Photon Counting Experiment

photon_signal_path.pdf
Photomultiplier Tube Lab Instructions

stat1.pdf  “Errors and Statistics” (52 pages, by James Graham)
statistics1.pdf “Statistics, Probablility Distribution & Error” (42 pages, PowerPoint by James Graham)


Pictures (click to enlarge) Info, Schematics, Drawings, Software
Photomultiplier/LED box

PMTPMT box

Description
(pdf) Photomultiplier/LED box schematic
(pdf) H5773 photomultiplier module datasheet
(pdf) Pulse Amplifier schematic
Discriminator, Squawker, Pulse-shaper

electronics

Description
(pdf) Discriminator schematic
(pdf) Squawker schematic
(pdf) Pulse-shaper schematic

rphot - Linux computer with counter card

electronics

Description



Software
Data can be aquired through IDL with the function savephotons.

SYNTAX:
result = savephotons(nsamples=200, dt=1,filename='data.txt')

result = 0    (if no data was saved)
result = 1    (if data was saved)

DESCRIPTION:
"savephotons" will request data from the Linux computer “rphot”. The data file will be a text file with a single column of integers. The number of integers will equal nsamples. Each integer represents the total photons counted during a period of dt.
 
DEFAULT:
nsamples = 100
dt = 1 (ms)
filename = 'photons.nsamples.dt.txt'

RESTRICTIONS:
0 <  nsamp  < 5e5
0.2 <  dt  
0 <= counts < 65535

ISSUE (error making connection):
If result = savephotons = 0 and there is a message "error making connection", then rphot doesn't have its server running.
To start the server on rphot:
  1. ssh ugastro@10.32.92.5
  2. startnet
  3. exit


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