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Related papers: Complex structure of a proto-brown dwarf

200 papers

We present ALMA continuum and spectral line data at 0.89 mm and 3.2 mm for three disks surrounding young brown dwarfs and very low mass stars in the Taurus star forming region. Dust thermal emission is detected and spatially resolved for…

Earth and Planetary Astrophysics · Physics 2015-06-19 L. Ricci , L. Testi , A. Natta , A. Scholz , I. de Gregorio-Monsalvo , A. Isella

We present Atacama Large Millimeter Array (ALMA) Band 6 observations at 14-20 au spatial resolution of the disk and CO(2-1) outflow around the Class I protostar DG Tau B in Taurus. The disk is very large, both in dust continuum (R$_{\rm…

Solar and Stellar Astrophysics · Physics 2020-02-12 A. de Valon , C. Dougados , S. Cabrit , F. Louvet , L. A. Zapata , D. Mardones

Context. The previously identified source SSTB213 J041757 is a proto brown dwarf candidate in Taurus, which has two possible components A and B. It was found that component B is probably a class 0/I proto brown dwarf associated with an…

Solar and Stellar Astrophysics · Physics 2014-05-08 N. Phan-Bao , C. -F. Lee , P. T. P. Ho , E. L. Martin

As part of the ALMA Large Program "Early Planet Formation in Embedded Disks" (eDisk), 12CO (2 - 1) was observed towards 19 nearby low-mass protostars. Of these objects, 15 sources are found to show molecular outflow emission. Based on their…

CO gas has been detected in $\sim$20 debris discs. We present ALMA observations of the CO-rich HD 121617 debris disc from the ARKS survey. Using high-resolution Band 7 observations of $^{12}CO \ J=3-2$, we analyse local CO line profiles to…

The physical properties of brown dwarf discs, in terms of their shapes and sizes, are still largely unexplored by observations. To what extent brown dwarf discs are similar to scaled-down T Tauri discs is currently unknown, and this work is…

Solar and Stellar Astrophysics · Physics 2017-04-26 A. J. Greenwood , I. Kamp , L. B. F. M. Waters , P. Woitke , W. -F. Thi , Ch. Rab , G. Aresu , M. Spaans

As part of an ALMA survey to study the origin of episodic accretion in young eruptive variables, we have observed the circumstellar environment of the star V2775 Ori. This object is a very young, pre-main sequence object which displays a…

We present ALMA long-baseline observations toward the Class 0 protostar IRAS 16253-2429 (hereafter IRAS 16253) with a resolution down to 0.12" (~15 au). The 1.3 mm dust continuum emission has a deconvolved Gaussian size of 0.16" x 0. 07"…

Astrophysics of Galaxies · Physics 2019-01-30 Tien-Hao Hsieh , Naomi Hirano , Arnaud Belloche , Chin-Fei Lee , Yusuke Aso , Shih-Ping Lai

We present ALMA observations of the 2M1207 system, a young binary made of a brown dwarf with a planetary-mass companion at a projected separation of about 40 au. We detect emission from dust continuum at 0.89 mm and from the $J = 3 - 2$…

Earth and Planetary Astrophysics · Physics 2017-07-05 L. Ricci , P. Cazzoletti , I. Czekala , S. Andrews , D. Wilner , L. Szucs , G. Lodato , L. Testi , I. Pascucci , S. Mohanty , D. Apai , J. Carpenter , B. Bowler

We present ALMA observations of the Class 0 protostar IRAS 04166+2706, obtained as part of the ALMA large program Early Planet Formation in Embedded Disks (eDisk). These observations were made in the 1.3 mm dust continuum and molecular…

Context: The R CrA cloud hosts a handful of Class 0/I low-mass young stellar objects. The chemistry and physics at scales $>500$ AU in this cloud are dominated by the irradiation from the nearby Herbig Be star R CrA. The luminous…

We present detailed analysis of high-resolution C18O (2-1), SO (88-77), CO (3-2) and DCO+ (3-2) data obtained by the Atacama Large Millimeter/sub-millimeter Array (ALMA) towards a Class 0 Keplerian circumbinary disk around VLA1623A, which…

Solar and Stellar Astrophysics · Physics 2020-05-06 Cheng-Han Hsieh , Shih-Ping Lai , Pou-Ieng Cheong , Chia-Lin Ko , Zhi-Yun Li , Nadia M. Murillo

Young circumstellar disks that are still embedded in dense molecular envelopes may differ from their older counterparts, but are historically difficult to study because emission from a disk can be confused with envelope or outflow emission.…

Solar and Stellar Astrophysics · Physics 2015-05-28 Gregory J. Herczeg , Joanna M. Brown , Ewine F. van Dishoeck , Klaus M. Pontoppidan

The formation mechanism of brown dwarfs (BDs) is one of the long-standing problems in star formation because the typical Jeans mass in molecular clouds is too large to form these substellar objects. To answer this question, it is crucial to…

Astrophysics of Galaxies · Physics 2016-07-27 Tien-Hao Hsieh , Shih-Ping Lai , Arnaud Belloche , Friedrich Wyrowski

Context: Because it is viewed simply edge-on, the HH212 protostellar system is an ideal laboratory for studying the interplay of infall, outflow, and rotation in the earliest stages of low-mass star formation. Aims: We wish to exploit the…

Solar and Stellar Astrophysics · Physics 2015-06-22 C. Codella , S. Cabrit , F. Gueth , L. Podio , S. Leurini , R. Bachiller , A. Gusdorf , B. Lefloch , B. Nisini , M. Tafalla , W. Yvart

HH 212 is a nearby (400 pc) Class 0 protostellar system recently found to host a "hamburger"-shaped dusty disk with a radius of ~ 60 AU, deeply embedded in an infalling-rotating flattened envelope. We have spatially resolved this…

Astrophysics of Galaxies · Physics 2017-07-05 Chin-Fei Lee , Zhi-Yun Li , Paul T. P. Ho , Naomi Hirano , Qizhou Zhang , Hsien Shang

Precise estimates of protostellar masses are crucial to characterize the formation of stars of low masses down to brown-dwarfs (BDs; M* < 0.08 Msun). The most accurate estimation of protostellar mass uses the Keplerian rotation in the…

We present ALMA continuum and spectral line observations of the young Brown Dwarf rho-Oph 102 at about 0.89 mm and 3.2 mm. We detect dust emission from the disk at these wavelengths and derive an upper limit on the radius of the dusty disk…

Solar and Stellar Astrophysics · Physics 2015-06-12 L. Ricci , L. Testi , A. Natta , A. Scholz , I. de Gregorio-Monsalvo

Complex organic molecules (COMs) in young stellar objects (YSOs) have attracted significant attention in recent years due to their potential connection to pre-biotic chemistry and their utility as tracers of warm or shocked gas components.…

The collapse of the protostellar envelope results in the growth of the protostar and the development of a protoplanetary disk, playing a critical role during the early stages of star formation. Characterizing the gas infall in the envelope…

Solar and Stellar Astrophysics · Physics 2020-03-11 Y. -L. Yang , N. J. Evans , A. Smith , J. -E. Lee , J. J. Tobin , S. Terebey , H. Calcutt , J. K. Jorgensen , J. D. Green , T. L. Bourke