Difference between revisions of "IAC 2-29-08"

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|431||  0" from feedthrough , Sense wire at 1450 Volts
 
|431||  0" from feedthrough , Sense wire at 1450 Volts
 
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|432||  0" from feedthrough , Sense wire at 1500 Volts
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|432||  0" from feedthrough , Sense wire at 1500 Volts, Metalica (ADC6; C-convention) sees overflows and looks hot on scope compared to Plastika (ADC8: in ntuples)
 
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|432||  -1" from feedthrough (beam should miss chamber), Sense wire at 1500 Volts
 
|432||  -1" from feedthrough (beam should miss chamber), Sense wire at 1500 Volts
 
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Revision as of 16:41, 29 February 2008

Leap Day run

DC setup

This time the Sense wire HV is set to 1500 to start

90/10 ArCo2

HV settings
Wire Volts current ([math]\mu[/math]A)
Sense 1500
Field -750
Guard 750

DC preamp at 5.6 Volts


Go Back

Beam Line Configuration

A 1/4 inch diameter collimater is placed in the experimental cell just after a Helium bag inserted in the wall. A 2 cm thick scintillator is place over the beam downstream side of the collimator aligned using a laser. A 1 kG magnet placed after the drift chambers deflects charged particles onto a large scintillator paddle. A coincidence is required between the two scintillators.


Increased beam energy from 10 MeV to 12 MeV due to expected energy loss in front scintillator.

Runs

Decided to increase beam current until up to 10% of events in front scintilaltor hit back scintillator. Ran in OR mode so a software coincidence can be formed based on measurement in ADC15 (ADC14 in C convention).

Run # Description
431 0" from feedthrough , Sense wire at 1450 Volts
432 0" from feedthrough , Sense wire at 1500 Volts, Metalica (ADC6; C-convention) sees overflows and looks hot on scope compared to Plastika (ADC8: in ntuples)
432 -1" from feedthrough (beam should miss chamber), Sense wire at 1500 Volts