KMT-2021-BLG-0240: Microlensing event with a deformed planetary signal
KMT-2021-BLG-0240: Microlensing event with a deformed planetary signal
复制标题
KMT-2021-BLG-0240：具有变形行星信号的微透镜事件
DOI：
10.1051/0004-6361/202243161
复制
发表时间：
2022
影响因子：
6.5
通讯作者：
Ryu, Yoon-Hyun
中科院分区：
文献类型：
--
作者：
Han, Cheongho;Kim, Doeon;Yang, Hongjing;Gould, Andrew;Jung, Youn Kil;Albrow, Michael D.;Chung, Sun-Ju;Hwang, Kyu-Ha;Lee, Chung-Uk;Ryu, Yoon-Hyun
微透镜事件KMT-2021-BLG-0240的光变曲线在单透镜单源模型的0.1等水平处的峰值附近表现出具有复杂特征的短暂异常。我们进行建模的透镜光变曲线根据各种解释，以揭示性质的anomality.MethodsIt发现，异常不能解释与通常的模型的基础上的二元透镜（2L 1 S）或二元源（1 L2 S）的解释。然而，一个有行星伴星的2L 1 S模型可以描述部分异常，这表明异常可能是由第三透镜组件或近伴星变形的。从额外的建模，我们发现，所有的异常的功能可以解释与三透镜（3L 1 S）模型或二元透镜二元源（2L 2S）模型。然而，这是很难验证的2L 2S模型，因为光变曲线没有表现出的签名所引起的源轨道运动和椭球体的变化预期的源恒星之间的密切分离，根据该模型。因此，我们的结论是，这两种解释不能区分与现有的数据，可以是correct.ResultsAccording到3L 1 S的解决方案，该透镜是一个行星系统与两个亚木星质量的行星，其中行星的质量为0.32- 0.47 MJ和0.44- 0.93 MJ，他们的轨道M矮星主机。另一方面，根据2L 2S解，透镜是一个质量约为0.21 M的单行星系统，它的恒星是一颗晚K矮星，其源是一颗由次巨星或转折星星的主星和一颗晚G矮星的副星组成的双星。到行星系统的距离因解的不同而不同：根据3L 1 S解，约为7.0 kpc;根据2L 2S解，约为6.6 kpc。
AimsThe light curve of the microlensing event KMT-2021-BLG-0240 exhibits a short-lasting anomaly with complex features near the peak at the 0.1 mag level from a single-lens single-source model. We conducted modeling of the lensing light curve under various interpretations to reveal the nature of the anomaly.MethodsIt is found that the anomaly cannot be explained with the usual model based on a binary-lens (2L1S) or a binary-source (1L2S) interpretation. However, a 2L1S model with a planet companion can describe part of the anomaly, suggesting that the anomaly may be deformed by a tertiary lens component or a close companion to the source. From the additional modeling, we find that all the features of the anomaly can be explained with either a triple-lens (3L1S) model or a binary-lens binary-source (2L2S) model. However, it is difficult to validate the 2L2S model because the light curve does not exhibit signatures induced by the source orbital motion and the ellipsoidal variations expected by the close separation between the source stars according to the model. We, therefore, conclude that the two interpretations cannot be distinguished with the available data, and either can be correct.ResultsAccording to the 3L1S solution, the lens is a planetary system with two sub-Jovian-mass planets in which the planets have masses of 0.32–0.47MJand 0.44–0.93MJ, and they orbit an M dwarf host. According to the 2L2S solution, on the other hand, the lens is a single planet system with a mass of ~0.21MJorbiting a late K-dwarf host, and the source is a binary composed of a primary of a subgiant or a turnoff star and a secondary of a late G dwarf. The distance to the planetary system varies depending on the solution: ~7.0 kpc according to the 3L1S solution and ~6.6 kpc according to the 2L2S solution.