Total Absorption Counter
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Revision as of 15:38, 9 March 2017 by Hovanes (Talk | contribs) (→CLAS Total absorption counter used for PrimEx)
CLAS Total absorption counter used for PrimEx
The table below summarizes the information I obtained from various sources about the TAC counter that GlueX borrowed from CLAS.
Property (source) | Value |
---|---|
Material (from Mahbub) | SF-5 Lead Glass |
Composition by weigth (Web) | 55% PbO, 38% SiO2, 5% K2O, 1% NaO2 |
Length (from Mahbub) | 40cm |
Height (from Mahbub) | 20cm |
Width (from Mahbub) | 20cm |
Weight of lead-glass block | 65 kg |
Density (Web) | 4.08 g/cm^3 |
Radiation Length of material (Web) | ~25mm |
Refractive index (Web) | 1.67270 |
PMT (from Mahbub) | 5 inch Hamamatsu R1250 PMT |
options considered earlier
- lead-glass counter array:
- efficiency ~100%
- to avoid radiation damage: rate < 100kHz using radiator of 10-5 X0 and ~100 pA beam
- Cerenkov counter (higher current - but probably lower efficiency)