MIPP Cerenkov detector HV/LV/crate needs

Status

• Anything upstream of the ADC/TDC.

High Voltage

• Need +2200 Volts @20mA x2 (top/bottom)
• Lecroy 1440 - 20 channels of HV (each 2.5mA) = 2 modules
• Possible to locate in TPC rack?
• Remotely controlled via serial line
• Picture of 1 of the patch panels. Will need to interface with this (1 HV channel for top and bottom of CKov) Or is it easier (from safety regs) to stay with 20-32 separate channels of HV so that there is less power available to each base. Would need to redesign patch panels.

Low Voltage

• Need -5.2 Volts 7.2A x2 (top/bottom)
• "Power-one" 5V/12A supplies readily available.

Threshold

• Need adjustable 0 to -20 Volts (x2?) - low current
• Bases run at low gain, so no need to tune threshold individually for each PMT.

Analog output

• 96 cables (1 per channel)
• In the past: 150 foot run using RG8 into 1882 fastbus ADC. I should test using RG58. Ribbon too lossy. RG8 attenuation length ~400 feet.
• Proposed ADC: LeCroy 4300 (480pC full scale, 11 bits, 50-500 ns gate, input is 17 pair ribbon). 16 channels each = 6 needed

Digital output

• 96 pairs (1 pair per channel)
• 6x17 twisted-pair cable. Needs to be verified that this is ok for 100 foot run.
• Outputs may need to go into a discriminator (6 x Lecroy 3412 for example)
• Then into TDC: LeCroy 4291 (x3) (minimum 50 nsec width, so the discriminator would be needed)

Summary

• Bases are custom equipment (Nevis)
  • Need to go through electrical safety committee. See FNAL web page.
• Stuff from PREP:
  • 2 LeCroy 1440 modules (16 channel, 2.5kV, 2.5mA per channel)
  • 6 LeCroy 4300 ADCs
  • 6 LeCroy 3412 discriminators
  • 3 LeCroy 4291 TDCs
• Rack space:
  • 1 Camac crate
  • HV modules in TPC HV crate?
  • 2 LV power supply (9in x 5in x 4in each for the Power-one supplies)
  • 1 LV bench supply for the threshold