A RIKEN BNL Research Center Workshop

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A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
AGS CNI polarimeter. Current Status.
Elastic scattering of polarized beam protons on a
extremely thin carbon target with a small (0.01
(GeV/c)2) momentum transfer. Large cross-section
and a few percent analyzing power.
Igor Alekseev (ITEP)
BNL-2002
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A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
AGS setup
RSC Meeting
24mm
Silicon strip detectors
25cm
10mm
p
A carbon ribbon target 300-600 ?m x 5 ?g/cm2
PC
Si STRIP
12 ns SHAPER
WFD
PREAMP
Transformer
In AGS tunnel
In the HITL2 house
Igor Alekseev (ITEP)
BNL-2002
3
A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
WFD Block Diagram
RSC Meeting
CH1
BUFF
Virtex FPGA
Virtex FPGA
Virtex FPGA
CAMAC Databus
DRAM CNTR
Control CPLD
CH2
DRAM 16 MB
CH3
CH4
140 MHz
420 MS/s/ch 2.4 ns/S
Igor Alekseev (ITEP)
BNL-2002
4
A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
FPGA Block Diagram
RSC Meeting
MUX
ADC
Virtex FPGA
Waveform FIFO / Delay
Mean Subtraction
140 MHz
1/4
Amplitude
Mean Calculation
Time (CFD)
Integral
Control Logic
Result FIFO
Level Trigger
CAMAC readout
x2
70 MHz
Int/Ampl LUT
Time/Ampl LUT
Bunch and Pattern
Bunch 0
AND
GCC
SYNC and Window Logic
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Scalers and histograms
Bunch Distr
Energy P0 Distr
Special Scalers P,P,P0, BG always accessible
INH
Energy P Distr
Energy P Distr
Igor Alekseev (ITEP)
BNL-2002
5
A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
WFD features (V8)
RSC Meeting

• 8-bit amplitude and integral
• 1.2 ns time resolution
• Bunch information
• Windowed sensitivity with 2.4 ns precision
• Digital filter
• Time/amplitude and integral/amplitude LUTs
• LUTs programmable trough CAMAC
• Bunch pattern memory
• 5 always accessible scalers (P,P,P0, 2BG)
• 120 ch bunch distribution
• 3128 ch amplitude distributions for P,P,P0
• 3232 or 1664 amplitude versus time histogram
• Crate or front panel INHIBIT stops event
  recognition
• 16 MB of onboard SDRAM 2.5106 events
• Special input for Gauss Clock Counts
• Zero deadtime
• Flexible FPGA configuration

Igor Alekseev (ITEP)
BNL-2002
6
A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
Expected performance
RSC Meeting

• Ramp measurement 2.4 24.5 GeV/c ? a challenge
  for timing.
• Event rate compare to RHIC
• CAMAC readout 106 events / 3s one spill.
• 5108 events per ramp measurement 500 spills
  106 events 40 min.
• Radiation damage to silicon. The whole RHIC
  statistics 20 ramp measurements one day !
• Event rate per strip 0.1 event per bunch
  crossing.

Igor Alekseev (ITEP)
BNL-2002
7
A RIKEN BNL Research Center Workshop A RIKEN BNL
Research Center Workshop A RIKEN BNL Research
Center Workshop
Current status
RSC Meeting

• DONE
• Silicon detectors, preamplifiers and BIAS power
  supplies are installed in the ring and tested.
• Insulation transformers and shaping
  preamplifiers are installed in HITL2 and tested.
• A new 2.5 GHz PC, CAMAC and 6 WFD modules
  installed in HITL2 and tested.
• LeCroy 2367 universal module programmed to
  produce all necessary spill timing signals and
  prescale GCC.
• TO BE DONE
• Get proper signals from AGS.
• Get, install and test frequency multiplier.
• Write DAQ and analysis software.

Igor Alekseev (ITEP)
BNL-2002