Impulsive radio events in quiet solar corona and axion quark nugget dark matter

Abstract

The Murchison Widefield Array (MWA) recorded impulsive radio events in the quiet solar corona at frequencies 98, 120, 132, and 160 MHz [S. Mondal, D. Oberoi, and A. Mohan, Astrophys. J. 895, L39 (2020)]. We propose that these radio events are the direct manifestation of dark matter annihilation events within the axion quark nugget (AQN) framework. It has been argued [A. Zhitnitsky, J. Cosmol. Astropart. Phys. 10 (2017) 050; N. Raza, L. vanWaerbeke, and A. Zhitnitsky, Phys. Rev. D 98, 103527 (2018)] that the AQN-annihilation events in the quiet solar corona can be identified with the nanoflares conjectured by Parker [Astrophys. J. 264, 642 (1983)]. We further support this claim by demonstrating that observed impulsive radio events [S. Mondal, D. Oberoi, and A. Mohan, Astrophys. J. 895, L39 (2020)], including their rate of appearance, their temporal and spatial distributions, and their energetics, are matching the generic consequences of AQN annihilations in the quiet corona. We propose to test this idea by analyzing the correlated clustering of impulsive radio events in different frequency bands. These correlations are expressed in terms of the time delays between radio events in different frequency bands measured in seconds. We also make generic predictions for low (80 and 89 MHz) and high (179, 196, 217, and 240 MHz) frequency bands, that have been recorded, but not published, by Mondal et al. [Astrophys. J. 895, L392020]. We finally suggest to test our proposal by studying possible cross-correlation between MWA radio signals and Solar Orbiter recording of extreme UV photons (aka ``campfires'').