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相关论文: Stringent Limits on the Polarized Submillimeter Em…

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We have detected the T~Tauri star, DO Tauri, in a 0.6$''$-resolution VLA map of 43.3 GHz ($\lambda$ = 7 mm) continuum emission. The 43 GHz flux density lies on the same power-law slope defined by 89 to 232 GHz measurements, F$_\nu$ $\propto…

天体物理学 · 物理学 2009-10-28 D. W. Koerner , C. J. Chandler , A. I. Sargent

We present 870 $\mu$m ALMA polarization observations of thermal dust emission from the iconic, edge-on debris disk $\beta$ Pic. While the spatially resolved map does not exhibit detectable polarized dust emission, we detect polarization at…

Anomalies in the abundance measurements of short lived radionuclides in meteorites indicate that the protosolar nebulae was irradiated by a high amount of energetic particles (E$\gtrsim$10 MeV). The particle flux of the contemporary Sun…

太阳与恒星天体物理 · 物理学 2017-07-12 Ch. Rab , M. Güdel , M. Padovani , I. Kamp , W. -F. Thi , P. Woitke , G. Aresu

We present a sub-arcsecond resolution survey of the 340 GHz dust continuum emission from 50 nearby protoplanetary disks, based on new and archival observations with the Submillimeter Array. The observed visibility data were modeled with a…

地球与行星天体物理 · 物理学 2017-08-23 Anjali Tripathi , Sean M. Andrews , Tilman Birnstiel , David J. Wilner

Galactic dust emission is polarized at unexpectedly high levels, as revealed by Planck. The origin of the observed $\simeq 20\%$ polarization fractions can be identified by characterizing the properties of optical starlight polarization in…

星系天体物理 · 物理学 2019-04-17 G. V. Panopoulou , B. S. Hensley , R. Skalidis , D. Blinov , K. Tassis

The impact of stellar multiplicity on the evolution of planet-forming disks is still the subject of debate. Here we present and analyze disk structures around ten multiple stellar systems that were included in an unbiased, high spatial…

Observations of far-infrared (FIR) and submillimeter (SMM) polarized emission are used to study magnetic fields and dust grains in dense regions of the interstellar medium (ISM). These observations place constraints on models of molecular…

天体物理学 · 物理学 2009-03-19 John E. Vaillancourt

We propose a set of standard assumptions for the modelling of Class II and III protoplanetary disks, which includes detailed continuum radiative transfer, thermo-chemical modelling of gas and ice, and line radiative transfer from optical to…

We report Very Large Array observations at 7 mm, 9 mm, and 3 cm toward the pre-transitional disk of the Herbig Ae star HD 169142. These observations have allowed us to study the mm emission of this disk with the highest angular resolution…

We present high resolution (R ~ 60,000) circular spectropolarimetry of the classical T Tauri star TW Hydrae. We analyze 12 photospheric absorption lines and measure the net longitudinal magnetic field for 6 consecutive nights. While no net…

天体物理学 · 物理学 2008-11-26 H. Yang , C. M. Johns-Krull , J. A. Valenti

Debris discs are typically revealed through excess emission at infrared wavelengths. Most discs exhibit excess at mid- and far-infrared wavelengths, analogous to the solar system's Asteroid and Edgeworth-Kuiper belts. Recently, stars with…

地球与行星天体物理 · 物理学 2016-07-20 J. P. Marshall , D. V. Cotton , K. Bott , S. Ertel , G. M. Kennedy , M. C. Wyatt , C. del Burgo , O. Absil , J. Bailey , L. Kedziora-Chudczer

This is the second in a series of papers based on data from DISCS, a Submillimeter Array observing program aimed at spatially and spectrally resolving the chemical composition of 12 protoplanetary disks. We present data on six Southern sky…

We present Very Large Array observations at 3.5 cm of the nearby young star TW Hya that show the emission is constant in time over weeks, months and years, and spatially resolved with peak brightness temperature ~10 K at ~0.25 (15 AU)…

天体物理学 · 物理学 2009-11-13 D. J. Wilner , P. D'Alessio , N. Calvet , M. J. Claussen , L. Hartmann

We present the discovery of a spatially unresolved source of sub-millimeter continuum emission ($\lambda=855$ $\mu$m) associated with a young planet, PDS 70 c, recently detected in H$\alpha$ emission around the 5 Myr old T Tauri star PDS…

地球与行星天体物理 · 物理学 2019-07-17 Andrea Isella , Myriam Benisty , Richard Teague , Jaehan Bae , Miriam Keppler , Stefano Facchini , Laura M Pérez

Characterizing the physical properties of dust grains in a protoplanetary disk is critical to comprehending the planet formation process. Our study presents ALMA high-resolution observations of the young protoplanetary disk around DG Tau at…

A sample of large northern Spitzer Infrared Nearby Galaxies Survey (SINGS) galaxies was recently observed with the Westerbork Synthesis Radio Telescope (WSRT) at 1300-1760 MHz. In Paper II of this series, we described sensitive observations…

宇宙学与河外天体物理 · 物理学 2015-05-18 Robert Braun , George Heald , Rainer Beck

The linearly polarized millimeter and sub-millimeter emission in Sagittarius A* is produced within 10 Schwarzschild radii of the supermassive black hole at the Galactic Center and may originate from a hot magnetized accretion disk, where…

天体物理学 · 物理学 2009-11-13 Siming Liu , Lei Qian , Xue-Bing Wu , Christopher L. Fryer , Hui Li

We have investigated molecular distributions in protoplanetary disks, adopting a disk model with a temperature gradient in the vertical direction. The model produces sufficiently high abundances of gaseous CO and HCO+ to account for line…

天体物理学 · 物理学 2009-11-07 Y. Aikawa , G. J. van Zadelhoff , E. F. van Dishoeck , E. Herbst

We model the vertical structure of magnetized accretion disks subject to viscous and resistive heating, and irradiation by the central star. We apply our formalism to the radial structure of magnetized accretion disks threaded by a poloidal…

星系天体物理 · 物理学 2016-01-27 S. Lizano , C. Tapia , Y. Boehler , P. D'Alessio

We present a high angular resolution ($\sim 0.2^{\prime\prime}$), high sensitivity ($\sigma \sim 0.2$ mJy) survey of the 870 $\mu$m continuum emission from the circumstellar material around 49 pre-main sequence stars in the $\rho$ Ophiuchus…