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Related papers: Helium line detections from ELDWIM at 1.4 GHz

200 papers

We use observations made with the Giant Metrewave Radio Telescope (GMRT) to probe the neutral hydrogen (HI) gas content of field galaxies in the VIMOS VLT Deep Survey (VVDS) 14h field at $z \approx 0.32$. Because the HI emission from…

Diffuse radio recombination lines (RRLs) in the Galaxy are possible foregrounds for redshifted 21~cm experiments. We use EDGES drift scans centered at $-26.7^o$~declination to characterize diffuse RRLs across the southern sky. We find RRLs…

WSRT observations have been used to investigate the presence of neutral hydrogen in extremely young radio galaxies. These objects were selected from a sample of High-Frequency Peakers (HFPs). We detect 2 of the 6 observed galaxies…

Astrophysics · Physics 2009-11-11 M. Orienti , R. Morganti , D. Dallacasa

The hardness of the ionizing continuum from the first sources of UV radiation plays a crucial role in the reionization of the intergalactic medium (IGM). While usual stellar populations have soft spectra, mini-quasars or metal-free stars…

Astrophysics · Physics 2009-10-31 S. Peng Oh , Zoltan Haiman , Martin J. Rees

Neutral hydrogen (HI) is the primary component of the cool interstellar medium (ISM) and is the reservoir of fuel for star formation. Owing to the sensitivity of existing radio telescopes, our understanding of the evolution of the ISM in…

We present the first results of a targeted survey carried out with the 305 m Arecibo telescope to detect HI-line emission from galaxies at redshift z>0.16. The targets, selected from the Sloan Digital Sky Survey database, are…

Optical emission lines are used to categorize galaxies into three groups according to their dominant central radiation source: active galactic nuclei, star formation, or low-ionization (nuclear) emission regions [LI(N)ERs] that may trace…

Astrophysics of Galaxies · Physics 2020-07-07 Dhanesh Krishnarao , Robert A. Benjamin , L. Matthew Haffner

We spectroscopically identify 101 Galactic HII regions using spectra from the Large Sky Area Multi- Object Fiber Spectroscopic Telescope (LAMOST) survey, cross-matched with an HII region catalog derived from the all-sky Wide-Field Infrared…

Astrophysics of Galaxies · Physics 2018-10-24 Li-Li Wang , A-Li Luo , Wen Hou , Meng-Xin Wang , Bing Du , Li Qin , Jin-Shu Han

We present an analysis of the galaxy environment and physical properties of a partial Lyman limit system at z = 0.83718 with HI and metal line components closely separated in redshift space ($|\Delta v| \approx 400$ km/s) towards the…

We report on observations of several optical emission lines toward a variety of newly revealed faint, large-scale H-alpha-emitting structures in the warm ionized medium (WIM) of the Galaxy. The lines include [N II] 6583, [N II] 5755, [S II]…

Astrophysics · Physics 2007-05-23 G. J. Madsen

Synchrotron emission pervades the Galactic plane at low radio frequencies, originating from cosmic ray electrons interacting with the Galactic magnetic field. Using a low-frequency radio telescope, the Murchison Widefield Array (MWA), we…

We have conducted Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of LiH, in absorption, toward three quasars. These quasars, B0218+357, PKS1830-211, and PKS0201+113, have redshifts of z = 0.685 - 3.387$, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 D. N. Friedel , Athol Kemball , Brian D. Fields

We perform an HI stacking analysis to study the relation between HI content and optical/radio/IR properties of galaxies located in the Lockman Hole area. In the redshift range covered by the observations (up to z = 0.09), we use the SDSS to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 K. Geréb , R. Morganti , T. A. Oosterloo , G. Guglielmino , I. Prandoni

We present the first results of the JWST Emission Line Survey (JELS). Utilising the first NIRCam narrow-band imaging at 4.7$\mu$m, over 63 arcmin$^{2}$ in the PRIMER/COSMOS field, we identified 609 emission line galaxy candidates. From…

The near-infrared helium triplet line is a powerful tool for studying atmospheric escape processes of close-in exoplanets, especially irradiated gas giants. Line profile fitting provides direct insight into the mechanisms driving…

Neutral hydrogen traces gravitational potentials. In the nearby universe, 21cm emission-line surveys show that the bulk of the HI resides in well-formed, optically-luminous galaxies. At high redshift, 21cm line absorption against background…

Astrophysics · Physics 2007-05-23 F. H. Briggs

Detecting neutral hydrogen structures in the intergalactic medium (IGM) during cosmic reionization via absorption (21 cm forest) against a background radiation is considered independent and complementary to the three-dimensional tomography…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-10 Nithyanandan Thyagarajan

The cosmological missing baryons at z<1 most likely hide in the hot (T$\gtrsim10^{5.5}$ K) phase of the Warm Hot Intergalactic Medium (WHIM). While the hot WHIM is hard to detect due to its high ionisation level, the warm…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-16 J. Nevalainen , E. Tempel , J. Ahoranta , L. J. Liivamagi , M. Bonamente , E. Tilton , J. Kaastra , T. Fang , P. Heinamaki , E. Saar , A. Finoguenov

We derive direct measurement gas-phase metallicities of $7.4 < 12 + \log(O/H) < 8.4$ for 14 low-mass Emission Line Galaxies (ELGs) at $0.3 < z < 0.8$ identified in the Faint Infrared Grism Survey (FIGS). We use deep slitless G102 grism…

We present a pilot study of extragalactic HI 21-cm absorption lines using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We observed 5 continuum sources with HI absorption features firstly identified in the 40% data…

Astrophysics of Galaxies · Physics 2021-03-31 Bo Zhang , Ming Zhu , Zhong-Zu Wu , Qing-Zheng Yu , Peng Jiang , You-Ling Yue , Meng-Lin Huang , Qiao-Li Hao