Muon Trigger Muon Trigger and Physical and Physical Processes Processes with Hard Muons with Hard Muons at a Collider at a Collider Experiment Experiment V. Palichik Joint Institute for Nuclear Research Dubna NEC’2003 Varna, Bulgaria 15 September, 2003
15
Embed
Muon Trigger and Physical Processes with Hard Muons at a Collider Experiment
Muon Trigger and Physical Processes with Hard Muons at a Collider Experiment. V. Palichik Joint Institute for Nuclear Research Dubna. NEC’2003 Varna, Bulgaria 15 September, 2003. Study of Processes with Hard Muons. 2007: start of 14 TeV LHC - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Muon Trigger Muon Trigger and Physical Processes and Physical Processes
with Hard Muons with Hard Muons at a Collider Experimentat a Collider Experiment
V. PalichikJoint Institute for Nuclear Research
Dubna
NEC’2003
Varna, Bulgaria
15 September, 2003
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Study of Processes with Hard MuonsStudy of Processes with Hard Muons
2007: start of 14 TeV LHC
An interest to An interest to search heavy resonances (search heavy resonances (ZZ, W, W, g, gkkkk) ) in TeV region:in TeV region:
C.-E.Wulz “Z at LHC”, CMS-TN/93-107.
P.Traczyk, G.Wrochna “Search for Randall-Sundrum Gravition Excitations in the CMS Experiment”, CMS Note 2002/003.
C.Alexa “Prospects for Exotic Physics at the LHC”, ATL-CONF-2001-005.
D.R.Tovey “Searches for New Physics at the LHC”, ATL-CONF-2002-005.
I.Golutvin, P.Moissenz, V.Palichik, M.Savina, S.Shmatov “Search for
TeV-scale bosons in the +- decay channel in CMS”, reported at Conf. ”Physics at LHC”, Prague, July, 2003.
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
An eхаmple of di-muon event (Pt of muons ~ 1 TeV)
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Identification and reconstruction of TeV Identification and reconstruction of TeV muons on L1 and L2 trigger levelsmuons on L1 and L2 trigger levels
L1 reconstruction of TeV muons in CSCs:L1 reconstruction of TeV muons in CSCs:
Pt, GeV
N events
Pt ( L1 )
The principle of working of a Cathode Strip The principle of working of a Cathode Strip ChamberChamber
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Cathode Local Charge Track (CLCT) in CSC Cathode Local Charge Track (CLCT) in CSC
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
N layerN layer ADC
11
22
33
44
55
66N strip
1/21/2–strip algorithm –strip algorithm on 6 layerson 6 layers
Level-2 Algorithm for Muon ReconstructionLevel-2 Algorithm for Muon Reconstruction
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
L1 muon trigger data provides (eta-phi)-L1 muon trigger data provides (eta-phi)-region for muon track searching;region for muon track searching;
track-segments building in a given (eta-track-segments building in a given (eta-phi)-region for each chamber;phi)-region for each chamber;
L2 trajectory seeding (position and L2 trajectory seeding (position and momentum) on a base of L1 muon tracks;momentum) on a base of L1 muon tracks;
track reconstruction using Kalman filter track reconstruction using Kalman filter technique.technique.
An example of L1&L2 reconstruction An example of L1&L2 reconstruction of a simulated 1 TeV muon event in CSCsof a simulated 1 TeV muon event in CSCs
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Drawn by Ivan Belotelov, JINR
cm
rad
z - projection
z - projection
Z, cm
Z, cm
generated muon
* CLCTs
L1 reconstruction
L2 reconstruction
CSC hits
CSC track segments
CSC hits used for L2 reco
++ Kalman filter propagation states
Standard object-oriented reconstruction
Pt(gen)=1000 GeV
Pt(L1)= 6 GeV
Pt(L2)= 5 GeV
Reconstructed Pt (L2) distribution Reconstructed Pt (L2) distribution for 1 TeV muons for 1 TeV muons
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Standard object-oriented reconstruction
The results obtained in cooperation with Ivan Belotelov
Pt, GeV Pt, GeV
Modification of L2 reconstruction algorithm Modification of L2 reconstruction algorithm for TeV muons in CSCsfor TeV muons in CSCs
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
The modifications of the algorithm have been The modifications of the algorithm have been created in cooperation with Ivan Belotelovcreated in cooperation with Ivan Belotelov
1. The algorithm of track segment building has been improved with taking into account the contamination of muon measurements by a secondary electromagnetic accompaniment.
2. New L2 trajectory seeding on a base of the best track-segment selection (on criteria) in a wide L1 -region has been proposed.
An example of L1&L2 reconstruction An example of L1&L2 reconstruction of a simulated 1 TeV muon event in CSCsof a simulated 1 TeV muon event in CSCs
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Drawn by Ivan Belotelov, JINR
generated muon
* CLCTs
L1 reconstruction
L2 reconstruction
CSC hits
CSC track segments
CSC hits used for L2 reco
++ Kalman filter propagation states
Modified object-oriented reconstruction
Pt(gen)=1000 GeV
Pt(L1)= 6 GeV
Pt(L2)= 1300 GeV
rad
cm
Z, cm
Z, cm
z - projection
z - projection
Reconstructed Pt (L2) distribution Reconstructed Pt (L2) distribution for 1 TeV muons for 1 TeV muons
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
Modified object-oriented reconstruction
The results obtained in cooperation with Ivan Belotelov
Pt, GeV Pt, GeV
ppTT of reconstructed muons in CMS tracking systemof reconstructed muons in CMS tracking system
barrel and endcaps || 2.1 dPt/Pt distributions
Z (1200)
Z (500)
red lines are muon pT distributions generated by PYTHIA
blue lines are reconstructed ones
fitted by Gauss
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
ZZ mass reconstruction mass reconstruction in CMS in CMS
Invariant mass of muon pairs from Pythia
Full reconstruction of invariant mass
Z (500)
Z (1200)
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003
SummarySummaryA transverse momentum of TeV muons at A transverse momentum of TeV muons at L2 trigger level is significantly L2 trigger level is significantly underestimated due to a hard underestimated due to a hard contamination of muon measurements by a contamination of muon measurements by a secondary electromagnetic accompaniment. secondary electromagnetic accompaniment.
Tuned track segment building and new L2 Tuned track segment building and new L2 trajectory seeding algorithm on a base of trajectory seeding algorithm on a base of the best track-segments has been proposed. the best track-segments has been proposed. It essentially improves L2 Pt reconstruction It essentially improves L2 Pt reconstruction in muon system for TeV muons.in muon system for TeV muons.
Mass resolution of 5-6% for new gauge Mass resolution of 5-6% for new gauge boson resonances Zboson resonances Z (500) and Z (500) and Z (1200) in (1200) in CMS has been obtained (with a natural CMS has been obtained (with a natural width of 2-3width of 2-3%).%).
V. Palichik NEC’2003 Varna, Bulgaria 15 September, 2003