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Related papers: The accretion luminosity of Class I protostars

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Periodic increases in luminosity arising from variable accretion rates have been predicted for some close pre-main sequence binary stars as they grow from circumbinary disks. The phenomenon is known as "pulsed accretion" and can affect the…

Solar and Stellar Astrophysics · Physics 2015-06-12 James Muzerolle , Elise Furlan , Kevin Flaherty , Zoltan Balog , Robert Gutermuth

In this Letter we present a theoretical scenario to explain the steep correlation between disk accretion rates and stellar masses observed in pre-main sequence stars. We show that the correlations and spread observed in the two best studied…

Astrophysics · Physics 2009-11-11 C. P. Dullemond , A. Natta , L. Testi

Our knowledge of circumstellar disks has traditionally been based on studies of dust. However, gas dominates the disk mass and its study is key to understand the star and planet formation process. Spitzer can access gas emission lines in…

Identified as extinction features against the bright Galactic mid-infrared background, infrared dark clouds (IRDCs) are thought to harbor the very earliest stages of star and cluster formation. In order to better characterize the properties…

Solar and Stellar Astrophysics · Physics 2015-05-18 J. M. Rathborne , J. M. Jackson , E. T. Chambers , I. Stojimirovic , R. Simon , R. Shipman , W. Frieswijk

We use a suite of cosmological hydrodynamic simulations to quantify the accretion rates of baryons into dark matter halos and the resulting baryon mass fractions, as a function of halo mass, redshift, and baryon type (including cold and hot…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 C. -A. Faucher-Giguere , D. Keres , C. -P. Ma

We present the first spectrum of a highly veiled, strongly accreting protostar which shows photospheric absorption features and demonstrates the stellar nature of its central core. We find the spectrum of the luminous (L_bol = 10 L_sun)…

Astrophysics · Physics 2009-11-07 Thomas P. Greene , Charles J. Lada

We construct detailed vertical structure models of irradiated accretion disks around T Tauri stars with interstellar medium dust uniformly mixed with gas. The dependence of the structure and emission properties on mass accretion rate,…

Astrophysics · Physics 2009-10-31 Paola D'Alessio , Nuria Calvet , Lee Hartmann , Susana Lizano , Jorge Canto

One possible scenario for the formation of massive black holes (BHs) in the early Universe is from the direct collapse of primordial gas in atomic-cooling dark matter haloes in which the gas is unable to cool efficiently via molecular…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Jarrett L. Johnson , Sadegh Khochfar , Thomas H. Greif , Fabrice Durier

Context: Dust grains are key components of the interstellar medium and play a central role in star formation, acting as catalysts for chemical reactions and as building blocks of planets. Extinction curves are essential for characterizing…

This chapter reviews progress in the field of massive star formation. It focuses on evidence for accretion and current models that invoke high accretion rates. In particular it is noted that high accretion rates will cause the massive young…

Astrophysics · Physics 2016-01-27 Melvin G. Hoare , Jose Franco

We present initial result of a large spectroscopic survey aimed at measuring the timescale of mass accretion in young, pre-main-sequence stars in the spectral type range K0 - M5. Using multi-object spectroscopy with VIMOS at the VLT we…

Solar and Stellar Astrophysics · Physics 2015-05-14 D. Fedele , M. E. van den Ancker , Th. Henning , R. Jayawardhana , J. M. Oliveira

To date, there is no explanation as to why disc-tracing CO first overtone (or `bandhead') emission is not a ubiquitous feature in low- to medium-resolution spectra of massive young stellar objects, but instead is only detected toward…

Solar and Stellar Astrophysics · Physics 2018-04-25 J. D. Ilee , R. D. Oudmaijer , H. E. Wheelwright , R. Pomohaci

We report on simulations of the formation of the first stars in the Universe, where we identify regions of hot atomic gas (fH2 < 10-6) at densities above 10-14 g/cc, heated to temperatures ranging between 3000 and 8000 K. Within this…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Matthew J. Turk , Michael L. Norman , Tom Abel

Aims: The JWST program JOYS (JWST Observations of Young protoStars) aims at characterizing the physical and chemical properties of young high- and low-mass star-forming regions, in particular the unique mid-infrared diagnostics of the…

During the formation of the large scale structure of the Universe, matter accretes onto high density peaks. Accreting collisionless dark matter (DM) forms caustics around them, while accreting collisional baryonic matter (BM) forms…

Astrophysics · Physics 2015-06-24 Dongsu Ryu , Hyesung Kang

We have assembled a sample of high spatial resolution far-UV (Hubble Space Telescope Advanced Camera for Surveys Solar Blind Channel) and Halpha (Maryland-Magellan Tunable Filter) imaging for 15 cool core galaxy clusters. These data provide…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael McDonald , Sylvain Veilleux , David S. N. Rupke , Richard Mushotzky , Christopher Reynolds

Context: While class II pre-main-sequence (PMS) stars have already accreted most of their mass, the continued inflow of fresh material via Bondi-Hoyle accretion acts as an additional mass reservoir for their circumstellar disks. This may…

Solar and Stellar Astrophysics · Physics 2025-03-03 Veli-Matti Pelkonen , Paolo Padoan , Mika Juvela , Troels Haugbølle , Åke Nordlund

Recent high-angular resolution (40 mas) ALMA observations at 1.14 mm resolve a compact (R~200 au) flattened dust structure perpendicular to the HH 80-81 jet emanating from the GGD 27-MM1 high-mass protostar, making it a robust candidate for…

Using the ISOPHOT Serendipity Survey (ISOSS) at 170um a sample of galactic star-forming regions exhibiting very cold dust temperatures (< 20 K) and high masses (> 100 M_sun) has been established. We characterise the star-forming content of…

Astrophysics · Physics 2010-05-19 M. Hennemann , S. M. Birkmann , O. Krause , D. Lemke
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