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Related papers: Simulating intergalactic quasar scintillation

200 papers

We present a fitting function to describe the statistics of flux modulations caused by interstellar scintillation. The function models a very general quantity: the cross-correlation of the flux observed from a compact radio source of finite…

Astrophysics · Physics 2009-11-13 J. Goodman , R. Narayan

We examine a large set of synthetic quasar spectra to realistically assess the potential of using the relative sizes of highly ionized near-zones in the Lya and Lyb forest as a probe of the neutral hydrogen content of the intergalactic…

Astrophysics · Physics 2009-11-13 James S. Bolton , Martin G. Haehnelt

The circumgalactic medium (CGM) is poorly constrained at the sub-parsec scales relevant to turbulent energy dissipation and regulation of multi-phase structure. Fast radio bursts (FRBs) are sensitive to small-scale plasma density…

Astrophysics of Galaxies · Physics 2025-07-25 S. K. Ocker , M. Chen , S. P. Oh , P. Sharma

We present an argument for a {\it lower limit} to the Compton-$y$ parameter describing spectral distortions of the cosmic microwave background (CMB). The absence of a detectable Gunn-Peterson signal in the spectra of high redshift quasars…

Astrophysics · Physics 2015-06-24 J. G. Bartlett , D. Barbosa , A. Blanchard

The incorporation of radiative transfer effects into cosmological hydrodynamical simulations is essential for understanding how the intergalactic medium (IGM) makes the transition from a neutral medium to one that is almost fully ionized.…

Astrophysics · Physics 2009-11-06 Aaron Sokasian , Tom Abel , Lars E. Hernquist

We analyze a sample of 58 multi-wavelength, Very Long Baseline Array observations of active galactic nuclei (AGN) to determine their scattering properties. Approximately 75% of the sample consists of AGN that exhibit centimeter-wavelength…

Weak interstellar scintillations of pulsar B0809+74 were observed at two epochs using a 30m EISCAT antenna at 933 MHz. These have been used to constrain the spectrum, the distribution and the transverse velocity of the scattering plasma…

Astrophysics · Physics 2015-06-24 Barney Rickett , Bill Coles , Jussi Markkanen

Pulsar dispersion measures (DMs) have been used to model the electron density of the interstellar medium (ISM) in the Galactic disk as a plane-parallel medium, despite significant scatter in the DM-distance distribution and strong evidence…

Astrophysics of Galaxies · Physics 2020-07-10 Stella Koch Ocker , James M. Cordes , Shami Chatterjee

We investigate the precision with which the Lyman-$\alpha$ damping wing signature imprinted on the spectra of high-redshift quasars (QSOs) by the foreground neutral intergalactic medium (IGM) can measure the history of cosmic reionization.…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-19 Timo Kist , Joseph F. Hennawi , Frederick B. Davies

We re-examine scattering of photons near the Lyman-alpha resonance in the intergalactic medium (IGM). We first derive a general integral solution for the radiation field around resonance when spin diffusivity is ignored. Our solution shows…

Astrophysics · Physics 2009-11-11 Steven Furlanetto , Jonathan R. Pritchard

Ly$\alpha$ intensity mapping is emerging as a new probe of faint galaxies consisting the cosmic web that elude traditional surveys. However, the resonant nature of Ly$\alpha$ radiative transfer complicates the interpretation of observed…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-25 Hyunbae Park , Hyunmi Song , Chris Byrohl , Aaron Smith , Yajima Hidenobu , Zarija Lukić

The hot intracluster medium (ICM) provides a unique laboratory to test multi-scale physics in numerical simulations and probe plasma physics. Utilizing archival Chandra observations, we measure density fluctuations in the ICM in a sample of…

High Energy Astrophysical Phenomena · Physics 2024-01-30 Annie Heinrich , Irina Zhuravleva , Congyao Zhang , Eugene Churazov , William Forman , Reinout J. van Weeren

Recently Menard et al. detected a subtle but systematic change in the mean color of quasars as a function of their projected separation from foreground galaxies, extending to comoving separations of ~10Mpc/h, which they interpret as a…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-06 Ying Zu , David H. Weinberg , Romeel Davé , Mark Fardal , Neal Katz , Dusan Keres , Benjamin D. Oppenheimer

We present a study of galaxies and intergalactic gas toward the z=2.73 quasar HS1700+6416, to explore the effects of galaxy formation feedback on the IGM. Our observations and ionization simulations indicate that the volume within 100-200…

Astrophysics · Physics 2009-11-13 Robert A. Simcoe , Wallace L. W. Sargent , Michael Rauch , George D. Becker

We present new high-precision measurements of the opacity of the intergalactic and circumgalactic medium (IGM, CGM) at <z>=2.4. Using Voigt profile fits to the full Lyman alpha and Lyman beta forests in 15 high-resolution high-S/N spectra…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Gwen C. Rudie , Charles C. Steidel , Alice E. Shapley , Max Pettini

We present new simulations of Lyman-$\alpha$ (Ly$\alpha$) intensity maps that include Ly$\alpha$ radiative transfer in the intergalactic medium (IGM) and all significant sources of Ly$\alpha$ photons. The sources considered include…

Astrophysics of Galaxies · Physics 2025-08-29 Abigail E. Ambrose , Eli Visbal , Mihir Kulkarni , Matthew McQuinn

The parabolic arc phenomenon visible in the Fourier analysis of the scintillation spectra of pulsars provides a new method of investigating the small scale structure in the ionized interstellar medium (ISM). We report archival observations…

Astrophysics · Physics 2011-02-11 Frank S. Trang , Barney J. Rickett

We measure the intergalactic medium (IGM) opacity in the Ly$\alpha$ as well as in the Ly$\beta$ forest along $19$ quasar sightlines between $5.5\lesssim z_{\rm abs}\lesssim 6.1$, probing the end stages of the reionization epoch. Owing to…

Astrophysics of Galaxies · Physics 2019-08-14 Anna-Christina Eilers , Joseph F. Hennawi , Frederick B. Davies , Jose Oñorbe

We investigate a method to determine the temperature-density relation of the intergalactic medium (IGM) at z~2-4 using quasar absorption line systems. Using a simple model combined with numerical simulations we show that there is a lower…

Astrophysics · Physics 2009-10-31 Greg L. Bryan , Marie E. Machacek