Charmonium identification via dimuon decay

1
Charmonium identification via dimuon decay

• Anna Kiseleva
• GSI, Darmstadt, Germany
• PNPI, Gatchina, Russia

2
Outline

• Setup of the simulations
• Study of the background parameters
• Methods of the invariant mass calculation
• Invariant mass spectrum signal background
• Future steps

3
Setup

• All CBM-detectors
• Framework cbmroot
• Magnetic field FIELD.v04_pavel.map
• Background UrQMD (central AuAu collision at 25
  AGeV)
• J/Psi signal Pluto
• 1 momentum resolution for the signal
• 100 efficiency and particle identification

4
Geometry
Cave Magnet Target Pipe STS RICH TRD RPC Gas-detec
tor
5
Momentum distribution for the background
6
Momentum distribution for the signal
Momentum distribution for the signal and
background
7
Other parameters of the background
kink angle
opening angle
8
Methods of invariant mass calculation event by
event
9
Methods of invariant mass calculation superevent
10
Methods of invariant mass calculation superevent
event-by-event
11
Invariant mass spectrum (signal background)
J/?
12
To do

• Simulation with tracking reject muons from ? and
  K decay
• Simulation with muon efficiency of ECAL or muon
  detector
• Use data for another detectors (STS, TRD, ECAL)
• Study of the parameters for the signal/background
  selection

13
Thank you for your attention!
14
Charmonium identification via dimuon decay

• Anna Kiseleva
• GSI, Darmstadt, Germany
• PNPI, Gatchina, Russia

15
?? from ?? and ?? decay into UrQMD events
N/N0 exp(-L/c???)
L 11 m
Pt 1 GeV/c
2 GeV/c
??ct 7.8 m m 139.57 MeV
0.82
0.91
??ct 3.7 m m 493.7 MeV
0.23
0.48