Abstract
We report the results of a search for the bottomonium ground state in the photon energy spectrum with a sample of million of recorded at the energy with the BABAR detector at the PEP-II factory at SLAC. We observe a peak in the photon energy spectrum at with a significance of 10 standard deviations. We interpret the observed peak as being due to monochromatic photons from the radiative transition . This photon energy corresponds to an mass of . The hyperfine - mass splitting is . The branching fraction for this radiative decay is estimated to be .
- Received 7 July 2008
DOI:https://doi.org/10.1103/PhysRevLett.101.071801
©2008 American Physical Society
Erratum
Erratum: Observation of the Bottomonium Ground State in the Decay [Phys. Rev. Lett. 101, 071801 (2008)]
B. Aubert et al. (BABAR Collaboration)
Phys. Rev. Lett. 102, 029901 (2009)
Viewpoint
Searching high and low for bottomonium
Published 11 August 2008
The BABAR collaboration at SLAC has observed the radiative decay of an excited state of bottomonium (the bound state of a bottom quark and its antiparticle) to its ground state . Observing this long-sought ground state should enable better tests of quantum chromodynamic calculations of quark interactions and the computational approach called lattice quantum chromodynamics.
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