Transient Emissions from Radio-Active Stars: Implications for Wide-Field Radio Surveys

Abstract

Variability is a common characteristic of magnetically active stars. Flaring variability is usually interpreted as the observable consequence of transient magnetic reconnection processes happening in the stellar outer atmosphere. Stellar flares have been observed now across 11 decades in wavelength/frequency/energy; such a large span implies that a range of physical processes takes place during such events. Despite the fact that stellar radio flares have long been recognized and studied, key unanswered questions remain. I will highlight what, in my opinion, are some of these questions. I will also describe recent results on stellar flare emissions at radio wavelengths, discussing the nature of coherent and incoherent emissions and the prospects of wide-field radio imaging telescopes for studying such events.

10 pages, 2 figures. Invited refereed review from conference "Bursts, Pulses and Flickering: Wide-field Monitoring of the Dynamic Radio Sky". Full resolution figures available from Proceedings of Science web site: http://www.pos.sissa.it/cgi-bin/reader/conf.cgi?confid=56

References in corpus (4)

• Periodic Bursts of Coherent Radio Emission from an Ultracool Dwarf
• Nonthermal Hard X-ray Emission and Iron Kalpha Emission from a Superflare on II Pegasi
• Meeting the Cool Neighbors X: Ultracool dwarfs from the 2MASS All-Sky Data Release
• The nature of the DLS fast transients

Cited by in corpus (4)

• MKT J170456.2-482100: the first transient discovered by MeerKAT
• A Search for the Near-Infrared Counterpart to GCRT J1745-3009
• Radio Variable and Transient Sources on Minute Timescales in the ASKAP Pilot Surveys
• On the use of variability time-scales as an early classifier of radio transients and variables