Hi all,
today I've run again two fit tests, one with the ratio signal/peaking
bkg fixed (only on data, this time) and one without fixing the ratio.
Results can be found here:
http://www.slac.stanford.edu/~petrella/tmp/scra/Ibutest_fixed/
http://www.slac.stanford.edu/~petrella/tmp/scra/Ibutest_SUN/
General comments:
comparing the right lower plot (which contains the sum of Bch and B0
for data)
http://www.slac.stanford.edu/~petrella/tmp/scra/Ibutest_fixed/test_fixeddatachop_all1.eps
http://www.slac.stanford.edu/~petrella/tmp/scra/Ibutest_SUN/test_SUNdatachop_all1.eps
we see that the effect of fixing the ratio is to increase the
distribution in the low mx region ( 1.55 < mx < 2.1) and to decrease in
the high mx region (mx > 2.8 ).
So we looked with more attention to fits performed bin by bin to compute
the correction factor and...:
 the fit in the high mx region for MC depleted has peaking background
consistent with 0
http://www.slac.stanford.edu/~petrella/tmp/AWG38/depleted/MCsameEND/MCfit_1D_3.103.40.eps
http://www.slac.stanford.edu/~petrella/tmp/AWG38/depleted/MCsameEND/MCfit_1D_3.403.70.eps
moreover in the Enriched MC the signal and the peaking components are
swapped for 3.1 < mx < 3.4!
http://www.slac.stanford.edu/~petrella/tmp/AWG38/enriched/MC/MC_enrich_1D_3.103.40.eps
 in the low mx region the increase in the mx distribution is due to the
behaviour of the double ratio (sig/peak)_DATA/(sig/peak)_MC, where the
numerator and denominator go in the opposite direction i.e.: for MC the
ratio is small while for data is high, so the net effect of the double
ratio is to give a high correction.
But fits on MC present clearly some problems: look at
http://www.slac.stanford.edu/~petrella/tmp/AWG38/depleted/MCsameEND/MCfit_1D_1.551.90.eps
http://www.slac.stanford.edu/~petrella/tmp/AWG38/depleted/MCsameEND/MCfit_1D_1.902.20.eps
So I don't think we can trust 100% the numbers used to compute the
correction so far.
Antonio
