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Related papers: Silicate Evolution in Brown Dwarf Disks

200 papers

The 8-14 micron emission spectra of 12 T Tauri stars in the Taurus/Auriga dark clouds and in the TW Hydrae association obtained with the Infrared Spectrograph (IRS; The IRS is a collaborative venture between Cornell University and Ball…

Analysis of all archival 5--14 micron spectra of field ultracool dwarfs from the Infrared Spectrograph on the Spitzer Space Telescope has shown that absorption by silicates in the 8--11 micron region is seen in most L-type (1300 K to 2200…

Solar and Stellar Astrophysics · Physics 2023-06-28 Genaro Suárez , Stanimir Metchev

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

Core-accretion planet formation begins in protoplanetary disks with the growth of small, ISM dust grains into larger particles. The progress of grain growth, which can be quantified using 10 micron silicate spectroscopy, has broad…

Solar and Stellar Astrophysics · Physics 2015-05-28 Andrew J. I. Skemer , Laird M. Close , Thomas P. Greene , Philip M. Hinz , William F. Hoffmann , Jared R. Males

We present high-resolution optical spectra of 15 objects near or below the sub-stellar limit in the Upper Scorpius and $\rho$ Ophiuchus star-forming regions. These spectra, obtained with the HIRES instrument on the Keck I telescope, are…

Astrophysics · Physics 2009-11-07 Ray Jayawardhana , Subhanjoy Mohanty , Gibor Basri

Disks around brown dwarfs (BDs) are excellent laboratories to study the first steps of planet formation in cold and low-mass disk conditions. The radial-drift velocities of dust particles in BD disks are higher than in disks around more…

Earth and Planetary Astrophysics · Physics 2017-09-13 P. Pinilla , L. H. Quiroga-Nuñez , M. Benisty , A. Natta , L. Ricci , Th. Henning , G. van der Plas , T. Birnstiel , L. Testi , K. Ward-Duong

We announce the discovery of SST-Lup3-1, a very low mass star close to the brown dwarf boundary in Lupus III with a circum(sub)stellar disk, discovered by the `Cores to Disks' Spitzer Legacy Program from mid-, near-infrared and optical…

We present the Spitzer IRS spectra for 33 young stars in Tr 37 and NGC 7160. The sample includes the high- and intermediate-mass stars with MIPS 24 microns excess, the only known active accretor in the 12 Myr-old cluster NGC 7160, and 19…

We have investigated the brown dwarf (BD) and stellar disc fractions in the Upper Scorpius OB Association (USco) and compared them with several other young regions. We have compiled the most complete sample of of all spectroscopically…

Solar and Stellar Astrophysics · Physics 2015-06-03 B. Riaz , N. Lodieu , S. Goodwin , D. Stamatellos , M. Thompson

Aims : We want to investigate whether brown dwarfs (BDs) form like stars or are ejected embryos. We study the presence of disks around BDs in the Taurus cloud, and discuss implications for substellar formation models. Methods : We use…

FU Orionis-type stars are young stellar objects showing large outbursts due to highly enhanced accretion from the circumstellar disk onto the protostar. FUor-type outbursts happen in a wide variety of sources from the very embedded ones to…

Solar and Stellar Astrophysics · Physics 2020-06-10 Á. Kóspál , P. Ábrahám , A. Carmona , L. Chen , J. D. Green , R. van Boekel , J. A. White

Young stars are formed within dusty discs. The grains in the disc are originally of the same size as interstellar dust. Models predict that these grains will grow in size through coagulation. Observations of the silicate features at micron…

We present SCUBA-2 850um observations for 7 very low mass stars (VLMS) and brown dwarfs (BDs): 3 in Taurus, 4 in the TWA, and all classical T Tauri (cTT) analogs. We detect 2 of the 3 Taurus disks, but none of the TWA ones. Our 3sigma…

Recent results indicate that the grain size and crystallinity inferred from observations of silicate features may be correlated with spectral type of the central star and/or disk geometry. In this paper, we show that grain size, as probed…

This paper is one in a series presenting results obtained within the Formation and Evolution of Planetary Systems (FEPS) Legacy Science Program on the Spitzer Space Telescope. Here we present a study of dust processing and growth in seven…

We report the results of mid-IR observations with VISIR at the VLT of 10 ultracool dwarfs members of the nearby Upper Scorpius OB association in four filters ranging between 8.59 (PAH1) to 12.8 $\mu$m (Ne II), and one brown dwarf with…

We present mid-infrared photometry of three very young brown dwarfs located in the $\rho$ Ophiuchi star-forming region -- GY5, GY11 and GY310 --obtained with the Subaru 8-meter telescope. All three sources were detected at 8.6 and…

Mineralogical studies of silicate features emitted by dust grains in protoplanetary disks and Solar System bodies can shed light on the progress of planet formation. The significant fraction of crystalline material in comets, chondritic…

Earth and Planetary Astrophysics · Physics 2015-05-27 Isa Oliveira , Johan Olofsson , Klaus M. Pontoppidan , Ewine F. van Dishoeck , Jean-Charles Augereau , Bruno Merin

The study of the properties of disks around young brown dwarfs can provide important clues on the formation of these very low-mass objects and on the possibility of forming planetary systems around them. The presence of warm dusty disks…

Solar and Stellar Astrophysics · Physics 2016-10-05 L. Testi , A. Natta , A. Scholz , M. Tazzari , L. Ricci , I. de Gregorio Monsalvo

We present the largest sample of brown dwarf (BD) protoplanetary disk spectral energy distributions modeled to date. We compile 49 objects with ALMA observations from four star-forming regions: $\rho$ Ophiuchus, Taurus, Lupus, and Upper…

Solar and Stellar Astrophysics · Physics 2021-11-24 Anneliese M. Rilinger , Catherine C. Espaillat