lhcf status report
DESCRIPTION
LHCf status report. Oscar Adriani Università degli Studi di Firenze INFN Sezione di Firenze. Experimental set-up. Protons. Charged particles. 140 m. 140 m. Neutral particles. γ. 8 cm. 6 cm. Beam pipe. n. γ. π 0. Detector I Tungsten Scintillator Scintillating fibers. - PowerPoint PPT PresentationTRANSCRIPT
Parma, 23 Settembre 2010
LHCf status report
Oscar AdrianiUniversità degli Studi di
FirenzeINFN Sezione di Firenze
Oscar Adriani 23/09/10
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 We cover up to y
INTERACTION POINT
IP1 (ATLAS)
Detector II
Tungsten
Scintillator
Silicon strips
Detector I
Tungsten
Scintillator
Scintillating fibers
Charged particlesCharged particles
Neutral particlesNeutral particles
Beam pipeBeam pipe
ProtonsProtons
140 m 140 m
n π0
γ
γ8 cm 6 cm
Oscar Adriani 23/09/10
LHCf : Monte Carlo discriminationLHCf : Monte Carlo discrimination
106/107 generated LHC interactions at 7+7 TeV 1 minute exposure@1029 cm-2s-1 luminosity
n
Oscar Adriani 23/09/10
LHCf Operations at 900 GeV06 Dec – 15 Dec 2009
27.7 hours for physics
~5x105 collisions at IP1
~2,800 shower events in Arm1
~3,700 shower events in Arm2
02 May – 27 May 201015 hours for physics
~5.5x106 collisions at IP1 (Statistics x 11 wrt 2009)
~44,000 shower events in Arm1~63,000 shower events in Arm2
Beam Gas significantly reduced wrt 2009
Oscar Adriani 23/09/10
2009 vs 2010
2009 2010
Very big reduction in the Beam Gas / Bunch crossing ratio!!!!Very big increase of the ‘signals/noise’ ratio due to higher intensity
Oscar Adriani 23/09/10
Arm1 Spectra at 900 GeV
MC normalized to the total number of events in the 2 towers,without PID.Only one normalizationfactor common to all models
Preliminary
Only statistical errors are quoted
Oscar Adriani 23/09/10
Arm2 Spectra at 900 GeV
MC normalized to the total number of events in the 2 towers,without PID.Only one normalizationfactor common to all models
Preliminary
Preliminary
Only statistical errors are quoted
Oscar Adriani 23/09/10
LHCf 2010 runs (mainly at 7 TeV)
• Detector shows good performance with stable quality.– Energy scale calibration with the 0 peak!!!!– Good stability < ±1% level. – We started to have some radiation problems in the
last periods.
• Thanks a lot to all LHC people for providing us 100 rad crossing angle!!! – Very important for physics to enlarge the PT
acceptance
• Detectors were removed on July 20, 2010
Oscar Adriani 23/09/10
Acceptance gain due to Crossing Angle
Arm1Arm1
No crossing angle 100 rad crossing angle
A very significant gain in acceptance is clearly visible!
Oscar Adriani 23/09/10
Operation at 7 TeVWithout crossing angle (30/03 – 05/06)With 100rad crossing angle (25/06 – 20/07)
Runs are taken in many different vertical position and with/without Xing angle
Oscar Adriani 23/09/10
7 TeV collisions
Y-view of silicon strip
X-view of silicon strip
Transition curve in towers
1 TeV gamma-ray shower @ Arm2
Oscar Adriani 23/09/10
0 at 7 TeV
Arm2 event display
Silicon layers
Scintillator layers
To
wer
32m
m
25m
m
Robust sample Good energy calibrator
25 mm tower
32 mm tower
Oscar Adriani 23/09/10
Beam position analysis: LHCf vs BPM
Oscar Adriani 23/09/10
M/M=6.3MeV/135MeV=4.7%
0 mass and energy spectrum (Arm1)
Please note the Very High Energy!
Preliminary
Preliminary
Preliminary
Oscar Adriani 23/09/10
0 mass and energy spectrum (Arm2)
M/M=2.3%
Using only data taken before April 13th
Preliminary
Preliminary
Oscar Adriani 23/09/10
Particle ID: L90%
Oscar Adriani 23/09/10
PID study Energy spectra with not PID biasedEnergy spectra with not PID biased
By fitting the L90% distribution with the superposition of 2 components (gamma-rays and hadrons), the efficiency and purity can be estimated from the data themselves.
Before the correctionAfter the correction
Oscar Adriani 23/09/10
Measured Spectra at 7TeV
preliminary preliminary
Gamma-ray likeGamma-ray likeHadron likeHadron like
Arm2Arm2
preliminarypreliminaryGamma-ray likeGamma-ray like Hadron likeHadron likeArm1Arm1
Very high statistics !! only 2% of all data
Oscar Adriani 23/09/10
Arm1/Arm2 Comparison
Red : Arm1Blue : Arm2
Red : Arm1Blue : Arm2
• Same geometrical regions and same runs are selected
• Correction for different livetimes
Oscar Adriani 23/09/10
search
All data taken with zero-crossing angle and low luminosity
In the High Lumi/High Pile Up runs we don’t see (combinatorialbackground)
Oscar Adriani 23/09/10
Luminosity with VdM scan with Front Counter Data
σx & σy are measured in VdM scan (May 9th)
independently from interaction model or detector
Calculate luminosity with this VdM scan
Calculate “FC rate Luminosity” Conversion Factorto be independent from MC
L f revnbN1N2
2 x y
Oscar Adriani 23/09/10
VdM scan May 9th, 2010 FC rate of arm1 / 1000
Beam position - start of scan +0.3mmBeam position - end of scan +0.3mm
Scan FC1 FC2 FC1&2 ATLAS
Scan 005
59.8μm 59.9μm 58.4μm 59.1μm
Scan 006
60.0μm 60.3μm 59.1μm 59.3μm
x measured by FC
Horizontal scan
Lumi measured perfectly compatible with Atlas!
+
Oscar Adriani 23/09/10
Radiation Damage
3%
Dose measured by the dosimeters behind the calorimeters
0 mass peak
Oscar Adriani 23/09/10
LHCf removal• LHCf has completed the basic physics
program at 7 TeV • LHCf has been removed on July 20th,
during a short technical stop (a little bit
)
• Laser calibrations were done for few weeks after the removal (Annealing)
• Test beam is foreseen from October 15 to 28– 3 days main users– 10 days parasitic run
Oscar Adriani 23/09/10
Future activities (I)
2011 – Replace plastic scintillators with Rad Hard
GSO (prepared by Japan side) in Florence Clean Rooms
– Produce 2 new silicon modules to replace partly defective ones + 2 spares
– Modify the silicon layers positions to improve silicon-only energy resoution
– Test beam at SPS to calibrate Arm1&Arm2– Test beam at GSI to intercalibrate the Silicon
Pace3 response with relativistic High Z Nuclei
Oscar Adriani 23/09/10
R&D for the detector upgrade.
Plastic scintillators (EJ260)Plastic scintillators (EJ260) ⇒ ⇒ GSO scintillators GSO scintillators
EJ260
Radiation damage measured by Ion beams
Scintillating Fibers ⇒ GSO bars
MIP peak
Oscar Adriani 23/09/10
New silicon layers arrangement
8 Silicon Layers 6 6 12 12 18 26 34 42 X0
Oscar Adriani 23/09/10
Future activities (II)• 2012
– Install the detectors at RHIC?– RHIC can accelerate:
• p-p up to 250 GeV/nucleon• Ions up to 100 GeV/nucleon• They have already done deuteron-Gold• They could do p-Light ion
– RHIC beam pipe arrangement• Situation similar to LHC• Single beam pipe split in 2 at 20 m from IP• Space available ~ 10 cm• LHCf can fit very well inside!
– 0 can be reconstructed as we are doing in LHC!
• Sqrt(s)min=4 m d/hdet • d=20 m, hdet = 8 cm Sqrt(s)min= 135 GeV
• More news in 2011—> Stay tuned!!!!!!!
Oscar Adriani 23/09/10
Future activities (III)
• 2013-2014 – Re-install Arm1&Arm2 at LHC when the
energy will be raised to 13/14 TeV– Necessity to mantain the Cern
infrastractures:• Control room• Electronics pool material• Safety infrastructures• Racks in underground areas• Team account• Etc. etc. etc.
Oscar Adriani 23/09/10
Conclusion
• LHCf has completed the basic physics program at 7 TeV
• LHCf was removed from TAN on July 20th, 2010• Test beam is foreseen in October 2010 • The detector will be upgraded during 2011 to
improve radiation hardness– GSO will replace plastic scintillator– More energy measurement oriented silicon
arrangement
• RHIC Option for 2012? Stay Tuned!!!!!!!!!!• LHCf will certainly be back in the TAN for the
14 TeV run!
Oscar Adriani 23/09/10
Backup slides
Oscar Adriani 23/09/10
Studies of detector responses
layer
dE
MC (DPMJET3)Measured
Silicon Tracker
LHCf Detector
Beam Pipe
Transition curve for 350GeV/c protonsDetector response for hadrons Detector response for hadrons by beam test data at SPS done in 2007by beam test data at SPS done in 2007
LPM effectLPM effectThe radiation length for high energy particles seems to become longer in the heavy matter. - Confirmation of the LPM effect - Effect to the energy reconstruction and PID etc.
Transition curve for 1.5TeV γ (MC)
presented by SAKO
protons with 350GeV/c and 150GeV/c⇔ LHC: 450GeV+450GeV
Presented by MASE
Oscar Adriani 23/09/10
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 23/09/10
Particle Identification
Thick for E.M. interaction (44X0) Thin for hadronic interaction(1.7)
Longitudinal development of shower Longitudinal development of Hadron shower
Definition of L90%
Gamma-rays:L90%<16 r.l. + 0.002 x dE
Oscar Adriani 23/09/10
Results at 900GeV: PID
Gamma-rays:L90%<16 r.l. + 0.002 x dE
QGSJET2
Data
QGSJET2
Data
QGSJET2
Data
QGSJET2
Data
Preliminary
Oscar Adriani 23/09/10
L90%<18X0
Constant cut
Oscar Adriani 23/09/10
RHIC Physics Case
• p-Light Ion– This measurement will allow to directly
measuring the characteristic of the HECR-atmosphere interactions, without having to rely on the approximation usually done to go from the p-p collision to the p-nucleus collision (Glauber approximation).
• p-p – We propose also to run the RHICf experiment
in the p-p collisions, to have the possibility to directly check the validity of the Glauber approximation at 200 GeV center of mass energy by comparing the p-p with the p-LI results.
Oscar Adriani 23/09/10
Beam Position Analysis from the LHC data
Theoretical center
Positive; upward in V outward in H
43m140m
BPMSW
BPMSWIP Offset; bθ
• Beam position (b) and angle (θ) can be determined from the measurements of two BPMSW (beam position monitor)
• Expected position (neutral center) on the LHCf detector at 140m away can be calculated from these numbers
• Analysis done by Simon White
Oscar Adriani 23/09/10
FrontCounter as a good luminosity monitor
• FC is working very well for luminosity monitoring (Very useful monitor for the machine)
• Continuous monitoring w/ independent DAQ now available. See Page1 “LHCf experiment”
• Conversion to “luminosity” from FC rate is now under study by MC
Beam pipe
TANNeutral particles
FCLHCf-CAL
BR
AN
-Sci
ZD
CZ
DC
ZD
CB
RA
N-I
C
Gaussian fit
Arm1
Arm2
Coincidence
Stay all the time
lumiscan
Page1LHCf page
Oscar Adriani 23/09/10
ATLAS online (w/o calibration)
VdM scanning