VUB-RECOIL Archives

Vub measurement using recoil of fully reconstructed Bs

VUB-RECOIL@LISTSERV.SLAC.STANFORD.EDU

Options: Use Forum View

Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Daniele del Re <[log in to unmask]>
Date:
24 Jun 2002 08:17:33 -0700 (PDT)Mon, 24 Jun 2002 08:17:33 -0700 (PDT)
Content-Type:
TEXT/PLAIN
Parts/Attachments:
TEXT/PLAIN (67 lines)

Hi all,

 these are the results for the B0-Bch and muons and electrons breakdown:

 All:

 BRBR :0.0154+-0.0031

 (here the result is a bit different with respect to the one in the BAD
since I change a bit the mes fit strategy to make it more stable).


 Electrons:

 BRBR :0.0133+-0.0047


 Muons:

 BRBR :0.0215+-0.0048


 B0:

 BRBR :0.0029+-0.0040


 Bch:

 BRBR :0.0276+-0.0047


 As you see, the result for ele-muons is fine. For the B0-Bch the two
numbers are very different.


 I checked all the mes fit and the numbers for those results and they seem
to be ok. In order to understand if this is a problem of the background
subtraction I performed the scan as a function of Mx.

 Here the result:

 http://www.slac.stanford.edu/~daniele/vub/newmxstudy.ps


 Look at the last page. Plots on the left are the one obtained with the
three shapes fit. The left ones are obtained with the bkg subtraction.
Top ones are B0's, bottom ones are Bch's.

 There could be a trend, in opposite directions for B0 and Bch. In
priciple in B0's the background could be overestimated and for Bch the
opposite. With this statistic is difficult to get a conclusion. BTW, even
in the 1.2 GeV bin (the point with the smallest discrepancy) a 2.5 sigmas
effect is present.

 On the generic MC the results for B0 and Bch are reallly compatible and
then it cannot be a problem of the machinery.


 Daniele






ATOM RSS1 RSS2