Log entry time 08:31:33 on October 19, 2010

Entry number 335606

Crew:
J. Roche
Y. Zhihong
P. Nadel-Turonski
 

Highlights:
Beam could not be delivered through the Compton chicane (one of the dipole failed): took beam straight through.
Taking calibration data on the dvcs calorimeter.
 

Timeline:

• 12:00: getting beam, and going through the Compton chicane.
  The LHRS is at an angle 33.29 deg, the momentum is 2.748 GeV. The dipole NMR signal on the scope is absent, the gui says the NMR is locked. At this time we have no target in beam.
• 12:31: MCC is calling to inform us that the gun has tripped and it will be a few minutes before the beam is back.
• 1:00: MCC is sending tune beam inthe Hall. Oh no, one of the dipole of the Compton chicane fails.
• 3:00: the Compton dipole requieres an access, we decide to bypass the chicane for tonight. Request harps, results look good (A sigmax=0.19 mm, sigmay=0.29 mm), (B sigma x=0.23 mm, y=0.37 mm). Check position on BeO: A-ok.
• Move to 15 cm LH2 target. Request 3 uA unrastered.
• 4:00: did some estimation of deadtime. with run 7543 to 7546.
  4uA beam: 35 Hz of raw rates, 25 Hz of DAQ rates
  3uA beam: 29 Hz of raw rates, 28 Hz of DAQ rates
  2uA beam: 25 Hz of raw rates, 25 Hz of DAQ rates
  
• 5:00: started long run for elastic calibration of the calo.

Run list:

• 33.29 deg, 2.748 GeV:short runs to test dead time: 7543, 7544(3 uA), 7545 (1.2 uA), 7546 (4 uA)
• 33.29 deg, 2.748 GeV:calibration 7551 (42 min, crashed), 7552 (junk), 7553, 7554 (crashed after 10 kevt), 7555 (fine but short), 7556 (crashed after 1 k),7557 (on going at the end of the shift)