HIGGS ISF HIGGS ISF HIGGS ISF HIGGS Eilam Gross, Weizmann
Institute of Science 1 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross
HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Contributions to SM Higgs: E.
Gozani, A. DiMattia, Y. Rozen (Technion), L.. Barak, M. Pitt, J.
Schaarschmidt, E.G. (Weizmann) & E. Etzion (TAU) [for
continuous support and encouragement in difficult time] The
discovery of the Higgs Boson (July 4 th 2012) occurred after we
submitted the ISF proposal We now celebrate two years to Higgs
discovery. This talk is about the distance we have all gone since
the declaration of Higgs Hunters independence Title of talk should
be modified Searches Precision measurements Mass Signal Strengths
(cross section X BR) Couplings Off-shellness and width Rare decays
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS 2 3 4 ATLAS OLD Recalibration of Layers and gains Muon
momentum calibration Electron and Photon energy calibration Better
and more accurate material description Categories for mass in the
diphoton FSR recovery & corrections BDT-ZZ & per event
errors HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS 5 ID and Services Solenoid Cryostat PS
Calorimeter L1 L2 L3 readout A. David ICHEP 2014 HIGGS ISF HIGGS
ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 6
ATLAS OLD HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS 7 ATLAS OLD HIGGS ISF HIGGS ISF HIGGS 2014,
Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 8 ATLAS NEW ATLAS
NEW Submitted to PRD arXiv: ATLAS CMS HIGGS ISF HIGGS ISF HIGGS
2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 9 10 What do
we measure We measure event yields We want to derive couplings and
signal strengths The first thing we want to measure is the the
signal strength per channel The analysis is using discriminators
(usually reconstructed mass related) to increase S/B 11 HIGGS ISF
HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS What do we measure We measure event yields We want to derive
couplings and signal strengths The first thing we want to measure
is the the signal strength per channel The analysis is using
discriminators (usually reconstructed mass related) to increase S/B
12 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS
HIGGS HIGGS HIGGS What do we measure We increase sensitivity by
classifying the events via categories and measure the signal
strength per category and then combining them taking all the
sytematic and statistical uncertainties into account 13 Loose/tight
high mass 2jet (VBF tag) Phys. Lett. B 726 (2013), pp The
categories are also sensitive to different production modes,
allowing the measurement of the couplings HIGGS ISF HIGGS ISF HIGGS
2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS ttH Probe the
Production Modes Define Parameterize with explicit production modes
and decays Note: ONE CAN ONLY FIT THE PRODUCT We cannot fit
simultaneously the cross section and the BR No full Higgs width fit
is possible to high accuracy at the LHC (from the signal rates) The
categories allow us to fit specific production modes but no
combination is possible unless we make assumptions on the BR 14
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS CMS PAS HIG Probing VBF production mode We fitted
Taking one decay mode at a time we can go one step further and fit
the ratio per channel 15 This ratio is INDEPENDENT of the decay
channel so we can combine HIGGS ISF HIGGS ISF HIGGS 2014, Eilam
Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS ATLAS-CONF CMS PAS HIG
Probing VBF production mode We fitted Taking one decay mode at a
time we can go one step further and fit the ratio per channel 16
This ratio is INDEPENDENT of the decay channel so we can combine
ATLAS-CONF HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Evidence for VBF Higgs Production PROFILING
we can Fit and find an evidence for VBF Higgs production 17 VBF =0
is excluded at 4.1 (ATLAS) VBF =0 is excluded at 3.6 (CMS)
ATLAS-CONF HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS CMS PAS HIG Indirect Sensitivity to Fermion
Couplings Note that if all fermion couplings are set to be equal,
18 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS
HIGGS HIGGS HIGGS Direct observation of H bb and H The Bosonic
channels (,ZZ,WW) provide indirect evidence about the fermion
couplings to Higgs via loops But the direct evidence came with the
observation of the bb and the by (first) CMS and (then) ATLAS 19
H->bb dominates the Higgs total width (BR~58%) ggF,H bb is
saturated with overwhelming direct production of bb from QCD
background The handle is given by a Vector Boson produced in
association with the H bb in the VH,H bb process. With a SM BR of
over 6% and a relatively clean signal in VBF and Boosted
categories, H is even more important then the bb (with the current
luminosity and analysis status) in order to establish the Higgs
direct coupling to fermions. HIGGS ISF HIGGS ISF HIGGS 2014, Eilam
Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Fermions Direct: H bb 20
arXiv: HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Fermions Direct: H Discriminator is not
necessarily mass 21 HH CMSATLAS Signal Strength=0.780.27= Excess3.2
(exp 3.7)4.1 (exp 3.2) ATLAS-CONF arXiv: v1 [hep-ex]ATLAS-CONF
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS ATLAS and CMS each sees a strong evidence for Higgs
coupling to fermions with a strength consistent with the SM
expectation When combined the significance observation goes beyond
5 ATLAS+CMS discovered H Direct Evidence for H Fermions Combining
bb and 22 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Comment: Fermions Direct: ttH Probing the
Higgs Yukawa coupling to top is of an ultimate importance. m top /v
1. Higgs wont decay to tt, but one can probe directly the ttH
coupling by the Higgsstrahlung of Higgs off top or tt fusion to
Higgs, or single top production. The Higgs then decays to bb, hh or
multileptons (from ZZ,WW or ) with extremely small BR. 23 HIGGS ISF
HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS ttH, H bb HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS 24 HIGGS ISF HIGGS ISF HIGGS 2014,
Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 25 Measuring Higgs
Couplings Define the normalized coupling constants (w.r.t. the SM
couplings) HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS 26 Measuring Higgs Couplings Can we resolve
the degeneracy, disentangle The degeneracy can be broken by
parameterize the strength parameters with couplings and introduce
constraints which reduce the number of p.o.i. and allow reasonable
fits. 27 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Disentangling The Couplings 28 The simplest
non-trivial model is (k F, k V ) where all Fermion couplings are
set to k F and all Boson couplings to k V HIGGS ISF HIGGS ISF HIGGS
2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Disentangling
The Couplings Note, couplings are dependent on the Higgs mass In
the (k F, k V ) benchmark: 29 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam
Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Summary of Signal
Strength ATLAS bb is low but with large error. 30 ATLAS-CONF HIGGS
ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS Coupling Benchmarks To make reasonable fits we introduce
physics motivated scenarios. Testing the compatibility of the
discovered Higgs with the SM is to test also where is it NOT
compatible, spotting where NP might sneak in. NP can appear in
either the Higgs width and/or in the loops. 31 HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Probing
Custodial Symmetry WZ is expected to be protected and consistent
with unity Large deviations from 1 indicate new physics. 32 ATLAS
(NP NL ) Overall fZ, k zz profiled CMS (SM) Overall k Z,K f
profiled HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS The Full Monty I : SM Generic Model I
(ATLAS, CMS) All couplings to SM particles are fitted independently
k Z and k W assumed positive, fit is sensitive to sign of k t /k W
-High rate prefers negative k t -The low measured bb rate does not
reflect the sensitivity for k b ATLAS were unlucky -The 5D
compatibility with SM is 14% 33 ATLAS-CONF-HIGG HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS The
Full Monty I : SM 34 ATLAS-CONF HIGGS ISF HIGGS ISF HIGGS 2014,
Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS bb makes 58% of the
Higgs width, bb rate measured low, pulls all couplings down HIGGS
PR HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS
HIGGS HIGGS HIGGS 35 CMS-PAS-HIG Vector and Fermion Couplings The
loop induces some sensitivity to the relative sign between k t and
k W The high observed H ZZ pulls k W up, allowing high rate and
keeps k t positive 36 ATLAS: 2D compatibility with SM 10%
ATLAS-CONF HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Vector and Fermion Couplings This PR plot
tells a story: 37 Tension Drifting apart SM No Tension ATLAS-CONF
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS Vector and Fermion Couplings This PR plot tells a
story: 38 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS Tension Drifting apart SM No Tension Vector
and Fermion Couplings This plot tells a story: 39 HIGGS ISF HIGGS
ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS
Tension Drifting apart SM No Tension Probing the Fermion Couplings
Asymmetry In models BSM (e.g. 2HDM) there is an asymmetry between k
u and k d (u=c,t; d=b,) or k and kq The direct measurement of the
Higgs couplings to b and together with the direct (ttH) and loops
induced coupling to top allows to measure du Measurement of the
coupling to allows a measurement of q The future will bring the
Muons and better ttH into the game and improve the measurement 40
The small asymmetry is from b and t interference in ggH loop A
vanishing coupling to downtype fermions is excluded at the ~3.6(~4)
ATLAS(CMS) ATLAS-CONF HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross
HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Asymmetries in Fermion Sector
CMS are using a SM-like model while ATLAS are using an NP NL model
41 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS
HIGGS HIGGS HIGGS Probing the Beyond (kg,k) 42 HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Probing
the Beyond (kg,k,Br i,u ) 43 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam
Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 44 HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 45 LO
Interf. Interference can resolve sign of k t Far Off Shell domain
STRONG INTERFERENCE Higgs off-shell Physics HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS 46
Assumptions No NP that affects Higgs couplings but not the
continuum Higgs couplings off shell = on shell Far Off Shell domain
LO STRONG INTERFERENCE (=1 in CMS) Higgs off-shell Physics HIGGS
ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS 47 95% CL limit obs. (exp.) OffShell < 6.7 (7.9) CLs
Wondering: Can we do triple Higgs coupling using off-shell Higgs
Physics? HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS 48 Some (still) Rare Decay Channels 49
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS ATLAS-CONF CMS-PAS-HIG CMS-PAS-HIG Differential Cross
Sections 50 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS
HIGGS HIGGS HIGGS HIGGS ATLAS-CONF ATLAS-CONF Highlight t(t)H t(t)
ATLAS-CONF Accidental cancellation of W and t in the di-photon
production loop HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS 51 (Pessimistic) Prospects HIGGS ISF
HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS 52 ATL-PHYS-PUB Real Simulations Extrapolations We will do
(much) better HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS 53 Based on M. Kado ICHEP 2014
Conclusions I 54 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS Conclusions II 55 HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS
Conclusions III In two years the discovery of a scalar particle
compatible with a SM Higgs Boson made a phase transition into
precsion measurements The Higgs moved from the search regime to the
SM regime The last year has proven that reducing the experimental
systematics pays The experiments should focus in understanding the
detector and do better calibrations. IT TAKES TIME! For now in most
important measurements we are statistically limited 56 HIGGS ISF
HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS
HIGGS Finally Current Higgs activities: Technion: VBF H ZZ
(prospective) Weizmann: BSM H + tb, H + combination and 2HDM
interpretations ttH, H , VH, H , H cc (prospective with G. Perez)
TAU: E. Etzion is the new ATLAS BSM Higgs sub-group convener as of
TODAY HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS
HIGGS HIGGS HIGGS 57 Good Luck Erez. BACKUP 58 HIGGS ISF HIGGS ISF
HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS
Discovery Channel H->WW H->WW->lvlv A challenging channel;
No mass reconstruction (mT,mll) Dominant BG WW and tt Understanding
Etmiss tails crucial BG from DATA control regions Analysis in
categories: (0,1,2 jets VBF,VH)X(SF,DF) Most important systematics
from signal cross section (QCD scale, PS and UE, total >10%) 59
Phys. Lett. B 726 (2013), pp CMS: J. High Energy Phys. 01 (2014)
HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS HIGGS HIGGS HIGGS
HIGGS HIGGS 60 HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS A comment on Interference is
extremely important 61 If k t =-1 ggF slightly affected WW
unaffected increases Allowing negative k t is extremely important
Can be probed with tH HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross
HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Measuring Higgs Couplings The
degeneracy of can be broken by parameterize the strength parameters
with couplings and introduce constraints which reduce the number of
p.o.i. and allow reasonable fits. m H =125.5 GeV 62 (t,W)
interference (t,b) interference HIGGS ISF HIGGS ISF HIGGS 2014,
Eilam Gross HIGGS HIGGS HIGGS HIGGS HIGGS HIGGS Uncertainties Width
Measurements HIGGS ISF HIGGS ISF HIGGS 2014, Eilam Gross HIGGS
HIGGS HIGGS HIGGS HIGGS HIGGS 63 L. Quertenmont
