Time-Dependent Variations of Accretion Disk
In dward nova we assume the primary star as a white dwarf and the secondary as the late type star which filled Roche lobe. Mass flow from the secondary star leads to the formation of thin accretion disk around the white dwarf. We use the α parameter as viscosity to maintain the disk form and propose...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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The Korean Space Science Society
1987-06-01
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| Series: | Journal of Astronomy and Space Sciences |
| Online Access: | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/1987/v4n1/OJOOBS_1987_v4n1_11.pdf |
| _version_ | 1827361995012177920 |
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| author | Hye-Weon Na Kyung-Mee Kim Kyu-Hong Choi |
| author_facet | Hye-Weon Na Kyung-Mee Kim Kyu-Hong Choi |
| author_sort | Hye-Weon Na |
| collection | DOAJ |
| description | In dward nova we assume the primary star as a white dwarf and the secondary as the late type star which filled Roche lobe. Mass flow from the secondary star leads to the formation of thin accretion disk around the white dwarf. We use the α parameter as viscosity to maintain the disk form and propose that the outburst in dwarf nova cause the steep increase of source term. With these assumptions we solve the basic equations of stellar structure using Newton-Raphson method. We show the physical parameters like temperature, density, pressure, opacity, surface density, height and flux to the radius of disk. Changing the value of α, we compare several parameters when mass flow rate is constant with those of when luminosity of disk is brightest. At the same time, we obtain time-dependent variations of luminosity and mass of disk. We propose the suitable range of α is 0.15-0.18 to the difference of luminosity. We compare several parameters of disk with those of the normal late type stars which have the same molecular weight of disk is lower. Maybe the outburst in dwarf nova is due to the variation of the α value instead of increment of mass flow from the secondary star. |
| first_indexed | 2024-03-08T07:17:34Z |
| format | Article |
| id | doaj.art-7ecbb92d0d2a4896a5f26afd659fbd4e |
| institution | Directory Open Access Journal |
| issn | 2093-5587 2093-1409 |
| language | English |
| last_indexed | 2024-03-08T07:17:34Z |
| publishDate | 1987-06-01 |
| publisher | The Korean Space Science Society |
| record_format | Article |
| series | Journal of Astronomy and Space Sciences |
| spelling | doaj.art-7ecbb92d0d2a4896a5f26afd659fbd4e2024-02-03T00:27:37ZengThe Korean Space Science SocietyJournal of Astronomy and Space Sciences2093-55872093-14091987-06-01411123Time-Dependent Variations of Accretion DiskHye-Weon Na0Kyung-Mee Kim1Kyu-Hong Choi2Department of Astronomy and Meteorology, Yonsei UniversityDepartment of Astronomy and Meteorology, Yonsei UniversityDepartment of Astronomy and Meteorology, Yonsei UniversityIn dward nova we assume the primary star as a white dwarf and the secondary as the late type star which filled Roche lobe. Mass flow from the secondary star leads to the formation of thin accretion disk around the white dwarf. We use the α parameter as viscosity to maintain the disk form and propose that the outburst in dwarf nova cause the steep increase of source term. With these assumptions we solve the basic equations of stellar structure using Newton-Raphson method. We show the physical parameters like temperature, density, pressure, opacity, surface density, height and flux to the radius of disk. Changing the value of α, we compare several parameters when mass flow rate is constant with those of when luminosity of disk is brightest. At the same time, we obtain time-dependent variations of luminosity and mass of disk. We propose the suitable range of α is 0.15-0.18 to the difference of luminosity. We compare several parameters of disk with those of the normal late type stars which have the same molecular weight of disk is lower. Maybe the outburst in dwarf nova is due to the variation of the α value instead of increment of mass flow from the secondary star.http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/1987/v4n1/OJOOBS_1987_v4n1_11.pdf |
| spellingShingle | Hye-Weon Na Kyung-Mee Kim Kyu-Hong Choi Time-Dependent Variations of Accretion Disk Journal of Astronomy and Space Sciences |
| title | Time-Dependent Variations of Accretion Disk |
| title_full | Time-Dependent Variations of Accretion Disk |
| title_fullStr | Time-Dependent Variations of Accretion Disk |
| title_full_unstemmed | Time-Dependent Variations of Accretion Disk |
| title_short | Time-Dependent Variations of Accretion Disk |
| title_sort | time dependent variations of accretion disk |
| url | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/1987/v4n1/OJOOBS_1987_v4n1_11.pdf |
| work_keys_str_mv | AT hyeweonna timedependentvariationsofaccretiondisk AT kyungmeekim timedependentvariationsofaccretiondisk AT kyuhongchoi timedependentvariationsofaccretiondisk |