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Modified Masses and Parallaxes of Close Binary Systems: HD 39438

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Research in Astronomy and Astrophysics 2023年第11期23卷 31-37页

作者： Suhail Masda ZTYousef mashhoor al-wardat Awni al-Khasawneh Department of Physics Mahrah UniversityMahrahYemen Department of Physics Hadhramout UniversityMukallaYemen Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Department of Applied Physics and Astronomy and Sharjah Academy for AstronomySpace Sciences and TechnologyUniversity of SharjahP.O.Box 27272 SharjahUnited Arab Emirates Department of Physics Al al-Bayt UniversityMafraq 25113Jordan

We present the detailed fundamental stellar parameters of the close visual binary system HD 39438 for the first time. We used al-wardat's method for analyzing binary and multiple stellar systems. The method implements Kurucz's plane parallel model atmospheres to construct synthetic spectral energy distributions(SEDs) for both components of the system. It then combines the results of the spectroscopic analysis with the photometric analysis and compares them with the observed ones to construct the best synthetic SED for the combined system. The analysis gives the precise fundamental parameters of the individual components of the system. Based on the positions of the components of HD 39438 on the H-R diagram, and evolutionary and isochrone tracks, we found that the system belongs to the main sequence stars with masses of 1.24 and 0.98 solar masses for the components A and B, respectively, and age of 1.995 Gyr for both components. The main result of HD 39438 is new dynamical parallax, which is estimated to be 16.689 ± 0.03 mas.

关键词： methods:analytical techniques:photometric (stars:)binaries:visual techniques:spectroscopic

Physical and geometrical parameters of VCBS XIII: HIP 105947

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Research in Astronomy and Astrophysics 2018年第6期18卷 109-120页

作者： Suhail Gumaan Masda mashhoor Ahmed al-wardat Jiyaulla Khan Moula Khan Pathan Physics Department Dr. Babasaheb Ambedkar Marathwada University Aurangabad-431001 Maharashtra India Physics Department Hadhramout University PO Box 50511 Mukalla Yemen Dept. of Physics and Institute of Astronomy and Space Sciences A1 al-Bayt University PO Box 130040 Mafraq25113 Jordan Physics Department Maulana Azad College Aurangabad-431001 Maharashtra India

The best physical and geometrical parameters of the main sequence close visual binary system(CVBS), HIP 105947, are presented. These parameters have been constructed conclusively using al-wardat’s complex method for analyzing CVBSs, which is a method for constructing a synthetic spectral energy distribution(SED) for the entire binary system using individual SEDs for each component star. The model atmospheres are in its turn built using the Kurucz(ATLAS9) line-blanketed plane-parallel models. At the same time, the orbital parameters for the system are calculated using Tokovinin’s dynamical method for constructing the best orbits of an interferometric binary system. Moreover, the mass-sum of the components, as well as the ?θ and ?ρ residuals for the system, is introduced. The combination of al-wardat’s and Tokovinin’s methods yields the best estimations of the physical and geometrical parameters. The positions of the components in the system on the evolutionary tracks and isochrones are plotted and the formation and evolution of the system are discussed.

关键词： binaries: close binaries: visual stars: fundamental parameters stars: individual(HIP 105947)

Physical and geometrical parameters of CVBS X:the spectroscopic binary Gliese 762.1

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Research in Astronomy and Astrophysics 2016年第7期16卷 105-112页

作者： Suhail G.Masda mashhoor A.al-wardat Ralph Neuh user Hamid M.al-Naimiy Astrophysikalisches Institut und Universitats-Sternwarte Jena FSU Jena07745 JenaGermany Physics Department Faculty of ScienceAl al-Bayt UniversityPO Box:130040Mafraq25113 Jordan Applied Physics and Space Science Department University of Sharjah PO Box:27272 SharjahUnited Arab Emirates

We present the physical and geometrical parameters of the individual components of the close visual double-lined spectroscopic binary system Gliese 762.1, which were estimated using al-wardat＇s complex method for analyzing close visual binary systems. The estimated parameters of the individual components of the system are as follows： radius RA= 0.845±0.09R⊙, RB= 0.795±0.10R⊙, effective temperature Teff^A = 5300luminosity±50 K, Teff^B= 5150 L±50 K, surface gravity log gA= 4.52±0.10, log gB=4.54±0.15 and A= 0.51 with a semi-major axis of 0.0865±0.08L⊙, LB= 0.40±0.07L⊙. New orbital elements are presented±0.010 arcsec using the Hippracos parallax π = 58.96 ndividual masses of the system are determined as M = 1.±0.65 mas, and an accurate total mass and i72±0.60 M⊙,MA= 0.89±0.08 M⊙and MB= 0.83 K0 V and±0.07 M⊙. Finally, the spectral types and luminosity classes of both components are assigned as K1.5V for the primary and secondary components respectively,and their positions on the H-R diagram and evolutionary tracks are given.

关键词： stars fundamental parameters binaries spectroscopic binary system atmospheres modeling Gliese 762 1

Physical and geometrical parameters of CVBS XIV:the two nearby systems HIP 19206 and HIP 84425

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Research in Astronomy and Astrophysics 2021年第7期21卷 62-70页

作者： mashhoor A.al-wardat Enas Abu-alrob Abdallah M.Hussein Mohammad K.Mardini ali A.Taani Hatem S.Widyan Zahraa T.Yousef Hamid M.al-Naimiy Nihad A.Yusuf Department of Applied Physics and Astronomy University of SharjahSharjahUAE Sharjah Academy for Astronomy Space Science and TechnologySharjahUAE Department of Physics Al al-Bayt UniversityMafraq25113 Jordan Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Physics Department Faculty of ScienceAl-Balqa Applied University19117 SaltJordan Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Department of Physics Yarmouk UniversityIrbid21163Jordan

Data release 2(DR2) from the Gaia mission was of great help in precise determination of fundamental parameters of Close Visual Binary and Multiple Systems(CVBMSs), especially masses of their components, which are crucial parameters in understanding formation and evolution of stars and galaxies. This article presents the complete set of fundamental parameters for two nearby close visual binary systems(CVBSs), which are HIP 19206 and HIP 84425. We utilised a combination of two methods;the first one is Tokovinin's dynamical method to solve the orbit of the system and to estimate orbital elements and the dynamical mass sum, and the second one is al-wardat's method for analysing CVBMSs to estimate the physical parameters of the individual components. The latest method employs grids of Kurucz lineblanketed plane parallel model atmospheres to build synthetic Spectral Energy Distributions(SEDs) of the individual components. Trigonometric parallax measurements given by Gaia DR2 and Hipparcos catalogues are used to analyse the two systems. The difference in these measurements yielded slight discrepancies in the fundamental parameters of the individual components, especially masses. So, a new dynamical parallax is suggested in this work based on the most convenient mass sum as given by each of the two methods. The new dynamical parallax for the system HIP 19205 of 22.97±0.95 mas coincides well with the trigonometric one reported recently(in December 2020) by Gaia EDR3 of 22.3689 ± 0.4056 mas. The positions of the components of the two systems on the evolutionary tracks and isochrones are plotted, which suggest that all components are solar-type main sequence stars. Their most probable formation and evolution scenarios are also discussed.

关键词： binaries:close binaries:visual-stars:fundamental parameters stars:individual:HIP 19206 and HIP 84425

The stellar system HIP 101227:is it a binary,a triple or a quadruple system?

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Research in Astronomy and Astrophysics 2021年第5期21卷 121-129页

作者： Zahra Talal Yousef Adlyka Annuar Abdallah Mohammad Hussein Hamid al-Naimiy mashhooral-wardat Nurul Shazana Abdul Hamid Mohammed Fadil Talafha Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Department of Physics Al al-Bayt UniversityMafraq 25113Jordan Department of Applied Physics and Astronomy University of SharjahP.O.Box 27272 SharjahUnited Arab Emirates Sharjah Academy for Astronomy Space Sciences and Technology SAASSTUniversity of SharjahP.O.Box 27272 SharjahUnited Arab Emirates

In this paper,we present the analysis of the stellar system HIP 101227 to determine the actual number of components in the system,and their *** use dynamical modeling and complex spectrophotometric(involving atmospheric modeling)techniques with recent data,to determine the physical properties and orbital solution for the system,respectively,with better accuracy than past *** on our analysis,we found that the system is more consistent with being a quadruple rather than a binary or a triple system as suggested by previous *** total mass of the system determined from our SED analysis is 3.42±0.20 M,which is distributed almost equally between the four *** stars are found to be zero-age main sequence stars;i.e.,at the last stage of pre-main sequence,with age less than 200 Myr and spectral types *** four stars have very similar physical characteristics,suggesting that the fragmentation process is the most likely theory for the formation and evolution of the system.

关键词： stars:binaries:close stars:binaries:visual stars:individual:HIP 101227

Orbital and physical parameters of the close binary system GJ 9830(HIP 116259)

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Research in Astronomy and Astrophysics 2019年第7期19卷 163-172页

作者： Suhail G.Masda mashhoor A.al-wardat J.M.Pathan Physics Department Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad-431001MaharashtraIndia Physics Department Hadhramout UniversityPO Box: 50511MukallaYemen Physics Department Al al-Bayt UniversityPO Box: 130040Mafraq25113 Jordan Physics Department Maulana Azad CollegeAurangabad-431001MaharashtraIndia

We present the complete set of physical and geometrical parameters of the visual close binary system GJ 9830 for the first time by applying al-wardat’s complex *** method combines magnitude difference from speckle interferometry,synthetic spectral energy distributions of the binary components which are constructed based on grids of Kurucz blanketed models(ATLAS9),and the orbital solution using Tokovinin’s dynamical method to estimate the parameters of individual *** analysis of the system by employing synthetic photometry resulted in the following set of parameters:Teff= 6220 ± 100 K,log g = 4.30 ± 0.12,R = 1.10 ± 0.08 R⊙for the primary component and Teff= 4870 ± 100 K,log g = 4.60 ± 0.11,R = 0.709 ± 0.07 R⊙for the secondary *** recently published dynamical parallax from the Gaia space mission was used to calculate the total mass of the binary system as 1.75 ± 0.06 M⊙,which coincides with those estimated using al-wardat’s method as MA= 1.18 ± 0.10 M⊙,MB= 0.75 ± 0.08 M⊙.The analysis of the system reveals that both components are characteristic of main sequence stars and have an age of around 1.4 ± 0.50 *** evolutionary tracks and isochrones of the system’s components are discussed,and the fragmentation process is suggested as the most likely process for the formation of the system.

关键词： binaries close-binaries visual-stars fundamental parameters-technique synthetic photometry-stars individual GJ 9830

Physical and geometrical parameters of CVBS Ⅺ: Cou 1511(HIP 12552)

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Research in Astronomy and Astrophysics 2016年第11期16卷 13-18页

作者： mashhoor A. al-wardat Mohammad H. El-Mahameed Nihad A. Yusuf Awni M. Khasawneh Suhail G. Masda Physics Department A1 al-Bayt University PO Box: 130040 Mafraq 25113 Jordan Department of Physics A1-Hussein Bin Talal University Maan 71111 Jordan Department of Physics Yarmouk University Irbid 21163 Jordan King Abdullah I School for Graduate Studies and Scientific Research Princess Sumaya University for Technology PO Box 1438 Amman 11941 Jordan Royal Jordanian Geographic Center Amman 11941 Jordan Astrophysikalisches Institut und Universitaits-Sternwarte Jena FSU Jena 07745 Jena Germany

Model atmospheres of the close visual binary star Cou 1511 （HIP 12552） are constructed using grids of Kuruz＇s blanketed models to build the individual synthetic spectral energy distributions （SEDs） for both components. These synthetic SEDs are combined together for the entire system and compared with the observational one following A1-wardat＇s complex method for analyzing close visual binary stars. The entire observational SED of the system is used as a reference for comparison between the synthetic SED and the observed one. The parameters of both components are derived as： Teff = 6180 4- 50 K, Tebfr = 5865 ＋ 70 K, log 9a = 4.35 ± 0.12, log 9b = 4.45± 0.14, Ra = 1.262 ± 0.08 R⊙^eff, Rb = 1.006 ± 0.07 R⊙^ett, La = 2.09 -4- 0.10 L⊙ and Lb = 1.08 ± 0.12 L⊙, with spectral types F8V and G1.5V for components （a, b） respectively and age of 3.0 ± 0.9 Gyr. A modified orbit of the system is built and the masses of the two components are calculated as Ma = 1.17 ±0.11 Me and Mb = 1.06 ± 0.10 Me.

关键词： binaries -- visual stars -- fundamental parameters stars -- Cou 1511 (Hip 12552)

On the possibility of disk-fed formation in supergiant high-mass X-ray binaries

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Research in Astronomy and Astrophysics 2019年第1期19卷 123-130页

作者： ali Taani Shigeyuki Karino Liming Song mashhoor al-wardat Awni Khasawneh Mohammad K.Mardini Physics Department Faculty of ScienceAl-Balqa Applied University Faculty of Science and Engineering Kyushu Sangyo University Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences Department of Physics Al al-Bayt University Royal Jordanian Geographic Center Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences

We consider the existence of a neutron star magnetic field by the detected cyclotron lines. We collected data on nine sources of high-mass X-ray binaries with supergiant companions as a test case for our model, to demonstrate their distribution and evolution. The wind velocity, spin period and magnetic field strength are studied under different mass loss rates. In our model, correlations between mass-loss rate and wind velocity are found and can be tested in further observations. We examine the parameter space where wind accretion is allowed, avoiding the barrier of rotating magnetic fields, with robust data on the magnetic field of neutron stars. Our model shows that most sources(six of nine systems) can be fed by the wind with relatively slow velocity, and this result is consistent with previous predictions. In a few sources,our model cannot fit the standard wind accretion scenario. In these peculiar cases, other scenarios(disk formation, partial Roche lobe overflow) should be considered. This would provide information about the evolutionary tracks of various types of binaries, and thus exhibit a clear dichotomy behavior in wind-fed X-ray binary systems.

关键词： binaries:X-rays stars:neutron stars:fundamental parameters accretion disks formation magnetic fields

Characterization of the molecular dysfunctions occurring in Aicardi-Goutieres syndrome patients with mutations in ADAR1

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Genes & Diseases 2024年第3期11卷 116-119页

作者： Sofan al wardat Loredana Frasinlli Elisa Orecchini Federica Rey Silvia Anna Ciafre Silvia Galardi Jessica Garau Stella Gagliardi Simona Orcesi Davide Tonduti Stephana Carelli Cristina Cereda Ernesto Picardi alessandro Michienzi Department of Biomedicine and Prevention University of Rome Tor VergataRome 00133Italy Pediatric Clinical Research Center"Romeo ed Enrica Invernizzi" Department of Biomedical and Clinical SciencesUniversity of MilanoMilano 20157Italy Center of Functional Genomics and Rare Diseases Department of PediatricsBuzzi Children's HospitalMilano20154Italy Department of Child Neurology and Psychiatry IRccs Mondino FoundationPavia 27100Italy Unit of Pediatric Neurology C.O.A.L.A(Center for Diagnosis and Treatment of Leukodystrophies)Buzzi Children's HospitalMilano 20154Italy Department of Biosciences Biotechnologies and EnvironmentUniversityof Bari"AldoMoro"Bari 70125Italy Institute of Biomembranes Bioenergetics and Molecular Biotechnologies(IBIOM)National Research Council(CNR)Bari 70126Italy Biostructures and Biosystems National Institute(INBB) Rome00136Italy Institute of Biochemistry and Cell Biology IBBC-CNRCampus Adriano Buzzati TraversoRome 00015Italy

Aicardi-Goutieres syndrome(AGS)is a systemic inflammatory disorder caused by mutations in any one of the nine different genes,whose deficiency provokes a type I(interferon)IFN response probably central to pathogenesis.^(1) ADAR1,one of the genes mutated in AGS(AGS6),encodes for an enzyme that belongs to the ADAR family(ADAR1,ADAR2,and ADAR3)that catalyzes the conversion of adenosine to inosine within double-stranded RNAs(dsRNAs)(RNA editing A-to-1).

关键词： ADAR1 interferon res