English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Recently detected coherent low-frequency radio emission from M dwarf systemsshares phenomenological similarities with emission produced by magnetosphericprocesses from the gas giant planets of our Solar System. Such beamedelectron-cyclotron maser emission can be driven by a star-planet interaction ora breakdown in co-rotation between a rotating plasma disk and a stellarmagnetosphere. Both models suggest that the radio emission could be periodic.Here we present the longest low-frequency interferometric monitoring campaignof an M dwarf system, composed of twenty-one $\approx$8 hour epochs taken intwo series of observing blocks separated by a year. We achieved a totalon-source time of 6.5 days. We show that the M dwarf binary CR Draconis has alow-frequency 3$\sigma$ detection rate of 90$^{+5}_{-8}$% when a noise floor of$\approx$0.1 mJy is reached, with a median flux density of 0.92 mJy, consistentcircularly polarised handedness, and a median circularly polarised fraction of66%. We resolve three bright radio bursts in dynamic spectra, revealing thebrightest is elliptically polarised, confined to 4 MHz of bandwidth centred on170 MHz, and reaches a flux density of 205 mJy. The burst structure is mottled,indicating it consists of unresolved sub-bursts. Such a structure shares astriking resemblance with the low-frequency emission from Jupiter. We suggestthe near-constant detection of high brightness temperature,highly-circularly-polarised radiation that has a consistent circularpolarisation handedness implies the emission is produced via theelectron-cyclotron maser instability. Optical photometric data reveal thesystem has a rotation period of 1.984$\pm$0.003 days. We observe no periodicityin the radio data, but the sampling of our radio observations produces a windowfunction that would hide the near two-day signal.

Low-frequency monitoring of flare star binary CR Draconis: Long-term electron-cyclotron maser emission