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The population of M dwarfs observed at low radio frequencies
(2021-10-11)
Coherent low-frequency (≲200 MHz) radio emission from stars encodes the conditions of the outer corona, mass-ejection events and space weather 1–5. Previous low-frequency searches for radio-emitting stellar systems have ...
The LOFAR Two-metre Sky Survey Deep fields: : The star formation rate - radio luminosity relation at low frequencies
(2021-04-07)
In this paper, we investigate the relationship between 150 MHz luminosity and the star-formation rate - the SFR-L150 MHz relation - using 150 MHz measurements for a near-infrared selected sample of 118 517 z < 1 galaxies. ...
Radio galaxies and feedback from AGN jets
(2020-07-31)
We review current understanding of the population of radio galaxies and radio-loud quasars from an observational perspective, focusing on their large-scale structures and dynamics. We discuss the physical conditions in ...
Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388
(2020-06-05)
Context. Restarted radio galaxies represent a unique tool for investigating the duty cycle of the jet activity in active galactic nuclei (AGN). The radio galaxy 3C388 has long been claimed to be a peculiar example of an ...
Coherent radio emission from a quiescent red dwarf indicative of star-planet interaction
(2020-02-17)
Low-frequency (ν ≲ 150 MHz) stellar radio emission is expected to originate in the outer corona at heights comparable to and larger than the stellar radius. Such emission from the Sun has been used to study coronal structure, ...
Revisiting the Fanaroff-Riley dichotomy and radio-galaxy morphology with the LOFAR Two-Metre Sky Survey (LoTSS)
(2019-09-01)
The relative positions of the high and low surface brightness regions of radio-loud active galaxies in the 3CR sample were found by Fanaroff and Riley to be correlated with their luminosity. We revisit this canonical ...
The linear bias of radio galaxies at z~0.3 via cosmic microwave background lensing
(2019-02-26)
We present a new measurement of the linear bias of radio loud active galactic nuclei (RLAGN) at $z\approx0.3$ and $L_{\rm 1.4GHz}>10^{23}\,{\rm W\,Hz^{-1}}$ selected from the Best & Heckman (2012) sample, made by ...
Untangling cosmic magnetic fields: Faraday tomography at metre wavelengths with LOFAR
(2018-11-29)
The technique of Faraday tomography is a key tool for the study ofmagnetised plasmas in the new era of broadband radio-polarisation observations. In particular, observations at metre wavelengths provide significantly better ...
Focusing on the extended X-ray emission in 3C 459 with a Chandra follow-up observation
(2018-11-09)
Aims. We investigated the X-ray emission properties of the powerful radio galaxy 3C 459 revealed by a recent Chandra follow-up observation carried out in October 2014 with a 62 ks exposure. Methods. We performed an X-ray ...
LOFAR MSSS: Flattening low-frequency radio continuum spectra of nearby galaxies
(2018-11-07)
Aims. The shape of low-frequency radio continuum spectra of normal galaxies is not well understood, the key question being the role of physical processes such as thermal absorption in shaping them. In this work we take ...