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arXiv 1202.3435astro-ph.EP
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WASP-3b的KS波段热辐射探测

Detection of Ks-band Thermal Emission from WASP-3b

Ming Zhao, Jennifer Milburn, Travis Barman, Sasha Hinkley, Mark R. Swain, Jason Wright, John D. Monnier

摘要:

我们报告的热发射探测热木星WASP-3b在KS波段,使用新开发的指导计划的WIRC仪器在Palomar黑尔200 in望远镜。我们的新的引导方案提高了望远镜的引导精度的5-7倍,显着减少了相关的系统在测量光变曲线。这导致了探测到深度为0.181% \pm 0.020%(9-σ)的二次日食--这是WIRC测光精度的重大改进,也证明了Palomar/WIRC对系外行星大气进行高质量测量的能力。我们测得的日食深度不能用具有热再分布的模型大气来解释,而是倾向于一个纯辐射平衡的情况,在行星表面没有再分布。我们的测量也给出了0.5045 \pm 0.0020的食相位中心,对应于0.0070 \pm 0.0032的ecosω。这个结果与圆形轨道一致,尽管它也表明行星的轨道可能稍微偏心。可能的非零离心率提供了对恒星-行星系统潮汐循环过程的深入了解,但也可能是由系统中的第二颗低质量行星引起的,正如先前的凌日时间变化研究所建议的那样。更多的二次日食观测,特别是在多个波长,是必要的,以确定行星大气的温度-压力分布,并揭示其轨道偏心率。

英文摘要:

We report the detection of thermal emission from the hot Jupiter WASP-3b in the KS band, using a newly developed guiding scheme for the WIRC instrument at the Palomar Hale 200in telescope. Our new guiding scheme has improved the telescope guiding precision by a factor of ~5-7, significantly reducing the correlated systematics in the measured light curves. This results in the detection of a secondary eclipse with depth of 0.181%\pm0.020% (9-σ) - a significant improvement in WIRC's photometric precision and a demonstration of the capability of Palomar/WIRC to produce high quality measurements of exoplanetary atmospheres. Our measured eclipse depth cannot be explained by model atmospheres with heat redistribution but favor a pure radiative equilibrium case with no redistribution across the surface of the planet. Our measurement also gives an eclipse phase center of 0.5045\pm0.0020, corresponding to an ecosω of 0.0070\pm0.0032. This result is consistent with a circular orbit, although it also suggests the planet's orbit might be slightly eccentric. The possible non-zero eccentricity provides insight into the tidal circularization process of the star-planet system, but also might have been caused by a second low-mass planet in the system, as suggested by a previous transit timing variation study. More secondary eclipse observations, especially at multiple wavelengths, are necessary to determine the temperature-pressure profile of the planetary atmosphere and shed light on its orbital eccentricity.

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。

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