_. Polarization Tom Devlin Rutgers/CDF. Strong polarization seen in fixed-target experiments where jet NOT observed. Is it due to the hard collision?. Is it due to fragmentation?. QCD Meeting October 1, 2004. Status and Plans. Three known contributions to dataset:
Strong polarization seen
in fixed-target experiments
where jet NOT observed.
Is it due to the
Is it due to
October 1, 2004
Three known contributions to dataset:
-- Ks Background
-- Continuum 2-track background
MC code exists to generate first two.
Coding in progress for the third.
Generate 20 MC of each type for each real event.
Mix three MC samples, in appropriate proportions
to produce 20 MC events for each real event.
Adjust proportions of each and assumed polarization
of MC ’s to fit data.
Fit with no Mass Constraint: Assume Daughters are p
Subtract signal, Smooth Remainder (5-bins)
Two Major Improvements In This
Eliminate e+e- Cut Events with M2(ee)<0.01
Extended Momentum Range
from 2-12 GeV/c to 2-20 GeV/c
Study , Ks, Background vs.
Momentum and Flight Distance Lxy
For one bin in p and Lxy: (loose-cut ) – (tight-cut ),
(tight-cut Ks), plot both vs. M2(p)
Sum of two plots = Ks + background
Subtract from loose-cut Number of pure
Evaluate Fractions of , Ks and