HRT activity monitoring of solar-like stars: The Ca II Infrared triplet

相对较少研究的恒星活动指标是位于近红外的caii三重态，而caii HK线已经被用作恒星色球活动指标几十年了。由于仪器问题，这些谱线的同时数据集很少，然而，随着梯队光谱仪的可用性，覆盖了很宽的光谱范围，可以直接获得Ca II H&K和IRT谱线的同时覆盖。需要这些同时采集的数据集来回答基于Ca II IRT的活度指标是否能与基于Ca II H&K线的活度指标发挥同样的作用。这些谱线是由相同的离子产生的，然而，它们是在不同的大气层产生的，因此不需要具有相同的诊断能力。无论是在CARMENES上，对M恒星周围行星的光谱调查，还是在GAIA上，只有Ca II IRT将被覆盖作为活动诊断，并且由于这些原因，已经有必要对冷恒星进行活动研究，同时覆盖Ca II线，以便能够将即将到来的Ca II IRT数据与Ca II H&K线上的大量文献联系起来。在提出的项目背景下，我们希望在更大的恒星样本中同时观测和监测Ca II H&K和Ca II IRT线。通过机器人望远镜可以经济地获得所需的光谱时间序列。汉堡机器人望远镜可以生成所需的数据，并可用于拟议的项目。

A relatively little study stellar activity indicator is the Ca II triplet, Iocated in the near infrared, while the Ca II HK lines haven been used for decades as stellar chromospheric activity indicators. Because of instrumental problems few simultaneous data sets of these lines are available, however, with the availability of echelle spectrographs, covering a wide spectral range, it is straightforward to obtain simultaneous coverage of the Ca II H&K and IRT lines. Such simultaneously taken data sets are required to answer the question if Ca II IRT based activity indicators can play the same role as those based on the Ca II H&K lines. These lines are produced by the same ion, however, they are generated in different atmospheric layers and need thus not have the same diagnostic power. Both on CARMENES, a spectroscopic survey for planets around M stars, as well as on GAIA, only the Ca II IRT will be covered as an activity diagnostics, and already for these reasons it is necessary to carry out an activity study of cool stars, which covers both Ca II lines simultaneously, to be able to relate the upcoming Ca II IRT data to the huge body of literature available on the Ca II H&K lines. In the context of the proposed project we want to simultaneously observe and monitor the Ca II H&K and Ca II IRT lines in a larger sample of stars. The required spectral time series can be obtained economically through robotic telescopes. The Hamburg Robotic Telescope can generate the required data and is available to the proposed project.