Colloquium:- Neutron stars- Strongest Magnets in the Universe
A massive star ends its life as a violent supernova explosion. The compact core left over could form a neutron star. Such stars are ultra-dense objects, with more massive than the Sun but a size smaller than a city. They rotate rapidly and possess the strongest magnetic field in the Universe. These remarkable properties make them ideal laboratories for studying physics under extreme conditions, such as ultra strong gravity and extreme electromagnetism, that can never be reproduced on Earth.
In this talk the speaker will give a general overview of neutron stars and focus on effects of magnetic fields. Specifically, he will highlight some recent observational results of pulsar wind nebulae and magnetars. The former are synchrotron nebulae resulting from the interatction between neutron star’s magnetized outflow and the surrounding environment. These are important local acceleration sites of cosmic rays in our galaxy. Magnetars are the most extreme class of neutron stars that can have a surface magnetic field strength up to 10^15G, and occasionally exhibit violent radiative outbursts. The speaker will discuss the idea to unify magnetars with other classes of neutron stars.
講者：Prof. Stephen NG Chi Yung 吳志勇 教授(香港大學物理系)