status of k s e analysis c. gattit. spadaro selection on data selection on mc efficiencies from...
Post on 13-Dec-2015
217 Views
Preview:
TRANSCRIPT
Status of KS e analysis
C. Gatti T. Spadaro
Selection on dataSelection on MC
Efficiencies from data, KL e, KS , , bhabha
Efficiencies from MC, KL e, KS , , bhabha
Efficiencies from MC, KS , single-particle method for 2001
Efficiencies from MC, KS , single-particle method for 2002
Dedicated MC for the signal, on a period-by-period basisEfficiencies from MC, KS e, single-particle method
HONEST time scale: weeksHONEST time scale: weeks
Present status of analysis: Present status of analysis:
×
×
×
Fitting with “old” or “new” MCDifferent shape of the background distributionFit residuals are not flat in the signal region
Fitting with “new” MCDifferent shape of the background distributionFit residuals are not flat in the signal region
What is new in the “new” MC
Many methodological differences between “new” and “old”:
NEW analysis:•KL crash algorithm now applied in the MC exactly as in data•Different treatment of split tracks
NEW MC production:
DC•Wire sags•HW wire efficiency simulated•Different s-t relations
EMC•Muon cluster energy rescaled•Pion nuclear interactions revised•KL nuclear interactions revised
GENERATION: KSe3 now available on a run-by-run basis
OLD MC scratched from tapes, we can study it only using selected evts
Comparing “old” vs “new” MC
Background composition:• “” KS with before the DC• “” KS with bad reconstruction, tracking and/or TCL’s• “” KS with an hard , tails of TCL resolution• KS • KS
• Not KSKL events: , KK with a fake KL crash
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MCChecking shape of Background components identified as e
Emiss cPmiss(MeV)
Comparing “old” vs “new” MC
Background composition: compare #(selected evts)/#(KS 104
KS KS KSKL
OLD e
8.38(5) 3.80(3) 1.01(2) 0.067(4)
NEW e
2.02(3) 10.50(7) 3.83(4) 0.78(1) 0.076(6) 0.076(6) 0.19(7)
OLD e
8.16(5) 3.48(3) 0.94(2) 0.065(4)
NEW e
2.07(3) 9.43(7) 3.22(4) 0.53(2) 0.064(5) 0.068(6) 0.19(7)
Comparing “old” vs “new” MCCore of the tracking resolution, compare KS samples from:
• Home-made production for 25 pb downscaled 100
• The same production reconstructed with the old s-t rel.
Pt(MeV)
Pt(MeV) Pt(MeV)
Pt(MeV)
P(M
eV)
P(M
eV)
Pt(MeV)
of correction (MeV)
0.2
To endcap
To barrel
Comparing “old” vs “new” MCCore of the tracking resolution, check gaussian smearing comparing new MC, new MC smeared, and data
M(MeV)
M(MeV)
Core of M
Comparing “old” vs “new” MCCore of the tracking resolution, check gaussian smearing comparing new MC, new MC smeared, and data
M(MeV)
M(MeV)
Left tail of M: resolution tail + early decays + radiation
Comparing “old” vs “new” MCCore of the tracking resolution, check gaussian smearing comparing new MC, new MC smeared, and data
M(MeV)
M(MeV)
Right tail of M: resolution tails
Comparing data vs “new” MCKLe3 sample used to check the distribution for the signal:
• KS tight selection, 490<M<500 MeV, 100<p*<120 MeV• KS auto-triggering• Separation between KS and KL hemispheres• Estimate KL momentum from KS (different than the KL crash estimate)• Correct position of the KL vertex sampling from the KS lifetime, moves KL cluster positions accordingly • Apply the same cuts used for the KS analysis
Comparing data vs “new” MC
Data: 2.9 MeVMC: 2.8 MeV
(E
mis
sPm
iss)
(M
eV)Check standard
deviation of the EmissPmiss distribution:
Y2001 Y2002
Y2001 Y2002 Y2001 Y2002
Y2001 Y2002
Conclusions
1. Checking selection on NEW MC + track momentum smearing:a) Background component distributionsb) Selection efficiency on the background
2. Understand in depth tail below the signal3. Resolution check MC old vs MC new4. KL crash contribution to the EmissPmiss sample: repeat with the NEW
MC smeared, using a sample with Kcrash + 1 trk (P*p cut)5. We are checking many other variables, able to separate between
background components: vertex quality, PID, Pmiss
top related