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Related papers: Scattered H-alpha light from Galactic dust clouds

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We have carried out a survey searching for H alpha emitting galaxies at z~0.24 using a narrow band filter tuned with the redshifted line. The total sky area covered was 0.19 square degrees within the redshift range 0.228 to 0.255 in a set…

Astrophysics · Physics 2009-11-07 S. Pascual , J. Gallego , A. Aragon-Salamanca , J. Zamorano

We have discovered ultraviolet halos extending as far as 5{\deg} around four (of six) bright UV stars using data from the GALEX satellite. These halos are due to the scattering of the starlight from nearby thin, foreground dust clouds. We…

Astrophysics of Galaxies · Physics 2011-09-13 Jayant Murthy , Richard Conn Henry

"Diffuse" gamma rays consist of several components: truly diffuse emission from the interstellar medium, the extragalactic background, whose origin is not firmly established yet, and the contribution from unresolved and faint Galactic point…

Astrophysics · Physics 2015-06-24 I. V. Moskalenko , A. W. Strong , O. Reimer

In previous studies, it has been shown that the large line widths observed in high surface brightness H-alpha emitters at low and high redshifts are likely due to the mechanical energy injected by intense star formation. Here we discuss the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Loïc Le Tiran , Matthew D. Lehnert , Paola Di Matteo , Nicole P. H. Nesvadba , Wim van Driel

We review the Lyan alpha emission in local star-forming galaxies. In most cases as already shown by the IUE, the emission is absent or much weaker than expected. This occurs because Lyman alpha photons can be resonantly scattered by the…

Astrophysics · Physics 2007-05-23 D. Kunth , E. Terlevich , R. Terlevich , G. Tenorio-Tagle

In the powerful, high redshift radio galaxies, it is believed that the dominant source of ionization for the interstellar gas is the hard radiation field associated with the active nucleus. The photon source is generally external to the…

Astrophysics · Physics 2007-05-23 M. Villar-Martin , L. Binette , R. A. E. Fosbury

Models are presented for the Lyman alpha emission of dusty high-redshift galaxies by combining the Press-Schechter formalism with a treatment of the inhomogeneous dust distribution inside galaxies. It is found that the amount of Lyman alpha…

Astrophysics · Physics 2008-11-26 Zoltan Haiman , Marco Spaans

Modelling of Extreme Scattering Events suggests that the Galaxy's dark matter is an undetected population of cold, AU-sized, planetary-mass gas clouds. None of the direct observational constraints on this picture -- thermal/non-thermal…

Astrophysics · Physics 2015-06-24 Mark Walker , Mark Wardle

The velocity structure imprinted in the H{\alpha} emission line profiles contains valuable information about galactic outflows. Using a set of high-resolution zoom-in cosmological simulations of galaxies at z=2, we generate H{\alpha}…

Astrophysics of Galaxies · Physics 2016-07-27 Daniel Ceverino , Santiago Arribas , Luis Colina , Bruno Rodriguez Del Pino , Avishai Dekel , Joel Primack

We have detected faint, diffuse H$\alpha emission from several points along the Magellanic Stream, using the Rutgers Fabry--Perot Interferometer at the CTIO 1.5-m telescope. At points on the leading edges of the H I clouds MS II, MS III,…

Astrophysics · Physics 2008-11-26 Benjamin J. Weiner , T. B. Williams

We compare vertical profiles of the extraplanar H$\alpha$ emission to those of the UV emission for 38 nearby edge-on late-type galaxies. It is found that detection of the "diffuse" extraplanar dust (eDust), traced by the vertically…

Astrophysics of Galaxies · Physics 2018-08-01 Young-Soo Jo , Kwang-il Seon , Jong-Ho Shinn , Yujin Yang , Dukhang Lee , Kyoung-Wook Min

The high-redshift Universe contains luminous Lyman Alpha (hereafter Lya) emitting sources such as galaxies and quasars. The emitted Lya radiation is often scattered by surrounding neutral hydrogen atoms. We show that the scattered Lya…

Astrophysics · Physics 2009-11-13 Mark Dijkstra , Abraham Loeb

The results of a spectroscopic survey of H alpha emission line stars associated with fourteen bright rimmed clouds are presented. Slit-less optical spectroscopy was carried out with the Inter University Centre for Astronomy and Astrophysics…

Solar and Stellar Astrophysics · Physics 2020-06-02 Kensuke Hosoya , Yoichi Itoh , Yumiko Oasa , Ranjan Gupta , Asoke Kumar Sen

Small angle scatterings of X-rays by interstellar dust particles create halos around x-ray sources. By observing these halos with sufficient angular resolution it is possible to derive information about both the spatial distribution of the…

Astrophysics · Physics 2009-10-30 Randall K. Smith , Eli Dwek

This document provides a brief summary estimate of Galactic free-free emission and H-alpha emission and their relationship. Particular emphasis is placed on estimating the potential free-free emission in the region of significant confusion…

Astrophysics · Physics 2007-05-23 George F. Smoot

High resolution X-ray imaging offers a unique opportunity to probe the nature of dust in the z ~< 2 universe. Dust grains 0.1- 1 um in size will scatter soft X-rays, producing a diffuse "halo" image around an X-ray point source, with a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Lia Corrales , Frits Paerels

We measure the optical spectrum of the Diffuse Galactic Light (DGL) -- the local Milky Way in reflection -- using 92,000 blank-sky spectra from the Sloan Digital Sky Survey (SDSS). We correlate the SDSS optical intensity in regions of blank…

Astrophysics of Galaxies · Physics 2011-12-23 Timothy D. Brandt , Bruce T. Draine

Near-infrared (IR) diffuse Galactic light (DGL) consists of scattered light and thermal emission from interstellar dust grains illuminated by interstellar radiation field (ISRF). At 1.25 and 2.2um, recent observational study shows that…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-08 Kei Sano , Shuji Matsuura

Cluster star-forming galaxies are found to have an excess of Far-Infrared emission relative to H-alpha (Ha), when compared to those in the field, which could be caused by intense AGN activity, dust and/or declining star formation histories.…

Astrophysics of Galaxies · Physics 2016-03-23 David Sobral , Andra Stroe , Yusei Koyama , Behnam Darvish , João Calhau , Ana Afonso , Tadayuki Kodama , Fumiaki Nakata

Diffuse emission from the Milky Way dominates the gamma-ray sky. About 80% of the high-energy luminosity of the Milky Way comes from processes in the interstellar medium. The Galactic diffuse emission traces interactions of energetic…

Astrophysics · Physics 2009-02-25 T. A. Porter , S. W. Digel , I. A. Grenier , I. V. Moskalenko , A. W. Strong