The historic scientific discovery of 170 scientists from 33 universities in 12 countries: the first tau-type neutrino was apparently observed, appearing among several billions of billions of mu-type neutrinos sent from CERN
The historical scientific discovery of the "Opera" experiment, located in an underground laboratory under the "Gran Sesso" mountain in Italy: 170 researchers from 33 institutions in 12 countries, discovered after seven years of experiment that one of the many billions of muon-neutrinos created in the beam CNGS in the CERN accelerator complex has apparently turned its skin into a tau neutrino and it was observed using the OPERA experimental facility. The scientists say that this is a result of historical scientific importance. Observing a number of additional tau neutrino events within a huge amount of normal neutrino-mu interactions will be the long awaited proof - of a direct conversion of one type of neutrino into another type: the phenomenon known as "neutrino oscillations".
Professor Yaakov Goldberg from the Technion's Physics Faculty, one of the participants in the experiment, explains: "At the beginning of the twentieth century, scientists discovered the phenomenon of radioactivity. There are three types of radioactive materials - alpha, beta and gamma. Beta was identified as a phenomenon of electron emission and the laws of conservation of energy led to the hypothesis that there was another particle that was emitted, not charged with electricity and having a smaller mass than any mass they had been able to measure up to that time. It was called a neutrino. In the middle of the twentieth century, scientists proved its existence in nature experimentally, and so far all attempts to measure mass have given an answer (taking into account the measurement errors) - zero. Various phenomena in nature, which were diagnosed in the last 15 years, led to the hypothesis that the mass is not zero and the "Opera" experiment was designed, built and operated to measure the mass with great precision, much more than what has been measured so far. Now it turned out that the mass is indeed not zero ("close to sure", the researchers disclaim)".
The attached photo shows traces of electrically charged particles in the detector which is the core of the "Opera" experiment. The CERN accelerator in Geneva, which is 730 kilometers from "Opera", emits every 20 seconds a huge amount of neutrino particles (thousands of billions) which are aimed at reaching "Opera". It is located under the Grand Sesso mountain in Italy, 3000 meters below the mountain, on the side of a tunnel built for the highway connecting the west of Italy with the east. Because of its location, the laboratory is shielded from any radiation that originates in space.
The neutrino is not visible in the picture, because it is not electrically charged (this detector can only detect charged particles). Therefore, the neutrino is discovered through the products of its interaction with matter. The neutrino, visible as a yellow dot on the left side of the image, came from CERN. At the yellow dot he hit a nucleus of matter and seven particles came out. One of them, the red one, is very short. It is a type of electron called tau that was discovered in 1975 and its life span is extremely short. Therefore, after a very short path, it decays into a long particle (daughter) and two more photons. 2g is created as the interaction of a photon, which is realized in the form of two electrons. 1g is also an implementation of photon, shorter than 2g. "The very short red particle, which decays into these three things, allows us to assume with 98% certainty (which will be further improved in the future) that the short red line is a tau particle, which was created by a tau-type neutrino (another type of neutrino cannot create a tau particle)," says Professor Goldberg. "Since the CERN facility only emits neutrinos of the "Mio" type, we believe that we have found an example of a neutrino that was emitted at CERN as a Neutrino of the "Mio" type, changed its identity along the way and became a Neutrino of the Tau type. And this is only possible if the mass is not zero. This is a tremendous discovery, since today the entire theory that explains the universe in physics and astrophysics is based on the premise that mass is mathematical zero. Now the theoreticians have to rethink the theoretical foundations of the structure of the universe and the experimentalists have to persist in trying to verify or reject this discovery."
The experiment was inaugurated in 2006, when the first normal neutrinos were observed after traveling a distance of 730 km from CERN in a time interval of about 2.4 milliseconds, at the speed of light. After that, an extremely intensive search began to find the very tiny and very special signal emanating from the tau neutrino.
OPERA carries out its mission through its heart consisting of more than 150,000 small units called "bricks" with a total mass of 1250 tons. Each brick functions as an elaborate photographic camera. Thanks to these bricks, which are built from a multilayer sandwich of lead plates and a special photographic film, OPERA scientists can reveal all the details of neutrino interactions with the help of precise measurement of the particles formed in the interactions inside the bricks of the neutrinos coming from CERN.
OPERA was designed, built, operated and managed by a large team of scientists from around the world: Belgium, Croatia, France, Germany, Israel, Italy, Japan, Korea, Russia, Switzerland, Tunisia and Turkey.
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Great article, and well written. Thank you for posting.
Yes, the article does explain the course of the experiment in detail. The title bothered me so I commented.
I agree that it is important to accurately test the nature of neutrino oscillations, but I still believe that from a historical perspective this is not the main experiment in neutrino research. The Canadian SNO experiment and the Japanese Super-Kamiokanda and KamLAND experiments were in my opinion more important because they provided the first evidence of those oscillations.
lion:
Although the title is misleading, the content tells exactly what happened and why it is important.
The advantage of this experiment over what was previously observed is the fact that it is a controlled experiment where they knew exactly which neutrino was being produced and showed that the neutrino really changed its skin.
I think there is a mistake in the title because the tau neutrino was discovered already in 2000:
http://physicsworld.com/cws/article/news/2807
In the Opera experiment, neutrino oscillations were observed - a ion neutrino turned into a tau type neutrino. This is of course an important discovery in itself, but in truth it did not surprise anyone because the phenomenon of neutrino oscillations had been discovered earlier.
By the way, the study of neutrino particles is important in understanding nuclear processes. A neutrino detector allows, for example, to monitor the activity of an atomic reactor from a distance of hundreds of kilometers. In addition, they are used to study stellar activity, supernovae, and perhaps most importantly - they may help to better understand the Big Bang.
To by an anonymous user (unidentified)
In my response (No. 8) I was not referring to you, but to the names I mentioned: Dani, Yehuda and Rouch Rafaim.
Now you, in your response (No. 13) claim that one of these just now, you probably processed the concentration
And you revealed the multiple names you use. I expect you to be a little more careful in the future.
Responder 21 Don't you have any new Harry Potter to read?
The reminder reminds me of Hugin
Sub-Agony of CERN-at CERN:
They wondered and stared at the mysteries of the disappearing particle..
They dug a tunnel in tracing the paths of "Blam"
Play randomly and calculate the odds
Stir up a huge upheaval lest a huge hole be discovered..
Their plan was to pop
But one Saturday..they cooked a great cholent of Atum.
Finally, at the time of Uranus there was a seven-year mini cycle
Discovered in their calculations..the great "Tau". :)
to Beelzebub
Thank you from the bottom of my heart for the instruction regarding image enlargement.
Unfortunately I didn't notice this option before.
sympathetic:
The story with the sun is true (and is also mentioned in the links I provided), but the conclusion about neutrino variation is only certain if we assume that we know for sure what is happening inside the sun and on the way between it and us. This is a much less certain situation than the artificially created situation in the current experiment where we know with greater certainty what we are doing.
That is why it is written in the first link I provided in response 11 as follows:
In May 2010, it was reported that physicists from CERN and the Italian National Institute of Physics' Gran Sasso National Laboratory, had observed for the first time a transformation in neutrinos; evidence that they have mass.
I don't know what this research will yield, but I know how much the skeptics have done
In the USA they asked "what will the eccentric Robert Goddard's research do for us
On liquid-fueled missiles?” - and unlike the Nazis, they did not allocate money
public for these studies; It is possible that the Second Elam War was much shorter
And many American pilot lives would have been saved in it, if the Americans had invested then
what they could invest in this field of research.
Unfortunately for Londoners, who did believe in this area of research
As mentioned, there were the Nazis.
On the other hand, happily, the Nazis dismissed atomic research as "science."
Jewish", which has no value - and they didn't invest a lot of money in it, even though it is an original
The first and most significant heavy water in the world in those years passed into their hands
Already at the beginning of World War II.
I want to say that history proves that by simply raising the question "what will he give us
This research", many paid with their blood, therefore, it is worth learning from the painful and expensive experience
This - and not to turn this question into a way of thinking, because those who don't learn
From history he is condemned to pay heavy prices for the lessons he will receive from reality itself.
Well, another discovery! It reminds me of Darwin with his theory. It really matters to us that the origin of man in evolution is from the ape. And even more ridiculous was this Jew, well, what's his name? Yes, Albert, who theorized about how the universe was created and all sorts of other lines of formulas. Well, the overdraft really makes a difference to me!
The most ridiculous thing is that I heard that huge companies are working on developing anti-gravity engines. Well, another machine that will make fat people smile...
It is not clear to me why the above disclosure is historical, I assume that it is a matter of public relations that comes to justify the massive funding in the facility. The story of the neutrino oscillations is indeed amazing, but it was discovered earlier and was the basis of the explanation for the mystery of the lack of neutrinos from the sun. The story begins with the amazing experiment of Ray Davies and John Bacall who placed a huge chlorine tank that was buried in a mine one and a half kilometers underground. The tank contained 600 tons of cleaning fluid (rich in chlorine) and its function was to capture neutrinos from the sun by turning chlorine into radioactive argon. Finally, the number of nitrites that came from the sun and were measured in the KDA was smaller by approximately a factor of 3 than the one obtained in the calculation. Various accusations were made on the one hand about the experimentalists who do not know how to measure accurately and evaluate errors. After all, it is likely that in a giant chlorine tank there will be uncounted cases of neutrinos being hit. The chlorine atom turns into a radioactive argon when it is hit by a nitrite, and the argon atoms are to be found in the giant tank (single atoms!!!). On the other hand, accusations were leveled against the theorists who do not know how to properly calculate the number of nitrites created in the sun, then a detailed model based on many estimates of the sun is needed. What is the likelihood that such a model will be correct? In the end it turned out that both sides were right. It's just that some of the neutrinos emitted from the sun turned into another type of neutrinos (neutrino oscillations) and therefore were not detected. Neutrino oscillations were confirmed experimentally by comparing neutrino detection in two waves on both sides of the Earth. The detectors gave different readings because some of the rays that passed through the Earth became of a different type.
The Nobel Prize in Physics was awarded to Ray Davies for his neutrino experiment. The first experiment was conducted at the end of the sixties. The genius of the experiment was how to find in this huge container an atom or two of argon which is the result of the neutrino interaction with chlorine. And the organization must be found with such precision that the result can be compared with theoretical estimates! By the way, here in Israel at the Weizmann Institute is one of the world's greatest experts in neutrinos, Prof. Eli Waxman.
As far as I know, Thomson's quote is "let's make a toast for the useless electron" or in English: "lets make a toast for the useless electron"
A refreshing discovery.
I wonder what the theoretical and philosophical significance of the discovery is, and how long it will take until there is more than 98% certainty of discovery, hopefully within our lifetime.
Sorry, correction: I wrote that the Higgs lacks mass. This is of course not true, the Higgs boson is a very heavy particle.
Ben Ner
You misunderstood me, I'm really happy about the discovery.
In my opinion, this is another small step on the way that will unite the electro-weak force with the strong nuclear force.
Yossi, clicking on the two rectangles that appear next to the image's caption will enlarge it for you
http://en.wikipedia.org/wiki/Neutrino#Flavor_oscillations
http://en.wikipedia.org/wiki/Neutrino_oscillation
It is not clear
The tauoni neutrino has been known for a long time, so what was your discovery?
Maybe the discovery you are referring to is the transformation of neutrinos of a certain type into another type?
Why is the picture so small?
Many times a link to the original article is given and thus you can find an option to enlarge the image.
Here they tell about things in the picture (and the meanings) in a long and detailed description, but nothing can be seen. Too bad. This is probably a historical picture (especially if there are additional confirmations of what was discovered, but even if not).
Can I get a link to enlarge?
To the cynical and skeptical commenters (Danny, Yehuda and Rucha Ra'im)
A few months ago I heard the lecture of the physicist, Prof. Mark Karliner at Tel Aviv University,
In a lecture in memory of Prof. Aharon Katzir. The subject of the lecture was: the Large Hadron Collider at CERN,
Subatomic elementary particles, multidimensional world, etc.
Of course, already at the beginning of the lecture, the question of the relevance of these fields of tomorrow came up
to the life of human application and action and the viability of engaging in these fields.
Fr. Karliner brought in this context, a quote from the writings of J.J. Thomson, the discoverer of the electron.
In Thomson's time, the electron had not yet been named and was called the tiny particle smaller than the atom.
Even in Thomson's time, in the second half of the 19th century, there were many who attacked the research
The modern science of those times, from the same reasons that are heard today such as: lack of applicability,
Waste of money, etc. Prof. Karliner quoted the following from the letters of J.J. Thomson:
(Unfortunately, I do not have the exact quote and am bringing the things from memory)
"..the new particle we discovered is so small and fast in its movement, that there is no chance for a person
will ever be able to see it or make any practical use of it.
The discovery of this tiny particle is only of theoretical importance..."
I believe that G, G, Thomson also believed that in the future practical uses would be found for the new particle
that he discovered, but under the pressure of critical and hostile public opinion, he felt obliged to justify himself, dwarf and diminish
the public's expectations of the immediate benefit, to society and the economy, of the new scientific discovery.
There is no need to exaggerate the importance of the discovery of the electron to the discovery of the laws of electricity and magnetism and their contribution
The mighty for technology, society, well-being and cultural progress in our time.
Perhaps Dr. Gali Weinstein, as an expert in the field of the history of the sciences, could bring later,
the exact quotation of the things, as written by G, G, Thomson, and come for the thanks and the blessing.
Miu who became Tao????!!!
And to think that all these years I lived a lie...
that many physicists were right….
And that many physicists were wrong...
And most importantly, that our understanding took another small step forward...
What is the importance and meaning of the discovery?
Another step on the way to discovering particles with zero mass like the Higgs!
how fun.
I offer a group photo of one hundred and seventy scientists with 12 flags posing against the background of the tau particle
You can also add a picture of Mao who has already said everything
And in the middle of the 730 km road to erect a tombstone and write on it in capital letters:-
"Here Tao passed 1.2 seconds after Miu was"
Come on, let's go to sleep
night tao
Sabdarmish Yehuda
This is a huge waste of money simply for the sake of wasting it
If this is true, then this is the first significant discovery for the current millennium