J/A+AS/126/21 Velocities and duplicity of F-type dwarfs (Nordstroem+ 1997)
Radial velocities, rotations, and duplicity of a sample of early F-type dwarfs
Nordstroem B., Stefanik R.P., Latham D.W., Andersen J.
<Astron. Astrophys. Suppl. Ser. 126, 21 (1997)>
=1997A&AS..126...21N 1997A&AS..126...21N (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Rotational velocities ; Radial velocities
Keywords: methods: statistical - techniques: radial velocities -
stars: binaries: spectroscopic - stars: kinematics -
Galaxy: solar neighbourhood
Abstract:
We present new radial and rotational velocities for 595 nearby early F
dwarfs, based on digital spectra cross-correlated with individually
optimised synthetic template spectra. The selection of optimum
templates, the determination of rotational velocities, and the
extraction of velocities from the blended spectra of
double-lined spectroscopic binaries are discussed in some detail. We
find 170 spectroscopic binaries in the sample and determine orbits for
18 double-lined and 2 single-lined binaries, including some
spectroscopic triples. 73 stars are listed with too rapid rotation to
yield useful radial velocities (i.e. vsini>120km/s). We discuss the
binary frequency in the sample, and the influence of unrecognised
binaries on the definition of clean metallicity groups of young F
dwarfs and the determination of their kinematical properties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 112 530 Mean radial velocities, mean errors, and
variability indicators for 530 stars with
single-lined spectra
table2 88 65 Mean radial velocities, luminosity ratios, and
other derived parameters for 65 stars with
double-lined or composite spectra
table4 8 73 List of stars which rotate too rapidly for
usable radial-velocity measurements with the
CfA instruments
table5 101 2130 Individual radial-velocity observations for
the single-lined stars
table6 99 746 Individual radial-velocity observations for
the double-lined stars
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Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number of single-lined star
7- 8 A2 --- m_HD Visual binary component code
10- 11 I2 h RAh Right ascension (J2000)
13- 14 I2 min RAm Right ascension (J2000)
16- 19 F4.1 s RAs Right ascension (J2000)
21 A1 --- DE- Declination sign
22- 23 I2 deg DEd Declination (J2000)
25- 26 I2 arcmin DEm Declination (J2000)
28- 29 I2 arcsec DEs Declination (J2000)
31- 34 I4 K Teff Effective temperature (Template spectrum
parameter)
36- 37 I2 [mm/s2] logg Surface gravity (Template spectrum parameter)
39- 43 F5.1 km/s Vrot Estimated rotational velocity, v sin i
46- 47 I2 --- Nobs Number of observations
49- 52 I4 d Span Time span from first to last observation
54- 59 F6.2 km/s Mean radial velocity
61- 65 F5.2 km/s e_ Mean error of mean radial velocity
67- 71 F5.2 km/s sigExt Standard deviation (external error) of the
individual radial velocity observations
73- 76 F4.2 km/s sigInt Expected average (internal) error of a single
radial velocity as computed by XCSAO
78- 82 F5.2 --- sigExt/sigInt Ratio of external to internal errors
84- 91 F8.2 --- chi2 Chi-square of the data set for this star
93-100 F8.6 % P(chi2) Probability that chi^2 is due to observational
errors of a true constant-velocity object
102-106 F5.2 --- Average goodness-of-fit parameter R, from XCSAO
108-112 F5.3 --- Average correlation height, from XCSAO
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number of double-lined star
7 A1 --- m_HD Visual binary component code
9- 10 I2 h RAh Right ascension (J2000)
12- 13 I2 min RAm Right ascension (J2000)
15- 18 F4.1 s RAs Right ascension (J2000)
20 A1 --- DE- Declination sign
21- 22 I2 deg DEd Declination (J2000)
24- 25 I2 arcmin DEm Declination (J2000)
27- 28 I2 arcsec DEs Declination (J2000)
30- 33 I4 K Teff1 ? Synthetic template spectrum effective
temperature, for component 1 in spectrum
35- 37 I3 km/s Vrot1 ? Synthetic template spectrum rotational
velocity, for component 1 in spectrum
39- 42 I4 K Teff2 Synthetic template spectrum effective
temperature, for component 2 in spectrum
44- 46 I3 km/s Vrot2 Synthetic template spectrum rotational
velocity, for component 2 in spectrum
48- 51 F4.2 --- Alpha ? Luminosity ratio (comp2/comp1) computed with
TODCOR (see text)
53- 54 I2 --- Nobs Number of observations
56- 61 F6.2 km/s Mean (systemic) radial velocity, V0
63- 66 F4.2 km/s e_ Mean error of mean radial velocity
68- 71 I4 d Span Time span from first to last observation
73- 77 F5.3 --- q ? Mass ratio q (comp2/comp1) when available;
see paper for methods of computation
79- 83 F5.3 --- e_q ? Mean error of mass ratio
85- 88 A4 --- Rem Remark on nature of system (1)
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Note (1): SB2/3 indicates no. of components detected;
O: preliminary single- or double-lined orbit computed
(see Table 3 and Figure 2);
W: V0 and q computed by Wilson's (1941ApJ....93...29W 1941ApJ....93...29W) method;
C: velocities constant during period of observation
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Byte-by-byte Description of file: table4
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number, for fast-rotating stars not
measurable with the current CfA instruments
7- 8 A2 --- m_HD Visual binary component code
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Byte-by-byte Description of file: table5
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number, as in table1
7- 9 A3 --- m_HD Visual binary component code
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min RAm Right ascension (J2000)
17- 20 F4.1 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 30 I2 arcsec DEs Declination (J2000)
32 A1 --- Tel [WTM] Observatory code (1)
34- 38 I5 --- Obs Serial number of observation
40- 47 A8 --- Star Associated star identification to serial
number of observation
50- 51 I2 [Sun] log[Fe/H] Metal abundance (always solar = 00 here)
53- 56 I4 K Teff Effective temperature (Template spectrum
parameter)
58- 59 I2 [mm/s2] logg Surface gravity (Template spectrum parameter)
61- 63 I3 km/s Vrot Value of vsini selected for the star (Template
spectrum parameter)
65- 77 F13.5 d HJD Heliocentric Julian Date of observation
79- 84 F6.2 km/s RV Radial velocity
86- 90 F5.2 km/s e_RV Mean error of radial velocity as computed
by XCSAO
92- 96 F5.2 ---- R Goodness-of-fit parameter R, from XCSAO
98-101 F4.2 --- height Correlation peak height, from XCSAO
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Note (1): "W": 1.5m Wyeth; "T": 1.5m Tillinghast; "M": MMT 4.2m telescope
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Byte-by-byte Description of file: table6
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number, as in table2
7 A1 --- m_HD Visual binary component code
9- 10 I2 h RAh Right ascension (J2000)
12- 13 I2 min RAm Right ascension (J2000)
15- 18 F4.1 s RAs Right ascension (J2000)
20 A1 --- DE- Declination sign
21- 22 I2 deg DEd Declination (J2000)
24- 25 I2 arcmin DEm Declination (J2000)
27- 28 I2 arcsec DEs Declination (J2000)
30- 33 I4 K Teff1 Synthetic template spectrum effective
temperature for component 1 in spectrum
35- 37 I3 km/s Vrot1 Synthetic template spectrum rotational velocity
for component 1 in spectrum
39- 42 I4 K Teff2 Synthetic template spectrum effective
temperature for component 2 in spectrum
44- 46 I3 km/s Vrot2 Synthetic template spectrum rotational velocity
for component 1 in spectrum
48- 51 F4.2 --- Alpha ? Continuum ratio alpha (comp2/comp1) specified
to TODCOR when fixed for all observations
52 A1 --- n_Alpha [f] f if continuum ratio alpha (comp2/comp1) was
determined by TODCOR for each observation
54- 65 F12.4 d HJD Heliocentric Julian Date of observation
67- 73 F7.2 km/s RV1 Radial velocity of component 1
75- 81 F7.2 km/s RV2 Radial velocity of component 2
83- 87 F5.3 --- L2/L1 Luminosity ratio (comp2/comp1), see above
89- 93 F5.3 --- height Correlation peak height, from TODCOR
95- 97 I3 --- Obs Running number of observation
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Acknowledgements: Johannes Andersen
References:
Nordstrom B. et al., 1994A&A...287..338N 1994A&A...287..338N
Zucker S., Mazeh T., 1994ApJ...420..806Z 1994ApJ...420..806Z
(End) Patricia Bauer [CDS] 13-Jun-1997