SciFi Tracker Test Beam November 2015

Instructions for shifters!

Aim of the test beam

Fibre Mats/Modules



Linear table and mechanics

Position definition

Measurement plan

Beam setting for Nov 2015:

SciFi Tracker Test Beam May 2015

Contact: Mark Tobin (GSM: 161858)


Images courtesy of R. Ekelhof and J. Müller

Full size files can be found in the CERNBOX folder:

Google photo album link (lower resolution, temporary until the CERNBOX upgrade):

Instructions for shifters!

Shift list

The shift list can be found here.

Aim of the test beam

  • Hit efficiency and spatial resolution as function of:
    1. y for 3 points along the fibres (A = mirror, B = 1m from mirror, C = 2m from mirror)
    2. x (for gaps between SiPMs)
    3. angle
  • Read-out with 8-channel-PACIFIC-prototype (if possible)

Fibre Mats/Modules

  • 2.5 m 6-layer coverlay mat from CERN (used in 2014 test beam). (CERN4)
  • Two 2.5 m 5-layer mat, 2010 fibres, casted and mounted between panels (HD2 used in 2014 test beam). (HD1 & HD2)
  • DUT: 2.5 m 6-layer mat, 2015 fibres, casted and mounted between panels (NEW) (SLAYER3)
  • Latest generation Hamamatsu SiPMs on all modules.
Module SiPM (lower) (SiPM upper) LED bar LED Driver Uplink (lower1) Uplink (lower2) Uplink (upper1) Uplink (upper2)
HD2 30 28 3 3 5 (000-063) 5 (064-127) 6 (000-063) 6 (064-127)
HD1 H07 H03 1 1 7 (000-063) 7 (064-127) 8 (000-063) 8 (064-127)
CERN4 H02 H01 4 4 1 (127-064) 1 (063-000) 2 (127-064) 2 (063-000)
SLAYER3 (DUT) 33 35 5 2 3 (000-063) 3 (064-127) 4 (000-063) 4 (064-127)


  • Read out 4 modules modules with two SiPMs simultaneously. Arrays are centered on the inner 7cm.
  • 8 SPIROC cards (4 from HD, 6 from AC).
  • One USB board (available).


  1. 3 AMS silicon ladders, scintillator trigger, outer veto (2cm x 2cm hole)
    There is a comprehensive description of the proposed set up available in Roman Greim's presentation at the test beam kick-off meeting .
  2. Timepix3

Linear table and mechanics

  1. DESY table for Aachen telescope
    Allows for vertical and horizontal displacement by +/- 0.5 m. Motorised and remote-controlled.
  2. New translation table for modules from EPFL
    Allows horizontal and vertical translations of 2.5 m and 0.8 m, respectively. ~1cm steps are possible in vertical and horizontal.

Position definition

Horizontal positions (in table coordinates, module is 2424mm long):

A: 225.5cm (beam is near mirror) B: 125.5cm C: 30.5cm (beam is near SiPMs)

Vertical position:

Default Y-Table Position: 72.4cm

Measurement plan

Hit Efficiency/Resolution

at the following points (600k with VeLo, overnight only)

1) Do position A and C first, at 0°, 10°, 20°, 30°!!!! 2) Continue with angles in between 3) Position B is last (same order concerning the angles)

  -30° -25° -20° -15° -10° -5° 10° 15° 20° 25° 30°
  towards VELO (no VELO sync)   towards AMS
A             done done done   done done done
B     done   done   nearly done         done  
C             done done done   done done done

Attenuation Length Scan

(150k during morning/afternoon shifts)

  30.5 35.5 45.5 55.5 65.5 75.5 85.5 95.5 105.5 115.5 125.5 135.5 145.5 155.5 165.5 175.5 185.5 195.5 205.5 215.5 225.5
done done done done done done done done done done done done done done done done done done done done done
Vertical Scan

Position A (150k during morning/afternoon shifts)

Absolute height 10° 20°
68cm done done (2x) done
69cm done done (2x) done
70cm done done (2x) done
71cm done done (2x) done (2x)
72cm done done (2x) done
73cm done done (2x) done

Position B (150k during morning/afternoon shifts)

Absolute height
68cm done
69cm done
70cm done
71cm done
72cm done
73cm done

Position C (150k during morning/afternoon shifts)

Absolute height 10°
68cm done(2x) done
69cm done done
70cm done done
71cm done done
72cm done (2x) done
73cm done (2x) done
Overvoltage Scan

(150k during morning/afternoon shifts)

  +1.5 +2.0 +2.5 +3.0 +4.0 +4.5 +5.0
A done done done done done done done
C done done done done done done done
fine Overvoltage Scan

(50k during morning/afternoon shifts)

  +3.3 +3.4 +3.5 +3.6 +3.7
A done 3x done 3x done 3x done 3x done 3x
Gap Scan

(600K during morning/sfternoon shifts) For different angle, we need to search for a proper height, so the beam can cover the gap position (uplink4 slayer3Upper) first do point A + C, if more time get point B

  10° 20°
A 68.75cm (done) 69.5 (done) 70.3cm (done)
B     70.3cm (90k)
C 68.75cm (almost done) 68.8 (done) 70.3cm (done)

Analysis and Software

Some of the analysis software is in a git repository. Ask Roman Greim for access. Max Neuner has also developed analysis software based on ntuples.

Data Set Analysis Person Link to Results
Hit Eff./ Resolution ABC@ 0° Max Neuner Link 1
Hit Eff./ Resolution AC@ 5° - -
Hit Eff./ Resolution ABC@ 10° Dominik Mitzel -
Hit Eff./ Resolution AC@ 15° - -
Hit Eff./ Resolution ABC@ 20° - -
Hit Eff./ Resolution ABC@ 25° - -
Hit Eff./ Resolution AC@ 30° - -
Attenuation Length Scan Ana Barbara Link 1
Vertical Scan ABC@ 0° - -
Vertical Scan AC@ 10° - -
Vertical Scan A@ 20° - -
Over-voltage Scan Axel Kuonen -
Gap Scan (other array) AC@ 0° - -
Gap Scan (other array)AC@ 10° - -
Gap Scan (other array)ABC@ 20° - -
Data structure: The data is saved in root-files that are read out with Roman's software. It needs Qt and the class definition in which the data is daved. The data files have also been converted into flat ntuples without any structure where the TTree just contains the leaves for all channels of all Scifi uplinks. These files have the same name as the original file but with the ending ***ntuple.root. They have also been backed up to EOS. A simple script that only needs root, C++11 and the boost library is called "cluster_analysis". It is also in a git repository that Max can give you access.

Instructions for installing the software are available here.

-- MarkTobin - 2015-04-20

Backing up the data to EOS

More information on EOS can be found on and

XROOTD must be installed on a local machine with OPENSSL and KERBEROS5 to move it there from EOS.

1. Copy the files from the server to the client machine (to /data/testbeam_data/).

2. Open a terminal on the "scifionline" client machine. In the /data/testbeam_data directory on the client where the files have been copied:

$ ls *.root > filelist.txt
$ xrootd -c xrootconfig.cfg # this starts the xroot server daemon. ctrl-c after to close it or add & to put in background.

3. Open a terminal on

$ eos ls -l /eos/lhcb/testbeam/scifi/May2015                    #lhcb-scifi-tracker-testbeam has write permission, lhcb has read
$ xrdcp root:// filelist.txt

4. On lxplus, create the following bash script '':

while read -r line
    xrdcp root://$name root://$name
    echo "copying $name to root://"
done < "$filename" 

5. Then run it there:

$ chmod a+x
$ ./ filelist.txt # it will not transfer or overwrite pre-existing files
$ eos ls -l /eos/lhcb/testbeam/scifi

If you want to download a selection of the files you can run the command:

eos ls -A1 /eos/lhcb/testbeam/scifi | grep datarun_ntuple | while read filename; do  xrdcp "root://$filename" .; done

where the word behind the "grep" indicates which files are copied. In this case every file that contains datarun_ntuple in its name.

Beam setting for May 2015:

Scintillator counter: 1E05 (about 1000-1500 triggers per spill) Beam spot: 3.3mm(square) x 14mm (FWHM)

  • beam setting for scifi 2015:

  • collimator settings for scifi 2015 Setting I:
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng CESAR_GUI_0.32.0_25-May-15_09-01-20.png r1 manage 60.5 K 2015-05-25 - 09:33 BlakeLeverington collimator settings for scifi 2015 Setting I
PNGpng CESAR_GUI_0.32.0_25-May-15_09-03-35.png r1 manage 60.1 K 2015-05-25 - 09:32 BlakeLeverington beam setting for scifi 2015
Unknown file formatext HOWTO_2015 r3 r2 r1 manage 6.4 K 2015-05-20 - 23:01 OlivierGoranGirard  
JPEGjpg IMG-20150520-WA0004.jpg r1 manage 362.1 K 2015-05-25 - 13:34 BlakeLeverington  
JPEGjpg IMG-20150520-WA0005.jpg r1 manage 212.6 K 2015-05-25 - 13:34 BlakeLeverington  
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Topic revision: r58 - 2015-11-02 - BlakeLeverington
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