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Related papers: Cold HI in faint dwarf galaxies

200 papers

We apply novel survival analysis techniques to investigate the relationship between a number of the properties of galaxies and their atomic ($M_\mathrm{HI}$) and molecular ($M_{\mathrm{H_2}}$) gas mass, with the aim of devising efficient,…

Astrophysics of Galaxies · Physics 2019-11-06 Hassen M. Yesuf , Luis C. Ho

We use HI absorption measurements to constrain the amount of cool ($\approx 10^4$ K), photoionized gas in the circumgalactic medium (CGM) of dwarf galaxies with $M_* = 10^{6.5-9.5}~M_\odot$ in the nearby Universe ($z<0.3$). We show…

Astrophysics of Galaxies · Physics 2025-03-12 Yakov Faerman , Yong Zheng , Benjamin D. Oppenheimer

Most studies of high-mass star formation focus on massive luminous clumps, but the physical properties of their larger scale environment are poorly known. In this work, we aim at characterising the effects of clustered star formation and…

Astrophysics of Galaxies · Physics 2015-06-12 S. Leurini , F. Wyrowski , F. Herpin , F. van der Tak , R. Guesten , E. F. van Dishoeck

Robust knowledge of molecular gas mass is critical for understanding star formation in galaxies. The H$_{2}$ molecule does not emit efficiently in the cold interstellar medium, hence the molecular gas content of galaxies is typically…

Astrophysics of Galaxies · Physics 2016-10-12 Aditya Togi , J. D. T. Smith

We present results of deep, high velocity resolution ($\sim$1.6 kms$^{-1}$) Giant Meterwave Radio Telescope (GMRT) HI 21 cm-line observations of a sample of extremely faint (M$_B>-$12.5) dwarf irregular galaxies. Unlike previous studies, we…

Astrophysics · Physics 2007-05-23 Ayesha Begum , Jayaram N. Chengalur

The stellar, gaseous and young stellar disks in the LITTLE THINGS sample of nearby dIrrs are fitted with functions to search for correlations between the parameters. We find that the HI radial profiles are generally flatter in the center…

In the last few years new evidence has been presented for the presence of ongoing massive star formation in the outer HI disks of galaxies. These discoveries strongly suggest that precursor molecular gas must also be present in some…

Astrophysics · Physics 2007-05-23 Ronald J. Allen , Rosa Diaz-Miller

We analyze the cool gas in and around 14 nearby galaxies (at $z$$<$0.1) mapped with the SDSS-IV MaNGA survey by measuring absorption lines produced by gas in spectra of background quasars/AGN at impact parameters of 0-25 effective radii…

The latest ALMA and JWST observations provide new information on the birth and evolution of galaxies in the early Universe, at the epoch of reionization. Of particular importance are measurements at redshift $ z > 5$ of their cold-gas…

Astrophysics of Galaxies · Physics 2025-01-15 Benedetta Casavecchia , Umberto Maio , Céline Péroux , Benedetta Ciardi

Low-metallicity dwarf galaxies often show no or little CO emission, despite the intense star formation observed in local samples. Both simulations and resolved observations indicate that molecular gas in low-metallicity galaxies may reside…

We model the observed vertical distribution of the neutral hydrogen (HI) in the faint (M_B ~ -13.7 mag) edge-on dwarf irregular galaxy KK250. Our model assumes that the galaxy consists of axi-symmetric, co-planar gas and stellar discs in…

Astrophysics of Galaxies · Physics 2014-11-18 Narendra Nath Patra , Arunima Banerjee , Jayaram N. Chengalur , Ayesha Begum

Cold gas evolution ties the formation of dark matter halos to the star formation history of the universe. A primary component of cold gas, neutral atomic hydrogen (HI), can be traced by its 21-cm emission line. However, the faintness of…

Astrophysics of Galaxies · Physics 2024-07-12 Tariq Blecher , Roger Deane , Danail Obreschkow , Ian Heywood

Unlike the neutral gas density, which remains largely constant over redshifts of 0 < z < 5, the star formation density exhibits a strong redshift dependence, increasing from the present day before peaking at a redshift of z ~ 2.5. Thus,…

Astrophysics of Galaxies · Physics 2017-10-11 S. J. Curran

We present a study of cold gas absorption from a damped Lyman-$\alpha$ absorber (DLA) at redshift $z_{\rm abs}=1.946$ towards two lensed images of the quasar J144254.78+405535.5 at redshift $z_{\rm QSO} = 2.590$. The physical separation of…

We present one-dimensional models of the hot gas in dark-matter halos, which both predict the existence of cool cores and explain their structure. Our models are directly applicable to semi-analytic models (SAMs) of galaxy formation. We…

Astrophysics of Galaxies · Physics 2015-06-05 Prateek Sharma , Michael McCourt , Ian J. Parrish , Eliot Quataert

Gas-phase complex organic molecules have been detected toward a range of high- and low-mass star-forming regions at abundances which cannot be explained by any known gas-phase chemistry. Recent laboratory experiments show that UV…

Astrophysics of Galaxies · Physics 2015-05-18 Karin I. Oberg , Sandrine Bottinelli , Jes K. Jorgensen , Ewine F. van Dishoeck

Assuming a hydrostatic equilibrium in an HI cloud, the joint Poisson's equation is set up and numerically solved to calculate the expected HI distribution. Unlike previous studies, the cloud is considered to be non-isothermal, and an {\it…

Astrophysics of Galaxies · Physics 2018-08-15 Narendra Nath Patra

We use new and updated gas and dust-corrected SFR surface densities to revisit the integrated star formation law for local "quiescent" spiral, dwarf, and low-surface-brightness galaxies. Using UV-based SFRs with individual IR-based dust…

Astrophysics of Galaxies · Physics 2019-02-12 Mithi A. C. de los Reyes , Robert C. Kennicutt

We present here far-infrared photometry of galaxies in a sample that is relatively unexplored at these wavelengths: low-metallicity dwarf galaxies with moderate star formation rates. Four dwarf irregular galaxies from the…

We present a demographic analysis of integrated star formation and gas properties for a sample of galaxies representative of the overall population at z~0. This research was undertaken in order to characterise the nature of star formation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. S. Bothwell , R. C. Kennicutt , J. C. Lee