Hi,
15 channels out of 1300 does not seem a terrible problem. This was
another check. The question was also whether the gain has shifted.
(taking into account the pedestal shift) particularly w/ the tubes
that seem to have changed the most.
Adrian should look at it while the hall is open
-- ________________________________________________________________________________ Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124 research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^On Fri, 8 Nov 2002, Peter Karpius wrote:
> Here's what I would've sent had there been no network outage: > > Before Beam > > RUN 2652 cosmics run to determine the neutron counter pedestals. > The pedestals range from approx 155ch to 400 ch. > > RUN 2654 cosmics run to study TOF pedestal shift and RT6, RB10. > There seems to be a shift of 5-15 channels for most > channels with respect to the values in the calibration > file blast.sc_cal. The shift is not systematic however, > as some are shifted up and some are shifted down. There > seems to be a marked difference in a few channels like RB14, > RB11, RB10, RB8. > > > Beam tuning continued for much of the shift. During this time we > continued the software effort. > > At 22:20 we were given the beam. CCR had told us that they had optimized > the beam w.r.t. lifetime. But since we had no phys trigger data on this > we decided to do a slit position study. Between the slits being all the > way out and the optimal position there was approx a factor of 6 difference > in normalized rate. > > Optimal slit position:L=-4, R=16, T=5, B=-6 > See the logbook for details. > > RUN 2655 No Gas, 230K elastic_tof_last8.settings > > (not analyzed yet) > > During this run the timing of the LNC LMLU input was checked against the > last 8 LTOF's. All of these TOF signals seemed to occur for the most part > within the bounds of the NC pulse (0-40 nsec jitter). > > We tried putting the LNC as a 1 in the LMLU but this dropped the rate to > 2-3 Hz so we put it back in x-mode and continued taking data. > > RTOF4T showed no signal on scalers or scope. Checked dumb terminal and > saw that this tube draws no current. Check HV connection at next > convenience. > > RUN 2657 Gas at 0.5 SCCM, elastic_tof_last8.settings still running at > shift change. > > > > ---------------------------------------------- > Pete Karpius > Graduate Research Assistant > Nuclear Physics Group > University of New Hampshire > phone: (603)862-1220 > FAX: (603)862-2998 > email: karpiusp@einstein.unh.edu > http://pubpages.unh.edu/~pkarpius/homepage.htm > ---------------------------------------------- >
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:28 EST