Searcharxiv⌕ Search

arXiv · 2610.27489

Constraining the FRB Central Engine from Flux Variations of Persistent Radio Sources: FRB 20240114A as the First Attempt

Abstract

Some repeating fast radio bursts (FRBs) are associated with persistent radio sources (PRSs), likely driven by the long-term activity of a central engine. We investigate FRB 20240114A-currently the most active repeating FRB-to explore the link between its burst activity and the flux variability of its associated PRS. We model electrons responsible for FRB emission being continuously injected from a central magnetar into its magnetar wind nebula (MWN), where synchrotron radiation produces the PRS. Comparing our model with the latest PRS spectra and flux variations, we constrain the physical properties of the FRB source. We find that the total energy injected into the MWN during FAST observations from January to August 2024 is $\sim 10^{48} \, \rm{erg}$, consistent with the magnetic energy budget of a magnetar with an internal magnetic field of $\sim 10^{16} \, \rm G$. The bulk Lorentz factor of the FRB-emitting plasma is mildly constrained to $\lesssim 10^3$, and FRB 20240114A is inferred to be powered by a young magnetar aged $\sim 10$-$20 \, \rm {yr}$. These results show that the PRS flux variability effectively probes FRB emission properties. We predict that while PRS luminosity increases rapidly with enhanced FRB activity, it will slowly fade over decades via adiabatic cooling after FRB activity ceases. Energetics suggest that the hyper-active phase observed in FRB 20240114A (burst rate $\sim 700 \, \rm hr^{-1}$) is a rare state with a duty cycle of $\lesssim 10^{-2}$, which is broadly consistent with its detection rate in current FRB-PRS samples.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Hirotaka Matsumiya, Kazumi Kashiyama, Tomonori Totani. 2026-10-20. Constraining the FRB Central Engine from Flux Variations of Persistent Radio Sources: FRB 20240114A as the First Attempt. https://arxiv.org/abs/2610.27489

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Double Neutron Star Mergers and Fast Blue Optical Transients: A Circumbinary Disk Connection

Post-common-envelope evolution (CEE) circumbinary disks (CBDs) form when part of the ejected envelope remains bound and circularizes around the stripped core and its companion. Leveraging results of scale-free hydrodynamical simulations, we develop a framework to model the effect of such disks on subsequent binary evolution, and implement it in the population synthesis code COMPAS. Applying our framework to double neutron star (DNS) merger progenitors, we find that CBDs generally induce substantial orbital shrinkage, changing the merging DNS population and lowering the overall merger rate. We explore an extensive grid of binary-evolution and disk models, and find that CBD interactions reduce the DNS merger rate by up to $28\%$, primarily through 'premature' mergers between the neutron star (NS) and the giant's core. These mergers may power luminous fast blue optical transients (LFBOTs), occurring at a fiducial rate of $\simeq11 \:\rm Gpc^{-3} \rm yr^{-1}$. Our results indicate that natal kicks contribute little to LFBOT offsets, and that they should be associated with young stellar populations, though not necessarily active star-forming regions. Since LFBOT progenitors would otherwise produce short-delay DNS mergers, CBDs further challenge DNS mergers as the source of early r-process enrichment. For surviving DNS mergers, accretion from the disk leads to higher chirp masses, potentially explaining the puzzling mass of GW190425. Our framework provides a general tool for studying CBD-binary interactions in post-CEE systems.

astro-ph.HE↗

High precision timing of seven binary millisecond pulsars with the European Pulsar Timing Array

Binary millisecond pulsars (MSPs) serve as exceptional astrophysical laboratories for a wide range of astrophysical studies, all of which rely on precise property measurements allowed by pulsar timing. In this paper, we present high-precision timing solutions for seven binary MSPs monitored by the European Pulsar Timing Array. By combining data collected from the five largest radio telescopes in Europe, as well as their coherently combined form, the Large European Array for Pulsars, we achieve phase-coherent timing solutions for all seven pulsars. We conduct a Bayesian timing and noise analysis on the combined data, yielding measurements of astrometric and orbital parameters with broadly improved precision, some reported for the first time. For PSRs J0125-2327, J1741+1351 and J2043+1711, we determine their distances and transverse velocities from astrometric measurements, and infer their masses via Shapiro delay measurements. Additionally, we examine the various contributions to the secular orbital-period variations for PSRs J0125-2327, J1125+7819 and J1741+1351, and estimate their kinematic distances. For PSRs J0125-2327 and J1741+1351, we detect the signature of annual-orbital parallax in the timing data. This allows us to derive a strongly favored, unique solution for the orbital ascending node and inclination angle for PSR J0125-2327, and a tightly constrained ascending node for PSR J1741+1351. Moreover, we use the orbital periods and their derivatives for several binary MSPs to place upper limits on gravitational-wave strain in both the sub-nanohertz and microhertz frequency regimes. Our results show that the orbits of binary MSPs could provide stringent constraints in microhertz range, thereby possibly complementing standard pulsar-timing-array analyses in the future.

astro-ph.HE↗

The Influence of the Inclination of the Accretion Disk in Black Hole X-Ray Binaries on the Energy Spectrum Characteristics

During the ascending and descending phases of some black hole X-ray binaries(BH XRBs), it was found that the X-ray Eddington ratio ($ L_{X-ray(3-25keV)}/L_{Edd} $) and the photon spectral index $Γ$ had an anticorrelation when the X-ray Eddington ratio was less than a specific value, and a positive correlation when it was greater than that value. Moreover, the cross points of the anticorrelation and positive correlation are different for different BH XRBs ($ L_{X-ray(3-25keV)}/L_{Edd} $ of cross point is between $ 0.1 \% $ and $ 10\% $). The reason why the cross points are different for different BH XRBs were still uncertain. So we processed the light curve and energy spectrum of 15 outbursts of eight BH XRBs during their descending phases. We found that for the same BH XRB, the values of the X-ray Eddington ratio at the cross point are basically consistent for different outburst times. However, for different BH XRBs, there is a positive linear correlation between the X-ray Eddington ratio at the cross point and the cosine of the accretion disk inclination. Therefore, We think that the geometric effect of the inclination has a significant impact on the evolution of the energy spectrum of the BH XRBs.

astro-ph.HE↗