J/AJ/163/180 RVel and BV photometry of 9 γ Doradus stars (Henry+, 2022)
Nine Bright γDoradus Variables Discovered with Ground-based Photometry
Henry G.W., Fekel F.C., Williamson M.H.
<Astron. J., 163, 180 (2022)>
=2022AJ....163..180H 2022AJ....163..180H
ADC_Keywords: Stars, variable; Stars, early-type; Stars, double and multiple;
Spectra, optical; Photometry, UBV; Radial velocities
Keywords: Gamma Doradus variable stars ; Early-type stars ; Fundamental
parameters of stars ; Stellar oscillations ; Radial velocity ;
Spectroscopic binary stars ; Stellar photometry ; Period
determination
Abstract:
We have used precise photometric and high-dispersion spectroscopic
observations to study nine candidate γ Doradus (γDor)
stars, identified as optically variable comparison stars in our
photometric studies of Sun-like stars. In this paper, we confirm these
nine candidates as new γDor variables. All exhibit sinusoidal
variability with amplitudes between 6 and 65mmag in Johnson B and
periods from 0.28 to 1.13days. All lie in the same region of the H-R
diagram as our previously confirmed γDor stars. Of the nine
systems, one is a single-lined spectroscopic binary (SB1), two are
double-lined spectroscopic binaries (SB2), and the remaining six are
single stars. We present orbits for the three binary systems: HD34415,
HD144839, and HD182735. Their periods are 6400days or 17.5yr
(adopted), 995±7days, and 1052.4±0.2days, respectively. We
compare our photometric periods with those we derive for six of the
nine stars observed with the Transiting Exoplanet Survey Satellite to
strengthen the confirmation of these new γDor variables.
Finally, because the distribution of γDor stars in the H-R
diagram overlaps with the red edge of the δ Scuti (δSct)
instability strip, we use our ground-based photometric results for the
73 γDor stars confirmed with our Automatic Photoelectric
Telescopes over the past two decades to look at the incidence of
hybrid δSct/γDor stars; these are highly valuable targets
for asteroseismology.
Description:
Between 2007 May and 2012 May we acquired high-dispersion spectrograms
of our nine candidates at the Kitt Peak National Observatory (KPNO)
with the coude feed telescope and coude spectrograph. The
observations were obtained with three different CCD detectors.
Initially, we used a Texas Instruments CCD to obtain spectrograms that
were centered at 6430Å, covered a wavelength range of 84Å, and
had a two-pixel resolution of 0.21Å. We obtained additional
spectrograms from 2011 July through 2021 September with the TSU 2m
Automatic Spectroscopic Telescope (AST) and fiber-fed echelle
spectrograph, located at Fairborn Observatory in southeastern Arizona
(Eaton & Williamson 2007). Initially, the detector was a 2048x4096
SITe ST-002A CCD with 15µm pixels. The resulting echelle
spectrograms have 21 orders that span the wavelength range
4920-7100Å and have an average resolution of 0.17Å.
The follow-up photometric observations of the nine γDor
candidates reported in this paper were acquired between 2006 December
1 and 2008 June 30 with the T3 0.40m Automatic Photoelectric Telescope
(APT) located at Fairborn Observatory. This APT has a single-channel
photometer equipped with a temperature-stabilizedEMI 9924B
photomultiplier tube that measures count rates successively through
Johnson B and V filters.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 68 13 Basic properties of the γDor stars
table3.dat 57 50 Radial velocity observations of HD 34415
table5.dat 39 81 Radial velocity observations of HD 144839
table7.dat 59 151 Radial velocity observations of HD 182735
table10.dat 45 2527 Individual photometric observations of 9 new
γDor Stars
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See also:
II/215 : uvby-beta Catalogue (Hauck+ 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/ApJS/99/135 : Rotation and Spectral Peculiarities (Abt+ 1995)
J/A+AS/126/21 : Velocities and duplicity of F-type dwarfs (Nordstroem+ 1997)
J/A+AS/137/451 : Radial velocities. IX. (Grenier+, 1999)
J/MNRAS/331/45 : New periodic variables (Koen+, 2002)
J/AJ/129/2026 : Differential photometry of HD 8801 (Henry+, 2005)
J/AJ/129/2420 : Proper motion derivatives of binaries (Makarov+, 2005)
J/A+A/455/303 : Nainital-Cape Survey. II. Null results (Joshi+, 2006)
J/A+A/464/377 : HIP binaries with radial velocities (Frankowski+, 2007)
J/AJ/133/1421 : BV differential photometry of 11 gammaDor stars (Henry+, 2007)
J/AJ/142/39 : Sample of 114 γ Doradus candidates (Henry+, 2011)
J/AJ/142/185 : Properties of the eclipsing binary stars HY Vir (Lacy+, 2011)
J/AJ/145/111 : Radial velocities of 5 spectroscopic binaries (Fekel+, 2013)
J/A+A/556/A121 : Identification of metal-poor stars with ANN (Giridhar+, 2013)
J/ApJ/855/75 : 24 years monitoring of Sun and Sun-like stars (Radick+, 2018)
J/A+A/623/A72 : Binarity Hipparcos stars from Gaia pm anomaly (Kervella+,2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD Star HD name
8- 13 I6 --- HIP HIP star identifier
15- 17 A3 --- Comp Component
19- 23 F5.2 mag Vmag [7.14/11.2] V-band magnitude (1)
25- 28 F4.2 mag B-V [0.29/0.62] B-V color (1)
30- 36 F7.4 mas plx [8.21/13]? Gaia DR2 parallax
38- 43 F6.4 mas e_plx [0.04/0.2]? Error on plx
45- 48 F4.2 mag VMAG [2.39/3.04]? V-band absolute magnitude (2)
50- 51 A2 --- SpT Spectral class
53- 60 A8 --- Class Luminosity class
62- 64 I3 km/s vsini [3/125]? Rotational velocity
66- 68 A3 --- Bin Signle lined (SB1) or double lined (SB2)
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Note (1): Single star values and combined values of binary components
are from the Tycho-2 catalog converted to the Johnson system. For the
individual binary components see the text.
Note (2): Computed from the V magnitude and the Gaia parallax.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.3 d HJD [46820/59307] Heliocentric Julian date, HJD-2400000
13- 17 F5.3 --- Phase [0.006/0.76] Fractional phase
20- 23 F4.1 km/s RVelA [30.3/39.3] Observed primary radial velocity
26- 29 F4.1 km/s O-CA [-2.2/2.2] Primary velocity residual (1)
32- 34 F3.1 --- WA [0/0.4] Weight of the primary radial velocity
37- 40 F4.1 km/s RVelB [26.6/40.8]? Observed secondary radial velocity
43- 46 F4.1 km/s O-CB [-1.7/1.4]? Secondary velocity residual (1)
49- 51 F3.1 --- WB [1]? Weight of secondary radial velocity
54- 57 A4 --- Source Observatory source (2)
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Note (1): observed-calculated.
Note (2): Sources as follows:
CfA = Center for Astrophysics
KPNO = Kitt Peak National Observatory
FO = Fairborn Observatory
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.3 d HJD [54585/59349] Heliocentric Julian date, HJD-2400000
12- 16 F5.3 --- Phase [0.01/1] Fractional Phase
19- 23 F5.1 km/s RVel [-37.7/-22.1] Observed Radial Velocity
26- 29 F4.1 km/s O-C [-2.8/4.8] Velocity residual, observed-calculated
32- 34 F3.1 --- Weight [0.3/1] Weight of Radial Velocity
36- 39 A4 --- Source Observatory source (1)
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Note (1): Observatories as follows:
KPNO = Kitt Peak National Observatory
FO = Fairborn Observatory
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.3 d HJD [54367/59372] Heliocentric Julian date, HJD-2400000
12- 16 F5.3 --- Phase [0.001/1] Fractional phase
19- 23 F5.1 km/s RVelA [-34.5/-8.3] Observed primary radial velocity
26- 29 F4.1 km/s O-CA [-4.7/6.2] Primary velocity residual (1)
32- 35 F4.2 --- WA [0.06] Weight of primary radial velocity
38- 42 F5.1 km/s RVelB [-35.6/-1.8] Observed secondary radial velocity
45- 48 F4.1 km/s O-CB [-1.2/1.1] Secondary velocity residual (1)
51- 53 F3.1 --- WB [1] Weight of secondary radial velocity
56- 59 A4 --- Source Observatory source (2)
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Note (1): observed-calculated.
Note (2): Sources as follows:
KPNO = Kitt Peak National Observatory
FO = Fairborn Observatory
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HD Star name
8- 17 F10.4 d HJD [54071/54649] Heliocentric Julian Date, HJD-2400000
19- 24 F6.3 mag VarB [-0.49/0.68]? Variable-Comparison differential mag
in B
26- 31 F6.3 mag VarV [-0.46/1.5]? Variable-Comparison differential mag
in V
33- 38 F6.3 mag ChkB [-2.57/-0.11]? Check-Comparison differential mag
in B
40- 45 F6.3 mag ChkV [-2.45/-0.01]? Check-Comparison differential mag
in V
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDs], 03-May-2022