Mass and Width Measurement of Orbitally Excited (L=1) B**0 Mesons

Primary authors: Andreas Gessler, Jen Pursley, Petar Maksimovic, Thomas Kuhr, Michal Kreps, Michael Feindt

This webpage summarizes the blessed results for the observation of the orbitally excited (L = 1) B**0 mesons in the fully reconstructed decay B**0 → B+ π- or in the decay B**0 → B+* π- (B+* → B+ γ), where we do not detect the γ.

The B+ mesons are fully reconstructed in three decay channels:
B+ → J/ψ K+ (J/ψ → μ+ μ- ),
B+ → D0 π+ (D0 → K+ π- ), and
B+ → D0+ (D0 → K+ π- ).

The results have been produced for the summer conferences 2007 and were blessed in the B Physcis Meeting on Thursday July 26, 2007. Updates to these results were blessed in the B Physcis Meeting on Thursday July 3, 2008.

We measure Q values ( m(B+ π-) - m(B+) - m(π-) ) of:

Q(B2*0) = 321.5+1.7-1.8 (stat.) +0.9-0.7 (syst.) MeV/c2
m(B2*0) - m(B10) = 14.9+2.2-2.5 (stat.) +1.2-1.4 (syst.) MeV/c2
And Γ(B2*0)
Γ(B2*0) = 22.7+3.8-3.2 (stat.) +3.2-10.2 (syst.) MeV/c2

The resulting mass measurements of this analysis are:

m(B10) = 5725.3+1.6-2.2 (stat.) +1.4-1.5 (syst.) MeV/c2
m(B2*0) = 5740.2+1.7-1.8 (stat.) +0.9-0.8 (syst.) MeV/c2

A more detailed summary of the results can be found in this public note.

Below are all blessed figures for downloads.

Bellow are plots with some more details showing data in separate B+ channels, with and without fit and NN output distribution to demonstrate separation between signal and background.