论文标题
区分朦胧的和清晰的热jupiter氛围
Discriminating between hazy and clear hot-Jupiter atmospheres with CARMENES
论文作者
论文摘要
上下文：在紫外线（UV）和蓝光子中观察到的一些热木星的半径通常被解释为是由于高空雾糊状颗粒的瑞利散射所致。但是，雾霾组成及其生产机制尚未完全理解，观察信息仍然受到限制。目的：我们旨在研究HD 209458 B和HD 189733 B中的Hazes存在，并通过分析跨红色光学和近红外波长范围的水蒸气互相关信号的强度，具有高光谱分辨率光谱。方法：在3.5 m calar alto望远镜处使用甲状腺光谱仪观察到两个行星的七个横传。他们的多普勒偏移信号使用了脱尿和恒星的贡献，使用了损坏算法SYSREM。随后，残留光谱与水蒸气模板以0.70-0.96 $μ$ m的速度交叉相关，以测量水蒸气吸收带的强度。结果：在HD 209458 b中以$5.2σ$在一个过境中检测到光学水蒸气带，而在HD 189733的四个过渡中未发现它们的证据。因此，在HD 209458 B中发现，与近红外相比的光学带的相对强度比在HD 189733 b中更大。结论：与HD 209458 B中的检测相比，我们解释了HD 189733 B透射光谱中光条带的未检测，这是由于前一个行星中存在高海拔危险的，后者在后者中很大程度上不存在。这与哈勃太空望远镜先前的测量结果一致。我们表明，当前可用的热木星观测值可用于研究其大气中的雾化灭绝。
Context: Relatively large radii of some hot Jupiters observed in the ultraviolet (UV) and blue-optical are generally interpreted to be due to Rayleigh scattering by high-altitude haze particles. However, the haze composition and its production mechanisms are not fully understood, and observational information is still limited. Aims: We aim to study the presence of hazes in the atmospheres of HD 209458 b and HD 189733 b with high spectral resolution spectra by analysing the strength of water vapour cross-correlation signals across the red optical and near-infrared wavelength ranges. Methods: A total of seven transits of the two planets were observed with the CARMENES spectrograph at the 3.5 m Calar Alto telescope. Their Doppler-shifted signals were disentangled from the telluric and stellar contributions using the detrending algorithm SYSREM. The residual spectra were subsequently cross-correlated with water vapour templates at 0.70-0.96 $μ$m to measure the strength of the water vapour absorption bands. Results: The optical water vapour bands were detected at $5.2 σ$ in HD 209458 b in one transit, whereas no evidence of them was found in four transits of HD 189733 b. Therefore, the relative strength of the optical water bands compared to those in the near-infrared were found to be larger in HD 209458 b than in HD 189733 b. Conclusions: We interpret the non-detection of optical water bands in the transmission spectra of HD 189733 b, compared to the detection in HD 209458 b, to be due to the presence of high-altitude hazes in the former planet, which are largely absent in the latter. This is consistent with previous measurements with the Hubble Space Telescope. We show that currently available CARMENES observations of hot Jupiters can be used to investigate the presence of haze extinction in their atmospheres.
