PMT Calibration R.Sawada 7/Jan/2007 Time calibration Method was talked at the previous meeting. The problems which was shown before were because I used PMTs in shadow from LED. 3 Distance [cm] Time [nsec] 4 Time offset and DRS channel According to Matthis, there is similar dependence in DC data. Chip:0Chip:1 5 Time offset and DRS board Crate:4Crate:5 Slot:2 There is small correlation. This was not expected because time difference due to electronics is corrected by using clock analysis. This can be variation of cable length in liquid xenon. (due to temperature co-efficient) 6 Time distribution before calibration Distance [cm] Time [nsec] Crate:4,Chip0 Crate:4,Chip1 Crate:5,Chip0 Crate:5,Chip1 Crate:5,Slot12 7 Time distribution before calibration Distance [cm] Time [nsec] 8 Result Time offset [nsec]Time offset uncertainty [nsec] One entry is one PMT This result is available in analysis and simulation. This number is uncertainty of measurement of one LED. Average is 1/sqrt(2)-1/sqrt(4) better. Q.E. Analyzed by using a task developed by Pisa group, with my small modification. 10 PMT Nphe fit (Same as LP) Gaussian when mean of nphe > 20 Poisson x Gaussian when mean of nphe < 20 Sigma of Gaussian is obtained from pedestal events 11 gas alpha Noise Outer wall alpha Wire alpha + Top/Bottom wall alpha Qsum2 > 2500 12 liquid alpha 13 Data:MC One graph is one PMT. One point is one alpha. Gas data (1/10 statistics, full statistics analysis is still running) 14 Data:MC One graph is one PMT. One point is one alpha. Liquid data (full statistics) 15 Result Q.E. liquid Full statistics of gas is running. Q.E. in liquid Q.E. in LP or Pisa 16 Summary Time calibration was done in psec uncertainty. Result is available Speed of light observed on Inner/Outer and lateral is slightly different. Q.E. estimation using liquid data was done. Gas will be finished soon. Result will be available in 1-2 days. Uncertainty is currently fitting error of data v.s. MC. It looks rather small. I will check the code again. I used MC result produced by Pisa group. I will check it with my MC. (It must be same, because we are using the same MC software.) PMT calibration was almost finished. I will proceed to absorption length estimation, Q.E. estimation dependence on geometry (check of MC), reconstruction and detector calibration. 1/sqrt(2) ~ 1/sqrt(4)