Difference between revisions of "Minutes 060609"
From GlueXWiki
| Line 1: | Line 1: | ||
''' Notes for item 2, tagger and trigger timing, etc''' (from EJW): | ''' Notes for item 2, tagger and trigger timing, etc''' (from EJW): | ||
| − | 1. We should install He bags; need | + | 1. We should install He bags; need to submit requirements doc to H-B for this and other beamline components |
| − | incl. radiator thickness, collimator size, etc. | + | incl. radiator thickness, collimator size, pair-spec and other magnet needs, etc. |
2. Tagger trigger timing (thanks to Eugene Pasyuk): | 2. Tagger trigger timing (thanks to Eugene Pasyuk): | ||
| − | 20 ns transit time in PMT | + | 20 ns transit time in T-counter PMT |
50 ns cable to CFD | 50 ns cable to CFD | ||
10-15 ns internal CFD | 10-15 ns internal CFD | ||
| Line 17: | Line 17: | ||
250 ns signal delay electron hits radiator until Master-OR arrives at our rack | 250 ns signal delay electron hits radiator until Master-OR arrives at our rack | ||
| − | Note that photon flight time to alcove is approx 100 ns (check with Mike Zarecky). If I recall, | + | Note that photon flight time to alcove is approx 100 ns (check with Mike Zarecky). Also note that T-counter |
| − | Richard said RadPhi has both 250 ns cables and 80 ns cables running from the alcove to the RadPhi racks. | + | cables are trimmed to give equal time signal at L-R coincidence module. |
| + | |||
| + | If I recall, Richard said RadPhi has both 250 ns cables and 80 ns cables running from the | ||
| + | alcove to the RadPhi racks. | ||
Still to be determined: BCAL signal timing, time to create BCAL trigger, length of cable running from | Still to be determined: BCAL signal timing, time to create BCAL trigger, length of cable running from | ||
forward carriage back to tagger, etc. | forward carriage back to tagger, etc. | ||
| − | 3. Tagger uses LeCroy 1877 multi-hit and CAEN pipelined TDC's; both run in common-stop mode | + | 3. Tagger uses LeCroy 1877 multi-hit and CAEN pipelined TDC's; both run in common-stop mode. |
4. CAEN V792 ADC (BCAL readout) is slowest and sets front-end busy time. May skip busy and just | 4. CAEN V792 ADC (BCAL readout) is slowest and sets front-end busy time. May skip busy and just | ||
use front-end-busy-timer in TS, as V792 has fixed digitization time of approx 7 microsec. | use front-end-busy-timer in TS, as V792 has fixed digitization time of approx 7 microsec. | ||
Revision as of 09:06, 9 June 2006
Notes for item 2, tagger and trigger timing, etc (from EJW):
1. We should install He bags; need to submit requirements doc to H-B for this and other beamline components
incl. radiator thickness, collimator size, pair-spec and other magnet needs, etc.
2. Tagger trigger timing (thanks to Eugene Pasyuk): 20 ns transit time in T-counter PMT 50 ns cable to CFD 10-15 ns internal CFD 5 ns cable to L-R coincidence module 5 ns internal coincidence module 10 ns cable to Master OR module 20 ns internal Master OR 80 ns cable to forward carriage 50 ns patch cables from forward carriage to BCAL test trigger rack ----- 250 ns signal delay electron hits radiator until Master-OR arrives at our rack Note that photon flight time to alcove is approx 100 ns (check with Mike Zarecky). Also note that T-counter cables are trimmed to give equal time signal at L-R coincidence module.
If I recall, Richard said RadPhi has both 250 ns cables and 80 ns cables running from the alcove to the RadPhi racks. Still to be determined: BCAL signal timing, time to create BCAL trigger, length of cable running from forward carriage back to tagger, etc.
3. Tagger uses LeCroy 1877 multi-hit and CAEN pipelined TDC's; both run in common-stop mode.
4. CAEN V792 ADC (BCAL readout) is slowest and sets front-end busy time. May skip busy and just
use front-end-busy-timer in TS, as V792 has fixed digitization time of approx 7 microsec.
