The AuAu running is going into the last 10 days of running. With the very succesfull running in the last 24 hours (~940k trigger six in two
shifts) the survey program is essential complete and we have stated taken data at 12 deg.
Based on discussion within the collaboration the recomendation (from today's meeting here at BNL), and I trust in agreement with the majority
of posted collaboration ideas.
(all units in terms of trigger 6)
a) Continue high statistics running at 12 deg until end of run
- 1M A,B with 1/2 field (.9M A done)
- short 0-field run
- 4-8M at 2/3 field
b) complete some MRS 90 deg low field
- collect ~1.5M at 40 deg for possible HBT (and understanding of this)
- collect at 90 deg with 6B for remainder of run ~3-7 M. (with give upto 20-30 protons per 200 MeV/c at 3-4 GeV/c)
The plan as well as accomplishments since ~10/15 can be found on the web summary
http://pii3.brahms.bnl.gov/~operator/shifts/RunStatistics2001.htm
A few works on feasibility and expectations.
- based on a rapid analysis of run 5812 (only) with ffs tracking (good status, good swin, tight Ty) we get about 1 count/100K trigger 6 per 200MeV/c ptbin at 3 GeV/c (at 15 GeV/c just above the P.ref.) an extrapolation to 4 GeV/c being outside the favourable acceptance might give 0.02-.03 in the same pt-width.
Thus the expected rate may be in order 10 per 1M at 3 Gev/c and .3 at 4 GeV/c with a maximum of 100, and 3 in the remainder of the run.
This the needs effeciency factors for Back FFS (a good fraction of the tracks in the optimum p range will go through the full spec though
not all . To optimize acceptance for pt~ 2-4 give the recommended value of 2/3 in field setting. As you can see to get any reasonable statistics
one has to stick with essentially one setting.
This is also a last call for 'missing' settings i.e. short <=200K of previously taken one,
that for one or another reason has problems.
regards
Flemming
------------------------------------------------------
Flemming Videbaek
Physics Department
Brookhaven National Laboratory
tlf: 631-344-4106
fax 631-344-1334
e-mail: videbaek@bnl.gov
------------------------------------------------------
Flemming Videbaek
Physics Department
Brookhaven National Laboratory
tlf: 631-344-4106
fax 631-344-1334
e-mail: videbaek@bnl.gov
This archive was generated by hypermail 2b30 : Thu Nov 15 2001 - 15:59:28 EST