Radio Astronomy e-bog

Methods in Computational Physics, Volume 14: Radio Astronomy is devoted to the role of the digital computer both as a control device and as a calculator in addressing problems related to galactic radio noise. This volume contains four chapters and begins with a technical description of the hardware and the special data-handling problems of using radioheliography, with an emphasis on a selection of observational results obtained with the Culgoora radioheliograph and their significance to solar physics and to astrophysics in general. The subsequent chapter examines interstellar dispersion, its influence on time resolution, methods for its measurement, and removing its effect. This chapter also outlines resolution and sampling problems, as well as the computation of the average pulse profile. This chapter surveys also the intensity variations over time scales from microseconds to millions of years and over radio frequency ranges from 40 MHz to 10 GHz. Another chapter highlights the special case of rotational aperture synthesis and its problems, followed by a presentation of data processing necessary to convert the parameters observed with an aperture synthesis telescope into an intensity distribution of part of the sky. The last chapter discusses some data-acquisition and data reduction techniques, as well as some selected problems in data interpretation in spectral-line radio astronomy. This book will be of great importance to geoscientists, physicists, and mathematicians.