A HyperFlash and ÉCLAT view of the local environment and energetics of the repeating FRB 20240619D
Artikel i vetenskaplig tidskrift, 2026

Time-variable propagation effects provide a window into the local plasma environments of repeating fast radio burst (FRB) sources. Here we report high-cadence observations of FRB 20240619D, as part of the HyperFlash and ÉCLAT programmes. We observed for 500h and detected 217 bursts, including 10 bursts with high fluence ($>25$Jy ms) and implied energy. We track burst-to-burst variations in dispersion measure (DM) and rotation measure (RM), from which we constrain the parallel magnetic field strength in the source’s local environment: $0.27\pm 0.13$mG. Apparent DM variations between sub-bursts in a single bright event are interpreted as coming from plasma lensing or variable emission height. We also identify two distinct scintillation screens along the line of sight, one associated with the Milky Way and the other likely located in the FRB’s host galaxy or local environment. Together, these (time-variable) propagation effects reveal that FRB 20240619D is embedded in a dense, turbulent and highly magnetised plasma. The source’s environment is more dynamic than that measured for many other (repeating) FRB sources, but less extreme compared to several repeaters that are associated with a compact, persistent radio source. FRB 20240619D’s cumulative burst fluence distribution shows a power-law break, with a flat tail at high energies. Along with previous studies, this emphasises a common feature in the burst energy distribution of hyperactive repeaters. Using the break in the burst fluence distribution, we estimate a source redshift of $z=0.042-0.240$. We discuss FRB 20240619D’s nature in the context of similar studies of other repeating FRBs.

radio continuum: transients

fast radio bursts

Författare

O. S. Ould-Boukattine

Anton Pannekoek Institute for Astronomy

Netherlands Institute for Radio Astronomy (ASTRON)

A. J. Cooper

University of Oxford

J. W. T. Hessels

McGill University

Netherlands Institute for Radio Astronomy (ASTRON)

Anton Pannekoek Institute for Astronomy

Danté M. Hewitt

Anton Pannekoek Institute for Astronomy

S. K. Ocker

Carnegie Institution of Washington

California Institute of Technology (Caltech)

A. Moroianu

Anton Pannekoek Institute for Astronomy

K. Nimmo

Massachusetts Institute of Technology (MIT)

M. P. Snelders

Anton Pannekoek Institute for Astronomy

Netherlands Institute for Radio Astronomy (ASTRON)

I. Cognard

Station de Radioastronomie de Nançay

Laboratoire de Physique et de Chimie de l'Environnement et de l'Espace (LPC2E)

T. J. Dijkema

CAMRAS Dwingeloo Radio Telescope Foundation

Netherlands Institute for Radio Astronomy (ASTRON)

M. Fine

McGill University

Anton Pannekoek Institute for Astronomy

M. P. Gawroński

Uniwersytet Mikolaja Kopernika

W. Herrmann

Astropeiler Stockert e.V.

Jeff Huang

McGill University

Franz Kirsten

Netherlands Institute for Radio Astronomy (ASTRON)

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Z. Pleunis

Anton Pannekoek Institute for Astronomy

Netherlands Institute for Radio Astronomy (ASTRON)

W. Puchalska

Uniwersytet Mikolaja Kopernika

S. Ranguin

Anton Pannekoek Institute for Astronomy

T. Telkamp

CAMRAS Dwingeloo Radio Telescope Foundation

Monthly Notices of the Royal Astronomical Society

00358711 (ISSN) 13652966 (eISSN)

Vol. 546 3 stag090

Ämneskategorier (SSIF 2025)

Astronomi, astrofysik och kosmologi

DOI

10.1093/mnras/stag090

Mer information

Senast uppdaterat

2026-02-20