NGC 2273
NGC 2273是一個位於天貓座的棒旋星系，距離地球約9500萬光年，由尼爾斯·克里斯托弗·杜奈爾於1867年9月15日發現 。根據它在天球中的大小，可以推測該星系的直徑約10萬光年。[3]
| NGC 2273 | |
|---|---|
 | |
| 觀測資料（J2000 曆元） | |
| 星座 | 天貓座 |
| 赤經 | 06h 50m 08.7s[1] |
| 赤緯 | 60° 50′ 45″[1] |
| 紅移 | 0.006138 ± 0.000013 [1] |
| 徑向速度 | 1,840 ± 4 km/s[1] |
| 距離 | 94.5 ± 13 Mly (29.0 ± 4.0 Mpc)[1] |
| 視星等 (V) | 11.6 [2] |
| 特徵 | |
| 類型 | SB(r)a [1] |
| 角直徑 (V) | 3′.2 × 2′.5[1] |
| 其他 | 塞弗特星系 |
| 其他名稱 | |
| UGC 3546、MCG+10-10-015、PGC 19688, Mrk 620[1] | |
特徵
編輯
NGC 2273有一個環星系，傾角為41 度，有由兩個螺旋臂構成一個內環和兩個外偽環，並有一個直徑40弧秒的星系棒。[4] 該星系擁有質量約1.1×109 M☉的氫氣（HI），大部分位於外偽環區域。該星系還擁有大量的分子氣體，如CO線所示，這說明恆星形成活動在該星系很活躍。[5]星系的總紅外光度為1010.25 L☉。[6]
哈勃空間望遠鏡對星系中心附近20弧秒區域的觀測顯示星系的螺旋臂與星系內環相對應。星系中心的卵狀結構由一個星系棒和兩個弧形的星系核環組成，它所造成的輻射與電離氫區有關。[7]核周圍有一個直徑7弧秒的環狀結構，其西北部分比較清晰，離星系核20弧秒處有另一個星環。[8]
星系核
編輯根據其光學頻譜中存在的譜線，NGC 2273具有活動星系核 ，並被分類為II型西佛星系。[9][10]此外，在星系中心還檢測到了水千脈澤。這可以由活動星系核或明顯的恆星形成活動而產生。[11]
BeppoSAX衛星、XMM-牛頓衛星和錢德拉X射線天文台猜測NGC 2273核心被柱密度較高的康普頓粗柱（Compton thick column）遮住，[12][13]ASCA估計其有1.1×1024 cm−2[14]，朱雀衛星估計其有1.5×1024 cm−2。[15]Fe-K線表明，硬X射線嘗試通過冷金屬物質時被反射。[14]星系核心區域的光譜有微弱的偏振，尤其是H-α線。[16]從NGC 2273發現的寬X射線光譜由熱的疏散的軟的部分、反射部分和能量集中部分組成。該星系2-10 keV的X射線通量估計為1.7×1042 ergs−1.[15]
該星系核有兩個相距170秒差距的相對論性噴流無線電波源發射線性無線電波。[17]在 [O III] λ5007的圖像中可以看到線型噴發物噴出的物質在核周圍已經擴展到2弧秒大小。它與無線電波發射源對齊，可能與星系核有關。[7]
關於活動星系核活動所需的能量來源，最廣為接受的猜想是星系中心超大質量黑洞的周圍存在一個吸積盤。基於水脈澤環核圓盤的運動，該星系中心黑洞質量約是(7.5±0.4)×106 M☉。該吸積盤還出現扭曲。[18]
附近的星系
編輯NGC 2273是NGC 2273星系群中最亮的星系。該星系群中還包括NGC 2237B 和UGC 3504，[19][20]其中NGC 2237B在南邊40弧秒處。[21]
另見
編輯參考
編輯- ^ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 NASA/IPAC Extragalactic Database. Results for NGC 2273. [2019-01-18]. （原始內容存檔於2021-07-24）.
- ^ Revised NGC Data for NGC 2273. spider.seds.org. [25 November 2018]. （原始內容存檔於2018-02-14）.
- ^ NGC 2273 （頁面存檔備份，存於互聯網檔案館） cseligman.com
- ^ Aguerri, J. A. L.; Beckman, J. E.; Prieto, M. Bar Strengths, Bar Lengths, and Corotation Radii, Derived Photometrically for 10 Barred Galaxies. The Astronomical Journal. November 1998, 116 (5): 2136–2153. Bibcode:1998AJ....116.2136A. doi:10.1086/300615
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- ^ van Driel, W.; Buta, R. J. A study of the ringed galaxies NGC2273, 4826, and 6217. I - H I line observations. Astronomy and Astrophysics. 1 May 1991, 245: 7–26. Bibcode:1991A&A...245....7V. ISSN 0004-6361.
- ^ Sanders, D. B.; Mazzarella, J. M.; Kim, D.-C.; Surace, J. A.; Soifer, B. T. The IRAS Revised Bright Galaxy Sample. The Astronomical Journal. October 2003, 126 (4): 1607–1664. Bibcode:2003AJ....126.1607S. S2CID 14825701. arXiv:astro-ph/0306263 . doi:10.1086/376841.
- ^ 7.0 7.1 Ferruit, Pierre; Wilson, Andrew S.; Mulchaey, John. Hubble Space Telescope WFPC2 Imaging of a Sample of Early-Type Seyfert Galaxies. The Astrophysical Journal Supplement Series. May 2000, 128 (1): 139–169. Bibcode:2000ApJS..128..139F. doi:10.1086/313379 .
- ^ Yankulova, I. M. The circumnuclear gas and dust environment of the ringed Seyfert 2 galaxy MKN 620. Astronomy and Astrophysics. 1 April 1999, 344: 36–42. Bibcode:1999A&A...344...36Y. ISSN 0004-6361.
- ^ Huchra, J. P.; Wyatt, W. F.; Davis, M. New bright Seyfert Galaxies. The Astronomical Journal. December 1982, 87: 1628. Bibcode:1982AJ.....87.1628H. doi:10.1086/113254.
- ^ Ho, Luis C.; Filippenko, Alexei V.; Sargent, Wallace L. W. A Search for "Dwarf Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies. The Astrophysical Journal Supplement Series. October 1997, 112 (2): 315–390. Bibcode:1997ApJS..112..315H. S2CID 17086638. arXiv:astro-ph/9704107 . doi:10.1086/313041.
- ^ Zhang, J. S.; Henkel, C.; Kadler, M.; Greenhill, L. J.; Nagar, N.; Wilson, A. S.; Braatz, J. A. Extragalactic H2O masers and X-ray absorbing column densities. Astronomy & Astrophysics. 19 April 2006, 450 (3): 933–944. Bibcode:2006A&A...450..933Z. doi:10.1051/0004-6361:20054138 .
- ^ Maiolino, R.; Salvati, M.; Bassani, L.; Dadina, M.; della Ceca, R.; Matt, G.; Risaliti, G.; Zamorani, G. Heavy obscuration in X-ray weak AGNs. Astronomy and Astrophysics. 1 October 1998, 338: 781–794. Bibcode:1998A&A...338..781M. ISSN 0004-6361. arXiv:astro-ph/9806055 .
- ^ Guainazzi, M.; Fabian, A. C.; Iwasawa, K.; Matt, G.; Fiore, F. On the transmission-dominated to reprocessing-dominated spectral state transitions in Seyfert 2 galaxies. Monthly Notices of the Royal Astronomical Society. 1 January 2005, 356 (1): 295–308. Bibcode:2005MNRAS.356..295G. arXiv:astro-ph/0409689 . doi:10.1111/j.1365-2966.2004.08448.x .
- ^ 14.0 14.1 Terashima, Yuichi; Iyomoto, Naoko; Ho, Luis C.; Ptak, Andrew F. X-Ray Properties of LINERs and Low-Luminosity Seyfert Galaxies Observed with ASCA. I. Observations and Results. The Astrophysical Journal Supplement Series. March 2002, 139 (1): 1–36. Bibcode:2002ApJS..139....1T. arXiv:astro-ph/0203005 . doi:10.1086/324373 .
- ^ 15.0 15.1 Awaki, Hisamitsu; Terashima, Yuichi; Higaki, Yuusuke; Fukazawa, Yasushi. Detection of Hard X-Rays from the Compton-Thick Seyfert 2 Galaxy NGC 2273 with Suzaku. Publications of the Astronomical Society of Japan. 30 January 2009, 61 (sp1): S317–S325. Bibcode:2009PASJ...61S.317A. S2CID 12846803. arXiv:0810.4570 . doi:10.1093/pasj/61.sp1.S317.
- ^ Moran, Edward C.; Barth, Aaron J.; Kay, Laura E.; Filippenko, Alexei V. The Frequency of Polarized Broad Emission Lines in Type 2 Seyfert Galaxies. The Astrophysical Journal. 10 September 2000, 540 (2): L73–L77. Bibcode:2000ApJ...540L..73M. arXiv:astro-ph/0007357 . doi:10.1086/312876 .
- ^ Ulvestad, J. S.; Wilson, A. S. Radio structures of Seyfert galaxies. VI - VLA observations of a nearby sample. The Astrophysical Journal. October 1984, 285: 439. Bibcode:1984ApJ...285..439U. doi:10.1086/162520.
- ^ Kuo, C. Y.; Braatz, J. A.; Condon, J. J.; Impellizzeri, C. M. V.; Lo, K. Y.; Zaw, I.; Schenker, M.; Henkel, C.; Reid, M. J.; Greene, J. E. The Megamaser Cosmology Project. III. Accurate Masses of Seven Supermassive Black Holes in Active Galaxies with Circumnuclear Megamaser Disks. The Astrophysical Journal. 20 January 2011, 727 (1): 20. Bibcode:2011ApJ...727...20K. arXiv:1008.2146 . doi:10.1088/0004-637X/727/1/20 .
- ^ Makarov, Dmitry; Karachentsev, Igor. Galaxy groups and clouds in the local (z∼ 0.01) Universe. Monthly Notices of the Royal Astronomical Society. 21 April 2011, 412 (4): 2498–2520 [2021-07-24]. Bibcode:2011MNRAS.412.2498M. S2CID 119194025. arXiv:1011.6277 . doi:10.1111/j.1365-2966.2010.18071.x. （原始內容存檔於2016-01-31）.
- ^ Garcia, A. M. General study of group membership. II - Determination of nearby groups. Astronomy and Astrophysics Supplement Series. 1993, 100 (1): 47–90 [2021-07-24]. Bibcode:1993A&AS..100...47G. ISSN 0365-0138. （原始內容存檔於2018-12-24）.
- ^ de Vaucouleurs, G.; de Vaucouleurs, A.; Corwin, J. R. Second reference catalogue of bright galaxies. Second Reference Catalogue of Bright Galaxies. 1976, 1976. Bibcode:1976RC2...C......0D.
外部連結
編輯