06.10.2004 CBM Collaboration Meeting 1

Simulation StatusSimulation Status

V. Friese

06.10.2004 CBM Collaboration Meeting 2

Simulation levelsSimulation levels

Level 1: No magnetic field, ideal tracking (straight tracks)Ideal event vertexIdeal / no PIDUse MC points / tracks (artificial smearing)

Level 2: Simplified detector responseTrack finding and fitting in magnetic fieldPID (TOF/RICH/TRD/ECAL)Single events

Level 3:Detailed detector responseEvent pile-up (MAPS)Delta electron backgroundTiming / Trigger

06.10.2004 CBM Collaboration Meeting 3

Simulation statusSimulation status

Variable Open charm J/Ψ vector mesons hyperons fluctuations

Level 1D0 done, other

channels startedok started

Λ done, multistrange

startedstarted

Level 2 First steps Λ started

Level 3

06.10.2004 CBM Collaboration Meeting 4

Open charmeOpen charme

Level 1 analysis: σvz = 20 μmReconstructed tracks: σvz = 60 μm

No magnetic field applied yet!

06.10.2004 CBM Collaboration Meeting 5

CharmoniumCharmonium

Dielectron channel:Background from „superevent“Reproduces phase space but

neglects correlations

Dimuon channel:Work startedNo absorberDetection of pion decay by kink?

06.10.2004 CBM Collaboration Meeting 6

Low mass vector mesonsLow mass vector mesons

Improved cut strategy

No field yet!

Detailed tracking, pion suppression crucial!

Physics input: use HSD?

06.10.2004 CBM Collaboration Meeting 7

HyperonsHyperons

Work started at PNPI and JINR

Ideal tracking + PID

Track fitting, with field, (ideal track finder)

06.10.2004 CBM Collaboration Meeting 8

FluctuationsFluctuations

First studies done

Problem: Input of physical signal

Other variables ?

<pt>, multiplicity, charge

06.10.2004 CBM Collaboration Meeting 9

TrackingTracking

Various approaches (JINR), only STS, very idealised conditionsTrack finding and track fitting are separated

Track finding

Cellular automaton (no field yet!)Conformal mapping

Track followingHough transform

Track fitting

Different approaches using eq. of motion

We need:take into account STS layout (strips!)take into account MAPS pileuptake into account detector noise and delta electronsdevelop global tracking

06.10.2004 CBM Collaboration Meeting 10

Delta electrons from targetDelta electrons from target

Simulation of delta electrons now stableHit rate in first STS comparable or even larger than from produced particlesVery sensitive to magnetic field -> magnet design

06.10.2004 CBM Collaboration Meeting 11

SoftwareSoftware

Release (production) delayed by 2 months:

Reduce data size

Constant debugging during summer (geometry)

Transport part of software ok now

Production can start

Feasible for report: 100 kEvents central, 25 AGeV

300 kEvents min bias, 25 AGeV

within 10 – 20 days

06.10.2004 CBM Collaboration Meeting 12

SoftwareSoftware

Proposal: Installation of CBM software group

Framework Bertini, Al-TuranyDetector One person from each detector groupPhysics One person from each physics groupTrigger/DAQ

Responsibility for code maintenance, regular meetings

06.10.2004 CBM Collaboration Meeting 13

Input for simulationsInput for simulations

Detector design:

STS Not much progress since LoI! Desperately need strip layout, hit definition

RICH Large progress, design, optical properties, ring recognition. Need: realistic SRS/TRD tracking for ring guidance

TRD first-guess design, hits implementedneed: parametrised response (TR) for PID

TOF first guess design, hits implemented

ECAL: progressed design studies, standaloneneed implementation into framework

06.10.2004 CBM Collaboration Meeting 14

Detector design Detector design ↔ Feasibiliy studies↔ Feasibiliy studies

We still have essentially the CDR detector concept!

Detector optimisation w.r.t. physics observables lacking!

Simulations have to give feedback to detector groups, consider the specific running conditions

(triggered/untriggered)

Connections / communications must be improved