This collection of articles contains a systematic outline of original experimental and theoretical research on photoproduction of neutral pions at protons and at a strongly bound system of a few nucleons, i.e., the helium nucleus. Spark chambers and their use as spectrometers for photons and electrons are described in detail. The articles of the collection include information on a novel method of determining the efficiency of recording apparatus by generating monochromatic photons. The articles de- scribe original theoretical research on the optical anisotropy of nuclei. Problems encountered...

In this volume are collected scientific research reports written in recent years at the Radio-Astronomy Laboratory in the field of radio-astronomical apparatus and methods of ob- servation. Modern radiometers of high sensitivity, using masers and parametric amplifiers, have been installed at the R T-22 radio telescope of the Laboratory's Radio-Astronomy station. Some of the papers are devoted to a description of these original radiometers and to their operating conditions. Considerable space is given to a description of the meter-wave equipment and to the ad- justment of the DKR-1000 diapason...