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تسجيل مستخدم جديدDark matter annihilation in $omega$ Centauri: Astrophysical implications derived from the MWA radio data
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We present an analysis of Murchison Widefield Array radio telescope data from $omega$ Cen, possibly a stripped dwarf spheroidal galaxy core captured by our Galaxy. Recent interpretations of Fermi-LAT $gamma$-ray data by Brown {it et al.} (2019) and Reynoso-Cordova {it et al.} (2019) suggest that $omega$ Cen may contain significant Dark Matter. We utilise their best-fit Dark Matter annihilation models, and an estimate of the magnetic field strength in $omega$ Cen, to calculate the expected radio synchrotron signal from annihilation, and show that one can usefully rule out significant parts of the magnetic field - diffusion coefficient plane using our current observational limits on the radio emission. Improvement by a factor of 10-100 on these limits could constrain the models even more tightly.
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