Run 8 BPRS Calibration

Parent for Run 8 BPRS Calibration done mostly by Jan

01 DB peds R9069005, 9067013

 Pedestal residua for 434 zero-bias events from run 9069005.

The same pedestal for all caps was used - as implemented in the offline DB.

 

Fig 1.

Fig 2.  Run 9067013, excluded caps >120.  All 4800 tiles, pedestal residua from 100 st_zeroBias events. Y-axis [-50,+150].

Fig 3.  Run 9067013, excluded caps >120. Pedestal corrected spectra for all 4800 tiles, 10K  st_physics events. Y-axis [-50,+150].

Dead MAPMT results with 4 patches 4 towers wide.

Fig 4.

Run 9067013, excluded caps >120. 

Zoom-in Pedestal corrected spectra, one ped per channel.

Top 10K st_physics events (barrel often triggered)

Bottom pedestal residua 100 st_zeroBias events

Fig 5.

Run 9067013, input =100 events, accept if capID=124 , raw spectra.

There are 4 BPRS  crates, so 1200 channels/crate.  In terms of softIds it's

PSD1W:  1-300 + 1501-2400
PSD19W: 301-1500
PSD1E:  2401-2900 + 4101-4800
PSD20E: 2901-4100

Why only 2 channels fired in crate PSD20E ?

02 pedestal(capID)

 Run 9067013, 30K st_physics events, spectra accumulated separately for every cap.

Top plot pedestal (channel), bottom plot integral of pedestal peak to total spectrum.

 


Fig 1. CAP=122


Fig 2. CAP=123


Fig 3. CAP=124


Fig 4. CAP=125


Fig 5. CAP=126


Fig 6. CAP=127



Fig 7. Raw spectra for capID=125. Left: typical good pedestal, middle: very wide pedestal, right: stuck lower bit.

For run 9067013 I found: 7 tiles with ADC=0, ~47 tiles with wide ped, ~80 tiles with stuck lower bit.

Total ~130 bad BPRS tiles based on pedestal shape, TABLE w/ bad BPRS tiles




Fig 8. QA of pedestals, R9067013, capID=125. Below is 5 plots A,...,F all have BPRS soft ID on the X-axis.

A: raw spectra (scatter plot) +  pedestal from the fit as black cross (with error).

B: my status table based on pedestal spectrum. 0=good, non-zero =sth bad.

C: chi2/DOF from fitting pedestal, values above 10. were flagged as bad

D: sigma of pedestal fit, values aove 2.7 were flagged as bad

E: integral of the found pedestal peak to the total # of entries. On average there was ~230 entries per channel.



Fig 9. BPRS pedestals for 'normal' caps=113,114,115 shown with different colors


Fig 10. BPRS pedestals for caps=100..127 and all softID , white means bad spectrum, typical stats of ~200 events per softID per cap


Fig 11. BPRS:" # of bad caps , only capID=100...127 were examined.


Fig 12. BPRS:" sig(ped)


Fig 13. BPRS:" examples of ped distribution for selected channels. Assuming for sing;e capID sig(ped)=1.5, the degradation of pedestal resolution if capID is not accounted for would be: sqrt(1.5^2 +0.5^2)=1.6 - perhaps it is not worth the effort on average. There still can be outliers.

 

03 tagging desynchronized capID

BPRS Polygraph detecting corrupted capIDs.

Goal: tag events with desynchronized CAP id, find correct cap ID

Method: 

  1. build ped(capID, softID)
  2. pick one BPRS crate (19W)
  3. compute chi2/dof for  series capID+/-2
  4. pick 'best'  capID with smallest chi2/dof
  5. use pedestals for best capID for this crate for this event
  6. if best capID differs from nominal capID call this event 'desynchronized & fixed'

Input: 23K st_physics events from run 9067013.

For technical reason limited range of nominal capID=[122,126] was used, what reduces data sample to 4% ( 5/128=0.04).

Results:


Fig 1. ADC-ped(capID,softID) vs. softID for crate 1 (i.e. PSD19W) as is'. No capID corruption detection

 


Fig 2. ADC-ped(capID,softID) with capID detection & correction enabled. The same events.

 

Note, all bands are gone - the capID fix works.

Right: ADC-ped spectra: Black: 594 uncorrupted  events, red: 30 corrupted & fixed events.

 

The integral for ADC[10,70] are 2914 and 141 for good and fixed events, respectively.

141/2914=0.048;  30/594=0.051 - close enough to call it the same (within stats).

 

 

 

 


Fig 3. Auxiliary plots. 

 

TOP left: chi/dof for all events. About 1100 channels is used out of 1200 in served by crate 1. Rejected are bad & outliers.

TOP right: change of chi2/dof for events with corrupted & fixed capID. 

BOTTOM: frequency of capID for good & fixed events, respectively.

 

 


Conclusions:

  • BPRS-Polygraph algo efficiently identifies and corrects BPRS for corrupted capID, could be adopted to used offline .
  • there is no evidence ADC integration widow changes for BPRS data with corrupted capID.   

 

 


Table 1.

shows capIDs for the 4 BPRS crates for subsequent events. Looks like for the same event cap IDs are strongly correlated, but different.
Conclusion: if we discard say capID=125, we will make hole of 1/4 of barrel , different in every event. This holds for BPRS & BSMD.

capID= 83:89:87:90: eve=134 
capID= 1:4:11:3: eve=135 
capID= 74:74:81:72: eve=136 
capID= 108:110:116:110: eve=137 
capID= 68:72:73:75: eve=138 
capID= 58:55:65:64: eve=139 
capID= 104:110:106:101: eve=140 
capID= 9:6:8:15: eve=141 
capID= 43:37:47:46: eve=142 
capID= 120:126:118:122: eve=143 
capID= 34:41:41:40: eve=144 
capID= 3:0:126:2: eve=145 
capID= 28:33:28:30: eve=146 
capID= 72:64:70:62: eve=147 
capID= 2:6:7:5: eve=148 
capID= 22:32:33:24: eve=149 
capID= 8:4:5:124: eve=150 
capID= 23:17:17:19: eve=151 
capID= 62:57:63:61: eve=152 
capID= 54:53:45:47: eve=153 
capID= 68:75:70:67: eve=154 
capID= 73:79:73:72: eve=155 
capID= 104:98:103:103: eve=156 
capID= 12:5:13:10: eve=157 
capID= 5:10:10:2: eve=158 
capID= 32:33:27:22: eve=159 
capID= 96:102:106:97: eve=160 
capID= 79:77:72:77: eve=161 

 

04 BPRS sees beam background?

The pair of plots below demonstrates BPRS pedestal residua are very clean once peds for 128 caps are used and this 5% capID corruption is detected and fixed event by event.

 INPUT: run 9067013, st_phys events, stale BPRS data removed, all 38K events .


Fig 0. capID correction was enabled for the bottom plot. Soft ID is on the X-axis; rawAdc-ped(softID, capID) on the Y-axis.

 


Now you can believe me the BPRS pedestals are reasonable for this run. Look at the width of pedestal vs. softID, shown in Fig 1 below.

There are 2 regions with wider peds, marked by magenta(?) and red circle.

The individual spectra look fine (fig 2b, 2bb).

But the correlation of pedestal width with softID (fig 1a,1b) and phi-location of respective modules (fig 3a, 3b) suggest it could be due to the beam background at

~7 o'clock on the West and at 6-9 o'clock on the East.

 

 

 

05 ---- peds(softID,capID) & status table, ver=2.2, R9067013

INPUT: st_hysics events from run=9067013


Fig 1. Top: pedestal(softID & capID), middle: sigma of pedestal, bottom: status table, Y-axis counts how many capID had bad spectra.

Based on pedestal spectra there are 134 bad BPRS tiles

 


Fig 2. Distribution of pedestals for 4 selected softIDs, one per crate.

 


Fig 3. Zoom-in of ped(soft,cap) spectrum to see there is more pairs of 2 capID which have high/low pedestal vs. average, similar to the known pair (124/125).
Looks like such piar like to repeat every 21 capIDs - is there a deeper meaning it?
(I mean will the World end in 21*pi days?)


Fig 4. Example of MIP spectra (bottom). MIP peak is very close to pedestal, there are worse cases than the one below.

06 MIP algo ver 1.1

 TPC based MIP algo was devised to calibrate BPRS tiles.

Details of the algo are in 1st PDF,

example of MIP spectra for 40 tails with ID [1461,1540] are in subsequent 5 PDF files, sorted by MAPMT

 

Fig 1 shows collapsed ADC-ped response for all 4800 BPRS tiles. The average MIP response is only 10 ADC counts above ped wich has sigma of 1.5 ADC. The average BPRS gain is very is very low.

07 BPRS peds vs. time

Fig 1. Change of BPRS pedestal over ... within the same fill, see softID~1000

Pedestal residua (Y-axis) vs. softID (X-axis), same reference pedestals used from day 67 (so some peds are wrong for both runs)  were used both plots.

Only fmsslow events, no further filtering, capID corruption fixed in fly.

Top run 9066001, start 0:11 am, fill 9989

Bottom run 9066012, start 2:02 am, fill 9989

 

 

Fig 2. Run list. system config was changed between those 2 runs marked in blue.

Fig 3. zoom in of run 9066001

Fig 4. another example of BPRS ped jump between runs: 9068022 & 9068032, both in the same fill.

08 BPRS ped calculation using average

Comparison of accuracy of pedestal calculation using Gauss fit & plain average of all data.

The plain average method is our current scheme for ZS for BPRS & BSMD for 2009 data taking.

Fig 2. TOP: RMS of the plain average, using 13K of fmsslow-triggered events which are reasonable surrogate of minBias data for BPRS.
Middle: sigma of pedestal fit using Gauss shape
Bottom: ratio of pedestals from this 2 method. The typical pedestal value is of 170 ADC. I could not make root to display the difference, sorry.

09 BPRS swaps, IGNORING Rory's finding from 2007, take 1

This page is kept only for the record- information here is obsolete.

This analysis does not accounts for BPRS swaps discovered by Rory's in 2007, default a2e maker did not worked properly 

  • INPUT: ~4 days of fmsslow-triggered events, days 65-69
  • DATA CORRECTIONS:
    • private  BPRS peds(cap,softID) for every run,
    • private status table, the same , based on one run from day 67
    • event-by-event capID corruption detection and correction
    • use vertex with min{|Z|}, ignore ranking to compensate for PPV problem
  • TRACKING:
    • select prim tracks with pr>0.4 GeV, dEdX in [1.5,3.7] keV, |eta|<1.2
    • require track enters tower 1cm from the edge and exists tower at any distance to the edge
    • tower ADC is NOT used (yet)
  • 2 histograms of rawADC-ped were accumulated: for all events (top plot) and for BPRS tiles pointed by TPC track (middle plot w/ my mapping   & lower plot with default mapping)

There are large section of 'miples' BPRS tiles if default mapping is used: 3x80 tiles + 2x40 tiles=320 tiles, plus there is a lot of small mapping problems. Plots below are divided according to 4 BPRS crates - I assumed the bulk of mapping problems should be contained within single crate. 

 


Fig 1, crate=0, Middle plot is after swap - was cured for soft id [1861-1900]

   if(softID>=1861 && softID<=1880) softID+=20;
    else if(softID>=1881 && softID<=1900) softID-=20;

 

 


Fig2, crate=1, Middle plot is after swap - was cured for soft id [661-740]

  if(softID>=661 && softID<=700) softID+=40;
    else if(softID>=701 && softID<=740) softID-=40;


Fig3, crate=2, Middle plot is after swap - was cured for soft id [4181-4220].

But swap in [2821-2900] is not that trivial - suggestions are welcome?

 if(softID>=4181 && softID<=4220) softID+=40;
    else if(softID>=4221 && softID<=4260) softID-=40;

 

Fig4, crate=3, swap in [3781-3800] is not that trivial - suggestions are welcome?

 

 

10 -------- BPRS swaps take2, _AFTER_ applying Rory's swaps

 2nd Correction of BPRS mapping (after Rory's corrections are applied).

  • INPUT: ~7 days of fmsslow-triggered events, days 64-70, 120 runs
  • DATA CORRECTIONS:
    • private  BPRS peds(cap,softID) for every run,
    • private status table, excluded only 7 strips with ADC=0
    • event-by-event capID corruption detection and correction
    • use vertex with min{|Z|}, ignore PPV ranking, to compensate for PPV problem
    • BPRS swaps detected by Rory in 2007 data have been applied 
  • TRACKING:
    • select prim tracks with pr>0.4 GeV, dEdX in [1.5,3.7] keV, |eta|<1.2, zVertex <50 cm
    • require track enters tower 1cm from the edge and exist the same tower at any distance to the edge (0 cm)
    • tower ADC is NOT used (yet)
  • 3 2D histograms of were accumulated:
    •  rawADC-ped (softID)  for all events
    •  the same but only  for BPRS tiles pointed by QAed MIP TPC track 
    •  frequency of correlation BPRS tiles with MIP-like ADC=[7,30] with towers pointed by TPC MIP track

 

Based on correlation plot (shown as attachment 6) I found ~230 miss-mapped BPRS tiles (after Rory's correction were applied).

Once additional swaps were added ( listed in table 1, and in more logical for in attachment 3) the correlation plot is almost diagonal, shown in attachment 1.

Few examples of discovered swaps are in fig1. The most important are 2 series of 80 strips, each shifted by 1 software ID.

Fig 2 shows MIP signal shows up after shit by 1 softID is implemented. 

The ADC spectra for all 4800 strips are shown in attachment 2. Attachment 5 & 6  list basic QA of 4800 BRS tiles for 2 cases: only Rory's swaps and Rory+Jan swaps.

 


Fig 1. Examples of swaps, dotted line marks the diagonal. Vertical axis shows towers pointed by TPC MIP track. X-axis shows BPRS soft ID if given ADC was in the range [7,30] - the expected MIP response. Every BPRS tile was examined for every track, multiple times per event if more than 1 MIP track was found. 

Left: 4 sets of 4 strips needs to be rotated.                                              Right: shift by 1 of 80 strips overlaps with rotation of 6 strips.

 


Fig 2. Example of recovered 80 tiles for softID~2850-2900. Fix: softID was shifted by 1.


Fig 3. Summary of proposed here corrections to existing BPRS mapping


Table 1. List of all BPRS swaps , ver 1.0,  found after Rory's corrections were applied, based on 2008 pp data from days 64-70.

The same list in human readable from is here

Identified BPRS 233 swaps. Convention: old_softID --> new_softID 
389 --> 412 , 390 --> 411 , 391 --> 410 , 392 --> 409 , 409 --> 392 ,
 410 --> 391 , 411 --> 390 , 412 --> 389 , 681 --> 682 , 682 --> 681 ,
 685 --> 686 , 686 --> 685 ,1074 -->1094 ,1094 -->1074 ,1200 -->1240 ,
1220 -->1200 ,1240 -->1260 ,1260 -->1220 ,1301 -->1321 ,1303 -->1323 ,
1313 -->1333 ,1321 -->1301 ,1323 -->1303 ,1333 -->1313 ,1878 -->1879 ,
1879 -->1878 ,1898 -->1899 ,1899 -->1898 ,2199 -->2200 ,2200 -->2199 ,
2308 -->2326 ,2326 -->2308 ,2639 -->2640 ,2640 -->2639 ,2773 -->2793 ,
2793 -->2773 ,2821 -->2900 ,2822 -->2821 ,2823 -->2822 ,2824 -->2823 ,
2825 -->2824 ,2826 -->2825 ,2827 -->2826 ,2828 -->2827 ,2829 -->2828 ,
2830 -->2829 ,2831 -->2830 ,2832 -->2831 ,2833 -->2832 ,2834 -->2833 ,
2835 -->2834 ,2836 -->2835 ,2837 -->2836 ,2838 -->2837 ,2839 -->2838 ,
2840 -->2839 ,2841 -->2840 ,2842 -->2841 ,2843 -->2842 ,2844 -->2843 ,
2845 -->2844 ,2846 -->2845 ,2847 -->2846 ,2848 -->2847 ,2849 -->2848 ,
2850 -->2849 ,2851 -->2850 ,2852 -->2851 ,2853 -->2852 ,2854 -->2853 ,
2855 -->2854 ,2856 -->2855 ,2857 -->2856 ,2858 -->2857 ,2859 -->2858 ,
2860 -->2859 ,2861 -->2860 ,2862 -->2861 ,2863 -->2862 ,2864 -->2863 ,
2865 -->2864 ,2866 -->2865 ,2867 -->2866 ,2868 -->2867 ,2869 -->2868 ,
2870 -->2869 ,2871 -->2870 ,2872 -->2871 ,2873 -->2872 ,2874 -->2873 ,
2875 -->2874 ,2876 -->2875 ,2877 -->2876 ,2878 -->2877 ,2879 -->2878 ,
2880 -->2879 ,2881 -->2880 ,2882 -->2881 ,2883 -->2882 ,2884 -->2883 ,
2885 -->2884 ,2886 -->2885 ,2887 -->2886 ,2888 -->2887 ,2889 -->2888 ,
2890 -->2889 ,2891 -->2890 ,2892 -->2891 ,2893 -->2892 ,2894 -->2893 ,
2895 -->2894 ,2896 -->2895 ,2897 -->2896 ,2898 -->2897 ,2899 -->2898 ,
2900 -->2899 ,3121 -->3141 ,3141 -->3121 ,3309 -->3310 ,3310 -->3309 ,
3717 -->3777 ,3718 -->3778 ,3719 -->3779 ,3720 -->3780 ,3737 -->3757 ,
3738 -->3758 ,3739 -->3759 ,3740 -->3760 ,3757 -->3717 ,3758 -->3718 ,
3759 -->3719 ,3760 -->3720 ,3777 -->3737 ,3778 -->3738 ,3779 -->3739 ,
3780 -->3740 ,3781 -->3861 ,3782 -->3781 ,3783 -->3782 ,3784 -->3783 ,
3785 -->3784 ,3786 -->3785 ,3787 -->3786 ,3788 -->3787 ,3789 -->3788 ,
3790 -->3789 ,3791 -->3790 ,3792 -->3791 ,3793 -->3792 ,3794 -->3793 ,
3795 -->3794 ,3796 -->3835 ,3797 -->3836 ,3798 -->3797 ,3799 -->3798 ,
3800 -->3799 ,3801 -->3840 ,3802 -->3801 ,3803 -->3802 ,3804 -->3803 ,
3805 -->3804 ,3806 -->3805 ,3807 -->3806 ,3808 -->3807 ,3809 -->3808 ,
3810 -->3809 ,3811 -->3810 ,3812 -->3811 ,3813 -->3812 ,3814 -->3813 ,
3815 -->3814 ,3816 -->3855 ,3817 -->3856 ,3818 -->3817 ,3819 -->3818 ,
3820 -->3819 ,3821 -->3860 ,3822 -->3821 ,3823 -->3822 ,3824 -->3823 ,
3825 -->3824 ,3826 -->3825 ,3827 -->3826 ,3828 -->3827 ,3829 -->3828 ,
3830 -->3829 ,3831 -->3830 ,3832 -->3831 ,3833 -->3832 ,3834 -->3833 ,
3835 -->3834 ,3836 -->3795 ,3837 -->3796 ,3838 -->3837 ,3839 -->3838 ,
3840 -->3839 ,3841 -->3800 ,3842 -->3841 ,3843 -->3842 ,3844 -->3843 ,
3845 -->3844 ,3846 -->3845 ,3847 -->3846 ,3848 -->3847 ,3849 -->3848 ,
3850 -->3849 ,3851 -->3850 ,3852 -->3851 ,3853 -->3852 ,3854 -->3853 ,
3855 -->3854 ,3856 -->3815 ,3857 -->3816 ,3858 -->3857 ,3859 -->3858 ,
3860 -->3859 ,3861 -->3820 ,4015 -->4055 ,4016 -->4056 ,4017 -->4057 ,
4018 -->4058 ,4055 -->4015 ,4056 -->4016 ,4057 -->4017 ,4058 -->4018 ,
4545 -->4565 ,4546 -->4566 ,4549 -->4569 ,4550 -->4570 ,4565 -->4545 ,
4566 -->4546 ,4569 -->4549 ,4570 -->4550 ,

  For the reference:

 Below I listed BPRS tiles which look suspicious. However it is not a detailed study, there is more problems in the histos I have accumulated.
BPRS status tables need more work, in particular channels with close to 100% cross talk can't be found using single spectra, because they will fine (just belong to another channel)  

 

Identified BPRS hardware problems:

Tiles w/ ADC=0 for all events:

* 3301-4, 3322-4 - all belong to PMB44-pmt1, dead Fee in 2007
   belonging to the same pmt:
     3321 has pedestal only
     3305-8 and 33205-8  have nice MIP peaks, work well

* 2821, 3781 , both at the end of 80-chanel shift in mapping
     neighbours of 2821: 2822,... have nice MIP 
     similar for neighbours of 3781

* 4525, 4526 FOUND! should be readout from cr=2 position 487 & 507, respectively 
 
I suspect all those case we are reading wrong 'positon' from the DAQ file



Pair of consecutive tiles with close 100% cross talk, see Fig 4.
35+6, 555+6, 655+6, 759+60, 1131+2, 1375+6, 1557+8,
2063+4, 2163+4, 2749+50, 3657+8,   
3739 & 3740 copy value of 3738 - similar case but with 3 channels.
4174+5


Hot pixels, fire at random
1514, 1533, 1557,
block: 3621-32, 3635,3641-52 have broken fee, possible mapping problem 
block: 3941-3976 have broken fee


Almost copy-cat total 21 strips in sections of 12+8+1
3021..32, 3041..48, 3052
All have very bread pedestal. 3052 may show MIP peak if its gain is low.

 

Fig 4. Example of pairs of correlated channels.

11 BPRS absolute gains from MIP, ver1.0 ( example of towers)

 BPRS absolute gains from MIP, ver 1.0 

  • INPUT: ~9 days of fmsslow-triggered events, days 62-70, 200 runs, 6M events
  • DATA CORRECTIONS:
    • private  BPRS peds(cap,softID) for every run,
    • private status table, excluded only 7 strips with ADC=0
    • event-by-event capID corruption detection and correction
    • use vertex with min{|Z|}, ignore PPV ranking, to compensate for PPV problem
    • BPRS swaps detected by Rory in 2007 data have been applied 
    • BTOW swaps detected & applied
  • TRACKING:
    • select prim tracks with pr>0.4 GeV, dEdX in [1.5,3.3] keV, |eta|<1.3, zVertex <50 cm
    • require track enters & exits a tower 1cm from the edge
  • triple MIP coincidence, requires the following (restrictive) cuts:
    •  to see BPRS  MIP ADC :  TPC MIP track and in the same BTOW tower  ADC in [10,25] 
    •  to see BTOW MIP ADC :  TPC MIP track and in the same BPRS tile  ADC in [7,30] 

 


Fig 1 Typical MIP signal seen by BPRS(left) & BTOW (right) for soft ID=??, BPM16.2.x  (see attachment 1 for more)

Magenta line is at MIP MPV-1*sigma -> 15% false positives

 


Fig 2 Typical MIP signal seen by BPRS, pmt=BPM16.2

Average gain of this PMT is on the top left plot, MIP is seen in ADC=4.9, sig=2.6


Fig 3 Most desired MIP signal (ADC=16) seen by BPRS(left) & BTOW (right) for soft ID=1388, BPM12.1.8

Magenta line is at MIP MPV-1*sigma -> 15% false positives,  (see attachment 2 for more)

 


Fig 4 Reasonable BPRS, pmt=BPM11.3, pixel to pixel gain variations is small

 


Fig 5 High MIP signal (ADC=28) seen by BPRS(left) & BTOW (right) , BPM11.5.14

Magenta line is at MIP MPV-1*sigma -> 15% false positives,  (see attachment 3 for more)

 


Fig 6 High gain BPRS, pmt=BPM11.5

 

12 MIP gains ver1.0 (all tiles, also BTOW)

 This is still work in progress, same algo as on previous post.

Now I run on  12M events (was 6 M) and do rudimentary QA on MIP spectra, which results with ~10% channel loss (the bottom figure). However, the average MIP response per tile is close to the final value.

Conclusion: only green & light yellow tiles have reasonable MIP response of ~15 ADC. For blue we need to rise HV, for red we can lower it (to reduce after pulsing). White area are masked/dead pixels.


Fig 1: BPRS MIP gains= gauss fit to MIP peak.

A) gains vs. eta & phi to see BPM pattern. B) gains with errors vs. softID, C) sigma MIP shape, D) tiles killed in QA 

 


Fig 2: BTOW MIP gains= gauss fit to MIP peak. Content of this plot may change in next iteration.

A) gains vs. eta & phi. "ideal" MIP is at ADC=18, all towers. Yellow& red have significantly to high HV, light blue & blue have too low HV.

B) gains with errors vs. softID, C) sigma MIP shape, D) towers killed in QA 

 

13 MIP algo, ver=1.1 (example of towers)

This is an illustration of improvement of MIP finding efficiency if ADC gates are set on BPRS & BTOW at the places matched to actual gains instead of  fixed 'ideal' location.


Fig 1 is from previous iteration (item 11) with fixed location  MIP gates. Note low MIP yield in BPRS (red histo) due to mismatched BTOW ADC gate (blue bar below green histo).


 


Fig 2 New iteration with adjusted MIP gates. (marked by blue dashed lines).

MIP ADC gate is defined (based on iteration 1) by mean value of the gauss fit +/- 1 sigma of the gauss width, but not lower than ADC=3.5 and not higher than 2* mean ADC

Note similar MIP yield in BPRS  & BTOW. Also new MIP peak position from Gauss fit did not changed, meaning algo is robust. The 'ideal' MIP ADC range for BTOW is marked by magenta bar (bottom right) - is visibly too low.


 


Attached PDF shows similar plots for 16 towers. Have a look at page 7 & 14

14 ---- MIP gains ver=1.6 , 90% of 4800 tiles ----

 BPRS absolute gains using TPC MIPs & BTOW MIP cut, ver 1.6 , 2008 pp data

  • INPUT:  fmsslow-triggered events, days 43-70, 525 runs, 16M events (see attachment 1)
    • BTOW peds & ped-status  from offline DB
  • DATA CORRECTIONS (not avaliable using official STAR software)
    • discard stale events
    • private  BPRS peds(cap,softID) for every run,
    • private status table
    • event-by-event capID corruption detection and correction
    • use vertex with min{|Z|}, ignore PPV ranking, to compensate for PPV problem
    • BPRS swaps detected by Rory in 2007 data have been applied 
    • additional ~240 BPRS swaps detected & applied
    • BTOW ~50 swaps detected & applied
    • BTOW MIP position determine independently (offline DB gains not used)
  • TRACKING:
    • select prim tracks with pr>0.35 GeV, dEdX in [1.5,3.3] keV, |eta|<1.3, zVertex <60 cm, last point on track Rxy>180cm
    • require track enters & exits a tower 1cm from the edge, except for etaBin=20 - only 0.5cm is required (did not helped)
  • triple MIP coincidence, requires the following (restrictive) cuts:
    •  to see BPRS  MIP ADC :  TPC MIP track and in the same BTOW tower  ADC in  MIP peak +/- 1 sigma , but above 5 ADC 
    •  to see BTOW MIP ADC :  TPC MIP track and in the same BPRS tile   ADC in  MIP peak +/- 1 sigma , but above 3.5 ADC

 


Fig 1.   Example of typical BPRS & BTOW MIP peak determine in this analysis. 

MIP ADC gate (blue vertical lines) is defined (based on iteration 1.0) by the mean value of the gauss fit +/- 1 sigma of the gauss width, but not lower than ADC=3.5 (BPRS) or 5 (BTOW) and not higher than 2* mean ADC.

 FYI, the  nominal MIP ADC range for BTOW (ADC=4096 @ ET=60 GeV/c) is marked by magenta bar (bottom right).

  • Attachment 6 contains 4800 plots  of BPRS & BTOW like this one below ( large 53MB !!)
  • Numerical values of MIP peak position,width, yield  for all 4800 BPRS tiles are in attachment 4.

 


Fig 2.  ADC of MIP peak for 4800 BPRS tiles.

Top plot: mean, X-axis follows eta bin , first West then East. Y-axis follows  |eta| bin, 20 is at physical eta=+/- 1.0.Large white areas are due to bad BPRS MAPMT (4x4 or 2x8 channels), single white rectangles are due to bad BPRS tile or bad BTOW tower.

Middle plot: mean +/- error of mean, X-axis =soft ID. One would wish mean MIP value is above 15 ADC to place MIP cut comfortable above the pedestal (sig=1.5-1.8 ADC counts).

Bottom plot: width of MIP distribution. Shows the width of MIP shape is comparable to the mean and we want to put MIP cut well below the mean to not loose half of discrimination power.

Note, the large # 452 of not calibrated BPRS tiles does not mean that many are broken. There are 14 known bad PMTs and e 'halves' , total=15*16=240 (see attachment 2). There rest are due broken towers (required by MIP coincidence) and isolated broken fibers, FEE channels.



Fig 3. Example of PMT with fully working 16 channels.
Top left plot shows average MIP ADC from 16 pixels. Top middle: correlation between MIP peak ADC and raw slope - can be used for relative gain change in 2009. Top right shows BTOW average MIP response.
Middle: MIP spectra for 16 pixels.
Bottom: raw spectra fro the same 16 pixels.

300 plots like this  is in attachment 3.

 


Fig 4.  Top plot: average over 16 pixels MIP ADC  for 286 BPRS pmts.  X axis = PMB# [1-30] + pmt #[1-5]/10. Error bars represent RMS of distribution (not error of the mean).

Middle plot : ID of 14 not calibrated PMTs. For detailed location of broken PMTs see attachment 2,  the red computer-generated ovals on the top of 2007 Will's scribbles mark broken PMTs (blue ovals are repaired PMTs) found in this 2008 analysis.

Bottom plot shows # of pixels in given PMT  with reasonable MIP signal (used in the top figure).

  • Numerical values of MIP peak per PMT are in attachment 5.


 

 

 


Fig 5.  ADC of MIP peak for 4800 BTOW tower. Top lot: mean, middle plot: mean +/- error of mean, bottom plot: width of MIP 

  •  Numerical values of MIP peak position,width, yield  for all 4800  BTOW towers are in attachment 4.

Note, probably 1/2 of not calibrated BTOW towers are broken, the other half is due to bad BPRS tiles, required to work by this particular algo.

Koniec !!!

 

15 Broken BPRS channels ver=1.6, based on data from March of 2008

 The following BPRS pmts/tiles have been found broken or partially not functioning, based on reco MIP response from pp 2008 data.

 

 Based on PMT-sorted spectra available HERE  (300 pages , 3.6MB)

 

Table 1. Simply dead PMT's. Raw spectra contain 16 nice pedestals, no energy above, see Fig 2.

PMB,pmt, PDF page # , 16 mapped softIDs
2,3     8, 2185 2186 2187 2188 2205 2206 2207 2208 2225 2226 2227 2228 2245 2246 2247 2248 
2,4,    9, 2189 2190 2191 2192 2209 2210 2211 2212 2229 2230 2231 2232 2249 2250 2251 2252 
4,5,   20, 2033 2034 2035 2036 2053 2054 2055 2056 2073 2074 2075 2076 2093 2094 2095 2096 
5,1,   21, 1957 1958 1959 1960 1977 1978 1979 1980 1997 1998 1999 2000 2017 2018 2019 2020 
12,2,  57, 1421 1422 1423 1424 1425 1426 1427 1428 1441 1442 1443 1444 1445 1446 1447 1448 
14,1,  66, 1221 1222 1223 1224 1225 1226 1227 1228 1241 1242 1243 1244 1245 1246 1247 1248 
24,4, 119, 433 434 435 436 453 454 455 456 473 474 475 476 493 494 495 496 
25,4, 124, 353 354 355 356 373 374 375 376 393 394 395 396 413 414 415 416 
26,4, 129, 269 270 271 272 289 290 291 292 309 310 311 312 329 330 331 332 
32,3, 158, 2409 2410 2411 2412 4749 4750 4751 4752 4769 4770 4771 4772 4789 4790 4791 4792 
44,5, 220, 3317 3318 3319 3320 3337 3338 3339 3340 3357 3358 3359 3360 3377 3378 3379 3380 
39,2, 192, 2905 2906 2907 2908 2925 2926 2927 2928 2945 2946 2947 2948 2965 2966 2967 2968    

 

Table 2.  FEE is broken (or 8-connector has a black tape), disabling 1/2 of PMT, see Fig 3.

PMB,pmt,  nUsedPix,  avrMIP (adc), rmsMIP (adc),PDF page # , all mapped softIDs
7,1,   7,   19.14, 4.36,  31, 1797 1798 1799 1800 1817 1818 1819 1820 1837 1838 1839 1840 1857 1858 1859 1860   
40,1,  8,    5.16, 0.53, 196, 2981 2982 2983 2984 3001 3002 3003 3004 3021 3022 3023 3024 3041 3042 3043 3044  
40,2,  6,    5.44, 0.80, 197, 2985 2986 2987 2988 3005 3006 3007 3008 3025 3026 3027 3028 3045 3046 3047 3048  
40,3, 12,    8.50, 1.05, 198, 2989 2990 2991 2992 3009 3010 3011 3012 3029 3030 3031 3032 3049 3050 3051 3052    
44,1, 10,   13.72, 8.24, 216, 3301 3302 3303 3304 3305 3306 3307 3308 3321 3322 3323 3324 3325 3326 3327 3328  
45,2,  8,    5.04, 1.55, 222, 3421 3422 3423 3424 3425 3426 3427 3428 3441 3442 3443 3444 3445 3446 3447 3448   
51,5,  7,   11.37, 2.15, 255, 3877 3878 3879 3880 3897 3898 3899 3900 3917 3918 3919 3920 3937 3938 3939 3940  
52,5,  8,   15.84, 4.80, 260, 3957 3958 3959 3960 3977 3978 3979 3980 3997 3998 3999 4000 4017 4018 4019 4020  
60,1,  8,   15.12, 3.41, 296, 4581 4582 4583 4584 4601 4602 4603 4604 4621 4622 4623 4624 4641 4642 4643 4644

 

Table 3. Very low yield of MIPs (1/5 of typical), may de due to badly sitting optical connector, see Fig 4

PMB,pmt, QAflag, nUsedPix,  avrMIP (adc), rmsMIP (adc),PDF page # , all mapped softIDs
10,5,  14,     0,  0.00, 0.00,  50, 1553 1554 1555 1556 1573 1574 1575 1576 1593 1594 1595 1596 1613 1614 1615 1616    
31,5,  14,     0,  0.00, 0.00, 155, 4677 4678 4679 4680 4697 4698 4699 4700 4717 4718 4719 4720 4737 4738 4739 4740  
37,2,   0,    10, 12.90, 7.41, 182, 2745 2746 2747 2748 2765 2766 2767 2768 2785 2786 2787 2788 2805 2806 2807 2808    
49,1,   0,    16,  9.36, 3.55, 241, 3701 3702 3703 3704 3705 3706 3707 3708 3721 3722 3723 3724 3725 3726 3727 3728   

 

Table 4. Stuck LSB in FEE, we can live with this. (do NOT mask those tiles)

PMB,pmt, QAflag, nUsedPix,  avrMIP (adc), rmsMIP (adc),PDF page # , all mapped softIDs
51,1,0, 15,   8.37, 1.30, 251, 3861 3862 3863 3864 3881 3882 3883 3884 3901 3902 3903 3904 3921 3922 3923 3924  
51,2,0, 16,   8.66, 1.06, 252, 3865 3866 3867 3868 3885 3886 3887 3888 3905 3906 3907 3908 3925 3926 3927 3928  
51,3,0, 16,  11.08, 1.28, 253, 3869 3870 3871 3872 3889 3890 3891 3892 3909 3910 3911 3912 3929 3930 3931 3932  
51,4,0, 16,  17.16, 2.70, 254, 3873 3874 3875 3876 3893 3894 3895 3896 3913 3914 3915 3916 3933 3934 3935 3936   

Table 5. Other problems:

PMB,pmt, QAflag, nUsedPix,  avrMIP (adc), rmsMIP (adc),PDF page # , all mapped softIDs
31,2,0, 16,  12.32, 3.73, 152,4665 4666 4667 4668 4685 4686 4687 4688 4705 4706 4707 4708 4725 4726 4727 4728   

 


Fig 1. Example of fully functioning PMT (BPM=4, pmt=5). 16 softID are listed at the bottom o fthe X-axis.
Top plot: ADC spectra after MIP condition is imposed based on TPC track & BTOW response.
Bottom plot: raw ADC spectra for the same channels.

 


Fig 2. Example of dead PMT with functioning FEE.  


Fig 3. Example of half-dead PMT, comes in pack, most likely broken FEE.  


Fig 4. Example of weak raw ADC, perhaps optical connector got loose.  


Fig 5. Example of stuck LSB, We can live with this, but gain hardware must be ~10% higher (ADC--> 18)  

16 correlation of MIP ADC vs. raw slopes

 Scott asked for crate based comparison of MIP peak position vs. raw slopes .

I selected 100 consecutive BPRS tiles, in 2 groups, from each of the 4 crates. The crate with systematic lower gain is the 4th (PSD-20E). 

The same spectra from pp 2008 fmsslow events are used as for all items in the Drupal page.

 


Fig 1. BPRS carte=PSD-1W

 


Fig 2. BPRS carte=PSD-19W

 


Fig 3. BPRS carte=PSD-1E

 


Fig 4. BPRS carte=PSD-20E This one has lower MIP peak