First open-access data from large collider confirm subatomic particle patterns

September 30, 2017 by Jennifer Chu
The Compact Muon Solenoid is a general-purpose detector at the Large Hadron Collider. Credit: CERN

In November of 2014, in a first, unexpected move for the field of particle physics, the Compact Muon Solenoid (CMS) experiment—one of the main detectors in the world's largest particle accelerator, the Large Hadron Collider—released to the public an immense amount of data, through a website called the CERN Open Data Portal.

The data, recorded and processed throughout the year 2010, amounted to about 29 terabytes of information, yielded from 300 million individual collisions of high-energy protons within the CMS detector. The sharing of these data marked the first time any major particle collider experiment had released such an information cache to the general public.

A new study by Jesse Thaler, an associate professor of physics at MIT and a long-time advocate for open access in , and his colleagues now demonstrates the scientific value of this move. In a paper published today in Physical Review Letters, the researchers used the CMS data to reveal, for the first time, a universal feature within jets of subatomic particles, which are produced when high-energy protons collide. Their effort represents the first independent, published analysis of the CMS .

"In our field of particle physics, there isn't the tradition of making data public," says Thaler. "To actually get data publicly with no other restrictions—that's unprecedented."

Part of the reason groups at the Large Hadron Collider and other particle accelerators have kept proprietary hold over their data is the concern that such data could be misinterpreted by people who may not have a complete understanding of the physical detectors and how their various complex properties may influence the data produced.

"The worry was, if you made the data public, then you would have people claiming evidence for new physics when actually it was just a glitch in how the detector was operating," Thaler says. "I think it was believed that no one could come from the outside and do those corrections properly, and that some rogue analyst could claim existence of something that wasn't really there."

"This is a resource that we now have, which is new in our field," Thaler adds. "I think there was a reluctance to try to dig into it, because it was hard. But our work here shows that we can understand in general how to use this open data, that it has scientific value, and that this can be a stepping stone to future analysis of more exotic possibilities."

Thaler's co-authors are Andrew Larkoski of Reed College, Simone Marzani of the State University of New York at Buffalo, and Aashish Tripathee and Wei Xue of MIT's Center for Theoretical Physics and Laboratory for Nuclear Science.

Seeing fractals in jets

When the CMS collaboration publicly released its data in 2014, Thaler sought to apply new theoretical ideas to analyze the information. His goal was to use novel methods to study jets produced from the high-energy collision of protons.

Protons are essentially accumulations of even smaller subatomic particles called quarks and gluons, which are bound together by interactions known in physics parlance as the strong force. One feature of the strong force that has been known to physicists since the 1970s describes the way in which quarks and gluons repeatedly split and divide in the aftermath of a high-energy collision.

This feature can be used to predict the energy imparted to each particle as it cleaves from a mother quark or gluon. In particular, physicists can use an , known as an evolution equation or splitting function, to predict the pattern of particles that spray out from an initial collision, and therefore the overall structure of the jet produced.

"It's this fractal-like process that describes how jets are formed," Thaler says. "But when you look at a jet in reality, it's really messy. How do you go from this messy, chaotic jet you're seeing to the fundamental governing rule or equation that generated that jet? It's a universal feature, and yet it has never directly been seen in the jet that's measured."

Collider legacy

In 2014, the CMS released a preprocessed form of the detector's 2010 raw data that contained an exhaustive listing of "particle flow candidates," or the types of that are most likely to have been released, given the energies measured in the detector after a collision.

The following year, Thaler published a theoretical paper with Larkoski and Marzani, proposing a strategy to more fully understand a complicated jet in a way that revealed the fundamental evolution equation governing its structure.

"This idea had not existed before," Thaler says. "That you could distill the messiness of the jet into a pattern, and that pattern would match beautifully onto that equation—this is what we found when we applied this method to the CMS data."

To apply his theoretical idea, Thaler examined 750,000 individual jets that were produced from proton collisions within the CMS open data. He looked to see whether the pattern of particles in those jets matched with what the evolution equation predicted, given the energies released from their respective collisions.

Taking each collision one by one, his team looked at the most prominent jet produced and used previously developed algorithms to trace back and disentangle the energies emitted as particles cleaved again and again. The primary analysis work was carried out by Tripathee, as part of his MIT bachelor's thesis, and by Xue.

"We wanted to see how this jet came from smaller pieces," Thaler says. "The equation is telling you how energy is shared when things split, and we found when you look at a jet and measure how much energy is shared when they split, they're the same thing."

The team was able to reveal the splitting function, or evolution equation, by combining information from all 750,000 jets they studied, showing that the equation—a fundamental feature of the strong force—can indeed predict the overall structure of a jet and the energies of produced from the collision of two protons.

While this may not generally be a surprise to most physicists, the study represents the first time this equation has been seen so clearly in experimental data.

"No one doubts this equation, but we were able to expose it in a new way," Thaler says. "This is a clean verification that things behave the way you'd expect. And it gives us confidence that we can use this kind of open data for future analyses."

Thaler hopes his and others' analysis of the CMS open data will spur other large particle physics experiments to release similar information, in part to preserve their legacies.

"Colliders are big endeavors," Thaler says. "These are unique datasets, and we need to make sure there's a mechanism to archive that information in order to potentially make discoveries down the line using old data, because our theoretical understanding changes over time. Public access is a stepping stone to making sure this data is available for future use."

Explore further: New particle flow algorithm improves ATLAS experiment precision

More information: Andrew Larkoski et al. Exposing the QCD Splitting Function with CMS Open Data, Physical Review Letters (2017). DOI: 10.1103/PhysRevLett.119.132003

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jloohunret
3 / 5 (6) Sep 30, 2017
Any use or application of particle accelerator experiment public data, fractal geometry or math derivate off fractal geometry could be useful later in the future. Possible fractal art or fractal pattern trove for password generation to anything else might result from this.
antialias_physorg
3.5 / 5 (8) Sep 30, 2017
You seem to love the word 'fractal', but you don't seem to understand what it means. Please look it up before posting again. It will save you no end of embarassment in the future.

Benni
1.5 / 5 (10) Sep 30, 2017
You seem to love the word 'fractal', but you don't seem to understand what it means. Please look it up before posting again. It will save you no end of embarassment in the future.


Mr Biologist, you should just stop posting, period.
Da Schneib
4.4 / 5 (7) Sep 30, 2017
@Lenni, you're the one who lies. You're the one who should just stop posting lies.

@anti makes a valid point, which is that people who don't understand fractional dimensions shouldn't post about them. Since you don't understand them either you identify yourself as a troll and an idiot. Not to mention a liar who claims to be able to solve PDEs and can't.
RealityCheck
1.6 / 5 (7) Sep 30, 2017
@antialias and @Da Schneib.

When will you learn NOT to denigrate posters for making perfectly valid observations/musings according to their own level of scientific/logic education/experience? Not all posters here have to be YOU. Nor must they agree only with YOUR perspectives/beliefs. So please allow others to express their opinions/musings without trying to shut them down by denigrating their efforts at communicating their perspectives/ideas. OK?

Now please NOTE:

FRACTAL is to do with NON-LINEAR PROCESS involving FEEDBACK dynamics/evolutions that produce the patterns/structures which can be mathematically/geometrically represented/described via fractal equations containing the applicable terms and feedback variables that NATURE is inherently producing as it continues to 'process' through all possible configurations and evolutionary trajectories.

Your simplistic/maths views are NOT any better than the views of those above whom you denigrate without just cause. LEARN. :)
Da Schneib
5 / 5 (4) Sep 30, 2017
@RC, all you do is lie anyway, so I see no point in responding other than to point out you lie every time you post.

Lying simply isn't going to work when your lies can be, and have been, posted over and over and over and over and over and over and over and over and over again.
Da Schneib
5 / 5 (6) Sep 30, 2017
Thread where @RC lies about current research into cosmic voids and gets caught: https://phys.org/...ies.html
Thread where @RC makes conflicting claims within ten posts and gets caught: https://phys.org/...ome.html
Thread where @RC claims there is "REAL/PHYSICAL UNIVERSAL 'infinity'" and gets caught: https://phys.org/...rgy.html
Thread where @RC claims Rubin said galaxies will implode with out DM and confuses Zwicky with Rubin:
https://phys.org/...zzy.html
Thread where @RC claims his "non math" approach is both abstract and non-abstract, and both is and is not math: https://phys.org/...ure.html

There are so many lies they won't even fit in one post. More coming in 3 minutes.
RealityCheck
1 / 5 (7) Sep 30, 2017
@Da Schneib.
@RC, all you do is lie anyway, so I see no point in responding other than to point out you lie every time you post. Lying simply isn't going to work when your lies can be, and have been, posted over and over and over and over and over and over and over and over and over again.
You haven't a clue, yet you ignore and remain clueless rather than LEARNING. Your ignore and insult/spam 'tactic' is NOT 'science', DS; it is ELABORATE DENIAL and STUPIDITY born of EGO and MALICE; things which you again unambiguously demonstrate by that post evading the point that you have no better understanding of fractal than those whom you insult. Learn, DS. Learn.
Da Schneib
5 / 5 (5) Sep 30, 2017
Thread where @RC lies about how long it takes a shockwave to move through a giant molecular cloud: https://phys.org/...cal.html

I mean seriously, why would anyone believe anything @RC says when he lies and lies and lies and lies and lies and lies and lies and lies and gets caught every time? This individual lies at the drop of a hat and tries like a three year old child to lie about that too, after being caught like a child with cookie crumbs on mouth and shirt and the broken container on the floor in front of it. It's a shame the moderators here permit this, but no one can possibly believe it.

Go lie down someplace else, @RC, everyone here but other #physicscranks sees through you.
RealityCheck
1 / 5 (6) Sep 30, 2017
@Da Schneib.
Thread where @RC lies about how long it takes a shockwave to move through a giant molecular cloud: https://phys.org/...cal.html

I mean seriously, why would anyone believe anything @RC says when he lies and lies and lies and lies and lies and lies and lies and lies and gets caught every time? This individual lies at the drop of a hat and tries like a three year old child to lie about that too, after being caught like a child with cookie crumbs on mouth and shirt and the broken container on the floor in front of it. It's a shame the moderators here permit this, but no one can possibly believe it.
The forum notes you repeatedly 'project' your own faults onto me, DS. It won't work anymore; your record of errors and stupidity resisting learning is all too evident. You were wrong in all those cases, and I correct all along; yet you try to twist it round in order to protect your oversized but all too fragile ego. LEARN!
Da Schneib
5 / 5 (4) Sep 30, 2017
Meanwhile, on Earth, open access data has been used to show that physics math is correct, and now the #physicsdeniers are trying to deny not theory but data.

If you have some sort of argument to make against data, and in favor of unicorns, go for it, but it sounds like the lies #physicsdeniers make up all the time so be prepared for extreme skepticism.

@RC, your lies are not faults of the forum or other posters; you lied, you got caught, you are the responsible party, and you are a lying #physicscrank troll. There is nothing more that needs to be said about you or anything you post.
RealityCheck
1 / 5 (7) Sep 30, 2017
@Da Schneib.
Meanwhile, on Earth, open access data has been used to show that physics math is correct, and now the #physicsdeniers are trying to deny not theory but data.

If you have some sort of argument to make against data, and in favor of unicorns, go for it, but it sounds like the lies #physicsdeniers make up all the time so be prepared for extreme skepticism.
Seriously, DS, what planet are YOU on? No-one here has done anything of the kind you just claimed. Why LIE like that, DS; is that the only way you can ''win' a discussion on your 'planet'?

The issue is YOU and antialias starting in and attacking and denigrating perfectly valid and polite comments from others on the fractal aspect of the data/science reported on. Period.

That you NOW try to pretend you are 'defending' that data/science makes you LAME and DISHONEST as well as in denial of your own FAULTS. LEARN, DS!
Da Schneib
5 / 5 (5) Sep 30, 2017
Apparently you have the fallacious impression that I am arguing with you, @RC. I am not. I am merely pointing out that every time you post you lie. There is no point in arguing with a liar since they'll just tell another lie.

Go away boy who cried wolf.
RealityCheck
1 / 5 (6) Sep 30, 2017
@Da Schneib.
Apparently you have the fallacious impression that I am arguing with you, @RC. I am not. I am merely pointing out that every time you post you lie. There is no point in arguing with a liar since they'll just tell another lie. Go away boy who cried wolf.
You are TROLLING in IGNORANCE and MALICE due to your own ego and denial of your own lies and flaws, DS. Your spate of insensible posts claiming I lie etc, while it is demonstrable to everyone that you are just 'going through the motions' of denial and ignorance and ego-tripping IN LIEU of honest engagement, tells readers everything they need to know about the 'credibility' of your 'claims' above, DS.

Why post here if you are IGNORANT while pretending to 'know' anything and attacking others who know more than you, DS? Are you a masochist as well as ego-tripping ignoramus, DS?

Never mind; just shut up and read and learn instead of opening your big mouth and insulting people who know more than you. Learn, DS.
Benni
1.6 / 5 (7) Sep 30, 2017
Meanwhile, on Earth, open access data has been used to show that physics math is correct, and now the #physicsdeniers are trying to deny not theory but data.


Old dude, you mean like the concept of CONSERVATION OF GRAVITY that you made up over on the LIGO article? Maybe you have some "physics math" & "data" for that you could put up? By the way, who gets the credit?
Da Schneib
5 / 5 (4) Sep 30, 2017
@Lenni and @RC are against public release of data sets by real scientists. It makes it easier to tell when they're lying.
Benni
1.5 / 5 (8) Sep 30, 2017
@Lenni and @RC are against public release of data sets by real scientists. It makes it easier to tell when they're lying.


You mean like the concept of CONSERVATION OF GRAVITY that you made up over on the LIGO article? Maybe you have some "physics math" & "data" for that you could put up? By the way, who gets the credit?

Schneibo, Old Dude.......Why is that all you do is go on name calling rants when somebody holds you to account for all YOUR screwed up claims about real physics math & data? For example:

and that entropy is consumed by BHs


The entropy cannot be retrieved


since matter has been converted into GW energy


You imagine that because YOU made up this pile of slop & swill that it is valid science? Such a high opinion of yourself is precisely why you don't know up from down.
Da Schneib
3.7 / 5 (6) Sep 30, 2017
If you're not against open access, then why are you posting on this thread, @Lenni?
Benni
1.8 / 5 (10) Sep 30, 2017
If you're not against open access, then why are you posting on this thread, @Lenni?


OH, Schneibo, you don't get it?........the ENTERTAINMENT you provide with all your rants about how everybody who doesn't believe in your concept of Perpetual Motion is a #physicscrank.

Oh, by the way, would you digress in a cogent manner how your CONSERVATION OF GRAVITY concept works? Just how does matter convert (transform) to GW energy? You keep this such a big secret......don't you want a Nobel Prize for Physics?
Da Schneib
4.3 / 5 (11) Sep 30, 2017
@Lenni, if you have the false impression that I am reading anything you say, you should consider that I don't bother with that very often and almost everything I do bother with turns out to be you mindlessly trolling for a response. The only reason I'm posting this time is because you posted, not because of anything you said.

Obviously I only bother with you when I'm bored.

I ask again, why are you posting on this thread if you don't have anything to say about open scientific data other than to denigrate it because it shows you're lying again?
greenonions1
4.3 / 5 (11) Oct 01, 2017
...it was believed... that some rogue analyst could claim existence of something that wasn't really there.
So? Doesn't the up side - far outweigh the danger? Some rogue analyst could spot something in the data - and physics would move forward. These are publicly funded projects. Don't we all own this data? Surely the control of the data in this way - validates the conspiracy theorists. "You are all too stupid to understand - so we have to protect you!" I hope they continue forward with more and more open access.
Benni
1.4 / 5 (10) Oct 01, 2017
I ask again, why are you posting on this thread


......and I keep telling you it's about the ENTERTAINMENT FACTOR you provide with your Perpetual Motion theories about things like CONSERVATION OF GRAVITY, and on & on goes the list.

The #physicscranks populating the Commentary here are none other than neophytes like yourself, Shavo, Jonesy, etc, who have weirded out concepts about the content of Special & General Relativity but won't produce the relevant sections to back up your claims for the content you claim exists there.

For example you have put up dozens of posts that Einstein in General Relativity laid forth the concept for black holes, when I challenge you to produce the relevant section of GR to back up your assertion & I provide the link to "On Stationary Systems with Spherical Symmetry consisting of many Gravitating Masses" in which Einstein completely trashes Schwarzschild BH math, all you do is go on name calling rants. Yeah, great ENTERTAINMENT.
ditty00
5 / 5 (8) Oct 01, 2017
It's a shame that the users commenting have very little to say about the article. I remember a time on this website when the personal vendettas didn't exist and the comments actually has something to do with the articles.
Unfortunately, I have to tolerate all the bickering and annoyances between all the heavy posters because this is one of the few sites that have interesting articles. Are all of you so insecure with your own beliefs that you have to belittle everyone that disagrees with you?

Anyway, I think that open data like this is a good thing. It allows scientists and those interested in the data to comb through it for their own reasons to see what they can find. Yes, it may bring out some that completely misinterpret the data, but that will be discovered in time by those that actually understand it and in the process maybe those that are incorrect will learn something.
rrwillsj
1 / 5 (1) Oct 01, 2017
Come on now! All along I thought I was the comedic foil on this site.

Still, I am feeling kinda smug with the recent spate of research findings. My bloated ego interprets as supporting speculations that the concept of a chaotically messy cosmos at this early stage of the universe. Are possibly reasonably accurate description of the fundamental reality of existence as a crapshoot.

You all make up all sorts of rules for the universe to obey. Then turn on each other for failing to concede the correctness of your awesomeness.

Frankly and Ernestly, my suspicion is that over the next few hundred billion years, we will all be proven wrong.
HeloMenelo
4.6 / 5 (10) Oct 02, 2017
Aaah antigoracle socks benni,realitycheck climbing the ladder of dumbness.... again, (or is that stepping down the ladder lol ) These clowns are definatelty here for the entertainment, as they are providing the entertainment :D, the ringmasters here always slap their silly hides so they keep on squeling and chest thumping doing their monkey business.. priceless :D
HeloMenelo
4.6 / 5 (10) Oct 02, 2017
Thread where @RC lies about current research into cosmic voids and gets caught: https://phys.org/...ies.html

There are so many lies they won't even fit in one post. More coming in 3 minutes.

Priceless :D

6 love... ;) again lol
RealityCheck
1 / 5 (4) Oct 02, 2017
@Da Schneib.
....and @RC are against public release of data sets by real scientists. It makes it easier to tell when they're lying.
Why lie so brazenly, DS? Have you no shame or sense at all? I am not against what you aid, I am against you repeatedly misleading/pretending while being incorrect. You are worse than many of those whom you attack; since you should (and claim to!) know better than lie and attack while being ignorant of the facts (because you don't read or just pretend to understand and make obviously incorrect statements about what you misread/ignored. Lying like that is only making you less trustworthy, DS. Try to be more trustworthy, mate. Stop lying/spamming about me and try harder to listen/learn instead. OK? :)
RealityCheck
1 / 5 (4) Oct 02, 2017
@HeloMenelo.
Aaah antigoracle socks benni, realitycheck...
Mate, you're way off base with that about me being antigoracle sock. :) Whether anyone else here is an antigoracle sock, I obviously and demonstrably am not. Have you seen my exchanges with antigoracle in the past? If you had, you wouldn't have made a mistaken-identity faux pas like that. Please get your facts straight next time, ok? Thanks. :)

ps: And what you obviously don't know is that I hyave had to correct DS many times over the yearsl; so all his spamming/linking is futile because the careful reader will check and see for themselves the truth of the matter in ALL those cited instances. So, mate, don't believe just because you're biased; check out the facts before adding to the problem of untrustworthiness in those who use such tactics as those you and DS are trying on (again) against me. Won't work anymore. Get a new 'act', mate! :)
Da Schneib
5 / 5 (1) Oct 03, 2017
@ditty, when I see the bullied kid show up at school with a gun and shoot a couple bullies, I have to say that my sympathy is with the bullied kid. The bullies' parents always have a story about how nice the bully was. I generally ignore that BS. Kids who support bullies risk their lives and every parent should tell them so. Kids who bully risk their lives and every parent should recognize this behavior pattern and tell them they're going to die badly if they don't stop. Movies reinforce the violent reaction to bullies. They should shut up and either die or stop bullying.

Think of it as evolution in action.

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