1.) Readout:
PCboad being design to drive helix card. Need to feed through
analog signal outputs as well as power (5 V, 3 V, +/-2 V) feeds.
Will attempt to wire bond Helix board to GEM readout pitch adatper
next week.
2.) Test Apparatus
First prototype has been dissassembled in order to upgrade with a
third GEM foil. Attempting to schedule July 22 for detector
assembly in the cleanroom.
Signals from Iron (Fe) have been observed at LaTech in the Second
proto-type GEM built at CERN by our student Jeremy Dobbins (16
outputs have been tied together and there is NO premplifier like
the HELIX board).
Signals from our 8 keV X-ray tube have also been observed at LaTech in the Second
proto-type. The image shown a negative pulse from the 16 GEM
detector output which have been tied together and the positive
pulse is the output from the last GEM foil. As in the previous
pictures, none of these signals have been amplified.
We are currently trying to decide if we should move the trigger
from the last foil (bottom of 3rd GEM preamp) to the 2nd to last
foil (top of 3rd GEM preamp) in order to have a negative going
trigger pulse. Our AMPTEK preamplifier is designed for negative
going input pulses.
