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

• Main Authors: de Boer, F. W. N, Fields, C. A
• Format: Journal Article
• Language: English
• Published: 16-03-2011
• Subjects: Physics - High Energy Physics - Phenomenology; Physics - Nuclear Experiment
• DOI: 10.48550/arxiv.1001.3897

Int. J. mod. Phys. E 20 (2011) 1787-1803 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.