Attached is a file of the meantime of LTOF3 (y-axis) vs. RTOF12
(x-axis). This is similar to the plot that Genya made yesterday
except that he plotted the TDC differences of L vs. TDC
differences of right to get coplanarity. When you plot the
meantimes as here, the events are tightly bunched, and a
second peak becomes visible. Note the expanded x and y scales.
For fixed LTOF number, the stronger peak on the lower right
is concentrated at the RTOF +/- 1 corresponding the the recoil
proton angle. It essentially vanishes quickly outside this
range. The weaker peak to the upper left simply gets stronger
for more forward angle RTOFs and thus does not show the expected
e-p correlation. My interpretation of this peak is that maybe
it is due to Moeller scattering, althoughthe energy of recoil
electrons from Moeller scattering at this large angle should
be too small.
It will clearly help to have working L and R Cerenkovs.
One thing that I did not do was to correlate Genya's plot and
mine. A window around one should pick out the other.
-- John R. Calarco Dept. of Physics Univ. of New Hampshire Durham, NH 03824 phone: (603)862-2088 FAX: (603)862-2998 email: calarco@unh.edu
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