Fast Radio Bursts Research Articles

Constraints on the progenitor models of fast radio bursts from population synthesis with the first CHIME/FRB catalog

Fast radio bursts (FRBs) are enigmatic extragalactic radio transients with unknown origins. We performed comprehensive Monte Carlo simulations based on the first CHIME/FRB catalog to test whether the FRB population tracks the cosmic star formation history directly or requires a delay. By fully considering CHIME’s complex selection effects and beam response, we find that the hypothesis that the FRB population tracks the SFH is not ruled out by the current data, although a small delay is preferred. This is consistent with the scenario in which young magnetars formed through core-collapse supernovae serve as the progenitors of FRBs. ) erg to be Gpc yr ), which is consistent with previous results. This high volumetric rate means the core-collapse magnetar scenario alone cannot fully account for the observed population. Further theoretical efforts are required to explore alternative or additional progenitor channels for FRBs.

Possible Multi-Band Afterglows of FRB 20171020A and Their Implications

Fast Radio Bursts (FRBs) are millisecond-duration radio transients of mysterious origin, with growing evidence linking at least some of them to magnetars. While FRBs are primarily observed in the radio band, their potential multi-wavelength afterglows remain largely unexplored. We investigate the possible afterglow of FRB 20171020A, a rare nearby and bright FRB localized in a galaxy at only 37 Mpc. Assuming that this source produces a future bright burst, we model the expected afterglow emission in the radio, optical, and X-ray bands under both uniform and wind-like ambient media, within the framework of the magnetar model. Our results show that the optical afterglow is the most promising for detection, but it fades rapidly and requires follow-up within a few hundred seconds post-burst. The radio afterglow may be detectable under favorable conditions in a dense stellar wind, whereas the X-ray counterpart is too faint for current telescopes. These findings suggest that rapid optical follow-up offers the best opportunity to detect the afterglow of the next bright burst from FRB 20171020A, providing unique insights into the progenitor and its environment. To assess observational feasibility, we estimate the event rate of nearby FRBs with sufficient energy to power detectable afterglows, finding a rate of ∼0.3 per year for CHIME surveys. Although this rate is low and the optical detection timescale is short, coordinated fast-response strategies using global telescope networks could significantly improve the chance of success. As more nearby FRBs are discovered, multi-wavelength observations will be essential in unveiling the physical nature of these enigmatic events.

Synchronous and Asynchronous X-Ray Monitoring of FRB 20190520B with the Chandra X-Ray Observatory

Abstract We report on X-ray limits on observations of FRB 20190520B during simultaneous observations with the Green Bank Telescope and the Chandra X-ray Observatory. FRB 20190520B is an outlier in the fast radio burst (FRB) population due to its excess source-local dispersion, its association with compact persistent radio emission, and its high line-of-sight magnetic field variability. One radio burst was detected during the overlapping observing time, and no X-ray emission was detected. We find line-of-sight density and burst duration limits on FRB 20190520B’s X-ray luminosity, interpreting the nondetection in the context of known X-ray populations that might serve as progenitors for FRB 20190520B. We place a direct limit on the presence of a massive black hole (MBH) in this system, limiting mass and the Eddington ratio λ E to M BH < 4.3 × 1 0 3 ( λ E − 1 ) M ⊙ (in a low-density line-of-sight limit) and M BH < 1.8 × 1 0 4 ( λ E − 1 ) M ⊙ (high-density limit). These limits are both inconsistent with the scenario derived by Anna-Thomas et al. in which the FRB is viewed through a MBH wind; however, the model is still allowed if the wind luminosity has an X-ray emission fraction of less than 8%. Our observations would have been sensitive to the brightest ∼15% of the ultraluminous X-ray source (ULX) population and the brightest flares from soft gamma-ray repeaters, but the nondetection is consistent with expectations for SGR 1806-20–like flares, most ULX hypernebula models, and X-ray binaries.

Measuring the Hubble constant using localized and nonlocalized fast radio bursts

The Hubble constant (H_0) is one of the most important parameters in the standard rm Λ CDM model. The measurements given by the main two methods show a gap larger than $4σ$, which is known as Hubble tension. Fast radio bursts (FRBs) are extragalactic pulses with durations of milliseconds. They can be used as cosmological probes. We constrain H_0 using localized and nonlocalized FRBs. We first used 108 localized FRBs to constrain H_0 using the probability distributions of and from the IllustrisTNG simulation. Then, we used a Monte Carlo sampling to calculate the pseudo-redshift distributions of 527 nonlocalized FRBs from CHIME observations. The 108 localized FRBs yield a constraint of which lies between the early- and late-time values. The constraint of H_0 from nonlocalized FRBs yields This result indicates that the uncertainty on the constraint of H_0 drops to ∼1% when the number of localized FRBs is increased to ∼500. These uncertainties only include the statistical error. The systematic errors are also discussed and play a dominant role in the current sample.

Decoding the cosmological baryonic fluctuations using localized fast radio bursts

The enigma of the missing baryons poses a prominent and unresolved problem in astronomy. Dispersion measures (DM) serve as a distinctive observable of fast radio bursts (FRBs). They quantify the electron column density along each line of sight and reveal the missing baryons that are described in the Macquart (DM-z) relation. The scatter of this relation is anticipated to be caused by the variation in the cosmic structure. This is not yet statistically confirmed, however. We present statistical evidence that the cosmological baryons fluctuate. We measured the foreground galaxy number densities around 14 and 13 localized FRBs with the WISE-PS1-STRM and WISE times SCOS photometric redshift galaxy catalog, respectively. The foreground galaxy number densities were determined through a comparison with measured random apertures with a radius of 1 Mpc. We found a positive correlation between the excess of DM that is contributed by the medium outside galaxies (DM_ cosmic) and the foreground galaxy number density. The correlation is strong and statistically significant, with median Pearson coefficients of 0.6 and 0.6 and median p-values of 0.012 and 0.032 for the galaxy catalogs, respectively, as calculated with Monte Carlo simulations. Our findings indicate that the baryonic matter density outside galaxies exceeds its cosmic average along the line of sight to regions with an excess galaxy density, but there are fewer baryons along the line of sight to low-density regions. This is statistical evidence that the ionized baryons fluctuate cosmologically on a characteristic scale of lesssim6 Mpc.

High-frequency Fast Radio Burst Search of Nearby Star-forming Galaxies M77 and M82

Abstract The astrophysical origins of fast radio bursts (FRBs) are still unknown, but magnetars are a strong candidate for producing at least some FRBs. To investigate the magnetar progenitor model, we conducted a deep search of M77 and M82, two nearby galaxies with high star formation rates that could potentially harbor large magnetar populations. Using one of the 34 m dishes in the Deep Space Network, we observed the two galaxies at 8.4 GHz for about 100 hr each. At this observing frequency, we are unaffected by the potentially extreme temporal broadening caused by multipath scattering in the turbulent inner regions of the galaxies. We do not detect any FRBs from either galaxy above a fluence detection threshold of F min = 1.3 Jy ms , which corresponds to an isotropic energy equivalent of E iso,min = 2.7 × 1 0 36 erg for M77 and E iso,min = 1.7 × 1 0 35 erg for M82. Based on the nondetections, we set a 95% upper limit to the 8.4 GHz burst rate of R 95 = 273 yr−1 and R 95 = 233 yr−1 for M77 and M82, respectively. By estimating the magnetar population in each galaxy, we set an upper limit to the burst rate per magnetar of r max ≈ 1 magnetar − 1 yr − 1 . Unlike previous searches of these galaxies at frequencies of ν ≲ 1.5 GHz, our results give a scattering-independent limit to the burst rate.

Cosmological Parameter Estimate from Persistent Radio Sources of Fast Radio Bursts

Abstract We introduce a novel method to constrain the Hubble constant (H 0) by combining fast radio bursts (FRBs) and their persistent radio sources (PRSs) through the observationally validated Yang relation, L ν ∝ ∣RM∣, which links PRS luminosity to the rotation measure of the associated FRB. Using a mock sample of PRSs, we demonstrate that the Yang relation can help to unravel the degeneracies among H 0, baryon density parameter Ω b , and baryon fraction in the intergalactic medium f IGM in the traditional approach of using dispersion measure only to perform cosmological analyses. Our method employs a two-stage Markov Chain Monte Carlo analysis to constrain H 0. Using the available data of six observed PRS systems, we obtain a preliminary constraint of H 0 = 75 ± 30 km s−1 Mpc−1. We briefly discuss possible refinements of the method by reducing residual degeneracies and systematic uncertainties using future data and physical modeling. Our results indicate that the Yang relation can potentially become a new probe for performing FRB cosmology.

A Neural Network Model for the Cosmic Dispersion Measure in the CAMELS Simulations

Abstract The probability distribution, p(DM) of cosmic dispersion measures (DM) measured in fast radio bursts (FRBs) encodes information about both cosmology and galaxy feedback. In this work, we study the effect of feedback parameters in the p(DM) calculated from the full Latin Hypercube of parameters sampled by the CAMELS hydrodynamical simulation suite, building a neural network (NN) model that performs well in emulating the effect of feedback on p(DM) at arbitrary redshifts at z ≤ 1. Using this NN model, we further study the parameter F ≡ σDM z1/2, which is commonly used to summarize the scatter on p(DM). We find that F does not depend monotonically on every feedback parameter; instead each feedback mechanism jointly influences the final feedback strength in non-trivial ways. Even the largest values of F that we find in our entire parameter space are small compared to the current constraints from observed FRB DMs by Baptista et al. 2024, pointing at the limitations of the CAMELS suite due to the small simulation box sizes. In the future, with larger box-sizes from CAMELS-like suites, similar models can be used to constrain the parameters governing galaxy feedback in the increasing observational samples of FRBs.

Gravitational lensing: towards combining the multi-messengers.

The next generation of gravitational wave (GW) detectors and electromagnetic telescopes are beckoning the onset of the multi-messenger era and the exciting science that lies ahead. Multi-messenger strong gravitational lensing will help probe some of the most important questions of the Universe in an unprecedented manner. In particular, understanding the nature of GW sources, the underlying physical processes and mechanisms that produce emissions well before or right until the time of the merger, their associations to the seemingly distinct populations of gamma-ray bursts, fast radio bursts and kilonovae. Not to mention the fact that multi-messenger lensing will offer unique probes of test of gravity models and constraints on cosmological parameters complementary to other probes. Enabling multi-messenger science calls for concerted follow-up efforts and the development of new and shared resources in the community.This article is part of the Theo Murphy meeting issue 'Multi-messenger gravitational lensing (Part 2)'.

Search for Fast Radio Bursts and Radio Pulsars from Pulsing Ultraluminous X-Ray Sources

Search for Fast Radio Bursts and Radio Pulsars from Pulsing Ultraluminous X-Ray Sources

Reconciling the Waiting Time Peaks Variations of Repeating FRBs with an Eccentric Neutron Star–White Dwarf Binary

Fast radio bursts (FRBs) are luminous radio transients with millisecond duration. For some active repeaters, such as FRBs 20121102A and 20201124A, more than a thousand bursts have been detected by the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The waiting time (WT) distributions of both repeaters, defined as the time intervals between adjacent (detected) bursts, exhibit a bimodal structure well-fitted by two log-normal functions. Notably, the time scales of the long-duration WT peaks for both repeaters show a decreasing trend over time. These similar burst features suggest that there may be a common physical mechanism for FRBs 20121102A and 20201124A. In this paper, we revisit the neutron star (NS)–white dwarf (WD) binary model with an eccentric orbit to account for the observed changes in the long-duration WT peaks. According to our model, the shortening of the WT peaks corresponds to the orbital period decay of the NS-WD binary. We consider two mass transfer modes, namely, stable and unstable mass transfer, to examine how the orbital period evolves. Our findings reveal distinct evolutionary pathways for the two repeaters: for FRB 20121102A, the NS-WD binary likely undergoes a combination of common envelope (CE) ejection and Roche lobe overflow, whereas for FRB 20201124A the system may experience multiple CE ejections. These findings warrant further validation through follow-up observations.

Lensed fast radio bursts as a probe of a time-varying gravitational potential induced by wave dark matter

Lensed fast radio bursts as a probe of a time-varying gravitational potential induced by wave dark matter

Quantifying the coincidence between gravitational waves and fast radio bursts from neutron star-black hole mergers

Quantifying the coincidence between gravitational waves and fast radio bursts from neutron star-black hole mergers

Measuring cosmic growth rate with CSST spectroscopic survey and fast radio burst

The cosmic growth rate, which is related to peculiar velocity and is a primary scientific objective of galaxy spectroscopic surveys, can be inferred from the Redshift Space Distortion effect and the kinetic Sunyaev–Zel’dovich (kSZ) effect. However, the reconstruction noise power spectrum of the radial velocity field in kSZ is significantly dependent on the measurement of the small-scale galaxy-electron power spectrum Pge. In this study, we thoroughly discuss the enhancement of cosmic growth rate measurements facilitated by Fast Radio Bursts (FRBs), which probe the electron density of the universe along their propagation paths to provide crucial additional information on Pge. Subsequently, we utilize future spectroscopic surveys from the Chinese Space Station Telescope and the CMB-S4 experiment, combined with FRB dispersion measures, to achieve precise measurements of the cosmic growth rate at redshifts zg=0.15,0.45,0.75. Employing Fisher matrix forecasting analysis, we anticipate that constraints on fσ8 will reach a precision of 0.1% with a sample size of 106 FRBs. Furthermore, we perform a global analysis using Markov Chain Monte Carlo methods to constrain key parameters of three distinct dark energy models and a modified gravity model based on cosmic growth rate measurements. The results demonstrate that these refined fσ8 measurements considerably enhance the constraints on relevant cosmological parameters compared to those obtained from Planck CMB data. As the number of observed FRBs increases, alongside more precise galaxy surveys and next-generation CMB observations, new opportunities will arise for constraining cosmological models using the kSZ effect and for developing novel cosmological applications of FRBs.

Simultaneous Multiwavelength Observations of the Repeating Fast Radio Burst FRB 20190520B with Swift and FAST

Abstract Among several dozen known repeating fast radio bursts, those precisely localized offer the best opportunities to explore their multiwavelength counterparts, which are key to uncovering their origins. Here we report our X-ray, ultraviolet (UV), and optical observations with the Swift satellite of the repeating FRB 20190520B, in coordination with simultaneous radio observations with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Our aim was to detect potentially associated multiwavelength bursts and identify any persistent multiwavelength counterparts to the associated persistent radio source (PRS). While a total of 10 radio bursts were detected by FAST during the Swift observations, we detected no X-ray, UV, or optical bursts in accompany with the radio bursts. We obtained the energy upper limits (3σ) on any multwavelength bursts as follows: 5.03 × 1047 erg in the hard X-ray band (15–150 keV), 7.98 × 1045 erg in the soft X-ray band (0.3–10 keV), and 4.51 × 1044 erg in the U band (3465 Å), respectively. The energy ratio between soft X-ray (0.3–10 keV) and radio emission of the bursts is constrained as <6 × 107, and the ratio between optical (U band) and radio as <1.19 × 106. We detect no multiwavelength counterpart to the PRS. The 3σ luminosity upper limits are 1.04 × 1047 (15–150 keV), 8.81 × 1042 (0.3–10 keV), 9.26 × 1042 (UVW1), and 2.54 × 1042 erg s−1 (U), respectively. We show that the PRS is much more radio-loud than representative pulsar wind nebulae, supernova remnants, extended jets of Galactic X-ray binaries, and ultraluminous X-ray sources, suggestive of boosted radio emission of the PRS.

Radiative cooling induced coherent maser emission in relativistic plasmas.

Relativistic plasmas in strong electromagnetic fields exhibit distinct properties compared to classical plasmas. In astrophysical environments, such as neutron stars, white dwarfs, active galactic nuclei, and shocks, relativistic plasmas are pervasive and are expected to play a crucial role in the dynamics of these systems. Despite their significance, experimental and theoretical studies of these plasmas have been limited. Here, we present the first ab initio high-resolution kinetic simulations of relativistic plasmas undergoing synchrotron cooling in a highly magnetized medium. Our results demonstrate that these plasmas spontaneously generate coherent linearly polarized radiation in a wide range of parameters via the electron cyclotron maser instability, with radiative losses altering the saturation mechanism. Thus, the plasma continuously amplify coherent radiation for substantially longer durations of time. These findings highlight fundamental differences in the behavior of relativistic plasmas in strongly magnetized environments and align with astronomical phenomena, such as pulsar emission and fast radio bursts.

Fast radio bursts and the radio perspective on multi-messenger gravitational lensing.

Fast radio bursts (FRBs) are extragalactic millisecond-duration radio transients whose nature remains unknown. The advent of numerous facilities conducting dedicated FRB searches has dramatically revolutionized the field: hundreds of new bursts have been detected, and some are now known to repeat. Using interferometry, it is now possible to localize FRBs to their host galaxies, opening up new avenues for using FRBs as astrophysical probes. One promising application is studying gravitationally lensed FRBs. This review outlines the requirements for identifying a lensed FRB, taking into account their propagation effects and the importance of capturing the amplitude and phase of the signal. It also explores the different lens masses that could be probed with FRBs throughout the duration of an FRB survey, from stellar masses to individual galaxies. This highlights the unique cosmological applications of gravitationally lensed FRBs, including measurements of the Hubble constant and the compact object content of dark matter. Finally, we discuss future radio interferometers and the prospects for finding gravitationally lensed FRBs.This article is part of the Theo Murphy meeting issue 'Multi-messenger gravitational lensing (Part 1)'.

AGILE Observations of a Sample of Repeating Fast Radio Burst Sources

Abstract Fast radio bursts (FRBs) are millisecond-duration bursts originating from distant sources. They are classified into two categories: non-repeating FRBs, which manifest as singular events, and repeater FRBs (R-FRBs), which emit multiple bursts over time. In this work, we report a search for X- and γ-ray counterparts to a selected sample of R-FRBs using data from the AGILE satellite. The sample focused on sources with an excess dispersion measure (DM) below 300 pc cm−3. The analysis focused on the bursts covered by AGILE Mini-Calorimeter (MCAL) high-resolution data. No astrophysical signals were identified, and we derived upper limits (ULs) on the flux above 400 keV for the associated sources, adopting a spectral magnetar model, one of the leading models for FRB emission. Moreover, for a single burst of FRB 20200120E we estimated the flux ULs from the SuperAGILE detector data in the 18–60 keV energy range. We also performed a check of the GRID coverage for each burst in the 0.03–10 GeV energy band on short timescales, from 10 to 103 s, and on longer ones including the complete ∼17 yr AGILE/GRID archive. We then considered the famous event FRB 200428 from the Galactic magnetar SGR 1935+2154 as a reference to extrapolate a possible X-ray emission in MCAL and SuperAGILE bands from the radio energies of R-FRBs using the E X/E radio of FRB 200428 as a fixed parameter. We compared these energies with historical magnetar X-ray bursts rescaled in the same bands. Our observations set useful constraints on the FRB magnetar model in particular, the MCAL ULs are currently the most stringent in the 0.4–30 MeV band.

The Extreme Faraday Effect in Fast Radio Bursts

Abstract Fast radio bursts (FRBs) are a type of highly polarized, millisecond-duration electromagnetic pulse in the radio band, which is mostly produced at cosmological distances. These properties provide a natural laboratory for testing the extreme Faraday effect, a phenomenon in which two different propagation modes of a pulse separate after passing through a dense, highly ionized, and magnetized medium. We derive the critical condition (e.g., rotation measure) for the extreme Faraday effect to occur in FRBs, which exceeds the currently observed maximum value but remains within the theoretically predicted range. Some new features of FRBs (in particular, radio bursts with much shorter durations) after undergoing the extreme Faraday effect are predicted, such as sudden sign reversals of circular polarization, conspicuous frequency drifting, and emergency of extremely high circular polarization degrees. A potential application of this effect in FRBs is that, by comparing morphological differences of the two separated twin modes, one can identify the variations of plasma properties over extremely short timescales along the propagation path. Therefore, if this effect is found with future observations, it would provide a new tool for probing dense, magnetized environments near FRB sources.

A Possible Four Month Periodicity in the Activity of FRB 20240209A

Abstract Fast radio bursts (FRBs) are millisecond-duration radio transients from distant galaxies. While most FRBs are singular events, repeaters emit multiple bursts, with only two—FRB 121102 and FRB 180916B—showing periodic activity (160 and 16 days, respectively). FRB 20240209A, discovered by CHIME-FRB, is localized to the outskirts of a quiescent elliptical galaxy (z = 0.1384). We discovered a periodicity of ∼126 days in the activity of the FRB 20240209A, potentially adding to the list of extremely rare periodic repeating FRBs. We used autocorrelation and Lomb–Scargle periodogram analyses, validated with randomized control samples, to confirm the periodicity. The FRB’s location in an old stellar population disfavors young progenitor models, instead pointing to scenarios involving globular clusters, late-stage magnetars, or low-mass X-ray binaries. Though deep X-ray or polarimetric observations are not available, the localization of the FRB and a possible periodicity point to progenitors likely to be a binary involving a compact object and a stellar companion or a precessing/rotating old neutron star.