J/MNRAS/429/859     New companions to nearby low-mass stars  (Jodar+, 2013)
New companions to nearby low-mass stars.
    Jodar E., Perez-Garrido A., Diaz-Sanchez A., Villo I., Rebolo R.,
    Perez-Prieto J.A.
   <Mon. Not. R. Astron. Soc., 429, 859-867 (2013)>
   =2013MNRAS.429..859J 2013MNRAS.429..859J    (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Photometry
Keywords: instrumentation: high angular resolution - binaries: general -
          brown dwarfs - stars: low-mass
Abstract:
    We present high-angular-resolution optical I-band imaging of 451
    late K to mid-M nearby stars. These observations have been performed
    with Astralux and FastCam using the lucky imaging technique. We found
    70 companions with separations between 0.1 and 3.5-arcsec, out of
    which 28 are new discoveries. We derive a total binary fraction of
    20.3+6.9-5.2 per cent. Follow-up observations have been carried out
    for 16 of these new binaries and all of them were confirmed as
    physically associated systems. Parallaxes are available for 70 per
    cent of the binary sample, providing reliable estimates of physical
    separations. We have measured separations and position angles as an
    initial stage for a systematic follow-up aimed to determine orbital
    parameters.
Description:
    we present the results of a high-resolution imaging survey of 451 late
    K and M dwarfs selected from the Gliese catalogue (Gliese 1969;
    Gliese & Jahreiss 1979, 1991, Cat. V/70).
    The observations were carried out during 2008 using Astralux at the
    2.2m telescope at the Centro Astronomico Hispano Aleman (CAHA,
    Almeria, Spain) and FastCam at the 1.5m Carlos Sanchez Telescope at
    Teide Observatory (OT, Tenerife, Spain). The observations were done in
    the Sloan Digital Sky Survey (SDSS) i band at CAHA with pixel scales
    of ∼47mas/pix and the Johnson-Cousin I band at OT with ∼43mas/pix.
File Summary:
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 FileName      Lrecl  Records   Explanations
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ReadMe            80        .   This file
table1.dat        13      451   Objects observed in our survey
table2.dat       161       86   Binary systems found with component separations
                                 lower than 3500mas
table3.dat        38       14  *Ultracool dwarf candidates
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Note on table3.dat: All objects in this table were observed in CAHA using
  the SDSS i band.
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See also:
   V/70 : Nearby Stars, Preliminary 3rd Version (Gliese+ 1991)
Byte-by-byte Description of file: table1.dat
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   Bytes Format Units   Label   Explanations
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   1-  9  A9    ---     Name    Gliese name
  10- 11  A2    ---     Comp    [ABC ] Component
      13  A1    ---   n_Name    [*] *: objects that have companions and
                                 described in more detail in Table 2
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Byte-by-byte Description of file: table2.dat
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   Bytes Format Units   Label     Explanations
--------------------------------------------------------------------------------
   1-  9  A9    ---     Name      Gliese name
  10- 11  A2    ---     Comp      [ABC ] Component
  17- 21  A5    ---     SpType    SIMBAD, CDS spectral classification
  25- 34  A10   "date"  Obs.date  Observation date (1)
  36- 39  I4    mas     rho       Aangular separation of components (2)
  41- 45  F5.1  deg     theta     Position angle
  47- 49  F3.1  deg   e_theta     rms uncertainty on theta
  51- 56  F6.2  AU      Sep       ?=- Projected separation
  58- 62  F5.2  AU    e_Sep       ? rms uncertainty on Sep
  65- 69  F5.3  mag     DImag     ?=- Estimated magnitude difference in the SDSS
                                   i band (CAHA observations) or
                                   Johnson-Cousin I (OT observations)
  70-161  A92   ---     Notes     Notes (3)
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Note (1): Observations during 2008 January 10 and 11 were carried out at OT and
  the others at CAHA.
Note (2): its error is estimated to be less than 10 mas.
Note (3): Objects with column Notes blank or with proper motion data are new
  binary systems found in our survey, while objects with a reference in this
  column are known binary systems.
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Byte-by-byte Description of file: table3.dat
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   Bytes Format Units   Label     Explanations
--------------------------------------------------------------------------------
   1-  9  A9    ---     Name      Gliese name
  10- 11  A2    ---     Comp      [ABC ] Component
      12  A1    ---   n_Name      [a] a: new binary discovered in this survey
  14- 17  A4    ---     SpType1   Spectral type of primary
  19- 22  F4.2  Msun    M1        Mass of primary
  24- 27  F4.2  mag     Dimag     Difference in i magnitude
  29- 32  F4.2  Msun    M2        Mass of secondary
  34- 38  A5    ---     SpType2   Spectral type of companion
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History:
    From electronic version of the journal
(End)                                      Patricia Vannier [CDS]    08-Apr-2016