The plots show dT distributions for all data samples obtained in 2019 - 2021.
The statistics is 1k events per run.
dT is calculated as a half of difference
between Z of primary vertices positions reconstacted only with west TPC (ZW) and
Z reconstructed only with east TPC (ZE) divided on a drift velocity (DV),
i.e.
dT = 0.5 × (ZW - ZE)/DV.
The primary vertex is choosen as the highest rank vertex which does not have an other vertex with Z within 5 cm of the first one.
DEV2_newDB5
dT distributions for 2019/RF/9p2GeV, 2020/RF/9p8GeV_fixedTarget, and 2021/RF/dAu2020_2021 show double peak structure.
2019/RF/9p2GeV
3 run periods:
9p2GeV_2019 : 20190628.081931 => 179
9p2GeV_2019b: 20190702,144151 => 183
9p2GeV_2019c: 20190715,005141 => 196
2019/RF/9p8GeV_fixedTarget
2 run periods:
9p8GeV_fixedTarget_2020 : 20200130
9p8GeV_fixedTarget_2020b: 20200131
2021/RF/dAu200_201
3 run periods:
dAu200_2021 : 20210630 => 181
dAu200_2021b: 20210703 => 184
dAu200_2021c: 20210704 => 185
DEV2_newDB7, disable starTrigDelay correction from Data base
dT distributions for 2019/RF/9p2GeV, 2020/RF/9p8GeV_fixedTarget, and 2021/RF/dAu2020_2021 DO NOT show double peak structure.
DEV2_newDB8, new starTrigDelay correction from Data base.
Ignore rank,
match West Only with East Only primary vertices by the highest multiplicities,
ignore event with extra primary vertex withing 5 cm from the best one, and
fit in range ± 2 σ.
All corrected dT distributions have the most probable shift withim ~1 nsec.
Conclusions
x[
It has been observed an (DEV2_newDB5) additional modification (~1 time bucket) for trigger delays for the same trigger setup for different run periods.
With disable DB correction (DEV2_newDB7) additional modification (~1 time bucket) for trigger delays for the same trigger setup for different run periods has disapperead.
it was FALSE ALARM due to mismatching timing in Data Base. Thus the observed shifts have been atributed to time stamp misplacement due to multiple switching trigger conditions, which has not properly accounted.
>The time stamps have been corrected and checked (DEV2_DB8).
3 run periods:
2 run periods:
3 run periods:
