Limit on the production of a new vector boson in e+e− → Uγ, U → π+π− with the KLOE experiment
2016 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 757, 356-361 p.Article in journal (Refereed) PublishedText
Abstract The recent interest in a light gauge boson in the framework of an extra U(1) symmetry motivates searches in the mass range below 1 GeV. We present a search for such a particle, the dark photon, in e + e − → U γ , U → π + π − based on 28 million e + e − → π + π − γ events collected at DAΦNE by the KLOE experiment. The π + π − production by initial-state radiation compensates for a loss of sensitivity of previous KLOE U → e + e − , μ + μ − searches due to the small branching ratios in the ρ – ω resonance region. We found no evidence for a signal and set a limit at 90% CL on the mixing strength between the photon and the dark photon, ε 2 , in the U mass range between 527 and 987 MeV . Above 700 MeV this new limit is more stringent than previous ones.
Place, publisher, year, edition, pages
2016. Vol. 757, 356-361 p.
Dark matter, Dark forces, Dark photon, U boson
IdentifiersURN: urn:nbn:se:uu:diva-289366DOI: 10.1016/j.physletb.2016.04.019ISI: 000376800300048OAI: oai:DiVA.org:uu-289366DiVA: diva2:925043
FunderEU, European Research Council, RII3-CT-2004-506078EU, FP7, Seventh Framework Programme, 227431 FP7-INFRASTRUCTURES-2008-1