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Title: 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.
Authors:
; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
1816492
Publication Date:
NSF-PAR ID:
10108095
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
488
Issue:
1
Page Range or eLocation-ID:
559 to 571
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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