summary of target activities today (Tuesday)

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User name jpchen

Log entry time 02:41:46 on October 29, 2008

Entry number 245234

keyword=summary of target activities today (Tuesday)

In the morning, the target spin-up reached 10% polarization for the vertical line. A NMR polarization measurement in both chambers (rotated to longitudinal direction) were performed (by Jin) and were successful. EPR tries (by Chiranjib) were not successful. After the target training in the afternoon, another NMR polarization measurement in both chambers were performed by Jin. Somehow the pumping chamber NMR after rotation gave only half of the height. Don't quite understand why. Maybe the He3 spin did not completely follow the field rotation? In the evening, Joe was trying to replace a BeO target (new one with proper mark), but the target motion did not work. Reboot ioc did not help. With Jack's help, it was traced to a loose connector. After fixed the motion problem, Joe completed the work of replacing BeO foil. After that (~9:30 pm), Ye/Chiranjib/Jin started laser alignment on the vertical line. One possible reason for degraded S-line polarization is the angle of laser light incident to the last two mirrors. The new alignment tried to make both mirrors to be as close to 45 degree as possible. Also we checked the laser back reflection and readjusted. Laser alignment for the vertical line was completed by 2 am. Ye/Chiranjib/Jin are continuing in the hall to measure the laser polazations for P and S lines at various locations. Once this is done, the target chamber will be closed and target work in the hall for today will be completed. Try to get beam after that. The target laser wavelength adjustment will be done from upstairs and then will leave it pump up overnight. Will continue work on EPR tomorrow, first from upstairs during the day. It is ok to put beam on solid targets.