J/AJ/169/124 Position & radial velocity of six triple systems (Tokovinin, 2025)
Orbits of six triple systems.
Tokovinin A.
<Astron. J., 169, 124 (2025)>
=2025AJ....169..124T 2025AJ....169..124T
ADC_Keywords: Stars, double and multiple; Spectroscopy; Optical;
Radial velocities
Keywords: Visual binary stars ; Trinary stars ; Multiple stars ;
Spectroscopic binary stars
Abstract:
Joint analysis of position measurements and radial velocities of six
triple stellar systems is conducted to determine their inner and/or
outer orbits. Accumulation of such data is needed to study the
architecture of stellar hierarchies and its relation to the formation
mechanisms. The inner periods in the six systems (HIP 11783, 64836,
72423, 84720, 89234, and 105404) range from 0.5d to 44yr. The shortest
outer period of 3.34yr is found in the compact triple HIP 105404 (BS
Ind). The resolved triple system HIP 64836 has comparable inner and
outer periods (5 and 30yr), placing it near the limit of dynamical
stability, while its quasi-circular and coplanar orbits suggest a 1:6
mean motion resonance. The periods in HIP 89234 (44 and ∼450yr) are
also comparable, but the mutual orbit inclination is large, 54°.
Masses of the components are estimated and each system is discussed
individually.
Description:
In the hierarchies studied here, subsystems have been discovered or
resolved by speckle interferometry with the high-resolution camera
(HRCam) working on the 4.1m Southern Astrophysical Research (SOAR)
telescope located in Chile. The latest series of measurements and
references to prior observations can be found in
Tokovinin+2024 (J/AJ/168/28). Image cubes of 200x200 pixels and 400
frames are recorded mostly in the y (543/22nm) and I (824/170nm)
filters with an exposure time of 25ms and a pixel scale of 15mas. For
the outer pairs discovered visually, position measurements at SOAR are
complemented by the historic micrometer and speckle data retrieved
from the WDS database (Mason+2001, B/wds) on my request.
RVs of multiple systems come from various sources. Some stars were
targeted by the CHIRON high-resolution optical echelle spectrometer at
the 1.5m telescope located at Cerro Tololo. Reduced spectra of two
targets obtained with the FEROS fiber echelle spectrograph at the 2.2m
telescope were downloaded from the ESO science archive. The RVs of HIP
72423 (HD 130412) have been monitored as part of the survey of nearby
solar-type stars conducted at the Harvard-Smithsonian Center for
Astrophysics (CfA) using several instruments on different telescopes.
The instruments and data reduction methods are described in our
previous papers (Tokovinin+2017, J/ApJ/838/54;
Tokovinin+2020, J/AJ/160/251).
The Gaia DR3 (Gaia Collab+2021, I/355) gives accurate astrometry based
on 3 yr of data. For close binary stars, the astrometry in DR3 is
either missing or biased by the unmodeled orbital motions.
Questionable astrometry is evidenced by large parallax errors and
large values of the reduced unit weight error (RUWE) parameter. The
bias is reduced for the orbital or acceleration solutions in the Gaia
nonsingle star catalog (Gaia Collab+2022, I/357).
Objects:
----------------------------------------------------------------------------
RA (2000) DE Designation(s) (Period)
----------------------------------------------------------------------------
02 32 05.18 -15 14 41.6 02321-1515 = HIP 11783 (Per=20.7yr)
13 17 28.83 +20 24 20.0 13175+2024 = HIP 64836 (Per=5yr)
14 48 31.71 -17 20 24.9 14485-1720 = HIP 72423 (Per=8yr)
17 19 03.83 -46 38 10.4 17191-4638 = HIP 84720 (Per=0.241yr)
18 12 34.08 -73 40 20.7 18126-7340 = HIP 89234 (Per=45yr)
21 20 59.80 -52 28 40.2 21210-5229 = HIP 105404 (Per=3.347yr)
----------------------------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 77 11 List of Multiple Systems
table2.dat 174 10 Orbital Elements
table3.dat 63 193 Position measurements and residuals
table4.dat 51 145 Radial velocities and residuals
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See also:
B/wds : The Washington Visual Double Star Catalog (Mason+ 2001-2020)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
III/135A : Henry Draper Catalogue & Extension (Cannon+ 1918-1924; ADC 1989)
III/283 : RAVE 6th data release (Steinmetz+, 2020)
V/117A : Geneva-Copenhagen Survey of Solar neighbourhood (Holmberg+, 2007)
J/AJ/129/2420 : Proper motion derivatives of binaries (Makarov+, 2005)
J/PASJ/57/13 : High-dispersion spectra of nearby F-K stars (Takeda+, 2005)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/AJ/139/743 : Speckle interferometry in 2008-09 (Tokovinin+, 2010)
J/AJ/143/10 : 2008-2009 WIYN speckle obs. of binaries. VII. (Horch+, 2012)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/AJ/150/151 : DSSI obs. of binaries. VI. Measures in 2014 (Horch+, 2015)
J/AJ/149/195 : Spectro. of the quadruple system HD 91962 (Tokovinin+, 2015)
J/A+A/596/A116 : Radial velocities of K-M dwarfs (Sperauskas+, 2016)
J/AJ/152/11 : Orbits of four triple stars (Tokovinin, 2016)
J/AJ/153/212 : Obs. of binary stars at the WIYN telescope (Horch+, 2017)
J/ApJ/838/54 : Accurate astrometry & RVs of 4 multiple syst. (Tokovinin+, 2017)
J/ApJ/856/23 : BANYAN. XI. The BANYAN Σ algorithm (Gagne+, 2018)
J/ApJS/235/6 : Updated Multiple Star Catalog (MSC): Dec 2023 (Tokovinin, 2018)
J/AJ/155/160 : Multiple syst.:relative positions & residuals (Tokovinin, 2018)
J/AJ/157/56 : DSSI obs. of binary & trinary star systems (Horch+, 2019)
J/AJ/160/251 : RVs & orbital data, 5 triple stars (Tokovinin+, 2020)
J/AJ/161/144 : Inner & outer orbits in 13 multiple stars syst (Tokovinin, 2021)
J/AJ/162/41 : Speckle interferometry at SOAR in 2020 (Tokovinin+, 2021)
J/AJ/164/58 : Speckle Interferometry at SOAR in 2021 (Tokovinin+, 2022)
J/AJ/165/165 : Positional measurements of 4 triple systems (Tokovinin, 2023)
J/AJ/168/28 : Speckle interferometry at SOAR tel. in 2023 (Tokovinin+, 2024)
Byte-by-byte Description of file:table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- WDS Washington Double Star catalog (B/wds)
designation (HHMMS+DDMM, J2000)
12- 20 A9 --- Name Name of the source or WDS (B/wds) Discover code
22- 27 I6 --- HIP [11759/105404]? Hipparcos (I/311) number
29- 34 I6 --- HD [15767/202947]? HD (III/135) identification
36- 40 F5.2 mag Vmag [4.75/11.06]? Visual magnitude
42- 47 F6.2 mas plx [17.45/113.87]? Parallax
49 A1 --- r_plx Reference on plx (1)
51- 54 I4 mas/yr pmRA [-91/1029]? Proper motion in right ascension
direction (pmRA*cosDE)
56- 62 F7.2 mas/yr pmDE [-254/140] Proper motion in declination
direction
64- 67 F4.2 Msun Mass1 [0.6/1.47]? Component mass
69- 72 F4.2 Msun Mass2 [0.42/0.77]? Component mass
74- 77 F4.2 Msun Mass3 [0.55/0.55]? Component mass
--------------------------------------------------------------------------------
Note (1): Reference as follows:
G = Gaia DR3 catalog (I/355); 7 occurrences
H = Hipparcos catalog (I/311); 1 occurrence
D = Dynamical; 1 occurrence
--------------------------------------------------------------------------------
Byte-by-byte Description of file:table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- WDS Washington Double Star catalog (B/wds)
designation (HHMMS+DDMM, J2000)
12- 17 I6 --- HIP [11783/105404]? Hipparcos (I/311) number
19- 23 A5 --- Comp Component designation
25 A1 --- f_Per Flag, *=Per was fixed
27- 36 F10.5 yr Per [0.24/2000] Orbital period
38- 44 F7.4 yr e_Per [1.5e-3/68.7]? Per uncertainty
46- 53 F8.3 yr T [1368/2148] Time of periastron
55- 60 F6.3 yr e_T [7e-3/40] T uncertainty
62 A1 --- f_e Flag, *=e was fixed
64- 68 F5.3 --- e [0/0.86] Eccentricity
70- 74 F5.3 --- e_e [6e-3/0.04]? e uncertainty
76 A1 --- f_a Flag, *=a was fixed
78- 84 F7.4 arcsec a [0.027/12.8] Separation
86- 91 F6.4 arcsec e_a [5e-4/0.55]? a uncertainty
93- 98 F6.2 deg OmegaA [23.1/320.2] Longitude of ascending node (1)
100- 104 F5.2 deg e_OmegaA [0.3/14.8] OmegaA uncertainty
106 A1 --- f_omegaA Flag, *=omegaA was fixed
108- 113 F6.2 deg omegaA [0/357.2] Argument of periastron (1)
115- 119 F5.2 deg e_omegaA [0.9/31.1]? omegaA uncertainty
121 A1 --- f_i Flag, *=i was fixed
123- 128 F6.2 deg i [35.2/143.2] Inclination
130- 133 F4.2 deg e_i [0.4/4.9]? i uncertainty
135 A1 --- f_K1 Flag, *=K1 was fixed
137- 142 F6.3 km/s K1 [1.4/13.8]? Radial velocity amplitude of
primary component
144- 148 F5.3 km/s e_K1 [0.06/0.4]? K1 uncertainty
150 A1 --- f_K2 Flag, *=K2 was fixed
152- 155 F4.2 km/s K2 [2.15/7.33]? Radial velocity amplitude of
secondary component
157- 160 F4.2 km/s e_K2 [0.35/0.35]? K2 uncertainty
162 A1 --- f_V0 Flag, *=V0 was fixed
164- 169 F6.2 km/s V0 [-28.85/10.62]? Center of mass velocity
171- 174 F4.2 km/s e_V0 [0.06/0.1]? V0 uncertainty
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Note (1): When both positions and RVs are available, the argument of periastron
ωA is chosen to represent the RVs of the primary component, and the
node ΩA gives the correct positions of the secondary; adding 180°
to both elements does not affect the positions.
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- WDS Washington Double Star catalog (B/wds)
designation (HHMMS+DDMM, J2000) (1)
12- 16 A5 --- Comp Component designation (2)
18- 26 F9.4 yr Date [1875/2025] Date (Julian year)
28- 32 F5.1 deg PA [4.5/355.2] Position angle
34- 40 F7.4 arcsec Sep [0.02/10.5] Angular separation
42- 47 F6.4 arcsec e_Sep [0.002/0.5] Uncertainty in Sep
49- 53 F5.1 deg (O-C)PA [-13.9/11.7] Residual in PA
55- 61 F7.4 arcsec (O-C)Sep [-0.6/0.45] Residual in Sep
63 A1 --- Meth Measurement method (3)
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Note (1): Objects as follows:
02321-1515 = HIP 11783 (10 occurrences)
13175+2024 = HIP 64836 (21 occurrences)
14485-1720 = HIP 72423 (31 occurrences)
17191-4638 = HIP 84720 (80 occurrences)
18126-7340 = HIP 89234 (37 occurrences)
21210-5229 = HIP 105404 (14 occurrences)
Note (2): For example, A,BC refers to the angle and separation between A and
unresolved pair BC, while A,B refers to the position of the resolved
component B relative to A.
Note (3): Measurement methods as follows:
G = Gaia (I/355, I/357, I/345); 4 occurrences
H = Hipparcos (I/311); 4 occurrences
M = Visual micrometer measurement; 49 occurrences
P = Photographic measurement; 36 occurrences
S = Speckle interferometry with the high-resolution camera (HRCam) working
on the 4.1m Southern Astrophysical Research (SOAR) telescope located
in Chile; 93 occurrences
s = Speckle interferometry at other telescopes; 7 occurrences
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- WDS Washington Double Star catalog (B/wds)
designation (HHMMS+DDMM, J2000) (1)
12- 13 A2 --- Comp Component designation
15- 24 F10.4 d JD [45873/60543] Date (Julian day - 2400000)
26- 32 F7.3 km/s RVel [-30.4/32.6] Radial velocity
34- 38 F5.3 km/s e_RVel [0.06/9.9] Uncertainty in RVel
40- 45 F6.3 km/s O-C [-2.9/2.4]? Residual
47- 51 A5 --- Instr Instrument (2)
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Note (1): Objects as follows:
02321-1515 = HIP 11783 (10 occurrences)
13175+2024 = HIP 64836 (10 occurrences)
14485-1720 = HIP 72423 (84 occurrences)
21210-5229 = HIP 105404 (41 occurrences)
Note (2): Instruments as follows:
CHI = CHIRON high-resolution optical echelle spectrometer at the 1.5m
telescope located at Cerro Tololo, Chile; 21 occurrences
CfA = CfA digital speedometers; 69 occurrences
COR = the CORrelation-RAdial-VELocities (CORAVEL) instrument on the
Danish 1.54m telescope in La Silla, Chile; 21 occurrences
DR2 = Gaia DR2 (I/345); 1 occurrence
G2005 = Guenther+ (2005A&A...433..629G 2005A&A...433..629G); Based on observations obtained at
the European Southern Observatory at La Silla, Chile; 35 occurrences
FEROS = the Fiber-fed Extended Range Optical Spectrograph (FEROS), a
high-resolution, environmentally controlled, astronomical Echelle
spectrograph operated at the European Southern Observatory (ESO)
in La Silla, Chile; 3 occurrences
RAVE = Steinmezt+2020 (III/283); The RAVE (RAdial Velocity Experiment) is
a multi-fiber spectroscopic astronomical survey of stars in the
Milky Way using the 1.2m UK Schmidt Telescope in Autralia;
1 occurrence
TRES = the Tillinghast Reflector Echelle Spectrograph (TRES), a fiber-fed
optical echelle spectrograph on the 1.5m Tillinghast telescope at
the Whipple Observatory in Arizona, US; 8 occurrences
T2005 = Takeda+2005 (J/PASJ/57/13); Using the HIgh-Dispersion Echelle
Spectrograph (HIDES) at the coude focus of the 188cm reflector at
Okayama Astrophysical Observatory, Japan; 3 occurrences
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History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 08-Dec-2025