A complete astrophysical and dynamical study of the close visual binary system (CVBS) Finsen 350 (A7V + F0V), is presented. Beginning with the entire observational spectral energy distribution (SED) and the magnitude difference between the subcomponents, Al-Wardat’s complex method for analyzing CVBS was applied as a reverse method of building the individual and entire synthetic SEDs of the system. This was combined with Docobo’s analytic method to calculate the new orbits. Although possible short (approximately 9 years) and long period (of about 18 years) orbits could be considered taking into account the similar results of the stellar masses obtained for each of them (3.07 and 3.41 M_⊙, respectively), we confirmed that the short solution is correct. In addition, other physical, geometrical and dynamical parameters of this system such as the effective temperatures, surface gravity accelerations, absolute magnitudes, radii, the dynamical parallax, etc., are reported. The Main Sequence phase of both components with age around 0.79 Gyr is approved.

We present the complete set of atmospheric and fundamental parameters, in addition to the masses, for the individual components of eight stellar systems. The list of the systems, whose orbital solutions were published recently, includes seven binaries (HIP 14524, HIP 16025, HIP 46199, HIP 47791, HIP 60444, HIP 61100, HIP 73085) and one triple system (HIP 28671). The systems were analyzed using a spectrophotometric computational technique known as Al-Wardats method for analyzing binary and multiple stellar systems, which makes use of ATLAS9 line-blanketed plane-parallel model atmospheres. Using these estimated parameters, the positions of the components were located on the Hertzsprung–Russell diagram, evolutionary tracks and isochrones to estimate their ages, the range depending on the uncertainties in their metallicities. Five systems were found to be pre-main-sequence stars (HIP 14524, HIP 46199, HIP 60444, HIP 61100, HIP 73085), two were main-sequence stars (the zero-age HIP 28671 and the 6.3 Gyr HIP 16025), and one is a subgiant system (HIP 47791) with an age of 1.4 Gyr. Fragmentation is proposed as the most probable formation process for the eight systems. A comparison between the estimated masses and the dynamical ones lead to new dynamical parallaxes for four systems: (28.63 ± 0.56) mas for HIP 14524, (15.6 ± 0.63) mas for HIP 16025, (9.73 ± 0.26) mas for HIP 47791, and (16.53 ± 0.59) mas for HIP 73085. Hence, the orbital solutions were reclassified. We conclude that Gaia DR3 parallaxes are more precise than those given by Gaia DR2 and Hipparcos 2.

Binary stars are a very important source of astronomical information. Those short-period binaries observed by means of both spectroscopy and interferometry can provide, through their corresponding orbits, precise values regarding individual masses as well as orbital parallaxes. For this reason, it is fundamental to attempt to optically resolve double-lined spectroscopic binaries. In the present article, we used the elaboration of a specific algorithm in order to determine the necessary telescope aperture to resolve a concrete spectroscopic binary. To that end, using available photometric and spectroscopic information, we established a 3D model for each spectroscopic binary with an orbit from which we deduced the most probable maximum and minimum separations between the components. In this manner, using the obtained calibrations in our study, we also deduced different physical parameters of the components of each system. The methodology presented here was tested satisfactorily with a list of spectroscopic binaries that had been optically resolved and that have both the spectroscopic and visual orbits.

We illustrate the evolution of the peculiar behavior of the high mass X-ray binary GX 301-2, through the wind accretion model. We found that the donor of this system has 43 M⨀ and clearly it experienced of a mass exchange. As a result, the low terminal velocity of the wind from donor (1200 km/s), slow rotation and the relatively low luminosity (3.1×10³⁵erg/s), can easily fed the neutron star via the stellar wind with enough accretion matter. This will lead to explain the observed X-rays. It has been shown that the characteristics of mass-loss rate through stellar winds would reasonably be expected to alter the changes in wind velocity by X-rays.

During the last decades, searching for extrasolar planets was growing rapidly, and about 3869 exoplanets were discovered using various detection methods. In this work, we present a statistical analysis for these known exoplanets up to date provided by NASA Exoplanet Archive. In addition, we classify them depending on the type of the host stars' type; single star, and binary or multiple systems. Focusing on the exoplanets in binary system, we determine the common type of the stability orbit of the host binary system, and the probable mass ratio of the system to host a minimum one exoplanets. Moreover, we clarify the number of the companion planets for different systems.

This paper examines advances in ultra-high concentration photovoltaics (UHCPV), focusing specifically on vertical multijunction (VMJ) solar cells. The use of gallium arsenide (GaAs) in these cells increases their efficiency in a range of applications, including terrestrial and space settings. Several multijunction structures are designed to maximize conversion efficiency, including a vertical tunnel junction, which minimizes resistive losses at high concentration levels compared with standard designs. Therefore, careful optimization of interconnect layers in terms of thickness and doping concentration is needed. Homo-multijunction GaAs solar cells have been simulated and analyzed by using ATLAS Silvaco 5.36 R, a sophisticated technology computer-aided design (TCAD) tool aimed to ensure the reliability of simulation by targeting a high conversion efficiency and a good fill factor for our proposed structure model. Several design parameters, such as the dimensional cell structure, doping density, and sun concentrations, have been analyzed to improve device performance under direct air mass conditions AM1.5D. The optimized conversion efficiency of 30.2% has been achieved with investigated GaAs solar cell configuration at maximum concentration levels.