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arXiv · 1509.00476

Probing MeV to 90 GeV axion-like particles with LEP and LHC

Joerg Jaeckel·Michael Spannowsky
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Abstract

Axion-like particles (ALPs), relatively light (pseudo-)scalars coupled to two gauge bosons, are a common feature of many extensions of the Standard Model. Up to now there has been a gap in the sensitivity to such particles in the MeV to 10 GeV range. In this note we show that LEP data on $Z\toγγ$ decays provides significant constraints in this range (and indeed up to the $Z$-mass). We also discuss the sensitivities of LHC and future colliders. Particularly the LHC shows promising sensitivity in searching for a pseudo-scalar with $4 \lesssim m_a \lesssim 60$ GeV in the channel $pp \to 3 γ$ with $m_{3γ}\approx m_{Z}$.

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Joerg Jaeckel, Michael Spannowsky. 2015-09-01. Probing MeV to 90 GeV axion-like particles with LEP and LHC. https://doi.org/10.1016/j.physletb.2015.12.037

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