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相关论文: Starless Cloud Core L1517B in Envelope Expansion w…

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We analyse synthetic $^{12}$CO, $^{13}$CO, and [CII] emission maps of simulated molecular clouds of the SILCC-Zoom project, which include an on-the-fly evolution of H$_2$, CO, and C$^+$. We use simulations of hydrodynamical and…

星系天体物理 · 物理学 2022-07-12 S. Ebagezio , D. Seifried , S. Walch , P. C. Nürnberger , T. E. Rathjen , T. Naab

Studying the physical and chemical processes leading to the formation of low-mass stars is crucial for understanding the origin of our Sun and the Solar System. In particular, analyzing the emission and absorption lines from molecules is a…

太阳与恒星天体物理 · 物理学 2023-05-24 K. Angelique Kahle , Antonio Hernández-Gómez , Friedrich Wyrowski , Karl M. Menten

In order to study a molecular-cloud-scale chemical composition, we have conducted a mapping spectral line survey toward the Galactic molecular cloud W3(OH), which is one of the most active star forming regions in the Perseus arm, with the…

The $^{13}$CO molecule is often used as a column density tracer in regions where the $^{12}$CO emission saturates. The $^{13}$CO column density is then related to that of $^{12}$CO by a uniform isotopic ratio. A similar approximation is…

星系天体物理 · 物理学 2016-04-25 László Szűcs , Simon C. O. Glover , Ralf S. Klessen

We report the results of molecular line observations toward the l=1.3 deg complex, ananomalous cloud complex in the central molecular zone of the Galaxy. We have taken high resolution maps of the CO J=1-0, HCN J=1-0, HCO+ J=1-0, SiO J=1-0…

天体物理学 · 物理学 2007-05-23 Kunihiko Tanaka , Kazuhisa Kamegai , Makoto Nagai , Tomoharu Oka

Low-mass stars like our Sun begin their evolution within cold (10 K) and dense ($\sim 10^5$ cm$^{-3}$) cores of gas and dust. The physical structure of starless cores is best probed by thermal emission of dust grains. We present a high…

We used the new IRAM 30-m FTS backend to perform an unbiased ~15 GHz wide survey at 3 mm toward the Pipe Nebula young diffuse starless cores. We found an unexpectedly rich chemistry. We propose a new observational classification based on…

星系天体物理 · 物理学 2015-06-03 P. Frau , J. M. Girart , M. T. Beltran

During the gravitational core collapse of a massive progenitor star which may give rise to at least a class of gamma-ray bursts (GRBs) associated with supernovae, a stellar core rapidly passes through a short yet important phase of…

天体物理学 · 物理学 2009-11-13 Yi Cao , Yu-Qing Lou

A series of self-consistent, three-dimensional continuum radiative transfer models are constructed of the pre-protostellar core L1544, with the results compared with existing SCUBA and ISO data. The source is well-fit by a prolate spheroid,…

天体物理学 · 物理学 2009-11-10 Steven D. Doty , Sheila E. Everett , Yancy L. Shirley , Neal J. Evans , Matthew L. Palotti

We present an analysis of the high-resolution Chandra observation of the multiple system, HD 155555 (an RS CVn type binary system, HD 155555 AB, and its spatially resolved low-mass companion HD 155555 C). This is an intriguing system which…

太阳与恒星天体物理 · 物理学 2015-09-23 S. Lalitha , K. P. Singh , S. A. Drake , V. Kashyap

Two scenarios have been proposed for evolution of star forming cores: gravitational fragmentation of larger structures and coalescence of smaller entities which are formed from some instabilities. Here, we turn our attention to the latter…

星系天体物理 · 物理学 2015-05-18 M. Nejad-Asghar

Recently, the Spitzer Space Telescope discovered L1014-IRS, a mid-infrared source with protostellar colors, toward the heretofore "starless" core L1014. We present deep near-infrared observations that show a scattered light nebula extending…

Sulfur is one of the most abundant elements in the Universe, yet the sulfur budget inferred from the observed sulfur-bearing molecules in dense cores is significantly lower than expected. Starless and pre-stellar cores represent the…

星系天体物理 · 物理学 2026-05-14 L. Schöller , S. Spezzano , O. Sipilä , E. I. Makarenko , P. Caselli , H. A. Bunn , S. S. Jensen

We have conducted a mapping spectral line survey toward the Galactic giant molecular cloud W51 in the 3 mm band with the Mopra 22 m telescope in order to study an averaged chemical composition of the gas extended over a molecular cloud…

We present a unified model for molecular core formation and evolution, based on numerical simulations of converging, supersonic flows. Our model applies to star formation in GMCs dominated by large-scale turbulence, and contains four main…

太阳与恒星天体物理 · 物理学 2009-06-25 Hao Gong , Eve C. Ostriker

We present results from the Spitzer Space Telescope and molecular line observations of 9 species toward the dark cloud L43. The Spitzer images and molecular line maps suggest it has a starless core and a Class I protostar evolving in the…

星系天体物理 · 物理学 2014-11-20 Jo-Hsin Chen , Neal J. Evans , Jeong-Eun Lee , Tyler L. Bourke

I present high-resolution column density maps of two molecular clouds having strikingly different star formation rates. To better understand the unusual, massive G216-2.5, a molecular cloud with no massive star formation, the distribution…

太阳与恒星天体物理 · 物理学 2015-06-24 Nia Imara

The Galactic Center regions $-6^\circ \le l \le 6^\circ$ and $-0.8^\circ \le b \le 0.87^\circ$ are surveyed with HCN J=1$-$0 line (88.6 GHz) on a 4$'$ grid with the 14 m telescope at the Taeduk Radio Astronomy Observatory. The data…

天体物理学 · 物理学 2009-10-28 Chang Won Lee

We report radio continuum observations with the Australia Telescope Compact Array of two molecular clouds. The impetus for these observations is a search for synchrotron radiation by cosmic ray secondary electrons/positrons in a region of…

天体物理学 · 物理学 2009-11-13 D. I. Jones , R. J. Protheroe , R. M. Crocker

Young stars form in molecular cores, which are dense condensations within molecular clouds. We have searched for molecular cores traced by $^{13}$CO $J=1\to 0$ emission in the Taurus molecular cloud and studied their properties. Our data…

星系天体物理 · 物理学 2015-06-05 Lei Qian , Di Li , Paul Goldsmith