金牛座SZ
| 觀測資料 曆元 J2000.0 | |
|---|---|
| 星座 | 金牛座 |
| 星官 | |
| 赤經 | 04h 37m 14.778s[2] |
| 赤緯 | +18° 32′ 34.93″[2] |
| 視星等（V） | 6.39 to 6.69[3] |
| 特性 | |
| 演化阶段 | 超巨星 |
| 光谱分类 | F5Ib-F9.5Ib[4] |
| B−V 色指数 | 0.810+0.025 −[5] |
| 变星类型 | 仙王座δ[6] |
| 天体测定 | |
| 徑向速度 (Rv) | −1.2+0.2 −[7] km/s |
| 自行 (μ) | 赤经：−4.403 mas/yr 赤纬：−5.232 mas/yr |
| 视差 (π) | 1.5741 ± 0.028[2] mas |
| 距离 | 2,070 ± 40 ly (640 ± 10 pc) |
| 詳細資料 | |
| 質量 | 6.1+0.8 −[8] M☉ |
| 半徑 | 42.2+3.0 −[9] R☉ |
| 表面重力 (log g) | 2.0–2.2[10] |
| 亮度 | 1,905[11] L☉ |
| 溫度 | 6,015–6,420[11] K |
| 金属量 [Fe/H] | 0.08[10] dex |
| 年齡 | 69–80[12] Myr |
| 其他命名 | |
| 參考資料庫 | |
| SIMBAD | 资料 |
金牛座SZ是位於黃道星座金牛座的一顆變星。這顆恆星的亮度接近肉眼可見的下限，以3.149天的週期，在視星等6.39等到6.69星等之間變化[3]。根據視差的量測，到這顆恆星的距離約為2,070光年[2]。有迹象表明這可能是一顆聯星系統，但證據並不確定[14]。
這顆恆星的可變性是由卡爾·史瓦西（英語：Karl Schwarzschild）在1911年宣佈的，起初被命名為41.1910，週期為3.1484 d[15][16]。勒維特（英語：Henrietta Swan Leavitt）將這項研究持續到1914年，產生了一個週期為3.1487 d的光變曲線[17]。1916年，H.沙普利（英語：Harlow Shapley）的一項光譜研究表明，造父變星的這種恆星脈動使恆星分類的類型沿著光變曲線變化，從光度最低的F7到最高的A9[18]。尤裏·尼古拉耶維奇·埃夫雷莫夫在1964年提出，這顆恆星位於疏散星團NGC 1647的東北方2.2°，可能是其暈成員[19]。然而，後來因為自行不能吻合而，因而引起爭議[20]。它在1985年被沃爾夫岡·吉倫確認為經典造父變星 [21]。
在變星總表中，金牛座SZ被歸類為DCEPS型的仙王座δ型變星，它顯示出一條幾乎對稱的小振幅光變曲線[6]。它在第一個泛音中脈動[19]，並且在演化方面，正在經歷第二次穿越造父變星的不穩定帶[12]。到1987年，已經觀察到金牛座SZ脈動週期的四次變化[22]；脈動頻率每年減少-0.49 秒[12]。這顆星的年齡大約是7,500萬年[12]，質量是太陽的6倍[8]，半徑是太陽的42倍[9]。恆星的有效溫度、半徑和光譜類型在每個脈動週期中都會變化[11]。
參考資料[编辑]
- ^ MAST: Barbara A. Mikulski Archive for Space Telescopes. Space Telescope Science Institute. [8 December 2021]. （原始内容存档于2023-03-27）.
- ^ 2.0 2.1 2.2 2.3 Brown, A. G. A.; et al. Gaia Early Data Release 3: Summary of the contents and survey properties. Astronomy & Astrophysics. 2021, 649: A1. Bibcode:2021A&A...649A...1G. S2CID 227254300. arXiv:2012.01533
. doi:10.1051/0004-6361/202039657 . 已忽略未知参数|collaboration=(帮助) (勘误: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR. - ^ 3.0 3.1 Klagyivik, P.; Szabados, L., Observational studies of Cepheid amplitudes. I. Period-amplitude relationships for Galactic Cepheids and interrelation of amplitudes, Astronomy and Astrophysics, September 2009, 504 (3): 959–972, Bibcode:2009A&A...504..959K, S2CID 18283579, arXiv:0908.3561 , doi:10.1051/0004-6361/200811464.
- ^ Kraft, Robert P., Color Excesses for Supergiants and Classical Cepheids. I. Calibration of the Gband Photometry, Astrophysical Journal, March 1960, 131: 330, Bibcode:1960ApJ...131..330K, doi:10.1086/146837.
- ^ Anderson, E.; Francis, Ch., XHIP: An extended hipparcos compilation, Astronomy Letters, 2012, 38 (5): 331, Bibcode:2012AstL...38..331A, S2CID 119257644, arXiv:1108.4971 , doi:10.1134/S1063773712050015.
- ^ 6.0 6.1 Samus', N. N; et al, General catalogue of variable stars, Astronomy Reports, GCVS 5.1, 2017, 61 (1): 80, Bibcode:2017ARep...61...80S, S2CID 125853869, doi:10.1134/S1063772917010085.
- ^ Gontcharov, G. A., Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system, Astronomy Letters, November 2006, 32 (11): 759–771, Bibcode:2006AstL...32..759G, S2CID 119231169, arXiv:1606.08053 , doi:10.1134/S1063773706110065.
- ^ 8.0 8.1 Marconi, Marcella; et al, Predicted Masses of Galactic Cepheids in the Gaia Data Release 2, The Astrophysical Journal Letters, July 2020, 898 (1): L7, Bibcode:2020ApJ...898L...7M, S2CID 220265392, arXiv:2006.16610 , doi:10.3847/2041-8213/aba12b, L7.
- ^ 9.0 9.1 Postma, Joseph E.; Milone, E. F., Observations and Analyses of the Cepheid SZ Tauri, Bulletin of the American Astronomical Society, June 2006, 38: 144, Bibcode:2006AAS...208.6506P.
- ^ 10.0 10.1 Andrievsky, S. M.; et al, Barium abundances in Cepheids, Monthly Notices of the Royal Astronomical Society, 2013, 428 (4): 3252, Bibcode:2013MNRAS.428.3252A, arXiv:1210.6211 , doi:10.1093/mnras/sts270 .
- ^ 11.0 11.1 11.2 Sanwal, B. B.; Rautela, B. S., Spectrophotometric Study of the Cepheids DT-Cygni and SZ-Tauri, Astrophysics and Space Science, January 1989, 151 (2): 209–215, Bibcode:1989Ap&SS.151..209S, S2CID 119557969, doi:10.1007/BF00648379.
- ^ 12.0 12.1 12.2 12.3 Fadeyev, Yu. A., Evolution, pulsation and period change in the Cepheid SZ Tau, Astronomy Letters, November 2015, 41 (11): 640–645, Bibcode:2015AstL...41..640F, S2CID 255192877, arXiv:1507.04715 , doi:10.1134/S1063773715110031.
- ^ SZ Tau. SIMBAD. 斯特拉斯堡天文資料中心.
- ^ Kervella, Pierre; et al, Multiplicity of Galactic Cepheids and RR Lyrae stars from Gaia DR2. II. Resolved common proper motion pairs, Astronomy & Astrophysics, March 2019, 623: 40, Bibcode:2019A&A...623A.117K, arXiv:1908.00545 , doi:10.1051/0004-6361/201834211, A117.
- ^ Schwarzschild, Karl, Über den Lichtwechsel des Veränderlichen 41.1910 Tauri, Astronomische Nachrichten, October 1911, 189 (20): 345–356 [2023-08-14], Bibcode:1911AN....189..345S, doi:10.1002/asna.2101892002, （原始内容存档于2023-08-14） （德语）.
- ^ Shapley, H., Concerning the ellipsoidal variables SZ Tauri and S Antliae, Astronomische Nachrichten, May 1913, 194 (21): 353–359 [2023-08-14], Bibcode:1913AN....194..353S, doi:10.1002/asna.19131942102, （原始内容存档于2023-08-14）.
- ^ Leavitt, Henrietta S.; Pickering, Edward C., Observations of SZ Tauri, Harvard College Observatory Circular, November 1914, 186: 1–4, Bibcode:1914HarCi.186....1L.
- ^ Shapley, H., The variations in spectral type of twenty Cepheid variables, Astrophysical Journal, December 1916, 44: 273–291, Bibcode:1916ApJ....44..273S, doi:10.1086/142295.
- ^ 19.0 19.1 Turner, David G., Galactic Clusters With Associated Cepheid Variables. III. NGC 1647 and SZ Tauri, Astronomical Journal, November 1992, 104: 1865 [2023-08-14], Bibcode:1992AJ....104.1865T, doi:10.1086/116363, （原始内容存档于2023-08-14）.
- ^ Baumgardt, H.; et al, Absolute proper motions of open clusters. I. Observational data, Astronomy and Astrophysics Supplement, October 2000, 146 (2): 251–258, Bibcode:2000A&AS..146..251B, S2CID 7180188, arXiv:astro-ph/0010306 , doi:10.1051/aas:2000362.
- ^ Gieren, W. P., Physical properties of the cepheids RT Aurigae and SZ Tauri, Astronomy and Astrophysics, July 1985, 148: 138–144, Bibcode:1985A&A...148..138G.
- ^ Trammell, Susan R., The Changing Period of SZ Tauri, The Journal of the American Association of Variable Star Observers, December 1987, 16 (2): 104–106, Bibcode:1987JAVSO..16..104T.
