Results 61 to 70 of about 43,562 (319)
The Astrophysical Journal Letters, 2023 We report direct observational evidence for a latitudinal dependence of dust cloud opacity in ultracool dwarfs, indicating that equatorial latitudes are cloudier than polar latitudes.
Genaro Suárez +4 more
doaj +1 more source
Interactions between brown-dwarf binaries and Sun-like stars [PDF]
, 2012 Several mechanisms have been proposed for the formation of brown dwarfs, but there is as yet no consensus as to which -- if any -- are operative in nature. Any theory of brown dwarf formation must explain the observed statistics of brown dwarfs. These statistics are limited by selection effects, but they are becoming increasingly discriminating.
arxiv +1 more source
The Search for Brown Dwarfs around White Dwarfs [PDF]
Symposium - International Astronomical Union, 2003 The infrared search for substellar companions to nearby white dwarfs has been going on for a little more than a decade. The most recent phase has been a wide field proper motion search carried out primarily at Steward Observatory, where we are complete down to J = 18. Earlier phases included near field searches at the IRTF and Keck Observatory.
E. E. Becklin, Jay Farihi, Ben Zuckerman
openaire +3 more sources
Biological Diversity, EarlyView.Abstract The production of Carica papaya L. in Kenya is seriously affected by the Moroccan watermelon mosaic virus and lack of improved varieties leading to the importation of expensive seeds for the resource‐scarce farmers. To curb these challenges, new papaya hybrid lines were recently selected and bred, but their growth traits and performance ...
Janet Chepng’etich Kosgei +4 more
wiley +1 more source
The Astronomical Journal, 2023 Excess infrared flux from white dwarf stars is likely to arise from a dusty debris disk or a cool companion. In this work, we present near-infrared spectroscopic observations with Keck/MOSFIRE, Gemini/GNIRS, and Gemini/Flamingos-2 of seven white dwarfs ...
Dylan Owens +9 more
doaj +1 more source
On the existence of brown dwarfs more massive than the hydrogen burning limit [PDF]
, 2018 Almost by definition brown dwarfs are objects with masses below the hydrogen burning limit, around $0.07\ M_\odot$. Below this mass, objects never reach a steady state where they can fuse hydrogen. Here we demonstrate, in contrast to this traditional view, that brown dwarfs with masses greater than the hydrogen burning limit may in principle exist in ...
arxiv +1 more source
Infrared Searches for Dark Matter in the Form of Brown Dwarfs [PDF]
Mon.Not.Roy.Astron.Soc.266:775,1994, 1993 Brown dwarfs, stars with insufficient mass to burn hydrogen, could contribute to the dark matter in the Galactic disk, galactic halos or even a background critical density. We consider the detectability of such brown dwarfs in various scenarios, extending previous work by allowing for the possibility that they may have an extended mass spectrum or be ...
arxiv +1 more source
Corporate Social Responsibility and Environmental Management, EarlyView.ABSTRACT Studies on the relationship between board diversity and CSR disclosure have shown mixed results. This study investigates the relationship between board diversity attributes and CSR disclosure, as well as the various cultural conditions influencing board diversity–CSR disclosure relationships through meta‐analysis based on data from 45 ...
Waris Ali +2 more
wiley +1 more source
Finding ultracool brown dwarfs with MegaCam on CFHT: method and first results [PDF]
, 2008 We present the first results of a wide field survey for cool brown dwarfs with the MegaCam camera on the CFHT telescope, the Canada-France Brown Dwarf Survey, hereafter CFBDS. Our objectives are to find ultracool brown dwarfs and to constrain the field-brown dwarf mass function thanks to a larger sample of L and T dwarfs. We identify candidates in CFHT/
arxiv +1 more source
The brown dwarf desert as a consequence of orbital migration [PDF]
Mon.Not.Roy.Astron.Soc. 330 (2002) L11, 2001 We show that the dearth of brown dwarfs in short-period orbits around Solar-mass stars - the brown dwarf desert - can be understood as a consequence of inward migration within an evolving protoplanetary disc. Brown dwarf secondaries forming at the same time as the primary star have masses which are comparable to the initial mass of the protoplanetary ...
arxiv +1 more source