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Related papers: Simulating intergalactic quasar scintillation

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We present a study exploring the nature and properties of the Circum-Galactic Medium (CGM) and its connection to the atomic gas content in the interstellar medium (ISM) of galaxies as traced by the HI 21cm line. Our sample includes 45 low-z…

Cosmological simulations fail to reproduce realistic galaxy populations without energy injection from active galactic nuclei (AGN) into the interstellar medium (ISM) and circumgalactic medium (CGM); a process called `AGN feedback'.…

Astrophysics of Galaxies · Physics 2024-11-20 C. M. Harrison , A. Girdhar , S. R. Ward

High-redshift quasars (z >~ 6) drive ionization fronts into the intergalactic medium (IGM). If the thickness of the front can be measured, it can provide a novel constraint on the ionizing spectral energy distribution (SED). Here we follow…

Astrophysics · Physics 2008-01-10 Roban Hultman Kramer , Zoltán Haiman

Cosmic reionization was the last major phase transition of hydrogen from neutral to highly ionized in the intergalactic medium (IGM). Current observations show that the IGM is significantly neutral at $z>7$, and largely ionized by…

Using samples drawn from the Sloan Digital Sky Survey, we study for the first time the relation between large-scale environments (Clusters, Groups and Voids) and the stellar Initial Mass Function (IMF). We perform an observational approach…

Astrophysics of Galaxies · Physics 2019-04-29 Elham Eftekhari , Moein Mosleh , Alexandre Vazdekis , Saeed Tavasoli

A bright quasar residing in a dense and largely neutral intergalactic medium (IGM) at high redshifts (z > 6) will be surrounded by a large cosmological Stromgren sphere. The quasar's spectrum will then show a sharp increase in resonant…

Astrophysics · Physics 2009-11-10 Andrei Mesinger , Zoltan Haiman

The dispersion measure (DM) of fast radio bursts (FRBs) provides a unique way to probe ionised baryons in the intergalactic medium (IGM). Cosmological models with different parameters lead to different DM-redshift ($\mathrm{DM}-z$)…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 Adam J. Batten , Alan R. Duffy , Nastasha Wijers , Vivek Gupta , Chris Flynn , Joop Schaye , Emma Ryan-Weber

We investigate the possibility of constraining the ionization state of the intergalactic medium (IGM) close to the end of reionization (z ~ 6) by measuring the size of the HII regions in high-z quasars spectra. We perform a combination of…

Astrophysics · Physics 2008-11-26 A. Maselli , S. Gallerani , A. Ferrara , T. R. Choudhury

The discovery of giant quasar Ly$\alpha$ nebulae at $z>2$ has opened up the possibility to directly study in emission the Circumgalactic and Intergalactic Medium (CGM/IGM). However, the resonant nature of the Ly$\alpha$ line and its…

Pulsar scintillation can be used to measure small scale structure in the Galaxy, but little is known about the specific interstellar medium features that cause scintillation. We searched for interstellar medium counterparts to all…

High Energy Astrophysical Phenomena · Physics 2025-06-04 Ashley M. Stock , Marten H. van Kerkwijk

The radiation background produced by the 21 cm spin-flip transition of neutral hydrogen at high redshifts can be a pristine probe of fundamental physics and cosmology. At z~30-300, the intergalactic medium (IGM) is visible in 21 cm…

Astrophysics · Physics 2008-11-26 Steven Furlanetto , S. Peng Oh , Elena Pierpaoli

Corrections to the magnitudes of high redshift objects due to intergalactic attenuation are computed using current estimates of the properties of the intergalactic medium. The results of numerical simulations are used to estimate the…

Astrophysics · Physics 2007-05-23 Avery Meiksin

Numerical hydrodynamical simulations have proven a successful means of reproducing many of the statistical properties of the LyA forest as measured in high redshift (z > 4) quasar spectra. The source of ionization of the Intergalactic…

Astrophysics · Physics 2008-11-26 Avery Meiksin , Martin White

The distribution of the absorption line broadening observed in the Ly$\alpha$ forest carries information about the temperature and widths of the filaments in the intergalactic medium (IGM). In this work, we present and test a new method for…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-04 Antonella Garzilli , Tom Theuns , Joop Schaye

We use cosmological simulations to explore the large-scale effects of reionization. Since reionization is a process that involves a large dynamic range - from galaxies to rare bright quasars - we need to be able to cover a significant…

Astrophysics · Physics 2008-11-26 Katharina Kohler , Nickolay Y. Gnedin , Andrew J. S. Hamilton

We present a new model for the distribution of free electrons in the Galaxy, the Magellanic Clouds and the intergalactic medium (IGM) that can be used to estimate distances to real or simulated pulsars and fast radio bursts (FRBs) based on…

Astrophysics of Galaxies · Physics 2017-01-25 J. M. Yao , R. N. Manchester , N. Wang

We present a new calculation of the intergalactic gamma-ray absorption coefficient as a function of both energy and redshift. In reexamining this problem, we make use of a new, empirically based calculation (as opposed to previous model…

Astrophysics · Physics 2010-11-30 F. W. Stecker , O. C. De Jager

We propose a new method to detect off-pulse (unpulsed and/or continuous) emission from pulsars, using the intensity modulations associated with interstellar scintillation. Our technique involves obtaining the dynamic spectra, separately for…

High Energy Astrophysical Phenomena · Physics 2018-05-23 Kumar Ravi , Avinash A. Deshpande

We study three quasar radio sources (B1257-326, B1519-273, and J1819+385) that show large amplitude intraday and annual scintillation variability produced by the Earth's motion relative to turbulent-scattering screens located within a few…

Astrophysics · Physics 2009-11-13 Jeffrey L. Linsky , Barney J. Rickett , Seth Redfield

Pulsar scintillation allows a glimpse into small-scale plasma structures in the interstellar medium, if we can infer their properties from the scintillation pattern. With Very Long Baseline Interferometry and working in delay-delay rate…

Instrumentation and Methods for Astrophysics · Physics 2019-08-07 Dana Simard , Ue-Li Pen , Visweshwar Ram Marthi , Walter Brisken
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