Totally dead tile

 Starting in run 20127001 the tiles associated with West PP2 TT04, linked to channel EQ1 Bd0x1D Ch 10 was dead. The <ADC>, hit count, and TAC were zero.
 Figure 1: QA plot from run 20127006 where one can see zero&nbsp;. This can mean a few things (e.g. huge pedestal in which you would still see non-zero hit count)Figure 1: QA plot from run 20127006 where one can see zero . This can mean a few things (e.g. huge pedestal in which you would still see non-zero hit count)
Figure 2: QA plot from run 20127006 where one can see zero hit counts. This indicates a more serious problem.Figure 2: QA plot from run 20127006 where one can see zero hit counts. This indicates a more serious problem.

Using the
mapping spreadsheet, Annika and I were able to find the relevant channel in the Rx board, disconnected the cable from the Rx board, and connected a scope to the channel on the Rx board. We did in fact see cosmics:
Figure 3: A scope setup to see cosmics out of the Rx board (taken from Xiaoyu's notes)Figure 3: A scope setup to see cosmics out of the Rx board (taken from Xiaoyu's notes)
Also, by changing Vped
  • Done through daqman
  • $ ssh -A you@rssh.rhic.bnl.gov
  • $ ssh stargw.starp.bnl.gov
  • $ ssh -A -X -t evpops@daqman
  • $ cd /RTS/conf/epd/
  • $ cp EPD_TUFFmap.txt EPD_TUFFmap_(DDMMMYYYY).txt
  • e.g. $ cp EPD_TUFFmap.txt EPD_TUFFmap_12Dec2019.txt
  • $ cp /RTS/conf/epd/MappingPatterns2018/Zeros_02262018.txt  /RTS/conf/epd/EPD_TUFFmap.txt
  • In the EPD GUI, click "PHYSICS" on the top bar, then "PHYSICS" in the upper-left-hand box; wait for the yellow circle in "SC State" to finish its loop and turn green.
  • Once finished, we put the state pack to where we found it:
  • $ cp EPD_TUFFmap_(DDMMMYYYY).txt EPD_TUFFmap.txt
  • In the EPD GUI, click "PHYSICS" on the top bar, then "PHYSICS" in the upper-left-hand box; wait for the yellow circle in "SC State" to finish its loop and turn green.
we were able to see the voltage jump in the scope. This meant that either the connector was bad or something about the QT board (or further downstream) was bad. We switched the connector from EQ1-0x1D-B channel 3 to EQ3-0x1D-D channel 1.

You can see the full discussions at 
https://www.star.bnl.gov/HyperNews-star//protected/get/epd.html?maxm=200 (EPD missing tile by Rosi Reed, 2019, May 16; EPD Access activities by Rosi Reed, 2019, May 20; Summary of Events 5/22/19 by Justin Ewigleben, 2019, May 22)