J/AJ/133/394 Low-mass binary companions in M35 (McNamara+, 2007)
Searching for low-mass binary companions in M35 using the fine guidance sensors
of the Hubble Space Telescope.
McNamara B.J., Harrison T.E., McArthur B.
<Astron. J., 133, 394-402 (2007)>
=2007AJ....133..394M 2007AJ....133..394M
ADC_Keywords: Associations, stellar ; Stars, double and multiple ;
Photometry, HST
Keywords: astrometry - binaries: general - stars: formation
Abstract:
The Hubble Space Telescope Fine Guidance Sensors data on 23 stars in
the intermediate-age cluster M35 having B-V<0.5 (∼F7V) are
analyzed to test whether binary periods, separations, and masses can
be estimated by measuring periodic variations in the residuals of
their internal proper motions. Of the 23 stars examined, 4 appear to
possess a periodic signal. Unfortunately, these detections cannot be
considered firm because the amplitudes of these waveforms are small
(∼1mas), the signal is only seen in one coordinate, and the derived
periods are close to the duration of the data set. If the signals are
real, they predict binary separations of >6AU, secondary masses
between 0.3 and 0.6M☉, and mass ratios of about 0.2. This latter
value is in agreement with capture models employing stars with
circumstellar disks for the formation of binaries.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 64 93 HST FGS Observations of M35 Stars in the POS Mode
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See also:
J/MNRAS/306/361 : UBVI CCD photometry of M35 (NGC 2168) (Sung+ 1999)
J/ApJ/546/1006 : VRI photometry of M35 (Barrado y Navascues+, 2001)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- FGS FGS number, Cl* NGC 2168 FGS NNN in Simbad
5- 6 I2 h RAh Right ascension (J2000.0)
8- 9 I2 min RAm Right ascension (J2000.0)
11- 15 F5.2 s RAs Right ascension (J2000.0)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 28 F5.2 arcsec DEs Declination (J2000)
30- 32 I3 --- Nm Number of measurements
34- 38 F5.2 mag Vmag V magnitude
40- 43 F4.2 mag B-V ?=- B-V colour index
45- 49 F5.2 yr Time Time spanned by the FGS POS observations
51- 64 A14 --- Com Comment
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Dec-2008