Observations of comet C/2020 F3 (NEOWISE) with IRAM telescopes
Observations of comet C/2020 F3 (NEOWISE) with IRAM telescopes
复制标题
使用 IRAM 望远镜观测彗星 C/2020 F3 (NEOWISE)
DOI：
10.1051/0004-6361/202244970
复制
发表时间：
2022
影响因子：
6.5
通讯作者：
Moreno, R.
中科院分区：
文献类型：
--
作者：
Biver, N.;Boissier, J.;Bockelée-Morvan, D.;Crovisier, J.;Cottin, H.;Cordiner, M. A.;Roth, N. X.;Moreno, R.
我们介绍了彗星C/2020 F3（NEOWISE）的毫米波光谱和连续观测结果，这些观测是在2020年7月22日，25日至27日和8月7日使用射电天文学研究所（IRAM）30米和NOEMA扩展毫米阵列（NOEMA）望远镜进行的。HCN，HNC，CH3OH CS，H2CO，CH3CN，H2S和CO的生产率与其他六种物质的上限。这颗彗星的丰度在其他彗星的观测范围内。CO丰度较低（相对于水为3.2%），而H2S相对丰富（相对于水为1.1%）。H2CO丰度随日心距离的变化很大，可能与尘埃或大分子源的分布有关。的CH3OH和H2S的生产率显示出较低的下降后近日点比水。根据连续体的干涉测量图（意味着r <4.7公里），没有检测到核点源的贡献，但这产生了对尘埃产生率的估计，导致2020年7月22日的相对较低的尘气比为0.7 ± 0.3。
We present the results of millimetre-wave spectroscopic and continuum observations of the comet C/2020 F3 (NEOWISE) undertaken with the Institut de RadioAstronomie Millimétrique (IRAM) 30-m and the NOrthern Extended Millimeter Array (NOEMA) telescopes on 22, 25–27 July, and 7 August 2020. Production rates of HCN, HNC, CH3OH CS, H2CO, CH3CN, H2S, and CO were determined with upper limits on six other species. The comet shows abundances within the range observed for other comets. The CO abundance is low (3.2% relative to water), while H2S is relatively abundant (1.1% relative to water). The H2CO abundance shows a steep variation with heliocentric distance, possibly related to a distributed production from the dust or macro-molecular source. The CH3OH and H2S production rates show a slower decrease post-perihelion than water. There was no detection of the nucleus point source contribution based on the interferometric map of the continuum (implying a size ofr <4.7 km), but this yielded an estimate of the dust production rate, leading to a relatively low dust-to-gas ratio of 0.7 ± 0.3 on 22.4 July 2020.