Performance Testing Of High Resolution Spectrographs And Design Of Integral Field Unit Systems Based On Small To Medium Aperture Telescopes

Astronomical spectroscopy measurement is an important method to study the stellar physics, such as stellar kinematics, metallicities, rotational velocities and pulsating stars. With increasing of the telescope's aperture and development of detector, astronomical optical spectrographs have got significant breakthroughs in the past few decades. The spectrographs have been designed for three different observation modes:(1) point-like object spectroscopy; (2) multi-object low-resolution spectroscopy; and (3) integral field spectroscopy.High-dispersion spectrographs have huge impacts on a variety of scientific researches on astronomy. First, high resolution spectrum is necessary for studies of metal abundance of stars, exoplanets research and asteroseismology, etc. These projects have different requirements on high-resolution spectrum, but the same thing they pursue is the accurate Doppler measurements. The spectrograph should have high efficiency and high accuracy with its long term stability. Second, the signal to noise ratio of high resolution spectrum is rarely influenced by bright sky-light.With the development of the larger aperture telescopes and adaptive optics (AO) technology, spectrographs can get three-dimensional information (spatial resolution elements×spectral resolution elements) per shot when observing extended celestial objects with high signal to noise ratio. The techniques for 3D imaging spectrographs with integral field units (IFUs) are developed maturely, and they have obvious scientific advantages compared with traditional techniques, such as scanning slit spectrographs. There will be more and more integral field spectrographs combined on large and small telescopes.My thesis mainly concentrate on two aspects:(1) performance testing of Cassegrain fiber-fed echelle high resolution spectrographs operated with the 2.16m telescope (hereafter referred to as 216HRS) at Xinglong observatory and Weihai Echelle Spectrograph (WES) operated with the 1m telescope at Weihai Observatory of Shandong University. My work will give some advice to installation and adjustment of these spectrographs; (2) "lenslet array+fibers" is adopted to design an IFU system on the OMR spectrograph without changing the configuration of OMR spectrograph.In Chapter One, I introduce the importance of astronomical spectroscopic observations. In Chapter Two, I introduce the configuration of 216HRS and describe its test program and performances in detail. In Chapter Three, WES and its good performance are described briefly. I conclude that WES has met the most objectives and specifications. I investigate astronomical spectra calibration with laser frequency comb (LFC) in Chapter Four. LFC is an ideal calibration source for astronomical spectra calibration. However, because of the denseness of the spectrum of LFC, there are some restrictions for LFC in the application of astronomy currently. Fortunately these restrictions will be overcome soon by using a Fabry-Perot filter-cavity. In Chapter Five, I design two different IFUs for the 2.16m telescope and also figure out the spatial resolution and field of view. In the last chapter of this paper, I summarize the recent developments and future trends of astronomical optical spectrographs.