Leicester scientists describe astronomical phenomenon never witnessed before

Researchers from our University have contributed to a simultaneous global announcement -  in London, Washington DC, and Munich  -  of the discovery and results from the joint detection of gravitational waves and light from the collision of a pair of mutually orbiting neutron stars.

Their research includes the earliest detection of a pulse of ultraviolet light with the Swift satellite, signalling the emergence of a neutrino–irradiated wind in addition to the ejection in the orbital plane of material rich in the heaviest elements, such a gold and platinum.

In addition, Hubble Space Telescope spectral results demonstrate the presence of these very heavy elements, with images in which the light is seen to fade from blue to red as the heavy element ejecta are spun out of the collision.

Professor Julian Osborne, from our Department of Physics and Astronomy, said: “This is a very major science story, in which scientists at the University of Leicester have played a highly significant role. More than 30 research papers have been published at the time of these briefings in Germany, UK and the US. One of these, giving an overview of all the astronomical follow-up observations, has around 3,500 authors from around 1,000 institutions.  There are 15 papers by University of Leicester co-authors so far.”

The first detection of gravitational waves, made on 14 September, 2015 and announced on 11 February, 2016, was a milestone in physics and astronomy; it confirmed a major prediction of Albert Einstein’s 1915 general theory of relativity, and marked the beginning of the new field of gravitational-wave astronomy. The UK played a leading role in that detection and key technological and computing advances were made in the UK which enabled the historic first detection.

Since then, there have been three more confirmed detections, one of which (and the most recently announced) was the first confirmed detection seen jointly by both the LIGO and Virgo detectors. In addition the 2017 Nobel Prize for Physics was last week awarded to the team behind the gravitational waves breakthrough.

The published articles announcing LIGO’s first confirmed detection, second confirmed detection, and third confirmed detection have been cited more than 1,700 times (total), according to the Web of Science citation counts. A fourth paper on the three-detector observation was published on October 6; a manuscript was made publicly available on September 27.

Contributions from Leicester included:

  • At the Royal Society in London, a media briefing was managed by the Science and Technology Facilities Council, and led by the Astronomer Royal, Lord Martin Rees.  It included Dr Phil Evans  from the University of Leicester who is the lead author of a substantial paper in the prestigious journal ‘Science’ that was released at the time of the briefing.
  • In the UK, in addition to the Royal Society event, Professor Osborne was present at the BBC’s Broadcasting House to offer interviews and comment on the announcements.
  • At the National Science Foundation, in Washington DC in the USA, Professor Nial Tanvir from the University of Leicester presented the results of his paper appearing in the Astrophysical Journal.
  • At the European Southern Observatory in Munich, Germany, the media briefing presented results from their observatories. Some of this work has University of Leicester co-authors.