-- MarkWard - 27 Sep 2017

Previous Logbook

01-11-2017

  • Prepared the lab for arrival of HPTPC, Involved taking apart DMTPC and making space for requipment.
  • Latter part of last week was a bit of a disaster having to make two trips to London to see the immigration lawyer
  • Got the vessel into the building! YAY, everyone knows what happened... it was an adventure.
  • CLEANING! lots and lots of cleaning, the vessel was extremely dirty on the inside (and outside)
  • Put curtains back on clean tent (required cleaning also)
  • re-plummbed the hydrolic lines on the vessel, had to tighten a few other fitting
  • Made inventory list of parts we recieved from Cryovac
  • Notes
    • All gas regulators have TIPOC inlet fittings, we will have to change this for relivent DIN/CGA fittings for use in the lab
    • Captured o-ring kf fittings are good for 10bar, note, we appear to have no spares!
    • Vacuum valve... if that is rated to 5 bar id be surprised. Looks like some random valve they found somewhere in the bushes. Part number is SA0150MVQF, technically rated between atmosphere and Vacuum
    • Chamber has 3 missing caps - they are plastic caps that have been taped on. All are KF40s, I think these were the ones used to pressure test with the HV feedthroughs.
    • We will probably want to put a steel brush pipe cleaner through the water drain and air release valves (top and bottom penetrations on the vessel) Both show corrossion and are generally hard to clean.

25-10-2017

  • Lots of meetings with Sam / Cryovac, good news is that the vessel should 'should' be here today, keep fingers crossed.
    • We aquired quotes from kingsbury for cranage in preparation for our own shipping options
    • Speciality Spanish Transport, quote was lowered and we accepted
    • Southern Cranes and Access gave an insane quote, I think this was in response to bad communications between SST and cryovac and themselves which basically involved SST demanding a quote without giving them any information about the Job. So... knowing or believing they had no options, they quoted 1500 ish... which Cryovac (as much as they are not in a position to complain really) identified as crazy.
    • We provided Cryovac with our quote from Kingsbury
    • Cryovac contracted Kingsbury
  • Got my simple diagnoistic tool working on m3daq
    • I made a sym link into /home/dmatter/bin (i think, i cant check, m3daq is offline for the delivery)
    • This means the program can be used from any command line location
    • Invoked by rawAna.exe - if given with no options it will print the usage directions and flags
    • For looking quickly at a root file and rumping the number of events/triggers point rawAna.exe at a raw root file with no arguments
    • -d dumps waveforms to screen ->really fast, much better than using a CINT macro
    • -c dumps CCD images
    • -d -c dumps both to screen
    • It can be used for offline analysis, currently it will do baseline cuts, peak time cuts, find peakheights for the charge channels and output 4 histograms. baseline sigma cut and time cut can be added using appropriate flags (see useage)
  • Wrote small script for exporting fits file using the DMTPC image library for Kulveer to use
  • Lab cleanup, tidy with the team, My task was mostly disconnecting and tidying away all cables and moving the DAQ computer and electronics rack.
  • Shoring props are in place, clean tent has not fallen over... yet

18-10-2017

  • Practiced some mesh stretching, (mostly a helper with Zack and the team)
    • Lots of intersting things learnt
  • Started writing a tool for doing quick diagnostics on data files from DMTPC,
    • Very very fast at dumping waveforms to screen, which is initially the most useful use of it, to check what triggers look like
    • Optionally can dump CCD images along side the waveforms. So we can visually pair up waveforms and Events
    • Slowly updating it to perform baseline cuts given a list of files and generally have it do all of what we usually do in Macros
    • Motivation... CINT IS BAD AND SLOOOOW
    • Already this code appears much faster
  • TPC rail mount designs -> Not got a full assembly drawing yet, though have had a few communications with machine ship, the rails are advancing and hopefully should be out soon.
  • Reviewing Drawings with Zack.
  • Chamber Shipping Drama... mostly Zack doing the waving of sticks at Sam, Adriana speaking to various spanish transport companies.
  • I have spoken to the company wh lifted the DMTPC vessel, they are coming tomorrow to scope the area and will quote us for a UK lift.
  • c7eb6fc7c3dd4bdfc5dcd3f6c97209da.gif

11-10-2017

  • Wrote a "How too and getting started page" for people to use to do basic dmtpc anaylsis etc it is located here
  • Took data sample for purpose of CR-112 calibration, See Adriana's analysis
  • Discovered Trigger issues with the DAQ
    • Appears to ignore trigger and pulse polarity settings (at least for the charge sensitive pre-amp)
    • Settings in the hptpc_neutron template (copied from one of the ones that shipped with the setup) has triggers on charge channels effectively disabled.
    • Thus it appears we are triggering only when we have a signal on the fast amplifers, ONLY negative going
    • Need to investigate this, possibility of hard coding or bug in the DAQ initialisation.
  • Helped (Tiny bit) with the Ring Turning -> See Zacks page
  • Helped (Tiny Tiny bit) with putting clean tent curtains up
  • Created a 50ohm terminator for SHV connectors for grounding the anodes
  • Grounded All anodes and ground meshes
  • Ramped voltage - breakdown reoccurs at same voltages (630-650v)
  • Cycled the gas, first pumping down to ~3x10^-6 mbar and then back to 40mbar
  • Channels now ramp to 670 without sparking, sparking comes in closer to 680V now
  • Cathode performance is identical, sparking occurs at 3200V
  • Slowly ramped up all channels to 680V, sparking is moderate, though approximately 0.1Hz so we can get a few events between sparks
  • Need to write some error handling into my code, currently segfaults if the first event has no triggers... Thus if the first event is after a spark, it sometimes contains zero triggers.
  • Going to migrate to Linappserv and make a set of compiled programs to improve analysis speed
  • Have 3 data samples in different configurations for analysis

04-10-2017

  • Worked with Adriana on developing the analysis to accept multiple raw files
  • Can identify each peak in the spectrum based upon behavour of the CSP channel.
  • PeakHeights.png
  • hptpc_neutron00_000_018.pnghptpc_neutron00_020_078.png
  • hptpc_neutron00_047_024.png
  • All this is within a single run, a spark appears to trigger the change between each state. Looking through later files, the behavour returns to normal and then back to bad again
  • Applying peak time cut effectively removes this bad behavour from the files.
  • See Adriana's logbook for final plot showing combined files with baseline and time peak time cuts (Also preliminary gain)
  • Shakedown of Amplifiers was good, using the test input, scope traces looked identical for all channels.
  • 3 instances of bad grounding on the boards which has now been fixed. Extra insulation on the inside of the cases has been added.
  • Vessel backfilled with CF4 to 40mbar(30 torr), pressure reached before backfill was 8.44x10^-7 mbar
  • Drift field achieved and stable 3200V (compared to 2700V previously) Getting better smile can at do 100V/cm field at least.
  • Anode voltage frown Bottom left starts to spark at approx 0.5-1Hz when at a voltage of 650V, 50V short of where I usually try and take data to see how everything is behaving.
  • All_Alphas.png

27-09-2017

  • Baseline Analysis,
    • Initially performed my own baseline extraction in order to learn a few things about the raw TFile structure
    • Rewrote the same analysis in the space of a few hours using the dmtpc framework
  • Process is to,
    • Extract the baseline from every trace and push it into a histogram for each channel
    • Fit gaussian/find RMT and define a cut of accepting only waveforms that have a baseline within 8sigma
    • Remove whole events that do not make the cut, Replot and refit.
  • BaseLines_bfandaf.png
  • Pulse height analysis
    • dmtpc framework is mostly defined in Pulse.hh (for anyone who is interested)
    • The getPeak() function extracts the peak and subtracts for baseline offset
    • Further acceptance can be performed based on getPeakTime()
    • Code (and a tutorial on what each part of my macro is doing what has been passed down to Adriana for further modification/development (getPeakTime() cuts which shouldn't take much development
    • Currently my analysis works only one a single file though it should be realitively simple to make it work on a string of files.
    • Quite slow... might concider a compiled version rather than a macro, shakes fist at CINT
  • PeakHeights.png
  • PeakHeights_Cut.png
  • Friday - Adriana and I did a full vacuum system and DMTPC operations tutorial,
    • Made modification to HV feedthrough, changing the connection type to a push on one
    • Applied Kapton insulation over any bare wire, the push on connector and length of the pin.
    • Proved the HV feedthrough operates up to the full capacity of the supply (8kV) in Nitrogen, no sparks or issues
    • Evacuuated vessel
  • Started Testing performance of the Cremat boards, Initially tests look like boards are healthy, but we have devised a full set of tests to be performed in order to check board health and operation of different Amps in each
  • Should be completed in next couple of days, if all checks are good we move onto the grounding and backfill the detector for sample runs

Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng All_Alphas.png r1 manage 810.8 K 04 Oct 2017 - 13:07 MarkWard  
PNGpng BaseLines_bfandaf.png r1 manage 94.9 K 27 Sep 2017 - 12:39 MarkWard  
PNGpng PeakHeights.png r1 manage 36.8 K 27 Sep 2017 - 12:39 MarkWard  
PNGpng PeakHeights_Cut.png r1 manage 15.7 K 27 Sep 2017 - 12:49 MarkWard  
GIFgif c7eb6fc7c3dd4bdfc5dcd3f6c97209da.gif r1 manage 376.9 K 18 Oct 2017 - 13:31 MarkWard  
PNGpng hptpc_neutron00_000_018.png r1 manage 185.2 K 04 Oct 2017 - 10:39 MarkWard  
PNGpng hptpc_neutron00_020_078.png r1 manage 186.8 K 04 Oct 2017 - 10:39 MarkWard  
PNGpng hptpc_neutron00_047_024.png r1 manage 187.8 K 04 Oct 2017 - 10:39 MarkWard  

This topic: Public > UserList > MarkWard > MWardWorkDiary2017Log1
Topic revision: r9 - 01 Nov 2017 - MarkWard
 
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