STAR Offline QA Shift Histogram Description

This document lists the QA histograms for the Offline QA Shifts for the Year 2001 data run. The present set of plots are from the MDC4 year 2001 simulation runs. In comparing the following page numbers and plots to what you have in the actual QA postscript files for your specific QA job you will notice that things do not match page-by-page. The actual set of QA histograms generated during reconstruction depends on the set of Makers which are active in the chain. However, all plots in the EventQA_shiftLM, MM, and HM files should be described here, just not in the same sequence.

A postscript version of the MDC4 QA Shift histograms is available here. Select the file EvQA_shift.ps.

Lanny Ray, The University of Texas at Austin
June 6, 2001

Page Index for QA Shift Plots

  • Page 1
  • Page 2
  • Page 3
  • Page 4
  • Page 5
  • Page 6
  • Page 7
  • Page 8
  • Page 9
  • Page 10
  • Page 11
  • Page 12
  • Page 13
  • Page 14
  • Page 15
  • Page 16
  • Page 17
  • Page 18
  • Page 19

  • Page 1

  • Distribution of truncated mean dE/dx for TPC outer (solid line) and inner (dashed line) sectors. The outer sector values should be larger than the inner sector due to the difference in pad lengths. The distributions should have similar Landau shapes. Peak position is nominally at ~0.015E-04 but could vary depending on calibrations.

    Primary vertex finding status for run; events with (1) and without (-1) final vertex. The relative fraction of events with primary vertex depends on trigger, beam diamond width and position.

    Ratio of total charge in all reconstructed clusters in TPC east to west halves. Should be peaked at ~1 with FWHM ~ 0.5.

    Ratio of total charge in all reconstructed clusters in FTPC East to West. Should be peaked at ~1.

    Distribution of number of reconstructed space points in TPC. Should scale with centrality, depends on multiplicity cut for this set of plots (i.e. low, medium or high).

    Distribution of number of reconstructed space points in SVT. Should scale with centrality, depends on multiplicity cut for this set of plots (i.e. low, medium or high). Also depends strongly on vertex position distribution.

  • Page 2

  • Distribution of number of reconstructed space points in FTPC East (solid line) and West (dashed line). Should have similar means and widths; scales with centrality, depends on multiplicity cut for this set of plots (i.e. low, medium or high).

    Distribution of reconstructed space points in TPC with respect to z-coordinate. Should be flat within statistics. Watch out for anamolous peaks at z=0 (central membrane), steps or unusual spikes or dips. Some roll-off at the ends is normal.

    Distribution of reconstructed space points in TPC with respect to azimuthal coordinate (phi) for east (solid line) and west (dashed line) halves. Should be flat except for the 12-fold sector structure.

    Distribution of reconstructed space points in TPC with respect to padrow number 1-45. Should display gradual fall-off; watch for anamolous spikes and dips.

    Distribution of reconstructed space points in SVT with respect to z-coordinate. Should be flat within statistics with step like drop off at larger abs(z) due to SVT layers. Depends on distribution of collision vertices.

    Distribution of reconstructed space points in SVT with respect to azimuthal coordinate (phi). Should be flat within statistics.

  • Page 3

  • Distribution of reconstructed space points in SVT with respect to layer number 1-3. Should have larger number in outer 2 layers than the first.

    Distribution of reconstructed space points assigned to tracks in FTPC East (solid line) and West (dashed line) with respect to padrow number. The horizontal axis shows padrow numbers where FTPC-West is 1-10 and FTPC-East is 11-20. Pads #1 and #11 are closest to the center of STAR. These should be similar in shape and magnitude and should peak near the middle of each detector.

    Distribution of hit multiplicity in the RICH detector.

    Distribution of number of hits per reconstructed energy cluster in the EMC-barrel.

    Distribution of energy in reconstructed clusters in EMC barrel.

    Pseudorapidity distribution of reconstructed energy clusters in the EMC-barrel patch.

  • Page 4

  • Azimuthal distribution of reconstructed energy clusters in the EMC-barrel patch.

    Distribution of number of hits per reconstructed energy cluster in the SMD pseudorapidity (eta) dependent wire patch.

    Pseudorapidity distribution of reconstructed energy clusters in the SMD pseudorapidity (eta) dependent wire patch.

    Distribution of number of hits per reconstructed energy cluster in the SMD azimuthal angle (phi) dependent wire patch.

    Azimuthal distribution of reconstructed energy clusters in the SMD azimuthal angle (phi) dependent wire patch.

    Energy distribution for EMC-SMD Category 4 clusters. These correspond to matched clusters for the EMC barrel, SMD-eta and SMD-phi.

  • Page 5

  • Pseudorapidity distribution of Category 4 EMC-SMD clusters.

    Azimuthal distribution (in radians) of Category 4 EMC-SMD clusters.

    Distribution of widths (sigma) of Category 4 EMC-SMD clusters with respect to pseudorapidity.

    Distribution of widths (sigma) of Category 4 EMC-SMD clusters with respect to azimuthal angle.

    Differences between centroids of Category 4 EMC-SMD clusters and projected positions of TPC tracks at EMC with respect to pseudorapidity. Should be peaked at ~0.

    Differences between centroids of Category 4 EMC-SMD clusters and projected positions of TPC tracks at EMC with respect to azimuthal angle. Should be peaked at ~0.

  • Page 6

  • Multiplicity distribution of Category 4 EMC-SMD clusters. Should scale with centrality, depends on multiplicity cut for this set of plots (i.e. low, medium or high).

    Distribution of momenta of global tracks matched to Category 4 EMC-SMD clusters.

    Distribution of EMC and SMD cluster types by Category number.

    Quality flag values for all global tracks. Some with large, negative values may not appear on plot; check stat. box for underflows. Majority of tracks should have iflag>0, corresponding to good, usable tracks. Refer to: dst_track_flags.html and kalerr.html for description of flag values.

    Ratio of good global tracks to total for tracks with TPC hits only, dashed line. Same for global tracks with both SVT and TPC hits, solid line. Both distributions should be a little less than 1, with the SVT+TPC tracks being slightly better.

    Global track multiplicity distribution for TPC-only and SVT+TPC tracks. Magnitude and width depends on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

  • Page 7

  • Scatter plot of good global track multiplicities in FTPC West versus FTPC East. Distribution should be correlated and lie along the reference diagonal line. Magnitudes and widths depend on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Global track detector IDs for good tracks. Refer to: /afs/rhic/star/packages/DEV00/pams/global/inc/StDetectorDefinitions.h for Detector ID codes.

    Coarse scale distribution along the z-axis (from -200 to +200 cm) of the DCA points to the nominal beam line (z-axis, x=y=0) for all TPC and SVT+TPC global tracks. Peaks indicate probable locations of individual collision vertices. There should be many peaks corresponding to the RHIC beam-beam collision region.

    Fine scale distribution along the z-axis (from -50 to +50 cm) of the DCA points to the nominal beam line (z-axis, x=y=0) for all TPC and SVT+TPC global tracks. Peaks indicate probable locations of individual collision vertices. Peaks near the center should be narrower than those beyond about 25 cm due to variations in the effective radiation thickness of the SVT assembly along the z-axis.

    Scatter plot of the tangent of the dip angle (tanl) versus the z-coordinate (from -25 to 25 cm) of the DCA points to the nominal beam line (z-axis, x=y=0) for all TPC and SVT+TPC global tracks. Vertical bands should be seen corresponding to individual events. The bands should be smooth and continuous; breaks at tanl=0 indicate probable TPC calibration errors in either the t0 offset or the drift speed. This is best seen for high multiplicity events.

    Scatter plot of the z-coordinate of the first fitted hit in the TPC versus the z-coordinate (from -25 to 25 cm) of the DCA points to the nominal beam line (z-axis, x=y=0) for all TPC-only global tracks and SVT+TPC global tracks in which the first point used in the fit lies in the TPC (i.e. SVT assigned hits are thrown out during the fitting process). Vertical bands should be seen corresponding to individual events. The bands should be smooth and continuous; breaks at z=0 indicate TPC calibration errors in either the t0 offset or the drift speed. This is best seen for high multiplicity events. This plot is of limited value compared to the previous due to the SVT which catches most of the first hits.

  • Page 8

  • Scatter plot of the azimuthal direction angle (psi) versus the z-coordinate (from -25 to 25 cm) of the DCA points to the nominal beam line (z-axis, x=y=0) for all TPC and SVT+TPC global tracks. Vertical bands should be seen corresponding to individual events. The bands should be smooth, straight and continuous indicating azimuthal symmetry in the tracking. Bends or offsets could indicate problems in individual TPC sectors such as voltage sags or drifts. These are best studied with high multiplicity events.

    Ratio of number of fitted points to total points on track for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Should peak at ~1.

    Ratio of number of fitted points to estimated maximum number for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Peak at low value indicates track splitting. Ratio for SVT+TPC global tracks should peak near 1. Both distributions can extend above 1.

    Azimuthal distributions for track direction angle (psi) for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Should be flat within statistics, except for the 12-sector structure in the TPC-only global tracks.

    Pseudorapidity (eta) distributions for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. TPC track distribution should be symmetric about eta=0. SVT+TPC track distribution may be non-symmetric depending on the distribution of primary vertices.

    Transverse momentum (GeV/c) distributions for TPC-only (dashed line) and SVT+TPC (solid line) global tracks.

  • Page 9

  • Chi-square per degree of freedom for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Both should peak just below 1.

    Probability of chi-square for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Both should have strong peak at 1.

    Distribution of the number of fitted points on track for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. Peak at low value indicates track splitting. Should see increase near ~45.

    Log-base-10 of impact parameter (in cm) from primary vertex for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. SVT+TPC tracks should have much smaller impact parameter values.

    Impact parameter (in cm) from primary vertex for TPC-only (dashed line) and SVT+TPC (solid line) global tracks. SVT+TPC tracks should have much smaller impact parameter values.

    Scatter plot of number of fitted points on track versus track length (from first to last point along helical path) for both TPC-only and SVT+TPC global tracks. Peak in lower left corner indicates split tracks. There should be some increase for >30 points and lengths from 1 - 2 m.

  • Page 10

  • Distribution of first fitted space point with respect to pad row number for TPC-only global tracks. Should peak at 1 with a minor peak at padrow 14 (beginning of outer sector); the latter should not be too big relative to that at row 1.

    Distribution of first fitted space point with respect to z for TPC-only global tracks. Should be approx. symmetric and flat around z=0.

    Residuals at first point on track for TPC-only global tracks. The quantities plotted are the longitudinal (along z-axis, dashed line) and transverse (in x-y plane, solid line) differences between the coordinates of the first hit and the DCA point on the helix fit to the first point. For the transverse residual, positive (negative) values correspond to hits inside (outside) the circular projection of the helix onto the bend plane. FWHM should be less than ~ 1cm. The two bumps in the solid lines at +/- 2 cm are due to an error in the QA_Maker software and should not appear in the QA plots.

    Distribution of first fitted space point with respect to azimuthal angle (phi) for TPC-only global tracks. The solid (dashed) line is for the east (west) half of the TPC. These should be approximately equal and flat within statistics, except for the 12-sector structure.

    Scatter plot of tangent of dip angle (tanl) versus (z_first - z_primvrtx)/arc-length for TPC-only global tracks and SVT+TPC global tracks whose first fitted point is in the TPC. Variable 'z_first' is the z coordinate of the first fitted point in the TPC. Variable 'z_primvrtx' is the z-coordinate of the primary vertex for the event. Variable 'arc-length' is 2R*arcsin(delta_r/2R) where R = track radius of curvature and delta_r is the transverse distance between the primary vertex and the first hit on track. Primary tracks lie along the 45 deg diagonal. Secondary tracks and strays lie scattered to either side. The diagonal band should appear clearly and be straight and smooth without kinks, breaks or bends.

    Distribution of first fit hits with respect to z for SVT+TPC global tracks which have the first fitted hit in the SVT. Should be flat within statistics but could display steps at the ends due to the SVT layers. Should be approximately symmetric but depends on distribution of primary vertices.

  • Page 11

  • Distribution of radial position of first fitted hits on SVT+TPC global tracks. Tracks on the right side correspond to those in which the SVT space points were discarded by the fitter.

    Residuals at first point on track for SVT+TPC global tracks. The quantities plotted are the longitudinal (along z-axis, dashed line) and transverse (in x-y plane, solid line) differences between the coordinates of the first hit and the DCA point on the helix fit to the first point. For the transverse residual, positive (negative) values correspond to hits inside (outside) the circular projection of the helix onto the bend plane. FWHM should be less than ~ 0.1 cm. Broad, ~1 cm wide tails, could be due to tracks in which the SVT hits were discarded by the fitter.

    Distribution of first fitted space point with respect to azimuthal angle (phi) for SVT+TPC global tracks with first point in the SVT. These should be approximately equal and flat within statistics.

    Scatter plot of tangent of dip angle (tanl) versus (z_first - z_primvrtx)/arc-length for SVT+TPC global tracks with first point in the SVT. Variable 'z_first' is the z coordinate of the first fitted point in the SVT. Variable 'z_primvrtx' is the z-coordinate of the primary vertex for the event. Variable 'arc-length' is 2R*arcsin(delta_r/2R) where R = track radius of curvature and delta_r is the transverse distance between the primary vertex and the first hit on track. Primary tracks lie along the 45 deg diagonal. Secondary tracks and strays lie scattered to either side. The diagonal band should appear clearly and be straight and smooth without kinks, breaks or bends. This should be much cleaner than that for the TPC-only tracks.

    Distribution of the number of fitted points on track for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. Distributions should be similar within statistics and peak at 10.

    Ratio of number of fitted points to estimated maximum number for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. Should peak at ~1. Distributions should be similar within statistics.

  • Page 12

  • Distribution of first fitted space point with respect to FTPC pad row number (West is 1-10, dashed line; East is 11-20, solid line) for FTPC global tracks. These should be similar within statistics and peak at pad rows 1 and 11.

    Azimuthal distributions for track direction angle (psi) for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. These should be similar and flat within statistics except for the hexagonal FTPC sector structure.

    Distributions of absolute value of pseudorapidity for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. These should be similar within statistics and range from about 2.5 to 4.

    Transverse momentum (GeV/c) distributions for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. These should be similar within statistics.

    Total momentum (GeV/c) distributions for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. These should be similar within statistics.

    Log-base-10 of impact parameter (in cm) from primary vertex for FTPC-East (solid line) and FTPC-West (dashed line) global tracks. These should be similar within statistics.

  • Page 13

  • Scatter plot of (x,y) coordinates for the first fitted space points in FTPC-East global tracks. These should be uniformly populated with hits; FTPC hexagonal structure is apparent.

    Scatter plot of (x,y) coordinates for the first fitted space points in FTPC-West global tracks. These should be uniformly populated with hits; FTPC hexagonal structure is apparent.

    Quality flag values for all primary tracks. Some with large, negative values may not appear on plot; check stat. box for underflows. Majority of tracks should have iflag>0, corresponding to good, usable tracks. Refer to: dst_track_flags.html and kalerr.html for description of flag values.

    Good primary track multiplicity distribution for TPC-only and SVT+TPC tracks. Magnitude and width depends on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Scatter plot of good primary track multiplicities in FTPC West versus FTPC East. Distribution should be correlated and lie along the reference diagonal line. Magnitudes and widths depend on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Ratio of good primary to good global tracks for all detectors. Should be of order 1/3 to 2/3.

  • Page 14

  • Mean transverse momentum distribution for TPC-only (dashed line) and SVT+TPC (solid line) good primary tracks. Should peak around 0.4 - 0.6 GeV/c and be fairly narrow.

    Mean transverse momentum distribution for FTPC-East (solid line) and FTPC-West (dashed line) good primary tracks. These should be similar within statistics and peak around 0.4 - 0.6 GeV/c but can have broader distributions than for the SVT and TPC tracks.

    Mean pseudorapidity distribution for TPC-only (dashed line) and SVT+TPC (solid line) good primary tracks. Should peak around 0 but can be fairly broad depending on distribution of primary vertices.

    Distribution of absolute value of mean pseudorapidity for FTPC-East (solid line) and FTPC-West (dashed line) good primary tracks. These should be similar within statistics and peak around 3 - 3.5.

    Azimuthal distributions for track direction angle (psi) for TPC-only (dashed line) and SVT+TPC (solid line) good primary tracks. Should be flat within statistics.

    Pseudorapidity (eta) distributions for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks. TPC tracks should be symmetric about eta=0. SVT+TPC may have slight non-symmetry depending on distribution of primary vertices.

  • Page 15

  • Transverse momentum (GeV/c) distributions for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks.

    Chi-square per degree of freedom for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks. Both should peak just below 1.

    Probability of chi-square for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks. Both should have strong peak at 1.

    Log-base-10 of impact parameter (in cm) from primary vertex for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks. If the primary track refit is constrained to go through the primary vertex then the impact parameter will be very small.

    Impact parameter (in cm) from primary vertex for TPC-only (dashed line) and SVT+TPC (solid line) primary tracks. If the primary track refit is constrained to go through the primary vertex then the impact parameter will be very small.

    Scatter plot of number of fitted points on track versus track length (from first to last point along helical path) for both TPC-only and SVT+TPC primary tracks. There should not be a peak in lower left corner indicating fewer split tracks than for global tracks. There should be a peak(s) for long tracks above 1.5 m.

  • Page 16

  • Residuals at first point on track for TPC-only primary tracks. The quantities plotted are the longitudinal (along z-axis, dashed line) and transverse (in x-y plane, solid line) differences between the coordinates of the first hit and the DCA point on the helix fit to the first point. For the transverse residual, positive (negative) values correspond to hits inside (outside) the circular projection of the helix onto the bend plane. FWHM should be less than ~ 1cm.

    Residuals at first point on track for SVT+TPC primary tracks. The quantities plotted are the longitudinal (along z-axis, dashed line) and transverse (in x-y plane, solid line) differences between the coordinates of the first hit and the DCA point on the helix fit to the first point. For the transverse residual, positive (negative) values correspond to hits inside (outside) the circular projection of the helix onto the bend plane. FWHM should be less than ~ 0.1 cm. Broad, ~1 cm wide tails could be due to tracks in which the SVT hits were discarded by the fitter.

    Azimuthal distributions for track direction angle (psi) for FTPC-East (solid line) and FTPC-West (dashed line) primary tracks. These should be similar and flat within statistics except for the hexagonal FTPC sector structure.

    Distributions of absolute value of pseudorapidity for FTPC-East (solid line) and FTPC-West (dashed line) primary tracks. These should be similar within statistics and range from about 2.5 to 4.

    Transverse momentum (GeV/c) distributions for FTPC-East (solid line) and FTPC-West (dashed line) primary tracks. These should be similar within statistics.

    Log-base-10 of impact parameter (in cm) from primary vertex for FTPC-East (solid line) and FTPC-West (dashed line) primary tracks. These should be similar within statistics.

  • Page 17

  • Distribution of ratio of mean dE/dx to Bethe-Bloch dE/dx for pions at the same momentum for TPC-only and SVT+TPC global tracks. Should peak at ~1. Tests calibration of charge deposition in TPC gas.

    Scatter plot of truncated mean dE/dx versus total momentum (GeV/c) for TPC-only and SVT+TPC global tracks. Should be able to see Bethe-Bloch bands for pions, kaons and protons.

    Distribution of primary vertex position along the z-axis out to abs(z) < 50 cm. This should correspond to the RHIC bunch length, crossing and cogging information.

    Scatter plot of the (x,y) coordinates of the primary vertex position. This should correspond to the determined beam transverse position. The amount of dispersion will depend on the trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Azimuthal distribution of V0 vertices relative to the primary vertex for each event. Should be flat within statistics.

    Radial distribution of V0 vertices relative to the primary vertex for each event. Should fall off steeply with most vertices within ~10 cm.

  • Page 18

  • Longitudinal (z) distribution of V0 vertices relative to the primary vertex for each event. Should fall off steeply with most vertices within ~10 cm.

    Total number of V0 vertices found in each event; should scale with multiplicity. Range depends on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Invariant mass plot of V0 vertices using Lambda decay hypothesis. Sometimes possible to see Lambda peak for low- and mid-multiplicity events.

    Invariant mass plot of V0 vertices using K0-short decay hypothesis. Sometimes possible to see K0-short peak for low- and mid-multiplicity events.

    Total number of Xi vertices found in each event; should scale with multiplicity. Range depends on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

    Total number of kink decay vertices found in each event; should scale with multiplicity. Range depends on trigger condition and multiplicity cut for this set of plots (i.e. low, medium or high).

  • Page 19

  • Difference between the geant and reconstructed primary vertex position along coordinate x (cm). For simulations only.

    Difference between the geant and reconstructed primary vertex position along coordinate y (cm). For simulations only.

    Difference between the geant and reconstructed primary vertex position along coordinate z (cm). For simulations only.