English
Related papers

Related papers: The H$\alpha$ sky in three dimensions

200 papers

We present Wisconsin H-Alpha Mapper [S II] {\lambda}6716 and H{\alpha} spectroscopic maps of the warm ionized medium (WIM) in the Scutum-Centaurus Arm at Galactic longitudes 310{\deg} < l < 345{\deg}. Using extinction-corrected H{\alpha}…

Astrophysics of Galaxies · Physics 2014-05-12 Alex S. Hill , Robert A. Benjamin , L. Matthew Haffner , Martin Gostisha , Kathleen A. Barger

Cross-correlation of the DIRBE 100 micron survey with previously published H-alpha maps tests correlations between far-infrared dust and the warm ionized interstellar medium in different regions of the sky. A 10 x 12 deg patch at Galactic…

Astrophysics · Physics 2009-10-30 A. Kogut

Close-in hot Jupiters are exposed to a tremendous photon flux that ionizes the neutral escaping material from the planet leaving an observable imprint that makes them an interesting laboratory for testing theoretical models. In this work we…

Earth and Planetary Astrophysics · Physics 2016-02-17 E. M. Schneiter , A. Esquivel , C. S. Villarreal D'Angelo , P. F. Velazquez , A. C. Raga , A. Costa

We present a three-dimensional model of polarised galactic dust emission that takes into account the variation of the dust density, spectral index and temperature along the line of sight, and contains randomly generated small scale…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Ginés Martínez-Solaeche , Ata Karakci , Jacques Delabrouille

The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the…

Astrophysics of Galaxies · Physics 2013-08-06 Kathleen A. Barger , Lawrence M. Haffner , Bart P. Wakker , Alex S. Hill , Greg J. Madsen , Allison K. Duncan

We analyze H$\alpha$ images and long-slit spectra of samples of normal and starburst galaxies to better understand the nature of the diffuse, low-surface-brightness gas in these galaxies. We find that in both samples there is a strong…

Astrophysics · Physics 2016-08-30 Jing Wang , Timothy M. Heckman , Matthew D. Lehnert

The Diffuse Ionised Gas (DIG) in galaxies traces photoionisation feedback from massive stars. Through three dimensional photoionisation simulations, we study the propagation of ionising photons, photoionisation heating and the resulting…

Astrophysics of Galaxies · Physics 2015-06-19 J. E. Barnes , Kenneth Wood , Alex S. Hill , L. M. Haffner

Optical emission lines have now been detected from about 20 high velocity clouds. These emission lines -- primarily H-alpha, secondarily [N II] and [S II] -- are very faint and diffuse, spread over the surfaces of the clouds. We compile…

Astrophysics · Physics 2007-05-23 Benjamin J. Weiner , Stuart N. Vogel , T. B. Williams

Kowalski & Saumon (2006) identified the missing absorption mechanism in the observed spectra of cool white dwarf stars as the Ly-alpha red wing formed by the collisions between atomic and molecular hydrogen and successfully explained entire…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. D. Rohrmann , L. G. Althaus , S. O. Kepler

Large stellar surveys are sensitive to interstellar dust through the effects of reddening. Using extinctions measured from photometry and spectroscopy, together with three-dimensional (3D) positions of individual stars, it is possible to…

Astrophysics of Galaxies · Physics 2018-10-31 Sara Rezaei Kh. , Coryn A. L. Bailer-Jones , David W. Hogg , Mathias Schultheis

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

The atomic hydrogen gas (HI) disk in the outer region (beyond ~10 kpc from the centre) of Milky Way can provide valuable information about the structure of the dark matter halo. The recent 3-D thickness map of the outer HI disk from the all…

Astrophysics of Galaxies · Physics 2011-02-11 Kanak Saha , Evan S. Levine , Chanda J. Jog , Leo Blitz

We use very large cosmological Smoothed-Particle-Hydrodynamics simulations to study the properties of high redshift Lyman-alpha emitters (LAEs). We identify star-forming galaxies at z=3.1 in a cosmological volume of 100 h^-1Mpc on a side.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Ikkoh Shimizu , Naoki Yoshida , Takashi Okamoto

The fraction of ionizing photons that escape high-redshift galaxies sensitively determines whether galaxies reionized the early universe. However, this escape fraction cannot be measured from high-redshift galaxies because the opacity of…

Astrophysics of Galaxies · Physics 2018-08-08 J. Chisholm , S. Gazagnes , D. Schaerer , A. Verhamme , J. R. Rigby , M. Bayliss , K. Sharon , M. Gladders , H. Dahle

Spectroscopic observations of Halpha and Hbeta emission lines of 128 star-forming galaxies in the redshift range 0.75<z<1.5 are presented. These data were taken with slitless spectroscopy using the G102 and G141 grisms of the…

Hydrodynamic simulations of Lyman alpha clouds based on ab inito cosmological models have produced results that are in broad agreement with observations. However, further analyses have revealed that, with progressively higher numerical…

Astrophysics · Physics 2009-10-31 Renyue Cen , Greg L. Bryan

We present newly obtained three-dimensional gaseous maps of the Milky Way Galaxy; HI, H$_2$ and total-gas (HI plus H$_2$) maps, which were derived from the HI and $^{12}$CO($J=1$--0) survey data and rotation curves based on the kinematic…

Astrophysics of Galaxies · Physics 2015-12-01 Hiroyuki Nakanishi , Yoshiaki Sofue

We modelled recent observations of UV absorption of HD and \HH\ in the Milky Way and toward damped/sub-damped Lyman alpha systems at z=0.18 and z $>$ 1.7. N(HD)/N(\HH) ratios reflect the separate self-shieldings of HD and \HH\ and the…

Astrophysics of Galaxies · Physics 2015-06-23 H. S. Liszt

We present model calculations of ionization fractions for elements in the warm (log T = 4), low-density photoionized interstellar medium (WIM) of the Milky Way. We model the WIM as a combination of overlapping low-excitation H II regions…