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Related papers: Star formation in metal-poor gas clouds

200 papers

Dust grains coagulate into larger aggregates in dense gas. This changes their size distribution and possibly affects the thermal evolution of star-forming clouds. We here investigate dust coagulation in collapsing pre-stellar cores with…

Astrophysics of Galaxies · Physics 2015-05-13 Hiroyuki Hirashita , Kazuyuki Omukai

The discovery of a low-mass star with such low metallicity as < 4.5x10^{-5} Z_sun reveals the critical role of dust in the formation of extremely metal-poor stars. In this paper we explore the effect of the growth of dust grains through…

Solar and Stellar Astrophysics · Physics 2015-06-11 Takaya Nozawa , Takashi Kozasa , Ken'ichi Nomoto

Context. Stellar feedback regulates star formation and shapes the interstellar medium, yet its role during the collapse of molecular clouds remains uncertain over a wide range of initial conditions. Aims. We explore how stellar winds and…

Astrophysics of Galaxies · Physics 2026-05-13 S. Jiménez , D. Kománek , R. Wünsch , J. Palouš , S. Ehlerová , S. Martínez-González , A. Srbljanović

The apparent lack of cold molecular gas in blue compact dwarf (BCD) galaxies is at variance with their intense star-formation episode. The CO molecule, often used a tracer of H2 through a conversion function, is selectively photodissociated…

Astrophysics of Galaxies · Physics 2020-01-08 Vianney Lebouteiller

We investigate the condition for the formation of low-mass second-generation stars in the early universe. It has been proposed that gas cooling by dust thermal emission can trigger fragmentation of a low-metallicity star-forming gas cloud.…

We present the first numerical simulations that self-consistently follow the formation of dense molecular clouds in colliding flows. Our calculations include a time-dependent model for the H2 and CO chemistry that runs alongside a detailed…

Astrophysics of Galaxies · Physics 2015-06-04 Paul C. Clark , Simon C. O. Glover , Ralf S. Klessen , Ian A. Bonnell

We study the influence of gas metallicity, turbulence, and non-equilibrium chemistry on the evolution of the two-phase interstellar medium (warm and cold atomic phases), and thereby constrain the initial conditions for star formation…

Astrophysics of Galaxies · Physics 2015-05-27 S. Walch , R. Wuensch , A. Burkert , S. Glover , A. Whitworth

[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…

Star formation activity in molecular clouds is often found to be correlated with the amount of material above a column density threshold of $\sim 10^{22} \, {\rm cm^{-2}}$. Attempts to connect this column density threshold to a ${\it…

Astrophysics of Galaxies · Physics 2023-10-11 F. D. Priestley , P. C. Clark , S. C. O. Glover , S. E. Ragan , O. Fehér , L. R. Prole , R. S. Klessen

Using the Atacama Large Millimeter/submillimeter Array, we have made the first high spatial and spectral resolution observations of the molecular gas and dust in the prototypical blue compact dwarf galaxy II Zw 40. The CO(2-1) and CO(3-2)…

Astrophysics of Galaxies · Physics 2016-09-07 Amanda A. Kepley , Adam K. Leroy , Kelsey E. Johnson , Karin Sandstrom , C. -H. Rosie Chen

We study the molecular content and the star formation efficiency of 21 Blue Compact Dwarfs (BCDs). We present CO(1-0) and (2-1) observations, further supplemented with additional CO measurements and multiwavelength ancillary data from the…

Astrophysics of Galaxies · Physics 2016-03-16 Ricardo Amorín , C. Muñoz-Tuñón , J. A. L. Aguerri , P. Planesas

We report the statistical properties of stars and brown dwarfs obtained from four radiation hydrodynamical simulations of star cluster formation, the metallicities of which span a range from 1/100 to 3 times the solar value. Unlike previous…

Solar and Stellar Astrophysics · Physics 2019-01-15 Matthew R. Bate

We demonstrate that the observationally inferred rapid onset of star formation after parental molecular clouds have assembled can be achieved by flow-driven cloud formation of atomic gas, using our previous three-dimensional numerical…

Astrophysics · Physics 2009-11-13 Fabian Heitsch , Lee Hartmann

We study relations between stellar mass, star formation and gas-phase metallicity in a sample of 177,071 unique emission line galaxies from the SDSS-DR7, as well as in a sample of 43,767 star forming galaxies at z=0 from the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Robert M. Yates , Guinevere Kauffmann , Qi Guo

Tracing molecular hydrogen content with carbon monoxide in low-metallicity galaxies has been exceedingly difficult. Here we present a new effort, with IRAM 30-m observations of 12CO(1-0) of a sample of 8 dwarf galaxies having oxygen…

Astrophysics of Galaxies · Physics 2015-11-04 L. K. Hunt , S. Garcia-Burillo , V. Casasola , P. Caselli , F. Combes , C. Henkel , A. Lundgren , R. Maiolino , K. M. Menten , L. Testi , A. Weiss

If a significant fraction of metals is in dust, star-forming cores with metallicity higher than a critical value ~10^{-6}-10^{-5}Z_sun are able to fragment by dust cooling, thereby producing low-mass cores. Despite being above the critical…

Astrophysics · Physics 2009-11-13 T. Tsuribe , K. Omukai

We implement physically motivated recipes for partitioning cold gas into different phases (atomic, molecular, and ionized) in galaxies within semi-analytic models of galaxy formation based on cosmological merger trees. We then model the…

Astrophysics of Galaxies · Physics 2015-09-30 Rachel S. Somerville , Gergö Popping , Scott C. Trager

Recent discoveries of carbon-enhanced metal-poor stars like SMSS J031300.36-670839.3 provide increasing observational insights into the formation conditions of the first second-generation stars in the Universe, reflecting the chemical…

Solar and Stellar Astrophysics · Physics 2015-06-22 S. Bovino , T. Grassi , D. R. G. Schleicher , M. A. Latif

The formation of supermassive stars has generally been studied under the assumption of rapid accretion of pristine metal-free gas. Recently it was found, however, that gas enriched to metallicities up to $Z \sim 10^{-3}$ Z$_{\odot}$ can…

Astrophysics of Galaxies · Physics 2020-09-16 John A. Regan , Zoltán Haiman , John H. Wise , Brian W. O'Shea , Michael L. Norman

We study the connection of star formation to atomic (HI) and molecular hydrogen (H$_2$) in isolated, low metallicity dwarf galaxies with high-resolution ($m_{\rm gas}$ = 4 M$_\odot$, $N_{\rm ngb}$ = 100) SPH simulations. The model includes…

Astrophysics of Galaxies · Physics 2016-03-23 Chia-Yu Hu , Thorsten Naab , Stefanie Walch , Simon C. O. Glover , Paul C. Clark