The Impact of the Environment of White Dwarf Mergers on Fast Radio Bursts

Abstract

Fast radio bursts (FRBs) are transient intense radio pulses with duration of milliseconds. Although the first FRB was detected more than a decade ago, the progenitors of these energetic events are not yet known. The currently preferred formation channel involves the formation of a neutron star (NS)/magnetar. While these objects are often the end product of the core-collapse (CC) explosion of massive stars, they could also be the outcome of the merging of two massive white dwarfs. In the merger scenario the ejected material interacts with a constant-density circumbinary medium and creates supersonic shocks. We found that when a radio pulse passes through these shocks the dispersion measure (DM) increases with time during the free expansion phase. The rotation measure (RM) displays a similar trend if the power-law index, $n$, of the outer part of the ejecta is $>6$. For $n=6$ the RM remains constant during this phase. Later, when the ejecta move into the Sedov-Taylor phase while the DM still increases, however, with a different rate, the RM reduces. This behaviour is somewhat similar to that of FRB 121102 for which a marginal increase of DM and a 10% decrease of RM have been observed over time. These features are in contrast to the CC scenario, where the DM and RM contributions to the radio signal always diminish with time.

10 pages, 3 figures, Accepted in MNRAS

References in corpus (21)

• A bright millisecond radio burst of extragalactic origin
• The direct localization of a fast radio burst and its host
• The Host Galaxy and Redshift of the Repeating Fast Radio Burst FRB 121102
• Fast Radio Burst Discovered in the Arecibo Pulsar ALFA Survey
• Fast radio bursts as synchrotron maser emission from decelerating relativistic blast waves
• A single fast radio burst localized to a massive galaxy at cosmological distance
• Circumstellar Emission from Type Ib and Ic Supernovae
• A fast radio burst localised to a massive galaxy
• The empirical metallicity dependence of the mass-loss rate of O- and early B-type stars
• Repeating Fast Radio Bursts from Magnetars with Low Magnetospheric Twist
• The prevalence of repeating fast radio bursts
• Magnetically-driven explosions of rapidly-rotating white dwarfs following Accretion-Induced Collapse
• The Australian Square Kilometre Array Pathfinder: Performance of the Boolardy Engineering Test Array
• Pulsar-wind nebulae and magnetar outflows: observations at radio, X-ray, and gamma-ray wavelengths
• Dispersion Measure Variation of Repeating Fast Radio Burst Sources
• Magnetic Field Generation in Stars
• Pre-Explosive Observational Properties of Type Ia Supernovae
• Constraining magnetic field amplification in SN shocks using radio observations of SNe 2011fe and 2014J
• Evolution of the progenitors of SNe 1993J and 2011dh revealed through late time radio and X-ray studies
• Heating from free-free absorption and the mass-loss rate of the progenitor stars to supernovae
• The environment of supernova remnant VRO 42.05.01 as probed with IRAM 30m molecular line observations

Cited by in corpus (5)

• Deep Synoptic Array science: A massive elliptical host among two galaxy-cluster fast radio bursts
• Dispersion and Rotation Measures from the Ejecta of Compact Binary Mergers: Clue to the Progenitors of Fast Radio Bursts
• Is FRB 191001 embedded in a supernova remnant?
• Free-free absorption in hot relativistic flows: application to fast radio bursts
• Radio Supernovae