The determination of white dwarf parameters in dwarf novae by optical spectral modeling

• Published in: Research in astronomy and astrophysics Vol. 21; no. 7; pp. 158 - 40
• Main Authors: Andreevna Dudnik, Anastasiya, Alekseevna Mitrofanova, Arina, Vladimirovich Shimansky, Vladislav, Vladimirovich Borisov, Nikolay, Abdullovich Sakhibullin, Nail
• Format: Journal Article
• Language: English
• Published: Beijing National Astronomical Observatories, CAS and IOP Publishing Ltd 01.08.2021; IOP Publishing; Special Astrophysical Observatory,Russian Academy of Science,Nizhnii Arkhys,Karachai-Cherkessian Republic,Russia; Kazan (Volga Region) Federal University,Kazan,Republic of Tatarstan,Russia%Special Astrophysical Observatory,Russian Academy of Science,Nizhnii Arkhys,Karachai-Cherkessian Republic,Russia%Kazan (Volga Region) Federal University,Kazan,Republic of Tatarstan,Russia
• Subjects: Atmosphere; Atmospheric models; Dwarf novae; Hydrogen; Modelling; Novae; Parameters; Radiation; Spectra; stars: individual: FL Psc; stars: individual: TY Psc; stars: individual: V455 And; stars: variables: dwarf novae; Stellar atmospheres; techniques: spectroscopic; White dwarf stars; stars:variables:dwarf novae; stars:individual:FL Psc; techniques:spectroscopic; stars:individual:TY Psc; stars:individual:V455 And
• ISSN: 1674-4527
• DOI: 10.1088/1674-4527/21/7/158

Abstract This paper presents the results of a model analysis of optical spectra and determination of the parameters of three individual SU UMa and WZ Sge type dwarf novae. The moderate resolution spectra of TY Psc, FL Psc and V455 And were obtained at the 6-m BTA of the SAO RAS in the low state of these systems with the determination of white dwarf radiation. The theoretical spectra were calculated using the grid models of hydrogen dwarf atmospheres of white dwarfs by varying the parameters ( T eff and log g ) to reach the best agreement with the observed ones. We highlight different effects of the parameters on the shape and intensity of the HI lines. Therefore, it is possible to unambiguously determine T eff and log g from the analysis of observations. The fundamental parameters of white dwarfs ( M and R ) were found by comparing the parameters of atmospheres with theoretical models of the internal structure. The obtained parameters of the primaries of TY Psc, FL Psc and V455 And are consistent with the average values for SU UMa and WZ Sge systems. As a result, we demonstrate the efficiency of the method for determining the parameters of such systems based on the analysis of a limited set of observed optical spectra.