WEKO3
アイテム
文献学的方法による恒星の長期間変動の探査
http://hdl.handle.net/10965/466
http://hdl.handle.net/10965/466619bec21-4ab5-4928-8856-7ecb46e7ffb1
| 名前 / ファイル | ライセンス | アクション |
|---|---|---|
AHSUSK_NSS_34_1.pdf (688.4 kB)
|
|
| Item type | 紀要論文 / Departmental Bulletin Paper(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2017-09-30 | |||||
| タイトル | ||||||
| タイトル | 文献学的方法による恒星の長期間変動の探査 | |||||
| 言語 | ja | |||||
| タイトル | ||||||
| タイトル | Survey of Long-term Stellar Variabilities | |||||
| 言語 | en | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| キーワード | ||||||
| 主題Scheme | Other | |||||
| 主題 | 変光星 | |||||
| キーワード | ||||||
| 主題Scheme | Other | |||||
| 主題 | 突発天体 | |||||
| キーワード | ||||||
| 主題Scheme | Other | |||||
| 主題 | 歴史的星表 | |||||
| キーワード | ||||||
| 主題Scheme | Other | |||||
| 主題 | 恒星の等級 | |||||
| キーワード | ||||||
| 主題Scheme | Other | |||||
| 主題 | 測光 | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | variable stars | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | transient objects | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | historical star catalogues | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | stellar magnitude | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | photometry | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||
| 資源タイプ | departmental bulletin paper | |||||
| 著者 |
藤原, 智子
× 藤原, 智子 |
|||||
| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | The comparison of visual magnitudes of stars recorded in historical star catalogues is expected to yield information about their long-term magnitude variations over ∼2000 years. Considering the epoch when the first systematic and accurate observations of fixed stars were catalogued, stars with long-term of the order of 100, 1000 or more years variability have not been found yet. However it is still possible that there are stars with longer timescales than 100 years variability. First, by comparison of seven old catalogues including 2123 sampled stars, the independence of stellar magnitude catalogues is demonstrated. Furthermore, comparing them with a modern star catalogue, one can see that the magnitude differences show a Gaussian distribution. If they are sufficiently larger than the deduced standard deviations, magnitude variations between catalogues can be considered real. Essentially, the stellar magnitudes compiled in old works can be used as scientific data within the average intrinsic uncertainty. These seven old catalogues can be used as data for the survey of the long-term variability of stars. Second, we investigate magnitude systems in these historical star catalogues. We put all data set on Pogson’s logarithmic and the power-law scale suggested by those believed that human’s sensitivities were on a power-law scale, and verify that magnitude systems fit logarithmic scale and that light ratios also correspond to that of Pogson. Third, we find that through 2123 data sets of stellar magnitude, most of stars recorded in old star catalogues show little or no variation. The number of stars with magnitude variation larger than 3 mag during these ∼ 2000 years reaches 8. Especially, α Sgr shows the largest variation of 3.91 mag. Comparing the magnitude of this object with those of stars in the neighborhood, nearby stars show very small or no variation. Therefore, it could be considered that the magnitude of α Sgr has not changed due to the observational condition. There is no reason to change the magnitude because this object is one of the main-sequence stars on the HR diagram and not consists of binary system. We carried out to find a candidate of long-term variability stars undiscovered and whose mechanism has not been explained. |
|||||
| 内容記述 | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | 1. General introduction 2. Astronomical photometry 2.1. Historical review on astronomical phenomena records 2.2. Naked-eye visual magnitude estimates and their systems 2.3. Characteristics of old catalogues 2.3.1. Almagest 2.3.2. Kitāb Şuwar al-Kawākib 2.3.3. Ulugh Beg’s Catalogue of Stars 2.3.4. Astronomiae Instauratae Progymnasmata 2.3.5. Uranometria 2.3.6. Historia Coelestis Britannica 2.3.7. Uranometria Nova 3. Data selection and analysis 4. Results and discussion 4.1. Independence of catalogues 4.2. Consistency of magnitudes 4.3. Magnitude systems in old star catalogues 4.3.1. Verification of historical magnitudes 4.3.2. logarithm vs. power law 4.3.3. Examination of the light ratio 4.4. Candidates of stars with long-term variability 4.4.1. Stars with large magnitude variation 4.4.2. Astrophysical basic data 4.4.3. Magnitude variation of α Sgr 5. Concluding remarks Appendix A. Stellar structure and evolution and its time scale A.1. Basic equations A.1.1. Equation of continuity A.1.2. Equation of motion A.1.3. Energy conservation in stars A.1.4. Energy transfer A.1.5. Chemical evolution A.2. Timescales A.2.1. Dynamical time-scale A.2.2. Kelvin-Helmholtz time-scale (thermal time-scale) A.2.3. Nuclear time-scale A.3. Virial theorem B. Stages of stellar evolution B.1. Star formation B.2. Pre-main-sequence phase B.3. Main-sequence phase B.4. Helium burning B.4.1. Massive stars B.4.2. Low-mass stars B.5. Later phases B.6. Final explosions and collapse C. Magnitude data in old star catalogues References |
|||||
| 書誌情報 |
京都産業大学論集. 自然科学系列 巻 34, p. 1-125, 発行日 2005-03 |
|||||
| 出版者 | ||||||
| 出版者 | 京都産業大学 | |||||
| ISSN | ||||||
| 収録物識別子タイプ | PISSN | |||||
| 収録物識別子 | 1348-3323 | |||||
| 書誌レコードID | ||||||
| 収録物識別子タイプ | NCID | |||||
| 収録物識別子 | AA11923897 | |||||
| 著者版フラグ | ||||||
| 出版タイプ | VoR | |||||
| 出版タイプResource | http://purl.org/coar/version/c_970fb48d4fbd8a85 | |||||
