Related papers: NE2025: An Updated Electron Density Model for the …
As the brightest galaxy cluster in the X-ray sky, Perseus is an excellent target for studying the Intracluster Medium (ICM), but until recently, its active galactic nucleus (AGN) made studies of the diffuse emission near its center nearly…
Most of the celestial gamma rays detected by the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope originate from the interstellar medium when energetic cosmic rays interact with interstellar nucleons and photons.…
We investigate the feasibility of detecting and probing various components of the ionized intergalactic medium (IGM) and their turbulent properties at radio frequencies through observations of scatter broadening of compact sources. There is…
The turbulent ionized interstellar medium diffracts radio waves and makes them propagate in multiple paths. The pulse-broadening observed at low frequencies results from the scattering effect of interstellar clouds of ionized gas. During…
Most observational studies of galactic-scale magnetic fields using Faraday rotation rely on estimates of thermal electron densities in galaxies and their radial variations. However, the spatial distribution of electrons in the interstellar…
Low-frequency radio observations of diffuse synchrotron radiation offer a unique vantage point for investigating the intricate relationship between gas and magnetic fields in the formation of structures within the Galaxy, spanning from the…
The Galactic interstellar turbulence affects the density distribution and star formation. We introduce a new method of measuring interstellar turbulent density spectra by using the dispersion measures (DMs) of a large sample of pulsars.…
The scattering diameters of Sgr A* and several nearby OH masers (~ 1" at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center. We combine radio-wave scattering data and free-free emission…
Recent MeerKAT radio continuum observations of the Galactic center at 20 cm show a large population of nonthermal radio filaments (NRFs) in the inner few hundred pc of the Galaxy. We have selected a sample of 57 radios ources, mainly…
Radio pulsars emit regular bursts of radio radiation that propagate through the interstellar medium (ISM), the tenuous gas and plasma between the stars. Previously known dispersive properties of the ISM cause low frequency pulses to be…
Over the past two years, we used a series of GBT observations to uncover at least 33 millisecond pulsars in the globular cluster Terzan 5 located in the Galactic bulge. We now have 32 timing solutions for the pulsars which give us precise…
Radio-wave scattering is enhanced dramatically for Galactic center sources in a region with radius >~ 15 arc min. Using scattering from Sgr A* and other sources, we show that pulse broadening for pulsars in the Galactic center is {\em at…
The electron density (${n_{\rm e}}$) of the interstellar medium (ISM) in star-forming galaxies is intimately linked to star formation and ionization condition. Using the high-resolution spectra obtained from the JWST NIRSpec micro shutter…
(abridged) Planck has observed the entire sky from 30 GHz to 857GHz. The observed foreground emission contains contributions from different phases of the interstellar medium (ISM). We have separated the observed Galactic emission into the…
We present an improved Global Sky Model (GSM) of diffuse galactic radio emission from 10 MHz to 5 THz, whose uses include foreground modeling for CMB and 21 cm cosmology. Our model improves on past work both algorithmically and by adding…
The combination of dispersion measures of pulsars, distances from the model of Cordes and Lazio (2002) and emission measures from the WHAM survey enabled a statistical study of electron densities and filling factors of the diffuse ionized…
Intergalactic scintillation of distant quasars is sensitive to free electrons and therefore complements Ly$\alpha$ absorption line experiments probing the neutral intergalactic medium (IGM). We present a new scheme to compute IGM refractive…
In this investigation, we present an analysis of the metallicity distribution that pertains to neutral gas in the local Galactic interstellar medium (ISM). We derive relative ISM metallicities for a sample of 84 sight lines probing diffuse…
Galaxy and occupies perhaps a quarter of the volume of the Galactic disk. Decoding the spectrum of the Galactic diffuse ionizing field is of fundamental interest. This can be done via direct measurements of ionization fractions of various…
Ever since the discovery of Cosmic Rays (CRs), significant advancements have been made in modeling their propagation in the Galaxy and in the Heliosphere. However, propagation models suffer from degeneracy of many parameters. To complicate…