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Logistic information

 Toll-Free Number (U.S.&  Canada):  888-240-2560
 PARTICIPANT CODE:                  # 585 129 220
 Room IRL:                            <none>


Please post slides in haplog or docdb, before the meeting

  1. Siyu
    • Watercell precision and systematics
    • comparing central value +/- error for various sieve holes and measurements.
  2. Ryan:
    • verifying the PREX database


  1. Ryan: Residuals from L/R HRS (elog:4114, elog:4117)
    • theta and phi look better, but still have some systematic offset.
      • Siyu thinks this is a bug or incompleteness of the residual script and will contact Ryan about how to fix it.
      • Kent suggests that the angle be calculated by the survey to compare to the predicted value by hand, for a couple of holes, to prove we are doing it right.
    • dp looks systematically wrong, with phi dependence and a theta dependence to the residual.
      • Siyu thinks this might be a data base not fully optimized.
      • Ryan will get the script to output the expected value for dp for each hole, to see if the problem is database outputting bad data or the residual program mis-calculating the expected value
    • there is a separate problem of fits for some holes not converging or returning junk. This requires diagnoses, and perhaps easier tools to review the fits for each hole in theta, phi, dp.
  2. Siyu is looking at the fit from water cell runs
    • he looks at the difference in momentum between the G.S. and first excited state. He also looks at dp for the individual peaks.
    • cutting the data into small bits over the long run, he sees a shift between the beginning and end of the run on the dp of the individual peaks.
      • This _might_ be related to the drift in energy over run, which can be tracked using the energy monitor readback. This is still to be confirmed.
    • he has also made progress on looking at all holes and comparing results over the sieve pattern. This is complicated by a difference in rates (and therefore, a difference in statistics or in time over which the averaging is done).
    • Siyu will post his slides in the haplog after the meeting.


Ryan, Siyu, Devi, Dustin, Chandan, Nilanga, Bob, Kent