AI 中文总结
研究团队在南非大望远镜上演示了一款新型简单的天文光梳，为其高分辨率光谱仪提供全红通道校准，获得波长解与线扩散函数，该架构可扩展至蓝波段，有望推广天文光梳技术。
AI 中文摘要
天文光梳是包含数千条狭窄、均匀间隔且原子参考谱线的宽带激光器，为地基光学望远镜提供了黄金标准的波长校准，具备达到厘米/秒精度的潜力，可用于开普勒、TESS和PLATO等空间测光任务系外行星候选体的径向速度后续观测。当前的天文光梳，尤其是工作在可见光波段的，结构复杂且成本高昂，令许多天文台难以企及。本文展示了一种新型简单天文光梳概念的首次在轨仪器演示，可为南非大望远镜的高分辨率光谱仪（SALT-HRS）的整个550 nm至890 nm红通道提供校准光。通过GPS参考的二极管泵浦钛蓝宝石激光器在氮化硅波导中产生的倍频程超连续谱被滤波至21 GHz，再经光纤传输至光谱仪。利用该天文光梳，我们获得了SALT-HRS一个级次的波长解以及该仪器与波长相关的线扩散函数。该独特的简单架构具备向蓝色光谱区域进一步扩展的潜力，使可见光至红外波段的天文光梳技术能够为更广泛的天文台所应用。
英文摘要
Astrocombs -- broadband lasers comprising thousands of narrow, uniformly spaced and atomically-referenced spectral lines -- offer gold-standard wavelength calibration for ground-based optical telescopes, with the potential for the cm/s precision needed for radial-velocity follow-ups of exoplanet candidates from photometric space missions like Kepler, TESS and PLATO. Current astrocombs, particularly those operating in the visible spectrum, are complex and expensive, putting them beyond the reach of many observatories. Here, we present the first on-instrument demonstration of a new and simple astrocomb concept, providing calibration light across nearly the entire 550 nm to 890 nm red channel of the Southern African Large Telescope's High Resolution Spectrograph (SALT-HRS). An octave-spanning supercontinuum generated in a silicon nitride waveguide by a GPS-referenced diode-pumped Ti:sapphire laser is filtered to 21 GHz before fibre delivery to the spectrograph. Using the astrocomb, we obtain the wavelength solution for one order of SALT-HRS and the wavelength-dependent line-spread function of the instrument. With potential for further extension into the blue spectral region, this uniquely simple architecture brings visible-to-infrared astrocomb technology within the reach of a wider range of astronomical observatories.
