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Related papers: Lucky Imaging of M subdwarfs

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Detailed chemical analyses of M dwarfs are scarce but necessary to constrain the formation environment and internal structure of planets being found around them. We present elemental abundances of 13 M dwarfs (2900 < Teff < 3500 K) observed…

We have identified 109 White Dwarf (WD) - M dwarf pairs in the Sloan Digital Sky Survey (SDSS) with g < 20th magnitude. For each system we determined the temperature of the WD primary and the spectral type of the M dwarf secondary. Using…

The identification and characterisation of low-mass binaries is of importance for a range of astrophysical investigations. Low-mass binaries in young ($\sim10 - 100 $ Myr) moving groups (YMGs) are of particular significance as they provide…

The mass-luminosity relation for late-type stars has long been a critical tool for estimating stellar masses. However, there is growing need for both a higher-precision relation and a better understanding of systematic effects (e.g.,…

We report on 25 sub-arcsecond binaries, detected for the first time by means of lunar occultations in the near-infrared as part of a long-term program using the ISAAC instrument at the ESO Very Large Telescope. The primaries have magnitudes…

Solar and Stellar Astrophysics · Physics 2015-06-16 A. Richichi , O. Fors , F. Cusano , M. Moerchen

Approximately 70 percent of the nearby white dwarfs appear to be single stars, with the remainder being members of binary or multiple star systems. The most numerous and most easily identifiable systems are those in which the main sequence…

Solar and Stellar Astrophysics · Physics 2015-06-16 J. B. Holberg , T. D. Oswalt , E. M. Sion , M. A. Barstow , M. R. Burleigh

We report dynamical mass measurements for the components of the previously known double-lined spectroscopic subdwarfs G 006-026 B and C using the Fine Guidance Sensors (FGS) on the Hubble Space Telescope. To build the empirical…

Solar and Stellar Astrophysics · Physics 2016-11-15 Wei-Chun Jao , Ed Nelan , Todd Henry , Otto Franz , Lawrence Wasserman

We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on IRTF. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of $J \sim 20.5$ and $K \sim 18.5$, corresponding to…

[Abridged] We present maps of CO 2-1 emission covering the entire star-forming disks of 16 nearby dwarf galaxies observed by the IRAM HERACLES survey. The data have 13 arcsec angular resolution, ~250 pc at our average distance of 4 Mpc, and…

We present the spectroscopic analysis of a large sample of late-M, L, and T dwarfs from UKIDSS. Using the YJHK photometry from ULAS and the red-optical photometry from SDSS we selected a sample of 262 brown dwarf candidates and we…

Solar and Stellar Astrophysics · Physics 2015-06-24 F. Marocco , H. R. A. Jones , A. C. Day-Jones , D. J. Pinfield , P. W. Lucas , B. Burningham , Z. H. Zhang , R. L. Smart , J. I. Gomes , L. Smith

The blue supergiant (BSG) domain contains a large variety of stars whose past and future evolutionary paths are still highly uncertain. Since binary interaction plays a crucial role in the fate of massive stars, investigating the…

We report the discovery and characterization of a wide binary population in the ultrafaint dwarf galaxy Bo\"{o}tes I using deep JWST/NIRCam imaging. Our sample consists of 52 candidate binaries with projected separations of 7,000 - 16,000…

Use of the highly sensitive Hokupa'a/Gemini curvature wavefront sensor has allowed direct adaptive optics (AO) guiding on very low mass (VLM) stars with SpT=M8.0-L0.5. A survey of 39 such objects detected 9 VLM binaries. Most of these…

Astrophysics · Physics 2009-11-07 Laird M. Close , Nick Siegler , Melanie Freed , Beth Biller

We analyze five years of PLANET photometry of microlensing events toward the Galactic bulge to search for the short-duration deviations from single lens light curves that are indicative of the presence of planetary companions to the primary…

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 2008-11-26 S. Geier , C. Karl , H. Edelmann , U. Heber , R. Napiwotzki

This work presents the medium-resolution ($R \sim 1,500$) spectroscopic follow-up of 522 low-metallicity star candidates from the Southern Photometric Local Universe Survey (S-PLUS). The objects were selected from narrow-band photometry,…

We present optical (BVRI) photometric measurements of a sample of 76 common proper motion wide separation main sequence binary pairs. The pairs are composed of a F-, G-, or K-type primary star and an M-type secondary. The sample is selected…

Solar and Stellar Astrophysics · Physics 2015-06-22 Ting Li , J. L. Marshall , Sebastien Lepine , Patrick Williams , Joy Chavez

We have completed a high-resolution (R=60,000) optical spectroscopic survey of 185 nearby M dwarfs identified using ROSAT data to select active, young objects with fractional X-ray luminosities comparable to or greater than Pleiades…

Solar and Stellar Astrophysics · Physics 2014-11-18 Evgenya Shkolnik , Michael C. Liu , I. Neill Reid

We present relative positions of visual binaries observed during 2009 with the FastCam "lucky-imaging" camera at the 1.5-m Carlos Sanchez Telescope (TCS) at the Observatorio del Teide. We obtained 424 CCD observations (averaged in 198 mean…

Solar and Stellar Astrophysics · Physics 2015-05-30 F. M. Rica , R. Barrena , G. Vazquez , J. A. Henriquez , F. Hernandez

Searching for compact objects (black holes, neutron stars, or white dwarfs) in the Milky Way is essential for understanding the stellar evolution history, the physics of compact objects, and the structure of our Galaxy. Compact objects in…

Solar and Stellar Astrophysics · Physics 2022-09-29 Hui-Jun Mu , Wei-Min Gu , Tuan Yi , Ling-Lin Zheng , Hao Sou , Zhong-Rui Bai , Hao-Tong Zhang , Ya-Juan Lei , Cheng-Ming Li
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