English
Related papers

Related papers: Episodic infall towards a compact disk in B335?

200 papers

Protostellar outflows often present a knotty appearance, providing evidence of sporadic accretion in stellar mass growth. To understand the direct relation between mass accretion and ejection, we analyze the contemporaneous accretion…

Solar and Stellar Astrophysics · Physics 2023-12-12 Chul-Hwan Kim , Jeong-Eun Lee , Carlos Contreras Peña , Doug Johnstone , Gregory J. Herczeg , John J. Tobin , Neal J. Evans

We have conducted ALMA observations in the 1.3 mm continuum and 12CO (2-1), C18O (2-1) and SO (5_6-4_5) lines toward L1489 IRS, a Class I protostar surrounded by a Keplerian disk and an infalling envelope. The Keplerian disk is clearly…

The massive young stellar object S255IR NIRS3 embedded in the star forming core SMA1 has been recently observed with a luminosity burst, which is conjectured as a disc-mediated variable accretion event. In this context, it is imperative to…

Astrophysics of Galaxies · Physics 2020-12-09 Sheng-Yuan Liu , Yu-Nung Su , Igor Zinchenko , Kuo-Song Wang , Dominique M. -A. Meyer , Yuan Wang , I-Ta Hsieh

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

The filamentary nature of accretion streams found around embedded sources suggest that protostellar disks experience heterogenous infall from the star-forming environment, consistent with the accretion behavior onto star-forming cores in…

Earth and Planetary Astrophysics · Physics 2022-04-06 Aleksandra Kuznetsova , Jaehan Bae , Lee Hartmann , Mordecai-Mark Mac Low

We present a detailed study of the massive star-forming region G35.2-0.74N with ALMA 1.3 mm multi-configuration observations. At 0.2" (440 au) resolution, the continuum emission reveals several dense cores along a filamentary structure,…

Spiral arms, rings and large scale asymmetries are structures observed in high resolution observations of protoplanetary disks, and it appears that some of the disks showing spiral arms in scattered light also show asymmetries in…

Earth and Planetary Astrophysics · Physics 2018-11-21 P. Cazzoletti , E. F. van Dishoeck , P. Pinilla , M. Tazzari , S. Facchini , N. van der Marel , M. Benisty , A. Garufi , L. Pérez

We report ALMA observations of NGC 1333 IRAS 4A, a young low-mass protostellar binary, referred as 4A1 and 4A2. With multiple H$_2$CO transitions and HNC (4$-$3) observed at a resolution of 0.25" ($\sim$70 au), we investigate the gas…

Solar and Stellar Astrophysics · Physics 2020-01-08 Yu-Nung Su , Sheng-Yuan Liu , Zhi-Yun Li , Chin-Fei Lee , Naomi Hirano , Shigehisa Takakuwa , I-Ta Hsieh

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

Observations of interstellar material infalling onto star- and planet-forming systems have become increasingly common thanks to recent advancements in radio interferometry. These structures replenish disks with fresh material, have the…

We present ALMA Band 6 observations of the CO(2-1), HCN(3-2), and HCO$^{+}$(3-2) lines in the nearby radio galaxy / brightest cluster galaxy (BCG) of NGC 1275 with the spatial resolution of $\sim20$ pc. In the previous observations, CO(2-1)…

Astrophysics of Galaxies · Physics 2019-10-09 H. Nagai , K. Onishi , N. Kawakatu , Y. Fujita , M. Kino , Y. Fukazawa , J. Lim , W. Forman , J. Vrtilek , K. Nakanishi , H. Noda , K. Asada , K. Wajima , Y. Ohyama , L. David

We have carried out radiative transfer calculations of infalling, dusty envelopes surrounding embedded protostars to understand the observed properties of the recently identified ``Class 0'' sources. To match the far-infrared peaks in the…

Astrophysics · Physics 2009-10-31 Ray Jayawardhana , Lee Hartmann , Nuria Calvet

During the early stages of star formation, accretion processes such as infall from the envelope and molecular streamers, and ejection of matter through winds and jets take place simultaneously. The Class 0/I binary [BHB2007] 11 shows…

We present subarcsecond resolution dust continuum observations of the protostellar collapse candidate B335 made with the IRAM Plateau de Bure Interferometer at wavelengths of 1.2 and 3.0 mm. These observations probe to < 100 AU size scales…

Astrophysics · Physics 2009-11-10 Daniel W. A. Harvey , David J. Wilner , Philip C. Myers , Mario Tafalla

In recent years spiral structures have been seen in scattered light observations and signs of vortices in millimeter images of protoplanetary disks, both probably linked with the presence of planets. We present ALMA Band 7 (335 GHz or 0.89…

Earth and Planetary Astrophysics · Physics 2016-12-14 Nienke van der Marel , Paolo Cazzoletti , Paola Pinilla , Antonio Garufi

A large fraction of planet-forming disks observed with ALMA show faint CO emission, often interpreted as strong CO depletion. However, faint emission may also arise from spatially unresolved disks, whose sizes are overestimated, making them…

Pairs of azimuthal intensity decrements at near symmetric locations have been seen in a number of protoplanetary disks. They are most commonly interpreted as the two shadows cast by a highly misaligned inner disk. Direct evidence of such an…

Non-ideal magnetohydrodynamic effects that rule the coupling of the magnetic field to the circumstellar gas during the low-mass star formation process depend heavily on the local physical conditions, such as the ionization fraction of the…

Subarcsecond-resolution images of the rotational line emissions of CS and c-C$_3$H$_2$ obtained toward the low-mass protostar IRAS 04368$+$2557 in L1527 with the Atacama Large Millimeter/submillimeter Array are investigated to constrain the…

Solar and Stellar Astrophysics · Physics 2016-04-28 Yoko Oya , Nami Sakai , Bertrand Lefloch , Ana López-Sepulvre , Yoshimasa Watanabe , Cecilia Ceccarelli , Satoshi Yamamoto

We present the detection of infall, rotation and outflow kinematic signatures towards both a protostellar source, VLA 1623 and what was initially thought to be a pre-protostellar core, SM1N, in the rho-Ophiuchus A region. The kinematic…

Astrophysics · Physics 2011-02-11 Gopal Narayanan , Daniel W. Logan