This web page summarizes the results of
the search for the new heavy baryons Σb
and Σb*
based upon 1.1 fb-1 of data.
The results were initally blessed in the B group meeting on Sept. 21, 2006. Updates to these results were blessed in the B group meetings on Dec. 14, 2006; Feb. 15, 2007; and May 10, 2007. Using the fully reconstructed decay mode
The results were initally blessed in the B group meeting on Sept. 21, 2006. Updates to these results were blessed in the B group meetings on Dec. 14, 2006; Feb. 15, 2007; and May 10, 2007. Using the fully reconstructed decay mode
Σb(*)±→Λb0π±; Λb0→Λc+π-; Λc+→pK-π+
we measure:
- m(Σb+) = 5807.8+2.0-2.2(stat.) ± 1.7(syst.) MeV/c2
- m(Σb¯) = 5815.2 ± 1.0(stat.) ± 1.7(syst.) MeV/c2
- m(Σb*+) = 5829.0+1.6-1.8(stat.) +1.7-1.8(syst.) MeV/c2
- m(Σb*¯) = 5836.4+2.0-1.8(stat.) +1.8-1.7(syst.) MeV/c2
The probability for the background
to produce this signal is below the 5σ level.
A more detailed summary of the results can be found here: pdf
Below are the eps and gif versions of all figures meant for downloads.
- PRL Figure: Σb mass plot in MeV/c2: [eps][gif]
- Figure 1: Fit with the Σbhypothesis
(full range in Q):
histogram [eps]
[gif];
points [eps] [gif]
- Figure 2: Fit with the Σbhypothesis (small range in
Q): histogram [eps]
[gif];
points [eps] [gif]
- Figure 3: Λb0→Λc+π- reconstructed mass: [eps] [gif]
- Figure 4: Blinded Q distribution: [eps] [gif]
- Figure 5: Unblinded Q distribution: [eps] [gif]
- Figure 6: Fit with the null hypothesis: histograms [eps] [gif], points
[eps] [gif]
- Figure 7: Fit with the two peak hypothesis: histograms [eps] [gif];
points [eps][gif]
