Researchers from the California Institute of Technology (Caltech) ran simulations and found a way to measure the rotation speed of dying stars before they go supernova.
Every century, about 2 stars on average in our galaxy explode, turning into a supernova. These eruptions send streams of elementary particles called neutrinos in our direction, creating multiples in space-time, called gravitational waves. About 1,000 supernovae have already erupted in distant regions of the Milky Way, and scientists are waiting for the neutrinos and gravitational waves that should come from them.
On Earth, neutrino detectors and gravitational wave detectors can detect signals, which will provide information about the massive bodies from which they came. If the scientists want to decipher the information, they need to know in advance how to analyze the data that will be received by the detectors. Precisely for this purpose, researchers from the California Institute of Technology (Caltech) ran computer simulations of supernova explosion events. And one of their conclusions was that if the dying star's core spins rapidly before it explodes, the neutrino particles and the resulting gravitational waves will have the same oscillation frequency.
"We saw this correlation in the results from the simulation and were completely surprised," says Professor Christian Ott, the lead researcher. "In the signals of the gravitational waves, an oscillation is obtained even in the state of slow rotation. But if the star rotates at a high speed, similar oscillations can be observed both in the neutrino particles and in the gravitational waves, according to which it is possible to conclude about the rotation speed of the star before its eruption."
Scientists still do not know all the details that cause a massive star (about 10 solar masses or more) to go supernova. What they do know is that when such a star consumes all its fuel, it can no longer resist its gravitational pull, and it begins to collapse in on itself, in the process turning it into a proto-neutron star. Now the scientists also know that during the event, another force, the strong nuclear force, takes over and causes shock waves that tear apart the stellar core. But these shock waves are not energetic enough to cause the explosion itself.
The researchers speculate that there is a "supernova mechanism" that causes the star to explode. The current theory offers several options. According to one of them, it is possible that the neutrons absorb the shock waves and refuel them. According to another theory, the proto-neutron star rotates at high speed, and becomes a kind of "dynamo". In doing so, he creates a magnetic field that creates an energetic jet that erupts from the poles. This causes the shock waves to increase and eventually leads to an explosion. According to the new correlation found in the experiment, Ott's team was able to find a way to determine whether the rotating core of the star plays a significant role in the supernova explosion.
It is not easy to collect information about a dying star through observations (for example with a telescope), because the observations give information about the surface of the star, and not about the internal composition. On the other hand, neutrinos and gravitational waves are emitted from the core of the star, and they do not even come into contact with other particles while being ejected into space at the speed of light.
The neutrinos' ability to pass through matter, and interact only through the weak nuclear force, makes them nearly undetectable. However, neutrinos have already been detected before: neutrinos from supernova 1987a in the Large Magellanic Clouds were detected in 1987. If a supernova had erupted in the Milky Way, researchers estimate that neutrino detectors would have detected about 10 particles. In addition, today there are gravitational wave detectors (such as MIT's LIGO), which can detect such waves.
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It seems to me that Yael Petar meant to write: "... folds in space-time, called gravitational waves.."
And she got it. The rest of the article is very interesting.
for my time
Even if you flirt with a deer with most of your knowledge
Please keep your manners and modesty
It won't detract from your words
Thanks.
I answered
It's nice that you want to open my mind, but it doesn't change the correct things I wrote before.
In the article you sent it is clearly stated that: "We haven't found strange stars yet," Jaikumar explains
That is, there is no observational evidence for the existence of quark stars - which is not surprising, among other things because they will probably behave quite similarly to neutron stars. I'm not saying that there are or aren't any, it's really not my field and therefore it's not right to have positions on the subject. All I know is that in the meantime:
1. We don't know how to deal with the strong force acting among other things than a number of nucleons and therefore it is not possible to deal with such questions properly.
2. In addition, and as part of this, they do not know how to write down equations of state of degenerate material under such pressures.
Therefore, it really doesn't surprise me that they don't know whether such stars exist or not, and when someone writes inaccurate things on the website that may create incorrect understandings among readers, it is important to refer to them and for that purpose, Wikipedia is a good source that summarizes the main points of the news as of today.
deer,,
Instead of summarizing and summarizing the values of Wikipedia, it is something that will open your mind
http://www.dailygalaxy.com/my_weblog/2011/09/image-of-the-day-strange-quantum-star-found-in-supernova.html
I answered
I think you are wrong in the nomenclature. A neutron star can never have a mass of about 100 solar masses. In fact, the heaviest neutron star discovered so far has a mass of only two solar masses:
https://www.hayadan.org.il/sciencedaily-your-source-for-the-latest-research-news-and-science-breakthroughs-updated-daily-science-news-share-blog-cite-print-email-bookmark-astronomers-discover-most-massive-neutron-star-0811101/
It is known that a core with a mass above 3 solar masses is expected to collapse into a black hole and not a neutron star (Tolman-Oppenheimer-Volkoff limit) - by calculating simple orders of magnitude, you get exactly the mass of Chandraskar (1.4 solar masses) and the increase to 3 solar masses results from considering the ratios general
I assume you mean that neutron stars originating from a normal star that has a mass of more than 100 solar masses are in a quark gluon plasma state. So like this:
A. Stars with 100 solar masses are well beyond the limit that under normal circumstances becomes a black hole rather than a neutron star. There are arguments about the exact limit, but all talk revolves around the order of magnitude of about 10 solar masses.
B. As for the gluon plasma state - this is a theoretical state that should exist at high enough energies (high enough to break the nucleons into quarks). This situation may be created in massive neutron stars, but in the meantime there is no evidence for this and there is really no consensus about it. By the way, this is what is called "quark stars".
heat
No, it's not possible to link gravitational waves.. I think.. or maybe it's not allowed at all... what do you think? Maybe it's not possible to link gravitational waves at all? )
Has anyone even seen gravitational waves
Can I link?
It is possible that there are several different types of neutron stars with different cores, which is determined mainly by the mass but also by the rotation
In heavy neutron stars up to 100 solar masses the core is liquid/gas like in a state called quark gluon plasma.
Neutron stars may exist that contain the "strange" quark in large quantities
As far as I know, gravitational waves have not yet been discovered and measured, so everything here is still in theory.
The statement in the article should also be explained: "About 1,000 supernovae have already erupted in distant regions of the Milky Way, and scientists are waiting for the neutrinos and gravitational waves that should come from them." End quote.
For the milk since its existence, more than a thousand super novae have exploded!
The intention is apparently that:-
In the last fifty thousand years, about a thousand super novae (one every fifty years) have exploded in the Milky Way, which we have not yet seen on Earth because of their distance. It would be good to know how to guess which of the 100 billion stars is going to go super nova and research about it even before seeing the explosion.
Good day and good luck to the researchers
Sabdarmish Yehuda