AGENDA

1
AGENDA

• Approval of agenda and minutes of last meeting
• Integration. L. Leistam (09.10-09.25)
• FMD design overview. JJG (09.25-09.50)
• Si-FMD Background simul. A. Maievskaia
  (09.50-10.15)
• Si-FMD FE and RO electronics. B.S.Nielsen
  (10.15-10.40)
• Coffee break
• Si Prototype. A. Angelis/NN (11.00-11.25)
• T0 status. V.Grigoriev/ H. Trzaska
  (11.25-11.50)
• V0 status J.Y.Grossiord/L. Montano (11.50-12.15)
• PMD news. Y. Viyogi (?) (12.15-12.30)
• Summary-Conclusions-Actions,
• Formation of TDR writing group. JJGAll
  (12.30-13.00)
• AOB

2
Main issues

• Si-FMD
• Freeze inner radius? Freeze general geometry.
• Integration with ITS and other FD
• Define Services (cables, cooling, etc.)
• Define Responsibilities, timetable
• Go to bids. Commence Prototyping.

• T0
• Define final geometry (L,R)
• Trigger
• Timetable
• Go to prototyping
• V0
• Design status
• Integration, trigger
• Prototyping.
• Organization
• Responsibilities
• TDR writing group formation

3
Overall Geometry

• -5.4lt ? lt-1.6
• 3 lt ? lt 1.6

Si 4
Si3(moved)
Si2
Si1
4
Integration in ALICE
Si-1
V0-R
Si-2
T0-R
Si-3
5
Si1 with 6 Wafers
Si 1 outer
2 Rings
Si 1 inner
6
Si1 with 6 Wafers
Outer Ring
24
R35.1cm
24
16
R22.1cm
R39.9cm
8
R28.8cm
R17.1cm
R5.3cm
2 Rings
Inner Ring
7
Ring geometry
!!30 cm vertex shift ? ?1.2
8
Background and acceptance

• Pseudorapidity coverage
• Si1 Si2 (inner and outer)
• d(IR)62.8 and 75.8 cm
• 1.51 lt?lt 1.94
• 2.03 lt?lt 3.58
• Si3 d(IR)345cm
• -5.28 lt?lt -3.71
• Vertex shift (30cm) d? ? 0.3

9
Background simulationsAlla Maevskaia
10
Background simulationsAlla Maevskaia
11
Background simulationsAlla Maevskaia
12
Background simulationsAlla Maevskaia
13
RHIC vs. LHC
BRAHMS _at_ RHIC 200

• RHIC
• (?s130 AGeV)
• -5 lt?lt 5
• Plateau 2 lt?lt 2
• (40 of range)
• dN/d?(?0)550.
• (?s200 AGeV)
• -6 lt?lt 6 dN/d?(?0)610.
• Nch 5100
• LHC
• (?s5800 AGeV)
• -9 lt?lt 9

BRAHMS 200AGEV
14
Limiting particle prod. in fragmentation region

• RHIC saturation of particle production in
  fragmentation region is already achieved at SPS.
• ?Width of Frag. Region is
• ?? ? 3.
• LHC ? (9,9)
• RHIC200 ? (6,6).
• ? May expect that central region at LHC extends
  to (6,6).
• ? Si-FMD and V0 detectors cover (-1.5,5.3), i.e.
  interesting region.

BRAHMS RHIC 200. Prelim
BRAHMS. Subm. to Phys Lett. B. 2001
15
Si-FMD Role in Trigger

• Physics and rates
• Central PbPb
• Nch(Si) 15.000-20.000
• pp
• Nch(Si) 50-100
• PbPb 8kHz. (1kHz central)
• Average event spacing gt100?s
• pp up to 1 coll/bunch crossing
• Average event spacing 25 ns

• WHO does it?
• LVL0 Timing T0
• Vertex (? 1-2 cm) T0
• Vertex (? 0.1-0.2 cm) TPC
• Rough on-line Centrality cut on dE
  V0
• pp trigger V0
• Timingvertex(pp) T0,V0
• Precise centrality Si
• Fluctuations Si
• Azimuthal distribution Si
• Off-Line PID (dE) Si
• Level 0 T0,V0
• Off-line, Higher level Si

16
Electronics overview

• Assume 128 strips/wafer
• Assume 32 channels/chip
• Assume 8 chips/RO card

17
Cost Estimate

• VERY uncertain and preliminary estimate
• in CHF.
• 6Ø still experimental
• Test production batch 16-25 wafers

18
Si-FMD Timetable

• .

19
Responsibilities Si-FMD

• TASKS
• Update geometry and integration drawings
• Update simulations of background, resolution and
  performance
• Choice of electronics
• Tender and order prototype 6 wafers
• Construct and test FERO system
• Test DAQ and integrate with DAQ
• Update prelim-TDR-started
• PPR- needs to develop

• WHO?
• NBI
• INR
• NBI
• NBI
• NBI ?
• ?
• NBI, INR, Athens, ?

20
Responsibilities T0 V0

• TASK
• T0 Tech. Design study
• T0- technology decision and funding
• T0 prototyping
• V0 TDR
• Prototyping

• Who?
• MEPHI and Jyvaskyla
  
• Lyon and Mexico

21
Endorsed Recommendation to ALICE Forum,TB,MB,CB

• Si-FMD acceptance downscoped to
  -5.28 lt ? lt -3.71
• 1.51 lt ? lt 3.58
• Background from beam pipe important-gt redesign
  needs to be pursued
• Si-FMD not present in trigger at LVL0. Analog
  sum trigger for LVL1 seems possible but not
  likely.
• FEE /(ampl. Chip. Hybrid, ADC, receiver) can be
  developed together with IDEAS-Norway.
• Revisit ? segmentation for flow analysis

• T0 is main Alice timing trigger
• Two arm necessary for good vertex also in absence
  of TPC and pixels
• Radiator-PM is baseline design
• Two-arm V0 for beam gas-rejection
• V0 is main Alice centrality trigger
• Integrate Si3, T0(L), V0(L) and PMD