Non-thermal radio astronomy

© 2013 Elsevier B.V. All rights reserved. This presentation starts with Karl Jansky's discovery of cosmic radio emission in 1933 and notes the striking similarities to Hess's discovery of cosmic-rays in 1912. At first it was assumed that this radio emission was thermal but in 1939 Grote Re...

Full description

Bibliographic Details
Main Author: Ekers, Ronald
Format: Journal Article
Published: 2014
Online Access:http://hdl.handle.net/20.500.11937/47079
_version_ 1848757735866236928
author Ekers, Ronald
author_facet Ekers, Ronald
author_sort Ekers, Ronald
building Curtin Institutional Repository
collection Online Access
description © 2013 Elsevier B.V. All rights reserved. This presentation starts with Karl Jansky's discovery of cosmic radio emission in 1933 and notes the striking similarities to Hess's discovery of cosmic-rays in 1912. At first it was assumed that this radio emission was thermal but in 1939 Grote Reber discovered that it was stronger at longer wavelengths, requiring a non-thermal emission process. These discoveries had a revolutionary impact on astronomy and radio astronomy was born. The interpretation of this non-thermal radiation as synchrotron emission from high energy particles in the interstellar medium did not occur until the late 1940s but then it provided the link between radio astronomy and cosmic-ray research. Ginzburg, in particular, saw that cosmic-ray astrophysics was now possible using radio waves to trace sources of cosmic-rays. We discuss the discovery of extragalactic active galactic nuclei leading to the discovery of quasars and the first evidence for black holes in the nuclei of galaxies. We summarise the present status and future of some of the main radio telescopes used to image the non-thermal emission from external galaxies. Finally, we include a short description of the use of radio signals for the direct detection of cosmic-rays and UHE neutrinos.
first_indexed 2025-11-14T09:32:49Z
format Journal Article
id curtin-20.500.11937-47079
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T09:32:49Z
publishDate 2014
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-470792017-09-13T14:27:26Z Non-thermal radio astronomy Ekers, Ronald © 2013 Elsevier B.V. All rights reserved. This presentation starts with Karl Jansky's discovery of cosmic radio emission in 1933 and notes the striking similarities to Hess's discovery of cosmic-rays in 1912. At first it was assumed that this radio emission was thermal but in 1939 Grote Reber discovered that it was stronger at longer wavelengths, requiring a non-thermal emission process. These discoveries had a revolutionary impact on astronomy and radio astronomy was born. The interpretation of this non-thermal radiation as synchrotron emission from high energy particles in the interstellar medium did not occur until the late 1940s but then it provided the link between radio astronomy and cosmic-ray research. Ginzburg, in particular, saw that cosmic-ray astrophysics was now possible using radio waves to trace sources of cosmic-rays. We discuss the discovery of extragalactic active galactic nuclei leading to the discovery of quasars and the first evidence for black holes in the nuclei of galaxies. We summarise the present status and future of some of the main radio telescopes used to image the non-thermal emission from external galaxies. Finally, we include a short description of the use of radio signals for the direct detection of cosmic-rays and UHE neutrinos. 2014 Journal Article http://hdl.handle.net/20.500.11937/47079 10.1016/j.astropartphys.2013.05.012 restricted
spellingShingle Ekers, Ronald
Non-thermal radio astronomy
title Non-thermal radio astronomy
title_full Non-thermal radio astronomy
title_fullStr Non-thermal radio astronomy
title_full_unstemmed Non-thermal radio astronomy
title_short Non-thermal radio astronomy
title_sort non-thermal radio astronomy
url http://hdl.handle.net/20.500.11937/47079