LHC sees its first collisions!

By Phil Plait | November 23, 2009 3:13 pm

Edited to add: My Hive Overmind compatriots at Cosmic Variance have more details.]

lhc_1stcollision_atlasHey, is the Earth still here? Because the Large Hadron Collider saw its first proton collisions today!

OK, it wasn’t at full power, and this is just a preliminary test, but still: It works!

In the graphic above (click to get the whole thing, plus others) shows the particles detected in the ATLAS experiment, one of the two big detectors on the LHC. The paths of the particles are shown, and they all trace back to one spot (or close enough), indicating they all emerged from the same patch of space inside the collider, just as you’d expect if they were the products of a subatomic collision.

There’s still a long way to go, but this was a very important step along the way. Congrats to everyone at CERN!

CATEGORIZED UNDER: Cool stuff, Science
MORE ABOUT: LHC

Comments (51)

  1. CB

    Can we get them to move the full power collisions after the series finale of Lost? Would hate to miss that.

  2. Charlie Young

    Can’t wait until the black holes form…

  3. Doug Little

    Hang on where is the sabotage from the future?

  4. Ld Elon

    Is this news or wishful thinking equating to a regular blog?
    Also this story has only a few words, which seems completely ridiculous, being of the weight of thee issues that stand.

  5. Sharkweek

    I thought I felt the world almost ending.

  6. amstrad

    If you can detect a particle via some detector, aren’t you changing its velocity? How can you say where it came from if the first detector scattered the particles path?

  7. Gary Ansorge

    5. amstrad

    “If you can detect a particle via some detector, aren’t you changing its velocity?”

    Yes!

    How can you say where it came from if the first detector scattered the particles path?

    What??? Nothing was said about impacting a first detector. What WAS said was that there were two detectors and the one called ATLAS was responsible for this detection/analyses.

    Reading is one thing. Comprehension is something else.

    GAry 7

  8. Kevin F.

    @CB Dharma probably has a collider somewheres on the island. :)

  9. John

    So what are the Vegas odds that the LHC will break down before the first full power test?

  10. amstrad

    @Gary7

    According to the diagram (which is probably an oversimplification), each particle produced in the collision passes through four layers of detectors. What I’m saying is: how can you tell the initial angle of incidence? Using just the first two layers and extrapolating a straight line implies that the first layer did not deflect the particle.

  11. (add generic LHC induced apocalyptic event comment here)

  12. IVAN3MAN AT LARGE

    Hmm… I wonder how many little universes were destroyed today? ;-)

  13. Sili

    Silly physicists.

    They forgot to remove all their Post-It notes before assembling the detector. That must be embarrassing.

  14. Scott

    “Hey, is the Earth still here?”

    Let me check

    *Opens blinds and looks out window*

    Yep, looks like it’s still here. :)

  15. Jar Jya Binks Killer

    Cool! :-)

    Did they blow up the Earth yet?

    Where’s my planet-swallowing black hole? ;-)

  16. uknesvuinng

    Suck it, saboteurs from the future!

  17. Jar Jya Binks Killer

    Off topic but BA are you going to post about the recent leaked /hacked emails revelations on the whole Global Warming Alarmist CRU lobby soon? I’d love to see what you make of the breaking news here that seems to show massive manipulation, politicising & misuse of purported “science”, even arguably criminal fraud on the part of the Warmers.

    For some of these emails etc .. & plenty of links & commentary see:

    http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/hadley_hacked

    PS. & before anyone mentions the “RealClimate” website please note that RC is among the Alarmist groups and individuals that have just been exposed & discredited by these emails.

  18. Jar Jya Binks Killer

    An excellent summary (& funny Utube clip) on the Alarmists leaked emails etc .. is here:

    http://motls.blogspot.com/2009/11/hacked-hadley-cru-foi2009-files.html

    Well worth a look.

  19. Spectroscope

    See also “All Your Emails Are Belong To Us” parody clip:

    http://www.youtube.com/watch?v=3SWAytBHG90&feature=player_embedded

    These emails are devastating to the Warmer hysterics cause. Perhaps we’re watching the beginning of the end for the Global Warming Alarmist lobby here? :-)

  20. GPilot

    @amstrad You have a valid questions. The diagram clearly shows red ‘beams’ passing thru more than one detector plate. You’d need two flat plates, minimum, to get a velocity approx. More to see any curve.

    Anyway, I’d love to better understand how these detectors work without changing the velocities of the particles

  21. M31

    “I felt a great disturbance in the Force, as though millions of voices cried out in terror, but then said, ‘Oh, never mind, then.’”

  22. Spectroscope
  23. Ian

    Shazam! I wonder if one can volunteer at CERN to fight off the sabateurs from the future?

  24. Yes, I completely trust a hacker a person who by nature has to do devious things. Is there any verfication of these e-mails? What was the motivation of the hacker? Was the hacker paid by anyone for this? Was it for petty revenge?

  25. @Jar Jya Binks Killer
    Hacking files and selective quote mining couldn’t posibly be used to push forward an agenda that is losing ground in peer reviewed journals…
    http://bipedalia.wordpress.com/2009/11/24/on-east-anglia-crus-hacked-files/

  26. jick

    @19

    “PS. & before anyone mentions the “RealClimate” website please note that RC is among the actual climate scientists that have just had their private correspondence illegally hacked and disclosed to public, out of context.

    Fixed that for you.

  27. MB

    Back to LHC physics…
    Disclaimer: I am no expert on the topic.

    @amstrad: Yes! When a particle registers in a detector (which it does by knocking something a bit – usually an electron) it’s velocity does change. The paths of the particles are extrapolated from a few measurements back to the interaction “vertex”. Also, calorimeters measure the total energy of the particle.

    The event reconstruction is an extrapolation and it is statistical in nature – there are definite uncertainties involved. These uncertainties are minimized by considering particle tracks with large energy – large energy means large momentum and large momentum means the particles are less likely to be significantly deflected in the detector. That is not much of a problem because the higher energy particles tend to be the result of the most interesting collisions anyway.

    Quantifying the uncertainties of event reconstruction (and optimizing the process) is an important part of detector calibration, which the LHC is still undergoing. The events that are happening now aren’t really probing new physics; they are just a checkout of the system to let the LHC people learn how their machine works.

    A quick google hasn’t turned up anything especially useful, but this topic is called “event reconstruction” or vertex/track reconstruction, and is the subject of a lot of study. Here are a couple of abstracts:

    http://preview.tinyurl.com/y89zuag
    http://www.iop.org/EJ/abstract/1742-6596/119/3/032033
    http://preview.tinyurl.com/ybr24no
    and a slide presentation about reconstruction algorithms:
    http://www.desy.de/dvsem/SS05/adam_talk_2005-07-11.pdf

    The short answer: Event reconstruction is a statistical extrapolation. The uncertainties are quantified and reduced by some hard core data processing algorithms and detector calibration.

  28. Just me

    Um. Protons are composed of Post-It notes??? The universe is weird.

  29. Jonathan

    @amstrad. It all depends on what detector component you’re using. The big LHC detectors consist of lots of layers of sub-detectors, each looking at different properties of particles. The innner tracking detectors generally work by the particle knocking an electron off an atom in a silicon strip. This doesn’t affect the momentum of the particle all that much so you can arrange lots of strips allowing you to reconstruct the track. Other detectors, like calorimeters, work by trying to measure the energy released in completely stopping the particle, in lead for example. Those don’t appeare to be included in the diagram.
    The CMS website (the other big detector, and one I briefly worked on way back) has a nice description http://cms.web.cern.ch/cms/Detector/index.html
    (Look at the tracker page)

  30. Bahdum (aka Richard)

    Do the post-it notes change their color?

  31. gss_000

    @Spectroscope, @Jar Jya Binks Killer

    Silly, silly deniers. Hijacking a thread just to promote bad information.

    Anyways, back to the story at hand. Forget the future. It’s the birds you have to worry about:
    http://www.universetoday.com/2009/11/06/bread-dropped-by-bird-causes-problems-for-lhc/ Hitchcock had it right.

  32. Robert

    Of course the created black hole is so small we wouldn’t notice it for a while. It dropped down to the center of the earth where by chance collisions it gobbles up an occasional atom or two. Only within a few thousand years or so will it grow large enough that we notice we just started the chain of events resulting in the destruction of the Earth.

    That is, if Hawking was wrong and it doesn’t evaporate. :P

    (A similar thing happened with a gravitational wave generator on Mars in a SF story I read a few years ago, too bad I forgot the title/author…)

  33. What happened to the kaboom? There was supposed to be an Earth shattering kaboom!!!

    Oh well, I guess we’ll just have to be satisfied with some wonderful scientific information instead.

  34. @Robert,

    Would that be Larry Niven’s “The Hole Man”? (Found thanks to a Google search.) The description I found says: “Humans have found a gravitational wave generator on Mars of alien origin, abandoned for eons. At its heart is a ‘quantum black hole’ – device vibrates it to generate gravity waves. Careless poking around has released it into the mars’ interior – mars will soon be a black hole!”

  35. Lawrence

    I believe this was also the plot of a book called “Earth” where a blackhole slipped into the Earth’s core & caused problems. It has been a while since I’ve seen a copy, so I’ll see if I can find it & post some more info.

  36. Levi in NY

    Holy crap, I think I see a Higgs boson in that picture!

    Higgs bosons look like yellow rectangles, right?

  37. Douglas Troy

    That’s great news, I have to imagine the LHC folks are exceedingly happy.

  38. ThatPirateGuy

    When will we find that this LHC is fully operational? [/Emperor]

  39. “Scientists at CERN have discovered, not the Higgs Boson, but the Higgs Post-on. Realization of their discovery had them hanging their heads in shame. Says one researcher, ‘If only we had talked to 3M first!’”

  40. JoeSmithCA

    Has anyone said this one yet? Good old Marvine the Martian:

    “Where is the kaboom? There was supposed to be an earth-shattering kaboom! This makes me very angry, very angry indeed.”

  41. Asimov fan

    @ 38. Lawrence Says:
    November 24th, 2009 at 8:17 am

    I believe this was also the plot of a book called “Earth” where a blackhole slipped into the Earth’s core & caused problems. It has been a while since I’ve seen a copy, so I’ll see if I can find it & post some more info.

    Great novel! It is one written by David Brin – and is, indeed, titled ‘Earth’ published by Futura books in 1990. It features a couple of black holes falling into our planets core along with some good science and a scientist hero. One of my favourite non-Asimov books! :-)

  42. Asimov fan

    For more on Brin’s Earth novel see via Wikipedia :

    http://en.wikipedia.org/wiki/Earth_(novel)

    It’s another novel I’d happily recomend to anyone. :-)

    Have you read it BA?

  43. Spectroscope

    @ 27. Davidlpf Says:

    Yes, I completely trust a hacker a person who by nature has to do devious things. Is there any verfication of these e-mails? What was the motivation of the hacker? Was the hacker paid by anyone for this? Was it for petty revenge?

    There is a lot of speculation that the “hacking” was an inside job and so the “hacker” may well be a disenchanted Alarmist turning whistleblower. So it is most likely someone who is sick of having to lie and distort the facts who is prompted by a guilty conscience.

    Investigations indicate the emails are genuine and even the Alarmist camp seems to be confirming this.

    @ 28. Bipedal Tetrapod Says:

    @Jar Jya Binks Killer – Hacking files and selective quote mining couldn’t posibly be used to push forward an agenda that is losing ground in peer reviewed journals…

    It can be argued that everyone has an agenda, the Warmer hysterics especially included.

    Only unlike the GW skeptics the Alarmists agenda is unsupported by the facts hence the fraudulent and unscientific manipulation of the data by the CRU as revealed by the emails incl. suppressing scientific papers contradictory to their cause and denying or preventing proper peer review – as well as Freedom of Information requests designed to obtain this info. legally.

    @ 29. jick Says:

    @19 Fixed that for you.

    No, I had it right first time. :-P

    The RC mob are discredited and exposed whether they like it or not.

    As noted above, it seems probable that the “hacking”was an inside job and more a case of whistle-blowing and its hard to find any context where the admissions revealed in the CRU emails are innocent and not what they appear.

    “Hiding the decline” using “tricks” to make it look like temperatures have warmed when they haven’t, preventing or warping peer review, censoring dissenting opinions, deleting or asking others to delete emails to cover up their tricks & this frank admission:

    “The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. ”
    - IPCC lead author Kevin Trenberth privately telling Alarmist collegaues that the data simply doesn’t show what their climate models predicted:

    All this just cannot be explained away.

    Sorry Alarmist Warmer hysterics but your goose is cooked – wonder who’ll be first to come clean & turn states evidence? ;-)

    Anyway, I wonder why you are more concerned about the ethics of those who are exposing the fraud rather than those perpetuating it? Which is the worse offence? :roll:

    @ 34. gss_000 Says:

    @Spectroscope, @Jar Jya Binks Killer
    Silly, silly deniers. Hijacking a thread just to promote bad information.

    What about the information provided is in your view bad or invalid specifically?

    Whatever you think of us Anthropogenic GH FXT Skeptics you need to look at the reality of the science and the evidence of scientific malpractice and even outright criminal fraud revealed in the emails.

    Shooting the messenger will NOT change this evidence or make it go away.

    The Alarmists have been caught doing exactly what the creationists do – tailoring their “evidence” to match their pre-ordained conclusions rather than changing their conclusions to match the evidence. This is unscientific and proof that the Warmer Alarmist ideology is more a religion than a science.

    If you disagree then you’ll have to back up your assertions properly rather than just indulge yourself in ad hominam attacks.

    PS. No post on this yet BA? Don’t you think you should be covering this massive story which has key elements of science, (the green) religion & ideology imposing itself on science and the political misuse of science? Your choice and your blog of course but I really feel you should be discussing this and fail to see why you haven’t done so yet. Not too beholden to the “watermellon greens” (Deep environmentalist “Green” on the outside, deep socialist/communist “Red” on the inside) I hope? :-(

  44. Paul M.

    gss_ooo

    The birds are from the future… even Hitchcock didn’t see that coming.
    Damn, now I can’t go outside

  45. About leak: nice to see that some persons are soo “sceptic” that they are now in frenzy.

    Putting aside lack of guarantee that these emails and other data was not tampered in any way by hacker (they are already selected)… this is too much of everything, so I will comment about one thing. Tricks.

    Spectroscope: “…using “tricks”…”
    Check with dictionary this word. No, not only first meaning. This should do the trick. :> Anyway, learning more about tricks of trade from climate sciencists should be interesting. Not to mention these tricks…
    http://math.about.com/library/bldivide.htm
    http://en.wikipedia.org/wiki/Partial_fraction#General_result
    http://en.wikipedia.org/wiki/Methods_of_contour_integration#Example_.28IIIa.29_trigonometric_integrals.2C_the_general_procedure

    In other words, “Scientists often use the term “trick” to refer to a “a good way to deal with a problem”, rather than something that is “secret”, and so there is nothing problematic in this at all”.

    So this sentence about “tricks” from Spectroscope…
    “…using “tricks” to make it look like temperatures have warmed when they haven’t…”
    This is not even selective quote mining, this is outright insinuation and lie. As expected from denialists, as always.

  46. ND

    Spectroscope,

    “There is a lot of speculation that the “hacking” was an inside job and so the “hacker” may well be a disenchanted Alarmist turning whistleblower. So it is most likely someone who is sick of having to lie and distort the facts who is prompted by a guilty conscience.”

    Is there any shred of evidence behind this speculation?

    Is there any confidence that any of the emails are not tempered with? A few in a sea of legit emails would be very effective.

  47. oki

    Is there somewhere we can find out what all the stuff in the picture represents? Like those orange things on either end. Are those.. magnets..? It’d be so interesting to know.

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

ADVERTISEMENT

See More

ADVERTISEMENT
Collapse bottom bar
+

Login to your Account

X
E-mail address:
Password:
Remember me
Forgot your password?
No problem. Click here to have it e-mailed to you.

Not Registered Yet?

Register now for FREE. Registration only takes a few minutes to complete. Register now »