ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti
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.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2019
- DOI:
- 10.1093/mnras/stz1684
- arXiv:
- arXiv:1906.06570
- Bibcode:
- 2019MNRAS.488..559Z
- Keywords:
-
- polarization;
- radiation mechanisms: non-thermal;
- stars: flare;
- stars: low-mass;
- stars: magnetic fields;
- radio continuum: stars;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 15 pages, 8 figures, 1 table. Accepted for publication in Monthly Notices of the Royal Astronomical Society