S117 meeting 13.06.95
DE-E gaps
The gaps in the spectra of the particle hodoscopes, the hodoscopes, and the silicon arrays should disappear
now. Volker has written new gain factors and offsets in the database. It is after an init_online available on
the hit level.
PID
Volker presented a from Mahis and Andrei different 3rd method matching detectors and performing a
PID. In a log-log representation of the DE-E maps the gain factors can be canceled out by shifting the
spectra in DE and E. The DE shift is done by using the silicon alpha source calibration, the E shift by
using an energy slice through the alpha-branch and adjusting the peaks. Bands through the particle
branches identify the charges, the data between the bands get a number according to their relative DE-
distance to the bands enclosed in. He showed the PID projection of 16 selected detectors at 100 AMeV and
1000 AMeV. But there still seems something to be wrong and has to be checked in the 2 dim
representation (bands at both energies, punchtrough). The advantage over Mahis method is, that Volker
has to not draw the bands for every detector. The log scale has to be checked further since the low energy
region is expanded and the high energy region is compressed represented.
It would be nice if we could compare Mahis and Volkers method next time with the same data set.
Another Idea from Josef came up, to perform an chi2 test on a DE-E map or a part of it in order to match
different detectors. Volker will have a try.
DAQ
since there will be a lot of calibrations in PAW, Walter will give a short (30 min.) introduction in the
database capabilities of PAW in the next meeting.
June 13th, 1995 Carsten Schwarz,