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Spectroscopic Orbits For Late-Type Stars. Ii, Francis C. Fekel, Daryl W. Willmarth, Helmut A. Abt, Dimitri Pourbaix
Spectroscopic Orbits For Late-Type Stars. Ii, Francis C. Fekel, Daryl W. Willmarth, Helmut A. Abt, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
We have determined spectroscopic orbital elements for 13 systems—10 single-lined binaries and three double-lined binaries. For the three binaries with previously published spectroscopic orbits, we have computed improved or comparable elements. While two systems have relatively short periods between 10 and 19 days, the remaining systems have much longer periods ranging from 604 to 9669 days. One of the single-lined systems, HD 142640, shows both short-period and long-period velocity variations and so is triple. For three systems—HD 59380, HD 160933, and HD 161163—we have combined our spectroscopic results with Hipparcos astrometric observations to obtain astrometric orbits. For HD 14802 we …
Precision Orbit Of Δ Delphini And Prospects For Astrometric Detection Of Exoplanets, Tyler Gardner, John D. Monnier, Francis C. Fekel, Michael H. Williamson, Douglas K. Duncan, Timothy R. White, Michael Ireland, Fred C. Adams, Travis Barman, Fabien Baron, Theo A. Ten Brummelaar, Xiao Che, Daniel Huber, Stefan Kraus, Rachael M. Roettenbacher, Gail Schaefer, Judit Sturmann, Laszlo Sturmann, Samuel J. Swihart, Ming Zhao
Precision Orbit Of Δ Delphini And Prospects For Astrometric Detection Of Exoplanets, Tyler Gardner, John D. Monnier, Francis C. Fekel, Michael H. Williamson, Douglas K. Duncan, Timothy R. White, Michael Ireland, Fred C. Adams, Travis Barman, Fabien Baron, Theo A. Ten Brummelaar, Xiao Che, Daniel Huber, Stefan Kraus, Rachael M. Roettenbacher, Gail Schaefer, Judit Sturmann, Laszlo Sturmann, Samuel J. Swihart, Ming Zhao
Information Systems and Engineering Management Research Publications
Combining visual and spectroscopic orbits of binary stars leads to a determination of the full 3D orbit, individual masses, and distance to the system. We present a full analysis of the evolved binary system δ Delphini using astrometric data from the MIRC and PAVO instruments on the CHARA long-baseline interferometer, 97 new spectra from the Fairborn Observatory, and 87 unpublished spectra from the Lick Observatory. We determine the full set of orbital elements for δ Del, along with masses of 1.78 ± 0.07 M⊙ and 1.62 ± 0.07 M⊙ for each component, and a distance of 63.61 ± 0.89 pc. …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. X. Hd 96511, Hr 7578, And Kz Andromedae, Francis C. Fekel, Gregory W. Henry, Jocelyn Tomkin
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. X. Hd 96511, Hr 7578, And Kz Andromedae, Francis C. Fekel, Gregory W. Henry, Jocelyn Tomkin
Information Systems and Engineering Management Research Publications
From an extensive number of newly acquired radial velocities we determine the orbital elements for three late-type dwarf systems, HD 96511, HR 7578, and KZ And. The orbital periods are 18.89737 ± 0.00002, 46.81610 ± 0.00006, and 3.0329113 ± 0.0000005 days, respectively, and all three systems are eccentric, although KZ And is just barely so. We have detected lines of the secondary of HD 96511 for the first time. The orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) of the binary components all have accuracies of 0.2% or better. …
Orbital Elements And Stellar Parameters Of The Active Binary Ux Arietis, Christian A. Hummel, John D. Monnier, Rachael M. Roettenbacher, Guillermo Torres, Gregory W. Henry, Heidi Korhonen, Anthony Beasley, Gail H. Schaefer, Nils H. Turner, Theo A. Ten Brummelaar, Chris D. Farrington, Judit Sturmann, Laszlo Sturmann, Frédérique Baron, Stefan Kraus
Orbital Elements And Stellar Parameters Of The Active Binary Ux Arietis, Christian A. Hummel, John D. Monnier, Rachael M. Roettenbacher, Guillermo Torres, Gregory W. Henry, Heidi Korhonen, Anthony Beasley, Gail H. Schaefer, Nils H. Turner, Theo A. Ten Brummelaar, Chris D. Farrington, Judit Sturmann, Laszlo Sturmann, Frédérique Baron, Stefan Kraus
Information Systems and Engineering Management Research Publications
Stellar activity observed as large surface spots, radio flares, or emission lines is often found in binary systems. UX Arietis exhibits these signs of activity, originating on the K0 subgiant primary component. Our aim is to resolve the binary, measure the orbital motion, and provide accurate stellar parameters such as masses and luminosities to aid in the interpretation of the observed phenomena. Using the CHARA six-telescope optical long-baseline array on Mount Wilson, California, we obtained amplitudes and phases of the interferometric visibility on baselines up to 330 m in length, resolving the two components of the binary. We reanalyzed archival …
Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell
Orbital Solutions And Absolute Elements Of The Massive Algol Binary Et Tauri, Richard M. Williamon, Horace Dale, Charles L. Evavold, Alexander Langoussis, Francis C. Fekel, Matthew W. Muterspaugh, Stephen Williams, Kate Napier, James R. Sowell
Information Systems and Engineering Management Research Publications
We acquired differential UBV photoelectric photometry and radial velocities of the relatively bright, understudied, massive Algol binary ET Tau and utilized the Wilson-Devinney (WD) analysis program to obtain a simultaneous solution of these observations. To improve the orbital ephemeris, the V measurements from the ASAS program were also analyzed. Because of the very rapid rotation of the significantly more massive and hotter component (B2/3 spectral class), only radial velocities of the secondary component, which has a ∼B7 spectral class, could be measured. We derive masses of ${M}_{1}=14.34\pm 0.28\,{M}_{\odot }$ and ${M}_{2}=6.339\pm 0.117\,{M}_{\odot }$ and equal-volume radii of ${R}_{1}=6.356\pm 0.056\,{R}_{\odot }$ …
Spectroscopic Orbits For 15 Late-Type Stars, Daryl W. Willmarth, Francis C. Fekel, Helmut A. Abt, Dimitri Pourbaix
Spectroscopic Orbits For 15 Late-Type Stars, Daryl W. Willmarth, Francis C. Fekel, Helmut A. Abt, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
Spectroscopic orbital elements are determined for 15 stars with periods from 8 to 6528 days with six orbits computed for the first time. Improved astrometric orbits are computed for two stars and one new orbit is derived. Visual orbits were previously determined for four stars, four stars are members of multiple systems, and five stars have Hipparcos "G" designations or have been resolved by speckle interferometry. For the nine binaries with previous spectroscopic orbits, we determine improved or comparable elements. For HD 28271 and HD 200790, our spectroscopic results support the conclusions of previous authors that the large values of …
Absolute Properties Of The Pre-Main-Sequence Eclipsing Binary Star Np Persei, Claud H. Sandberg Lacy, Francis C. Fekel, Krešimir Pavlovski, Guillermo Torres, Matthew W. Muterspaugh
Absolute Properties Of The Pre-Main-Sequence Eclipsing Binary Star Np Persei, Claud H. Sandberg Lacy, Francis C. Fekel, Krešimir Pavlovski, Guillermo Torres, Matthew W. Muterspaugh
Information Systems and Engineering Management Research Publications
NP Per is a well-detached, 2.2 day eclipsing binary whose components are both pre-main-sequence stars that are still contracting toward the main-sequence phase of evolution. We report extensive photometric and spectroscopic observations with which we have determined their properties accurately. Their surface temperatures are quite different: 6420 ± 90 K for the larger F5 primary star and 4540 ± 160 K for the smaller K5e star. Their masses and radii are 1.3207 ± 0.0087 solar masses and 1.372 ± 0.013 solar radii for the primary, and 1.0456 ± 0.0046 solar masses and 1.229 ± 0.013 solar radii for the secondary. …
The Spectroscopic Orbits Of Five Γ Doradus Stars, Francis C. Fekel, Gregory W. Henry, Dimitri Pourbaix
The Spectroscopic Orbits Of Five Γ Doradus Stars, Francis C. Fekel, Gregory W. Henry, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
We have determined the spectroscopic orbits of five γ Dor variables, HD 776, HD 6568, HD 17310, HD 19684, and HD 62196. Their orbital periods range from 27.8 to 1163 days and their eccentricities from 0.01 to 0.65. Of the five systems, only HD 19684 shows lines of its binary companion, but those lines are always so weak and blended with the lines of the primary that we were unable to measure them satisfactorily. The velocity residuals of the orbital fits were searched for periodicities associated with pulsation. No clear, convincing case for velocity periodicities in the residuals was found …
Hd 207651: A Composite Spectrum Triple System, Francis C. Fekel
Hd 207651: A Composite Spectrum Triple System, Francis C. Fekel
Information Systems and Engineering Management Research Publications
From numerous radial velocities obtained at KPNO and Fairborn Observatory, we have determined the orbital elements of the composite spectrum triple system HD 207651. This system consists of a broad-lined A8 V star and an unseen M dwarf companion in a 1.470739 days orbit. Variations of the center-of-mass velocity of this short-period system and velocity variations of a narrow-lined F7: V star have an orbital period of 724.1 days or 1.98 yr and an eccentricity of 0.39. The revised Hipparcos parallax, corresponding to a distance of 255 pc, appears to be too small to yield consistent properties. Instead, we adopt …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Ix. Hd 54371, Hr 2692, And 16 Ursa Majoris, Francis C. Fekel, Michael H. Williamson, Matthew W. Muterspaugh, Dimitri Pourbaix, Daryl W. Willmarth, Jocelyn Tomkin
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Ix. Hd 54371, Hr 2692, And 16 Ursa Majoris, Francis C. Fekel, Michael H. Williamson, Matthew W. Muterspaugh, Dimitri Pourbaix, Daryl W. Willmarth, Jocelyn Tomkin
Information Systems and Engineering Management Research Publications
With extensive sets of new radial velocities we have determined orbital elements for three previously known spectroscopic binaries, HD 54371, HR 2692, and 16 UMa. All three systems have had the lines of their secondaries detected for the first time. The orbital periods range from 16.24 to 113.23 days, and the three binaries have modestly or moderately eccentric orbits. The secondary to primary mass ratios range from 0.50 to 0.64. The orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) of the binary components all have accuracies of $\leqslant $1%. …
Absolute Properties Of The Eclipsing Binary Star Im Persei, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Matthew W. Muterspaugh, John Southworth
Absolute Properties Of The Eclipsing Binary Star Im Persei, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Matthew W. Muterspaugh, John Southworth
Information Systems and Engineering Management Research Publications
IM Per is a detached A7 eccentric eclipsing binary star. We have obtained extensive measurements of the light curve (28,225 differential magnitude observations) and radial velocity curve (81 spectroscopic observations) which allow us to fit orbits and determine the absolute properties of the components very accurately: masses of 1.7831 ± 0.0094 and 1.7741 ± 0.0097 solar masses, and radii of 2.409 ± 0.018 and 2.366 ± 0.017 solar radii. The orbital period is 2.25422694(15) days and the eccentricity is 0.0473(26). A faint third component was detected in the analysis of the light curves, and also directly observed in the spectra. …
Absolute Properties Of The Eclipsing Binary Star V501 Herculis, Claud H. Sandberg Lacy, Francis C. Fekel
Absolute Properties Of The Eclipsing Binary Star V501 Herculis, Claud H. Sandberg Lacy, Francis C. Fekel
Information Systems and Engineering Management Research Publications
V501 Her is a well detached G3 eclipsing binary star with a period of 8.597687 days for which we have determined very accurate light and radial-velocity curves using robotic telescopes. Results of these data indicate that the component stars have masses of 1.269 ± 0.004 and 1.211 ± 0.003 solar masses, radii of 2.001 ± 0.003 and 1.511 ± 0.003 solar radii, and temperatures of 5683 ± 100 K and 5720 ± 100 K, respectively. Comparison with the Yonsei–Yale series of evolutionary models results in good agreement at an age of about 5.1 Gyr for a somewhat metal-rich composition. Those …
Absolute Properties Of The Eclipsing Binary Star Ap Andromedae, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Matthew W. Muterspaugh
Absolute Properties Of The Eclipsing Binary Star Ap Andromedae, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Matthew W. Muterspaugh
Information Systems and Engineering Management Research Publications
AP And is a well-detached F5 eclipsing binary star for which only a very limited amount of information was available before this publication. We have obtained very extensive measurements of the light curve (19,097 differential V magnitude observations) and a radial velocity curve (83 spectroscopic observations) which allow us to fit orbits and determine the absolute properties of the components very accurately: masses of 1.277 ± 0.004 and 1.251 ± 0.004 M☉, radii of 1.233 ± 0.006 and 1.1953 ± 0.005 R☉, and temperatures of 6565 ± 150 K and 6495 ± 150 K. The distance to the system is …
The Orbits Of The Triple-Star System 1 Geminorum From Phases Differential Astrometry And Spectroscopy, Benjamin F. Lane, Matthew W. Muterspaugh, Roger F. Griffin, Colin D. Scarfe, Francis C. Fekel, Michael H. Williamson, Joel A. Eaton, Michael Shao, Mark M. Colavita, Maciej Konacki
The Orbits Of The Triple-Star System 1 Geminorum From Phases Differential Astrometry And Spectroscopy, Benjamin F. Lane, Matthew W. Muterspaugh, Roger F. Griffin, Colin D. Scarfe, Francis C. Fekel, Michael H. Williamson, Joel A. Eaton, Michael Shao, Mark M. Colavita, Maciej Konacki
Information Systems and Engineering Management Research Publications
We have used precise differential astrometry from the Palomar High-precision Astrometric Search for Exoplanet Systems project and radial-velocity measurements covering a time span of 40 yr to determine the orbital parameters of the 1 Geminorum triple system. We present the first detection of the spectral lines of the third component of the system, together with precise mass (0.5%) and distance (0.15%) determinations for this system. In addition, our astrometry allows us to make the first determination of the mutual inclination of the orbits.
Extensive Study Of Hd 25558, A Long-Period Double-Lined Binary With Two Spb Components, Á. Sódor, Peter De Cat, David J. Wright, Coralie Neiner, Maryline Briquet, Patricia Lampens, Robert J. Dukes, Gregory W. Henry, Michael H. Williamson, Emily Brunsden, Karen R. Pollard, Peter L. Cottrell, Florian Maisonneuve, Pam M. Kilmartin, Jaymie Matthews, Thomas Kallinger, Paul G. Beck, Eiji Kambe, Chris A. Engelbrecht, Robert J. Czanik, Stephenson Yang, Osamu Hashimoto, Satoshi Honda, Jian-Ning Fu, Barbara Castanheira, Holger Lehmann, Zsófia Bognár, Natalie Behara, Simone Scaringi, Hans Van Winckel, Jonathan Menu, Alex Lobel, P. Mathias, Sophie Saesen, Maja Vučković, The Mimes Collaboration
Extensive Study Of Hd 25558, A Long-Period Double-Lined Binary With Two Spb Components, Á. Sódor, Peter De Cat, David J. Wright, Coralie Neiner, Maryline Briquet, Patricia Lampens, Robert J. Dukes, Gregory W. Henry, Michael H. Williamson, Emily Brunsden, Karen R. Pollard, Peter L. Cottrell, Florian Maisonneuve, Pam M. Kilmartin, Jaymie Matthews, Thomas Kallinger, Paul G. Beck, Eiji Kambe, Chris A. Engelbrecht, Robert J. Czanik, Stephenson Yang, Osamu Hashimoto, Satoshi Honda, Jian-Ning Fu, Barbara Castanheira, Holger Lehmann, Zsófia Bognár, Natalie Behara, Simone Scaringi, Hans Van Winckel, Jonathan Menu, Alex Lobel, P. Mathias, Sophie Saesen, Maja Vučković, The Mimes Collaboration
Information Systems and Engineering Management Research Publications
We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The ≈2000 spectra obtained at different observatories, the ground-based and MOST satellite light curves revealed that this object is a double-lined spectroscopic binary with an orbital period of about nine years. The observations do not allow the inference of an orbital solution. We determined the physical parameters of the components, and found that both lie within the SPB instability strip. Accordingly, both show line-profile variations due to stellar pulsations. 11 independent frequencies were identified in the data. All the frequencies were attributed to one …
Absolute Properties Of The Eclipsing Binary Vv Corvi, Francis C. Fekel, Gregory W. Henry, James R. Sowell
Absolute Properties Of The Eclipsing Binary Vv Corvi, Francis C. Fekel, Gregory W. Henry, James R. Sowell
Information Systems and Engineering Management Research Publications
We have obtained red-wavelength spectroscopy and Johnson B and V differential photoelectric photometry of the eclipsing binary VV Crv = HR 4821. The system is the secondary of the common proper motion double star ADS 8627, which has a separation of 52. VV Crv has an orbital period of 3.144536 days and a low but non-zero eccentricity of 0.085. With the Wilson–Devinney program we have determined a simultaneous solution of our spectroscopic and photometric observations. Those orbital elements produce masses of M1 = 1.978 ± 0.010 M☉ and M2 = 1.513 ± 0.008 M☉, and …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Viii. Hr 1528, Hr 6993, 2 Sagittae, And 18 Vulpeculae, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Viii. Hr 1528, Hr 6993, 2 Sagittae, And 18 Vulpeculae, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson
Information Systems and Engineering Management Research Publications
Improved orbital elements for four A-star double-lined spectroscopic binaries have been determined with numerous new radial velocities. Three of the four systems, HR 1528, 2 Sge, and 18 Vul, have moderately short orbital periods of 7.05, 7.39, and 9.31 days, respectively, and also have circular or nearly circular orbits. Only HR 6993 with a period of 14.68 days has a significantly eccentric orbit. The close visual companion of 2 Sge has been detected spectroscopically, and its velocity measured. The orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) of the …
Astrometric Mass Ratios For Three Spectroscopic Binaries, Johannes Sahlmann, Francis C. Fekel
Astrometric Mass Ratios For Three Spectroscopic Binaries, Johannes Sahlmann, Francis C. Fekel
Information Systems and Engineering Management Research Publications
The orbits of five single-lined spectroscopic binaries have recently been determined. We now use astrometric measurements that were collected with the HIPPARCOS satellite to constrain the systems’ mass ratios and secondary masses. The barycentric astrometric orbits of three binary systems, HD 140667, HD 158222, and HD 217924, are fully determined and precise estimates of their mass ratios are obtained. Follow-up of these systems with infrared spectroscopy could yield model-independent dynamical masses for all components.
The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, Francis C. Fekel, Samira Rajabi, Matthew W. Muterspaugh, Michael H. Williamson
The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, Francis C. Fekel, Samira Rajabi, Matthew W. Muterspaugh, Michael H. Williamson
Information Systems and Engineering Management Research Publications
We have determined spectroscopic orbits for five single-lined spectroscopic binaries, HD 100167, HD 135991, HD 140667, HD 158222, HD 217924. Their periods range from 60.6 to 2403 days and the eccentricities from 0.20 to 0.84. Our spectral classes for the stars confirm that they are of solar type, F9–G5, and all are dwarfs. Their [Fe/H] abundances, determined spectroscopically, are close to the solar value and on average are 0.12 greater than abundances from a photometric calibration. Four of the five stars are rotating faster than their predicted pseudosynchronous rotational velocities.
The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, Francis C. Fekel, Michael H. Williamson, Michael Weber, Klaus G. Strassmeier, Dimitri Pourbaix
The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, Francis C. Fekel, Michael H. Williamson, Michael Weber, Klaus G. Strassmeier, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
We have determined an improved orbit for the bright, evolved, double lined binary γ Canis Minoris. The system has an orbital period of 389.31 days and an eccentricity of 0.2586. We have revised the secondary to primary mass ratio to 0.987. The spectral types of the primary and secondary are K4 III and K1: III, respectively, and the components have a V magnitude difference of 2.2. Orbital fits to the Hipparcos astrometry are not definitive, but they suggest an orbital inclination of ∼ 66°, which produces masses of 1.88 and 1.85 M⊙ for the components. A comparison with evolutionary tracks …
Absolute Properties Of The Eclipsing Binary Star V335 Serpentis, Claud H. Sandberg Lacy, Francis C. Fekel, Antonio Claret
Absolute Properties Of The Eclipsing Binary Star V335 Serpentis, Claud H. Sandberg Lacy, Francis C. Fekel, Antonio Claret
Information Systems and Engineering Management Research Publications
V335 Ser is now known to be an eccentric double-lined A1+A3 binary star with fairly deep (0.5 mag) partial eclipses. Previous studies of the system are improved with 7456 differential photometric observations from the URSA WebScope and 5666 from the NFO WebScope, and 67 high-resolution spectroscopic observations from the Tennessee State University 2 m automatic spectroscopic telescope. From dates of minima, the apsidal period is about 880 years. Accurate (better than 2%) masses and radii are determined from analysis of the two new light curves and the radial velocity curve. Theoretical models match the absolute properties of the stars at …
Absolute Properties Of The Eclipsing Binary Star Bf Draconis, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Jeffrey A. Sabby, Antonio Claret
Absolute Properties Of The Eclipsing Binary Star Bf Draconis, Claud H. Sandberg Lacy, Guillermo Torres, Francis C. Fekel, Jeffrey A. Sabby, Antonio Claret
Information Systems and Engineering Management Research Publications
BF Dra is now known to be an eccentric double-lined F6+F6 binary star with relatively deep (0.7 mag) partial eclipses. Previous studies of the system are improved with 7494 differential photometric observations from the URSA WebScope and 9700 from the NFO WebScope, 106 high-resolution spectroscopic observations from the Tennessee State University 2 m automatic spectroscopic telescope and the 1 m coudé-feed spectrometer at Kitt Peak National Observatory, and 31 accurate radial velocities from the CfA. Very accurate (better than 0.6%) masses and radii are determined from analysis of the two new light curves and four radial velocity curves. Theoretical models …
Third Component Search And Abundances Of The Very Dusty Short-Period Binary Bd +20°307, Francis C. Fekel, Maria J. Cordero, Raphael Galicher, Benjamin Zuckerman, Carl Melis, Alycia J. Weinberger
Third Component Search And Abundances Of The Very Dusty Short-Period Binary Bd +20°307, Francis C. Fekel, Maria J. Cordero, Raphael Galicher, Benjamin Zuckerman, Carl Melis, Alycia J. Weinberger
Information Systems and Engineering Management Research Publications
We have obtained near-infrared adaptive optics imaging and collected additional radial velocity observations to search for a third component in the extremely dusty short-period binary system BD +20°307. Our image shows no evidence for a third component at separations greater than 19 AU. Our four seasons of radial velocities have a constant center-of-mass velocity and are consistent with the systemic velocities determined at two earlier epochs. Thus, the radial velocities also provide no support for a third component. Unfortunately, the separation domains covered by our imaging and radial velocity results do not overlap. Thus, we examined the parameters for possible …
Retired A Stars And Their Companions. Vii. 18 New Jovian Planets, John Asher Johnson, Christian Clanton, Andrew W. Howard, Brendan P. Bowler, Gregory W. Henry, Geoffrey W. Marcy, Justin R. Crepp, Michael Endl, William D. Cochran, Phillip J. Macqueen, Jason T. Wright, Howard Isaacson
Retired A Stars And Their Companions. Vii. 18 New Jovian Planets, John Asher Johnson, Christian Clanton, Andrew W. Howard, Brendan P. Bowler, Gregory W. Henry, Geoffrey W. Marcy, Justin R. Crepp, Michael Endl, William D. Cochran, Phillip J. Macqueen, Jason T. Wright, Howard Isaacson
Information Systems and Engineering Management Research Publications
We report the detection of 18 Jovian planets discovered as part of our Doppler survey of subgiant stars at Keck Observatory, with follow-up Doppler and photometric observations made at McDonald and Fairborn Observatories, respectively. The host stars have masses 0.927 ⩽ M⋆/M☉ ⩽ 1.95, radii 2.5 ⩽ R⋆/R☉ ⩽ 8.7, and metallicities −0.46 ⩽ [Fe/H] ⩽+0.30. The planets have minimum masses 0.9 MJup ⩽ MPsin i ≲ 13 MJup and semimajor axes a ⩾ 0.76 AU. These detections represent a 50% increase in the number of planets known to orbit stars more massive than 1.5 M☉ and provide valuable additional …
Absolute Properties Of The Highly Eccentric, Solar-Type Eclipsing Binary Hd 74057, James R. Sowell, Gregory W. Henry, Francis C. Fekel
Absolute Properties Of The Highly Eccentric, Solar-Type Eclipsing Binary Hd 74057, James R. Sowell, Gregory W. Henry, Francis C. Fekel
Information Systems and Engineering Management Research Publications
We have obtained Strömgren b and y differential photometric observations of the solar-type eclipsing binary HD 74057 plus follow-up high-resolution, red wavelength spectroscopic observations. The system has an orbital period of 31.2198 days, a high eccentricity of 0.47, and is seen almost exactly edge on with an inclination of 89fdg8. The two main-sequence G0 stars are nearly identical in all physical characteristics. We used the Wilson–Devinney program to obtain a simultaneous solution of our photometric and spectroscopic observations. The resulting masses of the components are M1 = 1.138 ± 0.003 M☉ and M2 = 1.131 ± 0.003 M☉, and the …
Absolute Properties Of The Eclipsing Binary Star Hy Virginis, Claud H. Sandberg Lacy, Francis C. Fekel
Absolute Properties Of The Eclipsing Binary Star Hy Virginis, Claud H. Sandberg Lacy, Francis C. Fekel
Information Systems and Engineering Management Research Publications
HY Vir is found to be a double-lined F0m+F5 binary star with relatively shallow (0.3 mag) partial eclipses. Previous studies of the system are improved with 7509 differential photometric observations from the URSA WebScope and 8862 from the NFO WebScope, and 68 high-resolution spectroscopic observations from the Tennessee State University 2 m automatic spectroscopic telescope, and the 1 m coudé-feed spectrometer at Kitt Peak National Observatory. Very accurate (better than 0.5%) masses and radii are determined from analysis of the new light curves and radial velocity curves. Theoretical models match the absolute properties of the stars at an age of …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Vii. 47 Andromedae, 38 Cassiopeiae, And Hr 8467, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson, Dimitri Pourbaix
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Vii. 47 Andromedae, 38 Cassiopeiae, And Hr 8467, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
Improved orbital elements for three double-lined spectroscopic binaries, 47 And, 38 Cas, and HR 8467, have been determined with extensive new radial velocities. For 38 Cas lines of the secondary have been detected for the first time. Given the orbital periods for these systems of 35.3682, 134.130, and 42.3813 days, respectively, it is not surprising that all three have either moderate or relatively high eccentricities. The orbital dimensions (a1sin i and a2sin i) and minimum masses (m1sin 3i and m2sin 3i) have accuracies of 0.5% or better. An astrometric orbit for 38 Cas, which was recomputed with Hipparcos astrometry and …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Vi. Hd 24623 And V923 Scorpii, Francis C. Fekel, Michael H. Williamson, Gregory W. Henry
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Vi. Hd 24623 And V923 Scorpii, Francis C. Fekel, Michael H. Williamson, Gregory W. Henry
Information Systems and Engineering Management Research Publications
Using new radial velocities obtained at KPNO and Fairborn Observatory, we have determined improved spectroscopic orbits for two double-lined F-type binaries, HD 24623 and V923 Sco. The orbital periods are 19.66304 and 34.8386 days, respectively, so it is not surprising that their orbits have relatively high eccentricities of nearly 0.5. The orbital dimensions (a1sin i and a2sin i) and minimum masses (m1sin 3i and m2sin 3i) have accuracies of 0.2% or better. Extensive photometry of HD 24623 with the T4 0.75 m automatic photometric telescope at Fairborn Observatory shows no evidence of eclipses. Instead, a very weak reflection effect is …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. V. The Am Stars Hd 434 And 41 Sextantis, Francis C. Fekel, Michael H. Williamson
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. V. The Am Stars Hd 434 And 41 Sextantis, Francis C. Fekel, Michael H. Williamson
Information Systems and Engineering Management Research Publications
We have detected the secondary component in two previously known spectroscopic binaries, HD 434 and 41 Sex, and for the first time determined double-lined orbits for them. Despite the relatively long period of 34.26 days and a moderate eccentricity of 0.32, combined with the components' rotationally broadened lines, measurement of the primary and secondary radial velocities of HD 434 has enabled us to obtain significantly improved orbital elements. While the 41 Sex system has a much shorter period of 6.167 days and a circular orbit, the estimated V mag difference of 3.2 between its components also makes this a challenging …
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Iv. 66 Andromedae, Hr 6979, And Hr 9059, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson
New Precision Orbits Of Bright Double-Lined Spectroscopic Binaries. Iv. 66 Andromedae, Hr 6979, And Hr 9059, Francis C. Fekel, Jocelyn Tomkin, Michael H. Williamson
Information Systems and Engineering Management Research Publications
We have determined improved spectroscopic orbits for three double-lined binaries, 66 And (F4 V), HR 6979 (Am), and HR 9059 (F5 IV) using radial velocities from the 2.1 m telescope at McDonald Observatory, the coudé feed telescope at Kitt Peak National Observatory, and 2 m telescope at Fairborn Observatory. The orbital periods range from 11.0 to 14.3 days, and all three systems have eccentric orbits. The new orbital dimensions (a1 sin i and a2 sin i) and minimum masses (m1 sin3 i and m2 sin3 i) have accuracies of 0.2% or better. All six components of the three binary systems …