Status of MAPS Geometry Simulation

Yoshinari Mikami

University of Birmingham

21th April 2006

MAPS Meeting at Rutherford Appleton Laboratory

Introduction

We studied Si thickness modification (15mm).

Mokka-05-05 and LCIO-v01-06 is used.

We tried Cell size modification (50mm x 50mm).

Mokka-06-00 and LCIO-v01-07 is used.

Si Thickness Geometry Comparison

Lower PCB

PCB

Si Sensitive

Upper PCB

Upper PCB

Si Non-sensitive

Si Sensitive

Lower PCB

Default

MAPS Si thickness

0.8 mm

0.5 mm

0.8 mm

0.8 mm

0.015 mm

0.485 mm

0.8 mm

Geant4 Adaptive GUI (GAG) output distributions looks fine.

5 mm interval is the same and center values of each layer radius shifted 242.5 mm.-->Agree with expects.

Default thickness

MAPS thickness

Layer #2 Radius [mm]

arbitrary

Layer Interval Distribution

Layer #1 Radius [mm]

20 GeV Single Electron Energy Deposit

#hits mainly depends on radiator tungsten thickness.

MAPS/Default ratio for energy deposit per event = (3.04 +/- 0.10) %

MAPS thickness 15mm

(10,000 events)

GeV

#hits/event = 240.6 +/- 2.4 (stat)

Mean E of hits = 58.7 +/- 0.6 KeV

#hits/event = 346.5 +/- 11.0 (stat)

Mean E of hits = 1.34 +/- 0.04 MeV

MAPS/Default ratio for mean of hits = (4.38 +/- 0.14) %

(-->Agree with thickness 3% reduction.)

Default thickness 500 mm

(1,000 events)

E deposit/event = 464 +/- 15 MeV

E deposit/event = 14.1 +/- 0.2 MeV

GeV

GeV

Crosscheck with 20 GeV Single Muon

#hits/events = 77.8 +/- 1.1

Mean energy of hits = 3.72 +/- 0.05 KeV

Energy deposit/event = 289.8 +/- 4.1 KeV

Si dE/dx | = 3.88 MeV/cm (PDG)

3.88MeV/cm x 40 (layers) x 15 mm = 233 KeV

GeV

MAPS thickness

(5,000 events)

Energy deposit with muon

min

Agree with expect.

(20 GeV is higher velocity

than the velocity of MIP.)

Si Sensitive Thickness Dependence (1)

- 20 GeV single electron 10,000 events

- Cell size is still 1cm times 1cm

#hits/events depends on Si sensitive thickness slightly.

Si Sensitive Thickness Dependence (2)

- 20 GeV single electron 10,000 events

- Cell size is still 1cm times 1cm

Error bar is within square

Mean energy of hits depends on Si sensitive thickness linearly.

Cell Size Modification (50mm x 50mm)

20 GeV electron 5,000 events.

Si sensitive thickness is 15 mm

GeV

#hits/events = 2065.5 +/- 29.2

Mean energy of hits = 7.10 +/- 0.10 KeV

Energy deposit/event = 14.7 +/- 0.2 MeV

Compared with only thickness modification -> 8.6 times #hits/event

-> The same energy deposit.

Data Size/CPU Time Comparison

Default 500 mm thickness and 1cm x 1cm cell size

250Mbytes/1,000 events

154 minutes CPU time/1,000 events

MAPS 15mm thickness and default 1cm x 1cm cell size

79.4Mbytes/1,000 events

157 minutes CPU time/1,000 events

MAPS 15 mm thickness and 50mm x 50mm cell size

111Mbytes/1,000 events

239 minutes CPU time/1,000 events

#hits/events: (15mm x 1cm^2) < (500mm x 1cm^2) < (15mm x 50mm x 50mm)

#Secondary shower/cell: (15mm x 50mm x 50mm) < (15mm x 1cm^2) < (500mm x 1cm^2)

Summary

Thickness modification will be fine.

Cell size modification studies were started.

Next steps

Cell division for 5mm times 5mm to study efficiency (It needs modifying code to assign more bits on #cells.)

Digitization studies to make cross-check

Position/Angle/Energy resolutions

Backgrounds study with physics events

Systematic studies and cross-checks for all steps

Summary and Future Prospects

2006-04-13T09:37:56