75 scientists, using NASA’s Neil Gehrels Swift Observatory, have discovered a black hole that is continuously eating away at a star similar to our Sun. Located in a galaxy about 500 million light-years from Earth, the black hole continuously gnaws at the star, a phenomenon known as a tidal disruption event, creating a bright burst of light. This burst of light then illuminates the galaxy, allowing its exploration. The black hole and tidal disruption event – known as Swift J023017.0+283603, or Swift J0230 for short – is only part of this story, as the discovery was made using data analysis Swift’s revolutionary new. X-ray telescope (XRT) equipment. This technique will usher in a new era of science with Swift, a three-telescope space observatory designed to observe high-energy cosmic phenomena at multiple wavelengths.
“The hardware, software and skills of Swift’s international team have helped it adapt to new areas of astrophysics throughout its lifetime. Neil Gehrels, the mission’s namesake, oversaw and encouraged many of these transitions. Now, with this new capability, it’s generating even more exciting scientific research,” said Swift team member and lead author Phil Evans from the University of Leicester. So what exactly is tidal disruption? As mentioned, a tidal disruption event is a cosmic phenomenon that occurs when a star orbits too close to a black hole. When the star approaches the black hole, the immense gravitational forces from the black hole create extreme tides that tear the star apart into a long, thin stream of gas and other cosmic material. One edge of this stream of gas swings around into the black hole while the other end gets thrown out of the system as a whole.
When a tidal disruption event occurs, multi-wavelength flashes of light are created when the gas stream interacts with a disk of material orbiting the black hole. Scientists will then look for these eruptions to study the system’s characteristics, scale, and more. Additionally, scientists used the characteristics of the star and black hole to determine the emission levels they saw during the event, allowing them to create a variety of scenarios and behaviors that could be used to Classification of tidal disruption events.
However, not all tidal disruption events result in immediate destruction of the star. Sometimes a star orbits a black hole at a distance where tidal forces are not strong enough to completely destroy the star but still capture gas and matter. The star will continue to orbit the black hole until it loses too much gas and matter and eventually disintegrates. These events are called partial tidal disturbances or repeated tidal disturbances, and Swift J0230 is one such event. Other examples of repeated tidal disruptions include an event in which an energetic burst occurred every 114 days, possibly caused by a star orbiting a black hole 78 million times more massive. Our sun causes it. Another recurring intermittent event saw bursts of energy every nine hours from a black hole with the mass of 400,000 Suns. Swift’s XRT first observed Swift J0230 on June 22, 2022. The instrument noticed a bright flash of light coming from a galaxy 500 million light-years away in the constellation Triangulum. After the first observation of the flare, XRT continued to observe the galaxy and recorded nine more flares every few weeks.
Evan et al. I think Swift J0230 is a good candidate for a recurring tidal disruption event, in which a star similar to our Sun is repeatedly sucked in by a black hole nearly 200,000 times the mass of the Sun. our heaven. The team estimates that the star loses about three Earth’s mass of gas and material each time it gets closer to the black hole. When Swift J0230 was first observed by XRT, scientists were not immediately convinced by the idea of a repeating tidal disruption event. That’s right, teams examined Swift’s optical/ultraviolet telescope equipment but found nothing, meaning the event emitted only X-rays. “We searched and clarified the event in data collected by the Swift Ultraviolet/Optical Telescope. But there’s no sign of that. Swift team member Alice Breeveld of the Mullard Space Science Laboratory at University College London said the galaxy’s variability is entirely in X-rays. This helps rule out other potential causes. While several other recurring tidal disruption events have been observed, the content of Swift J0230 allows scientists to model and compare how different types of stars interact with black holes. vary in size during repeated tidal disruptions.
The discovery of Swift J0230 was only possible thanks to a new XRT data analysis program called Swift X-ray Transient Detector, which was developed by Evans and provides scientists with an automated catalog of all XRT observations. When XRT observes a portion of the sky, the data collected by the instrument is immediately sent back to Earth. When the data reaches the ground, the program automatically compares it with previous XRT observations of the same part of the sky. If the program notices that the X-rays have changed, it will immediately alert scientists, allowing them to quickly coordinate additional observations of that region of the sky. This is what happened to Evans et al. during the discovery of Swift J0230 and demonstrated that the program is a useful tool for scientists interested in studying high-energy cosmic phenomena such as tidal disruption events. “Swift J0230 was discovered just about two months after Phil launched his program. This bodes well for the detector’s ability to identify other transient events and for Swift’s future in exploring new scientific spaces,” said Swift principal investigator S. Bradley Cenko of the Goddard Space Flight, NASA Center, said.
source: https://www.nature.com/articles/s41550-023-02073-y