کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1770593 1523372 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Non-thermal radio astronomy
ترجمه فارسی عنوان
نجوم رادیویی غیر حرارتی
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم نجوم و فیزیک نجومی
چکیده انگلیسی


• The history of discoveries in radio astronomy.
• Comparing the discovery of cosmic rays by Hess and cosmic radio emission by Jansky.
• Interpreting cosmic non-thermal radio emission as synchrotron radiation.
• Using radio waves to trace the sources of cosmic rays in galaxies and quasars.
• The present status and future developments of imaging radio telescopes.
• Using radio telescopes as UHE cosmic ray and neutrino detectors.

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.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Astroparticle Physics - Volume 53, January 2014, Pages 152–159
نویسندگان
,