English
Related papers

Related papers: Selection Effects at 21cm

200 papers

Over the past decade, Lyman-alpha and metal line absorption observations have established the ubiquity of a gas-rich circumgalactic medium (CGM) around star-forming galaxies at z~0.2 potentially tracing half of the missing baryonic mass…

Astrophysics of Galaxies · Physics 2019-03-19 D. J. Pisano , A. Fox , D. French , J. C. Howk , N. Lehner , F. J. Lockman , K. Jones

The Lyman-$\alpha$ (Lya) line of hydrogen is a well-known tracer of galaxies at high-z. However, the connection between Lya observables and galaxy properties has not fully been established, limiting the use of the line to probe the physics…

21cm radiation from neutral hydrogen serves as a direct probe of the Epoch of Reionization. However, both its detection and physical interpretation are severely hindered by contamination from astrophysical foreground emission and…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Anirban Chakraborty , Kwanit Gangopadhyay , Arka Banerjee , Tirthankar Roy Choudhury

We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15-0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope.…

Unlike the neutral gas density, which remains largely constant over redshifts of 0 < z < 5, the star formation density exhibits a strong redshift dependence, increasing from the present day before peaking at a redshift of z ~ 2.5. Thus,…

Astrophysics of Galaxies · Physics 2017-10-11 S. J. Curran

We report on the neutral hydrogen gas content (21-cm emission) of eight extremely isolated early-type galaxies (IEGs) using the Green Bank Telescope. Emission is detected in seven of the eight objects. This paper is the third in a series…

Astrophysics of Galaxies · Physics 2019-04-10 Trisha Ashley , Pamela M. Marcum , Mehmet Alpaslan , Michael N. Fanelli , James D. Frost

Intensity mapping -- the large-scale mapping of selected spectral lines without resolving individual sources -- is quickly emerging as an efficient way to conduct large cosmological surveys. Multiple surveys covering a variety of lines…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Hannah Fronenberg , Adrian Liu

Atomic Hydrogen (HI) is a useful tracer of gas in and around galaxies, and can be found in extended disk-like structures well beyond a system's optical extent. Here we investigate the properties of extended HI disks that emerge in six Milky…

A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At…

Astrophysics of Galaxies · Physics 2015-06-15 Yurii Pidopryhora , Felix J. Lockman , John M. Dickey , Michael P. Rupen

The presence of dense, neutral hydrogen clouds in the hot, diffuse intra-group and intra-cluster medium is an important clue to the physical processes controlling the survival of cold gas and sheds light on cosmological baryon flows in…

Astrophysics of Galaxies · Physics 2024-04-29 Avinash Chaturvedi , Stephanie Tonnesen , Greg L. Bryan , Gergö Popping , Michael Hilker , Paolo Serra , Shy Genel

We present a catalog of holes and shells in the neutral atomic hydrogen (\HI) of 41 gas-rich dwarf galaxies in LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The \HI Nearby Galaxy Survey). We analyzed their properties as…

Astrophysics of Galaxies · Physics 2020-07-22 Nau Raj Pokhrel , Caroline E. Simpson , Ioannis Bagetakos

We carried out synthetic observations of interstellar atomic hydrogen at 21cm wavelength by utilizing the magneto-hydrodynamical numerical simulations of the inhomogeneous turbulent interstellar medium (ISM) Inoue and Inutsuka (2012). The…

Areas of massive star formation are strongly influenced by stellar winds and supernovae, therefore, enhanced turbulent flows are expected. We analyse high-quality Karl G. Jansky Very Large Array observations of the neutral hydrogen gas…

Astrophysics of Galaxies · Physics 2025-03-25 Enikő Pichler , Bendegúz Koncz , Krisztina É. Gabányi , András Péter Joó , L. Viktor Tóth

We aim at analysing systematically the distribution and physical properties of neutral and mildly ionised gas in the Milky Way halo, based on a large absorption-selected data set. Multi-wavelength studies were performed combining optical…

Astrophysics of Galaxies · Physics 2015-06-04 N. Ben Bekhti , B. Winkel , P. Richter , J. Kerp , U. Klein , M. T. Murphy

We compare the dust attenuation properties of two samples of galaxies purely selected in the near-ultraviolet (NUV) band (1750-2750 A, lambda_m = 2310 A) and in the far-infrared (FIR) at 60micron. These samples are built using the GALEX and…

The global 21 cm HI emission-line profile of a galaxy encodes valuable information on the spatial distribution and kinematics of the neutral atomic gas. Galaxy interactions significantly influence the HI disk and imprint observable features…

Astrophysics of Galaxies · Physics 2022-04-20 Pei Zuo , Luis C. Ho , Jing Wang , Niankun Yu , Jinyi Shangguan

The atomic hydrogen (HI) 21cm line measures the gas content within and around galaxies, traces the dark matter potential and probes volumes and objects that other surveys do not. Over the next decade, 21cm line science will exploit new…

Astrophysics · Physics 2009-11-13 Martha P. Haynes

We present 21-cm HI line and optical R-band observations for a sample of 26 edge-on galaxies. The HI observations were obtained with the Westerbork Synthesis Radio Telescope, and are part of the WHISP database (Westerbork HI Survey of…

Astrophysics · Physics 2016-08-30 I. Garcia-Ruiz , R. Sancisi , K. Kuijken

We discuss the feasibility of the detection of the 21cm forest in the diffuse IGM with the radio telescope LOFAR. The optical depth to the 21cm line has been derived using simulations of reionization which include detailed radiative…

Active galaxies are thought to be both fueled and obscured by neutral gas removed from the host galaxy and funneled into a central accretion disk. We performed a VLA imaging survey of 21 cm absorption in Seyfert and starburst nuclei to…

Astrophysics · Physics 2009-10-31 J. F. Gallimore , S. A. Baum , C. P. O'Dea , A. Pedlar , E. Brinks
‹ Prev 1 4 5 6 7 8 10 Next ›