Using SKA-Low to Detect PeV Gamma-rays from Galactic Sources

Anna Nelles; Philipp Laub; Haoning He; Felix Schlüter; Sjoerd Bouma; Justin Bray; Stijn Buitink; Arthur Corstanje; Vital De Henau; Edwin Dickinson; Brian Hare; Jörg Hörandel; Tim Huege; Clancy James; Xingyu Li; Hermann-Josef Mathes; Katharine Mulrey; Subhadip Saha; Olaf Scholten; Ralph Spencer; Christopher Sterpka; Karen Terveer; Satyendra Thoudam; Gia Trinh; Paulina Turekova; Darko Veberic; Keito Watanabe; Hiroaki Yamamoto; Chao Zhang; Pengfei Zhang; Yi Zhang

arXiv · 2606.25932

Using SKA-Low to Detect PeV Gamma-rays from Galactic Sources

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Abstract

Detecting so called PeVatrons is considered one of the prime goals of $\gamma$-ray astronomy. PeVatrons are astrophysical objects in the Galaxy that are sources of cosmic rays exceeding PeV ($10^{15}$ eV) energies, the highest in our Galaxy. Their nature is unknown as of now, with some candidates reaching barely above PeV energies just having been identified. Serendipitously, the energy threshold of air shower detection using radio emission, has been proven at 50 PeV. There is a case to be made that SKA-Low with its unprecedented number of antennas, can reach lower in energy, while the size of the core is sufficiently large provide a significant effective area to measure PeV fluxes. While this promises a novel angle towards understanding the cosmic ray accelerators in our Galaxy, it also would be the first detection of $\gamma$-ray air showers using radio emission.

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Anna Nelles, Philipp Laub, Haoning He, Felix Schlüter, Sjoerd Bouma, Justin Bray, Stijn Buitink, Arthur Corstanje, Vital De Henau, Edwin Dickinson, Brian Hare, Jörg Hörandel, Tim Huege, Clancy James, Xingyu Li, Hermann-Josef Mathes, Katharine Mulrey, Subhadip Saha, Olaf Scholten, Ralph Spencer, Christopher Sterpka, Karen Terveer, Satyendra Thoudam, Gia Trinh, Paulina Turekova, Darko Veberic, Keito Watanabe, Hiroaki Yamamoto, Chao Zhang, Pengfei Zhang, Yi Zhang. 2026-06-24. Using SKA-Low to Detect PeV Gamma-rays from Galactic Sources. https://arxiv.org/abs/2606.25932

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