pid band structure check and p p pi- final state
DESCRIPTION
PID Band Structure Check and p p pi- final state. Y.C.Han@ K0 meeting Nov22, 2007. PID Band Structure. Yellow: Deutron Red: Proton Purple: Kaon Green: Pi+ Blue: Pi-. Time Relation. IH CTime. OH MeanCTime. Flight Time (OH – IH). Target Region. -2.5cmTRANSCRIPT
PID Band Structure Checkand
p p pi- final stateY.C.Han@
K0 meeting Nov22, 2007
PID Band Structure
Yellow: Deutron
Red: Proton
Purple: Kaon
Green: Pi+
Blue: Pi-
Time RelationIH CTime
OH MeanCTime
Flight Time
(OH – IH)
Target Region
-2.5cm<X<1.5cm
Particle Type
Pion MinusPion Plus
ProtonUnknown
Vertex Type
Proton Pi+ Pi-Proton Proton Pi-
Pi+ Pi- Pi-Pi+ Pi+ Pi-
Unknown
IH OH and Tag segment
No obvious dependence on single segment.
Conclusion
PID band structure related to the 2nsec like band structure of time of flight;
The band structure tends to more obvious in the non-target region, unknown particles, unknown vertex; while shows no dependence on the IH, OH, or Tag segment hit.
Tagger photon and pppi final state
Final Momentum= | mom_p1+mom_p2+mom_pi- |
Cut region
50
40
30
20
10
1
Cut ResultJan2007 Total pppi- Events: 22138
50
2470 events
40
1953 events
20
999 events
30
1454 events
10
508 events
1
58 events
IH deposit energy correctionMean Momentum
Proton
520
531
Pi-
363.5
365.9
After correction
After correction
50
40
30
20
10
1 /c
After correction
2431 events 1935 events
1455 events 947 events
457 events 51 events
5040
20
1
30
10
Cut region
MeV/c
Cut region
MeV/c
Tagger photon vs final mom with final IM cut
Cut Region
50
40
30
20
10
1 /(c*c)
Tagger photon vs final mom with final IM cut
2482 events
1465 events
469 events
2014 events
947 events
45 events