This web page summarizes the results of the search for exotics in the J/&psi &phi Mass Spectrum in B+
→ J/ψ φ K+ decays.
The search is based on data comprising 2.7 fb-1 of integrated luminosity.
Using the fully reconstructed decay
B+ → Y(4140)K+; Y(4140) →J/ψ φ ; J/Ψ → μ+μ-; φ → K+ K-
we measure:
-
m
= 4143.0 ± 2.9 (stat.) ±
1.2(syst.) MeV/c2
-
&Gamma
= 11.7 + 8.3 - 5.0 (stat.) ±
3.7(syst.) MeV/c2
The statistical significance of the &Xib signal is over 3.8 &sigma
 |
| GIF EPS |
 |
| GIF EPS |
Major points of the analysis
- Use Lxy to separate B vertex from primary vertex
- Use kaon particle identification to reduce combinatorial background
Plots
- B sideband subtracted invariant mass of KK GIF, EPS
- Dalitz plot GIF, EPS
- B mass before applying Lxy and kaon PID GIF, EPS
- B mass before applying kaon PID but after Lxy GIF, EPS
- Control signal B+ → J/ψ K+ GIF, EPS
- Control signal Bs → J/ψ φ GIF, EPS
- Dalitz plot from phase space Monte Carlo GIF, EPS
- Mass difference from phase space Monte Carlo GIF, EPS
- Dalitz plot from Bs contamination channel (Monte Carlo) GIF, EPS
- Mass difference for Lxy >100 um GIF, EPS
- Mass difference for vertex probability>0.00001 and # of SVT hits>=3 GIF, EPS
Documentation
- The Fermilab Wine&Cheese talk can be found here: ppt
- arXiv:0903.2229 [hep-ex]