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Related papers: The "Mysterious" Origin of Brown Dwarfs

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Three component models of the IMF are made to consider possible origins for the observed relative variations in the numbers of brown dwarfs, solar-to-intermediate mass stars, and high mass stars. Three distinct physical processes are noted.…

Astrophysics · Physics 2009-11-10 Bruce G. Elmegreen

We use a compilation of disc galaxy rotation curves to assess the role of the luminous component ("baryons") in the rotation curve diversity problem. As in earlier work, we find that rotation curve shape correlates with baryonic surface…

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

Dwarf galaxies (DGs) serve as extremely challenging objects in extragalactic astrophysics. Their origin is expected to be set as the first units in CDM cosmology. Nevertheless they are the galaxy type most sensitive to environmental in…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 Gerhard Hensler

Dwarf spheroidal galaxies are the most dark matter dominated systems in the nearby Universe and their origin is one of the outstanding puzzles of how galaxies form. Dwarf spheroidals are poor in gas and stars, making them unusually faint,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Elena D'Onghia , Gurtina Besla , Thomas J. Cox , Lars Hernquist

One of the most debated subjects in Astronomy since the discovery of exoplanets is how can we distinguish the most massive of such objects from very-low mass stars like Brown Dwarfs (BDs)? We have been looking for evidences of a difference…

Earth and Planetary Astrophysics · Physics 2016-07-28 Lauren Melissa Flor Torres , Roger Coziol , Klauss-Peter Schröeder , César A. Caretta , Dennis Jack

We present some results from a systematic survey for disks around spectroscopically identified young brown dwarfs and very low mass stars. We find that ~75% of our sample show intrinsic IR excesses, indicative of circum(sub)stellar disks.…

Astrophysics · Physics 2007-05-23 Michael C. Liu

Recent studies have shown that starburst dwarf galaxies have steeply rising rotation curves in their inner parts, pointing to a close link between the intense star formation and a centrally concentrated mass distribution (baryons and dark…

The maximum mass of a star that can produce a white dwarf (WD) is an important astrophysical quantity. One of the best approaches to establishing this limit is to search for WDs in young star clusters in which only massive stars have had…

Blue straggler stars (BSSs) are stars observed to be hotter and bluer than other stars with the same luminosity in their environment. As such they appear to be much younger than the rest of the stellar population. Two main channels have…

Solar and Stellar Astrophysics · Physics 2011-02-11 Hagai B. Perets , Daniel C. Fabrycky

Context: We studied numerically the formation of giant planet (GP) and brown dwarf (BD) embryos in gravitationally unstable protostellar disks and compared our findings with directly-imaged, wide-orbit (>= 50 AU) companions known to-date.…

Earth and Planetary Astrophysics · Physics 2015-06-15 Eduard I. Vorobyov

We use near-infrared data obtained with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope to identify objects having the colors of brown dwarfs (BDs) in the field of the massive galactic cluster NGC 3603. These are identified…

Observations of brown dwarfs provide important feedback on theories of atmospheres and inner structure of substellar objects. Brown dwarf binary systems furthermore offer the unique opportunity to determine the mass of individual brown…

Astrophysics · Physics 2007-05-23 Wolfgang Brandner , Herve Bouy , Eduardo L. Martin , Stefan Umbreit

Galaxy counts from bright ultraviolet (UV) and deep optical spectroscopic surveys have revealed an unexpectedly large number of very blue galaxies. The colors and luminosities of these objects indicate that they are dwarf galaxies…

Astrophysics · Physics 2007-05-23 Michel Fioc , Brigitte Rocca-Volmerange

It is well-known that stars with giant planets are on average more metal-rich than stars without giant planets, whereas stars with detected low-mass planets do not need to be metal-rich. With the aim of studying the weak boundary that…

Earth and Planetary Astrophysics · Physics 2014-07-02 D. Mata Sánchez , J. I. González Hernández , G. Israelian , N. C. Santos , J. Sahlmann , S. Udry

We have created an up-to-date catalogue of 214 brown dwarfs (BDs) in binaries with $P < 10^4$ d. This allows us to examine the population statistics of the brown dwarf desert. We searched $\textit{Gaia}$ DR3 NSS results for orbital…

Solar and Stellar Astrophysics · Physics 2023-10-05 Adam T. Stevenson , Carole A. Haswell , John R. Barnes , Joanna K. Barstow

The onset of planet formation in protoplanetary disks is marked by the growth and crystallization of sub-micron-sized dust grains accompanied by dust settling toward the disk mid-plane. Here we present infrared spectra of disks around brown…

Astrophysics · Physics 2007-05-23 D. Apai , I. Pascucci , J. Bouwman , A. Natta , Th. Henning , C. P. Dullemond

Cloud evolution for various metallicities is investigated by three-dimensional nested grid simulations, in which the initial ratio of rotational to gravitational energy of the host cloud \beta_0 (=10^-1 - 10^-6) and cloud metallicity Z (=0…

Astrophysics · Physics 2009-11-13 Masahiro N. Machida

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

The stellar initial mass function (IMF) is a key property of stellar populations. There is growing evidence that the classical star-formation mechanism by the direct cloud fragmentation process has difficulties reproducing the observed…

Astrophysics of Galaxies · Physics 2015-02-19 Ingo Thies , Jan Pflamm-Altenburg , Pavel Kroupa , Michael Marks