System analysis and expected performance of a high-contrast module for HARMONI
System analysis and expected performance of a high-contrast module for HARMONI
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HARMONI 高对比度模块的系统分析和预期性能
DOI：
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发表时间：
2018
期刊：
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通讯作者：
C. Vérinaud
中科院分区：
文献类型：
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作者：
A. Carlotti;F. Hénault;K. Dohlen;J. Sauvage;P. Rabou;Y. Magnard;A. Vigan;D. Mouillet;G. Chauvin;P. Vola;M. Bonnefoy;T. Fusco;K. El Hadi;N. Thatte;F. Clarke;M. Tecza;I. Bryson;H. Schnetler;C. Vérinaud
HARMONI是ESO的极大望远镜（ELT）的第一光可见光和近红外积分场摄谱仪，该望远镜将位于智利Cerro Armazones的顶部。单共轭自适应光学（SCAO）子系统将在奈奎斯特采样的0.61 x 0.86弧秒视场中提供衍射限制光谱图像，光谱分辨率为R=3000-20000。在仪器内部，一个高对比度模块（HCM）可以使HARMONI能够光谱表征年轻的巨型系外行星（和盘），其通量比低至10−6，距离它们的星星100- 200质量。假设HARMONI的中继光学器件的表面质量满足特定要求，这将通过变迹光瞳日冕仪来实现，以衰减星星的衍射光并限制探测器上的动态范围，以及内部ZELDA波前传感器来校准非公共路径像差。该通信介绍了（a）为满足这些要求而进行的系统分析，以及拟议的HCM设计，（B）一个端到端仿真工具，该工具已被构建用于产生长达一小时的观测的真实数据立方体，以及（c）HCM的估计性能，该性能是通过对仿真数据应用差分成像技术得出的。
HARMONI is a first-light visible and near-IR integral field spectrograph of ESO’s Extremely Large Telescope (ELT) which will sit on top of Cerro Armazones, Chile. A Single Conjugate Adaptive Optics (SCAO) subsystem will provide diffraction-limited spectro-images in a Nyquist-sampled 0.61 x 0.86 arcsec field of view, with a R=3000-20000 spectral resolution. Inside the instrument, a High Contrast Module (HCM) could give HARMONI the ability to spectrally characterize young giant exoplanets (and disks) with flux ratio down to 10−6 as close as 100-200mas from their star. This would be achieved with an apodized pupil coronagraph to attenuate the diffracted light of the star and limit the dynamic range on the detector, and an internal ZELDA wavefront sensor to calibrate non-common path aberrations, assuming that the surface quality of the relay optics of HARMONI satisfy specific requirements. This communication presents (a) the system analysis that was conducted to converge towards these requirement, and the proposed HCM design, (b) an end-to-end simulation tool that has been built to produce realistic datacubes of hour-long observations, and (c) the estimated performance of the HCM, which has been derived by applying differential imaging techniques on the simulated data.