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相关论文: Dust and hydrogen molecules in the extremely metal…

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Although dust content is usually assumed to depend uniquely on metallicity, recent observations of two extremely metal-poor dwarf galaxies have suggested that this may not always be true. At a similar oxygen abundance of ~ 3% Zsun, the…

星系天体物理 · 物理学 2016-02-17 Raffaella Schneider , Leslie Hunt , Rosa Valiante

We investigate the sources and amount of dust in early galaxies. We discuss dust nucleation in stellar atmospheres using published extended atmosphere models, stellar evolution tracks and nucleation conditions and conclude that the (TPAGB)…

天体物理学 · 物理学 2009-11-07 H L. Morgan , M G. Edmunds

Dust plays crucial roles in galaxy formation and evolution. In the early epoch of galaxy evolution dust is only supplied by supernovae (SNe). With the aid of a new physical model of dust production by SNe, we constructed a model of dust…

天体物理学 · 物理学 2007-05-23 Tsutomu T. Takeuchi

We develop one-zone galaxy formation models in the early Universe, taking into account dust formation and evolution by supernova (SN) explosions. Especially we focus on the time evolution of dust size distribution, because ${\rm H}_{2}$…

We investigate the role of dust in star formation activity of extremely metal-poor blue compact dwarf galaxies (BCDs). Observations suggest that star formation in BCDs occurs in two different regimes: "active" and "passive". The "active"…

天体物理学 · 物理学 2009-11-10 H. Hirashita , L. K. Hunt

The metal deficient (Z = Z_sun/41) Blue Compact Dwarf Galaxy (BCD) SBS 0335-052 was observed with ISOCAM between 5 and 17 mic. With a L_12mic/L_B ratio of 2.15, the galaxy is unexpectedly bright in the mid-infrared for such a…

天体物理学 · 物理学 2009-10-31 T. X. Thuan , M. Sauvage , S. Madden

The relative importance of metals and dust grains in the formation of the first low-mass stars has been a subject of debate. The recently discovered Galactic halo star SDSS J102915+172927 (Caffau et al. 2011) has a mass less than 0.8 Msun…

宇宙学与河外天体物理 · 物理学 2015-06-04 Raffaella Schneider , Kazuyuki Omukai , Marco Limongi , Andrea Ferrara , Ruben Salvaterra , Alessandro Chieffi , Simone Bianchi

We present a study of the early build-up of dust in high redshift galaxies. The study is based on the analysis of 38 Damped Ly alpha systems (DLAs) for which we derive the fraction of iron atoms in dust form, f_{Fe}. The sample is…

天体物理学 · 物理学 2009-11-10 Giovanni Vladilo

The tight relation of star formation with molecular gas indicated by observations and assumed in recent models implies that the efficiency with which galaxies convert their gas into stars depends on gas metallicity. This is because the…

宇宙学与河外天体物理 · 物理学 2015-05-30 Konstantinos Tassis , Nickolay Y. Gnedin , Andrey V. Kravtsov

Stars form out of molecular gas and supply dust grains during their last evolutionary stages; in turn hydrogen molecules (H2) are produced more efficiently on dust grains. Therefore, dust can drastically accelerate H2 formation, leading to…

天体物理学 · 物理学 2009-11-07 H. Hirashita , A. Ferrara

Dusty hyperluminous galaxies in the early universe provide unique environments for studying the role of massive stars in the formation and destruction of dust. At redshifts above ~ 6, when the universe was less than ~ 1 Gyr old, dust could…

天体物理学 · 物理学 2009-11-13 Eli Dwek , Frederic Galliano , Anthony P. Jones

Numerical simulations suggest that the first galaxies are formed in protogalactic halos with virial temperatures >= 10^4 K. It is likely that such halos are polluted with trace amounts of metals produced by the first generation of stars.…

宇宙学与河外天体物理 · 物理学 2015-05-30 M. A. Latif , D. R. G. Schleicher , M. Spaans

We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 0 Band 7 observations of an extremely metal-poor dwarf starburst galaxy in the Local Universe, SBS0335-052 (12+log(O/H)~7.2). With these observations, dust is detected at…

Understanding the formation of the extremely metal poor star SDSS-J102915+172927 is of fundamental importance to improve our knowledge on the transition between the first and second generation of stars in the Universe. In this paper, we…

星系天体物理 · 物理学 2016-12-14 S. Bovino , T. Grassi , D. R. G. Schleicher , R. Banerjee

We present 4-micron ISAAC imaging and spectroscopy of the extremely metal-poor dwarf galaxy SBS 0335-052, aimed at a better understanding of the dust in this low-metallicity galaxy. The 4-micron emission turns out to be very compact,…

天体物理学 · 物理学 2009-11-07 L. K. Hunt , L. Vanzi , T. X. Thuan

Interstellar dust links the formation of the first stars to the rocky planet we inhabit by playing a pivotal role in the cooling and fragmentation of molecular clouds, and catalyzing the formation of water and organic molecules. Despite its…

星系天体物理 · 物理学 2024-10-21 Danial Langeroodi , Jens Hjorth , Andrea Ferrara , Christa Gall

Dust grains in low-metallicity star-forming regions may be responsible for the formation of the first low-mass stars. The minimal conditions to activate dust-induced fragmentation require the gas to be pre-enriched above a critical…

We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI, and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a…

We re-evaluate the roles of different dust sources in dust production as a function of metallicity in late-type dwarf galaxies, with the goal of understanding the relation between dust content and metallicity. The dust content of late-type…

星系天体物理 · 物理学 2015-06-18 Svitlana Zhukovska

Dusty hyperluminous galaxies in the early universe provide unique environments for studying the role of massive stars in the formation and destruction of dust. At redshifts above 6, when the universe was less than 1 Gyr old, dust could have…

天体物理学 · 物理学 2010-11-11 Eli Dwek , Frederic Galliano , Anthony P. Jones
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