Difference between revisions of "Total Absorption Counter"
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| − | + | == 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. | ||
| + | |||
| + | {| border=1 | ||
| + | |+ Table: Properties of CLAS TAC counter | ||
| + | |- bgcolor=#DFDFDF | ||
| + | ! width=400px | Property (source) !! width=400px | Value | ||
| + | |- | ||
| + | | Material (from Mahbub) || align=center | SF-5 Lead Glass | ||
| + | |- | ||
| + | | Composition by weigth (Web) || align=center | 55% PbO, 38% SiO2, 5% K2O, 1% NaO2 | ||
| + | |- | ||
| + | | Length (from Mahbub) || align=center | 40cm | ||
| + | |- | ||
| + | | Height (from Mahbub) || align=center | 20cm | ||
| + | |- | ||
| + | | Width (from Mahbub) || align=center | 20cm | ||
| + | |- | ||
| + | | Weight of lead-glass block || align=center | 65 kg | ||
| + | |- | ||
| + | | Density (Web) || align=center | 4.08 g/cm^3 | ||
| + | |- | ||
| + | | Radiation Length (Web) || align=center | ~25mm | ||
| + | |- | ||
| + | | Refractive index (Web) || align=center | 1.67270 | ||
| + | |- | ||
| + | | PMT (from Mahbub) || align=center | 5 inch Hamamatsu R1250 PMT | ||
| + | |} | ||
| + | |||
| + | |||
| + | |||
| + | == options considered earlier == | ||
| + | |||
* lead-glass counter array: | * lead-glass counter array: | ||
** efficiency ~100% | ** efficiency ~100% | ||
** to avoid radiation damage: rate < 100kHz using radiator of 10<sup>-5</sup> X<sub>0</sub> and ~100 pA beam | ** to avoid radiation damage: rate < 100kHz using radiator of 10<sup>-5</sup> X<sub>0</sub> and ~100 pA beam | ||
* Cerenkov counter (higher current - but probably lower efficiency) | * Cerenkov counter (higher current - but probably lower efficiency) | ||
Revision as of 15:36, 9 March 2017
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 (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)
