The Galactic Halo Contribution to the Dispersion Measure of Extragalactic Fast Radio Bursts

Abstract

A new model of the Milky Way (MW) halo component of the dispersion measure (DM) for extragalactic sources, such as fast radio bursts (FRBs), is presented in light of recent diffuse X-ray observations. In addition to the spherical component of isothermal gas ($kT\sim 0.3$ keV) in hydrostatic equilibrium with the Galactic gravitational potential, our model includes a disk-like non-spherical hot gas component to reproduce the directional dependence of the observed X-ray emission measure (EM). The total gas mass ($1.2\times 10^{11}{M}_{\odot }$) is dominated by the spherical component, and is consistent with the total baryon mass of the MW expected from the dark matter mass and the cosmic baryon-to-dark-matter ratio. Our model predicts a mean halo DM of $43\mathrm{pc}\mathrm{c}{\mathrm{m}}^{-3}$, with a full range of $30$-$245\mathrm{pc}\mathrm{c}{\mathrm{m}}^{-3}$ over the whole sky. The large scatter seen in the X-ray EM data implies a $\sim 0.2$ dex (rms) fluctuation of the MW halo DM. We provide an analytic formula to estimate the MW halo DM of our model along any line of sight, which can be easily used to compute the total MW component of DM toward extragalactic sources, in combination with existing DM models of the warm ionized medium associated with the Galactic disk.

11 pages, 9 figures, 1 table, 2 hot gas halo components, accepted for publication in ApJ; v2

References in corpus (25)

• A bright millisecond radio burst of extragalactic origin
• A New Electron Density Model for Estimation of Pulsar and FRB Distances
• The direct localization of a fast radio burst and its host
• The Host Galaxy and Redshift of the Repeating Fast Radio Burst FRB 121102
• An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent
• A single fast radio burst localized to a massive galaxy at cosmological distance
• CHIME/FRB Detection of Eight New Repeating Fast Radio Burst Sources
• The Search for the Missing Baryons at Low Redshift
• A fast radio burst localised to a massive galaxy
• The Vertical Structure of Warm Ionised Gas in the Milky Way
• Constraining the Milky Way's Hot Gas Halo with OVII and OVII Emission Lines
• Probing Galactic Halos with Fast Radio Bursts
• Do Hot Haloes Around Galaxies Contain the Missing Baryons?
• X-Ray Absorption from the Milky Way Halo and the Local Group
• Where are the ``Missing'' Galactic Baryons?
• Faint Repetitions from a Bright Fast Radio Burst Source
• Discovery of 14 radio pulsars in a survey of the Magellanic Clouds
• The distribution of gas in the Local Group from constrained cosmological simulations: the case for Andromeda and the Milky Way galaxies
• XMM-Newton Survey of Local O VII Absorption Lines in the Spectra of Active Galactic Nuclei
• X-ray and UV spectroscopy of Galactic diffuse hot gas along the LMC X--3 sight line
• Cosmology-independent estimate of the fraction of baryon mass in the IGM from fast radio burst observations
• The Dispersion of Fast Radio Bursts from a Structured Intergalactic Medium at Redshifts z < 1.5
• Circumgalactic Oxygen Absorption and Feedback
• The Properties of the Galactic Hot Gaseous Halo from X-ray Emission
• The Astrophysical Consequences of Intervening Galaxy Gas on Fast Radio Bursts

Cited by in corpus (53)

• A repeating fast radio burst source in a globular cluster
• A nearby repeating fast radio burst in the direction of M81
• A Local Universe Host for the Repeating Fast Radio Burst FRB 20181030A
• Intergalactic medium dispersion measures of fast radio bursts estimated from IllustrisTNG simulation and their cosmological applications
• A comparison of Galactic electron density models using PyGEDM
• An FRB Sent Me a DM: Constraining the Electron Column of the Milky Way Halo with Fast Radio Burst Dispersion Measures from CHIME/FRB
• Energy functions of fast radio bursts derived from the first CHIME/FRB catalogue
• Redshift Estimation and Constraints on Intergalactic and Interstellar Media from Dispersion and Scattering of Fast Radio Bursts
• Exploring the dispersion measure of the Milky Way halo
• Constraining Galaxy Haloes from the Dispersion and Scattering of Fast Radio Bursts and Pulsars
• A Large Scale Magneto-ionic Fluctuation in the Local Environment of Periodic Fast Radio Burst Source, FRB 20180916B
• Finding the missing baryons in the intergalactic medium with localized fast radio bursts
• A bright, high rotation-measure FRB that skewers the M33 halo
• Revealing the Dynamic Magneto-ionic Environments of Repeating Fast Radio Burst Sources through Multi-year Polarimetric Monitoring with CHIME/FRB
• The hot circumgalactic medium of the Milky Way: evidence for super-virial, virial, and sub-virial temperature, non-solar chemical composition, and non-thermal line broadening
• Machine learning classification of CHIME fast radio bursts -- I. Supervised methods
• Machine learning classification of CHIME fast radio bursts: II. Unsupervised Methods
• Searching for Time-Dependent Axion Dark Matter Signals in Pulsars
• A Data-Driven Technique Using Millisecond Transients to Measure the Milky Way Halo
• What it Takes to Measure Reionization with Fast Radio Bursts
• Multiwavelength observations of Fast Radio Bursts
• Implications of CHIME repeating fast radio bursts
• The dispersion measure of Fast Radio Bursts host galaxies: estimation from cosmological simulations
• A fast radio burst localized at detection to an edge-on galaxy using very-long-baseline interferometry
• A sample of Fast Radio Bursts discovered and localised with MeerTRAP at the MeerKAT telescope
• LOFAR early-time search for coherent radio emission from Short GRB 181123B
• Radio Scattering Horizons for Galactic and Extragalactic Transients
• Exploring the Milky Way Circumgalactic Medium in a Cosmological Context with a Semi-Analytic Model
• Empirical estimates of the Galactic halo contribution to the dispersion measures of extragalactic fast radio bursts using X-ray absorption
• Birth and Evolution of Fast Radio Bursts: Strong Population-Based Evidence for a Neutron-Star Origin
• The Northern Cross Fast Radio Burst project -- III. The FRB-magnetar connection in a sample of nearby galaxies
• The Apertif Radio Transient System (ARTS): Design, Commissioning, Data Release, and Detection of the first 5 Fast Radio Bursts
• Constraining density and metallicity of the Milky Way's hot gas halo from O VII spectra and ram-pressure stripping
• Fast radio burst energy function in the presence of $\mathrm{D}{\mathrm{M}}_{\mathrm{host}}$ variation
• A method for reconstructing the Galactic magnetic field using dispersion of fast radio bursts and Faraday rotation of radio galaxies
• Reinvestigation of Fast Radio Burst Host Galaxy and Event Rate Density
• NE2025: An Updated Electron Density Model for the Galactic Interstellar Medium
• The dispersion measure and scattering of Fast Radio Bursts: contributions from multi-components, and clues for the intrinsic properties
• The AARTFAAC 60 MHz transients survey
• A Hyperactive FRB Pinpointed in an SMC-Like Satellite Host Galaxy
• Contemporaneous optical-radio observations of a fast radio burst in a close galaxy pair
• Redshift dependence of FRB host dispersion measures across cosmic epochs
• Perturbative and numerical approach to plasma strong lensing
• Constraining the Hubble constant with scattering in host galaxies of fast radio bursts
• Modeling the Cosmic Dispersion Measure in the D < 120 Mpc Local Universe
• On the relation between duration and energy of non-repeating fast radio bursts: census with the CHIME data
• Comprehensive analysis of the Apertif Fast Radio Burst sample: similarities with young, energetic neutron stars
• Comparative analysis of machine learning techniques for feature selection and classification of Fast Radio Bursts
• Refined Constraints on the Hubble Constant from Localized FRBs with Assessment of Systematic Effects
• Constraining the Milky Way's Dispersion Measure Using FRB and X-ray Data
• Redshift Distributions of Fast Radio Bursts Inferred Using Clustering in Dispersion Measure Space
• A Search for Low-frequency Radio Pulses from Long Gamma-ray Bursts with the Murchison Widefield Array
• Physics beyond the Standard Model with the DSA-2000