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Related papers: The structure and stability of molecular cloud cor…

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We present the first search for spinning dust emission from a sample of 34 Galactic cold cores, performed using the CARMA interferometer. For each of our cores we use photometric data from the Herschel Space Observatory to constrain N_{H},…

We examine heating and cooling in protostellar disks using 3-D radiation-MHD calculations of a patch of the Solar nebula at 1 AU, employing the shearing-box and flux-limited radiation diffusion approximations. The disk atmosphere is ionized…

Earth and Planetary Astrophysics · Physics 2015-05-27 S. Hirose , N. J. Turner

We have mapped six molecular cloud cores in the Orion A giant molecular cloud (GMC), whose kinetic temperatures range from 10 to 30 K, in CCS and N2H+ with Nobeyama 45 m radio telescope to study their chemical characteristics. We identified…

We present combined VLA and Green Bank Telescope images of \ammonia\ inversion transitions (1,1) and (2,2) toward OMC2 and OMC3. We focus on the relatively quiescent Orion cores, which are away from the Trapezium cluster and have no sign of…

Astrophysics of Galaxies · Physics 2015-06-05 D. Li , J. Kauffmann , Q. Zhang , W. Chen

Our understanding of the physical and chemical structure of pre-stellar cores, the simplest star-forming sites, has significantly improved since the last IAU Symposium on Astrochemistry (South Korea, 1999). Research done over these years…

Astrophysics · Physics 2015-06-24 M. Tafalla

Cosmic rays are an important source of heating in the interstellar medium, in particular in dense molecular cloud cores shielded from the external ultraviolet radiation field. The limits placed on the cosmic-ray ionization rate from…

Solar and Stellar Astrophysics · Physics 2015-02-12 Daniele Galli , Marco Padovani

We present an analysis of 20 galaxy clusters observed with the Chandra X-ray satellite, focussing on the temperature structure of the intracluster medium and the cooling time of the gas. Our sample is drawn from a flux-limited catalogue but…

Astrophysics · Physics 2009-11-11 Alastair J. R. Sanderson , Trevor J. Ponman , Ewan O'Sullivan

We present new results on CO depletion in a sample of nearby pre-stellar cores, based on observations of the millimeter C17O and C18O lines and the 1.3 mm dust emission with the IRAM 30m telescope. In most cases, the distribution of CO is…

In giant molecular clouds (GMCs), shocks driven by converging turbulent flows create high-density, strongly-magnetized regions that are locally sheetlike. In previous work, we showed that within these layers, dense filaments and embedded…

Astrophysics of Galaxies · Physics 2015-10-21 Che-Yu Chen , Eve C. Ostriker

The improvements of the knowledge of the seismic structure of the inner core and the complexities thereby revealed ask for a dynamical origin. Sub-solidus convection was one of the early suggestions to explain the seismic anisotropy, but it…

Geophysics · Physics 2014-08-12 Stéphane Labrosse

The Central Molecular Zone (CMZ) at the center of our Galaxy is the best template to study star formation processes under extreme conditions, similar to those in high-redshift galaxies. We observed on-the-fly maps of para-H$_{2}$CO…

Astrophysics of Galaxies · Physics 2016-11-09 K. Immer , J. Kauffmann , T. Pillai , A. Ginsburg , K. M. Menten

Context. Using observations to deduce dust properties, grain size distribution, and physical conditions in molecular clouds is a highly degenerate problem. Aims. The coreshine phenomenon, a scattering process at 3.6 and 4.5 $\mu$m that…

Recent years have seen excellent progress in modeling the entrainment of T $\sim$ $10^4$K atomic gas in galactic winds. However, the entrainment of cool, dusty T $\sim$ 10-100K molecular gas, which is also observed outflowing at high…

Astrophysics of Galaxies · Physics 2024-04-24 Zirui Chen , S. Peng Oh

Measurement of chemical and kinematic structures in prestellar cores is essential for better understanding the star formation process. Here, we study the three prestellar cores (TMC-1C, L1544, and TMC-1) of the Taurus molecular cloud by…

Astrophysics of Galaxies · Physics 2022-08-31 Atanu Koley

We calculate the evolution of cloud cores embedded in different envelopes to investigate environmental effects on the mass accretion rate onto protostars. As the initial state, we neglect the magnetic field and cloud rotation, and adopt…

Solar and Stellar Astrophysics · Physics 2023-01-11 Shingo Nozaki , Masahiro N. Machida

[Abridged] $Context.$ Pre-stellar cores are centrally concentrated starless cores on the verge of star formation and they represent the initial conditions for star and planet formation. Pre-stellar cores host an active organic chemistry and…

Astrophysics of Galaxies · Physics 2025-11-12 P. Caselli , S. Spezzano , E. Redaelli , J. Harju , D. Arzoumanian , F. Lique , O. Sipilä , J. E. Pineda , E. Wirström , F. Wyrowski , A. Belloche

A fraction of the dense cores within a turbulent molecular cloud will eventually collapse to form stars. Identifying the physical criteria for instability and analyzing critical core properties is therefore necessary to star formation…

Astrophysics of Galaxies · Physics 2025-07-16 Sanghyuk Moon , Eve C. Ostriker

We present new computations of the equilibrium and non-equilibrium cooling efficiencies and ionization states for low-density radiatively cooling gas containing cosmic abundances of the elements H, He, C, N, O, Ne, Mg, Si, S, and Fe. We…

Astrophysics · Physics 2009-11-11 Orly Gnat , Amiel Sternberg

Our current understanding of the physical conditions in the inner regions of protoplanetary discs is becoming increasingly challenged by the more detailed observational and theoretical explorations. Calculation of dust temperature is one of…

Solar and Stellar Astrophysics · Physics 2011-12-05 Dejan Vinkovic

We present a new analytical three-parameter formula to fit observed column density profiles of prestellar cores. It represents a line-of-sight integral through a spherically symmetric or disc-like isothermal cloud. The underlying model…

Solar and Stellar Astrophysics · Physics 2013-08-19 Wolf B. Dapp , Shantanu Basu
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