# Visual Orbits of Spectroscopic Binaries with the CHARA Array. IV.
HD 61859, HD 89822, HD 109510, and HD 191692

Kathryn V. Lester NASA Ames Research Center, Moffett Field, CA 94035, USA
Gail H. Schaefer The CHARA Array of Georgia State University, Mount Wilson
Observatory, Mount Wilson, CA 91023, USA  Francis C. Fekel Center of
Excellence in Information Systems, Tennessee State University, Nashville, TN
37209, USA  Douglas R. Gies Center for High Angular Resolution Astronomy and
Department of Physics & Astronomy, Georgia State University, Atlanta, GA
30302, USA  Todd J. Henry RECONS Institute, Chambersburg, PA 17201, USA  Wei-
Chun Jao Department of Physics & Astronomy, Georgia State University, Atlanta,
GA 30302, USA  Leonardo A. Paredes Department of Physics & Astronomy, Georgia
State University, Atlanta, GA 30302, USA  Hodari-Sadiki Hubbard-James
Department of Physics & Astronomy, Georgia State University, Atlanta, GA
30302, USA  Christopher D. Farrington The CHARA Array of Georgia State
University, Mount Wilson Observatory, Mount Wilson, CA 91023, USA  Kathryn D.
Gordon University of Tampa, Tampa, FL 33606, USA  S. Drew Chojnowski
Department of Physics, Montana State University, Bozeman, MT 59717, USA  John
D. Monnier Department of Astronomy, University of Michigan, Ann Arbor, MI
48109, USA  Stefan Kraus Astrophysics Group, Department of Physics &
Astronomy, University of Exeter, Exeter, EX4 4QL, UK  Jean-Baptiste Le Bouquin
Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France  Narsireddy Anugu
The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount
Wilson, CA 91023, USA  Theo ten Brummelaar The CHARA Array of Georgia State
University, Mount Wilson Observatory, Mount Wilson, CA 91023, USA  Claire L.
Davies Astrophysics Group, Department of Physics & Astronomy, University of
Exeter, Exeter, EX4 4QL, UK  Tyler Gardner Department of Astronomy, University
of Michigan, Ann Arbor, MI 48109, USA  Aaron Labdon European Southern
Observatory, Casilla 19001, Santiago 19, Chile  Cyprien Lanthermann The CHARA
Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA
91023, USA  Benjamin R. Setterholm Department of Astronomy, University of
Michigan, Ann Arbor, MI 48109, USA Kathryn Lester<EMAIL_ADDRESS>
###### Abstract

We present the visual orbits of four spectroscopic binary stars, HD 61859, HD
89822, HD 109510, and HD 191692, using long baseline interferometry with the
CHARA Array. We also obtained new radial velocities from echelle spectra using
the APO 3.5 m, CTIO 1.5 m, and Fairborn Observatory 2.0 m telescopes. By
combining the astrometric and spectroscopic observations, we solve for the
full, three-dimensional orbits and determine the stellar masses to $1-12$%
uncertainty and distances to $0.4-6$% uncertainty. We then estimate the
effective temperature and radius of each component star through Doppler
tomography and spectral energy distribution analyses. We found masses of
$1.4-3.5M_{\odot}$, radii of $1.5-4.7R_{\odot}$, and temperatures of
$6400-10300$K. We then compare the observed stellar parameters to the
predictions of the stellar evolution models, but found that only one of our
systems fits well with the evolutionary models.

binaries: spectroscopic, binaries: visual, stars: fundamental parameters

††facilities: APO:3.5m, CHARA, CTIO:1.5m, TSU:AST††software:  Grid Search for
Binary Stars (Schaefer et al., 2016), MESA (Paxton et al., 2011), RVFIT
(Iglesias-Marzoa et al., 2015), SearchCal (Chelli et al., 2016), TODCOR
(Zucker & Mazeh, 1994), Yonsei-Yale models (Demarque et al., 2004)

##  1 Introduction

We continue our paper series of determining the visual orbits of spectroscopic
binary stars with long baseline interferometry – Paper I (Lester et al.,
2019a), Paper II (Lester et al., 2019b), and Paper III (Lester et al., 2020) –
in order to determine the fundamental stellar parameters of the components.
Precise fundamental parameters of binary systems are essential for determining
orbital demographics (Raghavan et al., 2010; Bordier et al., 2022), testing
models of stellar structure and evolution (e.g., Claret & Torres, 2018;
Morales et al., 2022), calibrating mass and distance determination methods for
single stars (Torres et al., 2010; Chaplin & Miglio, 2013; Gallenne et al.,
2018), and studying how binary stars form and evolve (e.g., Richardson et al.,
2021). In this paper, we present the results for the more massive binaries, HD
61859, HD 89822, HD 109510, and HD 191692. Higher mass stars evolve rather
quickly, so matching the observed parameters of both components at the same
age becomes more challenging for evolutionary models.

HD 61859 (HR 2962, HIP 37580) consists of a pair of F-type stars in a 32 day
orbit. The first spectroscopic orbit was measured by Harper (1926), then more
recently updated by Tomkin & Fekel (2008) using high resolution echelle
spectra.

HD 89822 (ET UMa, HR 4072, HIP 50933) is a well-studied binary consisting of
an early A-type star and an early F-type star in a 12 day orbit. Spectroscopic
orbits were determined by Schlesinger (1912) and Nariai (1970). The primary
component of HD 89822 was identified as a Mercury-Manganese (HgMn) star (Abt &
Snowden, 1973), the higher mass cousins of metallic line (Am) stars. Adelman
(1994) completed a detailed abundance analysis of the system to confirm this
classification and found that the secondary is an Am star (see also Chojnowski
et al., 2020). The TESS light curve of HD 89822 also shows a heartbeat pattern
(Kochukhov et al., 2021; Kołaczek-Szymański et al., 2021), which is a
brightening near periastron due to tidal distortion in close eccentric
binaries (Thompson et al., 2012), but the system shows no evidence of the
rotational modulation found in some HgMn stars (Kochukhov et al., 2021).

HD 109510 (24 Com B, HR 4791, HIP 61415) contains a pair of A-type stars in a
7 day orbit. HD 109510 has been studied spectroscopically by Petrie (1937) and
Mayor & Mazeh (1987). HD 109510 also has a bright visual companion, HD 109511
(24 Com A), at a separation of 20″. This star has a similar proper motion,
radial velocity, and parallax to HD 109510, so they are likely physically
associated. However, HD 109511 is beyond the fields-of-view of our telescopes
and will not affect our observations. The timescales of the inner orbits are
also much shorter than that of the outer pair, so HD 109511 would not cause
visible perturbations in the orbit of HD 109510.

HD 191692 ($\theta$ Aql, HR 7710, HIP 99473) contains a pair of late B-type
stars in a 17 day orbit. A spectroscopic orbit was measured by Cesco & Struve
(1946) and a visual orbit was measured by Hummel et al. (1995) using the Mark
III interferometer; Pourbaix (2000) later used these observations to determine
a combined (VB+SB2) orbital fit. However, these observations lack the high
spectral and angular resolution of modern day echelle spectrographs and long
baseline interferometers, so new observations will provide more precise
results. In addition, a detailed abundance analysis of HD 191692 was completed
by Adelman et al. (2015), which found the primary component to have solar
abundances and the secondary component to be weakly metallic lined.

In Section 2, we present our spectroscopic observations and radial velocities.
In Section 3, we describe our interferometric observations, binary position
measurements, and combined orbital solution. In Section 4, we determine the
fundamental stellar parameters of each component and compare the results to
stellar evolution models. Finally, we discuss our results in Section 5.

##  2 Spectroscopy

###  2.1 APO Observations

We observed HD 61859, 89822, and 109510 with the ARC echelle spectrograph
(ARCES; Wang et al., 2003) on the APO 3.5 m telescope from 2015–2020. ARCES
covers 3500-10500 Å over 107 orders at an average resolving power of $R\sim
30,000$. We reduced our data using standard echelle procedures in IRAF, then
removed the blaze function using the procedure in Appendix A of Kolbas et al.
(2015). Radial velocities ($V_{r1}$, $V_{r2}$) were measured with the multi-
order TODCOR method (Zucker & Mazeh, 1994; Zucker et al., 2003) as described
in Paper II. In summary, TODCOR calculates the cross correlation function
(CCF) for a grid of primary and secondary radial velocities. The CCFs for each
echelle order were added together to find the maximum CCF, corresponding to
the best-fit radial velocities and their uncertainties
($\sigma_{1},\sigma_{2}$). Templates were created with the use of BLUERED
model spectra (Bertone et al., 2008) and atmospheric parameters from recent
literaure. Our observations are listed in Table 5 in the Appendix with the UT
date, HJD date, radial velocity and uncertainty of each component, and the
telescope used. TODCOR also calculates the monochromatic flux ratio
($f_{2}/f_{1}$) near H$\alpha$, which we use later to estimate the radius
ratio for each system (see Section 4.3).

###  2.2 CTIO Observations

We observed HD 109510 and 191692 with the CHIRON echelle spectrograph
(Tokovinin et al., 2013; Paredes et al., 2021) on the CTIO/SMARTS 1.5m
telescope from 2014–2020. HD 109510 was observed in the $R\sim 28,000$ fiber
mode and HD 191692 was observed in the $R\sim 90,000$ slicer mode. Both modes
cover 4500-8800 Å over 60 echelle orders. The data were reduced with the
CHIRON team’s pipeline, then we used the above procedure to remove the blaze
function and measure radial velocities of each component. These observations
are also listed in Table 5.

###  2.3 Fairborn Observations

We also acquired spectroscopic observations of all four binaries at Fairborn
Observatory in southeast Arizona with the Tennessee State University 2.0 m
Automatic Spectroscopic Telescope (AST) and a fiber-fed echelle spectrograph
(Eaton & Williamson, 2004). We obtained spectra of HD 61859 from 2011–2020 as
a continuation of the velocities published by Tomkin & Fekel (2008). We
collected spectra of HD 89822 from 2005–2020, HD 109510 from 2020–2021, and of
HD 191692 from 2004–2021. The observations of HD 89822 and HD 191692 that were
obtained before 2011 were acquired with a 2048 $\times$ 4096 SITe ST-002A CCD.
Those spectra have 21 orders, cover a wavelength region of 4920–7100 Å, and
have $R\sim 35,000$ at 6000 Å. During the summer of 2011 we replaced the SITe
CCD with a Fairchild 486 CCD that has a 4096 $\times$ 4096 pixel array
enabling coverage of a wavelength range of 3800–8600 Å over 48 orders (Fekel
et al., 2013). We used a 200 $\mu$m fiber that produced $R\sim 25,000$ at 6000
Å. Eaton & Williamson (2007) explained the data reduction and wavelength
calibration of the raw AST spectra.

Fekel et al. (2009) provided a general description of the typical velocity
reduction. Briefly, for HD 61859 and HD 109510 we used a solar-type star line
list consisting of 168 mostly neutral Fe lines in the wavelength region
4920–7100 Å. The early-A and late-B spectral classes of the components of HD
89822 and HD 191692 required the use of our A-star line list. The lines in
that list cover the same wavelength region as the solar-type line list but
mainly include ionized Fe lines. Each line was fitted with a rotational
broadening function (Sandberg Lacy & Fekel, 2011), and if the lines of the two
components were partly blended we obtained a simultaneous fit. The stellar
velocity was determined as the average of the line fits. A value of 0.3 km s-1
was added to the SITe CCD velocities and 0.6 km s-1 to the Fairchild CCD
velocities to make the resulting velocities from the two CCDs consistent with
the velocity zero point of Scarfe (2010). These observations are also listed
in Table 5.

###  2.4 Preliminary Spectroscopic Orbit

Following the procedure in previous papers, we accounted for differences in
the zero-point offset of each spectrograph by first fitting separate orbital
solutions to each data set using the RVFIT
program111http://www.cefca.es/people/$\sim$riglesias/rvfit.html (Iglesias-
Marzoa et al., 2015). We solved for the six spectroscopic orbital parameters
of each system: the orbital period ($P$), epoch of periastron ($T$),
eccentricity ($e$), longitude of periastron of the primary star
($\omega_{1}$), velocity semi-amplitudes ($K_{1}$, $K_{2}$), and systemic
velocity ($\gamma$). We also fit an orbit to the previously published
velocities of HD 61859 from Tomkin & Fekel (2008) using preliminary
uncertainties equal to $1/\sqrt{weight}$. We shifted the APO, CTIO, and
literature data sets such that the systemic velocities match those of the
Fairborn data sets. We then used the $\chi^{2}$ values from the individual
solutions to rescale the uncertainties such that the reduced $\chi^{2}$ of
each data set equals one. Our adjusted velocities and rescaled uncertainties
are those listed in Table 5 in the Appendix.

##  3 Interferometry

Table 1: Relative Positions  Target | UT Date | HJD-2,400,000 | $\rho$ | $\theta$ | $\sigma_{maj}$ | $\sigma_{min}$ | $\phi$ | $f_{2}/f_{1}$ | Beam
---|---|---|---|---|---|---|---|---|---
|  |  | (mas) | (deg) | (mas) | (mas) | (deg) |  | Combiner
HD 61859 | 2013 Dec 11 | 56638.0297 | 2.531 | 63.3 | 0.253 | 0.056 | 83.6 | 0.410 $\pm$ 0.003 | CLIMB
HD 61859 | 2017 Feb 01 | 57785.7409 | 3.719 | 242.1 | 0.169 | 0.101 | 51.7 | 0.406 $\pm$ 0.009 | CLIMB
HD 61859 | 2017 Nov 30 | 58087.8801 | 2.961 | 60.5 | 0.171 | 0.092 | 130.9 | 0.390 $\pm$ 0.005 | CLIMB
HD 61859 | 2018 Dec 12 | 58464.8835 | 2.494 | 63.4 | 0.171 | 0.083 | 56.2 | 0.431 $\pm$ 0.014 | CLIMB
HD 61859 | 2019 Sep 18 | 58745.0249 | 0.430 | 140.0 | 0.226 | 0.226 | 144.5 | 0.574 $\pm$ 0.180 | CLIMB
HD 61859 | 2019 Dec 21 | 58838.8581 | 0.696 | 194.7 | 0.270 | 0.115 | 57.8 |  $\cdots$ | CLIMB
HD 61859 | 2021 Mar 28 | 59301.6728 | 5.027 | 237.4 | 0.001 | 0.001 | 153.4 | 0.3852 $\pm$ 0.0002 | MIRC-X
HD 89822 | 2017 Nov 30 | 58088.0567 | 1.884 | 282.1 | 0.131 | 0.104 | 28.3 | 0.214 $\pm$ 0.008 | CLIMB
HD 89822 | 2018 Apr 10 | 58218.7122 | 1.002 | 166.8 | 0.110 | 0.027 | 164.4 | 0.232 $\pm$ 0.002 | CLIMB
HD 89822 | 2018 Apr 11 | 58219.7138 | 1.128 | 122.2 | 0.115 | 0.058 | 100.1 | 0.231 $\pm$ 0.004 | CLIMB
HD 89822 | 2018 Nov 26 | 58449.0307 | 1.206 | 227.7 | 0.063 | 0.049 | 153.5 | 0.263 $\pm$ 0.005 | CLIMB
HD 89822 | 2018 Dec 12 | 58464.9750 | 1.315 | 22.7 | 0.069 | 0.059 | 150.6 | 0.267 $\pm$ 0.005 | CLIMB
HD 89822 | 2019 Apr 25 | 58598.7623 | 1.386 | 259.3 | 0.067 | 0.034 | 110.4 | 0.339 $\pm$ 0.011 | CLIMB
HD 89822 | 2019 Apr 26 | 58599.6880 | 1.207 | 224.8 | 0.082 | 0.050 | 43.0 | 0.396 $\pm$ 0.030 | CLIMB
HD 89822 | 2019 Apr 27 | 58600.7010 | 1.060 | 170.9 | 0.114 | 0.058 | 138.3 | 0.245 $\pm$ 0.004 | CLIMB
HD 89822 | 2019 Apr 28 | 58601.7970 | 1.087 | 115.6 | 0.219 | 0.087 | 115.5 | 0.278 $\pm$ 0.007 | CLIMB
HD 89822 | 2019 Dec 20 | 58838.0461 | 2.071 | 322.4 | 0.087 | 0.052 | 72.0 | 0.208 $\pm$ 0.003 | CLIMB
HD 89822 | 2021 Mar 28 | 59301.7480 | 2.106 | 319.5 | 0.001 | 0.001 | 143.1 | 0.2276 $\pm$ 0.0001 | MIRC-X
HD 109510 | 2017 May 20 | 57893.7031 | 0.680 | 167.6 | 0.267 | 0.090 | 161.4 | 0.471 $\pm$ 0.102 | CLIMB
HD 109510 | 2017 May 21 | 57894.7054 | 0.587 | 285.4 | 0.134 | 0.066 | 111.5 | 0.458 $\pm$ 0.065 | CLIMB
HD 109510 | 2019 Apr 26 | 58599.8104 | 0.831 | 319.7 | 0.027 | 0.014 | 136.6 | 0.561 $\pm$ 0.011 | CLIMB
HD 109510 | 2019 Apr 27 | 58600.8133 | 0.689 | 354.2 | 0.041 | 0.021 | 102.5 | 0.579 $\pm$ 0.015 | CLIMB
HD 109510 | 2021 Mar 28 | 59301.8264 | 0.935 | 146.8 | 0.001 | 0.001 | 168.7 | 0.5285 $\pm$ 0.0002 | MIRC-X
HD 191692 | 2012 Sep 04 | 56174.6984 | 1.375 | 296.1 | 0.383 | 0.240 | 130.9 | 0.181 $\pm$ 0.012 | CLIMB
HD 191692 | 2017 Sep 08 | 58004.6859 | 2.795 | 17.7 | 0.236 | 0.236 | 121.0 | 0.235 $\pm$ 0.001 | CLIMB
HD 191692 | 2018 Aug 17 | 58347.8136 | 2.308 | 4.8 | 0.248 | 0.136 | 15.9 | 0.260 $\pm$ 0.003 | CLIMB
HD 191692 | 2018 Sep 03 | 58364.6972 | 2.439 | 9.8 | 0.201 | 0.178 | 112.6 | 0.245 $\pm$ 0.004 | CLIMB
HD 191692 | 2018 Sep 05 | 58366.6994 | 1.337 | 287.9 | 0.293 | 0.188 | 141.2 | 0.169 $\pm$ 0.002 | CLIMB
HD 191692 | 2019 Jul 04 | 58668.9676 | 4.383 | 55.8 | 0.007 | 0.002 | 50.2 | 0.238 $\pm$ 0.001 | MIRC-X
HD 191692 | 2019 Sep 16 | 58742.6754 | 1.701 | 330.8 | 0.496 | 0.252 | 41.1 | 0.177 $\pm$ 0.004 | CLIMB
HD 191692 | 2020 Aug 12 | 59073.7005 | 4.111 | 95.3 | 0.006 | 0.002 | 141.9 | 0.2415 $\pm$ 0.0001 | MIRC-X
HD 191692 | 2020 Aug 13 | 59074.6859 | 4.476 | 88.2 | 0.010 | 0.004 | 147.9 | 0.2235 $\pm$ 0.0003 | MIRC-X

###  3.1 CHARA Array Observations

We observed all four binaries with the CHARA Array from 2012–2019 using the
CLIMB (ten Brummelaar et al., 2013) beam combiner and from 2019–2021 using the
MIRC-X (Anugu et al., 2020) beam combiner. CHARA has six 1.0 m telescopes
arranged in a Y-shape with baselines ranging from 34–331 m (ten Brummelaar et
al., 2005). CLIMB combines the $K^{\prime}$-band light from three telescopes
at a time, while MIRC-X combines the $H$-band light from up to six telescopes
and disperses the light into six narrowband spectral channels at $R=50$. Table
1 lists the UT date, HJD, and beam combiner for each CHARA observation. The
CLIMB data were reduced with the pipeline developed by John D. Monnier; the
general method is described in Monnier et al. (2011) and the extension to
three beams is described in Kluska et al. (2018). The MIRC-X data were reduced
using the pipeline (version 1.3.3–1.3.5) developed by Jean-Baptiste Le Bouquin
and the MIRC-X
team222https://gitlab.chara.gsu.edu/lebouquj/mircx_pipeline.git, which splits
each 10 min data sequence into four 2.5 minute bins. These reductions produce
squared visibilities ($V^{2}$) for each baseline and closure phases (CP) for
each closed triangle. We corrected for any instrumental and atmospheric
effects on the observed visibilities using observations of calibrators stars,
whose uniform disk angular diameters were taken from SearchCal (Chelli et al.,
2016) and are listed in Table 6 in the Appendix. On each night, we also
calibrated the calibrators against each other and did not find evidence of
binarity in the calibrators.

Table 2: Orbital Parameters from VB+SB2 Solution  Parameter | HD 61859 | HD 89822 | HD 109510 | HD 191692
---|---|---|---|---
$P$ (days) | $31.500002\pm 0.000056$ | $11.579113\pm 0.000010$ | $7.336673\pm 0.000087$ | $17.124281\pm 0.000038$
$T$ (HJD-2400000) | $58880.701\pm 0.018$ | $57756.168\pm 0.005$ | $59361.967\pm 0.011$ | $58624.154\pm 0.004$
$e$ | $0.1951\pm 0.0007$ | $0.2943\pm 0.0009$ | $0.2585\pm 0.0012$ | $0.6040\pm 0.0009$
$\omega_{1}$ (deg) | $39.52\pm 0.23$ | $176.50\pm 0.20$ | $302.33\pm 0.28$ | $33.73\pm 0.22$
$i$ (deg) | $94.73\pm 3.51$ | $141.87\pm 0.97$ | $61.40\pm 3.89$ | $144.10\pm 0.18$
$\alpha$ (mas) | $4.403\pm 0.003$ | $1.634\pm 0.001$ | $1.007\pm 0.037$ | $3.148\pm 0.002$
$\Omega$ (deg) | $237.81\pm 3.45$ | $133.49\pm 0.13$ | $136.17\pm 2.86$ | $96.92\pm 0.19$
$\gamma$ (km s-1) | $-12.51\pm 0.03$ | $-2.24\pm 0.03$ | $3.51\pm 0.06$ | $-29.26\pm 0.08$
$K_{1}$ (km s-1) | $46.77\pm 0.07$ | $38.17\pm 0.04$ | $68.16\pm 0.09$ | $48.78\pm 0.09$
$K_{2}$ (km s-1) | $52.81\pm 0.03$ | $62.11\pm 0.09$ | $81.28\pm 0.20$ | $63.48\pm 0.11$

###  3.2 Binary Positions

We measured the relative positions from the visibilities and closure phases
using the method333http://www.chara.gsu.edu/analysis-software/binary-grid-
search of Schaefer et al. (2016), which searches across a grid of separations
in right ascension and declination to find the best-fit relative position. At
each grid point, we compared the observed $V^{2}$ and CP to model values to
fit for the flux ratio and calculate the $\chi^{2}$ value. We then searched a
small area around the best-fit position to find the contour marking
$\chi^{2}\leq\chi^{2}_{min}+1$ that determines the major axis
($\sigma_{maj}$), minor axis ($\sigma_{min}$), and position angle ($\phi$) of
each error ellipse. Because the orbital periods of these systems are much
longer than the observation time, any small orbital motion within a single
night is contained within the error ellipses. The best-fit relative positions,
error ellipse parameters, and flux ratio estimates for each night are listed
in Table 1.

We note that the flux ratios are likely underestimated, because they do not
account for systematics in visibility miscalibrations. Furthermore, the more
precise CP of MIRC-X can constrain the flux ratios better than CLIMB, so we
used the flux ratios from the MIRC-X observations to estimate the radius
ratios in Section 4.3. We calculated the uncertainty for a single measurement
from the standard deviation of the flux ratios derived from the three MIRC-X
observations of HD 191692. We used this value as the final uncertainty for HD
61859, HD 89822, and HD 109510, but scaled this value by $\sqrt{3}$ to
calculate the final uncertainty for HD 191692.

For HD 191692, the primary star is large enough to be resolved by CHARA, so we
simultaneously fit the $V^{2}$ and CP for the primary angular diameter
($\theta_{1}$) and the binary parameters. The secondary component is
unresolved, so we held the angular diameter fixed to $\theta_{2}=0$ mas. We
found the weighted-mean, uniform-disk angular diameter to be
$\theta_{1}=0.571\pm 0.017$ mas from our MIRC-X observations. We also tested
limb-darkened models using linear limb-darkening coefficients from Claret
(2000) for the effective temperature and surface gravity found in Section 4.3.
However, the difference between the limb-darkened visibilities and the
uniform-disk visibilities were roughly ten times smaller than the
observational uncertainties, because limb-darkening is very weak in the near
infrared (Davis et al., 2000).

###  3.3 Combined Visual + Spectroscopic Solution

We determined the final orbital solution by simultaneously fitting the
interferometric and spectroscopic data using the
method444https://www.chara.gsu.edu/analysis-software/orbfit-lib of Schaefer et
al. (2016). The full set of orbital parameters includes the orbital period
($P$), epoch of periastron ($T$), eccentricity ($e$), longitude of periastron
of the primary star ($\omega_{1}$), the inclination ($i$), the angular semi-
major axis ($a$), the longitude of the ascending node ($\Omega$), the systemic
velocity ($\gamma$), and the velocity semi-amplitudes ($K_{1}$, $K_{2}$).
Table 2 lists the combined (VB+SB2) orbital solutions for each system. The
visual orbits of all four systems are shown in Figure 1 and the spectroscopic
orbits are shown in Figure 2. To determine the uncertainty of each orbital
parameter, we performed a Monte Carlo error analysis in which we varied each
data point within its Gaussian uncertainty and refit for the orbital solution.
We then made a histogram of the best-fit parameters from $10^{5}$ iterations
and fit Gaussians to each distribution to determine the $1\sigma$
uncertainties in each parameter (also listed in Table 2).

Figure 1: Visual orbits of HD 61859 (top left), HD 89822 (top right), HD
109510 (bottom left), and HD 191692 (bottom right). The primary star is
located at the origin (black cross). The relative positions of the secondary
star from CLIMB data are marked by the gray points corresponding to the sizes
of the error ellipses. The relative positions from MIRC-X data are marked by
black circles with red error ellipses, which are often to small to be seen.
The solid blue curves represent the best-fit model visual orbits, and thin
black lines connect each observed and model position. The arrows indicate the
directions of orbital motion.

Figure 2: Radial velocity curves of HD 61859 (top left), HD 89822 (top right),
HD 109510 (bottom left), and HD 191692 (bottom right). The observed data for
the primary and secondary star are shown with the filled and open points,
respectively. The triangles, diamonds, and circles represent the APO, CTIO,
and Fairborn data, respectively. The model curves are shown with the solid
lines, and the residuals to the fit are shown in the bottom panels.

##  4 Stellar Parameters

###  4.1 Masses and Distance

We calculated the component masses and binary distance from the combined
orbital solution using nominal Solar values from Prša et al. (2016). Our
results are listed in Table 3. The uncertainties in component mass are less
than 1.4% for HD 61859, 5.5% for HD 89822, 11.9% for HD 109510, and 1.4% for
HD 191692. The uncertainties in distance are 0.5% for HD 61859, 2.0% for HD
89822, 5.6% for HD 109510, and 0.4% for HD 191692.

Model independent distance measurements from binary stars are important checks
for other distances measurements, such as the Cepheid period-luminosity
relationship (Gallenne et al., 2018) and trigonometric parallax (Halbwachs et
al., 2016; Stassun & Torres, 2018). We compared our distances from orbital
parallax to the distances from Gaia DR3 parallaxes (Gaia Collaboration et al.,
2016, 2022), which are listed at the end of Table 3. Our distances were
consistent with Gaia’s to within the $1\sigma$ uncertainties for HD 61859, HD
89822, and HD 109510. However, our distance for HD 191692 of $76.3\pm 0.3$ pc
does not match the Gaia distance of $70.1\pm 2.3$ pc. HD 191692 is a very
bright star ($G=3.2$ mag), so the trigonometric parallax could have been
affected by saturation.

Table 3: Astrophysical Parameters  Parameter |  HD 61859 |  HD 89822 |  HD 109510 |  HD 191692
---|---|---|---|---
$M_{1}$ ($M_{\odot}$) | $1.629\pm 0.023$ | $2.779\pm 0.153$ | $1.838\pm 0.218$ | $3.564\pm 0.049$
$M_{2}$ ($M_{\odot}$) | $1.443\pm 0.020$ | $1.708\pm 0.094$ | $1.541\pm 0.184$ | $2.739\pm 0.037$
$R_{1}$ ($R_{\odot}$) | $2.53\pm 0.10$ | $3.16\pm 0.11$ | $2.28\pm 0.06$ | $4.76\pm 0.14$
$R_{2}$ ($R_{\odot}$) | $1.51\pm 0.06$ | $1.73\pm 0.06$ | $1.70\pm 0.07$ | $2.34\pm 0.07$
$T_{\rm eff\ 1}$ (K) | $6390\pm 180$ | $10260\pm 100$ | $7630\pm 120$ | $10300\pm 200$
$T_{\rm eff\ 2}$ (K) | $6610\pm 230$ | $7860\pm 140$ | $7180\pm 140$ | $10230\pm 220$
$\log g_{1}$ (cgs) | $3.85\pm 0.02$ | $3.88\pm 0.05$ | $3.86\pm 0.01$ | $3.64\pm 0.02$
$\log g_{2}$ (cgs) | $4.22\pm 0.02$ | $4.22\pm 0.05$ | $4.09\pm 0.02$ | $4.14\pm 0.02$
$L_{1}$ ($L_{\odot}$) | $9.6\pm 1.3$ | $101.0\pm 8.0$ | $15.6\pm 1.3$ | $229.8\pm 22.5$
$L_{2}$ ($L_{\odot}$) | $4.1\pm 0.5$ | $9.7\pm 1.0$ | $7.2\pm 0.9$ | $54.0\pm 5.8$
$V_{1}\sin i$ (km s-1) | $37.1\pm 1.0$ | $\leq 4.2$ | $14.5\pm 1.5$ | $36.3\pm 0.4$
$V_{2}\sin i$ (km s-1) | $\leq 4.2$ | $5.1\pm 2.1$ | $14.2\pm 1.1$ | $13.6\pm 0.9$
$\log Z_{1}/Z_{\odot}$ (dex) | $-0.05\pm 0.12$ | $0.11\pm 0.04$ | $-0.05\pm 0.02$ | $0.05\pm 0.05$
$\log Z_{2}/Z_{\odot}$ (dex) | $-0.06\pm 0.05$ | $-0.05\pm 0.07$ | $-0.04\pm 0.07$ | $0.12\pm 0.13$
Distance (pc, this work) | $64.4\pm 0.3$ | $101.1\pm 2.0$ | $110.1\pm 6.1$ | $76.3\pm 0.3$
Distance (pc, Gaia DR3) | $64.8\pm 1.9$ | $103.8\pm 1.0$ | $111.8\pm 0.4$ | $70.1\pm 2.3$

###  4.2 Atmospheric Parameters

We reconstructed the spectra of each binary component using the method of
Bagnuolo et al. (1992) as described in Papers I-III. Initial model templates
were created using atmospheric parameters from the recent literature. We then
fit for the effective temperature ($T_{\rm{eff}}$), projected rotational
velocity ($V\sin i$), and metal abundance ($\log Z/Z_{\odot}$) of each
component by cross-correlating a grid of BLUERED model spectra against the
reconstructed spectra. Only echelle orders in the range $4500-6600$Å that
contain strong absorption lines were used. We determined the best-fit
parameters of each component and their uncertainties from the CCF peak, as
listed in Table 3. Example plots of the final reconstructed spectra and best-
fit model spectra are shown in Figures 5-8 in the Appendix. For HD 61859, we
found both components to be slightly metal poor. We found HD 89822 to have a
slightly metal rich primary and a roughly Solar abundance secondary,
consistent with the iron abundances found by Adelman (1994). We also confirm
that the primary component is a HgMn star and the secondary component is an Am
star based on the reconstructed spectra, as shown in Figure 6. Both components
of HD 109510 are also slightly metal poor, but the secondary is consistent
with Solar metallicity within the uncertainties. Finally, we found both
components of HD 191692 to be slightly metal rich, consistent with the iron
abundances found by Adelman et al. (2015).

###  4.3 Radii and Surface Gravities

Figure 3: SEDs of HD 61859 (top left), HD 89822 (top right), HD 109510 (bottom
left), and HD 191692 (bottom right). The observed fluxes are shown in black,
and the best-fit binary model fluxes are shown as the red crosses. The full
binary model is shown in gray. For clarity, we do not show the uncertainties
in the Burnashev (1985) spectra of HD 109510.

We built spectral energy distributions (SEDs) using photometry from the
literature in order to determine the radii of each component. We included UV
photometry from the TD1 Stellar Ultraviolet Fluxes Catalog (Thompson et al.,
1978), optical photometry from the Fourth US Naval Observatory CCD Astrograph
Catalog (UCAC4; Zacharias et al., 2013), and infrared photometry from the Two
Micron All Sky Survey (2MASS; Skrutskie et al., 2006) and the Wide-field
Infrared Survey Explorer (WISE; Wright et al., 2010). The dataset for HD
109510 also includes low resolution, flux calibrated spectroscopy from
Burnashev (1985).

Next, we created surface flux models of each component (Castelli & Kurucz,
2004) based on the $T_{\rm{eff}}$ found above. We estimated the radius ratio
($R_{2}/R_{1}$) of each binary by comparing the model surface flux ratio and
the observed flux ratios near $H\alpha$ (from spectroscopy) and in the
$H$-band (from interferometry). These parameters are listed in Table 4. The
surface flux models were also used to create a combined, binary SED model for
each system. Using the procedure described in Paper III, we fit the binary
model SED to the observed fluxes in order to determine the angular diameter of
the primary star ($\theta_{1}$) and the color excess ($E(B-V)$) of each
system. For HD 191692, we converted the uniform-disk angular diameter of the
primary component measured directly with interferometry to a limb-darkened
disk diameter (Davis et al., 2000), then held this parameter fixed to fit only
for reddening. We then used the radius ratios to calculate the angular
diameters of the secondary stars ($\theta_{2}$). The observed SED’s and best-
fit models are shown in Figure 3, and the best-fit SED parameters are listed
in Table 4.

Finally, we combined the Gaia DR3 distances with the angular diameters to
calculate the component radii, except in the case of HD 191692. The Gaia
parallax of HD 191692 does not agree with our results and has a larger
uncertainty, so we used the distance from orbital parallax instead. Table 3
lists the best-fit stellar radii of each component, the surface gravities
calculated from the masses and radii, and the luminosities calculated from the
Stefan-Boltzmann Law. Our stellar radii have uncertainties less than 4.0% for
HD 61859, 3.6% for HD 89822, 4.1% for HD 109510, and 3.0% for HD 191692.

Table 4: SED Parameters  Parameter |  HD 61859 |  HD 89822 |  HD 109510 |  HD 191692
---|---|---|---|---
$f_{2}/f_{1}$ (6500Å) | $0.45\pm 0.03$ | $0.18\pm 0.07$ | $0.70\pm 0.05$ | $0.25\pm 0.06$
$f_{2}/f_{1}$ ($H$-band) | $0.385\pm 0.007$ | $0.228\pm 0.007$ | $0.526\pm 0.007$ | $0.238\pm 0.004$
$R_{2}/R_{1}$ | $0.60\pm 0.01$ | $0.55\pm 0.01$ | $0.75\pm 0.02$ | $0.49\pm 0.01$
$\theta_{1}$ (mas) | $0.363\pm 0.014$ | $0.291\pm 0.009$ | $0.189\pm 0.005$ |  $0.580\pm 0.017$**Fixed to the limb-darkened angular diameter from CHARA observations
$\theta_{2}$ (mas) | $0.217\pm 0.009$ | $0.159\pm 0.005$ | $0.142\pm 0.007$ | $0.285\pm 0.009$
$E(B-V)$ | $0.05\pm 0.01$ | $0.01\pm 0.02$ | $0.01\pm 0.01$ | $0.00\pm 0.01$

###  4.4 Comparison with Evolutionary Models

We created evolutionary tracks for the components of each binary system using
the Yonsei-Yale (Demarque et al., 2004) and MESA (Paxton et al., 2011, 2019)
codes in order to estimate the system ages and test the predictions of these
models. We started with the observed masses and $\log Z/Z_{\odot}$ values from
Table 3. The Yonsei-Yale models use a fixed overshooting parameter calculated
from a step function in stellar mass. For the MESA models, we used the
overshooting parameter ($f_{\rm ov}$) from the relation found by Claret &
Torres (2018) and the default mixing length parameter of $\alpha_{\rm
ov}=2.0$, but adjusted $f_{\rm ov}$ and $\alpha_{\rm ov}$ slightly as needed
to fit the observed parameters. Both models are non-rotating and use scaled
Solar abundances.

Figure 4 shows the model evolutionary tracks and observed parameters of each
binary system. For each component, we determined the age range where the model
lies within the observed $1\sigma$ uncertainties. If the model lies outside
the observed data point, we tried the $2\sigma$ uncertainties instead. If the
component ages matched (to within 5%), we took a weighted average to estimate
the binary system age, where the mean values corresponded to the best-fit age
of each component and the uncertainties corresponded to the spread in possible
ages. As described below, the component ages often did not match, so we
adopted the primary star’s age as the system age because it evolves faster and
provides a tighter age constraint. The estimated binary ages are marked on
each evolutionary track by a cross in Figure 4.

Figure 4: Evolutionary tracks for HD 61859 (top left), HD 89822 (top right),
HD 109510 (bottom left), and HD 191692 (bottom right). The observed stellar
parameters are shown as the filled points for the primary stars and open
points for the secondary stars. The Yonsei-Yale models are shown as dashed
lines and the MESA models are shown as solid lines, with green for the primary
and blue for the secondary. The crosses represent the position of the mean
system age on each track.

HD 61859 – The Yonsei-Yale models match the observed parameters of the primary
component at age of 1.90 Gyr near the end of the main sequence, but lie just
outside the observed parameters of the secondary at an age of 1.50 Gyr. The
MESA models match the observed parameters of the primary component at age of
1.60 Gyr, but lie just outside the observed parameters of the secondary at an
age of 1.10 Gyr. The observed parameters of the primary are not consistent
with either model at the age of the secondary, so we adopted the primary
star’s mean age of 1.75 Gyr as the age for the system. A Solar-abundance
evolutionary model would fit the secondary component better, despite being
inconsistent with our spectroscopic analysis. Therefore, HD 61859 would
benefit from a detailed abundance analysis to investigate whether or not the
secondary component is chemically peculiar and solve this discrepancy.

HD 89822 – The primary component is hotter and larger than predicted by both
the Yonsei-Yale and MESA models. The closest position on the Yonsei-Yale
tracks corresponds to 330 Myr, whereas the secondary component has an age of
510 Myr. The closest position on the MESA tracks corresponds to 300 Myr,
whereas the secondary component has an age of 400 Myr. We adopted the primary
star’s mean age of 315 Myr for the system, because the primary star would be
too evolved at the predicted ages of the secondary star. The primary component
likely does not match the models because it is a HgMn star; its abundance
anomalies could bias our temperature determination from Section 4.2 and our
comparison to evolutionary models, because the BLUERED and MESA models both
use scaled solar abundances. Because this system is quite young, we checked
for membership in several nearby moving groups and associations using the
BANYAN $\Sigma$ tool (Gagné et al., 2018), but HD 89822 had a 99.9% chance of
being a field star.

HD 109510 – The Yonsei-Yale models successfully fit both components at an age
of 1.04 Gyr, and the MESA models successfully fit both components at an age of
930 Myr using $f_{\rm ov}$ from Claret & Torres (2018) and the default
$\alpha_{\rm ov}$ parameter. Even though this system has large uncertainties
in stellar mass, our results are likely still accurate because the component
effective temperatures and radii fit quite well.

HD 191692 – Both components of HD 191692 are slightly cooler and smaller than
predicted by the Yonsei-Yale and MESA models. The primary component has
evolved to the end of the main sequence; the closest model track point
corresponds to an age of 220 Myr for the Yonsei-Yale models and 210 Myr for
the MESA models. The closest track points to the secondary correspond to an
age of 170 Myr for the Yonsei-Yale models and 190 Myr for the MESA models.
Even though these are very close to the ages of the primary star, the primary
evolves much faster and would only be halfway up the main sequence at these
ages. Therefore, we adopt the primary star’s mean age of 215 Myr as the
estimated age of the binary. Note that Adelman et al. (2015) derived similar
component effective temperatures from their abundance analysis, so perhaps the
observed radii are underestimated and causing this age discrepancy. While the
primary star is just barely resolved by our MIRC-X observations, its angular
diameter would be well above the resolution limit at shorter wavelengths, so
future interferometric observations would help solve this discrepancy between
the observed and model parameters. Finally, we also checked if HD 191692 could
be in young association using BANYAN $\Sigma$, but HD 191692 had a 99.9%
chance of being a field star.

##  5 Discussion

We measured the visual and spectroscopic orbits for four binary systems using
long baseline interferometry and high resolution spectroscopy. We constrained
the stellar masses to $1-12$% uncertainty, distances to $0.4-6$% uncertainty,
and stellar radii to $3-5$% uncertainty. These fundamental parameters of
longer period binaries ($P>7$d) are especially useful for testing our stellar
models, because the component stars are less affected by tidal interactions
and distortions and are better proxies for the evolution of single stars
(Serenelli et al., 2021).

Typically, uncertainties in mass and radius less than 3% are needed to test
our models of stellar structure and evolution (Torres et al., 2010). HD 61859
and HD 191692 meet this criterion for stellar mass, while additional
observations with long baseline interferometry would be needed to more
precisely measure the orbital inclinations and stellar masses of HD 89822 and
HD 109510. HD 191692 also meets this criterion for stellar radius, because the
primary’s angular diameter was measured more precisely with the CHARA Array.
We estimate that both components of HD 61859, the primary component of HD
89822, and both components of HD 191692 are resolvable with CHARA in visible
light, so future work to measure directly the component radii would greatly
improve the comparison with stellar evolution models.

We also found that HD 61859 is highly inclined and could create grazing
eclipses. The TESS light curve potentially shows a very weak eclipse (0.1%
depth) when the secondary star passes front of the primary star. However, no
complementary eclipses were seen, and each TESS sector only covers two-thirds
of the binary orbit, so additional observations would be needed to confirm
this system as an eclipsing binary.

Finally, the MESA models did not adequately fit the observed parameters of the
chemically peculiar stars, HD 89822 and HD 191962, likely because their
abundances are not scaled Solar values. Abt (1961) found that the metallic
line phenomenon is linked to binarity, so further study of these systems could
improve our understanding of the structure and evolution of HgMn and Am stars.

The authors would like to thank the staff at APO, CHARA, CTIO, and Fairborn
Observatory for their invaluable support during observations. K.V.L. is
supported by an appointment to the NASA Postdoctoral Program at the NASA Ames
Research Center, administered by Oak Ridge Associated Universities under
contract with NASA. This work is based upon observations obtained with the
Apache Point Observatory 3.5-meter telescope, owned and operated by the
Astrophysical Research Consortium; the Georgia State University Center for
High Angular Resolution Astronomy Array at Mount Wilson Observatory, supported
by the National Science Foundation under Grants No. AST-1636624, AST-1908026,
& AST-2034336; and the CTIO/SMARTS 1.5m telescope, operated as part of the
SMARTS Consortium. Institutional support has been provided from the GSU
College of Arts and Sciences and the GSU Office of the Vice President for
Research and Economic Development. MIRC-X received funding from the European
Research Council (ERC) under the European Union’s Horizon 2020 research and
innovation programme (Grant No. 639889). J.D.M. acknowledges funding for the
development of MIRC-X (NASA-XRP NNX16AD43G, NSF-AST 1909165). S.K.
acknowledges support from an ERC Consolidator Grant (Grant Agreement ID
101003096) and STFC Consolidated Grant (ST/V000721/1). Astronomy at Tennessee
State University is supported by the state of Tennessee through its Centers of
Excellence Program. This work has also made use of the Jean-Marie Mariotti
Center Aspro & SearchCal services, the CDS Astronomical Databases SIMBAD and
VIZIER, the Wide-field Infrared Survey Explorer, and the Two Micron All Sky
Survey.

Table 5:  Radial Velocity Measurements  Target | UT Date | HJD-2,400,000 | $V_{r\ 1}$ | $\sigma_{1}$ | $V_{r\ 2}$ | $\sigma_{2}$ | Source
---|---|---|---|---|---|---|---
|  |  | (km s-1) | (km s-1) | (km s-1) | (km s-1) |
HD 61859 | 2011 Oct 06 | 55840.9727 | $-41.92$ | 0.52 | $20.58$ | 0.26 | Fairborn
HD 61859 | 2011 Oct 15 | 55849.9297 | $18.28$ | 0.52 | $-46.32$ | 0.26 | Fairborn
HD 61859 | 2011 Nov 23 | 55888.7539 | $24.98$ | 0.52 | $-55.02$ | 0.26 | Fairborn
HD 61859 | 2012 Jan 01 | 55927.7266 | $-47.12$ | 0.52 | $26.38$ | 0.26 | Fairborn
HD 61859 | 2012 Jan 18 | 55944.8945 | $21.68$ | 0.52 | $-50.92$ | 0.26 | Fairborn
HD 61859 | 2012 Feb 25 | 55982.8242 | $29.28$ | 0.52 | $-59.92$ | 0.26 | Fairborn
HD 61859 | 2012 Apr 04 | 56021.6875 | $-45.62$ | 0.52 | $23.78$ | 0.26 | Fairborn
HD 61859 | 2012 May 13 | 56060.6953 | $-44.72$ | 0.52 | $23.58$ | 0.26 | Fairborn
HD 61859 | 2012 Oct 16 | 56216.8750 | $-48.32$ | 0.52 | $28.58$ | 0.26 | Fairborn
HD 61859 | 2012 Nov 04 | 56235.8281 | $19.58$ | 0.52 | $-47.82$ | 0.26 | Fairborn
HD 61859 | 2012 Dec 17 | 56278.7109 | $-51.42$ | 0.52 | $30.68$ | 0.26 | Fairborn
HD 61859 | 2013 Jan 05 | 56297.9297 | $28.18$ | 0.52 | $-58.92$ | 0.26 | Fairborn
HD 61859 | 2013 Jan 16 | 56308.9297 | $-52.02$ | 0.52 | $32.48$ | 0.26 | Fairborn
HD 61859 | 2013 Feb 01 | 56324.9414 | $35.28$ | 0.52 | $-66.92$ | 0.26 | Fairborn
HD 61859 | 2013 Feb 17 | 56340.8398 | $-51.72$ | 0.52 | $32.18$ | 0.26 | Fairborn
HD 61859 | 2013 Mar 24 | 56375.8242 | $-45.12$ | 0.52 | $23.18$ | 0.26 | Fairborn
HD 61859 | 2013 Sep 21 | 56557.0156 | $-44.82$ | 0.52 | $23.38$ | 0.26 | Fairborn
HD 61859 | 2013 Oct 11 | 56576.9414 | $36.18$ | 0.52 | $-66.42$ | 0.26 | Fairborn
HD 61859 | 2013 Nov 26 | 56622.8594 | $-51.42$ | 0.52 | $32.28$ | 0.26 | Fairborn
HD 61859 | 2013 Dec 16 | 56642.9688 | $39.18$ | 0.52 | $-70.42$ | 0.26 | Fairborn
HD 61859 | 2014 Jan 01 | 56659.0195 | $-45.12$ | 0.52 | $24.48$ | 0.26 | Fairborn
HD 61859 | 2014 Jan 17 | 56674.9531 | $36.18$ | 0.52 | $-67.62$ | 0.26 | Fairborn
HD 61859 | 2014 Mar 17 | 56733.8281 | $31.18$ | 0.52 | $-62.52$ | 0.26 | Fairborn
HD 61859 | 2014 Oct 28 | 56958.9648 | $32.78$ | 0.52 | $-63.02$ | 0.26 | Fairborn
HD 61859 | 2014 Dec 30 | 57021.9961 | $33.08$ | 0.52 | $-63.02$ | 0.26 | Fairborn
HD 61859 | 2015 Feb 06 | 57059.9023 | $-37.52$ | 0.52 | $15.68$ | 0.26 | Fairborn
HD 61859 | 2015 Oct 03 | 57298.9531 | $18.88$ | 0.52 | $-46.62$ | 0.26 | Fairborn
HD 61859 | 2015 Nov 21 | 57347.8672 | $-52.42$ | 0.52 | $32.68$ | 0.26 | Fairborn
HD 61859 | 2016 Jan 26 | 57413.6484 | $-48.41$ | 0.49 | $28.79$ | 0.34 | APO
HD 61859 | 2016 Feb 11 | 57429.8359 | $40.78$ | 0.52 | $-73.32$ | 0.26 | Fairborn
HD 61859 | 2016 Mar 15 | 57462.8203 | $33.78$ | 0.52 | $-65.42$ | 0.26 | Fairborn
HD 61859 | 2016 Apr 14 | 57492.7852 | $41.18$ | 0.52 | $-73.32$ | 0.26 | Fairborn
HD 61859 | 2016 May 10 | 57518.6641 | $12.28$ | 0.52 | $-39.42$ | 0.26 | Fairborn
HD 61859 | 2016 Sep 16 | 57648.0078 | $36.18$ | 0.52 | $-67.12$ | 0.26 | Fairborn
HD 61859 | 2016 Oct 16 | 57678.0000 | $26.18$ | 0.52 | $-55.72$ | 0.26 | Fairborn
HD 61859 | 2017 Jan 26 | 57779.8008 | $13.48$ | 0.52 | $-40.82$ | 0.26 | Fairborn
HD 61859 | 2017 Mar 09 | 57821.7266 | $-51.07$ | 0.47 | $31.64$ | 0.34 | APO
HD 61859 | 2017 Mar 13 | 57825.7891 | $-41.22$ | 0.52 | $18.28$ | 0.26 | Fairborn
HD 61859 | 2017 Apr 04 | 57847.6133 | $-38.00$ | 0.46 | $17.10$ | 0.33 | APO
HD 61859 | 2017 Apr 13 | 57856.7305 | $-42.32$ | 0.52 | $21.28$ | 0.26 | Fairborn
HD 61859 | 2017 May 27 | 57900.6562 | $39.48$ | 0.52 | $-70.92$ | 0.26 | Fairborn
HD 61859 | 2017 Sep 18 | 58014.9219 | $-40.72$ | 0.52 | $18.18$ | 0.26 | Fairborn
HD 61859 | 2017 Oct 30 | 58056.8828 | $31.88$ | 0.52 | $-62.92$ | 0.26 | Fairborn
HD 61859 | 2017 Dec 02 | 58089.8438 | $38.59$ | 0.48 | $-71.43$ | 0.34 | APO
HD 61859 | 2017 Dec 12 | 58099.8633 | $-40.52$ | 0.52 | $19.08$ | 0.26 | Fairborn
HD 61859 | 2018 Jan 04 | 58122.6953 | $40.39$ | 0.49 | $-72.88$ | 0.35 | APO
HD 61859 | 2018 Mar 19 | 58196.8555 | $-51.12$ | 0.52 | $30.08$ | 0.26 | Fairborn
HD 61859 | 2018 Apr 04 | 58212.7109 | $18.65$ | 0.45 | $-49.94$ | 0.32 | APO
HD 61859 | 2018 May 13 | 58251.7070 | $19.78$ | 0.52 | $-49.82$ | 0.26 | Fairborn
HD 61859 | 2018 Oct 29 | 58420.9922 | $-50.82$ | 0.52 | $30.48$ | 0.26 | Fairborn
HD 61859 | 2018 Nov 16 | 58438.7891 | $36.05$ | 0.47 | $-69.16$ | 0.34 | APO
HD 61859 | 2018 Dec 24 | 58476.8945 | $-34.22$ | 0.52 | $11.18$ | 0.26 | Fairborn
HD 61859 | 2019 Jan 14 | 58497.6406 | $29.80$ | 0.48 | $-61.33$ | 0.35 | APO
HD 61859 | 2019 Jan 15 | 58498.7422 | $36.86$ | 1.00 | $-67.55$ | 0.72 | APO
HD 61859 | 2019 Jan 19 | 58502.8945 | $28.35$ | 0.44 | $-58.67$ | 0.31 | APO
HD 61859 | 2019 Jan 31 | 58514.9023 | $-51.08$ | 0.48 | $30.98$ | 0.34 | APO
HD 61859 | 2019 Feb 25 | 58539.8281 | $-33.82$ | 0.52 | $10.18$ | 0.26 | Fairborn
HD 61859 | 2019 Mar 24 | 58566.6914 | $19.95$ | 0.44 | $-49.33$ | 0.32 | APO
HD 61859 | 2019 Oct 14 | 58770.9414 | $-39.27$ | 0.48 | $17.66$ | 0.35 | APO
HD 61859 | 2019 Nov 13 | 58800.8242 | $-46.72$ | 0.52 | $25.08$ | 0.26 | Fairborn
HD 61859 | 2019 Nov 14 | 58801.8203 | $-43.22$ | 0.52 | $20.88$ | 0.26 | Fairborn
HD 61859 | 2019 Nov 14 | 58802.0078 | $-40.39$ | 0.47 | $20.32$ | 0.34 | APO
HD 61859 | 2020 Jan 12 | 58860.7578 | $-50.79$ | 0.46 | $32.45$ | 0.32 | APO
HD 61859 | 2020 Jan 12 | 58860.7891 | $-52.12$ | 0.52 | $32.08$ | 0.26 | Fairborn
HD 61859 | 2020 Jan 27 | 58875.6953 | $30.88$ | 0.52 | $-61.62$ | 0.26 | Fairborn
HD 61859 | 2020 Jan 28 | 58876.7081 | $37.08$ | 0.52 | $-68.22$ | 0.26 | Fairborn
HD 61859 | 2020 Jan 29 | 58877.7080 | $41.58$ | 0.52 | $-72.62$ | 0.26 | Fairborn
HD 61859 | 2020 Jan 31 | 58879.7079 | $37.98$ | 0.52 | $-69.22$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 01 | 58880.7079 | $30.08$ | 0.52 | $-61.42$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 02 | 58881.7079 | $20.68$ | 0.52 | $-49.32$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 07 | 58886.7077 | $-36.22$ | 0.52 | $13.48$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 08 | 58887.7077 | $-42.52$ | 0.52 | $21.18$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 09 | 58888.7076 | $-47.02$ | 0.52 | $26.28$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 14 | 58893.7074 | $-49.92$ | 0.52 | $29.98$ | 0.26 | Fairborn
HD 61859 | 2020 Feb 14 | 58893.7539 | $-49.11$ | 0.46 | $29.98$ | 0.32 | APO
HD 89822 | 2005 Feb 09 | 53410.8867 | $12.20$ | 0.22 | $-25.17$ | 0.49 | Fairborn
HD 89822 | 2005 Apr 01 | 53461.8945 | $-21.91$ | 0.22 | $29.61$ | 0.49 | Fairborn
HD 89822 | 2005 Apr 16 | 53476.8242 | $22.87$ | 0.22 | $-43.30$ | 0.49 | Fairborn
HD 89822 | 2005 May 05 | 53495.9180 | $-39.67$ | 0.22 | $60.16$ | 0.49 | Fairborn
HD 89822 | 2005 May 21 | 53511.8711 | $23.34$ | 0.22 | $-43.76$ | 0.49 | Fairborn
HD 89822 | 2006 Jan 31 | 53766.8867 | $24.40$ | 0.22 | $-46.04$ | 0.49 | Fairborn
HD 89822 | 2006 Apr 17 | 53842.8672 | $-48.70$ | 0.22 | $73.82$ | 0.49 | Fairborn
HD 89822 | 2006 May 14 | 53869.8242 | $19.00$ | 0.22 | $-36.81$ | 0.49 | Fairborn
HD 89822 | 2006 May 30 | 53885.7500 | $10.52$ | 0.22 | $-21.62$ | 0.49 | Fairborn
HD 89822 | 2017 Jan 11 | 57764.8320 | $9.09$ | 0.53 | $-20.18$ | 1.54 | APO
HD 89822 | 2017 Feb 16 | 57800.8867 | $-16.10$ | 0.51 | $22.17$ | 1.56 | APO
HD 89822 | 2017 Mar 09 | 57821.7422 | $18.95$ | 0.55 | $-36.05$ | 1.64 | APO
HD 89822 | 2017 Apr 04 | 57847.6406 | $-28.27$ | 0.54 | $40.76$ | 1.62 | APO
HD 89822 | 2017 Apr 10 | 57853.6602 | $22.15$ | 0.71 | $-41.97$ | 2.13 | APO
HD 89822 | 2017 Dec 27 | 58114.7695 | $-47.77$ | 0.68 | $73.27$ | 2.00 | APO
HD 89822 | 2018 Jan 04 | 58122.7500 | $18.62$ | 0.55 | $-37.10$ | 1.61 | APO
HD 89822 | 2018 Jan 28 | 58146.9023 | $9.31$ | 0.50 | $-21.46$ | 1.47 | APO
HD 89822 | 2018 Apr 04 | 58212.7305 | $22.88$ | 0.53 | $-42.29$ | 1.56 | APO
HD 89822 | 2019 Jan 19 | 58502.9492 | $24.84$ | 0.50 | $-44.53$ | 1.48 | APO
HD 89822 | 2019 Jan 22 | 58505.7930 | $9.71$ | 0.53 | $-23.13$ | 1.57 | APO
HD 89822 | 2019 Jan 31 | 58514.9141 | $24.61$ | 0.52 | $-44.97$ | 1.51 | APO
HD 89822 | 2019 Feb 17 | 58531.6211 | $-48.14$ | 0.57 | $72.88$ | 1.66 | APO
HD 89822 | 2019 Mar 24 | 58566.7266 | $-51.54$ | 0.56 | $78.12$ | 1.66 | APO
HD 89822 | 2019 Apr 21 | 58594.8203 | $22.62$ | 0.22 | $-43.11$ | 0.49 | Fairborn
HD 89822 | 2019 Apr 26 | 58599.9062 | $-18.51$ | 0.22 | $24.87$ | 0.49 | Fairborn
HD 89822 | 2019 Apr 27 | 58600.7969 | $-42.11$ | 0.22 | $62.64$ | 0.49 | Fairborn
HD 89822 | 2019 May 02 | 58605.8711 | $20.06$ | 0.22 | $-38.11$ | 0.49 | Fairborn
HD 89822 | 2019 May 04 | 58607.7891 | $24.41$ | 0.22 | $-45.97$ | 0.49 | Fairborn
HD 89822 | 2019 May 18 | 58621.6367 | $9.95$ | 0.22 | $-20.78$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 05 | 58639.7500 | $13.34$ | 0.22 | $-27.28$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 19 | 58653.8320 | $24.66$ | 0.22 | $-45.41$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 20 | 58654.7461 | $22.74$ | 0.22 | $-43.04$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 21 | 58655.7578 | $16.49$ | 0.22 | $-32.00$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 23 | 58657.7148 | $-15.73$ | 0.22 | $20.75$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 24 | 58658.7422 | $-43.53$ | 0.22 | $64.73$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 25 | 58659.7188 | $-49.77$ | 0.22 | $75.39$ | 0.49 | Fairborn
HD 89822 | 2019 Jun 26 | 58660.6758 | $-27.83$ | 0.22 | $39.81$ | 0.49 | Fairborn
HD 89822 | 2019 Sep 19 | 58745.9727 | $24.25$ | 0.22 | $-45.99$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 05 | 58761.9141 | $-15.83$ | 0.22 | $19.91$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 06 | 58762.9219 | $-42.92$ | 0.22 | $63.11$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 07 | 58763.9375 | $-49.41$ | 0.22 | $73.76$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 08 | 58764.9336 | $-27.03$ | 0.22 | $38.61$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 14 | 58770.9844 | $19.99$ | 0.59 | $-39.24$ | 1.79 | APO
HD 89822 | 2019 Oct 19 | 58776.0352 | $-39.42$ | 0.22 | $58.53$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 20 | 58776.9180 | $-16.82$ | 0.22 | $21.10$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 24 | 58781.0391 | $24.53$ | 0.22 | $-46.57$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 25 | 58782.0391 | $23.18$ | 0.22 | $-44.21$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 26 | 58782.8672 | $18.71$ | 0.22 | $-35.75$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 30 | 58786.8555 | $-51.43$ | 0.22 | $77.33$ | 0.49 | Fairborn
HD 89822 | 2019 Oct 31 | 58787.7812 | $-35.30$ | 0.22 | $51.06$ | 0.49 | Fairborn
HD 89822 | 2019 Nov 14 | 58802.0273 | $14.94$ | 0.54 | $-29.78$ | 1.57 | APO
HD 89822 | 2019 Nov 23 | 58810.8086 | $-38.71$ | 0.22 | $56.24$ | 0.49 | Fairborn
HD 89822 | 2019 Dec 17 | 58834.7422 | $-18.47$ | 0.22 | $23.21$ | 0.49 | Fairborn
HD 89822 | 2019 Dec 20 | 58837.7500 | $22.06$ | 0.22 | $-42.07$ | 0.49 | Fairborn
HD 89822 | 2019 Dec 21 | 58838.7891 | $24.70$ | 0.22 | $-46.26$ | 0.49 | Fairborn
HD 89822 | 2020 Jan 08 | 58856.7891 | $-46.02$ | 0.22 | $68.84$ | 0.49 | Fairborn
HD 89822 | 2020 Jan 12 | 58860.7734 | $20.97$ | 0.53 | $-39.66$ | 1.63 | APO
HD 89822 | 2020 Jan 18 | 58866.9258 | $-37.62$ | 0.22 | $55.50$ | 0.49 | Fairborn
HD 89822 | 2020 Jan 19 | 58867.9258 | $-51.66$ | 0.22 | $77.62$ | 0.49 | Fairborn
HD 89822 | 2020 Jan 31 | 58879.6992 | $-49.89$ | 0.22 | $75.10$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 08 | 58887.6992 | $12.78$ | 0.22 | $-26.24$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 15 | 58894.8906 | $16.63$ | 0.22 | $-33.77$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 16 | 58895.6484 | $21.51$ | 0.22 | $-41.46$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 17 | 58896.6367 | $24.57$ | 0.22 | $-46.32$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 18 | 58897.6406 | $23.60$ | 0.22 | $-44.93$ | 0.49 | Fairborn
HD 89822 | 2020 Feb 19 | 58898.8320 | $17.00$ | 0.22 | $-33.39$ | 0.49 | Fairborn
HD 109510 | 2017 Feb 16 | 57800.9109 | $54.17$ | 0.43 | $-55.91$ | 1.19 | APO
HD 109510 | 2017 Mar 09 | 57821.7621 | $78.15$ | 0.46 | $-85.41$ | 1.26 | APO
HD 109510 | 2017 Dec 02 | 58089.9622 | $-46.53$ | 0.48 | $62.37$ | 1.31 | APO
HD 109510 | 2018 May 10 | 58248.5463 | $49.63$ | 0.15 | $-51.71$ | 1.09 | CTIO
HD 109510 | 2019 Jan 13 | 58496.8454 | $80.35$ | 0.18 | $-88.34$ | 0.53 | CTIO
HD 109510 | 2019 Jan 16 | 58499.8734 | $-22.54$ | 0.17 | $34.88$ | 0.49 | CTIO
HD 109510 | 2019 Jan 17 | 58500.8871 | $-47.58$ | 0.18 | $63.47$ | 0.51 | CTIO
HD 109510 | 2019 Jan 28 | 58511.8517 | $78.76$ | 0.19 | $-86.67$ | 0.54 | CTIO
HD 109510 | 2019 Jan 29 | 58512.8259 | $42.81$ | 0.19 | $-43.54$ | 0.56 | CTIO
HD 109510 | 2019 Jan 31 | 58514.9867 | $-34.64$ | 0.45 | $49.45$ | 1.18 | APO
HD 109510 | 2019 Feb 12 | 58526.8152 | $70.69$ | 0.20 | $-76.22$ | 0.56 | CTIO
HD 109510 | 2019 Feb 13 | 58527.8282 | $28.73$ | 0.18 | $-26.07$ | 0.50 | CTIO
HD 109510 | 2019 Feb 15 | 58529.8156 | $-38.68$ | 0.18 | $53.55$ | 0.49 | CTIO
HD 109510 | 2019 Feb 16 | 58530.8338 | $-54.88$ | 0.18 | $72.77$ | 0.53 | CTIO
HD 109510 | 2019 Feb 17 | 58531.7947 | $-40.67$ | 0.18 | $55.52$ | 0.51 | CTIO
HD 109510 | 2019 Feb 18 | 58532.8140 | $39.66$ | 0.17 | $-39.42$ | 0.51 | CTIO
HD 109510 | 2019 Feb 24 | 58538.8251 | $-50.32$ | 0.19 | $67.04$ | 0.55 | CTIO
HD 109510 | 2019 Feb 26 | 58540.7412 | $77.76$ | 0.19 | $-85.32$ | 0.53 | CTIO
HD 109510 | 2019 Feb 27 | 58541.7464 | $60.88$ | 0.18 | $-64.90$ | 0.52 | CTIO
HD 109510 | 2019 Mar 05 | 58547.7628 | $62.38$ | 0.17 | $-66.44$ | 0.48 | CTIO
HD 109510 | 2019 Mar 21 | 58563.7068 | $62.93$ | 0.10 | $-66.97$ | 0.77 | CTIO
HD 109510 | 2019 Mar 21 | 58563.7323 | $62.15$ | 0.17 | $-66.21$ | 0.49 | CTIO
HD 109510 | 2019 Mar 24 | 58566.7556 | $-44.78$ | 0.46 | $60.14$ | 1.25 | APO
HD 109510 | 2019 Mar 27 | 58569.7259 | $58.93$ | 0.18 | $-62.56$ | 0.49 | CTIO
HD 109510 | 2019 Nov 14 | 58802.0294 | $-52.61$ | 0.48 | $69.84$ | 1.30 | APO
HD 109510 | 2020 Jan 07 | 58855.8570 | $59.03$ | 0.19 | $-62.26$ | 0.53 | CTIO
HD 109510 | 2020 Jan 08 | 58856.8712 | $73.88$ | 0.20 | $-79.82$ | 0.56 | CTIO
HD 109510 | 2020 Jan 14 | 58862.8429 | $28.21$ | 0.18 | $-25.05$ | 0.50 | CTIO
HD 109510 | 2020 Jan 15 | 58863.8831 | $80.80$ | 0.18 | $-88.49$ | 0.52 | CTIO
HD 109510 | 2020 Jan 16 | 58864.8731 | $47.75$ | 0.18 | $-49.18$ | 0.52 | CTIO
HD 109510 | 2020 Jan 19 | 58867.8896 | $-50.26$ | 0.42 | $66.74$ | 1.25 | CTIO
HD 109510 | 2020 Jan 20 | 58868.8921 | $-51.79$ | 0.20 | $68.98$ | 0.59 | CTIO
HD 109510 | 2020 Jan 23 | 58871.8459 | $63.04$ | 0.20 | $-66.87$ | 0.54 | CTIO
HD 109510 | 2020 Jan 26 | 58874.8406 | $-43.16$ | 0.44 | $59.32$ | 1.25 | CTIO
HD 109510 | 2020 Jan 28 | 58876.8490 | $-28.61$ | 0.22 | $42.62$ | 0.64 | CTIO
HD 109510 | 2020 Jan 29 | 58877.8545 | $58.01$ | 0.55 | $-61.83$ | 1.60 | CTIO
HD 109510 | 2020 Jan 31 | 58879.8639 | $34.24$ | 0.19 | $-32.34$ | 0.54 | CTIO
HD 109510 | 2020 Feb 14 | 58893.7607 | $65.90$ | 0.47 | $-71.83$ | 1.27 | APO
HD 109510 | 2020 Feb 25 | 58904.8786 | $-53.80$ | 0.25 | $72.06$ | 0.28 | Fairborn
HD 109510 | 2020 May 07 | 58976.8105 | $-24.13$ | 0.25 | $36.26$ | 0.28 | Fairborn
HD 109510 | 2020 Dec 21 | 59204.8936 | $-40.80$ | 0.25 | $57.10$ | 0.28 | Fairborn
HD 109510 | 2021 Jan 04 | 59218.8653 | $-22.15$ | 0.25 | $34.62$ | 0.28 | Fairborn
HD 109510 | 2021 Jan 14 | 59228.8270 | $-38.18$ | 0.25 | $53.64$ | 0.28 | Fairborn
HD 109510 | 2021 Feb 06 | 59251.9700 | $53.97$ | 0.25 | $-56.89$ | 0.28 | Fairborn
HD 109510 | 2021 Feb 23 | 59268.7125 | $33.74$ | 0.25 | $-32.85$ | 0.28 | Fairborn
HD 109510 | 2021 Mar 15 | 59288.9302 | $72.45$ | 0.25 | $-78.32$ | 0.28 | Fairborn
HD 109510 | 2021 Mar 20 | 59293.9990 | $-55.02$ | 0.25 | $73.54$ | 0.28 | Fairborn
HD 109510 | 2021 Mar 31 | 59304.8677 | $56.47$ | 0.25 | $-60.25$ | 0.28 | Fairborn
HD 109510 | 2021 Apr 10 | 59314.9131 | $-40.57$ | 0.25 | $56.27$ | 0.28 | Fairborn
HD 109510 | 2021 Apr 18 | 59322.8794 | $-51.72$ | 0.25 | $69.37$ | 0.28 | Fairborn
HD 109510 | 2021 Apr 30 | 59334.8455 | $29.79$ | 0.25 | $-27.46$ | 0.28 | Fairborn
HD 109510 | 2021 May 04 | 59338.6809 | $-45.86$ | 0.25 | $62.51$ | 0.28 | Fairborn
HD 109510 | 2021 May 05 | 59339.6808 | $23.70$ | 0.25 | $-19.79$ | 0.28 | Fairborn
HD 109510 | 2021 May 06 | 59340.6808 | $81.24$ | 0.25 | $-89.27$ | 0.28 | Fairborn
HD 109510 | 2021 May 07 | 59341.6807 | $51.46$ | 0.25 | $-53.23$ | 0.28 | Fairborn
HD 109510 | 2021 May 09 | 59343.6806 | $-25.46$ | 0.25 | $37.79$ | 0.28 | Fairborn
HD 109510 | 2021 May 10 | 59344.6804 | $-48.69$ | 0.25 | $65.92$ | 0.28 | Fairborn
HD 109510 | 2021 May 11 | 59345.6804 | $-53.12$ | 0.25 | $71.12$ | 0.28 | Fairborn
HD 109510 | 2021 May 13 | 59347.6803 | $74.44$ | 0.25 | $-81.92$ | 0.28 | Fairborn
HD 109510 | 2021 May 14 | 59348.6802 | $65.22$ | 0.25 | $-69.70$ | 0.28 | Fairborn
HD 109510 | 2021 May 15 | 59349.6801 | $22.51$ | 0.25 | $-19.40$ | 0.28 | Fairborn
HD 109510 | 2021 May 16 | 59350.6800 | $-14.75$ | 0.25 | $25.09$ | 0.28 | Fairborn
HD 109510 | 2021 May 17 | 59351.6800 | $-42.78$ | 0.25 | $57.94$ | 0.28 | Fairborn
HD 109510 | 2021 May 18 | 59352.6799 | $-55.24$ | 0.25 | $73.34$ | 0.28 | Fairborn
HD 109510 | 2021 May 19 | 59353.6798 | $-31.78$ | 0.25 | $45.14$ | 0.28 | Fairborn
HD 109510 | 2021 May 24 | 59358.6794 | $-34.06$ | 0.25 | $48.42$ | 0.28 | Fairborn
HD 109510 | 2021 May 25 | 59359.6793 | $-53.45$ | 0.25 | $71.30$ | 0.28 | Fairborn
HD 109510 | 2021 May 26 | 59360.6793 | $-46.53$ | 0.25 | $62.81$ | 0.28 | Fairborn
HD 109510 | 2021 May 28 | 59362.6791 | $81.34$ | 0.25 | $-89.00$ | 0.28 | Fairborn
HD 109510 | 2021 May 29 | 59363.6790 | $51.51$ | 0.25 | $-54.07$ | 0.28 | Fairborn
HD 191692 | 2004 Mar 27 | 53091.9720 | $29.60$ | 0.89 | $-101.50$ | 1.79 | Fairborn
HD 191692 | 2004 Oct 05 | 53283.7036 | $-47.10$ | 1.34 | $-0.70$ | 2.68 | Fairborn
HD 191692 | 2004 Oct 18 | 53296.6486 | $4.80$ | 0.89 | $-74.40$ | 1.79 | Fairborn
HD 191692 | 2004 Oct 24 | 53302.7319 | $-53.60$ | 1.34 | $3.70$ | 2.68 | Fairborn
HD 191692 | 2004 Oct 25 | 53303.6305 | $-53.70$ | 1.34 | $3.70$ | 2.68 | Fairborn
HD 191692 | 2004 Nov 05 | 53314.6562 | $28.80$ | 0.89 | $-101.90$ | 1.79 | Fairborn
HD 191692 | 2004 Nov 11 | 53320.6595 | $-52.60$ | 1.34 | $4.50$ | 2.68 | Fairborn
HD 191692 | 2014 Jul 03 | 56841.8663 | $17.37$ | 0.24 | $-90.68$ | 0.36 | CTIO
HD 191692 | 2019 Jun 06 | 58640.8262 | $43.15$ | 0.32 | $-123.37$ | 0.46 | CTIO
HD 191692 | 2019 Aug 12 | 58707.6604 | $0.24$ | 0.25 | $-68.29$ | 0.38 | CTIO
HD 191692 | 2019 Aug 13 | 58708.6722 | $25.08$ | 0.30 | $-100.51$ | 0.45 | CTIO
HD 191692 | 2019 Aug 14 | 58709.6792 | $39.63$ | 0.36 | $-119.35$ | 0.51 | CTIO
HD 191692 | 2019 Aug 17 | 58712.6434 | $-51.92$ | 0.45 | $0.28$ | 0.60 | CTIO
HD 191692 | 2019 Aug 29 | 58724.6105 | $-2.38$ | 0.25 | $-64.37$ | 0.37 | CTIO
HD 191692 | 2019 Aug 30 | 58725.6912 | $21.91$ | 0.28 | $-96.19$ | 0.41 | CTIO
HD 191692 | 2019 Aug 31 | 58726.5889 | $43.76$ | 0.27 | $-124.37$ | 0.39 | CTIO
HD 191692 | 2019 Sep 03 | 58729.6022 | $-50.62$ | 0.42 | $-0.36$ | 0.54 | CTIO
HD 191692 | 2019 Sep 04 | 58730.5631 | $-53.58$ | 0.42 | $2.39$ | 0.57 | CTIO
HD 191692 | 2019 Sep 05 | 58731.5943 | $-53.72$ | 0.46 | $2.28$ | 0.63 | CTIO
HD 191692 | 2019 Sep 15 | 58741.5586 | $-5.50$ | 0.27 | $-60.96$ | 0.37 | CTIO
HD 191692 | 2019 Sep 16 | 58742.5689 | $14.65$ | 0.26 | $-87.40$ | 0.38 | CTIO
HD 191692 | 2019 Sep 17 | 58743.5649 | $42.85$ | 0.33 | $-123.43$ | 0.47 | CTIO
HD 191692 | 2019 Oct 05 | 58761.6219 | $3.61$ | 0.28 | $-72.76$ | 0.41 | CTIO
HD 191692 | 2019 Oct 10 | 58766.5178 | $-52.65$ | 0.45 | $0.97$ | 0.62 | CTIO
HD 191692 | 2019 Oct 10 | 58766.6965 | $-54.20$ | 1.34 | $-1.20$ | 2.68 | Fairborn
HD 191692 | 2019 Oct 10 | 58767.4814 | $-50.46$ | 0.61 | $-0.37$ | 0.78 | CTIO
HD 191692 | 2019 Oct 11 | 58767.5990 | $-52.20$ | 1.34 | $-0.60$ | 2.68 | Fairborn
HD 191692 | 2019 Oct 19 | 58775.6700 | $-6.00$ | 0.89 | $-57.60$ | 1.79 | Fairborn
HD 191692 | 2019 Oct 20 | 58776.5546 | $8.29$ | 0.47 | $-79.32$ | 0.70 | CTIO
HD 191692 | 2019 Oct 20 | 58776.6822 | $12.50$ | 0.89 | $-82.40$ | 1.79 | Fairborn
HD 191692 | 2019 Oct 21 | 58777.5640 | $37.04$ | 0.32 | $-116.10$ | 0.47 | CTIO
HD 191692 | 2019 Oct 21 | 58777.6927 | $39.70$ | 0.89 | $-121.60$ | 1.79 | Fairborn
HD 191692 | 2019 Oct 22 | 58778.5228 | $19.41$ | 0.31 | $-92.89$ | 0.44 | CTIO
HD 191692 | 2019 Oct 22 | 58778.6162 | $11.90$ | 0.89 | $-83.00$ | 1.79 | Fairborn
HD 191692 | 2019 Oct 25 | 58781.5327 | $-52.55$ | 0.44 | $1.49$ | 0.60 | CTIO
HD 191692 | 2019 Oct 26 | 58782.6390 | $-54.40$ | 1.34 | $1.70$ | 2.68 | Fairborn
HD 191692 | 2019 Oct 27 | 58783.6384 | $-53.70$ | 1.34 | $2.50$ | 2.68 | Fairborn
HD 191692 | 2019 Nov 06 | 58793.5064 | $4.57$ | 0.29 | $-74.38$ | 0.44 | CTIO
HD 191692 | 2019 Nov 07 | 58795.4940 | $29.78$ | 0.31 | $-106.24$ | 0.45 | CTIO
HD 191692 | 2020 Sep 11 | 59103.6197 | $36.50$ | 0.89 | $-115.20$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 16 | 59108.6166 | $-56.10$ | 1.34 | $4.50$ | 2.68 | Fairborn
HD 191692 | 2020 Sep 17 | 59109.6126 | $-52.20$ | 1.34 | $2.70$ | 2.68 | Fairborn
HD 191692 | 2020 Sep 25 | 59117.6385 | $-13.30$ | 0.89 | $-50.00$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 26 | 59118.6016 | $1.50$ | 0.89 | $-67.30$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 27 | 59119.6038 | $25.20$ | 0.89 | $-95.50$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 28 | 59120.6023 | $41.70$ | 0.89 | $-125.10$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 29 | 59121.6015 | $-17.60$ | 0.89 | $-44.60$ | 1.79 | Fairborn
HD 191692 | 2020 Sep 30 | 59122.6014 | $-44.50$ | 1.34 | $-8.00$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 01 | 59123.6002 | $-53.10$ | 1.34 | $-0.20$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 02 | 59124.5996 | $-54.30$ | 1.34 | $3.60$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 03 | 59125.5985 | $-54.80$ | 1.34 | $3.10$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 04 | 59126.5986 | $-53.50$ | 1.34 | $2.10$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 05 | 59127.5947 | $-50.10$ | 1.34 | $-1.20$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 06 | 59128.5935 | $-47.90$ | 1.34 | $-4.30$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 13 | 59135.6121 | $-1.70$ | 0.89 | $-64.30$ | 1.79 | Fairborn
HD 191692 | 2020 Oct 14 | 59136.5880 | $19.80$ | 0.89 | $-90.60$ | 1.79 | Fairborn
HD 191692 | 2020 Oct 15 | 59137.5874 | $44.40$ | 0.89 | $-127.00$ | 1.79 | Fairborn
HD 191692 | 2020 Oct 16 | 59138.5866 | $-9.80$ | 0.89 | $-52.00$ | 1.79 | Fairborn
HD 191692 | 2020 Oct 18 | 59140.5850 | $-52.90$ | 1.34 | $0.80$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 19 | 59141.5841 | $-52.90$ | 1.34 | $3.40$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 20 | 59142.6096 | $-53.10$ | 1.34 | $3.40$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 21 | 59143.6136 | $-53.60$ | 1.34 | $2.30$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 22 | 59144.6130 | $-50.60$ | 1.34 | $-1.00$ | 2.68 | Fairborn
HD 191692 | 2020 Oct 30 | 59152.6153 | $-2.70$ | 0.89 | $-61.10$ | 1.79 | Fairborn
HD 191692 | 2020 Oct 31 | 59153.6148 | $17.40$ | 0.89 | $-88.10$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 01 | 59154.6248 | $44.20$ | 0.89 | $-125.90$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 02 | 59155.6256 | $-4.50$ | 0.89 | $-58.50$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 04 | 59157.6228 | $-52.50$ | 1.34 | $0.50$ | 2.68 | Fairborn
HD 191692 | 2020 Nov 05 | 59158.6216 | $-53.80$ | 1.34 | $3.10$ | 2.68 | Fairborn
HD 191692 | 2020 Nov 17 | 59170.6104 | $13.40$ | 0.89 | $-83.00$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 18 | 59171.6560 | $43.50$ | 0.89 | $-127.20$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 19 | 59172.6341 | $4.00$ | 0.89 | $-69.90$ | 1.79 | Fairborn
HD 191692 | 2020 Nov 21 | 59174.6069 | $-51.50$ | 1.34 | $-1.90$ | 2.68 | Fairborn
HD 191692 | 2020 Nov 22 | 59175.6065 | $-54.00$ | 1.34 | $5.20$ | 2.68 | Fairborn
HD 191692 | 2020 Nov 25 | 59178.6170 | $-51.50$ | 1.34 | $0.70$ | 2.68 | Fairborn
HD 191692 | 2021 Feb 12 | 59258.0383 | $17.70$ | 0.89 | $-92.90$ | 1.79 | Fairborn
HD 191692 | 2021 Feb 28 | 59274.0231 | $32.70$ | 0.89 | $-109.50$ | 1.79 | Fairborn
HD 191692 | 2021 Mar 01 | 59275.0178 | $26.70$ | 0.89 | $-102.80$ | 1.79 | Fairborn
HD 191692 | 2021 Apr 09 | 59314.0086 | $-54.40$ | 1.34 | $2.40$ | 2.68 | Fairborn
HD 191692 | 2021 Apr 20 | 59324.8890 | $18.10$ | 0.89 | $-90.00$ | 1.79 | Fairborn
HD 191692 | 2021 Apr 24 | 59328.8698 | $-52.20$ | 1.34 | $0.20$ | 2.68 | Fairborn
HD 191692 | 2021 May 07 | 59341.8248 | $12.30$ | 0.89 | $-82.30$ | 1.79 | Fairborn
HD 191692 | 2021 Jun 01 | 59366.8105 | $-52.70$ | 1.34 | $-1.20$ | 2.68 | Fairborn
Table 6: Calibrator Angular Diameters  Target | Calibrator |  $\theta_{\rm UD}$ (mas) | Wavelength
---|---|---|---
HD 61859 | HD 45391 | $0.329\pm 0.017$ |  $H$-band
HD 61859 | HD 56124 | $0.346\pm 0.008$ |  $K$-band
HD 61859 | HD 59037 | $0.391\pm 0.011$ |  $K$-band
HD 61859 | HD 59747 | $0.348\pm 0.017$ |  $K$-band
HD 61859 | HD 63495 | $0.122\pm 0.006$ |  $K$-band
HD 61859 | HD 67709 | $0.443\pm 0.010$ |  $K$-band
HD 61859 | HD 67827 | $0.387\pm 0.019$ |  $K$-band
HD 61859 | HD 72524 | $0.256\pm 0.013$ |  $H$-band
HD 89822 | HD 84812 | $0.300\pm 0.015$ |  $H$-band
HD 89822 | HD 88983 | $0.313\pm 0.008$ |  $K$-band
HD 89822 | HD 96707 | $0.296\pm 0.007$ |  $K$-band
HD 89822 | HD 98772 | $0.235\pm 0.012$ |  $H$-band
HD 109510 | HD 105086 | $0.319\pm 0.016$ |  $H$-band
HD 109510 | HD 107569 | $0.242\pm 0.006$ |  $K$-band
HD 109510 | HD 111718 | $0.231\pm 0.005$ |  $K$-band
HD 109510 | HD 111893 | $0.263\pm 0.013$ |  $H$-band
HD 191692 | HD 188350 | $0.284\pm 0.008$ |  $K$-band
HD 191692 | HD 191014 | $0.826\pm 0.073$ |  $K$-band
HD 191692 | HD 193329 | $0.831\pm 0.082$ |  $K$-band
HD 191692 | HD 195810 | $0.323\pm 0.029$ |  $K$-band
HD 191692 | HD 185124 | $0.495\pm 0.025$ |  $H$-band
HD 191692 | HD 196870 | $0.661\pm 0.050$ |  $H$-band
Figure 5: Reconstructed spectra of HD 61859 around H$\beta$ (top), the Mg b
triplet (middle), and H$\alpha$ (bottom), for example. The reconstructed
spectra are shown in black, and the best-fit model spectra are overplotted in
green for the primary and blue for the secondary.  Figure 6: Reconstructed
spectra of HD 89822 around the Ca H & K lines (top), the Mg b triplet
(middle), and H$\alpha$ (bottom), for example. The reconstructed spectra are
shown in black, and the best-fit model spectra are overplotted in green for
the primary and blue for the secondary. In the top panel, lines relevant to
HgMn and Am stars are labeled, including Ca K 3934Å, a blend of Ca H 3969Å
with H$\epsilon$ 3970Å, and Hg II 3984Å. The Hg II line is much stronger in
the primary star than in the models as expected for HgMn stars, and the Ca K
line of the secondary component is much weaker than in the models as expected
for metallic line stars.  Figure 7: Reconstructed spectra of HD 109510 around
H$\beta$ (top), the Mg b triplet (middle), and H$\alpha$ (bottom), for
example. The reconstructed spectra are shown in black, and the best-fit model
spectra are overplotted in green for the primary and blue for the secondary.
Figure 8: Reconstructed spectra of HD 191692 around H$\beta$ (top), the Mg b
triplet (middle), and H$\alpha$ (bottom), for example. The reconstructed
spectra are shown in black, and the best-fit model spectra are overplotted in
green for the primary and blue for the secondary.

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