Log entry time 09:02:45 on October 14, 2010

Entry number 334807

Crew:
J. Roche
Y. Zhihong
F. Itard
 

Highlights:
Taking calibration data on the dvcs calorimeter.
NMR lock on the LHRS unstable: should be fixed
 

Timeline:

• 11:00: start shift with calorimeter elastic calibration in progress. The kinematic conditions are summarized here . Beam current is 2 uA. Beam is centered A(x,y)=0,0 and B(x,y)=0,0. No raster. Beam energy is 5551.76 MeV. Ps5=1 all others at 0.
• 11:55: E. Fuchey leaves us instructions for Compton running.
• 12:55: MCC takes beam away for a BCM calibration for Hall C.
• 1:30: noticed Compton rates (without cavity on) on increased by ~30%). Eric Fuchey advises me to abort Compton data taking which I did. here
• 3:15: starting kinematic configuration. Run into difficulties to lock the LHRS NMR and chnage the spectro angle. Called Bad for advices: he locks the NMR by hand and sugest to move first the smaller angle and then come back to larger angle. It worked but took a while.
• 4:28: starting data taking at new kinematic for LHRS : Pnom=2.406 GeV, thenom=37.00 deg.
• 5:00: Looked if we could take Compton data again: yes maybe
• 6:10: took two runs with ps1 only in the trigger. Will check timing of the scintillators.
• 6:30: back to DVCS calorimeter calibration.
• 9:00: MCC calls to tell us that they are taking the beam away for beam studies.

Run list:

• Pedestals: 7296, 7300, 7303, 7304
• Elastic calibration (Pnom=2.606 GeV, thenom=34.76 deg, HV=400 V): 7298,7305, 7306, 7307, 7308
• Elastic calibration (Pnom=2.606 GeV, thenom=34.76 deg, HV=500 V): 7316, 7317, 7318, 7319, 7320, 7321
• Elastic calibration (Pnom=2.406 GeV, thenom=37.00 deg, HV=500 V): 7322, 7323, 7326, 7327, 7328, 7329, 7330, 7331
• trigger timing test : ps2=1: 7324, ps1=50: 7325, no other trigger.