Ripples in spacetime caused by the death of massive rotating stars may be within the detection limits of projects like lego And the virgin.
Collapsed stars, the remains of massive stars that have collapsed, may produce detectable images. Gravitational wavesAccording to a new simulation, these waves, which originate from material flowing into black holes, could provide insights into the internal processes of stars and black holes, although identifying them remains a challenge.
Gravitational waves from dying stars
The death of a massive, rapidly spinning star could shake the universe. And the resulting ripples—known as gravitational waves—could be felt by devices on Earth, according to new research published Aug. 22 in the Astronomical Journal. the Astrophysical Journal LettersThe scientists conducting the research expect that these new sources of gravitational waves are still waiting to be discovered.
Gravitational waves are created after the violent deaths of rapidly rotating stars 15 to 20 times the mass of the Sun. When they run out of fuel, these stars explode, then implode, in an event known as a stellar collapse. This leaves behind Black hole Surrounding it is a large disk of leftover material that is rapidly spinning in the black hole’s mouth. The rotation of the material – which lasts only a few minutes – is so strong that it distorts the space around it, creating gravitational waves that travel through the universe.
Simulation showing the distribution of matter around a newborn black hole after a stellar collapse. Warmer colors indicate higher density of matter. Copyright: Ore Gottlieb
Gravitational Wave Detection Simulation
Using sophisticated simulations, scientists have determined that these gravitational waves could be detected with instruments such as the Laser Interferometer Gravitational-Wave Observatory (LIGO), which made the first direct observations of gravitational waves from black hole mergers in 2015. If the collapse-driven waves are detected, they will help scientists understand the mysterious inner workings of collapses and black holes.
“Currently, the only sources of gravitational waves that we have detected come from the merger of two compact objects—neutron stars or black holes,” says Or Gottlieb, a researcher at the Center for Computational Astrophysics at the Flatiron Institute in New York City. “One of the most interesting questions in this field is: What are the possible non-merger sources that could produce gravitational waves that we can detect with current facilities? One promising answer right now is stellar collapses.”
Gravitational waves that can be detected from collapsing stars
Gottlieb, along with visiting CCA researcher and Columbia University professor Yuri Levin and Tel Aviv University professor Amir Levinson, simulated the conditions — including magnetic fields and cooling rates — that would exist in the aftermath of the collapse of a massive rotating star. The simulations showed that collapsing stars could produce gravitational waves powerful enough to be visible from about 50 million light-years away. That’s less than a tenth of the detectable range of more powerful gravitational waves from black hole or neutron star mergers, though it’s still stronger than any non-merger event simulated to date.
Unexpected results in gravitational wave patterns
The new results came as a surprise, Gottlieb says. Scientists thought that chaotic collapse would create a jumble of waves that were hard to discern amid the cosmic background noise. Imagine an orchestra getting ready to play. When each musician plays his or her own notes, it can be hard to tell which tune is coming from a single flute or tuba. Gravitational waves from the merger of two objects, on the other hand, create signals that are as clear and powerful as an orchestra playing together. That’s because when two compact objects are about to merge, they dance in a tight orbit that creates gravitational waves with each spin. The nearly identical rhythm of the waves amplifies the signal to a detectable level. The new simulations showed that rotating disks around collapsing stars could also produce gravitational waves that amplify together, just like the compact objects orbiting in mergers.
The power of waves driven by the coulombs
“I thought the signal would be more chaotic because the disk is a continuous distribution of gas with material rotating in different orbits,” Gottlieb says. “We found that the gravitational waves from these disks are emitted coherently, and they are also quite strong.”
Not only is the predicted signal from collapsing disks strong enough to be detected by LIGO, Gottlieb’s calculations suggest that some events may already be present in existing data sets. Proposed gravitational wave detectors like the Cosmic Explorer and the Einstein Observatory could detect dozens of them each year.
Crash event detection strategies
The gravitational wave community is already interested in searching for these events, but it’s no easy task. The new work has calculated gravitational wave signatures for a modest number of possible stellar collapse events. However, stars span a wide range of mass and rotation patterns, which should create variations in the calculated gravitational wave signals.
“In principle, it would be better to simulate a million collapsing stars so that we can create a general model, but unfortunately, such simulations are very expensive,” says Gottlieb. “So now we have to choose other strategies.”
Scientists could look at historical data to see if there have been any events similar to the one Gottlieb simulated. But because stars are so diverse, each one carries a potentially unique signal, and scientists are unlikely to find a match for one of the simulated signals. Another strategy is to use other signals from nearby collapse events—such as supernovae or gamma-ray bursts emitted as a star collapses—and then search the data archives to see if any gravitational waves were detected in that region of the sky around the same time.
Implications for Understanding Black Holes
Detecting gravitational waves from a collapsing star would help scientists better understand the internal structure of a star as it collapses, and would also enable them to learn about the properties of black holes – two subjects that are still poorly understood.
“These are things we can’t detect any other way,” Gottlieb says. “The only way we can study these inner stellar regions around a black hole is with gravitational waves.”
Reference: “In the Crosshairs of LIGO? Strong Coherent Gravitational Waves from Cooled Collapsar Disks” by Ore Gottlieb, Amir Levinson, and Yuri Levin, August 22, 2024, Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ad697c
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