Hi all,
after the booking of all the run1 ntuples
(see
http://www.slac.stanford.edu/BFROOT/www/Physics/Analysis/AWG/InclusiveSL/islrecoil/Staged_data.html
)
I've spent some times looking at the impact of the changing bkg in my
study. The vub MC is all the vub mix one (no changing bkg). For vcb MC
i've selected 4 different SP3 samples with different bkg files
x10, x11, x12 and x15
I've also studied the impact of the Kinematic fitting (with |Mnusq|<0.6
GeV2).
Here you can find the link to some useful plots:

EFFECT OF KIN. FITTING

old study:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/old_stu/MEvents9.eps
introducing the kin_fit:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/old_stu_F/MEvents9.eps

Sigma & Mean of the core gaussian for the Mx resolution with kin. fit.
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/vub_neu/fit/Meandist_9.eps
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/vub_neu/fit/Sigdist_9.eps

Sigma & Mean of the core gaussian for the Mx resolution without kin. fit.
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/vub_neu/nofit/Meandist_9.eps
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/vub_neu/nofit/Sigdist_9.eps

The sigma and the mean using the kin fitting are slightly better, but the
net effect on the optimization study is negligible. (Probably we need to
investigate a larger cut on MMis)

BKG IMPACT

x10:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x10/fit/MEvents9.eps
x11:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x11/fit/MEvents9.eps
x12:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x12/fit/MEvents9.eps
x15:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x15/fit/MEvents9.eps

The impact of the bkg change seems to be negligible in the optimization
study.
However the Sigma and Mean of the distribution of the Mx residuals are
showing different behaviors. for example:
x10:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x10/fit/Sigdist_9.eps
x11:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x11/fit/Sigdist_9.eps
x15:
http://www.slac.stanford.edu/~asarti/recoil/kin_bkg/x15/fit/Sigdist_9.eps

Comments and questions are welcomed.
CU at the meeting
Alessio

______________________________________________________
Alessio Sarti
 Universita' & I.N.F.N. Ferrara
 tel  +39-0532-781928  Ferrara

"Quod non fecerunt barbari, fecerunt Berlusconi"

"Che il bianco sia bianco, e che il nero sia nero
 che uno e uno fanno due e che la scienza dice il vero....
 DIPENDE !"