Revision as of 16:50, 2 November 2010

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This page is in progress, please new items to it. When you obtain a result, log in into the Halog and link it to this page. if you are willing to take charge of a given analysis, please indicate it on this page as well as the date at which you are starting to work on it.

Matching data taking with run plans

• Update the how to
• Maintain db_run.dat file: Make sure that every LHRS momentum and angle changes are logged (Florian Itard is keeping up with that)
• Database of run indicating line by line the run number, the target in position, the average beam current, LHRs pnom, LHRS angle, the purpose of the run

[/u/home/cshloka/public_html/halla[Statistic summary]]

Luminosity, efficiency

Boiling test

Initial calibration on 10-17 owl shift: [shift summary][initial plan]
Second calibration on 10-21 swing shift: [run list]

Trigger efficiency

Analyze data taken on the week-end of 10-09 and 10-10 with T3 and T4 trigger and also data taken around 10-14. Online analysis by B. Michaels [here]. Malek Mazouz is working on the offline study (starting on 10-16)

Run7711 T3 and T4 Triggers

S0 hit pattern vs x and y (at vdc) shows efficiency in excess of 99% except at extreme ends of focal plane halog entry 336817 http://www.jlab.org/~adaq/halog/html/1010_archive/101026122751.html

Cut script saved at /adaqfs/home/adaq/dvcs/onlana/GoodHRS.h TCut cGoodVDC = "L.tr.n==1&&abs(L.tr.x)<1."; TCut cGoodAngles = "abs(L.tr.tg_th)<0.1&&abs(L.tr.tg_ph)<0.05"; TCut cTarget = "abs(L.tr.tg_y)<0.1"; TCut cCleanTrk = cGoodVDC&&cGoodAngles&&cTarget;

Deadtime

• Buffered mode (10-28): [this halog]
• info about livetime from TS registers [this halog]

LHRS commissioning

Calibrate the ADCs:

Still to be done S1, Pion rejector, (Shloka is working on that)

[Cerenkov], [S2 (done 10-09)]

Calibrate detector time spectra:

Still to be done : understand timing spectra for S1,S2 and the Cerenkov

• [t0 for VDC (done 10-09)]
• [pion rejector]

Evaluate PID efficiency:

• November 1: [online results] result in [lowering the threshold]

LHRS optics run (no sieve/sieve)

Ye Zhihong is interested in this analysis and started it.

• [Summary of runs so far]
• [Initial invariant masses on LH2]
• [5 passes beam sieve holes on C foils and LH2]

LHRS acceptance check

[delta scan on 10-22] need to be analyzed

DVCS Calorimeter

• two photon invariant mass: [10-24]

Elastic calibration

• 4 passes : [October 26 Day], [October 26 Swing]

Beam

BPM calibration

• [Initial calibration]

BCM calibration

• the initial calibration was done on 10-14 [halog]. Calibration results are [here]

Beam energy measurement

• the initial measurement was done on 10-15: [halog]

Helicity

• ring map file
  • November 1: new configuration [here]
  • September 20: ring map file [here]
• runs with TSettle as trigger:
  • 7387: after the new helicity board is installed: [here]
  • test at various helicity flipping rate: [here]

Polarization

• Sign:
  • Polarization sign: [same sign HV in or OUT??]
    
• Moeller
  • [Moeller 10-27]
    
  • [Moeller 10-03]
    
• Compton
  • [first results]