Observation of an Excited B[± over c] Meson State with the ATLAS Detector

A search for excited states of the B[± over c] meson is performed using 4.9  fb[superscript −1] of 7 TeV and 19.2  fb[superscript −1] of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter...

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Bibliographic Details
Main Author: Taylor, Frank E.
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:en_US
Published: American Physical Society 2015
Online Access:http://hdl.handle.net/1721.1/96375
https://orcid.org/0000-0002-7586-7253
Description
Summary:A search for excited states of the B[± over c] meson is performed using 4.9  fb[superscript −1] of 7 TeV and 19.2  fb[superscript −1] of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay B[± over c] → J/ψπ[superscript ±]. The state appears in the m(B[± over c]π[superscript +]π[superscript −]) − m(B[± over c]) − 2m(π[superscript ±]) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842 ± 4 ± 5  MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the B[± over c] meson, B[± over c](2S).