A radio transient with unusually slow periodic emission

Abstract

The high-frequency radio sky is bursting with synchrotron transients from massive stellar explosions and accretion events, but the low-frequency radio sky has so far been quiet beyond the Galactic pulsar population and the long-term scintillation of AGN. The low-frequency band, however, is sensitive to exotic coherent and polarised radio emission processes such as electron cyclotron maser emission from flaring M-dwarfs [1], stellar magnetospheric plasma interactions with exoplanets [2], and a population of steep-spectrum pulsars [3], making Galactic plane searches a prospect for blind transient discovery. Here we report an analysis of archival low-frequency radio data that reveals a periodic, low-frequency radio transient. We find that the source pulses every 18.18 minutes, an unusual periodicity not previously observed. The emission is highly linearly polarised, bright, persists for 30--60 s on each occurrence, and is visible across a broad frequency range. At times the pulses comprise short ($<0.5$-s) duration bursts; at others, a smoother profile is observed. These profiles evolve on timescales of hours. By measuring the dispersion of the radio pulses with respect to frequency, we have localised the source to within our own Galaxy, and suggest that it could be an ultra-long period magnetar.

4 main figures, 9 extended figures

References in corpus (13)

• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• A radio pulsing white dwarf binary star
• Radio emission evolution, polarimetry and multifrequency single pulse analysis of the radio magnetar PSR J1622-4950
• The fundamental plane for radio magnetars
• Understanding Instrumental Stokes Leakage in Murchison Widefield Array Polarimetry
• The variability timescales and brightness temperatures of radio flares from stars to supermassive black holes
• The challenges of low-frequency radio polarimetry: lessons from the Murchison Widefield Array
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey II: Galactic Plane $345^{\circ }<l<67^{\circ }$, $180^{\circ }<l<240^{\circ }$
• 154 MHz detection of faint, polarized flares from UV Ceti
• Discovery of a steep-spectrum low-luminosity pulsar with the Murchison Widefield Array
• A GMRT 150 MHz Search for Variables and Transients in Stripe 82

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• The Northern High Time Resolution Universe pulsar survey: II. Single-pulse search set-up and simulations
• Electron Cyclotron Maser Emission as the Driving Mechanism in Long-Period Radio Transients
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• Identifying Long Radio Transients with Accompanying X-Ray Emission as Disk-Jet Precessing Black Holes: The Case of ASKAP J1832-0911
• A Target Search for Fast Radio Bursts Associated with Two Fast Blue Optical Transients: AT2018cow and CSS161010
• Spectral-line performance of low-frequency radio telescope arrays: SKA-Low stations
• 21 years of Astronomy at Warwick: celebrating the legacy of Prof. Tom Marsh
• Search of nearby resolved neutron stars among optical sources
• Deep Synoptic Array Science: Searching for Long Duration Radio Transients with the DSA-110
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