- BEMC
- EEMC
- ETOF
- FCS
- FGT
- FGT. . . . . . . . . . I N S T R U C T I O N S
- FGT. . . . . . . . . . P H Y S I C S
- FGT. . . . . . . . . . S I M U L A T I O N S
- FGT. . . . . . . . . H A R D W A R E -- D E T E C T O R
- FGT . . . . . . . . . . A N A L Y S I S
- Estimation of error of A_L including detector response, May 2008 (Jan)
- study 1 of S/B, A_L, LT=800/pb (Jan)
- study 2 , err(AL) , eta=[1,2], LT=800/pb (Jan)
- study 3 , cross check w/ FGT proposal, LT=800/pb (Jan)
- study 4 , LT=300/pb, eta=+/-[1,2] , W+/- (Jan)
- study 5 charge sign discrimination
- study 6 final plots for PAC, May 2008
- study 7 revised for White Paper, AL(eta), AL(ET) , (Jan)
- study 8 no QCD backg AL(eta), AL(ET), also rapidity (Jan)
- study 9 sensitivity of STAR at forward & mid rapidity
- study 9a sensitivity mid rapidity LT=10/pb
- study 9b sensitivity at mid rapidity LT=10/pb Pol=50% or 60%
- e/h algo for Barrel
- e/h discrimination in the Endcap
- Estimation of error of A_L including detector response, May 2008 (Jan)
- FGT . . . . . . . . . . C A L I B R A T I O N
- FGT . . . . . . . . . . D O C U M E N T S
- FGT . . . . . . . . . . DAQ
- FGT . . . . . . . . . . M E E T I N G S
- FGT. . . . . . . . . . H A R D W A R E -- E L E C T R O N I C S
- FGT. . . . . . . . . . H A R D W A R E -- S L O W C O N T R O L S
- FGT. . . . . . . . . . P H O T O - - G A L L E R Y
- FGT. . . . . . . . . . S O F T W A R E
- FGT. . . . . . . . . . V A R I A
- FGT. . . . . . . . . . x -T R A S H (node for recycling)
- FPD & FMS & FPS
- FTPC
- FTT
- HLT
- L3
- PMD
- PP2PP
- RICH
- Roman Pot Phase II*
- SSD
- SVT
- Slow Controls
- TPC
- TRG
- Trigger Detectors
- VPD
- test
study 2 , err(AL) , eta=[1,2], LT=800/pb (Jan)
Updated on Tue, 2008-05-13 11:45. Originally created by balewski on 2008-04-29 08:10.
Under:
A_L on this has a WRONG sign, I did not know RHICBOS is using different sign convention, JAN
Section A) Theoretical calculations:
Assumed LT=800/pb
fpol=new TFile("rb800.w+pola_grsv00_2.root"); <--GRSV-VAL (maximal W polarization)
funp=new TFile("rb800.w+unp_ct5m.root");
histo 215
Total W+ yield for lepton ET[20,45] GeV and eta [1,2] is of 7101 for unpolarized cross section and of -2556 for the helicity dependent part.
Assuming 70% beam polarization measured spin dependent asymmetry:
eps_L= P* del/sum= -0.25 +/-0.012
(assuming err(eps)=1/sqrt(sum) )
Fig 1 , W+ : top row - unpol & pol cross section GRSV-VAL (maximal W polarization),
bottom left: integrated over eta, black=unpol, red=pol
bottom right: asy=P *pol/unpol vs. lepton PT, green=fit
Total W- yield for lepton ET[20,45] GeV and eta [1,2] is of 5574 for unpolarized cross section and of +2588 for the helicity dependent part.
fpol=new TFile("rb800.w-pola_grsv00_2.root");
funp=new TFile("rb800.w-unp_ct5m.root");
histo 215
Assuming 70% beam polarization measured spin dependent asymmetry:
eps_L= P* del/sum= +0.325 +/-0.013
Fig 2. W- GRSV-VAL (maximal W polarization)
Section B) Folding in e+,e- reconstruction and QCD background
Assumptions:
- LT=800/pb
- beam pol P=0.7
- e+,e- reco efficiency is 70%, no PT dependence
- QCD background to W contamination, after e/h algo no spin dependece
lepton PT range | w=backg/signal |
20-25 GeV | 5.0 +/- 10% |
25-30 GeV | 1.0 +/- 10% |
30-35 GeV | 0.8 +/- 10% |
35-40 GeV | 0.7 +/- 10% |
40-45 GeV | 0.6 +/- 10% |
Formulas:
- Theory yields : unpol=sig0(PT) & pol=del(pt) , S1=(sig0+del)/2, S2=(sig0-del)/2
- Measured yields N1, N2 , for 2 helicity states
- N1(PT)= eff*[ sig0+del + sig0 * w) /2
- N2(PT)= eff*[ sig0-del + sig0 * w) /2
- ALraw(PT)= P* (N1-N2)/ (N1+N2)
- V(ALraw(PT))= 1/(N1+N2) <-- variance
- ALsig(PT)= (1+w(PT))* ALraw(PT)
- V(ALsig)= (1+w)2*V(ALraw ) + V(w)*(ALraw)2
- dil=1+w
- QA= |(ALsig)/err(ALsig)| - must be above 3 for meaningful result
Fig 3, Results for W + GRSV-VAL (maximal W polarization)
Left : N1(PT)=red, N2(PT) blue. Right: reconstructed signal AL
ipt=0 y-bins=[41,50] unpol=1826.5 pol=-327.3 AL=-0.125 +/- 0.0234 QA=1.8 B2S=5.0 , N1=3721 N2=3950 ALraw=-0.021 +/- 0.011, dil=6.00 ALsig=-0.125 +/- 0.069 ipt=1 y-bins=[51,60] unpol=1403.0 pol=-265.8 AL=-0.133 +/- 0.0267 QA=2.9 B2S=1.0 , N1=889 N2=1075 ALraw=-0.066 +/- 0.023, dil=2.00 ALsig=-0.133 +/- 0.046 ipt=2 y-bins=[61,70] unpol=1233.7 pol=-384.7 AL=-0.218 +/- 0.0285 QA=4.7 B2S=0.8 , N1=643 N2=912 ALraw=-0.121 +/- 0.025, dil=1.80 ALsig=-0.218 +/- 0.047 ipt=3 y-bins=[71,80] unpol=1811.9 pol=-1041.9 AL=-0.403 +/- 0.0235 QA=10.0 B2S=0.7 , N1=713 N2=1443 ALraw=-0.237 +/- 0.022, dil=1.70 ALsig=-0.403 +/- 0.040 ipt=4 y-bins=[81,90] unpol=808.8 pol=-525.2 AL=-0.455 +/- 0.0352 QA=8.1 B2S=0.6 , N1=269 N2=637 ALraw=-0.284 +/- 0.033, dil=1.60 ALsig=-0.455 +/- 0.056 sum2=7084.000000 sum3=-2544.850098 asy=-0.251
Fig 4, Results for W - GRSV-VAL (maximal W polarization)
ipt=0 y-bins=[41,50] unpol=1239.1 pol=490.8 AL=0.277 +/- 0.0284 QA=3.2 B2S=5.0 , N1=2774 N2=2430 ALraw=0.046 +/- 0.014, dil=6.00 ALsig=0.277 +/- 0.086 ipt=1 y-bins=[51,60] unpol=1452.7 pol=641.2 AL=0.309 +/- 0.0262 QA=6.6 B2S=1.0 , N1=1241 N2=792 ALraw=0.154 +/- 0.022, dil=2.00 ALsig=0.309 +/- 0.047 ipt=2 y-bins=[61,70] unpol=1426.5 pol=689.9 AL=0.339 +/- 0.0265 QA=7.5 B2S=0.8 , N1=1140 N2=657 ALraw=0.188 +/- 0.024, dil=1.80 ALsig=0.339 +/- 0.045 ipt=3 y-bins=[71,80] unpol=1135.3 pol=596.1 AL=0.368 +/- 0.0297 QA=7.6 B2S=0.7 , N1=884 N2=467 ALraw=0.216 +/- 0.027, dil=1.70 ALsig=0.368 +/- 0.049 ipt=4 y-bins=[81,90] unpol=313.8 pol=166.4 AL=0.371 +/- 0.0565 QA=4.3 B2S=0.6 , N1=234 N2=117 ALraw=0.232 +/- 0.053, dil=1.60 ALsig=0.371 +/- 0.086 sum2=5567.280273 sum3=2584.398926 asy=0.325
Another set of results for W+, W- with 2 x worse B/S (the same PT dependence).
Fig 5. W+ GRSV-VAL (maximal W polarization)
Fig 6. W- GRSV-VAL (maximal W polarization)
»
- Printer-friendly version
- Login or register to post comments