天文学奖
2023

2023年度邵逸夫天文学奖平均颁予马修・贝尔斯（Matthew Bailes）、邓肯・洛里默（Duncan Lorimer）和莫拉・迈克劳克林 (Maura McLaughlin)，以表彰他们发现快速电波爆发 (FRBs)。马修・贝尔斯是澳洲研究委员会 (ARC) 引力波发现卓越中心主任。邓肯・洛里默是美国西维珍尼亚大学物理及天文学系教授暨临时系主任及埃伯利文理学院研究副院长。莫拉・迈克劳克林是美国西维珍尼亚大学物理及天文学埃伯利家族杰出讲座教授暨引力波及宇宙学中心主任。

快速电波爆发是天文学中最极端、最神秘的现象之一：它们是一种强烈的射电爆发，在千分之几秒之内释放相当於太阳数天辐射的能量。它们的爆发源比地球细小，处於非常遥远的星系中。贝尔斯、洛里默、迈克劳克林 (与合作伙伴纳尔凯维奇和克劳福德) 在2007年发表开创性研究论文，描述发现了首个快速电波爆发，并推断出其来源的多项特性，特别是它的极远距离、细小尺寸和巨大能量，他们还在论文中估计了快速电波爆发在宇宙中产生的速率，并强调它们可以用来探测宇宙的潜在功能。

Pulsars are among the most remarkable and exotic objects in the heavens: rapidly spinning neutron stars with a mass similar to the Sun’s, diameters of only a few tens of kilometers and magnetic fields a million million times stronger than the field we experience at the surface of the Earth. Pulsars emit beams of radio waves from their magnetic poles, which sweep across the Earth as the pulsars spin; these periodic pulses can be detected by Earth-based telescopes. On August 24 2001, during a search for pulsars in nearby galaxies, a telescope at the Parkes Observatory in Australia recorded a brief but unusually strong burst of radio emission. This event lay undetected in the archives of that search for more than half a decade, until it was found by David Narkevic, a student working with Duncan Lorimer and Maura McLaughlin at West Virginia University on a search for single pulses from pulsars with strongly variable radio emission. The arrival time of the burst was dispersed, that is, it changed with frequency, a characteristic of astrophysical signals such as those from pulsars that have propagated through the plasma of ionized gas that fills much of our Milky Way and other galaxies. However, the dependence of arrival time on frequency was far larger than for any known pulsar. Lorimer, McLaughlin, Bailes and their collaborators recognized that this dependence implied that the mysterious source – now known as the “Lorimer burst” – lay far outside our own Milky Way, roughly 100,000 times further than the typical pulsar and so far away that the burst was emitted over a billion years ago. They also showed that despite this enormous distance and the correspondingly huge energy requirements, the object emitting the burst had to be very small – the finite speed of light and the short duration of the signal implied that the burst must have come from a region smaller than the Earth.