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arXiv · 1001.3897

A Re-evaluation of Evidence for Light Neutral Bosons in Nuclear Emulsions

F. W. N. de Boer·C. A. Fields
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Abstract

Electron-positron pair-production data obtained by bombardment of emulsion detectors with either cosmic rays or projectiles with mass between one and 207 and kinetic energies between 18 GeV and 32 TeV have been re-analysed using a consistent and conservative model of the background from electromagnetic pair conversion. The combined data yield a spectrum of putative neutral bosons decaying to e+e- pairs, with masses between 3 and 20 MeV/c^2 and femtosecond lifetimes. The statistical significance against background for these "X-bosons" varies between 2 and 8 sigma. The cross-section for direct production of X-bosons increases slowly with projectile energy, remaining over 1,000 times smaller the the pion production cross-section.

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F. W. N. de Boer, C. A. Fields. 2010-01-21. A Re-evaluation of Evidence for Light Neutral Bosons in Nuclear Emulsions. https://doi.org/10.1142/s021830131101960x

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