English
Related papers

Related papers: Star formation in metal-poor gas clouds

200 papers

We review recent advances in the analytical and numerical modeling of the star formation rate in molecular clouds and discuss the available observational constraints. We focus on molecular clouds as the fundamental star formation sites,…

Population III stars are believed to have been more massive than typical stars today and to have formed in relative isolation. The thermodynamic impact of metals is expected to induce a transition leading to clustered, low-mass Population…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Chalence Safranek-Shrader , Milos Milosavljevic , Volker Bromm

The chemical structure of neutral clouds in low metallicity environments is examined with particular emphasis on the H to H_2 and C+ to CO transitions. We observed near-IR H_2 lines and the CO J=1-0 line from 30 Doradus and N159/N160 in the…

Astrophysics · Physics 2014-10-13 Soojong Pak , D. T. Jaffe , Ewine F. van Dishoeck , L. E. B. Johansson , R. S. Booth

We present here a three-dimesional hydrodynamical simulation for star formation. Our aim is to explore the effect of the metal-line cooling on the thermodynamics of the star-formation process. We explore the effect of changing the…

Astrophysics of Galaxies · Physics 2018-11-26 P. Fibla , S. Bovino , R. Riaz , V. B. Díaz , C. Olave , S. Vanaverbeke , D. R. G. Schleicher

Stars in galaxies form in giant molecular clouds that coalesce when the atomic hydrogen is converted into molecules. There are currently two dominant models for what property of the galactic disk determines its molecular fraction: either…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Michele Fumagalli , Mark R. Krumholz , Leslie K. Hunt

The thermal and fragmentation properties of star-forming clouds have important consequences on the corresponding characteristic stellar mass. The initial composition of the gas within these clouds is a record of the nucleosynthetic products…

Astrophysics · Physics 2009-11-11 Raffaella Schneider , Kazuyuki Omukai , Akio Inoue , Andrea Ferrara

We investigate the stellar populations and molecular gas properties of a star-forming region within the dwarf irregular (dIrr) galaxy WLM. Low-metallicity dIrrs like WLM offer a valuable window into star formation in environments that are…

We describe a phenomenological model for molecular hydrogen formation suited for applications in galaxy formation simulations, which includes on-equilibrium formation of molecular hydrogen on dust and approximate treatment of both its…

Astrophysics · Physics 2010-12-28 Nickolay Y. Gnedin , Konstantinos Tassis , Andrey V. Kravtsov

In the context of the star formation through the fragmentation of an extremely metal-deficient protogalactic cloud, the gravitational collapse of filamentary gas clouds is explored with H$_2$ and HD chemistry. It is found by 1D…

Astrophysics · Physics 2016-01-27 Fumitaka Nakamura , Masayuki Umemura

We investigate the dependence of stellar properties on the initial mean density of the molecular cloud in which stellar clusters form using radiation hydrodynamical simulations that resolve the opacity limit for fragmentation. We have…

Solar and Stellar Astrophysics · Physics 2018-06-05 Michael O. Jones , Matthew. R. Bate

Cosmological numerical simulations of galaxy evolution show that accretion of metal-poor gas from the cosmic web drives the star formation in galaxy disks. Unfortunately, the observational support for this theoretical prediction is still…

Astrophysics of Galaxies · Physics 2017-05-31 J. Sanchez Almeida

Extremely metal-poor galaxies with metallicity below 10% of the solar value in the local universe are the best analogues to investigating the interstellar medium at a quasi-primitive environment in the early universe. In spite of the…

Astrophysics of Galaxies · Physics 2017-01-04 Yong Shi , Junzhi Wang , Zhi-Yu Zhang , Yu Gao , Cai-Na Hao , Xiao-Yang Xia , Qiusheng Gu

Metals are thought to have profound effects on the internal structures of molecular clouds in which stars are born. The absence of metals is expected to prevent gas from efficient cooling and fragmentation in theory. However, this effect…

Astrophysics of Galaxies · Physics 2020-04-15 Yong Shi , Junzhi Wang , Zhi-Yu Zhang , Qizhou Zhang , Yu Gao , Luwenjia Zhou , Qiusheng Gu , Keping Qiu , Xiao-Yang Xia , Cai-Na Hao , Yanmei Chen

The relations between star formation and properties of molecular clouds are studied based on a sample of star forming regions in the Galactic Plane. Sources were selected by having radio recombination lines to provide identification of…

Solar and Stellar Astrophysics · Physics 2017-03-08 Nalin Vutisalchavakul , Neal J. Evans , Mark Heyer

We present numerical simulations to describe the evolution of pre-Galactic clouds in a model which is motivated by cold dark matter simulations of hierarchical galaxy formation. We adopt a SN-induced star-formation mechanism within a model…

Astrophysics · Physics 2007-05-23 Lamya Saleh , Timothy C. Beers , Grant J. Mathews

Comparison of the ISM properties of a wide range of metal-poor galaxies with normal metal-rich galaxies reveals striking differences. We find that the combination of the low dust abundance and the active star formation results in a very…

Astrophysics of Galaxies · Physics 2017-01-11 Suzanne C. Madden , Diane Cormier , Aurelie Remy-Ruyer

In this paper we investigate the level of star formation activity within nearby molecular clouds. We employ a uniform set of infrared extinction maps to provide accurate assessments of cloud mass and structure and compare these with…

Astrophysics of Galaxies · Physics 2015-05-19 Charles J. Lada , Marco Lombardi , João F. Alves

Observations of both star-forming regions and young, gas-free stellar associations indicate that most nearby molecular clouds form stars only over a short time span before dispersal; large-scale flows in the diffuse interstellar medium have…

Astrophysics · Physics 2008-11-26 Lee Hartmann , Javier Ballesteros-Paredes , Edwin A. Bergin

We study the formation of very metal-poor stars under protostellar radiative feedback effect. We use cosmological simulations to identify low-mass dark matter halos and star-forming gas clouds within them. We then follow protostar formation…

Astrophysics of Galaxies · Physics 2021-04-23 Hajime Fukushima , Takashi Hosokawa , Gen Chiaki , Kazuyuki Omukai , Naoki Yoshida , Rolf Kuiper

In most galaxies like the Milky Way, stars form in clouds of molecular gas. Unlike the CO emission that traces the bulk of molecular gas, the rotational transitions of HCN and CS molecules mainly probe the dense phase of molecular gas,…

Astrophysics of Galaxies · Physics 2020-05-20 Kaiyi Du , Yong Shi , Zhi-Yu Zhang , Junzhi Wang , Yu Gao
‹ Prev 1 3 4 5 6 7 10 Next ›