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Related papers: Brown Dwarf Companions to White Dwarfs

200 papers

Brown dwarfs occupy the important region in the mass range between stars and planets. Their existence, ambigious until only recently, and their properties give insight into stellar and planetary formation. We present statistical results of…

Astrophysics · Physics 2007-05-23 Patrick J. Lowrance

White dwarf main-sequence (WDMS) binaries provide important laboratories for studying binary evolution and the formation of low-mass white dwarfs. In this work, we identify 654 reliable WDMS candidates with FGK-type companions from an…

Ultra-cool dwarfs as wide companions to subgiants, giants, white dwarfs and main sequence stars can be very good benchmark objects, for which we can infer physical properties with minimal reference to theoretical models, through association…

Solar and Stellar Astrophysics · Physics 2010-01-21 Z. H. Zhang , D. J. Pinfield , A. C. Day-Jones , B. Burningham , H. R. A. Jones

Wide binaries made up of two white dwarfs (WDs) receive far less attention than their tight counterparts. However, our tests using the binary population synthesis code {\tt StarTrack} indicate that, for any set of reasonable initial…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeff J. Andrews , Marcel A. Agüeros , Krzysztof Belczynski , Saurav Dhital , S. J. Kleinman , Andrew A. West

Infrared excesses around white dwarf stars indicate the presence of various astrophysical objects of interest, including companions and debris disks. In this second paper of a series, we present follow-up observations of infrared excess…

We present a large-scale, volume-limited companion survey of 245 late-K to mid-M (K7-M6) dwarfs within 15 pc. Infrared adaptive optics (AO) data were analysed from the Very Large Telescope, Subaru Telescope, Canada-France-Hawaii Telescope,…

Solar and Stellar Astrophysics · Physics 2015-06-24 K. Ward-Duong , J. Patience , R. J. De Rosa , J. Bulger , A. Rajan , S. P. Goodwin , Richard J. Parker , D. W. McCarthy , C. Kulesa

We present 11 candidate late-type companions to nearby stars identified with data from the Wide-field Infrared Survey Explorer (WISE) and the Two Micron All-Sky Survey (2MASS). Eight of the candidates are likely to be companions based on…

Cold, low-mass, field brown dwarfs are important for constraining the terminus of the stellar mass function, and also for optimizing atmospheric studies of exoplanets. In 2020 new model grids for such objects were made available:…

We present the results of a high-resolution spectral differential imaging survey of 12 nearby, relatively young field L dwarfs (<1 Gyr) carried out with HST/NICMOS to search for planetary mass companions at small physical separations from…

Solar and Stellar Astrophysics · Physics 2015-05-19 M. B. Stumpf , W. Brandner , V. Joergens , Th. Henning , H. Bouy , R. Köhler , M. Kasper

SDSSJ125733.63+542850.5 (hereafter SDSSJ1257+5428) is a compact white dwarf binary from the Sloan Digital Sky Survey that exhibits high-amplitude radial velocity variations on a period of 4.56 hours. While an initial analysis suggested the…

Solar and Stellar Astrophysics · Physics 2015-05-18 T. R. Marsh , B. T. Gaensicke , D. Steeghs , J. Southworth , D. Koester , V. Harris , L. Merry

We present the results of a Hubble Space Telescope Wide Field Camera 3 imaging survey of 11 of the lowest mass brown dwarfs in the Pleiades known (25-40 Mjup). These objects represent the predecessors to T dwarfs in the field. Using a…

Solar and Stellar Astrophysics · Physics 2015-05-20 E. V. Garcia , Trent J. Dupuy , Katelyn N. Allers , Michael C. Liu , Niall R. Deacon

In wide double white dwarf (DWD) binaries, in which the co-eval WDs evolve independently, the more massive, faster-evolving WD can be used to obtain a main-sequence lifetime for the less-massive WD. By converting this lifetime into an…

Solar and Stellar Astrophysics · Physics 2014-10-27 Jeff J. Andrews , Marcel A. Agüeros , Alexandros Gianninas , Mukremin Kilic , Saurav Dhital , Scott Anderson

The aim of the project is to identify wide common proper motion companions to a sample of spectroscopically confirmed M and L metal-poor dwarfs (also known as subdwarfs) to investigate the impact of metallicity on the binary fraction of…

Solar and Stellar Astrophysics · Physics 2021-06-30 J. González-Payo , M. Cortés-Contreras , N. Lodieu , E. Solano , Z. H. Zhang , M. -C. Gálvez-Ortiz

The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions like massive white dwarfs (M>1.0 M$_\odot$), neutron stars, or stellar-mass black…

Solar and Stellar Astrophysics · Physics 2015-03-25 T. Kupfer , S. Geier , U. Heber , R. H. Østensen , B. N. Barlow , P. F. L. Maxted , C. Heuser , V. Schaffenroth , B. T. Gänsicke

In the course of an imaging survey we have detected a visual companion to the intermediate-mass star HR 6037. In this letter, we present two epoch observations of the binary with NACO/VLT, and near-IR spectroscopy of the secondary with…

The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis of subluminous B (sdB) stars in close binary systems with…

Astrophysics · Physics 2007-05-23 S. Geier , C. Karl , H. Edelmann , U. Heber , R. Napiwotzki

We present the results of an aperture masking interferometry survey for substellar companions around 67 members of the young (~8-200Myr) nearby (~5-86pc) AB Doradus, Beta Pictoris, Hercules-Lyra, TW Hya, and Tucana-Horologium stellar…

We present preliminary results of an imaging survey for companions to low-luminosity dwarfs with spectral types ranging from M7 to L9. A K-band study with the Near Infrared Camera (NIRC) at the Keck telescope discriminates against…

Astrophysics · Physics 2007-05-23 D. W. Koerner , J. Davy Kirkpatrick , I. N. Reid , J. Gizis

We have conducted a search for pulsar companions to 15 low-mass white dwarfs (LMWDs; M < 0.4 M_Sun) at 820 MHz with the NRAO Green Bank Telescope (GBT). These LMWDs were spectroscopically identified in the Sloan Digital Sky Survey (SDSS),…

Solar and Stellar Astrophysics · Physics 2011-02-11 Marcel A. Agueros , Fernando Camilo , Nicole M. Silvestri , S. J. Kleinman , Scott F. Anderson , James W. Liebert