Listening for sounds from the far corners of space

Listening for "sounds" from the far corners of space
by Doug Hensley
Lubbock, TX (SPX) Aug 22, 2023

Scientists spectacularly confirmed the existence of gravitational waves several years ago, but now they are searching the cosmos for new and different types of these waves that result from different objects in deep space.

Benjamin Owen, a professor in the Department of Physics and Astronomy at Texas Tech University, was recently awarded a three-year National Science Foundation (NSF) grant that aims to uncover and confirm additional types of gravitational waves.

"So far with gravitational waves we've seen what happens when you have two black holes and/or neutron stars spiraling together and merging," Owen said, referring to the scientific breakthrough that occurred in 2015 with confirmation of the waves. "There are new types of gravitational waves that have not been detected yet, but we know they are out there at some level."

Part of Owen's research is in done within the Laser Interferometer Gravitational-Wave Observatory (LIGO) Scientific Collaboration, a scientific community dedicated to studying and expanding knowledge about gravitational waves. His research also is connected to the current work of Alessandra Corsi, a colleague in the same department.

"The best-case scenario would be that we find one or more of these new gravitational-wave signals in the next year or so," Owen said. "That would be great because it would give us the opportunity further understand how neutron stars live in the universe and how they evolve. These new kinds of waves would tell us things the current signals don't."

Gravitational waves were predicted by Albert Einstein in his theory of relativity more than a century ago. When their existence was confirmed, it opened an entirely new field of scientific exploration that probes the extremes and the origins of the universe.

"Neutron stars are the most extreme form of matter in the modern universe," Owen said. "We have learned a lot about them through various other means, but gravitational waves opened a new window looking directly inside them. Basically, the matter in the core of a collapsing star, when it's squished down to this incredible density, causes things to happen that you don't see anywhere else in the universe since the Big Bang."

The NSF grant will allow Owen to learn more about neutron stars and what takes place in their interiors to produce these different types of waves, one of which is characterized by short bursts and the other as more continuous and longer-lived. It also will prepare the way for an eventual transition from LIGO to Cosmic Explorer, a new detector expected to become fully operational in approximately 15 years.

"By the time of Cosmic Explorer, we hope to see a number of these other types of signals from neutron stars," Owen said. "There will be a more sensitive detector, and we will get more information on what's going on in the far corners of the universe as far as some of the crazy things that can happen to matter."

The research conducted now will help lay important groundwork for the future.

"The idea is, as the grant continues, we test basic searches on LIGO data, maybe find something, and develop better techniques that will take advantage of better data and extract more information," he said. "Cosmic Explorer is approximately 15 years out, but what we do today makes the scientific case for what we ought to see and what we can learn, not just to improve the experiment, but to improve the mathematics and programming to use it to its fullest capability."