Abstract
A study of the decays Bs0 → μ+μ− and B0 → μ+μ− has been performed using 26.3 fb−1 of 13 TeV LHC proton-proton collision data collected with the ATLAS detector in 2015 and 2016. Since the detector resolution in μ+μ− invariant mass is comparable to the Bs0 -B0 mass difference, a single fit determines the signal yields for both decay modes. This results in a measurement of the branching fraction B(Bs0→μ+μ−)=(3.2+1.1−1.0)×10−9 and an upper limit B(B0→μ+μ−)<4.3×10−10 at 95% confidence level. The result is combined with the Run 1 ATLAS result, yielding B(Bs0→μ+μ−)=(2.8+0.8−0.7)×10−9 and B(B0→μ+μ−)<2.1×10−10 at 95% confidence level. The combined result is consistent with the Standard Model prediction within 2.4 standard deviations in the B(B0→μ+μ−)−B(Bs0→μ+μ−) plane.
Original language | English |
---|---|
Article number | 98 |
Number of pages | 47 |
Journal | JHEP |
Volume | 2019 |
Issue number | 4 |
DOIs | |
Publication status | Published - 15 Apr 2019 |
Bibliographical note
44 pages in total, author list starting page 28, 10 figures, 3 tables, submitted to JHEP. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/BPHY-2018-09Keywords
- Hadron-Hadron scattering (experiments)
- hep-ex