → 130Xe + 2e–) cooled to ~10 mK! Good E resolution, no PID

Reconstructed Energy (keV)2470 2480 2490 2500 2510 2520 2530 2540 2550 2560 2570

Eve

nts

/ (2

keV

)

0

2

4

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10

12

14

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4−2−024

Qßß value (2528 keV)

9.8 kg·yr 130Te exposure

CUORE-0 + Cuoricino: <mββ> < (270–650) meV

2014 result using 100 kg·yr: <mββ> < (190–470) meV

Presented here new search for 2 ββ to excited 136Ba, which de-excites via 2 γ’s → MV analysis


Nucleon decay — GUT messengers

Cannot reach expected GUT energy in Lab. Even Enrico Fermi’s Globatron(that was to be built in 1994) would with LHC technology “only” reach 20,000 TeV CM energy


Messengers from GUT: baryon decayRemember: KamiokaNDE stands for Kamioka Nucleon Decay Experiment

presented new proton decay limits combining all SK I–IV data (1996–now)

Volodymyr Takhistov

No significant excess found, strong new limits:

τ(p → e+ π0) > 1.7 × 1034 years(no events seen in R1/2, 0.07/0.54 expected)

τ(p → μ+ π0) > 7.8 × 1033 years

(less sensitive because μ+ through decay to e+,0/2 events seen in R1/2, 0.05/0.82 expected, two events background like properties)

τ(p → K+ ) > 6.6 × 1033 years (K+ below Ch. threshold, detect through decays,no events seen in SB/C, 0.39/0.56 expected)

p → μ+ π0

p → e+ π0

Looked also for more exotic phenomena.

Order of magnitude sensitivity gain on p → e+ π0 expected from Hyper-K


Direct Dark Matter Searches

DirectDetection

(DM collision nuclear recoils)

Effective scattering Lagrangian may have scalar (SI A2) or axial-vector (SD nuclear spin, no coherence) terms

Dominant background from electrons recoiling after X-ray or γ-ray interactions


Direct Dark Matter Searches

Similar experimental challenges as for the elusive neutrinos

Deep underground

Excellent radio-purity

Shielding around active volume

Redundancy in signal detection


Direct dark matter searches: CDMSliteHigh bias voltage signal amplification to gain sensitivity to lower WIMP masses

looks for keV-scale recoils from elastic scattering of WIMPs off target nuclei. Uses up to 19 Ge and 11 Si detectors placed in Soudan mine. Ionisation charges & phonons (heat) are measured and used to discriminate electron (ER*) from nuclear recoils (NR).

CDMSlite: operate 1 Ge detector at higher bias voltage to amplify the phonon signal.

Two runs. Second run had reduced acoustic noise (→ lower threshold) and increase exposure

CDMSlite

*ER from Compton scatters due to radioactive detector components, intrinsic ß decays, solar scattering off electrons

Elias Lopez Asamar

New parameter space excluded between 1.6–5.5 GeV DM mass

SuperCDMS now ended. Follow-up programme: SuperCDMS SNOLAB (2.1 km deep)

Exclusion limit assumes all events in signal region are WIMPs


Direct dark matter searches: CRESST–IIImproved sensitivity to low-mass WIMPs: threshold is key

at LNGS uses cryogenic calcium tungstate (CaWO4) crystals to measure scintillation light and phonons to separate ERs from NRs. TES (~15 mK) and SQUID signal measurement & amplification.

Sub-keV energy thresholds and a high-precision energy reconstruction.

Combined with the light target nuclei, CRESST-II has potential to explore < 1 GeV dark matter particle

Franz Pröbst

Extends searches to sub-GeV range

Systematic studies still ongoing. Follow-up programme with 50–100 eV threshold starts in Apr 2016


Direct dark matter searches: XENON1002nd phase of XENON DM experiment at LNGS running since 2009, predecessor of XENON1T

uses 61 (100) kg target (active veto) liquid-gas xenon filled TPC. High-density, high atomic number, sensitivity to spin-dependent interactions through ~50% odd isotopes, low threshold due to high ionization and scintillation yield, low backgrounds, self-shielding target. LXe scintillation light measured by PMTs. Light from prompt scintillation (S1) and delayed ionization (S2) allows to discriminate ER from NR.

Constanze Hasterok

2012/2013 results:

Recent result (2015) addresses DAMA’s periodic signal: XENON100 does not find significant periodicity, DAMA phase & amplitude excluded at 4.8σ; DAMA-like DM models excluded to at least 3.6σ

Follow-up programme XENON1T commissioning almost completed, first results expected this year

XENON10

CDMS

ZEPLIN−III

WIMP Mass [GeV/c2]

SD

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P−

neut

ron

cros

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n [c

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101

102

103

104

10−40

10−39

10−38

10−37

10−36

10−35

10−34

XENON100 limit (2013)± 2σ expected sensitivity± 1σ expected sensitivity

XENON10

CDMS

PICASSO

COUPP

SIMPLE

KIMS

IceCube (bb)

IceCube W+ W

−

WIMP Mass [GeV/c2]

SD

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prot

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sec

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[cm

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proton

101

102

103

104

10−40

10−39

10−38

10−37

10−36

10−35

10−34

10−33 XENON100 limit (2013)

± 2σ expected sensitivity± 1σ expected sensitivity

]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000

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-4310

-4210

-4110

-4010

-3910

]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000

]2W

IMP

-Nuc

leon

Cro

ss S

ecti

on [

cm

-4510

-4410

-4310

-4210

-4110

-4010

-3910

]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000

]2W

IMP

-Nuc

leon

Cro

ss S

ecti

on [

cm

-4510

-4410

-4310

-4210

-4110

-4010

-3910

DAMA/I

DAMA/Na

CoGeNT

CDMS (2010/11)EDELWEISS (2011/12)

XENON10 (2011)

XENON100 (2011)

COUPP (2012)

SIMPLE (2012)

ZEPLIN-III (2012)

CRESST-II (2012)

XENON100 (2012)observed limit (90% CL)

Expected limit of this run:

expectedσ 2 ± expectedσ 1 ±


Direct dark matter searches: LUXLiquid-Xe experiment at Sanford, South Dakota, US, 1.5 km underground

is very similar as XENON100 based on a dual-phase Xe target. LUX has larger active target and lower threshold (3 keV vs. 6.6 keV), ie, sensitivity to lower WIMP masses.

Reanalysis of 2013 data (95 live days, 145 kg fiducial mass) with improved calibration, event reconstruction and background modelling improving the sensitivity especially at low WIMP masses

Spin-independent

Paolo Beltrame

101

102

103

10−1

100

101

102

103

104

105

8B

SuperCDMS 2014

CDMSlite 2015

PandaX 2015

DarkSide−50 2015

XENON100 2012

LUX 2014

This Result

mWIMP

( GeV/c2 )

WIM

P−nu

cleo

n cr

oss

sect

ion

( zb

)

10−45

10−44

10−43

10−42

10−41

10−40

WIM

P−nu

cleo

n cr

oss

sect

ion

( cm

2 )

S1 (phd)0 5 10 15 20 25 30 35 40 45 50

[S2(

phd)

]10

log

2

2.5

3

3.5

4

3 9

1.7

15

2.9

21

4.2

27

5.4

33 keVnr

6.6 7.8 9.0 10.2 keVee


)2WIMP Mass (GeV/c1 10 210 310 410 510

)2S

D W

IMP

-neu

tron

cro

ss-s

ectio

n (c

m

-4310

-4210

-4110

-4010

-3910

-3810

-3710

-3610

-3510

-3410

DAMA

ZEPLIN-IIICDMS

KIMS

MSDM g=0.25

MSDM g=1.45

PICASSO

XENON100

XENON10

LZ Projected

LUX 90% C.L.

)2WIMP Mass (GeV/c1 10 210 310 410 510

)2S

D W

IMP

-pro

ton

cros

s-se

ctio

n (c

m-4310

-4210

-4110

-4010

-3910

-3810

-3710

-3610

-3510

-3410

DAMA

ZEPLIN-IIICDMS

KIMSPICASSO

)bSuperK (b

)-W+SuperK (W)-τ+τ

SuperK (

PICO-2L PICO-60

XENON100

XENON10

LZ Projected

)b

IceCube (b

)-W+

IceCube (W

)-τ+

τIceCube (

LUX 90% C.L.

Direct dark matter searches: LUXLiquid-Xe experiment at Sanford, South Dakota, US, 1.5 km underground

is very similar as XENON100 based on a dual-phase Xe target. LUX has larger active target and lower threshold (3 keV vs. 6.6 keV), ie, sensitivity to lower WIMP masses.

LUX has also recently published spin-dependent limits using the same dataset

Spin-dependent elastic WIMP-proton scattering cross-sectionSpin-dependent elastic WIMP-neutron scattering cross-section

Paolo Beltrame

Follow-up programme LZ = LUX + ZEPLIN entering CD-2 review, start foreseen for 2025


Direct dark matter searches: OutlookHealthy experimental programme in preparation with orders of magnitude improved sensitivity

] 2WIMP mass [GeV/c6 10 20 30 100 200 1000 2000 10000

]2W

IMP-

nucl

eon

Cro

ss S

ectio

n [

cm

4910

4810

4710

4610

4510

4410

4310

4210

4110

4010

3910DAMA/Na

DAMA/ICDMS-Si (2013)

XENON10 (2013)

SuperCDMS (2014) PandaX (2014)DarkSide-50 (2015)

XENON100 (2012) LUX (2015)

y)*

XENON1T (2 t

yXENON1T Sensitivity in 2 tExpected limit (90% CL)

expected 2 expected 1

*LUX2015 model

] 2WIMP mass [GeV/c6 10 20 30 100 200 1000 2000 10000

]2W

IMP-

nucl

eon

Cro

ss S

ectio

n [

cm

4910

4810

4710

4610

4510

4410

4310

4210

4110

4010

3910DAMA/Na


XENON10 (2013)


XENON100 (2012) LUX (2015)

y)*

XENON1T (2 t

y)*

XENONnT (20 t



*LUX2015 model

] 2WIMP mass [GeV/c6 10 20 30 100 200 1000 2000 10000

]2W

IMP-

nucl

eon

Cro

ss S

ectio

n [

cm

4910

4810

4710

4610

4510

4410

4310

4210

4110

4010

3910DAMA/Na


XENON10 (2013)


XENON100 (2012) LUX (2015)

y)*

XENON1T (2 t

y)*

XENONnT (20 t

Billard et al., Neutrino Discovery limit (2013)



*LUX2015 model

Next generation experiments may reach irreducible coherent –N scattering background limit

Example extrapolation from XENONnT


Gravitational Waves

A new Popstarin science


Gravitational Waves

LIGO Hanford site (Washington, US) LIGO Livingston (Louisiana, US)

A new Popstarin science

VIRGO (Cascina, Italy) — not operating in Sep 2015

… reporting on Feb 11th, 2016 an earthshattering measurement


Gravitational Waves


Gravitational Waves: LIGO / VIRGOHuge signal of binary black hole merger in LIGO, first noticed by online burst detection system

measurement is an example of scientific perseverance

(a)

(b)

Spin-2 GW lengthens one arm while shortening other and vice versa in laser interferometer

ΔL = δLx − δLy = h(t) L

Optical signal measured proportional to strain h(t)

Enhancements to basic Michelson interferometer:

Test mass mirrors multiply effect of GW on light phase by ~300

Power recycling mirror on input amplifies laser light

Output signal recycling broadens bandwidth

Isolation of test masses from seismic noise, low thermal noise. Vibration isolation of all components and vacuum to reduce Raleigh scattering

System of calibration lasers and array of environmental sensors Two (better three!) detectors to localise GW and measure polarisation

Alessio Rocchi



Then, on Sep 14, 2015 at 09:51 UTC (11:51 am CEST) [total 16 days of simultaneous two-detector observational data]

H1 data shifted by 6.9 ms

Extremely loud event ( c = 23.6)

Maximum strain (10–21) times 4 km gives length deformation: 4×10–18 m ~ 0.5% size of proton

Measured spectrum well reproduced by GW calculation after fitting parameters

→ GW150914 (> 5.1σ over bkg)

Time series filtered with a 35–350 Hz bandpass filter to suppress large fluctuations outside the detectors’ most sensitive frequency band, and band-reject filters to remove the strong instrumental spectral lines seen on previous page

Times shown are relative to Sep 14, 2015 at 09:50:45 UTC

^

Alessio Rocchi



GW150914

Over 0.2 s, frequency and amplitude increase from 35 to 150 Hz (~8 cycles)

To reach 75 Hz orbital frequency, objects need to be very close ~350 km and massive (→ black holes)

Two black holes of initially 36 and 29 solar masses (M ) inspiral with ~half c

The black holes merge within tens of ms

Inspiral, merging and ringdown leave characteristic amplitude and frequency gravitational wave pattern

Total radiated GW energy 3.0 ± 0.5 M

It’s direct observation follows upon the demonstration of GW from energy loss in binary pulsar systems (1982)

Alessio Rocchi



Observation of GW150914 bundles several discoveries:

First direct detection of GWs

First observation of binary black hole merger

Relatively heavy stellar-mass black holes (> 25 M ) exist in nature

Observation of ”no-hair-conjecture”

Most relativistic binary event seen (v/c ~ 0.5)

Limit on graviton mass (< 1.2×10–22 eV)

Likely not a unique BBH event: inferred rate 2–400 Gpc–3 yr–1 at higher end of predictions

Adding VIRGO will improve localisation of GW; new interferometers upcoming in India & Japan

EM and high-E follow-up programme (no HEN coincidence seen by ANTARES and IceCube)

Alessio Rocchi



Observation of GW150914 bundles several discoveries:



Relatively heavy stellar-mass black holes (> 25 M ) exist in nature

Most relativistic binary event seen (v/c ~ 0.5)

Best limit on graviton mass (< 1.2×10–22 eV)

Likely not a unique BBH event: inferred rate 2–400 Gpc–3 yr–1 at higher end of rate predictions

Adding VIRGO will improve localisation of next observation; new interferometers upcoming in India & Japan

EM and high-E follow-up programme (no HEN coincidence seen by ANTARES and IceCube)

Observation of GW150914 bundles severaldiscoveries:



Relatively heavy stellar-mass black holes (> 25 MMM ) exist in nature

Most relativistic binary event seen (v/vv c ~ 0.5)

Best limit on graviton mass (< 1.2×10–22 eV)

Likely not a unique BBH event: inferred rate 2–400 Gpc–3 yr–1 at higher end of rate predictions

Adding VIRGO will improve localisation of nextobservation; new interferometers upcoming in India & Japan

EM and high-E follow-up programme (no HENcoincidence seen by ANTARES and IceCube)

Gravitational waves joined the club for multi-messenger astronomy together with photons, cosmic rays, neutrinos

PRL116, 061102 (2016): Huge impact paper: >100 citations within 1 monthcf: ATLAS/CMS July 2012 Higgs discovery papers have > 5600 citations by now

LIGO/Virgo published (so far) 12 follow-up papers about detector & analysis details and implications of GW150914

Alessio Rocchi


Every galaxy is expected to host supermassive black holes with > 1M sun masses in its centre, formed during galaxy creation process

NGC 4889, the brightest elliptical galaxy in the Coma cluster (94 Mpc ~ 300 Mly from earth), hosts a record BH of 21 billion times mass of Sun, event horizon diameter of ~130B km (Sun: 1.4M km)

From NASA/ESA Hubble Space Telescope, 11 Feb 2016https://www.spacetelescope.org/news/hei c1602


Flavour Physics

(Heavy) flavour physics

Study flavour mixing & CP violation in all its aspects

Look for new physics far beyond the current energy frontier in rare and forbidden processes

By these measurements we hope to get insight into the mystery of the observed flavour structure (which is related to Higgs sector)

The cavern in the North Area shortly before the NA62/2 run in autumn 2014


)2 cC

and

idat

es /

( 1

MeV

/0

50

100

150

200

250

300Claimed X(5568) state

Combinatorial

LHCb Preliminary

Pu

ll

-4-2024

]2c) [MeV/±πs0m(B

5520 5540 5560 5580 5600 5620 5640 5660 5680 5700

Hadron zoo: XYZ mesonsTopic of Moriond QCD, only this much…

announced new state in m(Bs(→J/ φ) π±) spectrum which may be a tetra-quark (bsud) [ 1602.07588, Feb 2016 ]

π π

Picture from Stephen Lars Olsen, La Thuile 2016

5.5 5.55 5.6 5.65 5.7 5.75 5.8 5.85 5.90

20

40

60

80

100

120

140

]2 ) [GeV/c S0 (Bm

2 )

/ 20

MeV

/c S0

N (

B

-1 D0 Run II, 10.4 fb

did not confirm the observation in 20 times larger Bs sample. Upper limit on ρ ~ 1%, but this may depend on beam/energy/ analysis. No public material yet, but more informa-tion expected this week.

mX ~ 5568 MeVΓX ~ 22 MeV

ρ(X→Bs /Bs) ~ 5–12%

Jeroen van Tilburg

Other experiments are also looking


The CKM matrix and moreLong-term effort to overconstrain CKM matrix continues. Huge contributions from LHCb

dmK

K

sm & dm

ubV

sin 2

(excl. at CL > 0.95) < 0sol. w/ cos 2

excluded at CL > 0.95

-1.0 -0.5 0.0 0.5 1.0 1.5 2.0-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5excluded area has CL > 0.95

EPS 15

CKMf i t t e r

Jeroen van Tilburg

LHCb reported:

|Vub / Vcb| from Λb → pμ at 5% precision (closer to exclusive B-factory result)

World’s best single Δmd measurement: 0.5050 ± 0.0021± 0.0010 ps–1

(B-factories: σave = 0.005 ps–1)

Precision on sin(2 ) approaches that of B-factories: 0.73 ± 0.04 ± 0.02

World’s best constraints on CP violation in B0

(s) mixing (asls, asl

d) in agreement with SM (D0 sees 3.6σ deviation)

Search for CPT violation (difference in mass or width) in B0

(s) system, measurement of sidereal phase dependence of CPT violating parameter

(tree) together with sin(2ß) (mix) or |Vub| (tree), fixes the unitarity triangle. All other measurements probe these two.


The CKM matrix and moreHuge LHCb effort on CKM angle γ

can be measured through interference of b → u with b → c tree transitions

Malcolm John

b

u

c

u

W− s

u

B− D0

K−b

u

u

u

W−

s

c

B−

K−

D0

Hadronic parameters are: rB and strong FSI phase δB

Theoretically clean measurement, but large statistics needed due to CKM suppression of amplitudes.

Hence use B±, B0, Bs, and many D decay modes requiring different techniques; also DK* and DsK used. Some modes show large CP asymmetries (example below)

ADS: B±→ Dh±, D→ π+K–

5100 5200 5300 5400 5500

)

2 cE

vent

s / (

10

MeV

/

50

100

KD]+K[B

LHCb

5100 5200 5300 5400 5500

0

0

+KD]K+[+B

LHCb

8σ

5100 5200 5300 5400 5500] 2c) [MeV/Dh(m

5100 5200 5300 5400 5500

]° [γ

1-C

L

0

0.2

0.4

0.6

0.8

1

0 50 100 150

68.3%

95.5%

LHCbPreliminary

Bs

decays

B0

decays

B+ decays

Com

bina

tion

γcombined = 71 deg+7– 8

CKM fit: 68 ± 2 deg(γ measurement not in fit)


Charm @ LHCb: CP violation and mixingExploiting huge recorded charm sample from Run-1

mixing frequency extremely low, challenging high-statistics measurement, CP violation small in SM

New mixing analysis using D0 → K– π+ π– π+. Sensitive to strong phase difference needed for γmeasurement via B+ → D0K+ (with D0 → K– π+ π– π+)

R(t) ≈ (rK3πD

)2 − rK3πD RK3π

D · y′K3π

t

τ+

x2 + y2

4

(t

τ

)2WS D0 → K+ π– π+ π–

––– (t) = –––––––––––––– (t) =RS D0 → K– π+ π– π+

sensitive to mixing, to ratio of CF to DCS amplitudes and their interference (strong phase δ)

τt /2 4 6 8 10 12

WS/

RS

3

3.5

4

4.5

5

5.5

63−10×

LHCb

DataUnconstrained fitNo-mixing fit

Using 11.4M RS, 43k WS

Confirms charm mixing

Taking x, y from WA, allows to measure RK3π

D · y′K3πrK3πD R

Alex Pearce

&

New results were shown for CP violation in charm:

ΔACP = ACP(D0/D0 → K+K–) – ACP(D0/D0 → π+π–)

D0 flavour inferred from soft pion charge in: D*+ → D0 π+

Earlier 0.6 fb–1 result exhibited 3.5σ discrepancy with SM, not confirmed with larger data sample.

New, full 3 fb–1 result:

ΔACP = −0.10 ± 0.08stat ± 0.03syst %

– –


Rare B decaysBs → μμ decay unambiguously observed by CMS & LHCb in Nov 2014 using Run-1 dataset

Relatively precise SM prediction, measurable branching fraction

Long search before it was finally observed

B0s

X+

W−X0

t

b

s

μ+

μ−

B0s

W+

W−Z0

t

b

s

μ+

μ−

Year1985 1990 1995 2000 2005 2010 2015

BR

UL(

95%

CL)

or

mea

sure

men

t

-1010

-910

-810

-710

-610

-510

-410

-μ+μ → 0sSM: B

-μ+μ → 0SM: BBelleL3CDFUA1CLEOARGUS

ATLASCMSLHCbD0BABAR

2011 2012 2013 2014

-910

-810

-710EPS2013

Johannes Albrecht, Sanjay Kumar Swain


Rare B decaysBs → μμ decay unambiguously observed by CMS & LHCb in Nov 2014 using Run-1 dataset

Relatively precise SM prediction, measurable branching fraction

B0s

X+

W−X0

t

b

s

μ+

μ−

B0s

W+

W−Z0

t

b

s

μ+

μ−

]2c [MeV/−μ+μm5000 5200 5400 5600 5800

)2 cS

/(S

+B

) w

eigh

ted

cand

. / (

40 M

eV/

0

10

20

30

40

50

60 DataSignal and background

−μ+μ →s0B

−μ+μ →0BCombinatorial bkg.Semileptonic bkg.Peaking bkg.

CMS and LHCb (LHC run I)

SM

0BS0 1 2 3 4 5 6 7 8 9

Lln

Δ2−

0

2

4

6

8

10SM

c

SMs0B

S0 0.5 1 1.5 2 2.5

Lln

Δ2−

0

10

20

30

40SM

b

B → μμ

Bs → μμ

B(Bs → μμ) = 2.8 × 10–9 (6.2σ) | SM: 3.7 ± 0.2 × 10–9

B(B → μμ) = 3.9 × 10–10 (3.2σ) | SM: 1.1 ± 0.1 × 10–10

+0.7–0.6

CMS & LHCb combined:

+1.6–1.4

Johannes Albrecht, Sanjay Kumar Swain


Rare B decaysPreliminary Run-1 Bs → μμ search presented at this conference by ATLAS

Features:

BDT to suppress hadrons faking muons (fight peaking backgrounds)

BDT to suppress continuum background

2D fit to cont. BDT bins & m (μμ) (unbinned)

Event yield normalised to B+ → J/ K+ (input: fs /fd)

Control channels: B+ → J/ K+ and Bs → J/ φ

3.1σ expected significance for Bs → μμ [SM]

BR(Bs → μμ) = 0.9 × 10–9

< 3.0 × 10–9 (95% CL)

BR(B → μμ) < 4.2 × 10–10 (95% CL)

+1.1–0.8

Compatibility with SM: 2.0σ

Sandro Palestini

di-muon mass [MeV]

4800 5000 5200 5400 5600 5800

Eve

nts

/ 40

MeV

0

5

10

15

20

25

30

35

40 2011-2012 dataTotal fitCombinatorial bkgSS-SV bkg

+ sB

PreliminaryATLAS

-1= 7 TeV, 4.9 fbs-1= 8 TeV, 20 fbs

0.346 < BDT < 0.446

di-muon mass [MeV]

4800 5000 5200 5400 5600 5800

Eve

nts

/ 40

MeV

0

2

4

6

8

10

12

14

16

18 2011-2012 dataTotal fitCombinatorial bkgSS-SV bkg

+ sB

PreliminaryATLAS

-1= 7 TeV, 4.9 fbs-1= 8 TeV, 20 fbs

0.446 < BDT < 1.000


Flavour anomaliesb → s μ+μ– continues to produce interesting results, more channels added

showed results with full angular analyses for K*μμ (8 independent CP-averaged observables). Best experimental precision on AFB, FL, …

Also angular and diff. BR analysis of Bs → φμμ, and diff. BR analysis of B+ → K+μμ

Johannes Albrecht

b sW

γ, Z0

t μ−

μ+

b s

μ+

μ−

di

H0

g

Use ratio to cancel FF dependence: Full Run-1 dataset and new analysis confirms discrepancy

]4c/2 [GeV2q0 5 10 15

5'P

-2

-1

0

1

2LHCb

SM from DHMV

Global fit with new physics parameterisation (C9NP, C10

NP) seems to reproduce observed discrepancy pattern

]4c/2 [GeV2q5 10 15

]4 c-2

GeV

-8 [

102 q

)/d

μμ

φ→ s0

BdB

( 0

1

2

3

4

5

6

7

8

9

SM pred.SM (wide)SM LQCDDataData (wide)

LHCb

Differential branching ratio of Bs → φμμ decay

P’5 measurements from ATLAS & CMS in work


Flavour anomaliesLess plagued by hard to estimate theoretical uncertainties are lepton universality tests

measure ratios of semileptonic B decays. Robust SM predictions

Johannes Albrecht, Pablo Goldenzweig

]4c/2 [GeV2q0 5 10 15 20

KR

0

0.5

1

1.5

2

SM

LHCbLHCb

LHCb BaBar Belle

R(D)0.2 0.3 0.4 0.5 0.6

R(D

*)

0.2

0.25

0.3

0.35

0.4

0.45

0.5BaBar, PRL109,101802(2012)Belle, arXiv:1507.03233LHCb, arXiv:1506.08614Average

= 1.02χΔ

SM prediction ) = 55%2χP(

HFAG

Prel. EPS2015

New measurement by Belle using semileptonic tagging of recoil B:

RD* = 0.302 ± 0.030stat ± 0.011syst [SM: 0.252 ± 0.003, 1.6σ]

Also studied kinematic distributions (additional NP sensitivity)

HFAG: p-value for SM: 3.9σ

Belle semilep.


Charged lepton flavour violation: SM-free signals!A very active field of BSM searches

1940 1960 1980 2000 2020

Year

90%

–CL

boun

d

10–14

10–12

10–10

10–8

10–6

10–4

10–2

100

μ eγ

μ 3e

μN eN

τ μγ

τ 3μ

Only null observation to date

Mar

cian

o et

al.,

Ann

u. R

ev.

Nuc

l. P

art.

Sci

.58,

315

(20

08),

up

dat

ed


Charged lepton flavour violationNew analysis of NA48/2 2003–2004 data sample to search for lepton number violation

looked for the decay: K+ → π– μ+ μ+ (negligible contribution from SM or neutrino oscillation expected)

Karim Massri

Main background from K+ → π– π+ π+ with 2 π+ → μ+ decays

Total of 2×1011 K± decays in fiducial detector volume

± π μ±μ± ×

M

o

No excess observed. Strong 90% CL limit:

BR(K+ → π– μ+ μ+ ) < 8.6 ×10–11

Also looked into di-muon invariant mass of opposite sign K+ → π+ μ+ μ– sample for resonances. None seen.

Outlook for NA62: expect to reach 10–12

LFV sensitivity (and 10–11 for π0 → eμ)


Rare kaon decays: NA62New result on 2007 dataset and /2 is ramping up

presented new measurement on 2007 dataset:

π0

γ

γ

e−

e+F (x)

− pe−)

x)

mπ0)2 ≡ xmin):

≈ 1 + a x + …F(x)

(in timelike region)π0, η, η′

x0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Eve

nts

/ 0.0

1

10

210

310

410

510Data

D0π ±π → ±K

ν±μ D0π → ±K

NA62Preliminary

~1.1 M fully reconstructed

Dalitz π0

TFF slope0π0.1− 0.05− 0 0.05 0.1

Geneva-Saclay (1978)

Saclay (1989)

SINDRUM I @ PSI (1992)

TRIUMF (1992)

NA62 (2016)

30k eventsFischer et al.

32k eventsFonvieille et al.

54k eventsMeijer Drees et al.

8k eventsFarzanpay et al.

1M events(preliminary)

aNA62 = (3.70 ± 0.53stat

± 0.36syst) × 10–2

Measurement of timelike transition form-factor (TFF) slope with π0 → e+e–γDalitz decays (1.2% BR) using ~5B triggered π0 from K±→ π±π0 (~20B K± in decay region)

TFF important to model muon g–2 LBLS contribution (other experimental information from spacelike measurements of e+e– → e+e–γ*γ* → e+e–π0 by CELLO, CLEO, BABAR)

Challenge for F(x) extraction: rad. corrections (included in MC)

F(x) fit using MC templates

Giuseppe Ruggiero


towards a measurement of K+ → π± (SM: (8.4 ± 1.0) × 10–11, BNL E949: (17 ± 11) × 10–11) Additional physics goals: standard kaon physics and new physics searches

Goal: 10% K+ → π± BR measurement

Requirements: 5 trillion K+ decays (~50 signal events) / year (possibly already in 2016)

similar order for background suppression (< 10 events / year, dominated by K+ → π±π0)

Rare kaon decays: NA62/2Eagerly awaited results on K+ → π± are on their way. 2014/15 data for commissioning

]4/c2 [GeVmiss2m

-0.04 -0.02 0 0.02 0.04 0.06 0.08 0.1 0.12

mis

s2

dmΓd

to

tΓ1

-710

-610

-510

-410

-310

-210

-110

1

)γ(μν+

μ→+K

eν0π+ e→+

K

μν0π+μ→+K

)γ(0π+π→+K

)1010× (νν+π→

+K

-π+π+π→+K0π0π+π→+

K

eν+e-π+

π→+K

Reg

ion

I

Region II

Most sensitive variable: m2miss = (pK+ – pπ+)2

PIDPhoton rejection

Giuseppe Ruggiero

K decay

2015 dataOTS + Kaon ID + Vertex cut

Region I

Reg

ion

II

Clo

se to

des

ign

per

form

ance


Electroweak precision physics

The LHC experiments —as do D0 & CDF since long, and continuing —are investing efforts into precision measurements of EW observables: mW, mtop, sin2θW

All are very challenging

[GeV]tm140 150 160 170 180 190

[G

eV]

WM

80.25

80.3

80.35

80.4

80.45

80.568% and 95% CL contours

measurementst and mW

fit w/o M measurements

H and M

t, m

Wfit w/o M

measurementst and mW

direct M

1 world comb. WM 0.015 GeV = 80.385 WM

1 world comb. tm = 173.34 GeVtm

= 0.76 GeV GeV theo 0.50 = 0.76

= 125.14 GeV

HM = 50 G

eV

HM = 300 G

eV

HM = 600 G

eV

HMG fitter SM

Jul ’14

MW = 80.3584± 0.0046mt ± 0.0030δtheomt ± 0.0026MZ± 0.0018Δαhad

± 0.0020αS ± 0.0001MH± 0.0040δtheoMW

GeV ,

= 80.358± 0.008tot GeV .

sin2θeff = 0.231488± 0.000024mt ± 0.000016δtheomt ± 0.000015MZ± 0.000035Δαhad

± 0.000010αS ± 0.000001MH± 0.000047

δtheo sin2θfeff

,

= 0.23149± 0.00007tot ,

SM Predictions [1407.3792, EW fit]

The LHC Run-1 is not over yet: high-quality, extremely well understood data sample for precision measurements

[ exp WA: σ = 15 MeV ]

[ exp WA: σ = 0.00016 ]

Global electroweak fit was masterpiece of LEP/SLD era. Discovery of Higgs over-constrains the fit and

dramatically improves predictability


[pb]tt

σ

50 100 150 200 250 300 350

ATLAS+CMS Preliminary = 7 TeV s summary, tt

σ

(*) Superseded by results shown below the line

WGtopLHC Mar 2016

NNLO+NNLL PRL 110 (2013) 252004, PDF4LHC = 172.5 GeVtopm

scale uncertainty

uncertaintySα ⊕ PDF ⊕scale

total stat

(lumi)±(syst) ±(stat) ± tt

σ

Effect of LHC beam energy uncertainty: 3.3 pb (not included in the figure)

ATLAS, l+jets -1=0.7 fbintL 7 pb± 9 ± 4 ±179

ATLAS, dilepton (*) -1=0.7 fbintL pb 7− 8+ 11−

14+ 6 ±173

ATLAS, all jets (*) -1=1.0 fbintL 6 pb± 78 ± 18 ±167

ATLAS combined -1=0.7-1.0 fbintL 7 pb± 7− 8+ 3 ±177

CMS, l+jets (*) -1=0.8-1.1 fbintL 7 pb± 12 ± 3 ±164

CMS, dilepton (*) -1=1.1 fbintL 8 pb± 16 ± 4 ±170

(*)μ+hadτCMS, -1=1.1 fbintL 9 pb± 26 ± 24 ±149

CMS, all jets (*) -1=1.1 fbintL 8 pb± 40 ± 20 ±136

CMS combined -1=0.8-1.1 fbintL 8 pb± 11 ± 2 ±166

LHC combined (Sep 2012) -1=0.7-1.1 fbintL 6 pb± 8 ± 2 ±173

νμX→ATLAS, l+jets, b -1=4.7 fbintL 3 pb± 17 ± 2 ±165

, b-tagμATLAS, dilepton e -1=4.6 fbintL 3.6 pb± 4.2 ± 3.1 ±182.9

missT-E

jets, NμATLAS, dilepton e -1=4.6 fbintL 3.3 pb± 9.5−

9.7+ 2.8 ±181.2

+jetshadτATLAS, -1=1.7 fbintL 46 pb± 18 ±194

ATLAS, all jets -1=4.7 fbintL 7 pb± 57− 60+ 12 ±168

+lhadτATLAS, -1=4.6 fbintL 3 pb± 23 ± 9 ±183

CMS, l+jets -1=5.0 fbintL 3.6 pb± 12.0 ± 6.0 ±161.7

μCMS, dilepton e -1=5.0 fbintL 3.8 pb± 4.0− 4.5+ 2.1 ±173.6

+lhadτCMS, -1=2.2 fbintL 3 pb± 22 ± 14 ±143

+jetshadτCMS, -1=3.9 fbintL 3 pb± 32 ± 12 ±152

CMS, all jets -1=3.5 fbintL 3 pb± 26 ± 10 ±139

(GeV)+lψJ/M0 50 100 150 200 250

Eve

nts

/ ( 1

0 G

eV )

0

20

40

60

80

100

3.04) GeV± = (173.53 tM

+ Jets channelμ/eμμ/ee/μe/

PreliminaryCMS (8 TeV)-119.7 fb

(GeV)tM170 180

)m

ax-lo

g(L/

L0

1

2

3

4

Traditional kinematic top mass measurement method approaches systematic limit of b-quark hadronisation

Ways to improve (lot of pioneering work by CMS):

Choose more robust observables (eg, wrt. b fragmentation)

Electroweak precision measurementsTop mass from LHC and Tevatron

Benjamin Stieger

LHC kinematic top mass measurements:

Select charmed mesons (rare but very clean signature)

Use dilepton kinematic endpoint (clean but large theoretical uncertainties)

Use cross-sections or differential variables (promising but difficult to achieve competitive precision

Currently best result (CMS): 1.7 GeV uncertainty

We heard a beautiful talk about alternative methods to measure the top mass


have extracted weak mixing angle from Z/γ* asymmetry measurements

Uncertainties at Tevatron dominated by statistical uncertainties, LHCb equally, ATLAS & CMS by PDF uncertainties.

Data-driven “PDF replica rejection” method applied by CDF

Complex measurements (in particular physics modelling) that are important to pursue, but precision of hadron colliders not yet competitive with LEP/SLD

Electroweak precision measurementssin2θW and Z asymmetries from hadron colliders

Arie Bodek, William James Barter

effWθ

2sin

0.224 0.226 0.228 0.23 0.232 0.234effWθ

2sin

0.224 0.226 0.228 0.23 0.232 0.234

0.0002±0.2315

0.0003±0.2322

0.0003±0.2310

0.0005±0.2315

0.0010±0.2315

0.0012±0.2308

0.0032±0.2287

0.0011±0.2314

0.0015±0.2329

0.0012±0.2307

LEP + SLD

(b)FBLEP A

LRSLD A

D0

CDF

ATLAS

CMS

LHCb

=7TeVsLHCb

=8TeVsLHCb

Phys. Rept. 427 (2006) 257

Phys. Rept. 427 (2006) 257

Phys. Rev. Lett. 84 (2000) 5945

Phys. Rev. Lett. 115 (2015) 041801

Phys. Rev. Lett. D89 (2014) 072005

arXiv:1503:03709

Phys. Rev. Lett. D84 (2011) 112002

+ Newest CDF result: 0.23221 ± 0.00046

Figure from LHCb 1509.07645


have presented progress towards the (challenging) mW measurement at the LHC

Measurement relies on excellent understanding of final state

Observables: pT, , pT, , mT as probes of mW

Challenges, high-precision:

Momentum/energy scale (incl. had. recoil) calibration: Z, J/ , Y

Signal efficiency and background modelling

Physics modelling:

o Production governed by PDF & initial state interactions (pert & non-pert): use W+, W–, Z, W+c data for calibration, and NNLO QCD calculations + soft gluon resummation

o EW corrections well enough known

o Probes very sensitive to W polarisation (and hence to PDF, including its strange density)

Electroweak precision measurementsW mass: towards a first measurement at the LHC via decay to lepton + neutrino

Mariarosaria D'Alfonso

0

0.25

0.5

0.75

1

80.2 80.3 80.4 80.5 80.6

Entries 0

80.2 80.6MW[GeV]

ALEPH 80.440±0.051

DELPHI 80.336±0.067

L3 80.270±0.055

OPAL 80.415±0.052

LEP2 80.376±0.033χ2/dof = 49 / 41

CDF 80.389±0.019

D0 80.383±0.023

Tevatron 80.387±0.016χ2/dof = 4.2 / 6

Overall average 80.385±0.015

Current experimental picture for mW

Project: Experiments are in a vigorous process of addressing the above issues. Many precision measurements (differential Z, W + X cross sections, polarisation analysis, calibration performance, …) produced on the way. Also theoretical developments mandatory. Long-term effort.


presented a new m(Z) measurement using a W-like Z → μμ analysis (replacing one μ by recomputed MET)

Electroweak precision measurementsW mass: towards a first measurement at the LHC via decay to lepton + neutrino

Mariarosaria D'Alfonso

Proof-of-principle analysis, but differences with full m(W) analysis remain: event selection, background treatment and of most of the theory uncertainties, …

7 TeV dataset used (lower pileup)

Scale and resolution calibration relies on J/ & Y

Track-based MET

W transverse recoil calibrated using Z+jets events

Results (depending on observable used):

Statistical errors: 35–46 MeV

Total systematics: 28–34 MeV

QED radiation: ~23 MeV (dominant)

Lepton calibration: 12–15 MeV

LEP


The LHC at 13 TeV

Huge milestone achieved in 2015 with record proton–proton collision energy of 13 TeV

After a rocky start, the LHC delivered Lint = 4.2 fb–1, Lpeak = 5.0×1033 cm–2 s–1

This luminosity already increase the new physics reach for many searches

Great year for experiments with many results available for the summer conferences, and a huge amount for the end-of-year jamboree, and much more at this conference

Expect 1×1034 cm–2 s–1 and ~30 fb–1 in 2016

Jörg Wenninger


l t0

500

1000

1500

2000

2500

3000

3500

4000

4500

Tota

l In

teg

rate

d L

um

inosit

y (

pb

¡1)

Preliminary Offline Luminosity

LHC Delivered: 4012.95 pb¡1

CMS Recorded: 3610.95 pb¡1

0

500

1000

1500

2000

2500

3000

3500

4000

4500

Day in 2015

27/05 28/06 30/07 31/08 02/10 04/11

]-1

Tot

al In

tegr

ated

Lum

inos

ity [f

b

0

1

2

3

4

5

6 = 13 TeVs ATLAS Online Luminosity

LHC Delivered

ATLAS Recorded

-1Total Delivered: 4.34 fb-1Total Recorded: 4.00 fb

Peak luminosity:

Lmax = 5.2 × 1033 cm–2 s–1

2015 LHC proton–proton luminositiesMost results reported at this conference use total 2015 datasets

LHCb after luminosity levelling: 0.32 (0.36) fb–1 recorded (delivered)

Luminosity monitors calibrated with beam-separation scans. Current precisions: 5.0% (ATLAS), 2.7% (CMS), 3.8% (LHCb)

Pileup profiles: ATLAS/CMS: <μ>50 ns = 20, <μ>25 ns = 13 (<μ>8TeV = 21), LHCb: <μ> ~ 1.7

Total in 2015 (recorded): B = 3.8 T: 2.9 fb–1

B ≠ 3.8 T: 0.8 fb–1

(due to problem with cryogenic supply)

3.3–3.6 fb–1 for physics 2.3–3.3 fb–1 for physics

Jörg Wenninger


SM and Top Physics

Celebrated last year at Moriond EW the 20th anniversary of the top discovery at the Tevatron

Dimuon mass distribution collected with various dimuon triggers by CMS

CDF plot


Inclusive W and Z productionVery rich physics: strong PDF dependence, probes for QCD, precision electroweak physics

studied single gauge boson production at 7, 8, 13 TeV, LHCb covers complementary phase space in x, Q2

William James Barter

-Wfidσ / +W

fidσ1.15 1.2 1.25 1.3 1.35

ATLAS Preliminary-113 TeV, 85 pb

total uncertaintystat. uncertainty

ABM12LHCCT10nnloNNPDF3.0MMHT14nnlo68CL

-Wfidσ / +W

fidσ = -/W+WR

Zfidσ / ±W

fidσ9 9.2 9.4 9.6 9.8 10 10.2 10.4 10.6 10.8

ATLAS Preliminary-113 TeV, 85 pb

total uncertaintystat. uncertainty

ABM12LHCCT10nnloNNPDF3.0MMHT14nnlo68CL

Zfidσ / ±W

fidσ = W/ZR

10.0 10.5 11.0

Preliminary CMS (13 TeV)-143 pb

Theory: FEWZ (NNLO)

Observation: NNPDF3.0

Observation

Uncertainty

(inner uncertainty: PDF only)

Ztotσ/W

totσ

NNPDF3.0-0.06+0.0710.55

CT14-0.09+0.0910.55

MMHT2014-0.09+0.0810.53

ABM12LHC-0.02+0.0410.56

HERAPDF15-0.09+0.1110.61

1.25 1.30 1.35 1.40

Preliminary CMS (13 TeV)-143 pb

Theory: FEWZ (NNLO)

Observation: NNPDF3.0

Observation

Uncertainty

(inner uncertainty: PDF only)

-Wtotσ/+W

totσ

NNPDF3.0-0.012+0.0111.354

CT14-0.014+0.0141.350

MMHT2014-0.008+0.0111.348

ABM12LHC-0.004+0.0031.371

HERAPDF15-0.013+0.0141.353

Note: fiducial cross-section ratios Note: fiducial cross-section ratios

Leptonic decays of Z & W are also standard candles to verify and calibrate e/μ performance

13 TeV W/Z cross section measurements (→ right plots)

pT(Z) @ 8 TeV from ATLAS shows resummation needed at low pT to describe data, NNLO below data at high pT

Charge asymmetry results by CMS and LHCb rather well predicted by theory

LHCb high-rapidity cross sections well predicted with NNLO and PDFs

8 TeV Z → μμ angular analysis by CMS, sensitive to Z polarisation and decay structure

Also: LHCb σZ (2.0 < η < 4.5) in agreement with SM (PDFs)


Diboson productionHighly important sector of LHC physics, intimately related to electroweak symmetry breaking

studied diboson production at 7, 8, 13 TeV. Detailed inclusive, fiducial and differential cross-section analyses at 8 TeV. First 13 TeV results. Theoretical predictions at NNLO needed to match data.

Tiesheng Dai

Each of these measurements in an experimental tour de force

[fb

/GeV

]Z T

pΔ/

fid.

σΔ 1−10

1

Data 2012Powheg

MC@NLOSherpa

ATLAS

-1 = 8 TeV, 20.3 fbs

ν →Z ±W ℓ′ ℓℓ

[fb]

fid.

σΔ

1

10

[GeV]ZT

p0 50 100 150 200 250

Rat

io to

Pow

heg

1

1.5

2

∞

ZZ @ 13 TeV measured by ATLAS & CMS, WZ by CMS: all agree with SM

WW @ 8 TeV cross-sections agree with SM NNLO + pT resummation

WZ @ 8 TeV by ATLAS shows deviations from SM (NLO only)

Zγ @ 8 TeV by ATLAS & CMS, matched by NNLO SM predictions

VBS: evidence in W+W+qq channel, new 8 TeV results on (W/Z)γqq (CMS), and WZqq (ATLAS), no observation yet

Tri-boson process Wγγ& Zγγ observed by CMS, evidence for Wγγ by ATLAS

Large set of anomalous coupling limits


Top-antitop production at 13 TeVIncrease of cross section by factor of 3.3 over 8 TeV

studied top production in many ways at 13 TeV → very prompt analyses turn around

Pedro Ferreira da Silva

Not

revi

ewed

,for

inte

rnal

circ

ulat

ion

only

[TeV]s2 4 6 8 10 12 14

cro

ss s

ectio

n [p

b]t

Incl

usiv

e t

10

210

310WGtopLHC

ATLAS+CMS Preliminary Mar 2016)-1Tevatron combined 1.96 TeV (L = 8.8 fb)-1 7 TeV (L = 4.6 fbμATLAS e

)-1 7 TeV (L = 5 fbμCMS e)-1 8 TeV (L = 20.3 fbμATLAS e

)-1 8 TeV (L = 19.7 fbμCMS e)-1 8 TeV (L = 5.3-20.3 fbμLHC combined e

)-1 13 TeV (L = 3.2 fbμATLAS e)-1 13 TeV (L = 43 pbμCMS e

)-1 13 TeV (L = 85 pbμμATLAS ee/)-1ATLAS l+jets 13 TeV (L = 85 pb

)-1CMS l+jets 13 TeV (L = 42 pb

WGtopLHC

NNLO+NNLL (pp)

)pNNLO+NNLL (pCzakon, Fiedler, Mitov, PRL 110 (2013) 252004

uncertainties according to PDF4LHCS

α ⊕ = 172.5 GeV, PDF topm

[TeV]s13

600

800

1000

Robust eμ final state gives most precise inclusive results at all CM energies

Differential cross-section measurements at 13 TeV show reasonable modelling, though some deviations at large jet multiplicity


Single top quark productionIncrease of cross section by factor of 2.5 (t-channel) over 8 TeV

have so far released t-channel measurement at 13 TeV

Pedro Ferreira da Silva

q

q′

W

b

t

]Ve [Ts

Incl

usiv

e cr

oss-

sect

ion

[pb]

1

10

210

7 8 13

WGtopLHCATLAS+CMS PreliminarySingle top-quark productionMarch 2016

t-channel

Wt

s-channel

ATLAS t-channel

ATLAS-CONF-2015-079112006, ATLAS-CONF-2014-007, (2014) PRD90

CMS t-channel

CMS-PAS-TOP-15-004090, (2014) 035, JHEP06 (2012) JHEP12

ATLAS Wt064 (2016) 142, JHEP01 (2012) PLB716

CMS Wt231802 (2014) 022003, PRL112 (2013) PRL110

LHC combination, WtATLAS-CONF-2014-052, CMS-PAS-TOP-14-009

ATLAS s-channel

arXiv:1511.05980L., ATLAS-CONF-2011-118 95% C.

CMS s-channelL. arXiv:1603.02555 95% C.

58 (2014) PLB736NNLO , MSTW2008nnloVeG = 172.5topm

scale uncertainty

091503, (2011) PRD83NNLL + NLO054028 (2010) 054018, PRD81 (2010) PRD82

, MSTW2008nnloVeG = 172.5topm contribution removedtWt: t

uncertaintysα ⊕ PDF ⊕scale

74 (2015) 10, CPC191 (2010) NPPS205NLO ,top= m

Fμ=

Rμ, VeG = 172.5topm

CT10nlo, MSTW2008nlo, NNPDF2.3nlo (PDF4LHC)VeG 60 = removalt veto for tb

TWt: p

VeG 65 =F

μ and

scale uncertainty

uncertaintysα ⊕ PDF ⊕scale

VeG = 172.5top

All exp. results are w.r.t. m

stat syst

“t-channel”

“Wt-channel”

“s-channel”(not easier at 13 TeV)

Tevatron: 6.3σ, ATLAS Run-1: 3.2σ


Top-antitop production and a vector boson at 13 TeVFirst results on important ttV process, in it’s own right, and as background to ttH and searches

showed new 13 TeV results

Emmanuel Monnier

t

t

g

g Z

q′

q

W

qt

t

Different production processes and thus 13/8 TeV cross-section ratios for ttZ & ttW: 3.6 & 2.4

Analyses combine several multilepton final states, difficult mis-ID background

At 8 TeV, both processes observed, and found to agree with SM prediction (ttW ~1σ up in both ATLAS & CMS)

2j(=0b) 1b)≥2j( 3j(=0b) 3j(=1b) 2b)≥3j( 4j(=0b) 4j(=1b) 2b)≥4j(

Eve

nts

10

20

30

40

50

60

70

80

90

Ztt

WZ

Xtt

rare

data-driven

Data

(13 TeV)-12.7 fbCMSPreliminary

ATLAS: ttW: 1.38 ± 0.70 ± 0.33 pbttZ: 0.92 ± 0.30 ± 0.11 pb

CMS:ttZ: 1.07 pb

SM (NLO): ttW: 0.57 ± 0.06 pbttZ: 0.76 ± 0.08 pb

+0.35–0.31

+0.17–0.14

3L-WZ-CR4L-ZZ-CR

3L-noZ-2b-SSμ2

Dat

a / P

red.

0

0.5

1

1.5

2

Eve

nts

1

10

210

ATLAS Preliminary-1 = 13 TeV, 3.2 fbs

Post-Fit

Data Ztt

Wtt WZZZ tZ

tWZ Htt

Other Fake leptons

Uncertainty

Preliminary ttW/Z results from ATLAS, ttZ from CMS:


Top property measurementsThis is a huge field of research, studying polarisation, asymmetries, P/CP violation, FCNC

Emmanuel Monnier, Christian Schwanenberger

Tevatron AFB(tt) and NNLO SM prediction have converged towards each other

Charge asymmetries at LHC in agreement with SM

D0 has beautiful new measurement of P and CP-odd observables (CP-odd one found compatible with zero)

Asymmetry (%)20− 0 20 40

0.5−

6.5

D0 note 6445-CONF (2014)

)-1D0 Dileptons (9.7 fb 8.6±18.0

PRD 90, 072011 (2014)

)-1D0 Lepton+jets (9.7 fb 3.0±10.6

CDF Public Note 11161

)-1CDF Combination (9.4 fb 4.5±16.0

CDF Public Note 11161

)-1CDF Dilepton (9.1 fb 13± 12

PRD 87, 092002 (2013)

)-1CDF Lepton+jets (9.4 fb 4.7±16.4

NLO SM, W. Bernreuther and Z.-G. Si, PRD 86, 034026 (2012)

NNLO SM, M. Czakon, P. Fiedler and A. Mitov, arXiv:1411.3007

ttFBTevatron A

En

trie

s

050

100150200250300350400450

-1DØ, 9.7 fbDataNo Spin CorrWith Spin CorrBackground

Discriminant R0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1D

ata

- M

C

-500

50

Eve

nts/

0.1

0

2000

4000

6000

8000

10000

12000

14000

16000ATLAS

-1 = 8 TeV, 20.3 fbs

Data

tSM t

(A=0)tt

Background

, 180 GeV1t~1t

~

Fit

π [rad] / φΔ0 0.2 0.4 0.6 0.8 1

8

Top-antitop spin correlations established at LHC, used by ATLAS to look for “stealth stop”. First 4.2σ evidence for spin correlations by D0.

FCNC processes t → qg, Zq, Hqprobed by ATLAS & CMS, no signal


Higgs boson Physics

Display of H → eeμμ candidate from 13 TeV pp collisions. The electrons have a transverse momentum of 111 and 16 GeV, the muons 18 and 17 GeV, and the jets 118 and 54 GeV. The invariant mass of the four lepton system is 129 GeV, the di-electron invariant mass is 91 GeV, the di-muon invariant mass is 29 GeV, the pseudorapidity difference between the two jets is 6.4 while the di-jet invariant mass is 2 TeV. This event is consistent with VBF production of a Higgs boson decaying to four leptons.


In 2015 ATLAS & CMS achieved full Run-1 Higgs combinationAs by product: combined observation of H → ττ decay and VBF production mode

Parameter value0 0.5 1 1.5 2 2.5 3 3.5 4

μ

ttHμ

ZHμ

WHμ

VBFμ

ggFμ

Run 1LHC PreliminaryCMS and ATLAS ATLAS

CMSATLAS+CMS

σ 1±σ 2±

Parameter value0 0.5 1 1.5 2 2.5 3 3.5 4

bbμ

ττμ

WWμ

ZZμ

γγμ

Run 1LHC PreliminaryCMS and ATLAS ATLAS

CMS

ATLAS+CMS

σ 1±

Differential cross-section measurements

Limit on invisible Higgs branching ratio of < 25%

Constraints on anomalous off-shell coupling, spin/CP, LFV, forbidden decays (FCNC) and other scalar particles (BSM Higgs)

Higgs decay processes

combinations of Higgs mass and coupling measurements

Also:

Higgs production processes

13/8 TeV cross section ratios of 2~2.4 for VH, ggH, VBF, but 3.9 for ttH

→ K13/8 ~ 0.8 for ttH3.3/fb

Lidia Dell'Asta

mH = 125.09 ± 0.24 GeV


One word on lepton flavour violation in Higgs decaysBoth experiments have finalised their Run-1 LFV analyses

While H → μe is severely constrained from flavour physics, H → τμ, τe are not (~10% limits)

CMS released early 2015 a H → τμ search finding a slight (2.4σ) excess

ATLAS has completed full analysis (including H → τe) for this conference

Lidia Dell'Asta, Joachim Kopp

Meant to be examples of flavour violation?

S/(

S+

B)

Wei

ghte

d E

vent

s / 2

0 G

eV

0

10

20

30

40

50

60

Data

Bkgd. uncertainty

SM H

ττ→Z

Other

t, t, tt

μ, e, τMisID'd

LFV Higgs, (B=0.84%)

Data

Bkgd. uncertainty

SM H

ττ→Z

Other

t, t, tt

μ, e, τMisID'd

LFV Higgs, (B=0.84%)

(8 TeV)-119.7 fb

CMS

[GeV]col

)τμM(100 200 300

Bkg

d (f

it)D

ata-

Bkg

d (f

it )

-0.1

0

0.1

H → τμ:

ATLAS: BR = 0.53 ± 0.51% < 1.43% (95% CL)

CMS:BR = 0.84 % < 1.51% (95% CL)

H → τe:

ATLAS: BR = –0.3 ± 0.6% < 1.04%(95% CL)

+0.39–0.37


Current 13 TeV data sample still marginal for H125But important to look for the signal in an agnostic way at new CM energy

looked for Higgs decays to bosonic and fermionic channels

Seth Zenz

[GeV]4lm

80 90 100 110 120 130 140 150 160 170

Eve

nts/

2.5

GeV

0

2

4

6

8

10

12

14

16Data

= 125 GeV)H

Higgs (mZZ*

tZ+jets, t+V, VVV tt

Uncertainty

4l ZZ* H -113 TeV, 3.2 fb

ATLAS Preliminary

μ = σdata / σSM = 0.82

H →→ ZZ* → 4

+0.57– 0.43σtot,data = 12 pb

σtot,SM = 51 ± 5 pb

+25–16

Expected significance (SM): 2.8σ





Seth Zenz

μ = 0.69

H → γγ

+0.47– 0.42σtot,data = 40 ± 26 ± 2lumi pb

σtot,SM = 51 ± 5 pb

+16 –10






Seth Zenz

Extracted cross sections vs CM energy

[TeV] s7 8 9 10 11 12 13

[pb]

H

→ppσ

10−

0

10

20

30

40

50

60

70

80

90ATLAS Preliminary = 125.09 GeVHm H→ppσ

QCD scale uncertainty

)sα PDF+⊕(scale Tot. uncert. γγ→H l4→*ZZ→H

comb. data syst. unc.

-1 = 7 TeV, 4.5 fbs-1 = 8 TeV, 20.3 fbs

-1 = 13 TeV, 3.2 fbs

H → 4 , fiducial cross sectionCombined H → 4 , γγ


First search for ttH production at 13 TeV by CMSMost interesting of the SM channels at current luminosity

showed preliminary results for ttH in all major Higgs decay channels: H → γγ, multi-leptons, bb

Highly complex analyses, huge effort to get these done so quickly after data taking

Johannes Hauk g

g

t

H

t

H →→ γγ,tt → 0 & 1 leptons

μ = 3.8 +4.5– 3.6

ttH → multi-leptons2 same charge / 3 leptons

μ = 0.6 +1.4– 1.1

e±μ±

H → bbtt → 1 & 2 leptons

μ = –2.0 ±1.8 < 2.6 (95% CL)

= 125 GeVH at mSM

σ/σ = μBest fit

10− 5− 0 5

Combined

Dilepton

Lepton+Jets

CMS Preliminary (13 TeV)-12.7 fb


Searches — a fresh start*

*A few anomalies from Run-1 are to be followed up in Run-2

LHC-13


[GeV]Tm

Eve

nts

/ 10

GeV

110

1

10

210

310

410

510Diboson & single-toptt

Z+jets MisID j

MisID e/ 5) 200 GeV ( +H

W+jets 10) 1000 GeV ( +H

Data


[GeV]Tm210 310

Dat

a / S

M

00.5

11.5

2Uncertainty

Eve

nts

/ G

eV

3−10

2−10

1−10

1

10

210 Dataττ →H/A

= 25β = 500 GeV, tanAmMulitjet

ττ→Zντ→W

, single topttOthersUncertaintyPre-fit background

ATLAS Preliminary -1 = 13 TeV, 3.2 fbs

hadτhadτ →H/A

[GeV]totTm

200 300 400 500 600 700 800 900 1000Dat

a/P

red

012

BSM Higgs boson searchesSingle BEH doublet and form of potential simple but Nature may be more complex

(only results recalled here, more shown by Allison) mainly heavy BSM searches interesting

H+ → τ : sensitivity better than Run-1 at mass > 250 GeV

H / A → ττ: similarly, improved sensitivity at mass > 700 GeV

A → Z(→ , ) h125(→ bb): improved sensitivity > 800 GeV

H → ZZ(→ qq, qq, 4 ) / WW (→ qq): searches addressed 1–3 TeV mass range with boosted bosons

X → hh → bbγγ: small excess in Run-1 at mX~300 GeV, not yet excluded at 13 TeV

X → hh → bbττ resonant (and non-resonant) search

H+ → τ H / A → ττ

A → Zh

Allison McCarn

None of these many searches showed anomaly so far [GeV]kinfit

Hm300 400 500 600 700 800 900 1000

[1/G

eV]

kinf

itH

dN/d

m

4−10

3−10

2−10

1−10

1

10

210 CMSpreliminary

(13 TeV)-12.7 fb

Datatt

QCDDrell-YanOther bkg.bkg. uncertainty

= 800 GeVHm = 450 GeVHm = 300 GeVHm

hh) = 10 pb→ BR (H× H) →(ppσ

hτhτbb

channel

X → hh → bbττE

vent

s / 1

00 G

eV

1−10

1

10

210

310

410

510Data

=113 fb)σ Zh (→A=600 GeVAm

DibosonVhtt

Single topW+(bb,bc,cc,bl)W+clZ+(bl,cl)Z+(bb,bc,cc)Z+lUncertaintyPre-fit background

ATLAS Preliminary -1Ldt = 3.2 fb∫ = 13 TeV s

2 jets, 2 tags≥0 lep.,

< 500 GeVVT

p≤150 GeV

< 140 GeVbb

m≤110 GeV

(Vh) [GeV]Tm200 300 400 500 600 700 800 900 1000D

ata/

Pre

d.

0.5

1

1.5


Searches in high-pT multijet final states at 13 TeVProcesses with large cross-sections, sensitivity to highest new physics scales

Clemens Lange

Dijet resonance and angular distribution

High-pT multijets produced, eg, by strong gravity

High-pT lepton + jets (strong gravity)

Second generation scalar lepto-quark pair production (μq-μq final state, excl. < 1.2 TeV)

None of these searches showed an anomaly so far

Eve

nts

1

10

210

310

410

510

|y*| < 0.6Fit Range: 1.1 - 7.1 TeV

-value = 0.67pQBH (BM)

3× σ*, q

data

- fi

tS

igni

fican

ce

2−

0

2

[TeV]jjm2 3 4 5 6 7

MC

Dat

a-M

C

1−

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1JES Uncertainty

ATLAS-1=13 TeV, 3.6 fbs

DataBackground fitBumpHunter interval

= 4.0 TeV*q

*, mq = 6.5 TeV

thQBH (BM), m

1

10

|y*| <Fit Ra

-valupQBH

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data

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igni

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ce

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a-M

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0

1JES Uncertainty

[GeV]TS3000 4000 5000 6000 7000

Eve

nts

/ 0.1

TeV

-410

-310

-210

-110

1

10

210

310

410

510 CMS Preliminary

(13 TeV)-12.2 fb

8≥Data with multiplicity

Bkg prediction from data

= 5 TeV, n=6BH

= 4 TeV, MDM

= 6 TeV, n=6BH

= 4 TeV, MDM

= 7 TeV, n=6BH

= 4 TeV, MDM

= 8 TeV, n=6BH

= 4 TeV, MDM

[GeV]TS2500 3000 3500 4000 4500 5000 5500 6000 6500 7000

(Dat

a -

Fit)

/Fit

-2-1.5

-1-0.5

00.5

11.5

2


Searches in high-pT multijet final states at 13 TeVProcesses with large cross-sections, sensitivity to highest new physics scales

Pieter Everaerts

None of these searches showed an anomaly so far

Eve

nts

1

10

210

310

[TeV]jjm

Sig

nific

ance

2−1−012

1 2 3 4

ATLAS Preliminary -1=13 TeV, 3.2 fbsData

Background fitBumpHunter intervalSSM Z', 1.25 TeVLeptophobic Z', 1.5 TeV

2 b-tag

50× σSSM Z',

50× σLeptophobic Z',

p-value = 0.71

Eve

nts

20

40

60

80 Datatt

Other SM=1 pb)σZ' 3 TeV (

+jets, 1 t tagμe/ (13 TeV)-12.6 fb

PreliminaryCMS

[GeV]tt

M0 1000 2000 3000 4000

Dat

a/B

kg

0.51

1.5

Top-tagged data sample


Searches in leptonic final states (I)Canonical searches for new physics in high-mass Drell-Yan production (Z’, W’)

have analysed their full 2015 dataset and presented results for + – and final states

Eve

nts

210

110

1

10

210

310

410

510

610 Data*Z/

Top QuarksDibosonMulti-Jet & W+Jets

(3 TeV)Z’ = 20 TeV

-LL

PreliminaryATLAS-1 = 13 TeV, 3.2 fbs

Dilepton Search Selection

Dielectron Invariant Mass [GeV]90100 200 300 400 1000 2000 3000

Dat

a / B

kg

0.60.8

11.21.4

100

Good high-mass Drell-Yan modelling crucial → SM diff. cross-section measurements paired with searches

High-pT muon reconstruction challenges detector alignment

No anomaly found. SSM Z’ / W’ benchmark limits set at 3.4 / 4.4 TeV (2.9 / 3.3 TeV at 8 TeV)

ATLAS also looked into high-mass eμ (LFV) production. Main background top-antitop. No anomaly seen

m(ee) [GeV]70 100 200 300 1000 2000

Eve

nts

/ GeV

6−10

5−10

4−10

3−10

2−10

1−10

1

10

210

310

410

510Data

-e+e→/Zγ

ττ, tW, WW, WZ, ZZ, tt

Jets = 2 TeV)

Z'Narrow Z' (M

(13 TeV)-12.6 fb

CMSPreliminary

Ent

ries

110

1

10

210

310

410

510

610 -1 = 13 TeV, 3.3 fbs

DataWTop

*Z/DibosonMultijet

W’ (2 TeV)

W’ (3 TeV)

W’ (4 TeV)

PreliminaryATLAS

selection W’

Transverse mass [GeV]200 300 1000 2000

Dat

a / B

kg

0.60.8

11.21.4

Eve

nts

1−10

1

10

210

310

410

510

610 Data

νμ →W

tt

*γZ/

Diboson

SSM W' 2.4 TeV

SSM W' 3.6 TeV

CMSPreliminary

miss

T+Eμ

(13 TeV)-12.2 fb

(GeV)TM210×2 210×3 310 310×2 310×3

Dat

a/M

C

0

0.5

1

1.5

2

Systematic uncertainty band

James Catmore


M = 2.9 TeV !!!Display of rare colossal e+e– candidate event with 2.9 TeV invariant massEach electron candidate has 1.3 TeV ET

Back-to-back in φHighest-mass Run-1 events: 1.8 TeV (ee), 1.9 TeV (μμ)


Searches for diboson resonances (hh, Vh, VV)

High pT of bosons boosts hadronic decay products giving merged jets

as in the other searches: 10 Run-2 analyses presented. Hadronic decay modes use jet substructure analysis to reconstruct bosons. Important strong interaction backgrounds

Max Bellomo, Maurizio Pierini

Eve

nts/

100

GeV

-110

1

10

210

310ATLAS Preliminary

-1 = 13 TeV, 3.2 fbs

WZ selection

Data 2015

Fit bkg estimation

Fit exp. stats error

[GeV]JJm1000 1200 1400 1600 1800 2000 2200 2400

Pul

l

-202

Some excess of events around 2 TeV (globally 2.5σ for ATLAS) seen in WZ mode at 8 TeV in fully hadronic channel, not seen in the other decay channels

So far no excess in 13 TeV data around 2 TeV, also other diboson searches do not show anomaly

Eve

nts

/ 94.

7 G

eV

-110

1

10

210

310

410CMS data

2 par. background fit

= 0.029 pb)σWZ (→W'(2 TeV)

WZ, high-purity

> 200 GeVT

| < 2.4, pη|

| < 1.3jjηΔ > 1 TeV, |jjM

(13 TeV)-12.6 fb

CMSPreliminary

Dijet invariant mass [GeV]1000 1500 2000 2500 3000 3500

σD

ata-

Fit

-3-2-10123


Supersymmetry (I)With jets & MET

have updated their most sensitive SUSY searches using (b-)jets and MET

g

g

t

t

p

p

t

χ01

t

t

χ01

t

q

qp

p

χ01

q

χ01

q

g

gp

p

χ01

q

q

χ01

q

q

Benefit from improved background modelling (better generators & theory, better tuning), but can still find large scale factors from control region normalisation of SM processes in extreme corners of phase spacePersonal remark: need to make sure our analyses are optimised for discovery (not limits)

Eve

nts

/ 200

GeV

1

10

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410


-1 = 13 TeV, 3.3 fbsGtt 1-lepton pre-selection

Data 2015Total backgroundttSingle top + W/Z/htt

Z+jetsW+jetsDiboson

100)× σ = 1600, 200 (0

1χ∼

, mg~

Gtt: m

100)× σ = 1400, 800 (0

1χ∼

, mg~

Gtt: m

[GeV]incleffm

500 1000 1500 2000 2500 3000

Dat

a / S

M

0

1

2

[GeV]g~m1000 1200 1400 1600 1800 2000

[GeV

]10χ∼

m

0

200

400

600

800

1000

1200

1400

1600-1ATLAS 8 TeV, 20.1 fb

)expσ1 ±Expected limit (

)theorySUSYσ1 ±Observed limit (

t

+ 2m0

1χ∼ < mg~m

)g~) >> m(q~, m(0

1χ∼+t t→ g~ production, g~g~

All limits at 95% CL

PreliminaryATLAS-1=13 TeV, 3.3 fbs

-1ATLAS 8 TeV, 20.1 fb


)theorySUSYσ1 ±Observed limit (

600

10000

200

4000000000000000000000000000000000000000000000

No significant anomaly seen in 7 different jets + MET analyses presented

Chris Young


Supersymmetry (II)With leptons, jets & MET

target production of W/Z + jets + MET, as well as top through gluino decay (via stop)

g

g

t

t

p

p

t

χ01

t

t

χ01

t

Lower backgrounds than in jets + MET studies, but also lower signal

Henning Kirschenmann

9 searches presented, including two looking for same-charge lepton pairs and 3 leptons. No anomalies (apart from Z+MET)

g

g

χ02

χ±1

p

p

q q

χ01

Z/h

qq

χ01

W

Small excess (2.2σ) observed, 3σ excess was seen by ATLAS in that channel at 8 TeV

Excess was not confirmed by CMS/8 TeV, neither at 13 TeV

A small CMS/8 TeV excess (2.6σ) off-Z was not confirmed

[GeV]llm50 100 150 200 250 300 350 400

Eve

nts

/ 20

GeV

0

5

10

15

20

25

30

35 Data 2015

Standard Model (SM)

+jets)* (from Z/

Flavour symmetric

Rare top

WZ/ZZ

-1 = 13 TeV, 3.2 fbs

ee+

ATLAS Preliminary

[GeV]g~m

600 800 1000 1200 1400 1600

[GeV

]0 1χ∼

m

0

200

400

600

800

1000

1200

-310

-210

-110

1

(13 TeV)-12.3 fbCMS Preliminary

NLO+NLL exclusion1

0χ∼ ±' Wq q → g~, g~ g~ →pp

theoryσ 1 ±Observed

experimentσ 1 ±Expected

)0

1χ∼

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1χ∼m

95%

C.L

. upp

er li

mit

on c

ross

sec

tion

[pb]

SUS-15-006 Δɸ (0b)

Opposite sign dilepton search (here on-Z)


Third generation quark partnersSearches for direct production

may be the lightest sfermions. They have low cross-sections, so run-2 luminosity just enough to increase sensitivity

Vector-like quarks* (VLQ) singly or pair produced decay to bW, tZ or tH. Also exotic X5/3 → tW possible

Signatures are b-jets, jets, possibly leptons and MET

Pieter Everaerts

t

t

tW

tW

p

p

χ01

b �

ν

χ01

b

q

q

b

bp

p

χ01

b

χ01

b

*Hypothetical fermions that transform as triplets under colour and who have left- and right-handed components with same colour and EW quantum numbers

[GeV]1b

~m100 200 300 400 500 600 700 800 900 1000 1100

[GeV

]0 1χ∼

m

0

100

200

300

400

500

600

700

800

Best SR

forb

idde

n

01χ∼

b

→ 1b~

=8 TeVs, -1 + 2 b-jets, 20.1 fbTmissATLAS E

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0

1χ∼ b → 1b

~Bottom squark pair production,

-1=13 TeV, 3.2 fbs

ATLAS Preliminary)

theorySUSYσ1 ±Observed limit (



Total of 10 Run-2 analyses

No anomaly seen

Sensitivity improved over Run-1

Similar for VLQ searches


Mass [GeV]

0 500 1000 1500 2000 2500 3000

Ent

ries

/ 50

GeV

3−10

2−10

1−10

1

10

data

background) = 1200 GeVg~m() = 1600 GeVg~m(


stable selection

Searches in unconventional final statesATLAS & CMS also started to look for long-lived massive particle at 13 TeV

(due to: large virtuality, low coupling, mass degeneracy, eg, scale-suppressed colour triplet sclar from unnaturalness by Tony Gherghetta).

Multitude of signatures, some requiring dedicated triggers, most requiring dedicated analysis strategies.

Revital Kopeliansky

Mass from dE/dx measured in Pixel only (sensitivity to metastable particles)

Mass (GeV)0 1000 2000

Tra

cks

/ bin

2−10

1−10

1

10

210

Observed

Data-based SM prediction

Stau (M = 494 GeV)

(13 TeV)-12.4 fb

CMSPreliminary

Tracker + TOF

ATLAS and CMS have so far looked into heavy long-lived SUSY particles at 13 TeV

Analysis uses tracker dE/dx and TOF from muon system

[ns]τ

2−10 1−10 1 10 210 310 410

[GeV

]g~

Low

er li

mit

on m

600

800

1000

1200

1400

1600

1800

2000

2200

2400 ExpectedObserved

Phys. Rev. D92, 072004Displaced vertices Phys. Rev. D88, 112003Stopped gluino JHEP 01 (2015) 068Stable charged

ATLAS-CONF-2015-062 missTJets+E

To appearPixel dE/dx

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=8 TeVs, -118.4-20.3 fb

=13 TeVs, -13.2 fb

PreliminaryATLAS

Status: March 2016 = 100 GeV1

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1

0χ∼ g/qq → R-hadron g~

}}

=1)γβ=0, η(r for Beampipe Inner Detector Calo MS

Pro

mpt

Sta

ble

[m]τc

3−10 2−10 1−10 1 10 210 310 410


Searches for dark matter production at the LHCCanonical signature is ‘X+MET’ with large variety of ‘X’

Requires boost for triggering. Depending on coupling it can be made by different objects.

Matteo Cremonesi

DM

DM

SM

SM

DirectDetection

(DM collision nuclear recoils)

Indirect detection

Production at colliders

Energetic gluon/photon radiation in the initial sate

Eve

nts

/ 50

GeV

210

110

1

10

210

310

410

510

610


-1 = 13 TeV, 3.2 fbsSignal Region

>250 GeV miss

T>250 GeV, E

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Standard Model) + jets Z(

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ADD, n=3, M

[GeV]T

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Dat

a / S

M

0.5

1

1.5

Eve

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1

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10

2030

100

200300

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(13 TeV)-12.17 fb

CMSPreliminary 2 b-tag category

=1 GeVχ

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scalar mediator

DM + heavy flavour

(GeV)TE

200 300 400 500 600 700 800 900 1000Dat

a / B

kg

00.5

11.5

2 0.065±Data/Bkg = 1.030 /ndf = 1.03, K-S = 1.0002χ

pre-fit post-fit

Experimentally challenging to control Z/W+jetsbackground. Theory input needed.

Several 13 TeV results already available:

jets + MET

γ + MET

V + MET

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No anomaly seen so far


The return of the limits …

[GeV]

g~m

1000

1200

1400

1600

1800

2000

[GeV

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200

400

600

800

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Light quanta

Used since forever as detection probe

Recent example: H → yyFirst medical X-ray by Wilhelm Röntgen of his wife Anna Bertha

Ludwig's hand, Nov 1895[First Nobel price of physics, 1901]


Diphoton resonance searches: ATLASUpdated preliminary results presented this week

showed dedicated searches for a spin-0 and a spin-2 diphoton resonance.

Main difference is acceptance: spin-0: ET(γ1) > 0.4 mγγ, ET(γ2) > 0.3 mγγ, spin-2: ET(γ1/2) > 55 GeV

Photons are tightly identified and isolated. Typical purity ~94%

Background modelling empirical in spin-0, and (mainly) theoretical in spin-2 case (for high-mass search)

Marco Delmastro

Eve

nts

/ 20

GeV

1−10

1

10

210

310


Spin-0 Selection-1 = 13 TeV, 3.2 fbs

Data

Background-only fit

[GeV]γγm200 400 600 800 1000 1200 1400 1600

Dat

a -

fitte

d ba

ckgr

ound

10−

5−

0

5

10

15

Eve

nts

/ 20

GeV

1−10

1

10

210

310

410 PreliminaryATLAS


Data

Background-only fit

[GeV]γγm200 400 600 800 1000 1200 1400 1600 1800 2000

Dat

a -

fitte

d ba

ckgr

ound

10−

5−

0

5

10

15

2878 events (mγγ > 200 GeV) 5066 events (mγγ > 200 GeV)

Spin-0 analysis Spin-2 analysis



Event properties in signal region appear similar to those in sidebands, within large statistical uncertainties

Marco Delmastro

] L

ocal

sig

nific

ance

[0

0.5

1

1.5

2

2.5

3

3.5

4

[GeV]X m

200 400 600 800 1000 1200 1400 1600

[%]

X/m

X

0

2

4

6

8

10

ATLAS Preliminary -1 = 13 TeV, 3.2 fbs Spin-0 Selection

X [GeV]G*m

600 800 1000 1200 1400 1600 1800 2000

Pl

M/k

0.05

0.1

0.15

0.2

0.25

0.3 ]Lo

cal s

igni

fican

ce [

0

0.5

1

1.5

2

2.5

3

3.5

Spin-2 Selection-1 = 13 TeV, 3.2 fbs PreliminaryATLASSpin-0 analysis Spin-2 analysis

Background-only p-value scan versus resonance mass and width:

Lowest p-value at ~750 GeV, Γ ~ 45 GeV (6%)

Local / global Z = 3.9 / 2.0σ

Lowest p-value at ~750 GeV, Γ ~ 7% of mass

Local / global Z = 3.6 / 1.8σ

Global p-values derived with respect to scan planes



Compatibility with 8 TeV result (slight reanalysis: latest e/γ calibration, 13 TeV analysis method)

Marco Delmastro

P-value at 750 GeV, Γ ~ 6% of mass: 1.9σ

Compatibility: gg = 4.7 / qq = 2.7 scaling: 1.2σ / 2.1σ

Global p-values derived with respect to scan planes

Eve

nts

/ 20

GeV

1−10

1

10

210

310



Data

Background-only fit

[GeV]γγm200 400 600 800 1000 1200 1400 1600 1800

Dat

a -

fitte

d ba

ckgr

ound

10−

5−

0

5

10

15

• 1 9 σ at m = 750 GeV Γ /m = 6% No significant excessE

vent

s / 2

0 G

eV

1−10

1

10

210

310

410 PreliminaryATLAS


Data

Background-only fit

[GeV]γγm200 400 600 800 1000 1200 1400 1600 1800 2000

Dat

a -

fitte

d ba

ckgr

ound

15−10−

5−05

101520

No excess at 750 GeV

Compatibility: gg / qq scaling: 2.7σ / 3.3σ

Spin-0 analysis Spin-2 analysis


Diphoton resonance searches: ATLASDigression: ATLAS also presented 13 TeV Zγ searches this week

Narrow resonance search, split into Z → and Z → qq final states (qq dominant at high mass).

Background from empirical function

Allison McCarn

Eve

nts

/ 20

GeV

2−10

1−10

1

10

210


-1=13 TeV, 3.2 fbs

DatabBackground-only fit,

[GeV]γJm1000 1500 2000 2500 3000

Dat

a -

b20−10−

01020

Eve

nts

/ 20

GeV

2−10

1−10

1

10

210

310

DatabBackground-only fit,

ATLAS Preliminary

-1=13 TeV, 3.2 fbs

[GeV]γllm200 400 600 800 1000 1200 1400 1600

Dat

a -

b

20−10−

01020

No excess in spectra, limits following expectation

γZ (→ ) γZ (→ qq)


Diphoton resonance searches: CMSUpdated preliminary results presented this week

searches agnostically for spin 0 and 2 bosons. Updated 13 TeV analysis with improved ECAL calibration (~30% improved resolution above mγγ ~ 500 GeV), and including 0.6 fb–1 of B-field off data

Acceptance: ET(γ1/2) > 75 GeV, at least one γ with | | < 1.44 (barrel), split EB-EB, EB-EE

Dedicated calibration of B-field-off data, slightly lower γ-ID efficiency, better resolution, harder PV finding

Empirical background modelling

Pasquale Musella

Eve

nts

/ ( 2

0 G

eV )

1

10

210

Data

Fit model

σ 1 ±

σ 2 ±

EBEB

(GeV)γ γm400 600 800 1000 1200 1400 1600

stat

σ(d

ata-

fit)/

-2

0

2

(13 TeV, 3.8T)-12.7 fbCMS Preliminary

Eve

nts

/ ( 2

0 G

eV )

1

10

210 Data

Fit model

σ 1 ±

σ 2 ±

EBEB

(GeV)γ γm400 600 800 1000 1200 1400 1600

stat

σ(d

ata-

fit)/

-2

0

2

(13 TeV, 0T)-10.6 fbCMS Preliminary

Eve

nts

/ ( 2

0 G

eV )

1

10

210 Data

Fit model

σ 1 ±

σ 2 ±

EBEE

(GeV)γ γm400 600 800 1000 1200 1400 1600

stat

σ(d

ata-

fit)/

-2

0

2

(13 TeV, 3.8T)-12.7 fbCMS Preliminary

Eve

nts

/ ( 2

0 G

eV )

1

10Data

Fit model

σ 1 ±

σ 2 ±

EBEE

(GeV)γ γm400 600 800 1000 1200 1400 1600

stat

σ(d

ata-

fit)/

-2

0

2

(13 TeV, 0T)-10.6 fbCMS Preliminary


Diphoton resonance searches: CMSUpdated preliminary results presented this week

CMS has also looked into event properties of excess region and found them consistent with sidebands

CMS combines 13 TeV with spin-0 and 2 searches from 8 TeV data. Results found to be compatible.

Resulting p-value scans (lowest width models, giving largest excess at 750 GeV, shown here):

Lowest p-value at ~750 GeV (760 for 13 TeV data only), narrow width

Local / global Z = 3.4σ / 1.6σ (2.9σ / < 1 for 13 TeV data only)

(GeV)Sm210×5 310 310×2 310×3

0p-410

-310

-210

-110

J=0-4 10× = 1.4 mΓ

Combined

8TeV

13TeV

σ1

σ2

σ3

(8 TeV)-1 (13 TeV) + 19.7 fb-13.3 fbCMS Preliminary

(GeV)Gm210×5 310 310×2 310×3

0p

-410

-310

-210

-110

J=2-4 10× = 1.4 mΓ

Combined

8TeV

13TeV

σ1

σ2

σ3

(8 TeV)-1 (13 TeV) + 19.7 fb-13.3 fbCMS Preliminary

Pasquale Musella


Alessandro Strumia:

Today it could be everything, including nothing.


Alessandro Strumia:

Today it could be everything, including nothing.

Soon we shall know more.


Moriond EW (51st edition) has been memorable

It exhibited once again the challenges today’s experimental physics takes on and overcomes

The discovery of the Higgs boson required the construction of a huge accelerator and ultra-sophisticated particle detectors to find the events buried under 1012 times larger backgrounds

The direct observation of gravitational waves required to measure over 4 km a relative length deformation two hundred times smaller than the size of a proton.

Similar things can be said about neutrino physics, dark matter searches, etc. It is breathtaking.

Accomplishing these measurements requires great ideas, visionary leadership, long-term support by governments & society, innovative & highest quality hardware and software, computing resources, operational & maintenance support, precise & unbiased analysis — and above all: dedication

Given what we have seen this week, I have no worry. We live in an extraordinary period for fundamental experimental research in physics


Congratulations to the 50th anniversary of Moriond EW & UT.

There will be ample material for an exciting next half a century !


Spare slides


Very short-baseline (reactor) neutrino experiments : SoLidPut neutrino experiment closer to the source to test anti-neutrino flux models

highly segmented plastic scintillation detector coated with Lithium-6, designed to measure flux and energy of anti- e at very short baseline distances between 6–10 m from the compact BR2 test reactor with highly-enriched uranium core in Mol (Belgium).

Challenge is background suppression in proximity of reactor (high captured neutron–e/γ separation) and precise location of IBD products: not only time difference, but also spatial information used to reconstruct IBD events

3 ton SoLid experiment deployed 5.5 m from the BR2 reactor core

Long-term goal: run experiment for three years to resolve reactor neutrino anomaly w/o relying on theoretical calculations. Results with 290 kg prototype presented.

time (16 ns)0 50 100 150 200 250

am

plit

ude (

AD

C c

ount)

-50

0

50

100

150

200

250

300

350

400horizontal fibre

vertical fibre

SoLid preliminary

Example neutron waveform

time (16 ns)0 50 100 150 200 250

am

plit

ude (

AD

C c

ount)

0

100

200

300

400

500

600

700

800horizontal fibre

vertical fibre

SoLid preliminary

Example EM waveform

Nick van Remortel


Of which quantum nature are neutrinos ?EXO-200 showed new limits on neutrinoless double beta decay (0 ββ) in 136Xe → 136Ba + 2e–

enriched (~81%) liquid-xenon TPC (shielded + active muon veto) is installed in nuclear waste isolation plant in New Mexico, US.


2 ββ 0 ββ (LFV)

Requires non-zero Majorana mass term

Γ0 ββ |m |2

mmin [eV]

|mββ

| [

eV]

NS

IS

Cosm

ological Limit

Current Bound

10−4 10−3 10−2 10−1 110−4

10−3

10−2

10−1

1

1σ2σ3σ

100 kg·yr 136Xe exposure:

Lower limit on mMaj( ) = 0.2–0.4 eV (90% CL)

Dominant uncertainty from nuclear matrix element

Lightest mass [eV]

Effe

ctiv

e m

ass,

|m|

[eV

]

m3 lightest

m3 heaviest

oscillation constraints

Yung-Ruey Yen


Of which quantum nature are neutrinos ?CUORE (“heart”) at LNGS is one of several next generation 0 ββ experiments

bolometric technique using array of tellurium dioxide crystals (130Te → 130Xe + 2e–) cooled to ~10 mK → low heat capacity: single particle interaction produces measurable rise in temperature

CUORE-0 (2013–2015): 11 kg 130Te || CUORE (2016–…): 206 kg 130TeSensitivity (detector mass)1/2

Lower limit on mMaj( ) = 0.3–0.8 eV (90% CL)

Reconstructed Energy (keV)2470 2480 2490 2500 2510 2520 2530 2540 2550 2560 2570

Eve

nts

/ (2

keV

)

0

2

4

6

8

10

12

14

16

18/NDF = 43.9/462χ y

r))

⋅ k

g ⋅

Eve

nt R

ate

(cou

nts

/(ke

V

0

0.05

0.1

0.15

0.2

0.25

)σ(R

esid

ual

4−2−024

9.8 kg·yr 130Te exposure (CUORE-0):

Qßß value (2528 keV)

(eV)lightestm4−10 3−10 2−10 1−10

(eV

)ββ

m

4−10

3−10

2−10

1−10

1

(c) 76Ge(a) 130Te (This work)(b) 136Xe

CUORE 90% C.L. sensitivity

IH

NH

CUORE-0 + Cuoricino: T1/20 ββ > 4.0 1024 yr

Paolo Gorla


Cosmological neutrinos: Baryonic Acoustic OscillationsNeutrino physics in the Lyman- forest (2 < z < 5) using BOSS data

offers laboratory with sensitivity to the neutrino mass: free-streaming primordial neutrinos leave their imprint into large-scale structure (LSS) observables:

Set expansion rate at BBN

Suppression of power on small scales probed, eg, by Lyman- forest BAO data

Slow down growth of structure

Reproduce numerically using hydrodynamical models large-structure formation using different neutrino masses.

Combine results on Lyman- forest with CMB (Planck, WMAP, ACT, SPT)

)-1k (h Mpc-410 -310 -210 -110 1

(m

assl

ess)

k (

mas

sive

) / P

kP

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

Level from CMB

Lyman-alpha

= 0.5 eV, z=4ν mΣ

= 0.5 eV, z=2ν mΣ

= 0.5 eV, z=0ν mΣ

= 1.0 eV, z=4ν mΣ

= 1.0 eV, z=2ν mΣ

= 1.0 eV, z=0ν mΣ

Pivot scale

mΩ0.26 0.28 0.3 0.32 0.34 0.36 0.38 0.4 0.42 0.44

ν m

Σ0

0.2

0.4

0.6

0.8

1

1.2 Planck (TT+lowP)

0 + Hα Ly-

+ Planck (TT+lowP) α Ly-

Σm < 1.1 eV (Ly- alone)

< 0.23 eV (CMB, Planck)

< 0.12 eV (Ly- & CMB & BAO combined)

Graziano Rossi

Large list of possible systematic uncertainties


Life in 2015: 13 TeV / 8 TeV inclusive pp cross-section ratio

1 10 100 1000 10000

QBH (6 TeV) QBH (5 TeV)

Q* (4 Tev) Z' SSM (3 TeV)

gluino pair (1.5 TeV) stop pair (0.7 TeV)

A(0.5 TeV, ggF+bbA) ttH ttZ tt

H (VBF) H (ggF)

WH t (t-channel) t (s-channel)

ZZ Z(ll)

W(ln) Minimum bias

9000 370

56 10

46 8.4

4.0 3.9

3.6 3.3

2.4 2.3

2.0 2.5

2.2 2.0

1.7 1.6

1.2 Larger cross section increase for gluon induced than for quark induced processes.

Early Run-2 puts emphasis on searches


New CP violation results in b-hadrons from LHCbApart from the results shown below, new measurements in Lb sector

contributes to vanilla CKM CP physics through various Bd meson measurements

For example: world’s best Δmd from LHCb: 0.5050 ± 0.0021± 0.0010 ps–1 (B-factories: σave = 0.005 ps–1)

Sean Benson

-2 -1 0 1 2 3

BaBarPRD 79 (2009) 072009

0.69 0.03 0.01

BaBar c0 KSPRD 80 (2009) 112001

0.69 0.52 0.04 0.07

BaBar J/ (hadronic) KSPRD 69 (2004) 052001

1.56 0.42 0.21

BellePRL 108 (2012) 171802

0.67 0.02 0.01

ALEPHPLB 492, 259 (2000)

0.84 +-01

.

.80

24 0.16

OPALEPJ C5, 379 (1998)

3.20 +-12

.

.80

00 0.50

CDFPRD 61, 072005 (2000)

0.79 +-00

.

.44

14

LHCbPRL 115 (2015) 031601

0.73 0.04 0.02

Belle5SPRL 108 (2012) 171801

0.57 0.58 0.06

AverageHFAG

0.69 0.02

sin(2 ) sin(2 1)H F A GH F A GMoriond 2015PRELIMINARY

LHCb approaches precision on sin(2 ) from B-factories:

Current picture of corresponding φs

measurements fully consistent with SM

Data-driven studies of penguin pollution using Bs → J/ K* together with SU(3). Excellent experimental precision of < 0.015 on Δφs(J/ φ)


Heavy flavour production at 13 TeV

measured heavy flavour production processes, such as prompt & non-prompt J/ , and B+(→ J/ K+) cross-sections. In agreement with predictions.

[TeV]s5 10

b]μ

[σ

0

5

10

15

20

ψJ/LHCb Prompt

[TeV]s5 10

b]μ

[σ

0

1

2

3

4

-b-fromψJ/LHCb FONLL

σ 1±FONLL,

-b-fromψJ/LHCb FONLL

σ 1±FONLL,

Fiducial region: pT < 14 GeV and 2.0 < y < 4.5

) [GeV]-μ+μ(T

p 5 6 7 8 910 20 30 40 50 60

Non

-pro

mpt

Fra

ctio

n

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0ATLAS Preliminary

, |y| < 0.75-1ATLAS 13 TeV, 6.4 pb

, 0.25 < |y| < 0.50-1ATLAS 7 TeV, 2.1 fb

, |y| < 0.75-1ATLAS 2.76 TeV, 4 pb

, |y| < 0.60-1) 1.96 TeV, 39.7 pbpCDF (p

Non-prompt contribution to total rate rises rise from approximately 25% at pT,μμ of 8 GeV to 65% at 40 GeV

b/G

eV]

μ [T

X)/

dp+

B→

(pp

σd

3−10

2−10

1−10

1

10|<2.4)

BData (13 TeV, |y

|<2.4)B

Data (7 TeV, |y

|<2.4)B

FONLL (13 TeV, |y

|<2.4)B

FONLL (7 TeV, |y

|<2.4)B

PYTHIA (13 TeV, |y

|<2.4)B

PYTHIA (7 TeV, |y

CMS Preliminary (13 TeV)-150.8 pb

) [GeV]± Kψ(J/T

p0 20 40 60 80 100

FO

NLL

σ /

dσd

0.5

1

1.5

2

Diff. cross section for |yB| < 2.4 and √s = 7, 13 TeV

Cross-sections rise mostly due to CM energy; harder pT spectrum at 13 TeV than at 8 TeV

Total σ(pp bb+X ) = 515 ± 2 ± 53 μb

Sanjay Kumar Swain


Documents

Electroweak Interactions & Unified Theories · 2016. 3. 29. · MoriondEW, Mar 19, 2016 Experimental Summary 51st Rencontre de Moriond Electroweak Interactions & Unified Theories