NGC 346是位於杜鵑座的一個年輕 疏散星團，是與小麥哲倫星系（SMC）的星雲相關的恆星集團[4]。它是由蘇格蘭天文學家詹姆士·敦洛普於1826年8月1日發現的。約翰·路易·埃米爾·德雷耳描述其為「明亮、大、非常不規則的圖形，中間明亮得多，類似於雙星，有斑點但未能分辨」[5]。星團週邊是小麥哲倫星系中最亮的恆星之一：多星系統HD 5980[6]。
該星團位於小麥哲倫星系中最亮，命名為N66的電離氫區中心附近[7]。它位於這個星系棒的東北部分[8]，恆星調查已經在這個星團的方向上發現了230顆大質量的OB星[4]。33個星團成員是O型星，其中有11顆是O6.5型或更早[8]。星團的內部7017462851637220078♠15 pc半徑看起來集中凝聚，而該體積外部的區域則較為分散[9]。中心附近最年輕的星團成員年齡不到200萬歲[7]，觀測結果表明，該星團仍在進行高效率的恆星形成[7]。星團的形成速率估計為6997400000000000000♠(4±1)×10−3 太陽質量/年[9]。
圖集
顯著的恆星[10]
| Walborn
|
ELS
|
MPG
|
NMC
|
SSN
|
光譜
類型
|
有效
溫度 (K)
|
絕對
星等
|
熱星等
|
質量
(M☉)
|
|
|
207758
|
755
(HD 5980/AB5)
|
|
|
LBV
WN4
OI
|
45,000
45,000
34,000
|
−7.1
(−8.1) −6.8
−6.7
|
−11.135
−10.885
−9.885
|
61
66
34
|
| 1
|
|
435
|
26
|
7
|
O5.5If
|
43,400
|
−6.7
|
−10.7
|
91
|
|
|
1
|
789
|
|
5
|
O7If
|
38,900
|
−7
|
−10.7
|
85
|
| 3
|
|
355
|
29
|
9
|
O3V
|
51,300
|
−5.7
|
−10.3
|
76
|
| 6
|
7
|
324
|
32
|
13
|
O4V
|
48,600
|
−5.2
|
−9.6
|
54
|
| 4
|
|
342
|
30
|
11
|
O5.5V
|
44,900
|
−5.5
|
−9.7
|
53
|
|
|
|
368
|
28
|
15
|
O5.5V
|
44,900
|
−5
|
−9.2
|
43
|
| 2
|
|
470
|
25
|
|
O8.5III
|
35,700
|
−5.4
|
−8.9
|
34
|
參考資料
- ^ Hubble Heritage Site. Results for NGC 346. [2007-04-03]. （原始内容存档于2009-02-11）.
- ^ 2.0 2.1 Sturm, R.; et al. The XMM-Newton survey of the Small Magellanic Cloud: The X-ray point-source catalogue. Astronomy & Astrophysics. October 2013, 558: 31. Bibcode:2013A&A...558A...3S. S2CID 118620464. arXiv:1307.7594
. doi:10.1051/0004-6361/201219935. A3.
- ^ NGC 346. SIMBAD. 斯特拉斯堡天文資料中心.
- ^ 4.0 4.1 Dufton, P. L.; et al. The NGC 346 massive star census. Nitrogen abundances for apparently single, narrow lined, hydrogen core burning B-type stars. Astronomy & Astrophysics. February 2020, 634: 15. Bibcode:2020A&A...634A...6D. S2CID 209376523. arXiv:1912.07539 . doi:10.1051/0004-6361/201936921. A6.
- ^ Seligman, Courtney. New General Catalogue objects: NGC 300 - 349. cseligman.com. [2020-09-17]. （原始内容存档于2023-07-29）.
- ^ Nazé, Y.; et al. An X-Ray Investigation of the NGC 346 Field in the Small Magellanic Cloud I. The Luminous Blue Variable HD 5980 and the NGC 346 Cluster. The Astrophysical Journal. November 2002, 580 (1): 225–234. Bibcode:2002ApJ...580..225N. S2CID 118907796. arXiv:astro-ph/0208289 . doi:10.1086/343079.
- ^ 7.0 7.1 7.2 Dufton, P. L.; et al. A census of massive stars in NGC 346. Stellar parameters and rotational velocities. Astronomy & Astrophysics. June 2019, 626: 28. Bibcode:2019A&A...626A..50D. S2CID 148571638. arXiv:1905.03359 . doi:10.1051/0004-6361/201935415. A50.
- ^ 8.0 8.1 Rubio, M.; et al. Massive young stellar objects in the N 66/NGC 346 region of the SMC. Astronomy & Astrophysics. July 2018, 615: 9. Bibcode:2018A&A...615A.121R. S2CID 119190580. arXiv:1803.10833 . doi:10.1051/0004-6361/201730487. A121.
- ^ 9.0 9.1 Hony, S.; et al. Star formation rates from young-star counts and the structure of the ISM across the NGC 346/N66 complex in the SMC. Monthly Notices of the Royal Astronomical Society. April 2015, 448 (2): 1847–1862. Bibcode:2015MNRAS.448.1847H. arXiv:1501.03634 . doi:10.1093/mnras/stv107.
- ^ Massey, Philip; Waterhouse, Elizabeth; DeGioia-Eastwood, Kathleen. The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. I. Results from 19 OB Associations in the Magellanic Clouds. The Astronomical Journal. May 2000, 119 (5): 2214–2241. Bibcode:2000AJ....119.2214M. ISSN 0004-6256. S2CID 16891188. arXiv:astro-ph/0002233 . doi:10.1086/301345.
外部連結
