The cosmic radio wave AT2019dsg, discovered in 2019, is said to be high-energy neutrinos commonly known as “ghost particles” made up of black holes that split stars.Research guidelines published in the journal Astrophysics at the beginning of the monthAfter analysis, the AT2019dsg is so normal that at least until the black hole is torn apart, the energy it emits is not enough to create “ghost particles”.
AT2019dsg was first discovered on April 9, 2019 from a galaxy 750 million light years away. X-ray and radio observations confirmed that it came from a miraculous black hole, whose mass was 30 million times that of the Sun, and that once emitted dazzling light a tidal event (TDE).
To tear a star, the star is first held close to the black hole by the gravitational pull of the black hole; The largest wave force of the black hole first stretches and then pulls to tear the star. TDE refers to the process of tearing up a black hole star. Half of the decayed star emits light as it rotates into a disk around the black hole, and generates great heat and light before the event is pulled out of the horizon; Other star fragments were thrown into existing space.
Tearing a star The star is near the black hole
Nearly 6 months after the appearance of AT2019dsg, on October 1, 2019, the IceCube Neutrino Detector at the South Pole detected the neutrino IC191001A with an energy level of more than 200 tera electronvolts.
Neutrinos (neutrinos) are called “ghost particles” because they have an almost zero mass, can fly at speeds close to the speed of light, and do not actually interact with ordinary things; However, sometimes neutrinos interact, and this also works. The detector digs deep tunnels in the ice layer and makes the flashes more prominent.
Depending on the light scattering pattern and the properties of the luminosity, scientists can calculate the energy level of neutrinos and the direction of their source. Previously, IC191001A was said to come from the AT2019dsg direction, so scientists calculated that the probability that neutrinos had no contact with this TDE was only 0.2%.
However, the argument raises some major issues.Yevd Sentes, astronomer at the Harvard Astronomy Center, who led the research, questionedIf this neutrino came from AT2019dsg in some way, why didn’t the academic world find a supernova related neutrino this far or near? Because the latter is more common and has the same energy velocity.
Neutrino energy can be calculated from light scattering and brightness
The Sentes-led research team used Chile’s Atacama Large Millimeter / Sub Millimeter Array (ALMA) to see AT2019dsg on radio wavelengths for more than 500 days, and found that TDE was bright at radio wavelengths for about 200 days, after which it slowly began to darken.
The group also calculated the total amount of energy emitted from TDE, which is similar to the energy released by the Sun over 30 million years, falling within the range of constant emissions of TDE and type Ib and Ic supernovae.
However, to produce neutrinos with the same high energy as IC191001A, the exit energy must be about 1,000 times larger. In addition, the energy flow must have a strange geometric shape, which is not compatible with AT2019dsg. In other words, AT2019dsg is more common and may require a new report to explain the origin of IC191001A.
However, humans still have a lot of ignorance about neutrinos and TDE, which means AT2019dsg will continue to receive attention. With the black hole still eating away at the stars, the team could test AT2019dsg again, Sentes added.
Scientific warning, A mysterious ‘ghost particle’ probably did not come from a black hole food16 October 2021
Sentes, Y., Alexander, Katie, Berger, e. And others. (2021) Wave Disruption Event Radio Observations of a Normal Exit from AT2019dsg. Journal of Astronomy Volume 919 No. 2. doi: 10.3847 / 1538-4357 / ac110a
Sentence / Alan Chiu