After the death of a massive, rotating star, ripples in spacetime can rock the universe. These ripples, called gravitational waves, are 15 to 20 times the mass of the Sun.
A new study suggests that instruments on Earth can sense these gravitational waves. And scientists have been waiting a long time to find these new sources.
After running out of fuel, the star explodes. This phenomenon is called collapse, and it leaves a black hole behind a massive disk of remnant material. Matter orbiting a black hole distorts the surrounding space, creating gravitational waves that travel throughout the universe.
Thanks to advanced simulations created by the scientists, the team was able to determine that these gravitational waves could be detected by instruments such as LIGO. Well, that was in a simulation, but if found to be real, the collapsar-driven waves could help scientists understand the mysterious inner workings of collapsers and black holes.
Known sources of gravitational waves are mergers of neutron stars or black holes.
The study was conducted by Ore Gottlieb, a researcher at the Institute’s Center for Computational Astrophysics (CCA) in New York. „One of the most interesting questions in the field is: What are the possible non-collapse sources that could generate gravitational waves that we can detect with current facilities? One promising answer is now „collapsers”.
In the simulation, the scientists replicated the conditions — including magnetic fields and cooling rates — after the collapse of a Massistar’s star. The simulation shows that the collapse can generate powerful gravitational waves that are visible from about 50 million light-years away.
This distance is less than a tenth of the detectable range of high-energy gravitational waves from mergers of black holes or neutron stars, although it is stronger than the uncoupled event so far simulated.
Until now, scientists believed that such waves would be difficult to detect in the background noise of the universe. Instead, gravitational waves from the merger of two objects produce clear, strong signals, like an orchestra playing together.
That’s because two compact objects dance in a tight orbit, creating gravitational waves at every turn as they get closer to merging. This method of almost precise waveforms amplifies the signal to detectable levels. The new simulations demonstrated that, like small objects orbiting in mergers, the rotating disks around the collapsers are „capable of emitting actively magnified gravitational waves,” Kohl said.
„I thought the signal would be very confusing, because the disc is a continuous distribution of gas with material rotating in different orbits. We found that gravitational waves are emitted from these discs, and they are called „she-strong”.
The new work calculated gravitational wave signatures for several possible collapse events. However, stars span a wide range of mass and rotation profiles, which can produce differences in the calculated gravitational wave signals.
Got it,” Lip says, „In theory, we would ideally simulate 1 million collapsers to generate a common template, but unfortunately, these are expensive simulations. So, for now, we have to choose other strategies.
Detecting collapsar-generated gravitational waves could help scientists better understand the internal structure of a star during collapse and help determine the properties of black holes – two Tobyunderstood as cs u” to be bad.
„These are things we would otherwise „undetect.” „Got it” dear He says. „The only way to probe these inner stellar regions around a black hole is through gravitational waves.”
Journal Note:
- simoOre Gottlieb, Amir Levinson and Yuri Levin. Cooled Collapser Disks. Astrophysical Journal Letters. DOI 10.3847/2041-8213/ad697c