FOPITOF Upgrade - PowerPoint PPT Presentation

Title: FOPITOF Upgrade


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FOPI-TOF Upgrade

• A.Schüttauf GSI

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Outline

• FOPIs TOF Upgrade
• RPC-Hardware
• RPC-Electronic
• RPC-Interface
• Test beam results
• Summary Outlook

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FOPI TOF-Upgrade
Physics case K- flow to determine in-medium
potential Needs improved TOF in the lt 100 ps for
kaon identifica-tion up to 1 GeV/c
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Why RPCs ?
For high granularities experiments price is an
issue. FOPI TOF Size 5 m2 Channels
5000 ?tlt100 ps ??lt0.5 cm
Central Au-Au collision at 1.45 AGeV has
60- particles in the acceptance of the proposed
RPC barrel This needs a granularity of 700 cells
(2500 strips)
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Strip Anode RPCs
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TOF Detector Layout
1 Super module (SM) 5 RPCs 16 strips/RPC
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Double hit capability
During the test beam in May 2002 we encountered
a problem with enhanced hit multiplicities in
the RPC. This could later be attributed to
internal reflections inside the counter.
Solution Adapt your counter to 50 1 ?
We went thru a painful review of our counter
impedance.
K.Hildenbrand, V. Simion
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Electronic Design
Old
TAC
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Electronic Resolution
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RPC-Electronic Interface
Flexible kapton cable 3 layer design in 250
?m 16 strips with 50 ? lines
M. Ciobanu, S. Häussler
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Test Setup Oct. 2003
Beam Protons at 1.0 2.0 AGeV Rate 20-80
Hz/cm2 Gas C2F4H2/isobutane/SF6 85/5/10
Setup
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Reflections
Counter reflections are below 1 Reflection at
the Lemo? MEC1 adapter will disappear with new
interface.
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Voltage Scan 90 cm RPC
Slewing correction
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Voltage Scan 20 cm RPC
Strips wise
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Summary Outlook

• Reflections solved ! r lt 1
• Intrinsic electronic resolution ?I lt 30 ps
• Clock distribution is working !! ?CS lt 15 ps
• Time resolution per module DaL 11a (14) ?t lt 80
  ps DaS 6a (12) ?tlt 70 ps
• Efficiency per module DaL 11a (14) eff.
  95 DaS 6a (12) eff. 99
• Flex. cable possible for timing.

• Double hit resolution !!!
• Two counter matching.
• Flex cable anode sandwich.
• 90 cm 6 gaps 50 ?.
• Fishing rod ? glass fiber ?
• From 1.1 mm ? 0.5 mm glass.
• From 300 ?250 ?m gap.

GSI-Future Compressed Bayonic Matter
(CBM) European JRA FEE-ASIC Readout (TAC)
Highly segmented anode structures.
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People
GSI-KPI M.Ciobanu K.Hildenbrand
M.Marquardt A.Schüttauf V.Simion A.Weinert Forme
r C.Finck A.Gobbi GSI-ELEX E.Badura H.Hardel K.K
och R.Schulze
HD-University E.Cordier N.Herrmann
IPNE, Bucharest M.Petrovici
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Reflections I
May-June 2002 Test Beam
N.Herrmann
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Reflections II
Talk
?-Setup Coincidence of plastic and RPC
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Double hit capability
Solution Adapt your counter to 50 1 ?
K.Hildenbrand, V. Simion
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Dark rate

• Takes 3 day under high voltage.
• Does not scale with border length
• but with the area.
• Low value 1 Hz/cm2.

90 cm counter
20 cm counter
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TAC Principal
TALK
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OLD Tac-Quilo-Quisa
C.Finck, A.Gobbi
TALK
GSI-ELEX R.Schulze,H.Hardel K.Koch,E.Badura
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Cluster Timing
TALK
DaS 6a 12 strips 6 gaps 9.6 kV
Time resolution per strip
Cluster parameters
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Slewing Correction
Uncorrected TOF spectra for all strips.
Determined walk correction Twalk 100 ps
Corrected and normalized TOF
TALK
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Setup Oct. 2003
Trigger ? PM1 PM2 Efficiency ? PM1 PM2
PM3
Talk