S-2S MEMO WC detector test 2015/6/10 Toshiyuki Gogami

Contents  y-position dependence  HV dependence  Geometrical factor (Top and Bottom)  PMT individual difference (2 PMTs)

y-position dependence (NEW) In the previous measurement, optical grease was taken off day by day …  NPE reduction with time. In this time, the optical grease was changed to BC- 630 which has higher viscosity, instead of BaF 2.  No NPE reduction with time.  Proper y-dependence measurement (run60 – run82, 5/21 – 5/26)

LED calibration (run60 – run82) During this period, an air conditioner was kept turning ON. ~ 2% fluctuation  Systematic error

y - dependence Results (run60 – run82)

NPE dependence on HV setting HV settings were varied from V to V. (Run83 – Run97, 5/26 – 5/28) NPE dependence on HV setting

No dependence within the errors.

PMT Swapping (Run98 – run118, 6/1 – 6/8) To see 1.Geometrical factor (Top and Bottom difference) 2.PMT performance difference

Schematic drawing of PMT swapping test H UV ZK6922 H UV ZK6920 Trigger H UV ZK6920 H UV ZK6922 NPE = 106.5± ± ± ±0.5

Schematic drawing of PMT swapping test H UV ZK6922 H UV ZK6920 Trigger H UV ZK6920 H UV ZK6922 NPE = 106.5± ± ± ±0.5 Compare1 Geometrical factor (Top and Bottom difference) Compare2

Geometrical factor (Top and Bottom difference) Compare1 Compare2 = BOTTOM / TOP TOP is better than Bottom by 12%. This would be caused by how the Tyvek sheet was attached inside the container.

Schematic drawing of PMT swapping test H UV ZK6922 H UV ZK6920 Trigger H UV ZK6920 H UV ZK6922 NPE = 106.5± ± ± ±0.5 Compare1 PMT performance difference Compare2

PMT performance difference Compare1 Compare2 = ZK6520 / ZK6522 ZK6520 is able to detect more NPE than ZK6522 by ~5%

Summar y

Backup

NPE results (HV dependence) /../ROOT/run84.dat.root /../ROOT/run84.dat.root /../ROOT/run84.dat.root /../ROOT/run96.dat.root /../ROOT/run96.dat.root /../ROOT/run96.dat.root /../ROOT/run87.dat.root /../ROOT/run87.dat.root /../ROOT/run87.dat.root /../ROOT/run93.dat.root /../ROOT/run93.dat.root /../ROOT/run93.dat.root

y-dependence (Phase 5)

TDC distribution of WC1 (ZK6922)

TDC distribution of WC1 (ZK6920)

TDC as a function of y

NPE width as a function of y

Timing width as a function of y

NPE vs. TDC ( 直接 PMT に入ったチェレンコフ 光とそうでない光がわけれるか も！ )