MiniPrototype CosmicRuns

Cosmic Coincidences

setup

Setup a cosmic coincidence experiment with two crossed scintillators that have the proto-type drift chambers sandwhiched between them.

Built 4 100 ns long delay cables. 2 for the PMTs and one for sense wire 7 on each of the drift chambers.

The top PMT is in channel 7 of the QDC and channel 16 of the scaler.

The Bottom PMT is on channel 8 of the QDC and channel 7 of the scaler.

Coincidence counts are recorded in channel 2 of the scaler.

Runs

Drift Chamber is off

Run 182: Ran with coincidence module in "OR" mode so if either paddle triggered the ADC was read out

Run 183: Switched coincidence module to "AND" mode and ran overnight.

12/23/07

Drift Chamber turned on with 90/10 ArCO2 and the voltages below

HV settings
Wire	Volts	current ([math]\mu[/math]A)
Sense	1500	19
Field	-800	19
Guard	800	0

Run 204: Scope was plugged into DC output (split signal)

12/24/07

Run 206: Unplugged scope and started this run

Drift Chamber turned on with 90/10 ArCO2 and the voltages below

HV settings
Wire	Volts	current ([math]\mu[/math]A)
Sense	1500	19
Field	-800	19
Guard	800	0

I had a bad ribbon cable on plastica. Ignore the results for Plastica. It was just a good pedestal measurement.

It looks like Metalica saw 2/3 of the cosmics seen by the Scintilaltors.

12/27/07

Run 207:

Scope picture of a Cosmic Coincidence event triggered by and AND between the top and bottom scintillator.

Drift Chamber turned on with 90/10 ArCO2 and the voltages below

HV settings
Wire	Volts	current ([math]\mu[/math]A)
Sense	1500
Field	-800
Guard	800

12/28/07

Run 208:

Increased Gate width from 200 ns to 800 ns after realizing that the drift chamber pulses could be that wide. I also removed the 100 ns decay line on sense wire #4 of both chambers. The PMT pulses still have a 100 ns delay line in.

Drift Chamber turned on with 90/10 ArCO2 and the voltages below

HV settings
Wire	Volts	current ([math]\mu[/math]A)
Sense	1500
Field	-800
Guard	800

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