Operators: franklin ---- ----
Data taking on polarized deuterium continued throughout this shift. There are a few concerns. From run sheets, the beam lifetime dropped yesterday afternoon from 18 to 15 minutes. It's not clear why (BLAST PS rampdown?) and it has not recovered. There have been a few intermittent bad fills where BQM's are very high and lifetime is short. Wire chamber signal-noise is also rather poor as noted previously in elog. A brief investigation of slit positions did not improve things. However, Vitaly has been analyzing the data remotely and says that the target retains good polarization and that the data are coming in at a good clip. Deadtime is as Tancredi documented last night. So we are pressing on.
VZ advocates running full target until tomorrow night since data continue to look good. This seems like reasonable to me since the decision to run a full day of empty target was somewhat arbitrary.
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