New CERN results show novel phenomena in proton collisions

April 25, 2017 by Harriet Kim Jarlett, CERN
As the number of particles produced in proton collisions (the blue lines) increase, the more of these so-called strange hadrons are measured (as shown by the orange to red squares in the graph). Credit: ALICE/CERN

In a paper published today in Nature Physics , the ALICE collaboration reports that proton collisions sometimes present similar patterns to those observed in the collisions of heavy nuclei. This behaviour was spotted through observation of so-called strange hadrons in certain proton collisions in which a large number of particles are created. Strange hadrons are well-known particles with names such as Kaon, Lambda, Xi and Omega, all containing at least one so-called strange quark. The observed 'enhanced production of strange particles' is a familiar feature of quark-gluon plasma, a very hot and dense state of matter that existed just a few millionths of a second after the Big Bang, and is commonly created in collisions of heavy nuclei. But it is the first time ever that such a phenomenon is unambiguously observed in the rare proton collisions in which many particles are created. This result is likely to challenge existing theoretical models that do not predict an increase of strange particles in these events.

"We are very excited about this discovery," said Federico Antinori, Spokesperson of the ALICE collaboration. "We are again learning a lot about this primordial state of matter. Being able to isolate the -like phenomena in a smaller and simpler system, such as the collision between two protons, opens up an entirely new dimension for the study of the properties of the fundamental state that our universe emerged from."

The study of the quark-gluon plasma provides a way to investigate the properties of strong interaction, one of the four known fundamental forces, while enhanced strangeness production is a manifestation of this state of matter. The quark-gluon plasma is produced at sufficiently high temperature and energy density, when ordinary matter undergoes a transition to a phase in which quarks and gluons become 'free' and are thus no longer confined within hadrons. These conditions can be obtained at the Large Hadron Collider by colliding heavy nuclei at high energy. Strange quarks are heavier than the quarks composing normal matter, and typically harder to produce. But this changes in presence of the high energy density of the quark-gluon plasma, which rebalances the creation of strange quarks relative to non-strange ones. This phenomenon may now have been observed within proton collisions as well.

In particular, the new results show that the production rate of these strange hadrons increases with the 'multiplicity' – the number of particles produced in a given collision – faster than that of other particles generated in the same collision. While the structure of the proton does not include strange quarks, data also show that the higher the number of strange quarks contained in the induced hadron, the stronger is the increase of its production rate. No dependence on the collision energy or the mass of the generated particles is observed, demonstrating that the observed phenomenon is related to the strange quark content of the particles produced. Strangeness production is in practice determined by counting the number of strange particles produced in a given collision, and calculating the ratio of strange to non-strange particles.

Enhanced strangeness production had been suggested as a possible consequence of quark-gluon plasma formation since the early eighties, and discovered in collisions of nuclei in the nineties by experiments at CERN's Super Proton Synchrotron. Another possible consequence of the quark gluon plasma formation is a spatial correlation of the final state particles, causing a distinct preferential alignment with the shape of a ridge. Following its detection in heavy-nuclei collisions, the ridge has also been seen in high-multiplicity proton collisions at the Large Hadron Collider, giving the first indication that proton collisions could present heavy-nuclei-like properties. Studying these processes more precisely will be key to better understand the microscopic mechanisms of the -gluon and the collective behaviour of in small systems.

The ALICE experiment has been designed to study collisions of heavy nuclei. It also studies proton-, which primarily provide reference data for the collisions. The reported measurements have been performed with 7 TeV data from LHC run 1.

Explore further: 'Littlest' quark-gluon plasma revealed by physicists using Large Hadron Collider

More information: J. Adam et al. Enhanced production of multi-strange hadrons in high-multiplicity proton–proton collisions, Nature Physics (2017). DOI: 10.1038/nphys4111

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BEGINNING
1.3 / 5 (16) Apr 25, 2017
The super-intellligent Designer is proving to be beyond reach...... things are always more complex than that what the scientific community as a whole is able to imagine...
axemaster
4.7 / 5 (14) Apr 25, 2017
Clearly you're only at the BEGINNING of your education...
antialias_physorg
4.5 / 5 (15) Apr 25, 2017
Clearly you're only at the BEGINNING of your education...

Not even that. He gave up before he even started and plumped for some con-man's 'explanation' (i.e. "God did it. Don't question me. Gimme money.")
Gigel
3.7 / 5 (3) Apr 25, 2017
Things are found to be more complex because that is the preferential direction of knowledge and thus research: towards the new and more complex.

What is the source of that complexity... is open for debate. Natural laws found by research almost invariably end up as being quite simple and concise. Yet they appear to be generating an awful lot of complexity, including life itself. Why is that so... it is hard to tell.

Even assuming that it is normal for simple laws to generate a lot of complexity is not going to solve that mystery. One could end up wondering on the purpose of those laws and of their consequences. The purpose is a type of cause according to Aristotle.

At the edge of knowledge anything works, everything is possible.
Hyperfuzzy
Apr 25, 2017
This comment has been removed by a moderator.
gculpex
5 / 5 (1) Apr 25, 2017
I think it's a belief that magic exist!

It's magic until science provides a consistent theory.
Kron
3 / 5 (1) Apr 25, 2017
The source of complexity, Gigel, I think would be the spontaneous symmetry breaking. Gravity breaking from the 4 known forces following the Planck Epoch (time of quantum gravity), then the strong nuclear force breaking from the electronuclear force following the Grand Unification Epoch (time when strong-nuclear-force weak-nuclear-force and electromagnetism were one), then weak force breaking from electroweak force following the electroweak epoch.

I guess the answer to complexity would be: time; entropy; thermodynamics... You pick.
Hyperfuzzy
1 / 5 (3) Apr 25, 2017
I think it's a belief that magic exist!

It's magic until science provides a consistent theory.

Try Maxwell without GR or SM of which neither are coherent. It will simplify your "search"; however, the truth is right before your eyes. Empirical truth, not assumed truths, truth upon which everything is based upon, our measurements, solid physics, Maxwell! Charge has no mass and is not a particle, it is transparent, the entire field is the charge. It exist from it's center to infinity. Empirical! We only "see" the wrinkles in the field. The massive summation of the static fields yield gravity, just don't forget the environment. The manner conglomerates are formed would be fusion, asteroids, planets, solar systems, galaxies, super galaxies, ...
Dingbone
Apr 25, 2017
This comment has been removed by a moderator.
EyeNStein
5 / 5 (2) Apr 26, 2017
The phase change from normal hadronic matter to QGP is at 175MeV. (Far lower than the 14TeV total energy the LHC can provide.)

The reason the emergence of the QGP phase is unexpected is that 7TeV is spread out randomly across numerous gluons, virtual gluons, and quarks in each hadron, and injected into the 14TeV fireball they create.(Which is why it took a 7TeV hadron experiment to make the 125MeV Higgs boson in sufficient quantities to measure.)

This result implies that the 14Tev energy is shared more evenly, than they thought, between a fewer number of particles in this new quark plasma soup: To get enough collective QGP phase particles for their statistics to indicate their presence.

Perhaps energy is shared more evenly because many QM entangled particles are created?
An interesting result for strong force thermodynamics.

(And no magic involved)
Hyperfuzzy
1 / 5 (2) Apr 26, 2017
The phase change from normal hadronic matter to QGP is at 175MeV. (Far lower than the 14TeV total energy the LHC can provide.)

The reason the emergence of the QGP phase is unexpected is that 7TeV is spread out randomly across numerous gluons, virtual gluons, and quarks in each hadron, and injected into the 14TeV fireball they create.(Which is why it took a 7TeV hadron experiment to make the 125MeV Higgs boson in sufficient quantities to measure.)

This result implies that the 14Tev energy is shared more evenly, than they thought, between a fewer number of particles in this new quark plasma soup: To get enough collective QGP phase particles for their statistics to indicate their presence.

Perhaps energy is shared more evenly because many QM entangled particles are created?
An interesting result for strong force thermodynamics.

(And no magic involved)

Virtual nonsense, gluons?
Hyperfuzzy
1 / 5 (3) Apr 30, 2017
I like what we are doing at CERN. It has nothing to do with new particles sense subatomic particle are not real. There only exist charge as diametrical spherical fields. I challenge CERN to produce just one spherical electric field without charge. No that's not fair, just produce an electric field without charge. OK, that's not even fair, how about demonstrating theoretically how we are created from nothing without magic.

Beautiful thing space, filled with nothing but these diametrical spherical fields we call charge. The E field, is your mystery, can't measure anything without it, can't have matter without it, can't exist without it. Hmmm, guess these exist. Now why would we require anything else? Juz say'n

I conjecture empty space is only conceptual. BB, GR, SM,ST, all pretty good guesses but wrong. What kind of paper is required to define a garbage truck?
Da Schneib
3 / 5 (2) Apr 30, 2017
Fascinating that it should be linked only to the number of particles created, and not to energy or mass or another conserved quantity. We may be looking at a new principle of quantum mechanics here. I'd particularly like to explicitly know the significance level of this; since there's no hedging, the signs say >5σ, but it would be good to see that in print.

UPDATE: The article is open access! Reading...
Da Schneib
3 / 5 (2) Apr 30, 2017
This appears to be high-quality direct detection of the strangeness enhancement with multiplicity increase. It's inappropriate to talk about the significance of results in this regime; these are pretty much direct experimental results. What is, is.

Very interesting indeed! There is an unknown effect here. This will be interesting to watch. Perhaps Jester will get unstuck and make a blog post soon.
Dingbone
Apr 30, 2017
This comment has been removed by a moderator.
Hyperfuzzy
1 / 5 (2) Apr 30, 2017
... whole atom nuclei.

My hobby, theoretical physics, qualifications, MSEE, proof requires more than 6 Sigma, it requires an unquestionable axiom. I question everything and support my reasons with logic and instrumentation. The axiomatic structure of the standard model has no electrons in the nucleus, I state that a neutron is a containment of an electron and a proton. Therefore the SM is based upon a false principle. The neutron is not a single particle. Hence measurements of field events are simply field events with an erroneous analysis of results of proton collisions. I mean this in a happy way. I know what awaits us with reason! juz say'n
Hyperfuzzy
1 / 5 (2) Apr 30, 2017
You may bash protons together as often as you wish with higher and higher power. Think, what happens in a proton cloud at high velocity. All the forces at play, if a single polarity, are repulsive. What your detectors actually record is not what you say is happening.

You will get the same results with electrons at the same counts and energy, juz say'n

So put that in your pipe and smoke it. This will disprove the standard model. When you finish, I would like a Nobel, I'm poor. Note: My paper is an anti-paper of the 20th century, no one really needs to read this, in fact do som'n som'n to clear the record for the 20th century will have us all looking like idiots. Don't forget to dis Einstein as what can happen when you don't pay attention in class..
nikola_milovic_378
May 02, 2017
This comment has been removed by a moderator.
nikola_milovic_378
May 02, 2017
This comment has been removed by a moderator.
Hyperfuzzy
1 / 5 (1) May 02, 2017
...
When he got home, the woman becomes that from which she was before lipstick.
Tell those workers in Cern, will never get a new natural particle. All this will be "stillborn abortion".

Particles are the center of the field. One need not wonder how they are formed, we exist because "Empty Space" does not exist and never has. Each charge occupies all of space, from its center to infinity. Where at infinity the field is zero. By the way there are an infinite number of these diametrical spherical fields. The particles are the fields. Anyway, keep trying, make up stuff or apply logic. First, what is your axiomatic structure? You can't define a theory without at least 1 axiom. Looking for something to fit your thinking is perfectly OK. Just don't give NOBELs for poor theory and don't waste your time trying to create something from nothing. It's OK to be wrong, just don't continue with nonsense.
gculpex
not rated yet May 19, 2017
it seems the collisions are pointing to a new branch of theory, a reverse jet from the heavier quarks.
Hyperfuzzy
not rated yet May 20, 2017
it seems the collisions are pointing to a new branch of theory, a reverse jet from the heavier quarks.

Theory, with a mystery at the end!
nikola_milovic_378
May 20, 2017
This comment has been removed by a moderator.
nikola_milovic_378
May 20, 2017
This comment has been removed by a moderator.
Hyperfuzzy
1 / 5 (1) May 20, 2017
What is an axiom? This is unprovable truth. My theory does not start from nothing. Everything in the universe is created from something, but if we come to the end of the questions, what is what caused, we must accept the fact that there is someone or something that we can not draw conclusions because we are formed under the influence of that which we can not make marks. To change the direction of advancement of science in the scope of discussion, the axioms are: ether, the substance from which it is formed and matter and all energy, too, is axiomatic and infinite universe, but the Creator of everything in the universe. This is what I wrote is just a short excerpt from a comprehensive thoughts about the origin of the material-energetic entities of the universe (MEEU) under the influence of the spiritual entity of the universe and his power of creation, and that is the absolute awareness of the universe (ACU).

No, an axiom is an accepted Truth. With a Truth we define Theory.
Hyperfuzzy
1 / 5 (1) May 20, 2017
With Theory reflecting Truth, simply because it is too small to notice or big to comprehend; does not infer something unbelievable. If you completely understand the fundamentals. These are quite simple, diametrical Spherical Fields, the Field Intensity inversely proportional to the surface of a sphere at the point in question relative to its center. The structure is unaffected by any other field, only the center dances, and the ripples created begin to shimmer. Let there be light!
nikola_milovic_378
May 21, 2017
This comment has been removed by a moderator.
Hyperfuzzy
1 / 5 (1) May 22, 2017
Accepted truth can be irrational and stupid conclusion, as science is accepted that appeared the Big Bang created from nothing.
Unprovable axiom is true, but accepted our consciousness and not a mathematical or fictitious models.
What you're talking about the filles is a philosophy from which they can make a lot of combinations of field types and their properties. In nature, everything is much simpler than what science invents only need to understand the true causes of the phenomenon.

yeah, everything else has this "PopUp" impossibility; so, what, say "ahhhh...

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