1 / 4

More Stuff about Discarded Events J. Eric Grove

More Stuff about Discarded Events J. Eric Grove. Tests on spare boards at NRL. Bench tests with AFEE teststand at NRL No GASU = no timestamps Found Discards assoc with Range switching of GCFE analog out ~140, 360, … ticks Release of virtual gnd by ADC after settling time

chipo
Download Presentation

More Stuff about Discarded Events J. Eric Grove

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. More Stuff about Discarded Events J. Eric Grove

  2. Tests on spare boards at NRL • Bench tests with AFEE teststand at NRL • No GASU = no timestamps • Found • Discards assoc with • Range switching of GCFE analog out • ~140, 360, … ticks • Release of virtual gnd by ADC after settling time • ~190 ticks (not yet seen in Grid) • Clocking out of range bits (?) • ~290 ticks (only HE in NRL tests) • FLE later than FHE • Caveats • Tests done through AFEE monitor BO box • Tests not done with flight timing • Tests done with thresholds at noise floor

  3. Tests on spare boards at NRL First data bit ADC startbit End of TACK delay • Readout cmd from TEM • CAL data to TEM • LE trig request to TEM • GCFE analog out Discard ~140 ticks Discard ~360 ticks ADC release

  4. Comments • Recall deadtime • 1-range deadtime is 530 ticks, dominated by GEM • CAL deadtime is ~470 ticks, of which final ~35 ticks is in rearranging/zero-suppressing of CAL data into TEM FIFO • CAL/AFEE activity is done ~1.7 us before TEM BUSY ends • CAL dominates deadtime of 4-range, zero-suppressed • Again, all AFEE activity is done ~1.7 us before TEM BUSY ends • Enough is enough. What do we do next? • The code exists to monitor within dead time. • Let’s start looking during live time. Look for non-Poisson. We already know that the rate is small, just from inspection of CAL-LO and CAL-HI rates. • Remember, we see 100% retrigger during deadtime • Remember, even without analysis we see <few% during livetime. • This CANNOT be a big issue!

More Related