English
Related papers

Related papers: Exploring Brown Dwarf Disks in rho Oph

200 papers

Massive stars play an important role in many areas of astrophysics, but numerous details regarding their formation remain unclear. In this paper we present and analyse high resolution (R ~ 30,000) near-infrared 2.3 micron spectra of 20…

We present Spitzer/IRAC and MIPS 24mu archival observations for 28 brown dwarfs in the Upper Scorpius (UppSco) region. We find a disk fraction of 10.7%^(+8.7%)_(-3.3%). One object shows a small excess at 24mu but none at shorter…

Solar and Stellar Astrophysics · Physics 2014-11-20 B. Riaz , N. Lodieu , J. E. Gizis

Using the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope, we have obtained mid-infrared photometry of the least massive known brown dwarf in the Chamaeleon I star-forming region. For this young brown dwarf, OTS 44, we have…

Bayesian atmospheric retrieval tools can place constraints on the properties of brown dwarfs and hot Jupiters atmospheres. To fully exploit these methods, high signal-to-noise spectral libraries with well-understood uncertainties are…

We present a complete low-resolution (R~100) near-infrared spectrum of the substellar object GY11, member of the rho-Ophiuchi young association. The object is remarkable because of its low estimated mass and age and because it is associated…

Astrophysics · Physics 2009-11-07 L. Testi , A. Natta , E. Oliva , F. D'Antona , F. Comeron , C. Baffa , G. Comoretto , S. Gennari

We present new far-ultraviolet observations of the young M8 brown dwarf 2MASS J12073346-3932539, which is surrounded by an accretion disk. The data were obtained using the Hubble Space Telescope-Cosmic Origins Spectrograph. Moderate…

Solar and Stellar Astrophysics · Physics 2015-05-18 Kevin France , Jeffrey L. Linksy , Alexander Brown , Cynthia S. Froning , Stephane Beland

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

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…

The formation of brown dwarfs (BDs) due to the fragmentation of proto-stellar disks undergoing pairwise encounters was investigated. High resolution allowed the use of realistic initial disk models where both the vertical structure and the…

Solar and Stellar Astrophysics · Physics 2015-05-14 Sijing Shen , James Wadsley , Tristen Hayfield , Nicholas Ellens

We investigate the mass function in the substellar domain down to a few Jupiter masses in the young sigma Orionis open cluster (3+/-2 Ma, d = 360^+70_-60 pc). We have performed a deep IJ-band search, covering an area of 790 arcmin^2 close…

We report the results of deep infrared observations of brown dwarf candidates in the Trapezium cluster in Orion. Analysis of the JHK color-color diagram indicates that a large fraction (approx 65% +/- 15%) of the observed sources exhibit…

Astrophysics · Physics 2009-09-15 August Muench , Joao Alves , Charles Lada , Elizabeth Lada

We present predictions for the surface density of ultracool dwarfs (with spectral types M8-T8) for a host of deep fields that are likely to be observed with the James Webb Space Telescope. Based on simple thin and thick/thin disk…

Astrophysics of Galaxies · Physics 2016-04-06 R. E. Ryan , I. N. Reid

Spitzer Space Observatory IRAC and MIPS photometric observations are presented for 20 white dwarfs with T < 20,000 K and metal-contaminated photospheres. A warm circumstellar disk is detected at GD 16 and likely at PG 1457-086, while the…

Earth and Planetary Astrophysics · Physics 2011-02-11 J. Farihi , M. Jura , B. Zuckerman

We present the results of photometric and spectroscopic follow-ups of the lowest mass member candidates in the nearest OB association, Upper Scorpius (5-10 Myr; 145+/-17 pc), with the Gran Telescopio de Canarias (GTC) and European Southern…

Solar and Stellar Astrophysics · Physics 2017-11-15 N. Lodieu , M. R. Zapatero Osorio , V. J. S. Bejar , K. Pena Ramirez

The masses and temperatures of young low mass stars and brown dwarfs in star- forming regions are not yet well established because of uncertainties in the age of individual objects and the spectral type vs. temperature scale appropriate for…

Astrophysics · Physics 2009-11-13 F. C. Riddick , P. F. Roche , P. W. Lucas

We present an analysis of brown dwarf model spectra in the mid-infrared spectral region (5 - 20 microns), in anticipation of data obtained with the Space Infrared Telescope Facility. The mid-infrared spectra of brown dwarfs are in several…

Astrophysics · Physics 2007-05-23 D. Saumon , M. S. Marley , K. Lodders

We have carried out a Spitzer survey for brown dwarf (BD) disks in the ~5 Myr old Upper Scorpius (UpSco) star forming region, using IRS spectroscopy from 8 to 12\mu m and MIPS photometry at 24\mu m. Our sample consists of 35 confirmed very…

We have combined new I, J, H, and Ks imaging of portions of the Chamaeleon II, Lupus I, and Ophiuchus star-forming clouds with 3.6 to 24 micron imaging from the Spitzer Legacy Program, "From Molecular Clouds to Planet Forming Disks", to…

Astrophysics · Physics 2009-11-11 K. N. Allers , J. E. Kessler-Silacci , L. A. Cieza , D. T. Jaffe

The formation of brown dwarfs via encounters between proto-stars has been confirmed with high-resolution numerical simulations with a restricted treatment of the thermal conditions. The new results indicate that young brown dwarfs (BDs)…

Astrophysics · Physics 2010-11-11 Sijing Shen , James Wadsley

We have obtained multi-fibre intermediate-resolution optical spectroscopy of 94 photometric and proper motion selected low-mass star and brown dwarf candidates in Upper Sco with AAT/AAOmega. We have estimated the spectral types and measured…

Solar and Stellar Astrophysics · Physics 2015-05-20 N. Lodieu , P. D. Dobbie , N. C. Hambly