arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1709.00985astro-ph.EP
收藏

根据氢莱曼α的SOHO/SWAN观测的九颗长周期彗星的产水活动:2013-2016

Water Production Activity of Nine Long-Period Comets from SOHO/SWAN Observations of Hydrogen Lyman-alpha: 2013-2016

M. R. Combi, T. T. Mäkinen, J. -L. Bertaux, E. Quémerais, S. Ferron, M. Avery, C. Wright

摘要:

2013年至2016年期间,太阳和日光层观测卫星上的太阳风各向异性莱曼-阿尔法全天空相机观测了最近发现的9颗长周期彗星。它们是C/2012 K1(PanSTARRS),C/2013 US10(Catalina),C/2013 V5(Oukaimeden),C/2013 R1(Lovejoy),C/2014 E2(Jacques),C/2014 Q2(Lovejoy),C/2015 G2(MASTER),C/2014 Q1(PanSTARRS)和C/2013 X1(PanSTARRS)。在这9颗彗星中,6颗是长周期彗星,3颗可能是动力学上的新彗星。使用我们的标准时间分辨模型从885张图像中的每一张计算水的产生速率,该模型考虑了整个水的光解链、放热速度和H原子的碰撞逃逸。对于这些彗星中的大多数,在足够宽的日心距离范围内进行了足够的观测,以计算出幂律拟合,以适应轨道近日点前和近日点后部分的生产率随日心距离的变化。彗星C/2014 Q1(PanSTARRS)的近日点距离仅为~0.3 AU,显示出最不寻常的产水率随日心距离的变化以及由此产生的活动面积变化,这表明当彗星在0.7 AU内时,其活动主要是由冰粒和冰块的持续释放,大大增加了活跃的升华面积超过10倍以上,超过了它在更大的日心距离。一种可能的解释是,彗星的大部分质量在显形期间丢失了。

英文摘要:

Nine recently discovered long-period comets were observed by the Solar Wind Anisotropies (SWAN) Lyman-alpha all-sky camera on board the Solar and Heliosphere Observatory (SOHO) satellite during the period of 2013 to 2016. These were C/2012 K1 (PanSTARRS), C/2013 US10 (Catalina), C/2013 V5 (Oukaimeden), C/2013 R1 (Lovejoy), C/2014 E2 (Jacques), C/2014 Q2 (Lovejoy), C/2015 G2 (MASTER), C/2014 Q1 (PanSTARRS) and C/2013 X1 (PanSTARRS). Of these 9 comets 6 were long-period comets and 3 were possibly dynamically new. Water production rates were calculated from each of the 885 images using our standard time-resolved model that accounts for the whole water photodissociation chain, exothermic velocities and collisional escape of H atoms. For most of these comets there were enough observations over a broad enough range of heliocentric distances to calculate power-law fits to the variation of production rate with heliocentric distances for pre- and post-perihelion portions of the orbits. Comet C/2014 Q1 (PanSTARRS), with a perihelion distance of only ~0.3 AU, showed the most unusual variation of water production rate with heliocentric distance and the resulting active area variation, indicating that when the comet was within 0.7 AU its activity was dominated by the continuous release of icy grains and chunks, greatly increasing the active sublimation area by more than a factor of 10 beyond what it had at larger heliocentric distances. A possible interpretation suggests that a large fraction of the comet's mass was lost during the apparition.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑