AuAu 53 GeV - A second look
Executive summary:
Things are looking nice.
Fine tuning the thresholds gives us:
Analysis:
This was run over the 733,013 available events in FastOffline MuDsts in the st_physics stream. I am using the dNdEta.C written by Mike Lisa for this analysis. The only selection right now is:
|Vz| < 50
Vr < 2
Giving us 416781 events (~57% "good" though, no care was taken beyond the above criteria).
The vertex distribution is:
There is a slight offset in the Vy value (~3 mm).
Comparing the vertex with the vertices from the other detectors:
The distribution of vpd vz - vz is centered about ~4 cm, but the VPD has not been timed yet so this will be fixed. I have no idea what the second bump in the BBC Vz distribution is from....
First we can look at the ADC distributions:
drupal.star.bnl.gov/STAR/system/files/ADC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
And the TDC:
drupal.star.bnl.gov/STAR/system/files/TDC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
And the TAC:
drupal.star.bnl.gov/STAR/system/files/TAC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
With some examples:
Note that I plotted these for all tiles, without taking care to only plot those that we know have a signal. We can look at the chart prepared by Mike:
To get an idea. The tiles hooked up to a QT32C with a modified QT8 card currently do not have TDCs.
The can also look at the associated 2D distributions:
TAC vs ADC
drupal.star.bnl.gov/STAR/system/files/TACvsADC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
TDC vs ADC
drupal.star.bnl.gov/STAR/system/files/ADCvsTDC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
TAC vs TDC
drupal.star.bnl.gov/STAR/system/files/TDCvsTAC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
With some examples:
Of course, what we are most interested in is the hit map (thresholds for all tiles are still at their default 10):
Where the fuzziness in phi and eta comes from the vertex position. (An earlier plot without the vertex constrains is much fuzzier.) And of course, dN/deta:
Next I tried to set the thresholds to more reasonable values, this can be seen channel by channel:
drupal.star.bnl.gov/STAR/system/files/Thres_ADC_EPD_EPDhists_F83701A01815F008D704BD0F948359A4.root_.pdf
This did not make much of a difference:
The red is using the default of 10, the black is with a careful-ish analysis.
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