scholarly journals Light curve modeling of the short-period W UMa star GSC 02049-01164

2015 ◽  
Vol 11 (A29B) ◽  
pp. 536-539
Author(s):  
Lester Fox-Machado ◽  
Juan Echevarria ◽  
Diego González-Buitrago ◽  
Raul Michel
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Binary Stars ◽  
Binary Star ◽  
Major Axis ◽  
Physical Parameters ◽  
Semi Major Axis ◽  
San Pedro ◽  
Short Period ◽  
Curve Modeling

AbstractThe preliminary results of an analysis of the time-series photometric data of binary star GSC 02049-01164 (ROTSE1 J164341.65+251748.1) are presented. GSC 02049-01164 was observed for eight consecutive nights with the 0.84-m telescope of the San Pedro Martir Observatory in Mexico. The light curve of GSC 02049-01164 is typical of those of W UMa type binary stars. In an effort to gain a better understanding of the binary system and determine its physical properties we have analyzed the light curve with the software PHOEBE V.0 0.31a. We have found that GSC 02049-01164 binary system has a mass ratio of ~ 0.42, an inclination of ~ 85 degrees, a semi-major axis of ~ 2.24 R⊙. It is likely that the two stellar components are in contact, with a degree of overcontact of 13%. The physical parameters of the stellar components have been derived.

scholarly journals Orbital Elements of MACHO Project Eclipsing Binary Stars

2005 ◽  
Vol 13 ◽  
pp. 467-467
Author(s):  
Charles Alcock
Keyword(s):  
Binary Stars ◽  
Large Scale ◽  
Major Axis ◽  
Orbital Elements ◽  
Semi Major Axis ◽  
Eclipsing Binary ◽  
Eclipsing Binary Stars ◽  
Large Numbers ◽  
Short Period ◽  
Velocity Information

Large scale photometric surveys can deliver very large numbers of eclipsing binary stars. It is not presently possible to obtain radial velocity information for more than a small fraction of these. We have made some progress in the estimation of the statistical distributions of orbital elements (including semi-major axis and eccentricity) in the MACHO Project catalog of eclipsing binary stars. We see the well-known tendency to circularization in short period orbits and also detect late tidal circularization during the giant phase. The extension of these techniques to newer surveys will also be discussed.

scholarly journals MCMCI: A code to fully characterise an exoplanetary system

2020 ◽  
Vol 635 ◽  
pp. A6 ◽  
Author(s):  
A. Bonfanti ◽  
M. Gillon
Keyword(s):  
Time Series ◽  
Light Curve ◽  
Radial Velocity ◽  
Global Analysis ◽  
Major Axis ◽  
Theoretical Models ◽  
Integrated Analysis ◽  
Physical Parameters ◽  
Light Curve Analysis ◽  
Semi Major Axis

Context. Useful information can be retrieved by analysing the transit light curve of a planet-hosting star or induced radial velocity oscillations. However, inferring the physical parameters of the planet, such as mass, size, and semi-major axis, requires preliminary knowledge of some parameters of the host star, especially its mass or radius, which are generally inferred through theoretical evolutionary models. Aims. We seek to present and test a whole algorithm devoted to the complete characterisation of an exoplanetary system thanks to the global analysis of photometric or radial velocity time series combined with observational stellar parameters derived either from spectroscopy or photometry. Methods. We developed an integrated tool called MCMCI. This tool combines the Markov chain Monte Carlo (MCMC) approach of analysing photometric or radial velocity time series with a proper interpolation within stellar evolutionary isochrones and tracks, known as isochrone placement, to be performed at each chain step, to retrieve stellar theoretical parameters such as age, mass, and radius. Results. We tested the MCMCI on the HD 219134 multi-planetary system hosting two transiting rocky super Earths and on WASP-4, which hosts a bloated hot Jupiter. Even considering different input approaches, a final convergence was reached within the code, we found good agreement with the results already stated in the literature and we obtained more precise output parameters, especially concerning planetary masses. Conclusions. The MCMCI tool offers the opportunity to perform an integrated analysis of an exoplanetary system without splitting it into the preliminary stellar characterisation through theoretical models. Rather this approach favours a close interaction between light curve analysis and isochrones, so that the parameters recovered at each step of the MCMC enter as inputs for purposes of isochrone placement.

scholarly journals New Data on the Eclipsing Binary V1848 Ori and Improved Orbital and Light Curve Solutions

2020 ◽  
Vol 29 (1) ◽  
pp. 72-80 ◽  
Author(s):  
Fatemeh Davoudi ◽  
Atila Poro ◽  
Fahri Alicavus ◽  
Afshin Halavati ◽  
Saeed Doostmohammadi ◽  
...  
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Mass Function ◽  
Light Curves ◽  
Complete Analysis ◽  
Physical Parameters ◽  
Mass Ratio ◽  
Third Body ◽  
Eclipsing Binary

AbstractNew observations of the eclipsing binary system V1848 Ori were carried out using the V filter resulting in a determination of new times of minima and new ephemeris were obtained. We presented the first complete analysis of the system’s orbital period behavior and analysis of O-C diagram done by the GA and MCMC approaches in OCFit code. The O-C diagram demonstrates a sinusoidal trend in the data; this trend suggests a cyclic change caused by the LITE effect with a period of 10.57 years and an amplitude of 7.182 minutes. It appears that there is a third body with mass function of f (m3) = 0.0058 M⊙ in this binary system. The light curves were analyzed using the Wilson-Devinney code to determine some geometrical and physical parameters of the system. These results show that V1848 Ori is a contact W UMa binary system with the mass ratio of q = 0.76 and a weak fillout factor of 5.8%. The O’Connell effect was not seen in the light curve and there is no need to add spot.

scholarly journals Physical Parameters and Chemical Composition of Components of the Am-Type Binary System RR Lyncis

1993 ◽  
Vol 138 ◽  
pp. 192-196
Author(s):  
L.S. Lyubimkov ◽  
T.M. Rachkovskaya
Keyword(s):  
Chemical Composition ◽  
Binary System ◽  
Binary Stars ◽  
Spectroscopic Binaries ◽  
Theoretical Modelling ◽  
Physical Parameters ◽  
Accurate Data ◽  
Element Abundances ◽  
Widespread Phenomenon ◽  
Chemical Anomalies

Duplicity is a very widespread phenomenon among Am-stars. For instance, Abt (1961) investigating 25 such stars found out that 22 of them are spectroscopic binaries. However this important phenomenon is ignored usually in chemical composition investigations of Am-stars. Consequently some “mean” element abundances are determined, which can noticeably differ from real abundances in atmospheres of components. Moreover false chemical anomalies can appear, as shown by the theoretical modelling of spectra of binary stars (Lyubimkov, 1989, 1992). Meanwhile accurate data on chemical composition of Am-stars must be considered as observational test for any hypothesis suggested for explanation of these objects.

scholarly journals 22. The relation between orbits and physical characteristics of meteors

1968 ◽  
Vol 33 ◽  
pp. 217-235 ◽  
Author(s):  
Ľ. Kresák
Keyword(s):  
Major Axis ◽  
Progressive Increase ◽  
Physical Characteristics ◽  
The Other ◽  
Asteroid Belt ◽  
Angle Of Incidence ◽  
Semi Major Axis ◽  
Short Period ◽  
Broad Variety ◽  
Bona Fide

The relation of physical characteristics of meteors to their orbital elements is investigated using Harvard Super-Schmidt data. A set of characteristic indices is defined, allowing for the effects of geocentric velocity, angle of incidence, magnitude and mass, wherever a correction appears appropriate according to the correlations found by Jacchia et al. (1967). The medians for representative meteor samples are plotted in the semi-major axis/eccentricity diagram and the distribution of each parameter is derived. Although the differences are moderate compared to the measuring errors, six regions of different nature can be distinguished.The existence of two families of asteroidal meteors is indicated, one of them brought to crossing with the Earth's orbit by drag effects and the other by collision effects in the main asteroid belt. These meteors are characterized by low and uniform beginning heights, high fragmentation, low ablation, low deceleration, and bright wakes. A direct counterpart to this is represented by meteors moving in short-period orbits of higher eccentricity and shorter perihelion distance, which bear resemblance to the long-period and retrograde cometary meteors. Meteors with perihelion distances of less than 0·15 AU tend to resemble the bona fide asteroidal meteors by a progressive increase of fragmentation and decrease of reduced beginning heights and decelerations as the perihelion approaches the Sun. This is attributed to the selective destruction effects of solar radiation.With the exception of the Draconids, the mean characteristics of meteor showers agree well with those of sporadic meteors moving in similar orbits. It is suggested that the Draconid stream includes a broad variety of meteoric material and that the two peculiar Super-Schmidt meteors on record represent only the less resistive, short-lived component which has already been eliminated from the other showers.

scholarly journals Synthetic Light-Curve Analysis of a Short Period Binary System YY Eri

2021 ◽  
Vol 58 (1) ◽  
pp. 5454-5456
Author(s):  
Warisa Pancharoen, Wiraporn Maithong
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Effective Temperature ◽  
Curve Analysis ◽  
Photometric System ◽  
Mass Ratio ◽  
Light Curve Analysis ◽  
The Public ◽  
Secondary Star ◽  
Short Period

YY Eri, the short-period binary system, is a W UMa type of the eclipsing binary system. This study using a 0.7-meter telescope with CCD photometric system in B V and R filters. It was observed at the Regional Observatory for the Public, Chachoengsao, Thailand on December 5, 2018, UT. The MaxIm DL software was used to analyzed the images photometry to produce the light curve. The Wilson-Devinney technique was computed the synthetic light curve that prefer to the physical properties of the YY Eri. The results show that the effective temperature of the primary and secondary star was 5533 and 5598 K, respectively. The inclination is 81.450 and the mass ratio is 0.55. The degree of contact was calculated as 16.64%  

scholarly journals A New Binary Star System of EW Type in Draco: GSC 03905-01870

2018 ◽  
Author(s):  
Salvador Barquin
Keyword(s):  
Light Curve ◽  
Binary Stars ◽  
Variable Star ◽  
Binary Star ◽  
Type I ◽  
Star System ◽  
Primary Minimum ◽  
Eclipsing Binary ◽  
Eclipsing Binary Stars ◽  
Binary Star System

Discovery of a new binary star system (GSC 03905-01870 = USNO-B1.0 1431-0327922 = UCAC4 716-059522) in the Draco constellation is presented. It was discovered during a search for previously unreported eclipsing binary stars through the ASAS-SN database. The shape of the light curve and its characteristics (period of 0.428988±0.000001 d, amplitude of 0.34±0.02 V Mag, primary minimum epoch HJD 2457994.2756±0.0002) indicates that the new variable star is an eclipsing binary of W Ursae Majoris type. I registered this variable star in The International Variable Star Index (VSX), its AAVSO UID is 000-BMP-891.

scholarly journals Spot evolution in the eclipsing binary CoRoT 105895502

2019 ◽  
Vol 623 ◽  
pp. A107 ◽  
Author(s):  
S. Czesla ◽  
S. Terzenbach ◽  
R. Wichmann ◽  
J. H. M. M. Schmitt
Keyword(s):  
Light Curve ◽  
Binary Systems ◽  
Temporal Behavior ◽  
Mass Ratio ◽  
Late Type ◽  
Stellar Rotation ◽  
Orbital Inclination ◽  
Eclipsing Binary ◽  
Short Period ◽  
Curve Modeling

Stellar activity is ubiquitous in late-type stars. The special geometry of eclipsing binary systems is particularly advantageous to study the stellar surfaces and activity. We present a detailed study of the 145 d CoRoT light curve of the short-period (2.17 d) eclipsing binary CoRoT 105895502. By means of light-curve modeling with Nightfall, we determine the orbital period, effective temperature, Roche-lobe filling factors, mass ratio, and orbital inclination of CoRoT 105895502 and analyze the temporal behavior of starspots in the system. Our analysis shows one comparably short-lived (≈40 d) starspot, remaining quasi-stationary in the binary frame, and one starspot showing prograde motion at a rate of 2.3° day−1, whose lifetime exceeds the duration of the observation. In the CoRoT band, starspots account for as much as 0.6% of the quadrature flux of CoRoT 105895502, however we cannot attribute the spots to individual binary components with certainty. Our findings can be explained by differential rotation, asynchronous stellar rotation, or systematic spot evolution.

scholarly journals Correspondances Entre Une Theorie Generale Planetaire En Variables Elliptiques Et La Theorie Classique De Le Verrier

1978 ◽  
Vol 41 ◽  
pp. 15-32 ◽  
Author(s):  
L. Duriez
Keyword(s):  
General Theory ◽  
Classical Theory ◽  
Major Axis ◽  
Second Order ◽  
Semi Major Axis ◽  
First Order ◽  
Short Period ◽  
The Masses ◽  
Secular Terms

AbstractIn order to improve the determination of the mixed terms in classical theories, we show how these terms may be derived from a general theory developed with the same variables (of a keplerian nature). We find that the general theory of the first order in the masses already allows us to develop the mixed terms which appear at the second order in the classical theory. We also show that a part of the constant perturbation of the semi-major axis introduced in the classical theory is present in the general theory as very long-period terms; by developing these terms in powers of time, they would be equivalent to the appearance of very small secular terms (in t, t2, …) in the perturbation of the semi-major axes from the second order in the masses. The short period terms of the classical theory are found the same in the general theory, but without the numerical substitution of the values of the variables.

scholarly journals 2MASS J10274572+0629104: the very short period young M6 dwarf binary system identified in K2 data

2019 ◽  
Vol 486 (3) ◽  
pp. 4144-4148
Author(s):  
R R Paudel ◽  
J E Gizis ◽  
A J Burgasser ◽  
C Hsu
Keyword(s):  
Infrared Spectroscopy ◽  
Binary System ◽  
Light Curve ◽  
Near Infrared ◽  
Rotation Periods ◽  
Beat Pattern ◽  
Short Period ◽  
Low Mass ◽  
Periodic Signals ◽  
Gaia Dr2

ABSTRACT We report the identification of a very low mass new binary system 2MASS J10274572+0629104, based on Kepler K2 photometry and Gaia DR2 astrometry. It is located at a distance of 90.0 ± 2.9 pc. The K2 light curve is consistent with a beat pattern of two periodic signals, and using Lomb–Scargle periodogram, we find two rotation periods of 0.2114 ± 0.0002 and 0.2199 ± 0.0003 d. We conclude that these rotation periods arise from two stars with similar spectral types of M6, and have nearly equal luminosity. It is the first ultracool binary system to be identified based on beat patterns in the light curve. Near-infrared spectroscopy yields RV = −9.8 ± 0.6 km s−1, v sin i = 21.5 ± 1.1 km s−1, Teff = 3110 ± 40 K, and log g = 5.2 ± 0.2. The motions are consistent with a young age, as are the rotation periods, but the source does not appear to be part of any known moving group. Furthermore, we detected three strong white light flares in the K2 light curve, with estimated total (UV/optical/IR) energies of 2.6 × 1033, 5.0 × 1033, and 3.5 × 1033 erg, respectively.

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