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Related papers: The Dynamics of Massive Starless Cores with ALMA

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In this work, we derive the stellar initial mass function (IMF) from the superposition of mass distributions of dense cores, generated through gravoturbulent fragmentation of unstable clumps in molecular clouds (MCs) and growing through…

Solar and Stellar Astrophysics · Physics 2015-05-20 Todor Veltchev , Ralf S. Klessen , Paul C. Clark

The stellar initial mass function (IMF) is critical to our understanding of star formation and the effects of young stars on their environment. On large scales, it enables us to use tracers such as UV or Halpha emission to estimate the star…

Understanding the processes that determine the stellar Initial Mass Function (IMF) is a critical unsolved problem, with profound implications for many areas of astrophysics. In molecular clouds, stars are formed in cores, gas condensations…

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

We carry out an ALMA $\rm N_2D^+$(3-2) and 1.3~mm continuum survey towards 32 high mass surface density regions in seven Infrared Dark Clouds with the aim of finding massive starless cores, which may be the initial conditions for the…

Solar and Stellar Astrophysics · Physics 2017-01-18 Shuo Kong , Jonathan C. Tan , Paola Caselli , Francesco Fontani , Mengyao Liu , Michael J. Butler

Super-sonic turbulence fragments molecular clouds (MC) into a very complex density field with density contrasts of several orders of magnitude. A fraction of the gas is locked into dense and gravitationally bound cores, which collapse as…

Astrophysics · Physics 2007-05-23 Paolo Padoan , AAke Nordlund , Ornolfur Einar Rognvaldsson , Alyssa Goodman

Observations indicate that massive stars form in regions of very high surface density, ~1 g cm^-2. Clusters containing massive stars and globular clusters have a comparable column density. The total pressure in clouds of such a column…

Astrophysics · Physics 2008-11-26 Christopher F. McKee , Jonathan C. Tan

Similar to their low-mass counterparts, massive stars likely form via the collapse of pre-stellar molecular cores. Recent observations suggest that most massive cores are subvirial (i.e., not supported by turbulence) and therefore are…

Solar and Stellar Astrophysics · Physics 2020-01-08 Anna L. Rosen , Pak Shing Li , Qizhou Zhang , Blakesley Burkhart

(abridged) We develop a model which describes the coevolution of the mass function of dense cores and of the IMF in a protocluster clump. In the model, cores injected in the clump evolve under the effect of gas accretion. Accretion onto the…

Astrophysics of Galaxies · Physics 2015-05-14 Sami Dib , Mohsen Shadmehri , Paolo Padoan , G. Maheswar , D. K. Ojha , Fazeleh Khajenabi

The morphology and kinematics of molecular clouds (MCs) are best explained as the consequence of super--sonic turbulence. Super--sonic turbulence fragments MCs into dense sheets, filaments and cores and large low density ``voids'', via the…

Astrophysics · Physics 2008-11-26 Paolo Padoan , AAke Nordlund

The distributions of stars and prestellar cores by mass (initial and dense core mass functions, IMF/DCMF) are among the key factors regulating star formation and are the subject of detailed theoretical and observational studies. Results…

Solar and Stellar Astrophysics · Physics 2016-06-02 Andrei Klishin , Igor Chilingarian

We examine the initial mass functions (IMFs) of stars produced by different molecular core mass functions. Simulations suggest that more massive cores produce more stars, so we propose a model in which the average number of stars formed in…

Astrophysics · Physics 2007-05-23 Simon P. Goodwin , A. P. Whitworth , D. Ward-Thompson

The Infrared Dark Cloud (IRDC) G028.23-00.19 hosts a massive (1,500 Msun), cold (12 K), and 3.6-70 um IR dark clump (MM1) that has the potential to form high-mass stars. We observed this prestellar clump candidate with the SMA (~3.5"…

Three component models of the IMF are made to consider possible origins for the observed relative variations in the numbers of brown dwarfs, solar-to-intermediate mass stars, and high mass stars. Three distinct physical processes are noted.…

Astrophysics · Physics 2009-11-10 Bruce G. Elmegreen

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

We investigate prestellar core formation and accretion based on three-dimensional hydrodynamic simulations. Our simulations represent local $\sim 1$pc regions within giant molecular clouds where a supersonic turbulent flow converges,…

Solar and Stellar Astrophysics · Physics 2015-06-10 Munan Gong , Eve C. Ostriker

Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass from the surrounding cloud material. This process is investigated, using numerical models of self-gravitating molecular cloud…

Astrophysics · Physics 2010-04-06 Ralf Klessen

Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly…

Astrophysics of Galaxies · Physics 2010-11-18 Thomas Peters , Ralf S. Klessen , Mordecai-Mark Mac Low , Robi Banerjee

To characterize the initial conditions for intermediate- to high-mass star formation, we observed two Infrared Dark Clouds (IRDCs) that remain absorption features up to 70mum wavelength, with the PdBI in the 3.23mm dust continuum as well as…

Solar and Stellar Astrophysics · Physics 2015-05-13 Henrik Beuther , Thomas Henning

Context: Stars form in the cold dense cores of interstellar molecular clouds and the detailed knowledge of the spectrum of masses of such cores is clearly a key for the understanding of the origin of the IMF. To date, observations have…

Astrophysics · Physics 2011-06-21 J. Alves , M. Lombardi , C. Lada
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