AI 中文总结
该研究针对VLTI向千米级基线扩展的需求，提出带AO预补偿的自由空间传输方案，计划通过专用湍流监测实验表征帕瑞纳千米级水平湍流，为扩展VLTI奠定基础。
AI 中文摘要
VLTI的未来扩展旨在将红外干涉测量推向千米级基线，实现几十微角秒的角分辨率。第一步是将VISTA平台上的新望远镜与现有VLTI基础设施耦合，在帕瑞纳天文台形成1.4千米的基线。在可能的光束传输方案中，受自由空间光通信（FSO）启发的带自适应光学（AO）预补偿的直接自由空间传输，兼具光谱灵活性、成本适中及视场信息保留的优势。本文开展了初步的AO参数优化研究，涵盖拟合误差、光子噪声、非等晕性及闪烁效应，结果表明中等阶次校正（约10×10致动器）可能已足够，但性能关键取决于水平路径上知之甚少的湍流分布。为此，我们提议开展VISTA-VLTI视线路径上的专用湍流监测实验，使用两台配备校准光源的30-50厘米望远镜，该实验结合宽视场夏克-哈特曼传感器（用于湍流体积的层析重建）与事件型（神经形态）相机（可在微秒时间尺度捕捉快速、各向异性湍流）。所得数据集将提供帕瑞纳天文台千米级水平湍流的首次系统表征，为扩展千米基线VLTI铺平道路。
英文摘要
Future extensions of the VLTI aim to push infrared interferometry toward kilometer scale baselines, enabling angular resolutions of a few tens of micro-arcseconds. A first step would couple a new telescope on the VISTA platform to the existing VLTI infrastructure, creating a 1.4 km baseline at Paranal. Among the possible beam-transport solutions, direct free-space transmission with adaptive-optics (AO) pre-compensation, inspired by Free-Space Optical (FSO) communications, offers an attractive combination of spectral flexibility, moderate cost, and preservation of field information. We present a preliminary AO dimensioning study, including fitting error, photon noise, anisoplanatism, and scintillation, showing that moderate-order correction (around 10x10 actuators) may be sufficient, but that performance depends critically on the poorly known turbulence distribution along the horizontal path. We therefore propose a dedicated turbulence-monitoring experiment across the VISTA-VLTI line of sight, using two 30-50 cm telescopes equipped with calibrated light sources. The experiment combines a wide-field Shack-Hartmann sensor for tomographic reconstruction of the turbulence volume with an event-based (neuromorphic) camera capable of capturing fast, anisotropic turbulence at microsecond timescales. The resulting dataset will provide the first systematic characterization of kilometer-scale horizontal turbulence at Paranal, paving the way toward an extended kilometer-baseline VLTI.
