Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.1
2.5
Journals
Galaxies
Special Issues
What’s New under the Binary Suns
share announcement

What’s New under the Binary Suns

A special issue of Galaxies (ISSN 2075-4434).

Deadline for manuscript submissions: closed (1 December 2021) | Viewed by 23197

Special Issue Editors

Prof. Robert E. Wilson

E-Mail Website
Guest Editor
Astronomy Department, University of Florida, Gainesville, FL 32611, USA
Interests: stellar astronomy/astrophysics
Prof. Walter Van Hamme

E-Mail Website
Guest Editor
Department of Physics, Florida International University, Miami, FL 33199, USA
Interests: interacting binary stars; binary star structure and evolution

Special Issue Information

Dear Colleagues,

As in other astrophysical areas, the cornerstones of close binary research are observation, theory, and their tie rod -- analysis.

Either observation or theory can be ahead at a given time, while an era of matching strength can generate rapid progress. This issue examines areas within the close binary field that are currently advancing due to unprecedented instrumental development and a conceptual harvest in theory and analysis that has followed from ever more penetrating computational capabilities. For example, understanding of accretion and decretion disks in binaries has benefitted from time-varying fluid dynamic models (theory), ultraviolet spectra from space missions (observation), and generation of synthetic light curves and spectra (analysis). Although some disks are confidently known to be optically thin and others optically thick, the intermediate (semi-transparent) case is not yet well enough modeled to match the quality of current observations.

Areas in roughly similar developmental states (observation vs. theory) include common envelope binaries - currently understood to be precursors of cataclysmic variables (CVs), the CVs themselves (post novae, nova-like variables, recurrent novae, and the several varieties of dwarf novae), pulsation in close binaries, and the fundamental area of binary system morphology (detached, semi-detached, overcontact, and double-contact types). Analytic improvements continue, while several have been published but have not yet come into widespread application.

The thrust of this issue is to spur communication among thinkers and developers in these timely areas.

References:

  1. Mitnyan, T.; Borkovits, T.; Rappaport, S.A.; Pál, A.; Maxted, P.F.L. TIC 278825952: a Triply Eclipsing Hierarchical Triple System with the Most Intrinsically Circular Outer Orbit. Mon. Not. R. Astron. Soc. 2020, 498, 6034–6043.
  2. Eaton, J.A. AW Ursae Majoris: A Semidetached Mass-transferring System Indeed? Mon. Not. R. Astron. Soc. 2016, 457, 836.
  3. Kallrath, J.; Milone, E.F. Eclipsing Binary Stars: Modeling and Analysis. 2nd edition; Springer Publ.: New York, NY, USA, 2009; 424 pages.
  4. Mennickent, R.E. Long Photometric Cycles in Hot Algols. Serb. Astron. J. 2017, 194, 1–21.
  5. Mkrtichian, D.E.; Lehmann, H.; Rodriguez, E. et al. The Eclipsing Binary Star RZ Cas: Accretion-driven Variability of the Multimode Oscillation Spectrum. Mon. Not. R. Astron. Soc. 2018, 475, 4745.
  6. Morales, J.C.; Ribas, I.; Jordi, C. Low-Mass Eclipsing Binaries: Observations vs. Theory. In proceedings of 16th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun. Seattle, WA, USA, 28 August–2 September, 2010. Astronomical Society of the Pacific, 2011, 448, 99.
  7. Peters, G.J.; Wang, L.; Gies, D.R.; Grundstrom, E.D. The Hot Companion and Circumbinary Disk of the Be star HR 2142. Astrophys. J. 2016, 828, 47.
  8. Prša, A.; Conroy, K.E.; Horvat, M.; Pablo, H.; Kochoska, A.; Bloemen, S.; Giammarco, J.; Hambleton, K.M.; Degroote, P. Physics OF Eclipsing Binaries. II. Toward the Increased Model Fidelity, Astrophys. J., Suppl. Ser. 2016, 227, 29.
  9. Sobolev, A.V.; Zhilkin, A.G.; Bisikalo, D.V.; Buckley, D.A.H. Three-Dimensional Numerical Simulation of a Flow Structure in the Asynchronous Polar CD Ind in the Approximation of an Offset Dipole Magnetic Field of a White Dwarf. Astron. Rep. 2020, 64, 467.
  10. Terrell, D.; Wilson, R.E. Photometric Mass Ratios of Eclipsing Binary Stars. Astrophys. Space Sci. 2005, 296, 221.
  11. Torres, G.; Curtis, J.L.; Vanderburg, A.; Kraus, A.L.; Rizzuto, A. Eclipsing Binaries in the Open Cluster Ruprecht 147. I. EPIC 219394517. Astrophys. J. 2018, 866, 67.
  12. Wilson, R.E. Self-gravitating Semi-transparent Circumstellar Disks: An Analytic Model. Astrophys. J. 2018, 869, 19.

Prof. Robert E. Wilson
Prof. Walter Van Hamme
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Galaxies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • stars: binary eclipsing
  • spectroscopic
  • cataclysmic
  • common envelope

Published Papers (10 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

14 pages, 549 KiB  
Article
Fundamental Properties of Late-Type Stars in Eclipsing Binaries
by Juan Carlos Morales, Ignasi Ribas, Álvaro Giménez and David Baroch
Galaxies 2022, 10(5), 98; https://doi.org/10.3390/galaxies10050098 - 17 Sep 2022
Cited by 6 | Viewed by 1558
Abstract
Evidence from the analysis of eclipsing binary systems revealed that late-type stars are larger and cooler than predicted by models, and that this is probably caused by stellar magnetic activity. In this work, we revisit this problem taking into account the advancements in [...] Read more.
Evidence from the analysis of eclipsing binary systems revealed that late-type stars are larger and cooler than predicted by models, and that this is probably caused by stellar magnetic activity. In this work, we revisit this problem taking into account the advancements in the last decade. We provide and updated a list of 32 eclipsing binary or multiple systems, including at least one star with a mass ≲0.7 M⊙ and with mass and radius measured to an accuracy better than 3%. The comparison with stellar structure and evolution theoretical models reveals an overall discrepancy of about 7% and −4% for the radius and effective temperature, respectively, and that it may be larger than previously found below the full convection boundary. Furthermore, the hypothesis of stellar activity is reinforced by the comparison of different systems with similar components. Further eclipsing binaries with accurately determined masses and radii, and with estimated activity levels, as well as the implementation of magnetic activity in theoretical models will help to improve our knowledge of low-mass stars, which are prime targets for exoplanet surveys. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

15 pages, 1374 KiB  
Article
Mass-Accreting Pulsating Components of Algols
by David Mkrtichian, Khemsinan Gunsriviwat, Holger Lehmann, Chris Engelbrecht, Andrew Tkachenko and Victor Nazarenko
Galaxies 2022, 10(5), 97; https://doi.org/10.3390/galaxies10050097 - 16 Sep 2022
Cited by 3 | Viewed by 1926
Abstract
We present a review of the latest results of studies of the class of mass-accreting pulsating components of semi-detached eclipsing binaries known as oEA stars. The application of the techniques of asteroseismology to this class of stars unlocks new pathways for gaining a [...] Read more.
We present a review of the latest results of studies of the class of mass-accreting pulsating components of semi-detached eclipsing binaries known as oEA stars. The application of the techniques of asteroseismology to this class of stars unlocks new pathways for gaining a deeper understanding of the short-term evolution and magnetic activity of binary stars. We report the discovery of 49 new pulsating components of eclipsing binaries, based on data from NASA’s TESS space telescope. Recent observational results on the pulsation characteristics of these stars are summarized. The effects of the interaction of the magnetic and spot activity of the Roche-lobe-filling component of a system with the pulsations of the mass-accreting component are discussed. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

8 pages, 559 KiB  
Article
On Variation Mechanisms in Recurrent Nova IM Normae
by R. E. Wilson
Galaxies 2022, 10(5), 96; https://doi.org/10.3390/galaxies10050096 - 14 Sep 2022
Viewed by 1152
Abstract
Light curves by Woudt and Warner (WW) of recurrent nova IM Nor show eclipse-like dips that they saw as too wide for eclipses alone, and interpreted as mainly a reflection effect due to irradiation of the companion (mass donor) star with some amplitude [...] Read more.
Light curves by Woudt and Warner (WW) of recurrent nova IM Nor show eclipse-like dips that they saw as too wide for eclipses alone, and interpreted as mainly a reflection effect due to irradiation of the companion (mass donor) star with some amplitude increase due to eclipse of IM Nor’s disk. A mainly reflection interpretation cannot be made to work because reflection does not produce dips over a restricted phase range but a somewhat distorted sinusoid that extends over the entire orbital cycle. Here, the dip features are interpreted in two ways, with testing via quantitative light curve modeling that includes an equipotential disk. One way is as alternating eclipses of and by the disk that surrounds this cataclysmic variable’s accreting white dwarf, rather than purely a succession of disk-by-star eclipses. WW’s estimated period of 0.d1026 was accordingly doubled to 0.d2052, with the observed dips now half of their previous width in phase, and with the modeled eclipses matching the observed dips in width and shape. In the 2nd interpretation, a toroidal disk’s capability to produce very wide eclipses is demonstrated computationally. Furthermore, much of the perceived eclipse width can be recognized as an apparent effect due to tidal stretching of the companion star and the disk. In overview, disk eclipses and tidal variation combine with reflection to produce a light curve waveform of approximately the observed shape and duration. Eclipses, tides, and reflection all have essential roles in the 2nd interpretation and no change from WW’s period is needed. Radial velocity observations will be crucial for identification of the correct resolution of the ”excessively wide eclipse” problem. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

9 pages, 380 KiB  
Article
Mass Ratio and Spot Parameter Estimation from Eclipsing Binary Star Light Curves
by Dirk Terrell
Galaxies 2022, 10(1), 8; https://doi.org/10.3390/galaxies10010008 - 5 Jan 2022
Cited by 15 | Viewed by 2397
Abstract
Eclipsing binary stars have a rich history of contributing to the field of stellar astrophysics. Most of the available information on the fundamental properties of stars has come from the analysis of observations of binaries. The availability of powerful computers and sophisticated codes [...] Read more.
Eclipsing binary stars have a rich history of contributing to the field of stellar astrophysics. Most of the available information on the fundamental properties of stars has come from the analysis of observations of binaries. The availability of powerful computers and sophisticated codes that apply physical models has resulted in determinations of masses and radii of sufficient accuracy to provide critical tests of theories of stellar structure and evolution. Despite their sophistication, these codes still require the guiding hand of trained scientists to extract reliable information. The computer code will produce results, but it is still imperative for the analyst to ensure that those results make astrophysical sense, and to ascertain their reliability. Care must be taken to ensure that we are asking the codes for parameters for which there is information in the data. The analysis of synthetic observations with simulated observational errors of typical size can provide valuable insight to the analysis process because the parameters used to generate the observations are known. Such observations are herein analyzed to guide the process of determining mass ratios and spot parameters from eclipsing binary light curves. The goal of this paper is to illustrate some of the subtleties that need to be recognized and treated properly when analyzing binary star data. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

11 pages, 340 KiB  
Article
A Stringent Test of Magnetic Models of Stellar Evolution
by Guillermo Torres, Gregory A. Feiden, Andrew Vanderburg and Jason L. Curtis
Galaxies 2022, 10(1), 3; https://doi.org/10.3390/galaxies10010003 - 24 Dec 2021
Cited by 4 | Viewed by 2437
Abstract
Main-sequence stars with convective envelopes often appear larger and cooler than predicted by standard models of stellar evolution for their measured masses. This is believed to be caused by stellar activity. In a recent study, accurate measurements were published for the K-type components [...] Read more.
Main-sequence stars with convective envelopes often appear larger and cooler than predicted by standard models of stellar evolution for their measured masses. This is believed to be caused by stellar activity. In a recent study, accurate measurements were published for the K-type components of the 1.62-day detached eclipsing binary EPIC 219511354, showing the radii and temperatures for both stars to be affected by these discrepancies. This is a rare example of a system in which the age and chemical composition are known, by virtue of being a member of the well-studied open cluster Ruprecht 147 (age~3 Gyr, [Fe/H] = +0.10). Here, we report a detailed study of this system with nonstandard models incorporating magnetic inhibition of convection. We show that these calculations are able to reproduce the observations largely within their uncertainties, providing robust estimates of the strength of the magnetic fields on both stars: 1600 ± 130 G and 1830 ± 150 G for the primary and secondary, respectively. Empirical estimates of the magnetic field strengths based on the measured X-ray luminosity of the system are roughly consistent with these predictions, supporting this mechanism as a possible explanation for the radius and temperature discrepancies. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

34 pages, 10950 KiB  
Article
Hot Spots Drift in Synchronous and Asynchronous Polars: Results of Three-Dimensional Numerical Simulation
by Dmitry Bisikalo, Andrey Sobolev and Andrey Zhilkin
Galaxies 2021, 9(4), 110; https://doi.org/10.3390/galaxies9040110 - 28 Nov 2021
Cited by 2 | Viewed by 2200
Abstract
In this paper, the characteristics of hot spots on an accretor surface are investigated for two types of polars: the eclipsing synchronous polar V808 Aur and the non-eclipsing asynchronous polar CD Ind in configuration of an offset and non-offset magnetic dipole. The drift [...] Read more.
In this paper, the characteristics of hot spots on an accretor surface are investigated for two types of polars: the eclipsing synchronous polar V808 Aur and the non-eclipsing asynchronous polar CD Ind in configuration of an offset and non-offset magnetic dipole. The drift of hot spots is analyzed based on the results of numerical calculations and maps of the temperature distribution over the accretor surface. It is shown that a noticeable displacement of the spots is determined by the ratio of ballistic and magnetic parts of the jet trajectory. In the synchronous polar, the dominant influence on the drift of hot spots is exerted by variations in the mass transfer rate, which entail a change in the ballistic part of the trajectory. It was found that when the mass transfer rate changes within the range of 10−10M⊙/year to 10−7M⊙/year, the displacement of the hot spot in latitude and longitude can reach 30∘. In the asynchronous polar, a change in the position of hot spots is mainly defined by the properties of the white dwarf magnetosphere, and the displacement of hot spots in latitude and longitude can reach 20∘. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

Review

Jump to: Research

13 pages, 560 KiB  
Review
The Accreting White Dwarfs in Cataclysmic Variables
by Edward M. Sion and Patrick Godon
Galaxies 2022, 10(2), 43; https://doi.org/10.3390/galaxies10020043 - 7 Mar 2022
Cited by 4 | Viewed by 2865
Abstract
Accreting white dwarfs (WDs) in cataclysmic variables (CVs) provide crucial insights about the accretion of mass and angular momentum in all types of binaries, including accreting NSs and BHs. Accreting WDs are the critical component in the single degenerate pathway to SNe Ia, [...] Read more.
Accreting white dwarfs (WDs) in cataclysmic variables (CVs) provide crucial insights about the accretion of mass and angular momentum in all types of binaries, including accreting NSs and BHs. Accreting WDs are the critical component in the single degenerate pathway to SNe Ia, along with the double degenerate merger pathway, they are the standard candles of cosmology proving that the universe is accelerating and the existence of dark energy. Another key question is whether the WD in a CV can grow in mass despite the mass loss due to thousands of nova explosions in its lifetime. Angular momentum loss drives CV evolution and accreting WDs offer critically needed WD masses from Gaia distances and reliable surface temperatures to derive the most accurate accretion rates. We review the studies on accreting WDs, including WD masses, accurate rotational velocities and chemical abundances of elements. Most of the progress that has been made is based upon Hubble Space Telescope spectroscopy and FUSE spectroscopy in the UV spectral region during dwarf nova quiescence and the low states of novalike variables, when the accreting WD dominates the UV spectral range. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

13 pages, 274 KiB  
Review
Fifty Years of Eclipsing Binary Analysis with the Wilson–Devinney Model
by Josef Kallrath
Galaxies 2022, 10(1), 17; https://doi.org/10.3390/galaxies10010017 - 19 Jan 2022
Cited by 1 | Viewed by 2706
Abstract
The Wilson–Devinney model has—over the last 50 years—become the standard in analyzing eclipsing binary observations. To provide orientation for both active binary and non-binary researchers, it is presented here in historical and on-going as well as astrophysical perspectives. Among the important advances that [...] Read more.
The Wilson–Devinney model has—over the last 50 years—become the standard in analyzing eclipsing binary observations. To provide orientation for both active binary and non-binary researchers, it is presented here in historical and on-going as well as astrophysical perspectives. Among the important advances that originated with the model are: the representation of star surfaces as equipotentials for circular and eccentric orbits, leading to four morphological types; simultaneous least-squares light and velocity curve analyses; efficient reflection computation, including multiple reflection; disk theory and disk modeling. Solutions in physical units allowed for the accurate estimation of parameters such as stellar masses and photometric distances; inclusion of types of observables, properly weighted. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
11 pages, 1652 KiB  
Review
Accretion Disks and Long Cycles in β Lyrae-Type Binaries
by R. E. Mennickent
Galaxies 2022, 10(1), 15; https://doi.org/10.3390/galaxies10010015 - 18 Jan 2022
Cited by 2 | Viewed by 2048
Abstract
In order to inquire about the nature of the accretion disks formed around the more massive companion in binaries with β Lyrae-type light curves, we review literature presenting some physical and observational properties of these systems. In addition, we inspect the photometric time [...] Read more.
In order to inquire about the nature of the accretion disks formed around the more massive companion in binaries with β Lyrae-type light curves, we review literature presenting some physical and observational properties of these systems. In addition, we inspect the photometric time series of three representative eclipsing systems obtained by the Optical Gravitational Lensing Experiment (OGLE) project during the last decades and compare them with β Lyrae. All these three systems show indications of being semidetached with a more massive B-type component and in a mass transfer stage. They also show long photometric cycles, and two of them show changes in the orbital light curve that can be interpreted in terms of structural changes of the accretion disks, eventually driven by variations in the mass transfer rate. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

38 pages, 1961 KiB  
Review
Eclipsing Binaries in Dynamically Interacting Close, Multiple Systems
by Tamás Borkovits
Galaxies 2022, 10(1), 9; https://doi.org/10.3390/galaxies10010009 - 6 Jan 2022
Cited by 20 | Viewed by 2922
Abstract
Close, compact, hierarchical, and multiple stellar systems, i.e., multiples having an outer orbital period from months to a few years, comprise a small but continuously growing group of the triple and multiple star zoo. Many of them consist of at least one eclipsing [...] Read more.
Close, compact, hierarchical, and multiple stellar systems, i.e., multiples having an outer orbital period from months to a few years, comprise a small but continuously growing group of the triple and multiple star zoo. Many of them consist of at least one eclipsing pair of stars and, therefore, exhibit readily observable short-term dynamical interactions among the components. Thus, their dynamical and astrophysical properties can be explored with high precision. In this paper we present an overview of the history of the search for additional components around eclipsing binaries from the first serendipitous discoveries to more systematic recent studies. We describe the different observational detection methods and discuss their connections to the different kinds of astrophysical and dynamical information that can be mined from different datasets. Moreover, the connection amongst the observable phenomena and the long-term dynamics of such systems is also discussed. Full article
(This article belongs to the Special Issue What’s New under the Binary Suns)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-10
Back to TopTop