VELO Online Monitoring Wish List

This page is meant to be a scratch area for collecting ideas what to monitor and how. So everybody should feel free to add some ideas! As a starting point I have added a few items collected from various sources.

-- Kurt Rinnert - 13 Mar 2008

Data retrieved from PVSS

In this section we collect quantities we want to monitor that can be directly retrieved from PVSS.

Detailed Specifcations

None yet.


Available measure quantities from hardware
  • Si current
  • Beetle currents
  • Temperature of hybrid
  • Rack temperatures
  • Temperature of RF foil
  • Beam currents

Correlations of some of these
  • Si current vs temp.
  • Beetle current and Si current superimposed
  • Current vs foil temp.

Radiation monitoring
  • Measure Si current
  • BCM
  • 2 beam currents

Power supply values
  • Current and past history

BEETLE values
  • Number of resets per Tell 1.
  • Pipeline synchronisation errors.

TELL1 values
  • Need to know how often the NZS bank is read out (approx once/s).
  • Need to decide on list of variables to monitor.
  • Want to track pedestal values.
  • RMS of common mode.

Data derived from analysis jobs

In this section we collect quantities we want to monitor that are derived from analysis jobs. More specifically everything that is based on results of a Gaudi job running on the the online farm. There are two sub-categories: slow monitoring with history and fast monitoring without history. We expect the slow monitoring to be updated with ~0.01 Hz and the fast monitoring with ~2 Hz. For the fast monitoring/visualization it is forseen to run a dedicated job on a dedicated node, circumventing the client/server architecture that is used for the standard, low frequency, monitoring.

Low frequency monitoring

Detailed Specifications

Higher level quantities
  • residuals (preferably for small angle tracks with many spacepoints)
    • vs r/phi for alignment
      • for each sensor make unbiased straight line track fit and compute intercept with sensor
      • calculate residual (DeVeloSensor)
      • for R sensor: plot residual vs phi (calculating phi from track state)
      • for Phi sensor: plot residual vs r (calculating r from track state) and vs phi (phi of strip at minimum strip radius +/- stereo angle)
      • update frequency: order of 10 seconds
      • when histogram has about 10'000 entries at least 1 minute old) create a ProfileX() (root method)
      • this profile should be kept, update can be ensured to be >=1min
      • fit profile with sin+cos+const
      • (all code available from software alignment)


Quantities derived from NZS Data
  • noise before/after common mode
  • pedestals
  • ADC vs strip/chip channel
  • correlation plots between adjacent sensors
  • S/N per sensor (split into regions)
  • time development of pedestals
  • time development of noise

Quantities derived from ZS data
  • hitmaps
  • sensor efficiency
  • sensor occupancy
  • number of clusters vs strip number

Higher level quantities
  • tracks (this is very generic, needs to be fleshed out, like e.g. below)
  • residuals (preferably for small angle tracks with many spacepoints)
    • vs r/phi for alignment
    • vs beetle readout direction for R sensor x-talk
    • vs pitch and angle for resolution
    • (more or less all of this code already available in sensor alignment software)
  • Alignment monitoring through alignment constants
    • residuals insensitive to less well constrained DOFs
    • rerun alignment algorithms and monitor change in parameters

High frequency visualization

Detailed Specifications

None yet.


  • beam position
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Topic revision: r4 - 2008-03-31 - MarcoGersabeck
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