Researchers using BICEP2 at the South Pole claimed to have detected gravitational waves in March this year. This would have been direct evidence of cosmic inflation; the smoking gun for the Big Bang. Recently, those results have come under fire, and even the researchers admitted they can’t rule out the possibility that the signal they detected was actually dust from the Milky Way.
Inflation isn’t the only thing believed to cause gravitational waves, however, and a team composed of members from Monash University and the University of Warwick believe they are exceedingly close to proving their existence based on observations of a neutron star. The researchers were led by Duncan Galloway of Monash University, and the paper is published in The Astrophysical Journal.
Gravitational waves were first proposed by Albert Einstein back in 1916 as part of his theory of general relativity, which describes how mass affects space-time. Detecting these has been quite difficult, as their sources are very distant to Earth and the ripples smooth out considerably before they are able to reach our detection equipment, creating an incredibly weak signal.
The research is centered on Scorpius X-1, a binary system that is composed of a neutron star and the companion star from which it feeds. The system is located about 6,000 light-years away in the constellation Scorpius. Aside from our Sun, it is the strongest source of x-rays in the sky. Though Scorpius X-1 isn’t the most proximal neutron star to Earth, the strong x-ray signal makes it a good target for study.
The team utilized data collected by the William Herschel Telescope at La Palma, Canary Islands as well as the Very Large Telescope. In their current paper, the team describes how they were able to enhance the precision of Scorpius X-1’s orbit by a factor of two; a marked improvement. Determining the orbit and other measurements are significant factors in locating the gravitational waves the neutron star is believed to produce.
"We have made a concerted effort to refine Scorpius X-1's orbit and other parameters, with the goal of significantly boosting the sensitivity of searches for gravitational waves," Galloway said in a press release.
"Detecting gravitational waves will open a new window for observation and allow us to study objects in the universe in a way that can't be achieved using traditional astronomy techniques.”
The team will continue along this line of research. The ability to detect and study gravitational waves will allow scientists to improve models and test some of the most fundamental aspects of physics.