scholarly journals Spectral Energy Distribution and Bolometric Luminosity of the Cool Brown Dwarf Gliese 229B

1996 ◽  
Vol 112 ◽  
pp. 1678 ◽  
Author(s):  
K. Matthews ◽  
T. Nakajima ◽  
S. R. Kulkarni ◽  
B. R. Oppenheimer
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
Brown Dwarf ◽  
Bolometric Luminosity

scholarly journals An 80 au cavity in the disk around HD 34282

2017 ◽  
Vol 607 ◽  
pp. A55 ◽  
Author(s):  
G. van der Plas ◽  
F. Ménard ◽  
H. Canovas ◽  
H. Avenhaus ◽  
S. Casassus ◽  
...  
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Dust Emission ◽  
Radial Distance ◽  
Position Angle ◽  
Spectral Energy ◽  
Brown Dwarf ◽  
Radial Extent ◽  
Disk Evolution ◽  
Co Emission

Context. Large cavities in disks are important testing grounds for the mechanisms proposed to drive disk evolution and dispersion, such as dynamical clearing by planets and photoevaporation. Aims. We aim to resolve the large cavity in the disk around HD 34282, whose presence has been predicted by previous studies modeling the spectral energy distribution of the disk. Methods. Using ALMA band 7 observations we studied HD 34282 with a spatial resolution of 0.10″ × 0.17′′ at 345 GHz. Results. We resolve the disk around HD 34282 into a ring between 0.24′′ and 1.15′′ (78+7-11 and 374+33-54 au adopting a distance of 325+29-47 pc). The emission in this ring shows azimuthal asymmetry centered at a radial distance of 0.46′′ and a position angle of 135° and an azimuthal FWHM of 51°. We detect CO emission both inside the disk cavity and as far out as 2.7 times the radial extent of the dust emission. Conclusions. Both the large disk cavity and the azimuthal structure in the disk around HD 34282 can be explained by the presence of a 50 Mjup brown dwarf companion at a separation of ≈0.1′′.

scholarly journals Imaging of 2-mm dust continuum emission towards S106 FIR and its spectral energy distribution

2002 ◽  
Vol 206 ◽  
pp. 22-25
Author(s):  
Ray S. Furuya ◽  
Yoshimi Kitamura ◽  
Alwyn Wootten ◽  
Mark J. Claussen ◽  
Ryohei Kawabe
Keyword(s):  
Star Formation ◽  
Energy Distribution ◽  
Early Phase ◽  
Spectral Energy Distribution ◽  
Continuum Emission ◽  
Spectral Energy ◽  
Bolometric Luminosity ◽  
The Core ◽  
Dust Temperature

The class 0 source S106 FIR is a good candidate to investigate a very early phase of star formation because of the presence of an AU-scale Microjet, discovered by our VLBA H2O maser observations and the absence of an extensive CO outflow. In order to reveal the properties of S106 FIR, we conducted observations of 2-mm continuum emission with the Nobeyama Millmeter Array. We detected a weak compact continuum emission around S106 FIR. We analysed the spectral energy distribution of S106 FIR. It is found that the dust temperature and the β index of the dust opacity range from 31 to 55 K and from 1.4 to 1.6, respectively. Using these results, we computed the mass of the core aound S106 FIR and the bolometric luminosity of 3.1 to 5.8 M⊙ and 230 to 1070 L⊙, respectively.

scholarly journals Spectral energy distribution simulations of a possible ring structure around the young, red brown dwarf G 196-3 B

2016 ◽  
Vol 464 (1) ◽  
pp. 1108-1118 ◽  
Author(s):  
Olga V. Zakhozhay ◽  
María Rosa Zapatero Osorio ◽  
Víctor J. S. Béjar ◽  
Yann Boehler
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Ring Structure ◽  
Spectral Energy ◽  
Brown Dwarf

scholarly journals On the Possibility to Identify a Companion in a Protoplanetary Disk

2015 ◽  
Vol 10 (S314) ◽  
pp. 211-212
Author(s):  
O. V. Zakhozhay
Keyword(s):  
Energy Distribution ◽  
Profile Analysis ◽  
Spectral Energy Distribution ◽  
Protoplanetary Disks ◽  
Protoplanetary Disk ◽  
Spectral Energy ◽  
The Sun ◽  
Maximum Difference ◽  
Brown Dwarf ◽  
Energy Distributions

AbstractIn this paper, I investigate a possibility to detect a brown dwarf companion in a protoplanetary disk based on spectral energy distribution (SED) profile analysis. I present synthetic spectral energy distributions of protoplanetary disks with and without an embedded companion that clears a gap. The computations are performed for a star (0.8 M⊙) and a substellar companion (30 MJ) at an age of 5 Myr embedded in a protoplanetary disk, located at a distance 100 pc from the Sun. Analysis of the SED profile shape indicates that the maximum difference between the fluxes of the systems with and without the companion is ≈ 0.43 Jy at 34 μm.

scholarly journals A Multi-wavelength MOCASSIN model of the Magellanic-type galaxy NGC 4449

2011 ◽  
Vol 7 (S284) ◽  
pp. 159-162
Author(s):  
O. Ł. Karczewski ◽  
M. J. Barlow ◽  
M. J. Page ◽  
S. C. Madden
Keyword(s):  
Radiative Transfer ◽  
Energy Distribution ◽  
Emission Line ◽  
Spectral Energy Distribution ◽  
Optical Emission ◽  
Spectral Energy ◽  
Irregular Galaxy ◽  
Bolometric Luminosity ◽  
Stellar Component ◽  
Multi Wavelength

AbstractWe use the photoionisation and dust radiative transfer code MOCASSIN to create a model of the dwarf irregular galaxy NGC 4449. The best-matching model reproduces the global optical emission line fluxes and the observed spectral energy distribution (SED) spanning wavelengths from the UV to sub-mm, and requires the bolometric luminosity of 6.25 × 109L⊙ for the underlying stellar component, Mdust/Mgas of 1/680 and Mdust of 2.2 × 106M⊙.

scholarly journals The Influence of Forming Companions on the Spectral Energy Distributions of Stars with Circumstellar Discs

2017 ◽  
Vol 34 ◽  
Author(s):  
Olga V. Zakhozhay
Keyword(s):  
Energy Distribution ◽  
Radiative Transfer Equation ◽  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
Brown Dwarf ◽  
Spectral Energy Distributions ◽  
Distribution Profile ◽  
Energy Distributions ◽  
One Dimensional ◽  
The One

AbstractWe study a possibility to detect signatures of brown dwarf companions in a circumstellar disc based on spectral energy distributions. We present the results of spectral energy distribution simulations for a system with a 0.8 M⊙ central object and a companion with a mass of 30 MJ embedded in a typical protoplanetary disc. We use a solution to the one-dimensional radiative transfer equation to calculate the protoplanetary disc flux density and assume, that the companion moves along a circular orbit and clears a gap. The width of the gap is assumed to be the diameter of the brown dwarf Hill sphere. Our modelling shows that the presence of such a gap can initiate an additional minimum in the spectral energy distribution profile of a protoplanetary disc at λ = 10–100 μm. We found that it is possible to detect signatures of the companion when it is located within 10 AU, even when it is as small as 3 MJ. The spectral energy distribution of a protostellar disc with a massive fragment (of relatively cold temperature ~400 K) might have a similar double peaked profile to the spectral energy distribution of a more evolved disc that contains a gap.

scholarly journals Influence of Microlensing on Spectral Anomalies of the Lensed Objects

2011 ◽  
Vol 20 (3) ◽  
Author(s):  
S. Simić ◽  
L. Č. Popović ◽  
P. Jovanović
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Angular Size ◽  
Black Body ◽  
Spectral Energy

AbstractHere we consider the influence of microlensing on the spectrum of a lensed object with the angular size 5 μas accepting that the composite emission of this object originates from three different regions arranged around its center. We assume that the lensed object has three concentric regions with a black-body emission; the temperatures of these regions are 10 000 K, 7500 K and 5000 K. We investigate how the integral spectral energy distribution (SED) of such stratified source changes due to microlensing by a group of solarmass stars. We find that the SED and flux ratios in the photometric B, V and R passbands show considerable changes during a microlens event. This indicates that the flux anomaly observed in some lensed quasars may be caused by microlensing of a stratified object.

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