中国丽江积分视场光纤光谱仪分辨能力实验室测试结果

The Test Results of Spectral Resolution of China Lijiang Integral Field Unit

中国丽江积分视场光纤光谱仪(China Lijiang Integral Field Unit,简称CHILI)是中国第一台用于夜天文观测的科学级积分视场光纤光谱仪,安装在丽江天文观测站2.4 m光学望远镜上。CHILI运输到中国前,在美国德克萨斯大学奥斯汀分校(University of Texas at Austin)进行了实验室测试。本次实验主要针对CHILI的蓝端,主要测试内容有本底、平场、暗场和波长定标。为了明确知道谱线在像素位置上的精准波长和CHILI探测器的分辨能力,对测试数据进行了波长定标和光谱分辨能力的计算。结果显示,CHILI蓝端的波长范围约为3 500～5 300,在此波长范围内,光谱分辨本领FW H M■5,其对应的光谱分辨率R=λ/?λ约为600～1 000,符合CHILI预期要求。

Integral Field Unit(IFU) can obtain the spatial and spectral information of the observed sources simultaneously, so it is a strong tool to study kinematics, abundances, star formation, structures of galaxies. China Lijiang Integral Field Unit(CHILI) is the first IFU for astronomical night observation in China which was been installed on the 2.4m telescope in Lijiang. The field-of-view of CHILI is 71′′× 65′′and it has 494 fibers. Each fiber corresponds to 3.2′′on sky and the filling factor is greater than or equal to 96%. We tested CHILI in the University of Texas at Austin before it was shipped to China. This test focus on the blue part of CHILI for which we took bias, flat, dark and lamps data. We applied the wavelength calibration and calculate the spectral resolution of CHILI. The results show that the spectral wavelength coverage of CHILI blue part ranges from 3 500 to 5 300 and the spectral resolution R = λ/?λ ranges from 600 to 1 000 in this wavelength range(FW H M■5 ), all satisfying CHILI requirements.