Radio & Optical Interferometry: Basic Observing Techniques and Data Analysis

摘要: Astronomers usually need the highest angular resolution possible, but blurring effect of diffraction imposes a fundamental limit on image quality from any single telescope. Interferometry allows light collected at widely-separated telescopes to be combined in order synthesize an aperture much larger than individual telescope thereby improving by orders magnitude. Radio and millimeter wave astronomers depend interferometry achieve par with conventional visible infrared telescopes. Interferometers wavelengths extend below milli-arcsecond level open up unique research areas imaging stellar surfaces circumstellar environments. In this chapter basic principles are reviewed emphasis common features for radio optical observing. While many techniques interferometers all wavelengths, crucial differences identified that will help new practitioners avoid unnecessary confusion pitfalls. Concepts essential writing observing proposals planning observations described, depending science wavelength, resolution, field view required. Atmospheric ionospheric turbulence degrades longest-baseline significantly reducing stability interference fringes. Such instabilities represent persistent challenge, phase-referencing phase closure have been developed deal them. Synthesis large datasets has become routine straightforward process observatories, remains challenging facilities. In context commonly-used reconstruction algorithms CLEAN MEM presented. Lastly, concise overview current facilities is included as appendix.