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Related papers: CCD Parallaxes for 309 Late-type Dwarfs and Subdwa…

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Photometric VRI and spectroscopic (6000-9500 A) observations of high proper motion stars discovered during the first phase of the SuperCOSMOS RECONS (SCR) search are used to estimate accurate distances to eight new nearby red dwarfs,…

We present 2817 new southern proper motion systems with 0.40 "/yr > mu > 0.18 "/yr and declination between -47 degrees and 00 degrees. This is a continuation of the SuperCOSMOS-RECONS (SCR) proper motion searches of the southern sky. We use…

Solar and Stellar Astrophysics · Physics 2015-05-27 Mark R. Boyd , Jennifer G. Winters , Todd J. Henry , Wei-Chun Jao , Charlie T. Finch , John P. Subasavage , Nigel C. Hambly

Extrasolar planet searches targeting very low-mass stars and brown dwarfs are hampered by intrinsic or instrumental limitations. Time series of astrometric measurements with precisions better than one milli-arcsecond can yield new evidence…

Solar and Stellar Astrophysics · Physics 2014-05-08 J. Sahlmann , P. F. Lazorenko , D. Segransan , E. L. Martin , M. Mayor , D. Queloz , S. Udry

We report the discovery of 158 previously undetected dwarf galaxies in the Fornax cluster central regions using a deep coadded $u, g$ and $i$-band image obtained with the DECam wide-field camera mounted on the 4-meter Blanco telescope at…

We present a statistical parallax study of nearly 2,000 M subdwarfs with photometry and spectroscopy from the Sloan Digital Sky Survey. Statistical parallax analysis yields the mean absolute magnitudes, mean velocities and velocity…

Solar and Stellar Astrophysics · Physics 2015-06-12 John J. Bochanski , Antonia Savcheva , Andrew A. West , Suzanne L. Hawley

We present 1066 speckle measurements of M dwarf multiples observed over 2021-2024, all taken with HRCam on the Southern Astrophysical Research 4.1 m telescope. Among these, 900 observations resolve companions in 212 pairs, with separations…

Solar and Stellar Astrophysics · Physics 2026-01-28 Eliot Halley Vrijmoet , Andrei Tokovinin , Todd J. Henry , Jennifer G. Winters , Wei-Chun Jao , Elliott Horch

Among stars showing carbon molecular bands (C stars), the main sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 C…

Solar and Stellar Astrophysics · Physics 2015-06-12 Paul J. Green

We present CCD surface photometry of 16 nearby dwarf galaxies, many of which were only recently discovered. Our sample comprises both isolated galaxies and galaxies that are members of nearby galaxy groups. The observations were obtained in…

Astrophysics · Physics 2009-11-07 L. N. Makarova , I. D. Karachentsev , E. K. Grebel , O. Yu. Barsunova

Preliminary trigonometric parallaxes and BVI photometry are presented for two dwarf carbon stars, LP765-18 (= LHS1075) and LP328-57 (= CLS96). The data are combined with the literature values for a third dwarf carbon star, G77-61 (=…

We assembled a catalogue of bright, hot subdwarf and white dwarf stars extracted from a joint ultraviolet, optical, and infrared source list. The selection is secured using colour criteria that correlate well with effective temperatures…

Solar and Stellar Astrophysics · Physics 2015-05-19 S. Vennes , A. Kawka , P. Nemeth

We present an analysis of long-term photometric variability for nearby red dwarfs at optical wavelengths. The sample consists of 264 M dwarfs south of DEC = +30 with V-K = 3.96-9.16 and Mv~10-20 (spectral types M2V-M8V), most of which are…

We measured absolute trigonometric parallaxes and proper motions with respect to many background galaxies for a sample of ten ultracool subdwarfs. The observations were taken in the H-band with the OMEGA2000 camera at the 3.5m-telescope on…

Astrophysics · Physics 2009-11-13 E. Schilbach , S. Roeser , R. -D. Scholz

We report the results of our HST snapshot survey with the ACS HRC PR200L prism, designed to measure the near-UV emission in a sample of nearby M dwarfs. 33 stars were observed, spanning the mass range from 0.1 - 0.6 solar masses (T_eff ~…

Astrophysics · Physics 2009-11-13 Lucianne M. Walkowicz , Christopher M. Johns-Krull , Suzanne L. Hawley

We describe the astrometric reduction of images obtained with the FORS2/VLT camera in the framework of an astrometric planet search around 20 M/L-transition dwarfs. We present the correction of systematic errors, the achieved astrometric…

Solar and Stellar Astrophysics · Physics 2014-05-08 P. F. Lazorenko , J. Sahlmann , D. Segransan , E. L. Martin , M. Mayor , D. Queloz , S. Udry

We present the results of an extensive high-resolution imaging survey of M-dwarf multiplicity using the Lucky Imaging technique. The survey made use of the AstraLux Norte camera at the Calar Alto 2.2m telescope and the AstraLux Sur camera…

We use the multi-epoch K$\rm _S$ band observations, covering a $\sim$5 years baseline to obtain milli and sub-milli arcsec precision astrometry for a sample of eighteen previously known high proper motion sources, including precise…

Solar and Stellar Astrophysics · Physics 2017-03-20 J. C. Beamin , R. A. Mendez , R. L. Smart , R. Jara , R. Kurtev , M. Gromadzki , V. Villanueva , D. Minniti , L. C. Smith , P. W. Lucas

We present a catalog of 424 common proper motion companions to Hipparcos stars with good (>3 sigma) parallaxes, thereby effectively providing new parallaxes for these companions. Compared to stars in the Hipparcos catalog, these stars are…

Astrophysics · Physics 2009-11-10 Andrew Gould , Julio Chaname

Five new objects with proper motions between 1.0 arcsec/yr and 2.6 arcsec/yr have been discovered via a new RECONS search for high proper motion stars utilizing the SuperCOSMOS Sky Survey. The first portion of the search, discussed here, is…

Astrophysics · Physics 2009-11-10 N. C. Hambly , T. J. Henry , J. Subasavage , M. Brown , W. -C. Jao

Between 1997 and 2004 several observing runs were conducted mainly with the CTIO 0.9 m to image ICRF counterparts (mostly QSOs) in order to determine accurate optical positions. Contemporary to these deep CCD images the same fields were…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Norbert Zacharias , Marion I. Zacharias

We present imaging results from a high Galactic latitude survey designed to examine the structure of the Galactic halo. The objective of the survey is to identify candidate halo stars which can be observed spectroscopically to obtain radial…