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Related papers: The X_CO conversion factor from galactic multiphas…

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We present the detection analysis of a diffuse molecular cloud at z$_{abs}$=2.4636 towards the quasar SDSS J1513+0352(z$_{em}\,\simeq$ 2.68) observed with the X-shooter spectrograph(VLT). We measure very high column densities of atomic and…

The HRS is a complete volume-limited sample of nearby objects including Virgo cluster and isolated objects. Using a recent compilation of HI and CO data we study the effects of the cluster on the molecular gas content of spiral galaxies. We…

Astrophysics of Galaxies · Physics 2015-06-18 A. Boselli , L. Cortese , M. Boquien , S. Boissier , B. Catinella , G. Gavazzi , C. Lagos , A. Saintonge

We use the moving mesh code AREPO coupled to a time-dependent chemical network to investigate the formation and destruction of molecular gas in simulated spiral galaxies. This allows us to determine the characteristics of the gas that is…

Astrophysics of Galaxies · Physics 2015-06-19 Rowan J. Smith , Simon C. O. Glover , Paul C. Clark , Ralf S. Klessen , Volker Springel

Carbon monoxide (CO) provides crucial information about the molecular gas properties of galaxies. While $^{12}$CO has been targeted extensively, isotopologues such as $^{13}$CO have the advantage of being less optically thick and…

While the best tracer of the molecular component and its dynamics in galaxies is the CO molecule, which excitation is revealed by its isotopic and (2-1)/(1-0) ratios, the denser gas is revealed by molecules such as HCN, HNC, HCO+ or CN,…

Astrophysics · Physics 2007-09-25 F. Combes

We examine how the post-processed content of molecular hydrogen (H$_2$) in galaxies from the TNG100 cosmological, hydrodynamic simulation changes with environment at $z\!=\!0$, assessing central/satellite status and host halo mass. We make…

Determining how galactic environment, especially the high gas densities and complex dynamics in bar-fed galaxy centers, alters the star formation efficiency (SFE) of molecular gas is critical to understanding galaxy evolution. However,…

The relationship between the star formation rate surface density and the molecular gas surface density in galaxies is key to understanding galaxy evolution. To investigate the molecular Kennicutt-Schmidt (K-S) relation and its dependence on…

Astrophysics of Galaxies · Physics 2026-04-13 Victoria G. G. Samboco , Ryan P. Keenan

We present new CO 1-0 and 2-1 observations of the N83/N84 molecular cloud complex in the south-east Wing of the Small Magellanic Cloud (SMC). While the 2-1/1-0 integrated line brightness ratio (in temperature units) is uniformly 0.9…

Astrophysics · Physics 2009-11-07 Alberto D. Bolatto , Adam Leroy , James M. Jackson , Frank P. Israel

We present a new prediction of the luminosity functions of the [CII] line at 158 $\mu$m, of the CO lines from J=0 to J=24, and of the molecular gas mass density up to z=10, using the Spectro-Photometric Realisations of Infrared-selected…

Astrophysics of Galaxies · Physics 2022-10-26 L. Bisigello , L. Vallini , C. Gruppioni , F. Esposito , F. Calura , I. Delvecchio , A. Feltre , F. Pozzi , G. Rodighiero

We present ALMA observations of a small but statistically complete sample of twelve 250 micron selected galaxies at $z=0.35$ designed to measure their dust submillimeter continuum emission as well as their CO(1-0) and atomic carbon…

Astrophysics of Galaxies · Physics 2021-11-18 L. Dunne , S. J. Maddox , C. Vlahakis , H. L. Gomez

The distribution and physical conditions of molecular gas are closely linked to star formation and the subsequent evolution of galaxies. Emission from carbon monoxide (CO) and its isotopologues traces the bulk of molecular gas and provides…

The lines of HOC$^+$, HCO and CO$^+$ are considered good tracers of photon-dominated regions (PDRs) and X-ray dominated regions. We study these tracers towards regions of the Sgr B2 cloud selected to be affected by different heating…

We have conducted OH 18 cm survey toward 141 molecular clouds in various environments, including 33 optical dark clouds, 98 Planck Galactic cold clumps (PGCCs) and 10 Spitzer dark clouds with the Arecibo telescope. The deviations from local…

Astrophysics of Galaxies · Physics 2020-12-23 Ningyu Tang , Di Li , Nannan Yue , Pei Zuo , Tie Liu , Gan Luo , Longfei Chen , Sheng-Li Qin , Yuefang Wu , Carl Heiles

Using the IRAM 30-m telescope, we have obtained 12CO J=1-0 and 2-1 spectral line observations toward the nuclear regions of 15 edge-on, low surface brightness (LSB) spiral galaxies. Our sample comprises extreme late-type LSB spirals with…

Astrophysics · Physics 2009-11-10 Lynn D. Matthews , Yu Gao , Juan M. Uson , Francoise Combes

We present new empirical constraints on the evolution of $\rho_{\rm H_2}$, the cosmological mass density of molecular hydrogen, back to $z\approx2.5$. We employ a statistical approach measuring the average observed $850\mu{\rm m}$ flux…

We make use of our 'minimal' cold interstellar medium (ISM) emission line model that predicts the molecular and atomic line emission per unit dense, star-forming gas mass (Geach & Papadopoulos 2012; Paper I) to examine the utility of key…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Padelis P. Papadopoulos , James E. Geach

We model the effect of grain size distribution in a galaxy on the evolution of CO and H$_2$ abundances. The formation and dissociation of CO and H$_2$ in typical dense clouds are modelled in a manner consistent with the grain size…

Astrophysics of Galaxies · Physics 2023-05-10 Hiroyuki Hirashita

Context: It has been proposed that H$_2$ near-infrared lines may be excited by cosmic rays and allow for a determination of the cosmic-ray ionization rate in dense gas. One-dimensional models show that measuring both the H$_2$ gas column…

Astrophysics of Galaxies · Physics 2022-08-24 Brandt A. L. Gaches , Shmuel Bialy , Thomas G. Bisbas , Marco Padovani , Daniel Seifried , Stefanie Walch

Light-matter interactions lie at the heart of our exploration of exoplanetary atmospheres. Interpreting data obtained by remote sensing is enabled by meticulous, time- and resource-consuming work aiming at deepening our understanding of…

Earth and Planetary Astrophysics · Physics 2025-03-06 Laurent Wiesenfeld , Prajwal Niraula , Julien de Wit , Nejmeddine Jaïdane , Iouli E. Gordon , Robert J. Hargreaves