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HCP, Toronto, August 23-27, 2010
Other experiments at LHC:
LHCf, MoEDAL, Totem
Oscar AdrianiUniversità degli Studi di
FirenzeINFN Sezione di Firenze
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
David(s) vs Goliath
But also David(s) are able to do very good physics!!!!
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
‘Traditional style’ particle physics detectorOnline DAQ systemLocated in the forward/very forward region
Nuclear Track Detector based experimentDetector is:
• Exposed• Removed• Off-line analyzed
Totem
LHCf
MoEDAL
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf & Totem
Dedicated forward/very forward experiments
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
How to access Forward/Very Forward Region at LHC?
Charged particles
Neutral particles
Beam pipe
Surrounding the beam pipe far away from IP with detectorsSimple way, but still miss very very forward particles
Approach #1 used by Totem
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Neutral particles
Beam pipe
Charged particles
Install detectors (movable!) inside the beam pipe very far away from the IPChallenging but ideal for charged particle
How to access Forward/Very Forward Region at LHC?
Approach #2 used by Totem
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Detectors can be installed where the single beam pipe splitsIn 2 separate beam pipes, 140 m away from the IPAll neutral particle produced can be measured
Charged particles
Neutral particles Beam pipe
How to access Forward/Very Forward Region at LHC?
Approach used by LHCf (and in general by the others Zero Degree Calorimeters)
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Pseudo rapidity coverage at LHC
Pseudorapidity: = - ln (tan/2)
All phase space covered thanks to dedicated forward detectors!And most of the energy is concentrated in the forward regions!
Particle flow
Energy flow
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
TotemTotem
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T1:3.1 << 4.7
T2: 5.3 < < 6.5
T1 T2 CASTOR (CMS)
Roman Pot @147 m Roman Pot @220 m
10.5m
14m
Totem experimental layout
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T1 TelescopeT1 TelescopeCathode Strip Chambers (CSC)3.1 < || < 4.75 planes with measurement of three coordinates per plane, ~ 1 mmPrimary vertex reconstruction (beam-gas interaction removal)Trigger with anode wires
Both arms are completely assembled and equipped in the test beam line H8.
Successfully tested with pion and muon beams in May – June 2010Both telescope arms not yet installed but ready for installation
chamber frames
~3 m
1 arm
stripstrip
wire
0.8 1.1 m
¼ of T1
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2 Telescope Gas Electron Multiplier (GEM) 5.3 < || < 6.5 10 half-planes @ 13.5 m from
IP5 Half-plane:
512 strips (width 80 µm, pitch of 400 µm), radial coordinate
65*24=1560 pads (2x2 mm2 -> 7x7 mm2), radial and azimuth coord.
Resolution: (R) ~ 100 µm, () ~ 1°
Primary vertex reconstruction (beam-gas interaction removal)
Trigger using (super) pads
All T2 chambers on both sides of IP5 installed and operational (data & trigger)
40 cm
pads
strips
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2: Preliminary Distribution
(with detector efficiency)
T2 acceptance
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
14
Roman PotsRoman PotsMeasurement of very small proton scattering angles (few µrad)Vertical and horizontal pots mounted as close as possible to the beamBPM fixed to the structure gives precise position of the beam
All 12 Roman Pots at ±220 m from IP5 are operational (data with active triggers)RP147 detector assemblies to be installed during next winter technical stop.
HALF OF THE RP STATION
Horizontal RP Vertical RP BPM
Roman Pot
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
RP alignment w.r.t. the Beam Centre
• Alignment is the central problem of Roman Pot measurements:– Done at 450 GeV on the 25th of June 2010
• LHC collimation system produces sharp beam edges:– used to align Roman Pots and to determine the centre of the beam– same procedure as collimator setup
• When both top and bottom pots “feel” the edge:– they are at the same number of sigmas from the beam centre as the
collimator– the beam centre is exactly in the middle between top and bottom
pot Collimator cuts a sharp beam edge
symmetrically to the centre
RP approaches this edge
until it scrapes …
… producing spike in BLM downstream
The second RP approache
s
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Totem Physics plans• Early physics plan (2010-2011)
– Physics at s 7 TeV with low * (= 2 - 5 m) optics: • forward charge particles studies with T2• large |t| elastic scattering• high mass SD & CD
– Physics at s 7 TeV with short * = 90 m runs:• early measurement of tot @ 5-6 % • elastic scattering in wider |t|range (|t| > 0.015 GeV2)• SD & CD @ any M• classification of inelastic events:
– inelastic rates– process dependent forward charged multiplicity
• Full physics plan– TOTEM
TOTpp with a precision ~ 1-2%
• Elastic pp scattering in the range 10-3 < |t| ~ (p)2 < 10 GeV2
• Soft diffraction (SD and DPE)• Particle flow in the forward region (cosmic ray MC
validation/tuning)
– TOTEM & CMS• Soft and hard diffraction in SD and DPE (production of jets, bosons,
h.f.)• Central exclusive particle production• Low-x physics• Particle and energy flow in the forward region
Total cross-section
Elastic Scattering
b
Diffraction: soft and hard
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
p-p Total Cross Sectionp-p Total Cross Section
RPT1&T2
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
High * optics needed to measure the total pp cross-sectionEarly optics:*=90m (un-squeezing of existing injection optics, |t| > 3 102 GeV2)
Target optics:*=1540m (difficult to have at the beginning – requires special injection optics)
acceptance at very low |t| > 2 103 GeV2
1.5x106
2x109
500
30
1
4000
0.3
* = 90 m
* = 11 m
* = 2 m
11m
90m
1540m
exponential region
Elastic scatteringElastic scattering, exponential , exponential partpart
BSW
*=90m∫Ldt= 0.3pb-1
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Experimental set-upExperimental set-up
Detectors installed in the TAN Detectors installed in the TAN region, 140 m away from the region, 140 m away from the Interaction Point 1Interaction Point 1Here the beam pipe splits
in 2 separate tubes.Charged particle are swept away by magnets Coverage up to
Charged particlesCharged particles
Neutral particlesNeutral particles
Beam pipeBeam pipe
ProtonsProtons
INTERACTION POINTINTERACTION POINT
IP1 (ATLAS)IP1 (ATLAS)
Detector IIDetector II
TungstenTungsten
ScintillatorScintillator
Silicon Silicon stripsstrips
Detector IDetector I
TungstenTungsten
ScintillatorScintillator
Scintillating Scintillating fibersfibers
140 m140 m 140 m140 m
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
40mm
20mm
25mm
32mm
The LHCf detectors
Expected Performance Energy resolution (> 100GeV) < 5% for photons 30% for neutrons Position resolution < 200μm (Arm#1) ~40μm (Arm#2)
Sampling and Position-measurement Calorimeters • W (44 r.l , 1.7λI ) and Scintillator x 16 Layers• 4 position measurement layers XY-SciFi(Arm1) and XY-Silicon strip(Arm#2)• Each detector has two calorimetric towers, to allow the 0 reconstruction
Front Counter• Thin scintillators 80x80mm2 to monitor beam condition. • For background rejection of beam-residual gas collisions by coincidence analysis
Arm2Arm2
Arm1Arm1
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
ATLAS & LHCf
Goliath
David
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
HECR Open Issues
Difference in the energy scale between different experiments???
AGASA Systematics
Total ±18%Hadr Model ~10% (Takeda et al., 2003)
AGASA Systematics
Total ±18%Hadr Model ~10% (Takeda et al., 2003)
M NaganoNew Journal of Physics 11 (2009) 065012
The depth of the maximum of the shower Xmax in
the atmosphere depends on
energy and type of the primary
particle
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
AlessiaTricomi AlessiaTricomi University and INFN University and INFN
CataniaCatania
Development of atmospheric showersDevelopment of atmospheric showers
LHCLHC
TevatronTevatron
A 100 PeV fixed-target interaction with air has the cm energy of a pp collision at the LHC
AUGERAUGER
Cosmic ray spectrumCosmic ray spectrum
Determination of E and mass of Determination of E and mass of cosmic rays depends on cosmic rays depends on description of primary UHE description of primary UHE interactioninteraction
Hadronic MC’s need tuning with dataHadronic MC’s need tuning with dataThe dominant contribution to the The dominant contribution to the energy flux is in the energy flux is in the very forward very forward region (region ( 0)0)
In this forward region the highest In this forward region the highest energy available measurements of energy available measurements of 00 cross section done by UA7 cross section done by UA7 (E=10(E=101414eV, y= 5÷7)eV, y= 5÷7)
LHCf: use LHCLHCf: use LHC√√s = 14 TeVs = 14 TeVEElablab=10=101717eVeV to calibrate MCsto calibrate MCs
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
γ
nπ0
Energy spectra and transverse momentum distribution of
• (E>100GeV,E/E<5%)•Neutral Hadrons (E> few 100 GeV, E/E~30%)• 0 (E>700GeV, E/E<3%)
in the pseudo-rapidity range >8.4
What LHCf can measure?
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf operation in 2009 & 2010
With Stable Beam at 450 +450 GeV • 42 hours for physics• ~100,000 showers events in Arm1&Arm2
With Stable Beam at 3.5+3.5 TeV150 hours for physics with different setups
Vertical positionBeam crossing angle
~4.108 showers events in Arm1&Arm2~106 0 events in Arm1&Arm2
LHCf completed operation at 900GeV and 7TeV The detectors were removed from the LHC tunnel on 20/07/10 The detectors will be re-installed for operation at 7TeV+7TeV in 2013 after the upgrade of the detector for radiation improvement
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Impressive TeV Shower
X Transverse projection
Y Transverse projection
Longitudinal projections
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Spectra at 900GeV
preliminary preliminary
preliminarypreliminaryGamma-ray likeGamma-ray like
Gamma-ray likeGamma-ray like Hadron likeHadron like
Hadron likeHadron likeArm1Arm1
Arm2Arm2
Spectra are normalized by number of gamma-ray and hadron like events Detector response for hadrons and systematic errors (mainly absolute energy scale) are under study.
Only statistical errors are shown
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
0 reconstruction @ 7 TeV
ΔM/M=2.3%
Reconstructed mass @ Arm2
Measured 0 energy spectrum @ Arm2
preliminary
preliminary
An example of 0 event
0’s are a main source of electromagnetic secondaries in high energy collisions.
The mass peak is very useful to confirm the detector performances and to estimate the systematic error of energy scale.
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
search
0 Candidates
Candidates
• ratio vary a lot among different interaction models. A good handle to probe the hadron interaction models• Another calibration point for more robust energy scale
preliminary
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Moedal
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Searching for Magnetic Monopoles
MM energy loss
From the experimental point of view:Very highly ionizing particle!
Extended search up to now done both at accelerators and in CR
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
MoEDAL is located in the LHCbIP, covering the VELO cavern
MoEDAL: Monopole search at LHC: ppppMM
Operating procedure:1) Expose the detector2) Remove it3) Chemical etching to
create the etched cones4) Scan the etched plates
searching for aligned holes, pointing to the IP (x~1cm)
Plastic track edge detector based experiment
mm
m
25 m2 in total
A test detector is already installed
The full MoEDAL will be installed in the next LHC shutdown
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Physics Reach for MM Production
Drell-Yan cross-section for magnetic-monopole pair production at the LHC
Exclusion curve for 10fb-1 ( x acceptance=30%)
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Conclusions• Interesting physics cases can be studied also
with ‘David like’ detectors optimized for specific measurements– Totem: tot and Diffraction
– LHCf: MC tuning for Cosmic Rays experiments– MoEDAL: Monopole search
• Full support from Cern and LHCCThanks!• Nice physics results are already coming and
more exciting ones will certainly come in the near future
• P.S: Please note: David and Goliath are not ennemies, but nice friends!!!!!
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Backup slides
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf : Monte Carlo discrimination @ <14 TeV
γ
n
γ
n
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Particle Identification
L90% @ 20mm cal. of Arm1
MC (QGSJET2)Data
Preliminary
Thick for E.M. interaction (44X0) Thin for hadronic interaction(1.7)
A transition curve for Gamma-ray A transition curve for Hadron
Definition of L90%
Gamma-rays:L90%<16 r.l. + 0.002 x dE
Gamma-ray like
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Alessia Tricomi Alessia Tricomi University & INFN University & INFN
CataniaCatania
The LHCf experiment at LHC The LHCf experiment at LHC ISVHECRI08, Paris 1-6 ISVHECRI08, Paris 1-6 September 2008September 2008
Radiation Damage StudiesRadiation Damage Studies
30 kGy30 kGy
•Expected dose: 100 Gy/day at 10Expected dose: 100 Gy/day at 103030 cm cm--
22ss-1-1
•Fewmonths @ 10Fewmonths @ 103030 cm cm-2-2ss-1-1: 10 kGy: 10 kGy• 50% light output50% light output•Continous monitor and calibrationwith Continous monitor and calibrationwith
Laser system!!!Laser system!!!
Scintillating fibers and scintillatorsScintillating fibers and scintillators
1 kGy1 kGy
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
0.5mm
Thin window 0.150mm
10 planes of edgeless detectors
Roman Pot detectors
Beam
Leading proton detection at distances down to 10×(beam) + d
Need “edgeless” detectors that are efficient up to the physical edge to minimize “d”
(beam) ≈ 0.10.6 mm (optics dep.)
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
28/04/2009 Hubert Niewiadomski, TOTEM
50
µm
66 μm pitch
dead
are
a
Planar technology with CTS(Current Terminating
Structure)I2I1
+-
biasing ring Al
p+
n+
cut edge
current terminating
ring
Al
SiO2
n-type bulkp+
50µm
Si Edgeless Detectors for Si Edgeless Detectors for RPRP
AC coupled microstrips made in planar AC coupled microstrips made in planar technology with novel guard-ring design and technology with novel guard-ring design and biasing schemebiasing scheme
Readout with VFAT chipsReadout with VFAT chips LLeakage current : 60 nA at 200 V (excellent)eakage current : 60 nA at 200 V (excellent) All producedAll produced Installation ongoing: RP220 (147) fully (partially) Installation ongoing: RP220 (147) fully (partially)
equipped by Juneequipped by June
3.5 cm
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
RP alignment @ 450 GeV
BLM @ 221 mBLM @ 225 m
Start with primary collimator at 4.9 beam edge at 4.9
RP approach (in ≥100m steps)Beam Loss Monitor (BLM)
RP trigger rate
RP 4-5 (-220m) Near – TOP @ 4.9
RP 4-5 (-220m) Near–BOTTOM @ -4.9
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
A Single Track Event in RP
Near Far
Top Top
Horizontal
Bottom Bottom
Horizontal
transverse view
Top
Hor.
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2 event @ 7TeV
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHC OpticsLHC Optics
– momentum loss
Proton position at RP (x*, y*) is a function of position (x*, y*) and divergence (x
*, y*) at IP:
Beam size and beam divergence at IP5 and at RP
spread of the primary vertex, beam size at RP
beam divergence at IP5 limits the angle measurement precisionx
Proton acceptance is determined by • optical functions, mainly Lx, Ly, Dx
• beam size x, y at RP• internal LHC apertures
RP IP5
measuredreconstructed
RP det.IP5
proton
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Combined Combined uuncertainty in ncertainty in tottot
* = 90 m 1540 m• Extrapolation of elastic cross-section to t = 0: ± 4 % ± 0.2 % (Smearing effects due to beam divergence, statistical errors, uncertainty of effective length Leff, RP alignment, model dependent deviations)
• Total elastic rate (strongly correlated with extrapolation): ± 2 % ± 0.1 %• Total inelastic rate: ± 1 % ± 0.8 %
(error dominated by Single Diffractive trigger losses)• Error contribution from (1+2): ± 1.2 %
* = 90 m required for early * = 90 m required for early tottot measurement during the first measurement during the first year of LHC running at 7 TeVyear of LHC running at 7 TeV
Total uncertainty in Total uncertainty in tottot : : ± 5% ± 1÷2 %
Total uncertainty in Total uncertainty in L : L : ± 7 % ± 2 %
20
1
/16 el t
elto
nt
i el
dN dt
N N
2
0
21
/16el inel
el t
N N
dN dt
L
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
48
T1&T2 + RP provide fully inclusive trigger:
Primary vertex reconstruction to discriminate against beam-gas interactions
TOTEM Trigger efficiency: SD: 82 %, NSD > 99 %
InelasticInelastic event rate event rate NNinelinel
Single Diffractive
Trigger:
Double Diffractive
Trigger:
Central Diffractive
Trigger:
Minimum BiasTrigger:
p
p
p
T1/T2RP RPCMS
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
TOTEM diffractive TOTEM diffractive protonsprotons’ ’ acceptanceacceptance
Log(-t/GeV2)
Lo
g(-)
Lo
g(-)
Lo
g(-)
Log(-t/GeV2)Log(-t/GeV2)
7 TeV, *= 1535 m7 TeV, *= 90 m
low *
low * : 0.5 – 2 m, L 1033 cm-2s-1
early running: E = 5TeV, * = 3 m
elastic acceptance2 GeV2 < -t < 10 GeV2
resolution() = 16 – 30 µrad() = 1 – 6 10-3
- > 2 % seen
(hard) diffraction, high |t| elastic scattering
* = 90 m
L 1030 cm-2s-1
elastic acceptance3 10-2 GeV2 < -ty < 10 GeV2
resolution() = 1.7 µrad
() = 6 – 15 10-3
all seen, universal optics
diffraction, mid |t| elastic scattering, total cross-section
* = 1535 m
L 1028 – 1029 cm-2s-1
elastic acceptance2 10-3 GeV2 < -ty < 0.5 GeV2
resolution() = 0.3 µrad
() = 2 – 10 10-3
all seen
total cross-section, low |t| elastic scattering
28/04/2009 Hubert Niewiadomski, TOTEM
5TeV, *= 3 m
prelim.
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Calibration of MoEDAL NTDs
MoEDAL NTDs have excellent charge resolution
Calibration is performed using heavy -ion beam
• Calibration at high energy heavy-ions sources is preferred eg BNL, CERN• But if these sources are unavailable low energy ion sources can be used eg:
– CHIBA Japan - 300-400 NeV/nucleon– Low energy heavy-ion soures at University de Montreal
• The MoEDAL Collaboration has experience with both types of calibration
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Backgrounds• The important background source are nuclei from spallation products from
secondary interactions of particles produced in the primary interaction. – Such interactions take place with nuclei in the material of the detector and the
material surrounding and including the beam pipe.
– Interactions of the colliding beams with residual gas atoms in the beam pipe can also produce highly ionizing spallation products.
• The above sources of background are severely reduced in NTD arrays. Here is how:– The two track resolution of NTDs is extremely good, of the order of 10μms.
Reducing overlap buildup.
– The threshold of CR39, the most sensitive of the NTDs employed by MoEDAL - corresponds to a Z/
• Use of different plastics with different thresholds - Makrofol has a factor of 100 smaller sensitivity to spallation background than CR39
– The requirement of aligned etch pits in a several NTD sheets
– Track pointing to IP to an accuracy of ~1cm
– The different energy loss signature of the Monopole, or highly penetrating electrically charge particles, gives a clear distinction over a stopping spallation product