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arXiv · 2102.10596

Connecting multi-lepton anomalies at the LHC and in Astrophysics with MeerKAT/SKA

Geoff Beck·Ralekete Temo·Elias Malwa·Mukesh Kumar·Bruce Mellado
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Abstract

Multi-lepton anomalies at the Large Hadron Collider (LHC) are reasonably well described by a two Higgs doublet model with an additional singlet scalar. Here, we demonstrate that using this model with parameters set by the LHC, we are also able to describe the excesses in gamma-ray flux from the galactic centre and the cosmic-ray spectra from AMS-02. This is achieved through Dark Matter (DM) annihilation via the singlet scalar. Of great interest is the flux of synchrotron emissions which results from annihilation of DM in Milky-Way satellites. We make predictions for MeerKAT/SKA observations of the nearby dwarf galaxy Reticulum II and we demonstrate the power of this instrument as a new frontier in indirect dark matter searches. Since the dark matter sector of the aforementioned two Higgs doublet model is unconstrained by current LHC data, we also demonstrate a synergy between particle and astrophysical searches in order to motivate further exploration of this promising model.

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Geoff Beck, Ralekete Temo, Elias Malwa, Mukesh Kumar, Bruce Mellado. 2023-02-05. Connecting multi-lepton anomalies at the LHC and in Astrophysics with MeerKAT/SKA. https://doi.org/10.1016/j.astropartphys.2023.102821

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