2I/Borisov: A C2-depleted interstellar comet
2I/Borisov: A C2-depleted interstellar comet
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2I/鲍里索夫：一颗贫碳星际彗星
DOI：
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发表时间：
2019
影响因子：
6.5
通讯作者：
J. Kleyna
中科院分区：
文献类型：
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作者：
C. Opitom;A. Fitzsimmons;E. Jehin;Y. Moulane;O. Hainaut;K. Meech;Bin Yang;C. Snodgrass;M. Micheli;J. Keane;Z. Benkhaldoun;J. Kleyna
目标。第一个活跃的星际物体2 I/Borisov的发现为研究另一个行星系统中的行星形成过程提供了前所未有的机会。特别是，2 I的光谱观测使我们能够限制其核冰的组成。
方法.我们在2019年9月30日至10月13日期间使用4.2米William Herschel和2.5米Isaac Newton望远镜获得了2 I的光谱，当时彗星距离太阳在2.5 Au和2.4 Au之间。我们还在9月11日至10月17日的15个晚上用宽带滤光片拍摄了彗星，并在10月18日和20日用CN窄带滤光片拍摄了彗星。
结果宽频带影像证实尘埃彗发的颜色（B − V = 0.82 ± 0.02，V − R = 0.46 ± 0.03，R − I = 0.44 ± 0.03，B − R = 1.28 ± 0.03）与太阳系彗星相同。 我们在所有光谱和TRAPPIST窄带图像中检测到CN发射，产生速率在1.6 × 1024和2.1 × 1024 molec/s之间。 未检测到其他物种。10月2日，我们确定了C2、C3和OH生成速率的三西格玛上限分别为6 × 1023 molec/s、2 × 1023 molec/s和2 ×1027 molec/s。 在我们的观察期间，CN产生速率或A（0）fρ没有显著增加。最后，我们将Q（C2）/Q（CN）比值设为0.3（10月13日）。由此，我们得出结论，2 I是高度缺乏C2，可能有一个类似的太阳系碳链耗尽彗星的组成。
Aims. The discovery of the first active interstellar object 2I/Borisov provides an unprecedented opportunity to study planetary formation processes in another planetary system. In particular, spectroscopic observations of 2I allow us to constrain the composition of its nuclear ices.
Methods. We obtained optical spectra of 2I with the 4.2 m William Herschel and 2.5 m Isaac Newton telescopes between 2019 September 30 and October 13, when the comet was between 2.5 au and 2.4 au from the Sun. We also imaged the comet with broadband filters on 15 nights from September 11 to October 17, as well as with a CN narrow-band filter on October 18 and 20, with the TRAPPIST-North telescope.
Results. Broadband imaging confirms that the dust coma colours (B − V = 0.82 ± 0.02, V − R = 0.46 ± 0.03, R − I = 0.44 ± 0.03, B − R = 1.28 ± 0.03) are the same as for Solar System comets. We detect CN emission in all spectra and in the TRAPPIST narrow-band images with production rates between 1.6 × 1024 and 2.1 × 1024 molec/s. No other species are detected. We determine three-sigma upper limits for C2, C3, and OH production rates of 6 × 1023 molec/s, 2 × 1023 molec/s and 2 × 1027 molec/s, respectively, on October 02. There is no significant increase of the CN production rate or A(0)fρ during our observing period. Finally, we place a three-sigma upper limit on the Q(C2)/Q(CN) ratio of 0.3 (on October 13). From this, we conclude that 2I is highly depleted in C2, and may have a composition similar to Solar System carbon-chain depleted comets.
2I/Borisov 的碳链耗尽
DOI：
10.3847/2041-8213/ab6a08
发表时间：
2020
期刊：
The Astrophysical Journal
影响因子：
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作者：
Kareta, Theodore;Andrews, Jennifer;Noonan, John W.;Harris, Walter M.;Smith, Nathan;O’Brien, Patrick;Sharkey, Benjamin N.;Reddy, Vishnu;Springmann, Alessondra;Lejoly, Cassandra
通讯作者：
Lejoly, Cassandra