D0 K, simulation

1
D0 ?K-,? simulation
I.Vassiliev (GSI) CBM collaboration meeting
09-Mar-05

• Simulation tools (cbmroot v04) geometries
• Signal and Background simulation
• Tracking Vertexing in the Magnetic Field
• Variables and cuts. Cuts optimisation
• Comparison of MAPS and HYBRID detectors
• Trigger feasibility study
• Outline

2
Simulation tools (cbmroot v04) geometries

• CBM framework version 04
• 3 first Sts in the vacuum
• "MAPS" (100 ?m) and "HYBRID" (700 ?m thickness)
  first two station geometries with various pixels
  size (35x35, 350x50 ?m)
• 7 stations at 5, 10, 20, 40, 60, 80, 100 cm
• stations 37 200 ?m (strip like)
• single Au target 250 ?m,
• GEANT3, UrQmd (central at 25 GeV) and D0 ?K-,?
  (V.Friese) generators
• Tracking and vertexing (I.Kisel S.Gorbunov) in
  the Magnetic Field

3
Signal and Background simulation

• Signal 105 events D0 ?K-,?

4
Signal and Background simulation

• Background 104 UrQmd events

5
Tracking Vertexing

• by I.Kisel S.Gorbunov
• ReadEvent()
• //Geometries, materials, etc.
• Sts(MAPS,Hybrid, Strip) HitsProducer()
• FitMC()
• IdealTrackFinder
• PrimaryVertexFinder
• FitPerformance()
• UserEventAnalysis()

6
Tracking Vertexing

• ReadEvent()
• Geometries, materials, etc.
• Sts(MAPS,Hybrid, Strip) HitsProducer()
• FitMC()
• IdealTrackFinder
• PrimaryVertexFinder
• FitPerformance()
• UserEventAnalysis()

7
Tracking Vertexing

• ReadEvent()
• Geometries,
• materials, etc.
• Sts(MAPS,Hybrid,
• Strip) HitsProducer()
• FitMC()
• IdealTrackFinder
• PrimaryVertexFinder
• FitPerformance()
• UserEventAnalysis()

c? 123 µm
8
Tracking Vertexing

• Event Analysis
• Event Topology (MC), Event Reconstruction
• (Primary tracks vertex, search K0S ? ?- ?-
  D0)

9
Tracking Vertexing

• Event Analysis
• Event Topology (MC), Event Reconstruction
• (Primary tracks vertex, search K0S ? ? - ?
  - D0)

10
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m)
• Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

11
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m)
• Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

12
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m)
• Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

13
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m) Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

14
Trigger feasibility study
103 events mix events UrqmdD0 ?K-,?

• No Particle ID
• realistic tracking
• and vertexing
• 400 (1000) reduction factor
• 1.510-4 D0 per event with
• BR3.65
• 900 charged hadrons per event

15
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m)
• Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

16
Variables and cuts. Cuts optimisation

• Impact Parameter cut
• (70 ?m lt IP lt 500 ?m)
• Z-vertex for D0 ?K-,?
• (Z2 gt 250 ?m)
• P D0 pointing to the
• Primary Vertex (30 ?m)
• Pt K-,? gt 0.5 (0.45) GeV
• P K-,? gt1.5 GeV
• ?2 lt 5 for the
• Secondary vertex

17
Trigger feasibility study
103 events mix events UrqmdD0 ?K-,?

• No Particle ID
• realistic tracking
• and vertexing
• 400 (1000) reduction factor
• 1.510-4 D0 per event with
• BR3.65
• 900 charged hadrons per event

18
Trigger feasibility study
19
Outline

• Track fitting in the Magnetic Field is
  available
• Various Sts detector configurations have been
  studied
• MC simulation shows feasibility to measure D0
  ?K- ?
• Developed cuts allows to create the L1 Trigger
  model with RF 1000
• Hybrid pixel size is critical for the D0
  detection
• Next steps
• Track finding
• D MC simulation