TOFp / pvpd / TOFr in Run-III W.J. Llope for the STAR TOF group STAR Collaboration Meeting, BNL, 2/26/2003

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1 TOFp / pvpd / TOFr in Run-III W.J. Llope for the STAR TOF group STAR Collaboration Meeting, BNL, /6/3 outline: Run-III (d+au) hardware... chronology for days hit patterns integrated # s of events and TOFx hits... hit patterns movie... preliminary pvpd performance... efficiency & Nhits... preliminary start resolution... early results from the stop side Run-II (Au+Au) see talk in spectra PWG tomorrow

2 TOFp Detectors for Run III pvpd and TOFp as in Run- first run for MRPC TOFr in STAR pvpd at run- pp gain set local trigger.and. TOFp pvpd East pvpd West east TPC ~6 o TOFr 4 slats ~8 cm /slat ~3.k cm total 8 modules 68 MRPC chs 7 digitized ~ cm /cell ~.4k cm total

3 TOF Systems Event Totals (days 4-) Totals by Day Number(*) Running Totals by Day Number(*)? snow storm 4 3 snow storm pvpd evts TOFp hits TOFr hits (*) day number is that when localmon data are saved to specific file names. i.e. gaps in the above don t imply tof was down (probably machine was though)... local trigger efficiency ~8% (stable). so far: ~.M pvpd physics events individual ADC and TDC distributions ~M total TOFp hits are generally fine - some scattered bad chs ~.M total TOFr hits (all freon-only)

4 Hit Patterns to date days - localmon sampling rate = % TDC Hit Pattern, w/ ADC hit ADC Hit Pattern, w/ TDC hit TOFp TOFr pvpd so far ~4k hits per TOFp slat ~k hits per TOFr cell the usual handful of sick TOFp chs 3-4 TOFr chs w/ problems (not all necessarily detector problems)

5 brief chronology of TOF Systems in Run 3 (days 9-) Date: Day: Jan 9 9 Run 486, first test of TOF-DAQ communication in a test run TOF systems now under Shift Control and involved in running Trouble w/ TOFr HV tripping at beginnings of fills, lost TOFr for some spills... Jan TOFr Mapping Problem seen, (re)maps defined to fix problem in software Jan 3 3 pvpd now at correct gain set and controllable from SC GUIs (Dennis Reichold et al.) Jan 7 7 TOFr Re-Ramp functionality implemented. TOFr never misses spills now... Jan 8 8 TOFp chokes - FEE failure... Jan 3 3 Scheduled Access w/ East Pole-Tip off. TOFp fixed. all signal paths strobed... (mapping problem) detailed study of all TOFr cabling - no problems seen! Feb 6 37 TOFp ADC # dies, replaced w/ one w/out preset pedestals... Feb 43 First integration of TOFp HV, TOFr HV, and TOFr Gas Monitor in STAR SC GUIs... Feb 3 44 TOFp current limit problem appears - fixed same day in surprise access... TOFr Mapping problem traced to two bad TDCs - replaced. Mapping problem gone. Snow Feb Starting to implement local logic for pvpd- and TOFr-based triggers... timing tests... Feb 3 4 Data looks wierd (hear lots going on re: L and DAQ...) Feb 4 Data looks better (no local changes), but now seeing more L timeouts than expected... increased local L time-out delay from.s to.s - huge improvement. TOFr TDC #7 dies.. Feb 6 7 Scheduled access... (replaced TOFr plat disc, TOFp ADC, TOFr TDC, tests) Hit Pattern Movie

6 pvpd in d+au pvpd East sees Gold ring sees Au fragmentation pvpd West sees Blue ring sees d fragmentation local trigger condition is.and.... No. Lit PMTs West these are localmon totals multiply by ten to get actual evt totals. so far (days 4-) nwvsne 3. Entries ~.M pvpd-triggered events (days 4-) East!= West 3. nwvsne 3.. Entries % % % No. Lit PMTs East No. Lit PMTs East 9% % 6% on average.3 hits West hits per event primarily single-particle timing... (ouch).4 hits East hits per event multi-particle timing... East chs should outperform West chs (vastly different environment on the start side as compared to Run s symmetric beams!)

7 pvpd resolution in minbias d+au East East East 3 e3a e3a Entries Entries vs ADC Mean 39.6 Mean.4 RMS 6.4 RMS 7. Underflow 7.36 Underflow 7.3 Overflow -4.3 Overflow / / 9 Prob.798 Prob.37 p p p p p p pass e3a Entries 6668 Mean 6. RMS 97.9 Underflow 3.3 Overflow / 9 Prob 7.977e-9 p p p e3b Entries 676 Mean 39. e3b Entries 6797 Mean.4 e3b Entries 6773 Mean 6.4 RMS 6.4 Underflow -.68 RMS 7. Underflow -.37 RMS 97.9 Underflow Overflow / 9 Overflow / 9 Overflow / 9 pass - Prob p p p.8e-6.34e-7 - Prob p p p 4.37e-6.33e-7 - Prob p p p.87e-6.479e e3c Entries 677 Mean 39. RMS 6.4 Underflow e3c Entries 67 Mean.4 RMS 7. Underflow -.99 e3c Entries 678 Mean 6.4 RMS 97.9 Underflow pass 3 - Overflow / 9 Prob p.88.6 p p 7.646e-7.66e-7 - Overflow / 9 Prob p.3. p p 9.387e-7.3e-7 - Overflow / 9 Prob p.36. p p.e-6.37e e3d Entries 673 Mean 39.6 e3d Entries 67 Mean.4 e3d Entries 6774 Mean 6.4 pass 4 - RMS 6.4 Underflow Overflow / 9 Prob p.494. p p.496e-7.73e-7 - RMS 7. Underflow -. Overflow / 9 Prob p p p.97e-7.e-7 - RMS 97.9 Underflow Overflow / 9 Prob p p p.e-7.369e ADC ADC ADC

8 dtdc_e3d dtdc_e3d dtdc_e3d Entries 68 Entries 68 Entries 68 3 Mean RMS Mean -.7 RMS Mean.49 RMS.96 3 Underflow 4 Overflow / 7 3 Underflow 446 Overflow / 7 3 Underflow 44 Overflow / 7 Prob Constant 3.388e Prob Constant 3.637e+4.3 Prob Constant 3.49e+4. Mean Sigma Mean Sigma Mean Sigma σ(- ) is ~.7 TDC chs, or ~3ps single detector resn on the East is ~4- ps σ ~ 74ps σ 3 ~ 6ps σ 4 ~ 8ps pvpd start resolution is better than expected i.e. more forward hits than expected may be harder to get the West calibrated to this level...

9 d+au Production underway (hurray!) production of TOF minidst underway (FG), so-called Match Ntuple for TOFp few days later full calibration of pvpd and TOFp then starts (few days) work also started on similar software for TOFr: Counts 3 the PID of TOFr (Lijuan Ruan) very preliminary no stop side corrections... PID Entries 46 Mean.4973 RMS Mass (GeV/c/c) first fully calibrated d+au results from TOFp+pVPD in ~ week...

10 Summary pvpd, TOFp, TOFr up and running well since Day ~4... no trips or other emergencies for the shift crew to deal with... various intermittant detector/electronics problems throughout but overall ~. M pvpd physics triggers (corresponds to M STAR events) ~M total TOFp Hits ~.M total TOFr Hits (all freon-only) ~4k hits/slat in TOFp ~k hits/cell in TOFr (add l penalties: ~.7 good starts * ~.3 primaries * Zvtx cut) a pvpd+tofr trigger would be immense boost to TOFr data set (see following talk) pvpd timing resolution in d+au is better than expected... in range from -8ps minbias... ~.3 hits/event on West ~.4 hits/event on East East will outperform West... Production data becoming available expect fully calibrated /β vs p spectra from pvpd+tofp in ~- weeks... pvpd+tofr spectra soon thereafter... Plans for rest of run. TOFp and pvpd TOFr no changes - just take data... Want to switch to Freon + ~% isobutane in less than ~ week... Want pvpd+tofr triggered data runs for both gas mixtures...