Atoms and rays

This small book is based on lectures that the author has given on various occasions over the past few years to audiences with no more than a secondary education in natural sciences. The lectures covered topics that have long been part of scientific knowledge and have therefore been presented multiple times in an easily understandable form. Nevertheless, they have been included in this presentation, partly for the sake of coherence, but also to clearly illustrate the physical research methods in atomic and radiation physics. However, the main focus was naturally placed on new and the latest research findings, particularly those related to studies on artificial atomic transformation and the investigation of cosmic radiation coming from outer space.