Detector Design

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Coordinate Detector Design

CDet is comprised of many fiber optic cable bundles, scintillation paddles, NINO cards and PMT's. The designs for CDET before construction can be found on the Coordinate Detector page.

Module Composition

 -6 Modules
 -2352 Scintillation paddles
 -168 Fiber optic cable bundles (of 16)
 -168 NINO cards
 -168 PMT's
 -168 High Voltage Channels

CDet is composed of 6 modules, each containing 392 scintillation paddles. In each paddle, a green fiber optic cable threaded through the center to carry the scintillation light to the front of a PMT pixel.

Groups of 14 paddles are connected to a single PMT, which is connected to a single High Voltage supply.

Each PMT is connected to a NINO discriminator card. The ADC signal is then sent through delay cables into the Fastbus DAQ unit, at the same time the TDC signal is sent directly to the Fastbus DAQ.

PMT Selection

Before the construction of CDet, it was required to have 168 PMT's on uniform pixel output. These PMT's were from a decommissioned FermiLabs detector (which had 180 type 1 PMT's and 317 type 2 PMT's) To do this testing was done on signal outputs given a constant voltage and light source.

A PMT Testing procedure schematic
PMT Testing procedure schematic

The PMT's were then sorted based on performance, and Type 1 PMT's were chosen for CDet. This experiment and File:PMTAnalysis.pdf is the basis for the PMT selection for the modules

Module Mapping







This section is documentation, showing where each component (NINO, Scintillation bar, PMT, etc) is located in each module. A Note about PMT pixels: Each PMT has 16 usable pixels, CDet requires 14. In the previous analysis, the two least uniform pixels were removed from consideration, and of course was required to be logged for DAQ purposes.

NINO Threshold Testing

As of July 2017, the current NINO card threshold settings is 1.5V. This should be updated and checked periodically for each module when testing