|COOKIES: By using this website you agree that we can place Google Analytics Cookies on your device for performance monitoring.|
The history of radio astronomy polarisation measurements
If you have a question about this talk, please contact David Titterington.
While intensity of electromagnetic radiation (radio, infrared, light, or X-ray) gives us primary information about the distribution of the baryonic matter in the Universe, polarisation is a parameter that enables us to investigate many additional details. Polarisation at radio frequencies gives us details of emission processes since the non-thermal synchrotron process dominates at low radio frequencies in emission regions. The studies can be inverted and by means of polarisation observations the details of Cosmic Magnetic Fields in the emission regions can be delineated. The Zeeman Effect is based on polarisation observations and gives a method of direct determination of magnetic field. In addition polarised radio sources can be used as probes of the intervening medium through which the radio waves are propagated. Faraday Rotation effects are observed and in conjunction with known thermal emission can be used to determine magnetic fields. Some of the earliest radio polarisation observations were made in Cambridge in 1960-1963. For me the year 1963 was crucial: my PhD examination. From these early beginnings a whole research area has developed: the study of Cosmic Magnetic Fields. I will describe the technology needed for polarisation observations and show the early observations but in addition I will follow the developments up to the present day.
This talk is part of the Cavendish Astrophysics Seminars series.
This talk is included in these lists:
Note that ex-directory lists are not shown.
Other listsNatural History Cabinet, Cambridge University Department of History and Philosophy of Science al769's list MRC Epidemiology and CEDAR Seminars
Other talksSecond Annual Public Lecture in Medieval and Early Modern Slavonic Studies: "Church Union and Ritual: The Confrontation of Latin Theology and Eastern Orthodoxy" Feeling untouched: space, emotions and untouchability Indian Monsoon: Trends, Rhythms and Thresholds since Eocene TBA Challenging bariatric care practices and fat stigma in ICU A solid state conceptualization of information transfer from gene to message to protein