标题： 三十米望远镜红外成像光谱仪（IRIS）：灵敏度与模拟 显示英文标题

标题： The infrared imaging spectrograph (IRIS) for TMT: sensitivities and simulations

摘要： 我们给出了未来三十米望远镜（TMT）当前设计的红外成像光谱仪（IRIS）对点源和分辨天体源的灵敏度估算。与目前8-10米地基望远镜上的系统相比，IRIS借助TMT的自适应光学系统，在近红外波段（0.84 - 2.45 {\mu }m）将实现前所未有的点源灵敏度。IRIS成像仪在总共5小时的积分时间内，能够在近红外宽带滤光片（Z, Y, J, H, K）上对26至29星等（AB）的点源执行几个百分比的测光。具有多种尺度和滤光片的积分场光谱仪将在5小时总积分时间内以R=4,000的光谱分辨率对22至26星等（AB）的点源获得良好的信噪比。我们还展示了模拟的3D IRIS数据，涉及分辨的高红移恒星形成星系（1 < z < 5），这表明了该仪器在探测早期宇宙中星系动力学、组装过程以及化学丰度方面的非凡潜力。凭借其最精细的空间尺度，IRIS能够研究明亮、大质量、高红移的恒星形成星系（恒星形成率 ~ 10 - 100 M yr-1）的分辨率约为100 pc。利用最粗的空间尺度，IRIS能够观测到更暗淡、质量较低的高红移星系，其综合恒星形成率小于1 M yr-1，与当前的积分场光谱仪相比，灵敏度提高了3到10倍。通过结合TMT的衍射极限与精细和粗略的空间尺度组合，我们将显著提高对早期星系形成过程及其随后演变为现代星系的理解。 显示英文摘要

摘要： We present sensitivity estimates for point and resolved astronomical sources for the current design of the InfraRed Imaging Spectrograph (IRIS) on the future Thirty Meter Telescope (TMT). IRIS, with TMT's adaptive optics system, will achieve unprecedented point source sensitivities in the near-infrared (0.84 - 2.45 {\mu}m) when compared to systems on current 8-10m ground based telescopes. The IRIS imager, in 5 hours of total integration, will be able to perform a few percent photometry on 26 - 29 magnitude (AB) point sources in the near-infrared broadband filters (Z, Y, J, H, K). The integral field spectrograph, with a range of scales and filters, will achieve good signal-to-noise on 22 - 26 magnitude (AB) point sources with a spectral resolution of R=4,000 in 5 hours of total integration time. We also present simulated 3D IRIS data of resolved high-redshift star forming galaxies (1 < z < 5), illustrating the extraordinary potential of this instrument to probe the dynamics, assembly, and chemical abundances of galaxies in the early universe. With its finest spatial scales, IRIS will be able to study luminous, massive, high-redshift star forming galaxies (star formation rates ~ 10 - 100 M yr-1) at ~100 pc resolution. Utilizing the coarsest spatial scales, IRIS will be able to observe fainter, less massive high-redshift galaxies, with integrated star formation rates less than 1 M yr-1, yielding a factor of 3 to 10 gain in sensitivity compared to current integral field spectrographs. The combination of both fine and coarse spatial scales with the diffraction-limit of the TMT will significantly advance our understanding of early galaxy formation processes and their subsequent evolution into presentday galaxies.