Results 81 to 90 of about 48,990 (297)

Brown Dwarf Companions to Solar-Type Stars and other Brown Dwarfs [PDF]

Symposium - International Astronomical Union, 2004
We report on our ongoing imaging efforts to detect brown dwarfs orbiting solar-type stars and other brown dwarfs. We study the properties of brown dwarf companions as a function of primary mass. Our results indicate that the frequency of brown dwarf companions around solar-type stars for separations larger than about 40 AU is non-negligible.
Eduardo L. Martín, Mike Connelley, Dan Potter, Hervé Bouy   +3 more
openaire   +1 more source

Do CSR Efforts Reduce Environmental Decoupling: Evidence From S&P 500 Firms

Corporate Social Responsibility and Environmental Management, EarlyView.
ABSTRACT This study investigates the impact of Corporate Social Responsibility (CSR) committees and CSR‐focused employee training on environmental decoupling. Using panel data of 2489 firm‐year observations from S&P 500 firms between 2009 and 2022, we employ fixed‐effects models to examine how CSR governance mechanisms influence the alignment between ...
Burcu Gürol, Yan Wang, Gerçek Özparlak   +2 more
wiley   +1 more source

Reweighting Scheme for the Calculation of Grand‐Canonical Expectation Values in Quantum Monte Carlo Simulations With a Fermion Sign Problem

Contributions to Plasma Physics, EarlyView.
ABSTRACT Ab initio path integral Monte Carlo (PIMC) simulations constitute the gold standard for the estimation of a broad range of equilibrium properties of a host of interacting quantum many‐body systems spanning a broad range of conditions from ultracold atoms to warm dense quantum plasmas.
Paul Hamann, Jan Vorberger, Tobias Dornheim   +2 more
wiley   +1 more source

Simulations of Electron Beam Interactions in Brown Dwarf Atmospheres

The Astrophysical Journal
Over two decades ago, the first detection of electron cyclotron maser instability radio emission from a brown dwarf confirmed the presence of aurorally precipitating electrons on these objects.
Anna Zuckerman, J. Sebastian Pineda, David Brain, James Mang, Caroline V. Morley   +4 more
doaj   +1 more source

Akari Observations of Brown Dwarfs. II CO2 as Probe of Carbon and Oxygen Abundances in Brown Dwarfs

, 2011
Recent observations with the infrared astronomical satellite AKARI have shown that the CO2 bands at 4.2 micron in three brown dwarfs are much stronger than expected from the unified cloudy model (UCM) based on recent solar C & O abundances.
Allende Prieto, Ayres, Burgasser, Burgasser, Burgasser, Cushing, Edvardsson, Grevesse, Griffith, Issei Yamamura, Leggett, Leggett, Leggett, Marley, Noll, Oppenheimer, Satoko Sorahana, Saumon, Stephens, Takashi Tsuji, Tsuji, Tsuji, Tsuji, Vrba, Yamamura   +24 more
core   +1 more source

Environmental and local habitat variables as predictors of trophic interactions in subtidal rocky reefs along the SE Pacific coast

Ecography, EarlyView.
Temperature generally drives latitudinal patterns in the strength of trophic interactions, including consumption rates. However, local community and other environmental conditions might also affect consumption, disrupting latitudinal gradients, which results in complex large‐scale patterns.
Catalina A. Musrri, Alistair G. B. Poore, Oscar Pino, Nicolás Riquelme, Wolfgang B. Stotz, Fadia Tala, Martin Thiel   +6 more
wiley   +1 more source

Vegetation on the move: elevational shifts and greening dynamics across the Himalayan alpine zone

Ecography, EarlyView.
This study investigates alpine ‘vegetation line' (the upper limit of continuous plant community) dynamics in the Himalayan alpine zone (HAZ) over a 24‐year timescale (1999–2022) using maximum NDVI products derived from Landsat series datasets, adjusted for sampling bias using phenological modelling.
Ruolin Leng, Stephan Harrison, Dominic Fawcett, Achyut Tiwari, Mike Harrison, Karen Anderson   +5 more
wiley   +1 more source

Atmospheric Abundances and Bulk Properties of the Binary Brown Dwarf Gliese 229Bab from JWST/MIRI Spectroscopy

The Astrophysical Journal Letters
We present JWST/Mid Infrared Instrument (MIRI) low-resolution spectroscopy (4.75–14 μ m) of the first known substellar companion, Gliese 229Bab, which was recently resolved into a tight binary brown dwarf.
Jerry W. Xuan, Marshall D. Perrin, Dimitri Mawet, Heather A. Knutson, Sagnick Mukherjee, Yapeng Zhang, Kielan K. W. Hoch, Jason J. Wang, Julie Inglis, Nicole L. Wallack, Jean-Baptiste Ruffio   +10 more
doaj   +1 more source

PPV Chapter - The Formation of Brown Dwarfs

, 2006
We review five mechanisms for forming brown dwarfs: (i) turbulent fragmentation of molecular clouds, producing very low-mass prestellar cores by shock compression; (ii) collapse and fragmentation of more massive prestellar cores; (iii) disc fragmentation;
Bate, Matthew R., Nordlund, Aake, Reipurth, Bo, Whitworth, Anthony, Zinnecker, Hans   +4 more
core  

Evolution of Young Brown Dwarf Disks in the Mid-Infrared

, 2004
We have imaged two bona-fide brown dwarfs with TReCS/GEMINI-S and find mid-infrared excess emission that can be explained by optically thick dust disk models.
Allard, Apai, Apai, Bontemps, Bouwman, C. P. Dullemond, Chiang, Chiang, Comeron, D. Apai, Draine, Dubrulle, Dullemond, Gizis, Gomez, Honda, I. Pascucci, Itoh, Jayawardhana, Jayawardhana, Joergens, Klein, Liu, Luhman, M. F. Sterzik, Makarov, Meeus, Meeus, Mohanty, Mohanty, Muench, Muzerolle, N. van der Bliek, Natta, Natta, Neuhäuser, Pascucci, Persi, Pryzgodda, Rucinski, Suttner, Telesco, van Boekel, Webb, Weinberger, Wood   +45 more
core   +1 more source