MgII Absorbers at High Redshift Using J-Band High Resolution Spectroscopy on the Hobby-Eberly Telescope

摘要AST 0123885丘吉尔这是一个探索研究(SGER)项目，用于修改和测试红外相机和光谱仪(JCAM)，它将用于在德克萨斯大学麦克唐纳天文台的霍比-埃伯利望远镜(HET)上获取光谱。然后，这些数据将被用来测试改进后的设备在0.95至1.35毫米波长范围内测量极弱类星体光谱的适宜性，这相当于在2796-2803埃吸收线中z=2.4至3.8的红移。获取这些数据对类星体研究的潜在科学影响非常高。这一潜在的非常重要的数据可能无法通过HET获得的风险。从目前望远镜在视觉上的性能推断，很明显，拟议的改进后的光谱仪有望用于获得V=17毫克以上亮度的源的数据。然而，在这个红移范围内的类星体位于星等范围V=18到19 MAG之间。模拟表明，对于成像盘为1.5角秒的18MAG天体，类星体中的吸收线在夜空背景下是可以探测到的，但HET目前没有保持1.3至1.5角秒图像大小所需的长期目标上稳定性。尽管望远镜升级可能会提供必要的图像质量，但确定该仪器极限能力的唯一有意义的方法是进行实际测试。该项目的资金由NSF河外天文与宇宙学计划(AST/EXC)提供。*

ABSTRACT AST 0123885Churchill This is a Small Grant for Exploratory Research (SGER) project to modify and test an infrared camera and spectrograph (the JCAM) which will be used to obtain spectra on the Hobby-Eberly Telescope (HET) at the McDonald Observatory of the University of Texas. This data will then be used to test the suitability of the modified equipment for measuring spectra of very faint Quasars in the wavelength range of 0.95 to 1.35 millimicrons which corresponds to redshifts of z= 2.4 to 3.8 In the MgII, 2796 - 2803 Angstrom absorption line. The potential scientific impact of obtaining this data for Quasar research is very high. There is a risk that this potentially very important data may not be obtainable with the HET. Extrapolating from the present performance of the telescope in the visual, it is clear that the proposed, modified spectrograph is expected to be useful for obtaining data on sources brighter than V=17 mag. However, the quasars at this redshift range lie in the magnitude range V=18 to 19 mag. Simulations show that the absorption lines in the quasars are detectable against the night sky background for 18th mag objects with an image disk of 1.5 arc seconds but the HET does not at present have the long-term, on-target stability necessary to maintain image sizes of 1.3 to 1.5 arc seconds. Although a telescope upgrade may provide the necessary image quality, the only meaningful way to determine the limiting capabilities of this instrument is to conduct actual tests. Funding for this project was provided by the NSF program for Extragalactic Astronomy & Cosmology (AST/EXC).***