[BLAST_ANAWARE] yet another T20 "result"

From: Chi Zhang (zhangchi@MIT.EDU)
Date: Thu May 27 2004 - 20:37:07 EDT


Hi,

I hope things are starting to make sense. I checked my analysis script I
wrote on shift last weekend, boy they are some buggy codes. I fixed the
bugs I found, added errors due to angulare resolution. an uncertainty of
1.5 degrees for spin angle in LAB frame and a 1degree electron scattering
angle resolution is assumed and the errors are then propagated into spin
angle in CMS and the factors in front of T21, T21 and T22 in asymmetry.

All May data are analyzed. and results for T20 at theta_e=70 degress are
in one of the atatched figures. The other figure is for T21 just to check
consistancy. and for the two bins at lowest Q2, T21 agrees with Abott's
parametrization #1 amazingly. T20 now also look at least hopeful.

Note among the data included, are data on May 05 when close to mid night,
Nicklas reported that ABS4 pump failure. Also inluded are the runs with
"target flip sequence frequency" is not properly set(runs before May 09).
it also included runs on May 10. On that day, after run 7335, Nick again
found SFT failed. So some runs may be bad in polarization. But I do not
have enough statistics to determine polarizations run by run.

I am still having some problem getting as good results from March runs,
with 40cm cell and likely higher polarization.

Chi







This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:31 EST