User name x. jiang
Log entry time 14:38:38 on January22,2001
Entry number 55435
keyword=right-arm x vs. y distribution at VDCNilanga and I looked at the x vs. y distribution at VDC (u1_plane) in the right-arm
for run-1622. We saw a clear focusing strip in the middle, with some scattered events spread all around, clearly marked the boundry of the VDC in the
y-direction.
So, our conclution is that the zero-vdc-hits events are real electrons which missed
the VDC. They might be secondary scattered electrons , from the pole face of magnets, for example. The question remains on how to get rid of these junk
electron events . But at least, the data seems to be fine at the moment.
FIGURE 1
FIGURE 2
