ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti. Issue 1 (28th June 2019)

• Record Type: Journal Article
• Authors: Zic, Andrew; Stewart, Adam; Lenc, Emil; Murphy, Tara; Lynch, Christene; Kaplan, David L; Hotan, Aidan; Anderson, Craig; Bunton, John D; Chippendale, Aaron; Mader, Stacy; Phillips, Chris
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 488:Issue 1(2019)
• Page Start: 559
• Page End: 571
• Publication Date: 2019-06-28
• Subjects: polarization -- radiation mechanisms: non-thermal -- stars: flare -- stars: low-mass -- stars: magnetic fields -- radio continuum: stars; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz1684
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: Active M dwarfs are known to produce bursty radio emission, and multiwavelength studies have shown that solar-like magnetic activity occurs in these stars. However, coherent bursts from active M dwarfs have often been difficult to interpret in the solar activity paradigm. We present Australian Square Array Pathfinder (ASKAP) observations of UV Ceti at a central frequency of 888 MHz. We detect several periodic, coherent pulses occurring over a time-scale consistent with the rotational period of UV Ceti. The properties of the pulsed emission show that they originate from the electron cyclotron maser instability, in a cavity at least 7 orders of magnitude less dense than the mean coronal density at the estimated source altitude. These results confirm that auroral activity can occur in active M dwarfs, suggesting that these stars mark the beginning of the transition from solar-like to auroral magnetospheric behaviour. These results demonstrate the capabilities of ASKAP for detecting polarized, coherent bursts from active stars and other systems.