J/AJ/162/184 APOGEE: Properties & radial velocities of binaries (Kounkel+, 2021)
Double-lined spectroscopic binaries in the APOGEE DR16 and DR17 data.
Kounkel M., Covey K.R., Stassun K.G., Price-Whelan A.M., Holtzman J.,
Chojnowski D., Longa-Pena P., Roman-Zuniga C.G., Hernandez J., Serna J.,
Badenes C., De Lee N., Majewski S., Stringfellow G.S., Kratter K.M.,
Moe M., Frinchaboy P.M., Beaton R.L., Fernandez-Trincado J.G.,
Mahadevan S., Minniti D., Beers T.C., Schneider D.P., Barba R.,
Brownstein J.R., Garcia-Hernandez D.A., Pan K., Bizyaev D.
<Astron. J., 162, 184 (2021)>
=2021AJ....162..184K 2021AJ....162..184K
ADC_Keywords: Stars, double and multiple; Spectroscopy; Radial velocities;
Infrared; Binaries, eclipsing; Binaries, orbits
Keywords: Spectroscopic binary stars ; Binary stars ; Eclipsing binary stars ;
Near infrared astronomy ; Spectroscopy ; Orbit determination
Abstract:
APOGEE spectra offer ≤1km/s precision in the measurement of stellar
radial velocities. This holds even when multiple stars are captured in
the same spectrum, as happens most commonly with double-lined
spectroscopic binaries (SB2s), although random line-of-sight
alignments of unrelated stars can also occur. We develop a code that
autonomously identifies SB2s and higher order multiples in the APOGEE
spectra, resulting in 7273 candidate SB2s, 813 SB3s, and 19 SB4s. We
estimate the mass ratios of binaries, and for a subset of these
systems with a sufficient number of measurements we perform a complete
orbital fit, confirming that most systems with periods of <10days have
circularized. Overall, we find an SB2 fraction (FSB2) ∼3% among
main-sequence dwarfs, and that there is not a significant trend in
FSB2 with temperature of a star. We are also able to recover a higher
FSB2 in sources with lower metallicity, however there are some
observational biases. We also examine light curves from TESS to
determine which of these spectroscopic binaries are also eclipsing.
Such systems, particularly those that are also pre- and post-main
sequence, are good candidates for a follow-up analysis to determine
their masses and temperatures.
Description:
Apache Point Observatory Galactic Evolution Experiment (APOGEE) is
conducted with two high-resolution spectrographs: one commissioned
first on the 2.5m Sloan Foundation telescope at the Apache Point
Observatory (APO) in New Mexico, United States, and the second
spectrograph (APOGEE-S) subsequently installed on the Irenee du Pont
2.5m telescope at Las Campanas Observatory (LCO) in Chile's Atacama
Region. Both spectrographs can observe up to 300 objects
simultaneously, across 3° and 2° (in diameter) fields of view
at APO and LCO, respectively. The spectrographs cover the spectral
range of 1.51-1.7um with an average resolution of R∼22,500.
The latest public data release is DR16 (Ahumada+2020, V/154;
Jonsson+2020, III/284), covering observations through June of 2018. In
this work, we analyze spectra from a proprietary data product
including APOGEE observations taken through March of 2020, when both
LCO and APO paused observations due to COVID-19.
SDSS-IV APOGEE data (DR17; Abdurro'uf+2022, III/286) were obtained
after APO and LCO re-opened. The DR17 pipeline updated the procedures
used to construct CCFs for each APOGEE spectrum, introducing slight
differences between the DR16 and DR17 reductions that could not be
reconciled in an autonomous manner. Thus, we treat these two data
reductions separately.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 591 8105 Properties of the identified SB2s and higher order
multiples
table3.dat 229 32642 Vetted radial velocities of the individual
components
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See also:
B/sb9 : SB9: 9th Catalogue of Spectroscopic Binary Orbits (Pourbaix+ 2004-2014)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
III/286 : APOGEE-2 DR17 final allStar catalog (Abdurro'uf+, 2022)
V/122 : SB9: 9th Catalogue of Spectroscopic Binary Orbits (Pourbaix+ 2005)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/A+A/433/185 : Detailed abundance analysis of 102 F & G dwarfs (Bensby+, 2005)
J/MNRAS/367/1329 : Elemental abundances for 176 stars (Reddy+, 2006)
J/AJ/140/184 : RAVE double-lined spectroscopic binaries (Matijevic+, 2010)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/AJ/151/144 : ASPCAP weights for the 15 APOGEE chem. elements (Garcia+, 2016)
J/ApJ/829/34 : Kepler heartbeat star radial velocities (Shporer+, 2016)
J/A+A/608/A95 : GES: multi-line spectroscopic binary candidates (Merle+, 2017)
J/MNRAS/478/4513 : GALAH Survey DR2 (Buder+, 2018)
J/ApJ/855/68 : Massive stars: SDSS-IV/APOGEE SURVEY. I. (Roman-Lopes+, 2018)
J/ApJ/873/66 : Massive stars: SDSS/APOGEE-2. II. W3-W4-W5 (Roman-Lopes+, 2019)
J/AJ/156/18 : APOGEE DR14:Bin. companions of evolved stars (Price-Whelan+,2018)
J/AJ/156/45 : M-dwarf multiples in the SDSS-III/APOGEE (Skinner+, 2018)
J/AJ/158/155 : SB candidates from the RAVE & Gaia DR2 surveys (Birko+, 2019)
J/A+A/623/A72 : Binarity of Hipparcos stars: Gaia pm anomaly (Kervella+,2019)
J/AJ/157/196 : Close companions around young stars (Kounkel+, 2019)
J/A+A/635/A155 : Gaia-ESO Survey SB1 catalogue (Merle+, 2020)
J/AJ/159/182 : APOGEE Net, YSOs param. through deep learning (Olney+, 2020)
J/ApJS/249/22 : Radial velocity variable stars from LAMOST DR4 (Tian+, 2020)
J/A+A/638/A145 : GALAH survey. FGK binary stars (Traven+, 2020)
J/other/RAA/23.K5026 : APOGEE DR17 standard stars radial velocities (Li+, 2023)
Byte-by-byte Description of file:table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- ID APOGEE identifier
20- 41 E22.17 deg RAdeg Right ascension in decimal degrees (J2000)
43- 65 E23.17 deg DEdeg Declination in decimal degrees (J2000)
67 I1 --- SBn [2/4] Number of deconvolved components for a
source
69- 70 I2 --- Nepoch [1/47] Epoch number
72- 94 E23.17 --- qW [-300/80]? Mass ratio from a Wilson plot
96- 117 E22.17 --- e_qW [1e-3/66000]? qW uncertainty
119- 141 E23.17 km/s VelW [-3748/291]? Barycenter velocity from a Wilson
plot
143- 164 E22.17 km/s e_VelW [1e-3/2200]? VelW uncertainty
166- 176 E11.6 d Per [0.8/348]? Period
178- 188 E11.6 d e_Per [3.2e-7/52]? Per uncertainty
190- 200 E11.6 d T0 [2.455e+6/2.459e+6]? Time of periastron
passage
202- 212 E11.6 d e_T0 [8.9e-5/52]? T0 uncertainty
214- 224 E11.6 --- e [1.08e-5/0.92]? Eccentricity
226- 236 E11.6 --- e_e [9.6e-6/0.25]? e uncertainty
238- 249 E12.6 deg omega [-46/610]? Longitude of periastron
251- 261 E11.6 deg e_omega [0.01/270]? omega uncertainty
263- 274 E12.6 km/s VelOrb [-117.2/243]? Barycenter velocity from an
orbital fit
276- 286 E11.6 km/s e_VelOrb [3.7e-4/6.3]? VelOrb uncertainty
288- 298 E11.6 km/s K1 [7.2/173]? Semiamplitude of the velocity for
component 1
300- 310 E11.6 km/s e_K1 [6.7e-4/71]? K1 uncertainty
312- 322 E11.6 km/s K2 [10.9/169]? Semiamplitude of the velocity for
component 2
324- 334 E11.6 km/s e_K2 [7.9e-4/40]? K2 uncertainty
336- 357 E22.17 Msun M1sin3i [2.7e-4/4.8]? Inclination-dependent mass of
component 1
359- 380 E22.17 Msun e_M1sin3i [6.4e-6/5.3]? M1sin3i uncertainty
382- 403 E22.17 Msun M2sin3i [1.08e-5/0.9]? Inclination-dependent mass of
component 2
405- 426 E22.17 Msun e_M2sin3i [5.4e-6/5.4]? M2sin3i uncertainty
428- 449 E22.17 AU asini [1.4e-3/1.25]? Inclination-dependent
semi-major axis
451- 472 E22.17 AU e_asini [3.1e-7/0.3]? asini uncertainty
474- 495 E22.17 km/s MaxdRV [18.3/407.6] Maximum observed separation in RV
between the primary and the secondary in any
epoch
497- 518 E22.17 km/s AmpRV1 [0/354.4]? Observed amplitude of variation in
radial velocity of component 1 across all of
the available data
520- 541 E22.17 km/s AmpRV2 [0/387.5]? Observed amplitude of variation in
radial velocity of component 2 across all of
the available data
543- 564 E22.17 d MaxT [0.06/2979]? Maximum temporal baseline
566 A1 --- fLOS Line-of-sight coincidence flag
(F=False, T=True) (1)
568 A1 --- fVar Flag for a variable light curve in TESS data
(2)
570- 591 E22.17 d PerTESS [0.22/172]? Period derived from TESS light
curves for periodic variables
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Note (1): Flags as follows:
T = Likely line-of-sight coincidence, defined as having the total radial
velocity change for each component of less than 5 km/s (286 occurrences)
F = Unlikely to be a line-of-sight coincidence (7819 occurrences)
Note (2): Flags as follows:
f = in TESS footprint (3981 occurrences)
v = variable (1135 occurrences)
d = detached eclipsing (369 occurrences)
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Byte-by-byte Description of file:table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- ID APOGEE identifier
20- 41 E22.17 d HJD [55804/58933] Heliocentric Julian Date;
HJD-2400000
43- 65 E23.17 km/s RV1 [-317.9/327.4]? Radial velocity of component 1
67- 88 E22.17 km/s e_RV1 [0/170]? RV1 uncertainty
90- 112 E23.17 km/s RV2 [-302.4/329.7]? Radial velocity of component 2
114- 135 E22.17 km/s e_RV2 [0/180]? RV2 uncertainty
137- 159 E23.17 km/s RV3 [-3.2e+7/6.8e+9]? Radial velocity of component 3
161- 182 E22.17 km/s e_RV3 [0/2.5e+10]? RV3 uncertainty
184- 206 E23.17 km/s RV4 [-98/157.6]? Radial velocity of component 4
208- 229 E22.17 km/s e_RV4 [0/20]? RV4 uncertainty
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History:
From electronic version of the journal
(End) Robin Leichtnam [CDS] 23-Sep-2025