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Test Results Of Chamber L2C0#3 [message #997]

Thu, 30 September 2004 15:33

Sascha Freuen
Messages: 9
Registered: August 2004
Location: Heidelberg PI

occasional visitor

From: *kip.uni-heidelberg.de

Dear All

As an example, the results of testing chamber l2C0#3 are shown below (leakrate, gain curve, gain uniformity)

1.Leakrate
==========
The oxygen content within the chamber is measured in intervals of 5 minutes.
The asymptotic value is an indicator of the leakrate.
The flow rate was set at 10 l/h which leads to a time constant of ~4h
Fit : f(x)=a+b*exp(-c*x)

http://img48.exs.cx/img48/8567/leak_l2c0_3_glue.gif

http://img48.exs.cx/img48/6715/leak_l2c0_3_glue_log.gif

2.Gain Curve
============
The anode voltage is increased in steps of 20 V starting at 1000 V up to 1600 V.
At each step the anode current is recorded.
Fit : f(x)=a+b*exp(c*x)

http://img48.exs.cx/img48/3762/gaincurve_L2C0_3_glued_Sr.gif

http://img48.exs.cx/img48/2908/gaincurve_L2C0_3_glued_Sr_log.gif

3.Gain Uniformity
=================
There are two different measurement modes:

1. 1D scans with 4mm steps .Here you can clearly see the radiator bars, which absorb very strongly

1.1 4mm steps scan in z-direction at two different phi positions

http://img48.exs.cx/img48/4381/GainUni_L2C03_4mm_steps_horizontal_scan.gif

1.2 4mm steps scan in phi-direction at two different z positions

http://img48.exs.cx/img48/264/GainUni_L2C03_4mm_steps_vertical_scan.gif

2. A full 2D scan with 4cm equidistant steps. Here one can only see the radiator bar in the middle very clearly, due to the bigger step size.

http://img48.exs.cx/img48/4880/GainUni_L2C0_3_glued.gif

[Updated on: Tue, 01 February 2005 15:53]

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Re: Test Results Of Chamber L2C0#3 [message #1029 is a reply to message #997]

Tue, 12 October 2004 10:00

Harald Appelshaeuser
Messages: 39
Registered: March 2004
Location: GSI

continuous participant

From: pb-d-128-141-42-34.cern.ch

Dear Sascha,

very impressive pictures indeed. Just on question: in all cases the X-ray tube was used for irradiation?

Regards, Harry

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Re: Test Results Of Chamber L2C0#3 [message #1032 is a reply to message #1029]

Tue, 12 October 2004 19:32

Sascha Freuen
Messages: 9
Registered: August 2004
Location: Heidelberg PI

occasional visitor

From: *kip.uni-heidelberg.de

Dear Harry

For the gain curve measurement the Sr90 source was used.

Regards
Sascha

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