J/AJ/158/189 HD 126516 radial velocity & photometric observations (Fekel+, 2019)
HD 126516: a triple system containing a short-period eclipsing binary.
Fekel F.C., Henry G.W., Sowell J.R.
<Astron. J., 158, 189 (2019)>
=2019AJ....158..189F 2019AJ....158..189F (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Stars, variable ; Radial velocities ;
Photometry, UBV
Keywords: eclipsing binary stars - spectroscopic binary stars -
fundamental parameters of stars
Abstract:
From numerous radial velocities as well as Johnson B and V differential
photoelectric photometry, we have determined the orbital elements and
other properties of the single-lined triple system HD 126516. This system
consists of a narrow-lined F5 V star and an unseen M dwarf companion
in a 2.1241 day circular orbit. The small, low-mass secondary produces
detectable eclipses of the primary, and that pair has been given the
variable star name V349 Vir. Variations of the center-of-mass velocity
of this short-period system have an orbital period of 702.7 days or 1.92 yr
and an eccentricity of 0.36. The third star is likely a K or M dwarf. From
an analysis of our photometry, we conclude that the primary of HD 126516
is not a γ Dor variable. Comparison with evolutionary tracks
indicates that the primary is slightly metal-poor and has an age of
2.5 Gyr. The projected rotational velocity of the primary is very low,
just 4 km/s, which is 10 times less than its synchronous rotational
velocity. Thus, either that component's rotation is extremely
non-synchronous or the inclinations of the rotational and orbital axes
are very different, and so the primary has a very large spin-orbit
misalignment. Because of the moderate age of the system and the fact that
its orbit is already circularized, neither situation is expected
theoretically.
Description:
The observations of HD 126516 at the Kitt Peak National Observatory (KPNO)
began in 2000 July and continued through 2011 June. During that time,
48 spectra were acquired with the coude feed telescope, coude spectrograph,
and two different detectors. From 2000 through 2010 a Texas Instruments (TI)
CCD was used and centered the spectra in the red at 6430 Å. After the TI
CCD was retired, spectra were obtained in 2011 with a CCD made by
Semiconductor Technology Associates, designated STA2. That CCD consists of
a 2600x4000 array of 12 µm pixels producing a wavelength range of
336 Å for spectra centered at 6430 Å. An additional 186 useful
observations of HD 126516 were obtained at the Fairborn Observatory in
southeastern Arizona from 2004 December through 2018 January with the
Tennessee State University 2 m Automatic Spectroscopic Telescope (AST),
fiber-fed echelle spectrograph, and a CCD detector (Eaton & Williamson
2004SPIE.5496..710E 2004SPIE.5496..710E). From 2004 through 2011 a 2048x4096 SITe ST-002A CCD
with 15 µm pixels was used. The photometric observations of HD 126516
were acquired on 236 nights during its 2002-2003 and 2006-2007 observing
seasons with the Tennessee State University T3 0.4 m Automatic
Photoelectric Telescope (APT) at Fairborn. The precision photometer of
T3 uses an EMI 9924B photomultiplier tube (PMT) that measures photon
count rates successively through Johnson B and V filters.
Objects:
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RA (ICRS) DE Designation(s) (Period)
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14 26 03.09 -00 41 30.3 HD 126516 = V* V349 Vir (P=2.1241)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 52 234 Radial velocity observations of HD 126516
table4.dat 31 723 Photometric observations of HD 126516
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See also:
J/other/IBVS/5863 : 79th Name-List of Variable Stars (Kazarovets+, 2008)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 F9.3 d HJD [51738.711/58141.911] Heliocentric Julian Date,
HJD-2400000
11- 15 F5.1 km/s RV [-63.5/14.6] Observed radial velocity
17- 21 F5.2 km/s O-C [-0.86/0.69] Velocity residual
23- 27 F5.3 --- Phase-L [0.003/0.997] Fractional phase of long period
orbit
29- 34 F6.2 km/s RV-L [-30.49/-19.14] Radial velocity of long period
orbit
36- 40 F5.3 --- Phase-S [0.003/0.992] Fractional phase of short period
orbit
42- 47 F6.2 km/s RV-S [-34.43/34.31] Radial velocity of short period
orbit
49- 52 A4 --- Source Observatory source (1)
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Note (1): Observatory source as follows:
KPNO = The coude feed telescope and coude spectrograph at Kitt Peak National
Observatory;
Fair = The Tennessee State University 2m Automatic Spectroscopic Telescope
and fiber-fed echelle spectrograph at Fairborn Observatory.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d HJD [52635.0308/54282.7076] Reduced Heliocentric Julian
Date, HJD-2400000
12- 17 F6.4 --- Phase [0.0002/0.9996] Fractional orbital phase (1)
19- 24 F6.3 mag VarV [1.86/1.929]?=99.999 Variable-Comparison
differential mag in V (2)
26- 31 F6.3 mag VarB [1.821/1.883]?=99.999 Variable-Comparison
differential mag in B (2)
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Note (1): The fractional phases are based on parameter values listed in Table 7.
Note (2): No value signifies that the differential magnitude was discarded
because its internal standard deviation exceeded 0.01 mag.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 10-Jan-2020