Bottomonium particles don't go with the flow

Bottomonium particles don’t go with the flow
The ALICE experiment. Credit: CERN

A few millionths of a second after the Big Bang, the universe was so dense and hot that the quarks and gluons that make up protons, neutrons and other hadrons existed freely in what is known as the quark–gluon plasma. The ALICE experiment at the Large Hadron Collider (LHC) can recreate this plasma in high-energy collisions of beams of heavy ions of lead. However, ALICE, as well as any other collision experiments that can recreate the plasma, cannot observe this state of matter directly. The presence and properties of the plasma can only be deduced from the signatures it leaves on the particles that are produced in the collisions.

In a new article, presented at the ongoing European Physical Society conference on High-Energy Physics, the ALICE collaboration reports the first measurement of one such signature—the elliptic flow—for upsilon produced in lead–lead LHC collisions.

The upsilon is a bottomonium particle, consisting of a bottom (often also called beauty) quark and its antiquark. Bottomonia and their charm-quark counterparts, charmonium particles, are excellent probes of the quark–gluon . They are created in the initial stages of a heavy-ion collision and therefore experience the entire evolution of the plasma, from the moment it is produced to the moment it cools down and gives way to a state in which hadrons can form.

One indication that the –gluon plasma forms is the collective motion, or flow, of the produced particles. This flow is generated by the expansion of the hot plasma after the collision, and its magnitude depends on several factors, including: the particle type and mass; how central, or "head on," the collision is; and the momenta of the particles at right angles to the collision line. One type of flow, called elliptic flow, results from the initial elliptic shape of non-central collisions.

In their new study, the ALICE team determined the elliptic flow of the upsilons by observing the pairs of muons (heavier cousins of the electron) into which they transform, or "decay." They found that the magnitude of the upsilon elliptic flow for a range of momenta and centralities is small, making the upsilons the first hadrons that don't seem to exhibit a significant elliptic flow.

The results are consistent with the prediction that the upsilons are largely split up into their constituent quarks in the early stages of their interaction with the plasma, and they pave the way to higher-precision measurements using data from ALICE's upgraded detector, which will be able to record ten times more upsilons. Such data should also cast light on the curious case of the J/psi flow. This lighter charmonium particle has a larger flow and is believed to re-form after being split up by the plasma.


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More information: Measurement of Υ(1S) elliptic flow at forward rapidity in Pb-Pb collisions at √sNN=5.02 TeV. arxiv.org/abs/1907.03169
Provided by CERN
Citation: Bottomonium particles don't go with the flow (2019, July 17) retrieved 22 August 2019 from https://phys.org/news/2019-07-bottomonium-particles-dont.html
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Jul 17, 2019
If we believe that our World has started sometimes ago we are still in the position to decide which hypothesis, Lemaître's or Gamow's was closer to reality. There is an opinion that the problems in the standard cosmology could be solved by adjusting of details. Our suggestion is that we have to go back to the conceptions and use the observations accumulated since.
https://www.acade...osmology

Jul 17, 2019
Obviously whoever titled this doesn't understand physics. The point is the beauty quarks don't recombine. This is why they can see deeper-- both in space and time-- into the explosion of collision debris.

It's not "going against the flow."

Jul 18, 2019
Haha, what a load of bullshit.

Good luck finding any particle other than photons from now on.
They can try chanting "Magnetism is perpendicular to the current" and drawing a big Plus sign on Alice, maybe that will fix it!.

Jul 18, 2019
I keep reporting for spam; and the same author, without the slightest vestige of a shape-shifting name change, keeps spamming his own article hobby-horse with total impunity. It shouldn't even be a matter of reporting. The author should simply be permanently blocked.

Jul 18, 2019
Obviously whoever titled this doesn't understand physics. The point is the beauty quarks don't recombine. This is why they can see deeper-- both in space and time-- into the explosion of collision debris.

It's not "going against the flow."
I don't think the title is presenting a contra-theoretical anomaly, but just using a colorful discription of their behavior. In the article, she has: "The results are consistent with the prediction that the upsilons..."

Jul 18, 2019
@dan, on the spam thing, I reported it a few times and nothing was done so I assume they considered it harmless. I wouldn't advise you to continue reporting it. It just irritates the moderator(s). If they were going to do anything they'd have done it already.

On the article title, I read it as the bottoms retreating toward the collision. Someone's trying to make clickbait rather than making accurate titles. This has been an increasing trend. I don't like it. What's really going on is that they're able to trace the bottomonium back further, closer to the collision. This is not "going against the flow" and it biases the not-so-physics-sophisticated reader into thinking the former, rather than the latter. The article itself was written by someone at CERN, so the fault presumably lies there.

Jul 18, 2019
@Da Schneib.
Obviously whoever titled this doesn't understand physics. The point is the beauty quarks don't recombine. This is why they can see deeper-- both in space and time-- into the explosion of collision debris.

It's not "going against the flow."
Where did you get that "against the flow" impression, mate? The salient point is that the "Bottomonium" upsilon particles do not last long enough after their creation in the collision to be able to persist as Bottomonium particles for any significant length of time/path length along the asymmetric-collision-case Elliptical Flow streaming out of off-centre collisions. The term 'elliptical flow' was coined to reflect the off-centre-collision-contact-area 'shape' suggestive of an 'almond shape' (to visualise it, draw two overlapping, non-concentric circles and then note the shape of the area of overlap between the two off-centre circles). See? There is NO "against the flow" implied by the title/article, mate. :)

Jul 18, 2019
@RC, errr, from the title?

What's the matter with you, @RC?

Jul 18, 2019
Thread where @112LiarRC claims his "non math" approach is both abstract and non-abstract, and both is and is not math: https://phys.org/...ure.html
Thread where @112LiarRC lies about how long it takes a shockwave to move through a giant molecular cloud: https://phys.org/...cal.html
Thread where @112LiarRC lies fifteen times in ten posts and still can't stop, even when told he's being baited into lying: https://phys.org/...h_1.html
Thread where @112LiarRC lies that defining a black hole is "calling it black." https://phys.org/...ole.html
Thread where @112LiarRC lies about helium flash white dwarf detonations: https://phys.org/...arf.html

Jul 18, 2019
@Da Schneib.
Where did you get that "against the flow" impression, mate?

@RC, errr, from the title?
DS, can you please explain to the forum, in your own words, how you could possibly read "don't go with the flow" as saying "going against the flow", mate? Thanks. :)

Jul 18, 2019
Now you're parsing to try to "win."

Disgusting. Despicable. Narcissistic. Like Trump.

Like you always do. I'll leave it to observers to spot how @112LiarRC twisted my statement.

Jul 18, 2019
Thread where @112LiarRC lies about galactic dynamics following visible matter: https://phys.org/...rse.html
Thread where @112LiarRC lies about dark matter existing inside stars: https://phys.org/...ion.html
Thread where @112LiarRC lies about what Penrose and Steinhardt said about the Big Bang: https://phys.org/...ark.html
Thread where @112LiarRC lies about fractals even though it claims to reject math: https://phys.org/...rse.html
Thread where @112LiarRC lies about real infinity existing in physical reality again: https://phys.org/...rse.html

Jul 18, 2019
@Da Schneib.
Where did you get that "against the flow" impression, mate?

@RC, errr, from the title?
DS, can you please explain to the forum, in your own words, how you could possibly read "don't go with the flow" as saying "going against the flow", mate? Thanks. :)
Now you're parsing to try to "win." I'm not the one doing the "parsing", mate. It was you doing the "unwarranted assuming" when you (mis)reading that title. Consider: If a particle is absent from a flow, can it be assumed that it is somehow 'still in existence' and "going against the flow"...or is it that there is no particle there at all? That was the point of the title in the context of the article; ie, that the Bottomonium upsilon particle decays too quickly to take part in the elliptic flow from the off-centre collision cases.

And it isn't a case of "trying to win"; it's trying to fathom how you got "going against the flow" from the title "don't go with the flow" based on the context. Ok? :)

Jul 18, 2019
What a transparent, infantile, narcissistic troll you are.

Jul 18, 2019
@Da Schneib.
Where did you get that "against the flow" impression, mate?
@RC, errr, from the title?
DS, can you please explain to the forum, in your own words, how you could possibly read "don't go with the flow" as saying "going against the flow", mate? Thanks. :)
Now you're parsing to try to "win."
I'm not the one doing the "parsing", mate. It was you doing the "unwarranted assuming" when you (mis)read that title. Consider: If a particle is absent from a flow, why did you assumed it is somehow 'still in existence' and "going against the flow"..if there is no particle there at all? That was the point of the title in the context of the article; ie, that the Bottomonium upsilon particle decays too quickly to take part in the elliptic flow from the off-centre collision cases.

ps: it isn't a case of "trying to win"; it's trying to fathom how you got "going against the flow" from the title "don't go with the flow" based on the context. Ok? :)

Jul 18, 2019
Thread where @112LiarRC tries to support EUdiocy (despite claiming not to): https://phys.org/...ion.html
Thread where @112LiarRC makes up stories about another poster: https://phys.org/...ars.html
Thread where @112LiarRC insults a user by lying about what that user said: https://phys.org/...ter.html
Thread where @112LiarRC lies about GR "predicting" singularities: https://phys.org/...s_1.html
Thread where @112LiarRC lies about BICEP2 and gets pwnt: https://phys.org/...urt.html
Note this last thread recapitulates an ongoing claim by @112LiarRC that "four defects" were found in the BICEP2 paper on inflation and @112LiarRC has never said what three of them are.

Jul 18, 2019
@Da Schneib.

Stop wasting precious time and mental resources on your misreading/misunderstandings spam.

Expend them instead on the important things...like reading comprehension in context, for example.

Again, DS:

It was YOU doing the "unwarranted assuming" when you (mis)read that title.

CONSIDER: If a particle is absent from a flow, why did you assume it is somehow 'still in existence' and "going against the flow"..if there is no particle there at all?

See? THAT was the point of the title in the context of the article; ie, that the Bottomonium upsilon particle decays too quickly to take part in the elliptic flow from the off-centre collision cases.

Just admit you presumed/misread what the title implied in context, and move on without all the drama and spam, mate. Good luck. :)

Jul 18, 2019
If a particle is absent from a flow
What particle is absent from what flow? This article (and the paper underlying it) do not say that.

You're lying again, @113LiarRC.

Jul 18, 2019
@Da Schneib.
If a particle is absent from a flow
What particle is absent from what flow? This article (and the paper underlying it) do not say that.

You're lying again, @113LiarRC.
Didn't you read that the Bottomonium particles are destroyed during the earliest stages of the collision aftermath; and that because, unlike some other particles, they are not 'regenerated', and so do not exist any longer; hence why they cannot "go with the flow" [ie, the Elliptical flows) observed to be lacking in Bottomonium upsilon particles? :)

Jul 18, 2019
No. I read the bottom/beauty quarks come out and then decay.

On Earth.

And now they have figured out how they do that.

On Earth.

Jul 18, 2019
@Da Schneib.
Didn't you read that the Bottomonium particles are destroyed during the earliest stages of the collision aftermath; and that because, unlike some other particles, they are not 'regenerated', and so do not exist any longer; hence why they cannot "go with the flow" [ie, the Elliptical flows) observed to be lacking in Bottomonium upsilon particles? :)
No. I read the bottom/beauty quarks come out and then decay.
Here, maybe these snippets will help:
The UPSILON is a BOTTOMONIUM particle, consisting of a BOTTOM (often also called BEAUTY) QUARK and ITS ANTIQUARK. ... They found that the magnitude of the upsilon elliptic flow for a range of momenta and collision centralities is small, making the upsilons the first hadrons that DON'T SEEM TO EXHIBIT A SIGNIFICANT ELLIPTICAL FLOW. The results are consistent with the prediction that the upsilons are LARGELY SPLIT into their constituent quarks IN THE EARLY STAGES of their interaction with the plasma,..
Ok? :)

Jul 18, 2019
So, how exactly is that different from what I said? And what does it have to do with upsilons and their constituent bottom/beauty quarks not "going with the flow" since they seem to come out just like everything else?

Stop pretending to understand things about particle physics you obviously don't understand.

This is more of your standard bullshit.

Knock it off, troll.

Jul 18, 2019
@Da Schneib.
So, how exactly is that different from what I said? And what does it have to do with upsilons and their constituent bottom/beauty quarks not "going with the flow" since they seem to come out just like everything else? Stop pretending to understand things about particle physics you obviously don't understand. This is more of your standard bullshit. Knock it off, troll.
It confirms what I said about them being destroyed before they can proceed to join the Elliptical flows to any significant degree/length. That was the whole point of the article/paper. It compares that early stage destruction (and consequent absence in further elliptical flows) to the 'regeneration' of those other particles that CAN therefore join, and so can be detected in, those Elliptical flows to significant degree/length. You are confusing things for everyone again, mate. Take more time to read/understand things properly in context before jumping to mistaken conclusions and insults. Ok? :)

Jul 18, 2019
The bottom/beauty quarks are not "destroyed." You're lying again, @116LiarRC.

Jul 18, 2019
@Da Schneib.
The bottom/beauty quarks are not "destroyed." You're lying again, @116LiarRC.
No! I NEVER said that at all.

I only said it's the BOTTOMONIUM PARTICLE, ie, the COMBINATION of the Bottom (or Beauty) quark/antiquark that is destroyed (ie, SPLIT into the constituent quark and antiquark) early on in the collision aftermath. :)

As stated in the article clear as day. I even quoted the relevant snippets for you, DS!

DS, please take more time and make more genuine effort to try to read/understand properly in context before jumping to your own misconstrued 'knee-jerk takes' on what is written clear as day.

Please. Thanks. No hard feelings. :)

Jul 19, 2019
The bottomonium particles aren't destroyed either. So it doesn't really matter what you claimed was being destroyed. The word "destroyed" doesn't appear anywhere in the article.

You have not the slightest idea what is happening there, and the more you talk the clearer it is.

Jul 19, 2019
@Da Schneib.
The bottomonium particles aren't destroyed either. So it doesn't really matter what you claimed was being destroyed. The word "destroyed" doesn't appear anywhere in the article. You have not the slightest idea what is happening there, and the more you talk the clearer it is.
DS, please explain to the forum what exactly is it that you don't understand about...
The Bottomonium Particle (composed of a Bottom, or Beauty, Quark and its Antiquark) is SPLIT (EARLY ON in the collision aftermath) into its constituent Bottom (or Beauty) Quark and Antiquark and hence cannot be present to any significant degree/length in the Elliptical Flows issuing from the off-centre collisions.
...and especially clarify why it is that you seem to think that the Bottomonium is NOT destroyed/disintegrated into its constituent quarks despite it being SPLIT as described in the article/paper. Take your time. Thanks. :)

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