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Related papers: A molecular gas phase in the Cold Neutral Medium?

200 papers

The extent to which the ISM in galaxies is well mixed is not yet settled. Measured metal abundances in the diffuse neutral gas of star--forming gas--rich dwarf galaxies are deficient with respect to that of the ionized gas. The reasons, if…

Astrophysics · Physics 2015-11-11 Vianney Lebouteiller , Daniel Kunth

The interstellar medium (ISM) has a multiphase structure characterized by gas, dust and molecules. The gas can be found in different charge states: neutral, low-ionized (warm) and high-ionized (hot). It is possible to probe the multiphase…

High Energy Astrophysical Phenomena · Physics 2013-02-19 C. Pinto , J. S. Kaastra , E. Costantini , F. Verbunt

The detailed distribution and kinematics of the atomic and the CO-bright molecular hydrogen in the disc of the Milky Way inside the Solar circle are derived under the assumptions of axisymmetry and pure circular motions. We divide the…

Astrophysics of Galaxies · Physics 2017-11-22 A. Marasco , F. Fraternali , J. M. van der Hulst , T. Oosterloo

We show that gaseous \HI disks of primordial composition irradiated by an external radiation field can develop a multiphase medium with temperatures between 10^2 and 10^4 K due to the formation of molecular hydrogen. For a given \HI column…

Astrophysics · Physics 2009-10-30 Edvige Corbelli , Daniele Galli , Francesco Palla

Dynamic and thermal processes regulate the structure of the multi-phase interstellar medium (ISM), and ultimately establish how galaxies evolve through star formation. Thus, to constrain ISM models and better understand the interplay of…

We know little about the outermost portions of galaxies because there is little light coming from them. We do know that in many cases atomic hydrogen (HI) extends well beyond the optical radius \cite{Casertano91}. In the centers of…

Astrophysics · Physics 2009-11-10 Jonathan Braine , Fabrice Herpin

We use a sample of 47 homogeneous and high sensitivity CO images taken from the Nobeyama and BIMA surveys to demonstrate that, contrary to common belief, a significant number (~40%) of HI-deficient nearby spiral galaxies are also depleted…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Michele Fumagalli , Mark R. Krumholz , J. Xavier Prochaska , Giuseppe Gavazzi , Alessandro Boselli

We present an analysis of the neutral hydrogen (HI) properties of a fully cosmological hydrodynamical dwarf galaxy, run with varying simulation parameters. As reported by Governato et al. (2010), the high resolution, high star formation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 K. Pilkington , B. K. Gibson , F. Calura , A. M. Brooks , L. Mayer , C. B. Brook , G. S. Stinson , R. J. Thacker , C. G. Few , D. Cunnama , J. Wadsley

[Abridged] Do some environments favor efficient conversion of molecular gas into stars? To answer this, we need to be able to estimate the H2 mass. Traditionally, this is done using CO and a few assumptions but the Herschel observations in…

We examine the triggering process of molecular cloud formation around diffuse HII regions. We calculate the time evolution of the shell as well as of the HII region in a two-phase neutral medium, solving the UV and FUV radiative transfer,…

Astrophysics · Physics 2011-02-11 Takashi Hosokawa , Shu-ichiro Inutsuka

We present high-resolution, optical images (BVI + Halpha) of the multiphase interstellar medium (ISM) in the thick disks of the edge-on spiral galaxies NGC 4013 and NGC 4302. Our images from the Hubble Space Telescope, Large Binocular…

Recent, high sensitivity, HI observations of nearby spiral galaxies show that their thin `cold' disks are surrounded by thick layers (halos) of neutral gas with anomalous kinematics. We present results for three galaxies viewed at different…

Astrophysics · Physics 2007-05-23 Filippo Fraternali , Tom Oosterloo , Rense Boomsma , Rob Swaters , Renzo Sancisi

Ionized carbon is the main gas-phase reservoir of carbon in the neutral diffuse interstellar medium and its 158 micron fine structure transition [CII] is the most important cooling line of the diffuse interstellar medium (ISM). We combine…

Gas and dust in star-forming galaxies at the peak epoch of galaxy assembly are presently the topic of intense study, but little is known about the interstellar medium (ISM) of distant, passively evolving galaxies. We report on a deep 3…

Astrophysics of Galaxies · Physics 2015-06-17 Mark T. Sargent , E. Daddi , F. Bournaud , M. Onodera , C. Feruglio , M. Martig , R. Gobat , H. Dannerbauer , E. Schinnerer

The interstellar medium is a multiphase gas in which turbulent support is as important as thermal pressure. Sustaining this configuration requires both continuous turbulent stirring and continuous radiative cooling to match the decay of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Evan Scannapieco

We investigate the relationship between HI, H_2, and the star formation rate (SFR) using azimuthally averaged data for seven CO-bright spiral galaxies. Contrary to some earlier studies based on global fluxes, we find that the SFR surface…

Astrophysics · Physics 2009-11-07 Tony Wong , Leo Blitz

We present new mm interferometric and optical integral-field unit (IFU) observations and construct a sample of 12 E and S0 galaxies with molecular gas which have both CO and optical maps. The galaxies contain 2 x 10^7 to 5 x 10^9 M\odot of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Alison F. Crocker , Martin Bureau , Lisa M. Young , Francoise Combes

We have mapped cold atomic gas in 21cm line HI self-absorption (HISA) at arcminute resolution over more than 90% of the Milky Way's disk. To probe the formation of H2 clouds, we have compared our HISA distribution with CO J=1-0 line…

We review here the main direct or indirect ways to detect the possible presence of large amounts of cold molecular hydrogen in the outer parts of disk galaxies, an hypothesis that we have recently developed. Direct ways range from H2…

Astrophysics · Physics 2007-05-23 F. Combes , D. Pfenniger

Abridged. Low-metallicity star-forming dwarf galaxies are prime targets to understand the chemical enrichment of the interstellar medium. The HI region provides important constraints on the dispersal and mixing of heavy elements released by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Vianney Lebouteiller , Sara Heap , Ivan Hubeny , Daniel Kunth