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Related papers: Small-Scale structure in the Galactic ISM: Implica…

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Nearby interstellar clouds with high (|v| >/= 10 km/s) random velocities although easily detected in NaI and CaII lines have hitherto not been detected (in emission or absorption) in the HI 21cm line. We describe here deep Giant Metrewave…

Astrophysics · Physics 2009-11-06 Rekhesh Mohan , K. S. Dwarakanath , G. Srinivasan , Jayaram N. Chengalur

In order to investigate the contribution of diffuse components to their total HI emission, we have obtained high precision HI line flux densities with the 100m Green Bank Telescope for a sample of 100 isolated spiral and irregular galaxies…

Astrophysics · Physics 2008-11-26 David E. Hogg , Morton S. Roberts , Martha P. Haynes , Ronald J. Maddalena

We present Giant Metrewave Radio Telescope (GMRT) observations of redshifted 21-cm absorption from the $z=0.437$ metal line absorption system towards PKS 1243-072. HI absorption is clearly detected; the absorption profile has a velocity…

Astrophysics · Physics 2009-11-07 Nissim Kanekar , Ramana M. Athreya , Jayaram N. Chengalur

We exploit observations at 1.25 mm with the ESO-SEST telescope of a southern galaxy sample, selected from the IRAS PSC and complete to $S_{60}=2 Jy$, to derive the FIR and mm luminosity functions and the conditional probability…

Astrophysics · Physics 2009-10-30 A. Franceschini , P. Andreani , L. Danese

Different physical processes in galaxy evolution, such as galaxy mergers that lead to coalescence of dual Active Galactic Nuclei (AGN) and outflows emanating from the narrow line region, can leave their imprint on the optical spectra of AGN…

Astrophysics of Galaxies · Physics 2022-09-08 Rajeshwari Dutta , Raghunathan Srianand

The absorption feature in the global spectrum is likely the first 21 cm observable from the cosmic dawn, which provides valuable insights into the earliest history of structure formation. We run a set of high-resolution hydrodynamic…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-23 Yidong Xu , Bin Yue , Xuelei Chen

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

In this paper we consider a large sample of optically selected clusters, in order to elucidate the physical reasons for the existence of X-ray underluminous clusters. For this purpose we analyze the correlations of the X-ray and optical…

Astrophysics · Physics 2009-11-11 P. Popesso , A. Biviano , H. Böhringer , M. Romaniello

Using a set of ROSAT HRI deep pointings, we investigate the presence of small-scale structures in the central regions of clusters of galaxies. Our sample comprises 23 objects up to z=0.32, 13 of them known to host a cooling flow. Structures…

Astrophysics · Physics 2007-05-23 Marguerite Pierre , Jean-Luc Starck

Environment plays an important role in the evolution of the gas contents of galaxies. Gas deficiency of cluster spirals and the role of the hot intracluster medium (ICM) in stripping gas from these galaxies is a well studied subject. Loose…

Astrophysics · Physics 2008-11-26 Chandreyee Sengupta , Ramesh Balasubramanyam , K. S. Dwarakanath

We present spatially-resolved spectroscopy of the galaxy cluster Abell S1101, also known as Sersic 159-03, with Chandra, XMM-Newton and ROSAT, and investigate the presence of soft X-ray excess emission above the contribution from the hot…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Max Bonamente , Jukka Nevalainen

Twenty-two powerful radio galaxies have been searched for HI absorption. We find the highest probability of detecting HI in absorption among narrow-line compact (or small) galaxies or galaxies with indication of richer interstellar medium…

Astrophysics · Physics 2007-05-23 R. Morganti , T. A. Oosterloo , G. van Moorsel , C. N. Tadhunter , N. Killeen

We present measurements of the oxygen abundance of the Milky Way's ISM by observing the K-shell X-ray photoionization edge towards galaxy clusters. This effect is most easily observed towards objects with galactic columns (n_H) of a few…

Astrophysics · Physics 2009-11-13 Wayne H. Baumgartner , Richard F. Mushotzky

We present results from a search for the HI 21-cm line in absorption towards 16 bright radio sources with the 6-antenna commissioning array of the Australian Square Kilometre Array Pathfinder (ASKAP). Our targets were selected from the 2-Jy…

The low column density gas at the outskirts of galaxies as traced by the 21 cm hydrogen line emission (HI) represents the interface between galaxies and the intergalactic medium, i.e., where galaxies are believed to get their supply of gas…

Astrophysics of Galaxies · Physics 2018-05-23 Roger Ianjamasimanana , Fabian Walter , W. J. G. de Blok , George H. Heald , Elias Brinks

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

The intensity of the soft X-Ray background is correlated with the distribution of galaxies. To demonstrate this, magnitude limited galaxy samples extracted from bright galaxy catalogues and the Lick counts are utilized. Significant…

The Galactic Cold Cores (GCC) project has made Herschel observations of interstellar clouds where Planck detected compact sources of cold dust emission. Our aim is to characterise the structure of the clumps and their parent clouds. We also…

Astrophysics of Galaxies · Physics 2018-06-20 M. Juvela , J. Malinen , J. Montillaud , V. -M. Pelkonen , I. Ristorcelli , L. V. Toth

The surface brightness produced by synchrotron radiation in Clusters of Galaxies with a radio-halo sets a degenerate constraint on the magnetic field strength, the relativistic electron density and their spatial distributions. Using the…

Astrophysics · Physics 2009-11-13 S. Colafrancesco , P. Marchegiani , G. C. Perola

The large scale distribution of galaxies in the universe displays a complex pattern of clusters, super-clusters, filaments and voids with sizes limited only by the boundaries of the available samples. A quantitative statistical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Francesco Sylos Labini , Luciano Pietronero