Revision as of 00:13, 6 November 2013

file dir

on dropbox

https://www.dropbox.com/sh/365le2o93vpn14e/yM3akCdLSK/readout

signal estimation for preshower

• condition
  • 22 photoelectrons per MIP from LHCb test in 2005 with 12x12x1.5cm module [1], 105 photoelectrons per MIP from LHCb test around 2000 with 4x4x1.5cm module and 15% PMT QE [2]. We take the later result as 22. Our 2cm preshower scintilator is 33% thicker than 1.5cm in LHCb PS, so we assume 30 photoelectrons for SoLID PS MIP
  • in SoLID preshower, one MIP is 6MeV, max signal is 200MeV, (refer to the preshower response plot in SoLID pCDR). If we plan to cover 6 - 240MeV which is 1 - 40 MIP, then photoelectrons from PS range is 30-1200
  • pulse full width 20ns according to scope picture from Simona's test of H8500C (slide 26 of talk). According to LHCb study, pulse shape has many variation and 25ns only covers about 85% of pluses on average. We assume 30ns.
  • Simplify pluse shape as a triangle shape, then pulse height is about 2 times pulse area
  • 50 ohm matching
  • at 1000V, MAPMT H10966 has gain 3e5 (comparing to MAPMT H8500 has gain 1.5e6)
  • At WLS (Kurary Y11) emission peak 476nm, QE of MAPMT H10966 25%, MAPMT H8500 15%, MAPMT H7546 15%
  • both MAPMT H10966 and H8500C has anode uniformity (=gain*photocathode sensitivity) 1:3 in its spec sheet (Simona's test confirms it). H7546 has 1:3 according to LHCb test, but it has 1:5 according its spec. We assume 1:3

• result without uniformity problem
  • pulse height min 30*3e5/30e-9*1.6e-19*50*2=0.005V
  • pulse height max 1200*3e5/30e-9*1.6e-19*50*2=0.192V
  • dynamic range 40

• result with 1:3 uniformity problem
  • pulse height min 30*3e5/30e-9*1.6e-19*50*2=0.005V
  • pulse height max 1200*3e5/30e-9*1.6e-19*50*2*3=0.576V
  • dynamic range 120

• conclusion
  • pulse height max < flashADC limit 2V
  • 12 bit ADC with 4096 channel like the Jlab flasADC can cover the dynamic range about 120 if a MIP is at channel 30

MAPMT crosstalk

• info
  • MAPMT has crosstalk between pixels. It's a effect combines optical and electronic leaks
  • Hamamatsu gives spec for H8500/H10966 max 3.5%, H7546 typical 2%
  • LHCb used fiber to test it, Hamamatsu used a lamp with filter, They both include the anode uniformity effect already
  • For H7546 with R5900-00-M64, LHCb test around 2000 [3] shows 20-25% crosstalk and LHCb test in 2005 [4] has max 2.5%
  • For LHCb Hamamatsu H7546 with R7600-00-M64MOD, LHCb test in 2007 [5] shows 2% after 21 out of 200 unit replaced by Hamamatsu

• • SoLID PS signal are very localized and dominated by pions
  • SoLID PS signal has 1MIP of Pion and electron peak at 10MIP and goes up to 40MIP, (refer to the preshower response plot in SoLID pCDR)
  • Assume H10966 with 3.5% crosstalk, electron peak deposition gives 10*3.5%=0.35MIP, electron max deposition gives 40MIP*3.5%=1.4MIP. If we are cutting on 3-4MIP for PS, it should be a small effect.
  • comparing to LHCb, it has a range of 1-50MIP by and covered by 10bit ADC with 1000 channels [6]

• channel arrangement
  • choice 1, same radius on same MAPMT to have same background level
  • choice 2, same sector on same MAPMT and match calorimeter module arrange because modules in a cluster will be summed anyway

• how will background affect things

difference between LHCb and SoLID

• LHCb SPD and PS are both 1.5cm thick. SoLID SPD is 0.5mm thick, PS 2cm thick. SoLID has not photon background.
• LHCb SPD ans PS are in trigger. SoLID SPD and PS are not in trigger. flashADC can't be used for LHCb if it were available. (?)
• LHCb has to use 25ns time window to match its 40MHz bunch crossing time, only 85% of its signal is integrated. SoLID has more freedom to choose longer time windows like 30ns and thus integral 100% signal.

MAPMT info

• file location
  • general at https://www.dropbox.com/sh/365le2o93vpn14e/2at980iq-y/readout/MAPMT
  • LHCb related at https://www.dropbox.com/sh/365le2o93vpn14e/g_v9IHvaLF/other_calorimeter/LHCb

• Our Study
  • W&M study of LHCb MAPMT [7]
  • SDU summary of Hamamatsu MAPMT [8] [9]

• LHCb Study
  • LHCb structure before ECAL is 1.5cm SPD + 2.5X Lead + 1.5cm PS, MAPMT H7546 with special front end electronic for readout, 10bit ADC for PS, 1bit for SPD
  • LHCb Hamamatsu H7546 with R5900-00-M64 (12 stages) test in 2005 [10], 2000 [11]
  • LHCb Hamamatsu H7546 with R7600-00-M64MOD (8 stages) mass characterization in 2007 [12]
  • H7546 as a package may have involved from R5900-00-M64 to R7600-00-M64MOD inside

• Hamamatsu info
  • MAPMT assembly from hamamatsu http://www.hamamatsu.com/jp/en/product/category/3100/3002/index.html
  • H7546 is a package name and its current spec sheet mentions R7600-M64 PMT inside[13]
  • The new MA-PMT, H12700 [14], is still under development. We hope to be able to release it by the end of this year
  • H8500's uniformity map in Figure 3 on page 2 of its datasheet [15]. By standard spec, the non-uniformity has to be less than 1:3. It reflects variation in anode sensitivity, which is gain x photocathode sensitivity. The 1:3 means that we record the relative output of all anodes: the lowest output must be larger than 1/3 of the highest one.

• other
  • CLAS12 RICH H8500C test, including crossstalk result (Hoek_H8500_Characterization.pdf)
  • CLAS12 RICH has some H7546 test done also (Montgomery_NPESeminar_150911.pdf)
  • CLAS12 RICH frontend (130626_RICH_Tech_Rev_FrontEnd.pdf)
  • CLAS12 RICH DAQ (HallB_RICH_DAQ_June2013.pdf)
  • CLAS12 RICH review report (Rich_Tech_Review_report.pdf)
  • SBS coordinate director, similar to SoLID EC SPD (CDet-talk-SBS-MeetingJune2013-Sarty.pptx)