Log entry time 08:15:27 on October 12, 2010

Entry number 334494

Crew:
J. Roche
F. Itard
V. Bellini
 

Timeline:

• 00:00: start night with run 7205 in progress
  : LH2 target, no sieve, pnom=3.194 GeV (Elastic -4%), theta=27.5 deg
  : beam position: A(x,y):-0.3, 0.3, B(x,y):0,0, 0.4. J. Huan reports that trying for a better cntering get the ions chamber to trip. We leave the beam position as is.
  : MCC is trouble shooting the FFB that cannot be locked on both Hall A and C atthe same time. FFB is off.
  : data acquisition rate= 71 Hz at 10 uA and with the following prescales: ps1=0,ps2=0,ps3=1,ps4=1,ps5=0,ps6=0,ps7=0,ps8=1000,ps9=0
  
• M. Friend is in the backroom looking at the Compton ( here).
• 1:50: Done with Elastic optics without sieve slit. We are taking a short run with ps1 trigger only to check timing spectra with the S2 as a trigger only: run 7207.
• 2:00: changed target to Carbon foils + change magnet momentum setting
• 3:00: request 50 uA MCC will only give us 25 uA, Abort Carbon foils program.
• 3:22: put LH2 15 cm in, put sieve in position.
• 3:33: request 10 uA on LH2.Rates with sieve=38 Hz
• 4:53: instabilities in the mchine, MCC tasks the beam away.
• 5:23: beam is back. MCC had to calibrate the Hall C bcms as Hall C was finally taking significant beam (20uA)
• 7:35: MCC takes beam away to do a QE scan
• Vincenzo notices that the running conditions have changed without apparent reasons. The trigger rates went up and we lost the pattern due to the sieve slit.

Run list:

ps1=0,ps2=0,ps3=1,ps4=1,ps5=0,ps6=0,ps7=0,ps8=1000,ps9=0

• 7205: LH2 target 15cm, no sieve, pnom=3.194 GeV (Elastic -4%), theta=27.5 deg, sieve out, 541 k events
• 7206: junk

• 7207: LH2 target 15cm, no sieve, pnom=3.194 GeV (Elastic -4%), theta=27.5 deg, sieve out, 320 k events

• 7208: Carbon optics, pnom=3.327 GeV (Elastic 0%), theta=27.5 deg, sieve out, 25 uA. Very low rate: 29 Hz.
• 7209: LH2, pnom=3.327 GeV (Elastic 0%), theta=27.5 deg. Sieve in.
• 7210: LH2, pnom=3.327 GeV (Elastic 0%), theta=27.5 deg. Sieve in.
• 7211: LH2, pnom=3.327 GeV (Elastic 0%), theta=27.5 deg. Sieve in.