User name M. Liang
Log entry time 20:09:10 on September 21,1999
Entry number 26899
keyword=low efficiency due to background?
Finished gamma,p at this momentum setting. We go back to resume data taking on gamma,d. The online analysis reproduced the zero hits and efficiency observed previously in gamma,d run in Harm vdc and rear chamber of fpp, which indicates the background we observed is real. Bogdan suggested that we use the Earm, set to the same angle and momentum as Harm, to measure the background, if it comes from neutral particles.
Set Earm to 61.0 deg, Vernier reading -55.7, momentum 1.216 GeV/c. T1 rate is about 50 Hz, so we set the prescale factor ps1 to be 2.
Start Run 1725, measuring background with Earm.