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News/”highlights” dalla CMSweek. ( con qualche dettaglio su analisi dei CRAFT data ). U.Gasparini. LHC & CMS. LHC, Evans. “CRAFT”. CMS, Verdee. “on track”, ma con molte cose da fare…. CMS(II). Detectors & Physics. CRAFT. Data vs MC…. Pre-selection: at least 2 “good” DT segments - PowerPoint PPT Presentation
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15 December 2008 Pd meeting 1
News/”highlights” dalla CMSweek
( con qualche dettaglio su analisi dei CRAFT data )
U.Gasparini
15 December 2008 Pd meeting 2
LHC & CMSLHC, Evans
CMS, Verdee
“on track”,ma con molte cose da fare…
“CRAFT”
15 December 2008 Pd meeting 6
Data vs MC…
All plotsnormalized toNr. of events passingpre-selection
Pre-selection:at least 2 “good” DT segmentsboth in upper &lower sectors
~4.1%of events withless than 2 STA mu(3.7% in MC)
15 December 2008 Pd meeting 7
Tracker Efficiency StudiesTracker Efficiency Studies
Efficiency is around 90%not yet the optimal value compared to pp (simulation)
1) Eff. vs pt of the STA muons
(|d0| < 50 cm and |dz| < 50 cm)
2) Eff. vs d0 for STA muons
(pt > 12 GeV and |dz| < 50 cm)
J.Andrea/ULPCombinedTrack Finder
Road Search
CosmicTrack Finder
to beunderstood…
15 December 2008 Pd meeting 9
we could expect resolutions: cosmic global > 1-leg > 2-leg > lhcSTA*
CosmicMCBon10GeV GEN-SIM-RAW sample, reconstruction in 2_1_12
Pt resolution defined as:(1/pT
reco-1/pTsim)/(1/pT
sim) comparing the innermost state and its closet primary muon simhit
Pt resolution: MC expectationsPt resolution: MC expectations
15 December 2008 Pd meeting 10
Momentum scale: 1-leg STA vs Tracker trackMomentum scale: 1-leg STA vs Tracker track
[1/pt(1legSTA) -1/pT(Tracker) ] / (1/pt(Tk)
~ 0
~ -12%
-0.5 0.5 0.5-0.5
Underinvestigation…requiresdetailedstudies(B fieldeffects?see nextslides)
=22.2%=22.7 %
resolutionsas expected
-0.5 0.5 0.5-0.5
15 December 2008 Pd meeting 11
upperupper STA-leg vs Tracker track STA-leg vs Tracker track
STA upper leg
Trackertrack
[1/pt(1legSTA) -1/pT(Tk) ] / (1/pt(Tk)
~ -20% ~ -2%
15 December 2008 Pd meeting 12
lowerlower STA-leg vs Tracker track STA-leg vs Tracker track
STA lower leg
Trackertrack
15 December 2008 Pd meeting 13
Momentum scale: back to DT segmentsMomentum scale: back to DT segments
Bending angledifference betweensegments inconsecutive stations
B field in theoutermost parts ofIron Yokesseems to belower (~30%effect)than the current mapping value
mean = -15.7± 0.1 mrad mean = -21.6±
0.1 mrad
mean = -19.0± 0.1 mrad
mean = -13.5± 0.1 mrad
mean = -14.2± 0.1 mrad
mean = -13.4± 0.1 mrad
B= 3.8 T
15 December 2008 Pd meeting 14
Momentum scale (II)Momentum scale (II)
Width ofdistributioncompatible with mult.scattering as observed in B=0 data
B= 0 B= 3.8 T
=5.7 mrad =5.4 mrad
mean=-8.9± 0.1 mrad
mean=-8.2± 0.1 mrad
mean=-11.7± 0.1 mrad
mean=-12.5± 0.1 mrad
mean= 0.3 ± 0.1 mrad
mean= 0.4 ± 0.1 mrad
mean= -0.9 ± 0.1 mrad
misalignm.effects < 1 mrad
mean=-8.6± 0.1 mrad
mean=-7.6± 0.1 mrad
15 December 2008 Pd meeting 15
Energy LossEnergy Loss N.Kypreos/UFL
Some features in the distributions, some of them understood other need to be studied
15 December 2008 Pd meeting 16
• dE (inner E – outer E) vs. dx Distance (inner, outer)– MC/Data shape agree very well– Clear dependence on the path of
track– Steps on the curve are because
energy loss is less in muon chamber than in iron
• dE/dx as a function of energy @ innermost– Similar curve as HCAL energy-loss vs.
muon energy (by Jordan D. & Efe Y.)– Material is more complicated
• Whole detector: air, iron, calorimeters, tracker & muon chambers…
– MC/Data agrees well at low-energy region
Energy Loss (II)Energy Loss (II)
C.Liu/Purdue
15 December 2008 Pd meeting 17
YB+2 SA 2 legs @ IPNominalCRAFT_All_V3
Z @ IPZ @ IP Phi @ IPPhi @ IP
Pt(upper)- Pt (down) / Pt (down) Pt(upper)- Pt (down) / Pt (down)
Theta @ IPTheta @ IP
From 2.3 mm From 1.2 mrad up to 0.6 mrad
From 2 mradup to 0.9 mrad
up to 1.6 mm
Alignment effectsAlignment effectsInclusion of muon alignment data slightly improve STA reconstruction:
A.Calderon
15 December 2008 Pd meeting 18
3.8 T
CMSSW map (B(solenoid)=3.8): 1.640 T 1.620 T 1.740 T
IEEE-NSS-2008_PID771926
15 December 2008 Pd meeting 19
Bfield from data
1
2
r sin 1
r sin 2
= r (sin2 – sin1)
B = pT/ (0.003 r)
from tracker + energy loss
= 29 cm
=62 cm
= 62 cm
r
15 December 2008 Pd meeting 20
B field from data…B field from data…
??
CMSSW map (B(solenoid)=3.8): 1.640 T 1.620 T 1.740 T
B=1.44±.01
B=1.85±.01
B=1.48±.01
B=0.97±.02
B=1.96±.03
B=1.02±.02
issuemu+ vs mu-to be undesrtood…