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arXiv · 2103.01862

Searching for axionlike particles with low masses in $pPb$ and $PbPb$ collisions

V. P. Goncalves·D. E. Martins·M. S. Rangel
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Abstract

The production of axionlike particles (ALPs) with small masses in ultraperipheral $Pb - p$ and $Pb - Pb$ collisions at the LHC is investigated. The cross section and kinematical distributions associated to the diphoton final state produced in the $\gamma \gamma \rightarrow a \rightarrow \gamma \gamma$ subprocesses are estimated considering a realistic set of kinematical cuts. A detailed analysis of the backgrounds is performed and the expected sensitivity to the ALP production is derived. Our results demonstrate that a future experimental analysis of the exclusive diphoton production for the forward rapidities probed by the LHCb detector can improve the existing exclusion limits on the ALP - photon coupling in the mass range 2 GeV $\le m_a \le$ 5 GeV.

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V. P. Goncalves, D. E. Martins, M. S. Rangel. 2021-03-02. Searching for axionlike particles with low masses in $pPb$ and $PbPb$ collisions. https://doi.org/10.1140/epjc%2Fs10052-021-09314-2

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