Difference between revisions of "Sampling Calorimeter"

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(Scheme of cables)
(Trigger)
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===Trigger===
 
===Trigger===
 
This is the flow chart for the current trigger logic. We are using 3 scintillators; 1 double sided (2PMTs) on top, and 2 separate scintillators on bottom. The difference between threshold voltages is to match gains, this was not done by adjusting HV since presently using HV units with dual outputs for one HV setting.
 
This is the flow chart for the current trigger logic. We are using 3 scintillators; 1 double sided (2PMTs) on top, and 2 separate scintillators on bottom. The difference between threshold voltages is to match gains, this was not done by adjusting HV since presently using HV units with dual outputs for one HV setting.
[[Image:Trigger_logic_2-5-13.png|none|300px|Trigger Logic Chart]]
+
[[Image:Trigger_logic_2-5-13.png|none|thumb|300px|Trigger Logic Chart]]
  
 
=== Scheme of cables ===
 
=== Scheme of cables ===
 
Scheme of the HERA-B modules. The orientation is as follows: top view with the rack modules at its left. Each module is indicated by its nomenclature (explained above), the DAQ and HV cable number (in red) and the signal cable (sgn).
 
Scheme of the HERA-B modules. The orientation is as follows: top view with the rack modules at its left. Each module is indicated by its nomenclature (explained above), the DAQ and HV cable number (in red) and the signal cable (sgn).
 
[[Image:Test-scheme.png|none|thumb|200px|Red: the number of the channel (for DAQ and HV label). Sgn: cable signal label.]]
 
[[Image:Test-scheme.png|none|thumb|200px|Red: the number of the channel (for DAQ and HV label). Sgn: cable signal label.]]

Revision as of 15:00, 5 February 2013


Links

Test setup

Nomenclature of the modules (could be changed)

In order to identify the different modules, the following structure is used:

X-YY-Z

with:

  • X = O (outer) or M (middle)
  • YY= 01, 02, 03, 04 ...
  • Z (only Middle modules) = A, B, C, D

HV control

  • Testing HV supply

Light Leaks sealing

The modules were sealed from light leaks with the use of black tape. To check the sealing, the output of the PMT was measured with an micro-amperimeter, before and after the cover with tape. In top of the pipe, where the PMT is allocated, a gum stopper with slits for the cables, are placed. After many checks it was found that:

  • the main light leak come for the joint of the module with the PMT allocation pipe. (Covering it, reduce the current drain from PMT aproximatly in 1-2 orders of magnitude)
  • covering the cap of the pipe, doesn't show significant improve.
  • covering with tape the side corners of the module, the joint of the top and bottom plastic caps and the union of the pipe with the module reduce the current drain from PMT in 4-5 orders of magnitude.

Outer Modules

For the outer modules, the same PMT was used, with a voltage of 1000 V (max 1900 V) to avoid damage to the PMT.

Module Current before Current after
O-01 15.2 μA 0.3-0.2 nA
O-02 10.9 μA 0.3-0.1 nA
O-03 48.5 μA 0.7-0.5 nA
O-04 N/A 2-1.7 nA
O-05 34.4 μA 2-1.4 nA

Middle Modules

For the middle modules, the same PMT was used, with a voltage of 1000 V (max 1900 V) to avoid damage to the PMT.

Module Current before Current after
M-01-A 10.9 μA ~0.5 nA
M-01-B 24.2 μA ~0.2 nA
M-01-C 20.9 μA ~0.2 nA
M-01-D 7.5 μA ~0.2 nA
M-02-A 38.5 μA ~0.7 nA
M-02-B 13.1 μA ~0.4 nA
M-02-C 30.5 μA ~0.3 nA
M-02-D 10.7 μA ~0.2 nA
M-03-A 23.9 μA ~0.7 nA
M-03-B 6.45 μA ~0.6 nA
M-03-C 3.8 μA ~0.3 nA
M-03-D 19.2 μA ~0.3 nA
M-04-A 13.2 μA ~0.7 nA
M-04-B 6.69 μA ~0.5 nA
M-04-C 5.3 μA ~0.5 nA
M-03-D 7.8 μA ~0.45 nA

Trigger

This is the flow chart for the current trigger logic. We are using 3 scintillators; 1 double sided (2PMTs) on top, and 2 separate scintillators on bottom. The difference between threshold voltages is to match gains, this was not done by adjusting HV since presently using HV units with dual outputs for one HV setting.

Trigger Logic Chart

Scheme of cables

Scheme of the HERA-B modules. The orientation is as follows: top view with the rack modules at its left. Each module is indicated by its nomenclature (explained above), the DAQ and HV cable number (in red) and the signal cable (sgn).

Red: the number of the channel (for DAQ and HV label). Sgn: cable signal label.