J/AJ/121/2189 Stars within 8 pc of the Sun (Oppenheimer+, 2001)
A coronagraphic survey for companions of stars within 8 parsecs.
Oppenheimer B.R., Golimowski D.A., Kulkarni S.R., Matthews K., Nakajima T.,
Creech-Eakman M., Durrance S.T.
<Astron. J. 121, 2189 (2001)>
=2001AJ....121.2189O 2001AJ....121.2189O
ADC_Keywords: Stars, nearby ; Stars, double and multiple ;
Parallaxes, trigonometric ; Proper motions
Keywords: binaries: visual - stars: low-mass, brown dwarfs - stars: statistics
Abstract:
We present the technique and results of a survey of stars within 8pc
of the Sun with declinations δ>-35° (J2000.00). The survey,
designed to find without color bias faint companions, consists of
optical coronagraphic images of the 1 field of view centered on each
star and infrared direct images with a 32" field of view. The images
were obtained through the optical Gunn r and z filters and the
infrared J and K filters. The survey achieves sensitivities up to 4
absolute magnitudes fainter than the prototype brown dwarf, Gliese
229B. However, this sensitivity varies with the seeing conditions, the
intrinsic brightness of the star observed, and the angular distance
from the star. As a result, we tabulate sensitivity limits for each
star in the survey. We used the criterion of common proper motion to
distinguish companions and to determine their luminosities. In
addition to the brown dwarf Gl 229B, we have identified six new
stellar companions of the sample stars. Since the survey began,
accurate trigonometric parallax measurements for most of the stars
have become available. As a result, some of the stars we originally
included should no longer be included in the 8pc sample. In addition,
the 8pc sample is incomplete at the faint end of the main sequence,
complicating our calculation of the binary fraction of brown dwarfs.
We assess the sensitivity of the survey to stellar companions and to
brown dwarf companions of different masses and ages.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 101 167 The 8 pc Sample
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See also:
III/198 : Palomar/MSU nearby star spectroscopic survey (Hawley+ 1997)
I/238 : Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
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- 6 F6.2 mas plx Parallax
7 A1 --- m_plx Component designation in a multiple system
9- 10 I2 h RAh Right Ascension (J2000) (1)
12- 13 I2 min RAm Right Ascension (J2000) (1)
15- 19 F5.2 s RAs Right Ascension (J2000) (1)
21 A1 --- DE- Sign of the Declination (J2000) (1)
22- 23 I2 deg DEd Declination (J2000) (1)
25- 26 I2 arcmin DEm Declination (J2000) (1)
28- 31 F4.1 arcsec DEs Declination (J2000) (1)
33- 40 F8.2 mas/yr pmRA ? Proper motion in Right Ascension
42- 49 F8.2 mas/yr pmDE ? Proper motion in Declination
51- 55 F5.2 mag Vmag ? The V band magnitude
57- 65 A9 --- CNS3 The Third Catalog of Nearby Stars name (4)
67- 76 A10 --- BD/CD The Durchmusterung name
Bd (Cat. I/71) or CD (Cat. I/108)
78- 87 A10 --- OName Other name
89 A1 --- l_MajAxis Limit flag on MajAxis
90- 96 F7.2 AU MajAxis ? The semi-major axis (2)
98 A1 --- r_plx Reference code for plx (3)
99 A1 --- r_RAm Reference code for the position (3)
100 A1 --- r_Vmag Reference code for Vmag (3)
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Note (1): Coordinates include the proper motion and precession.
Note (2): Derived from the projected separation if the companion is visibly
detected or the radial velocity orbital solution
Note (3):
G = Reid et al., 1995, Cat. III/198
C = Third Catalog of Nearby Stars, Cat. V/70
H = Hipparcos, Cat. I/239
Y = Yale catalog, Cat. I/238
Note (4): stars without name in the CNS3 have been assigned a number
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History:
From electronic version of the journal
* 31-May-2002: for 8pc 198.00A, BD+43 4306 corrected into BD+43 4305
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 30-Aug-2001