Astronomers may soon discover extreme objects that continuously produce gravitational waves

The cosmic zoo contains objects so strange and extreme that they generate gravitational waves. Scorpius X-1 is part of that weird group. It’s actually a binary pair: an orbiting neutron star with a low-mass stellar companion called V818 Scorpii. The pair provide a prime target for scientists looking for so-called “persistent” gravitational waves. These waves must exist, although none have been detected – yet.

“Scorpius X-1 is one of the most promising sources for detecting these persistent gravitational waves,” said Professor John Whelan of the Rochester Institute of Technology’s School of Mathematical Sciences. He’s the Principal Investigator of the RIT Group at the LIGO Scientific Collaboration, and is part of a group of scientists focused on the direct detection of gravitational waves. LIGO is a Laser Gravitational-Wave Observatory, located in Washington and Louisiana. Virgo (in Italy) and KAGRA (in Japan) are also looking for gravitational waves, often in conjunction with LIGO.

The search for gravitational waves in Scorpius X-1

Whelan’s team used data from the third round of LIGO-Virgo observations in their search for persistent gravitational waves from Scorpius X-1. “It’s relatively close to only 9,000 light years “Away,” Whelan said. And we can see it very clearly in x-rays because the gaseous substance is from Companion star on the neutron star.

Despite its brightness, the team did not detect the constant washing out of gravitational waves from Scorpius X-1. This does not mean that waves do not exist. In fact, their data provides important targets as they plan further observations of the pair. It helped them improve their research methodology and should eventually lead to the discovery of these elusive waves.

“This research has yielded the best constraint to date on the potential strength of gravitational waves emitted by Scorpius X-1,” said Jared Wofford, Ph.D., Astrophysical Sciences and Technology. candidate. For the first time, this research is now sensitive to models of the system’s potential torque-equilibrium scenario, which states that the torques of the gravitational wave and the accretion of matter on the neutron star are balanced. In the coming years, we expect even better sensitivities from more data obtained by LIGO’s advanced observations are looking deeper into the torque equilibrium scenario in hopes of making the first continuous wave detection.”

Scorpius X-1 system

Scorpius X-1 is the most powerful X-ray source in our sky (after the Sun). It was discovered by astronomers in 1962 when they sent a sounding rocket with an X-ray detector into space. Over the years, they’ve discovered that the powerful X-ray emissions come from a 1.4-solar-mass neutron star that’s gobbling up material flowing from its smaller 0.4-solar-mass companion. The strong gravitational field of a neutron star accelerates interstellar matter as it falls on the star. This heats up the matter and causes it to emit x-rays.

While the system is a strong emitter of X-rays and is bright in optical light, it is actually classified as a low-mass X-ray binary. The two objects have an orbital period of 18.9 hours. It is not clear if they formed together earlier in their history. Some astronomers suggest that they could have met when a massive star met its young companion closely in a globular cluster environment. The larger companion eventually exploded as a supernova, creating the neutron star.

Using gravitational waves to understand the Scorpius X-1 binary pair

Most of us are familiar with the gravitational waves generated by the merger of black holes and/or neutron stars. The first detection of these waves occurred in 2015. Since then, LIGO and its sister facilities KAGRA and Virgo have detected these “stronger” waves regularly. It’s important to remember that these detections record specific collisions – essentially “one-off” events. However, they are not the only sources of gravitational waves in the universe. Astronomers believe that massive objects spinning hundreds of times per second — such as neutron stars — can produce weaker, detectable continuum waves.

So, what might be causing the waves in a neutron star/companion star binary pair? Look at the outer structure of neutron stars. Scientists describe them as uniformly smooth objects, with strong gravitational and magnetic fields. However, they can have small surface irregularities (called “mountains”). These stick out only fractions of a millimeter above the surface of the neutron star’s “shell”. The mountains are really distortions in that crust. They are created by intense pressures in the neutron star’s electromagnetic field.

It is also possible for these deformities to occur when the body’s rotation slows down. Or maybe when it suddenly sped up. However they are formed, they influence the neutron star’s magnetic and gravitational fields. This may be what is causing it gravitational waves. If so, those mountains may be small, but their impact could be huge.

The challenge now is to measure those waves. Recently, Astronomy scientists It will detect a continuous “wash” of waves coming from Scorpius X-1. Their data will tell them more about neutron star itself. It should also give clues to the dynamics of a binary pair as the members rotate in relation to each other.