8 ms·

What happens if you stick your head in a particle accelerator? (2017)

• deleted 5y ago
  [deleted]
• matthberg 5y ago
  This seems to be a paywalled/rate limited copy of an article from aeon.co by the same author: https://aeon.co/ideas/why-we-can-stop-worrying-and-love-the-particle-accelerator https://aeon.co/ideas/why-we-can-stop-worrying-and-love-the-...
  • dang 5y ago
    Ok, we've changed the url from https://www.theatlantic.com/science/archive/2017/01/what-happens-when-you-stick-your-head-in-a-particle-accelerator/512927/ https://www.theatlantic.com/science/archive/2017/01/what-hap... to the one it points to.
• dj_mc_merlin 5y ago
  I guess that makes sense. A lot of energy, but relatively little impact area for that energy to be transferred. Not that physics at that scale makes intuitive sense. I hope he taught after the incident, I do not think there would be a better professor story than "let met tell you about when I put my head in the particle accelerator!"
  • LeoPanthera 5y ago
    From Wikipedia: "Bugorski continued to work as a physicist at the Institute for High Energy Physics and held the post of coordinator of physics experiments. Because of the Soviet Union's policy of maintaining secrecy on nuclear power-related issues, Bugorski did not speak publicly about the accident for over a decade. He continued going to the Moscow radiation clinic twice a year for examinations and to meet with other nuclear accident victims. He was described as "a poster boy for Soviet and Russian radiation medicine". In 1996, he applied unsuccessfully for disability status to receive free epilepsy medication. Bugorski showed interest in making himself available for study to Western researchers but could not afford to leave Protvino."
    • dj_mc_merlin 5y ago
      Thanks, I guess. I wish I hadn't known that though.
      • atatatat 5y ago
        Do you also wish someone had censored Bambi's mother's death?
• changoplatanero 5y ago
  I knew that particle accelerarors require a vacuum to operate so at first I didn't understand how you could stick your head in one without releasing the vacuum and stopping the accelerator. It turns out that the vacuum is only needed to accelerate the particles and then after that they can pass through normal air as they make their way to the sensors.
  • cperciva 5y ago
    Indeed. So the technical answer to "what happens if you stick your head in a particle accelerator" is "nothing, since without a vacuum particles can't be accelerated to high speeds" -- the question answered by the article is "what happens if you stick your head in a beam originating from a particle accelerator".
  • jamesmaniscalco 5y ago
    As an accelerator physicist - while some earlier machines were built without vacuum beamlines, nearly all modern[0] accelerators are built with ultra-high vacuum beamlines. Beam quality greatly degrades in contact with residual gas due to scattering. This is especially important in light sources, but really any machine where you want low emittance. [0] edit - I should specify that I mean high energy machines here (my focus). There are also many low energy machines that don't require high vacuum at the end - medical accelerators for example.
  • tgsovlerkhgsel 5y ago
    How do you get the particle out of a vacuum area into a non-vacuum area?
    • jasonwatkinspdx 5y ago
      Probably just a very small hole and beefing up the vacuum equipment near it. From what I recall the LHC beam is on the scale of a couple micrometres.
      • zaarn 5y ago
• goldenkey 5y ago
  Particle accelerators aside, the quote at the end is a bit of an overstatement: "And as frightening and awesome as the inside of a particle accelerator might be, humanity has thus far survived the nuclear age." I'm not sure if Ouchi would agree... https://en.wikipedia.org/wiki/Tokaimura_nuclear_accident https://en.wikipedia.org/wiki/Tokaimura_nuclear_accident https://historyofyesterday.com/the-man-kept-alive-against-his-will-647c7a24784 https://historyofyesterday.com/the-man-kept-alive-against-hi...
  • dj_mc_merlin 5y ago
    Poor man. But, uh.. are you and everyone you know dying of fireballs and/or radiation poisoning? If not, you are the one making the clear overstatement.
  • kelnos 5y ago
    Those two articles are somewhat in conflict. The latter makes it sound like the doctors were doing experiments on Ouchi, while the Wikipedia article's tone seems more in line with a medical team trying to save him. It also mentions that the doctors were instructed to try to resuscitate him (after multiple heart failures) by his family, but the second article makes it sound like they were doing it on their own, to try and prolong his life so they could study him. Which is right?
    • kbelder 5y ago
      The rule of thumb is, whichever is least sensational is probably the truth.
      • goldenkey 5y ago
        That's not a rule of thumb. That's what idiots use as a measuring stick when they can't bother to do any research themselves. Common Self-Ascribed HN Logician: "Wow, the Wuhan lab leak sounds CrAzY!! CNN is telling me it's a whacko conspiracy theory by our CrAZy SeNsAtIoNaL PrEsIdEnT! Checkmate, Mister Frump!! Crazy things don't happen! RuLeS of ThUmB!!"
  • 5y ago
• 01100011 5y ago
  Doesn't anything greater than... was it 6MeV or 12MeV result in radioactive activation of stable isotopes? I think he would have gotten quite a dose initially, but then the activated atoms would have continued to decay, extending the dose.
• snet0 5y ago
  It's so strange to me that the brain could be so damaged as to lead to facial paralysis and deafness, as well as seizures, but still function well-enough for the person to complete their doctorate. Did he just get unlucky, and receive a precise zap to the "right side of the face" zone? Or did the brain have to adapt under stress, and decided that this functionality was the sacrifice that had to be made?
  • klipt 5y ago
    The brain is very plastic. Which is why often the first sign of a brain tumor (including in people working mentally intensive jobs like PhD student) is a seizure, or paralysis, or deafness. All signs that plasticity in some part of the brain has reached its limit.
    • exit 5y ago
      i don't follow from this why plasticity reaching its limit in some part of the brain manifests overtly as seizure/paralysis/deafness. those sound more like existing pathways being disrupted, as opposed to the ability to form new pathways being inhibited?
      • klipt 5y ago
        A tumor can get surprisingly big without being noticed because the brain just routes around the damage as the tumor grows. Until it no longer can.
  • relax88 5y ago
    Steven Keating is another incredible example of what the human brain is capable of. He was very successful doing research at MIT even did a few TED talks after having nearly half his brain removed. Unfortunately he is no longer with us. https://news.mit.edu/2019/celebrating-curious-mind-steven-keating-0722 https://news.mit.edu/2019/celebrating-curious-mind-steven-ke...
  • bumblebritches5 5y ago
    fuckin burn! damn
• version_five 5y ago
  Could someone with a nuclear physics background weigh in: so there is a certain level of energy in the particle beam, that as I understand refers to the mass or equivalently energy of the particles. How does this translate to total energy deposed inside tissue? There is firstly the question of rate (power), like how many XX MeV particles per unit time are in the beam? And then second, how likely are these to interact with human tissue? Is it all of them that are absorbed, is it almost none? If someone had a microwave beam of a certain wattage aimed at their head, it is possible to calculate the total absorbed energy and estimated the heating. Is heating the main mechanism for damage with a particle beam too, or is it the ionizing effects? If it's the latter, is it more a radiation exposure problem? If so, how would be frame this in term of Siverets (sp?) or whatever the relevant unit is, and compare it to background and to other medical procedures that use radiation?
  • Retric 5y ago
    I doubt you’ll get an answer from a particle physicist. The most important factors are energy per particle, number of particles, width of beam, and is it matter or antimatter. The most general case is it’s going to bore right through you, so cancer and heating is a lesser concern than the gaping hole. A microwave beam is a different story, but again the specifics make a huge difference. A microwave oven isn’t going to do much though heating the eyeballs can cause issues. Cancer isn’t a serious concern, but boost the power enough and you can get serious and eventually fatal burns.
  • heisenzombie 5y ago
    I think the energy deposited is almost all just from the kinetic energy of the particles. The U-70 Synchrotron from the article produced 76 GeV protons. Electron-volts (eV) are a unit of kinetic energy. That works out to 0.012 microjoules per proton. This was a pulsed machine, with a repetition rate of 0.11 Hz (9 seconds between pulses). In one pulse there were 1.7×10^13 protons. That adds up to about 200 kJ per pulse: About the same kinetic energy as a Toyota Corolla (1200kg) travelling at 65km/h. As for exactly how the interaction would happen: The particles would have bounced around the atoms in Mr Bugorski's head. They would lose energy I think mostly via interactions with atomic electrons. As they decelerated, they would also throw off Bremsstrahlung photons which would create a pencil-beam of x-rays. At that energy there would also be plenty of nuclear interactions which would tend to produce neutrons and prompt gamma rays. Not all of the kinetic energy in the pulse would have been absorbed by Mr Bugorski's head. The energy deposited into a medium by a proton beam is described by the Bragg Peak. If you look it up, protons of ~200MeV would be almost entirely stopped by a human head (~20cm). But at almost 400 times that energy, I think a large fraction of the kinetic energy would just come out the other side in the form of neutrons, gammas, x-rays, and slightly slowed protons.
• DennisP 5y ago
  I used to be friends with a physics grad student at my local university. He showed us their particle accelerator, in an underground room with the control room above. He said if a certain light and siren went off we had thirty seconds to get out. They installed that after someone fired the accelerator while someone else was in the room, and seriously hurt the guy. He didn't know anything was happening at the time but ended up losing a couple limbs.
  • nomoreplease 5y ago
    > He didn't know anything was happening at the time but ended up losing a couple limbs. Surely that would have been reported by the university (PR, damage control) and in the news? Can you confirm?
    • redis_mlc 5y ago
      FYI: the human body redirects blood flow for internal organ use after various forms of trauma or infection, sacrificing the limbs, usually 2 or 4. Typically it takes a week or two before doctors cut them off. That's more likely than his limbs being left behind on campus.
    • DennisP 5y ago
      He told me about it back in the early 90s, and it had happened years before that, though I don't know how many. A quick google doesn't bring anything up, but a local newspaper would have had to put their old archives online without paywall.
  • voldacar 5y ago
    I'm not sure I understand - how did the injured man actually place himself in the path of the particle beam? Given that particle accelerators are a sealed vacuum environment? Or could you be harmed by simply standing next to the accelerator while it's operating? If so, how is that energy reaching you?
    • zaarn 5y ago
      For experiments, it's not unusual that the actual test is taking place in atmosphere. There is no issue as you can simply put a solid metal cap on the end of the accelerator and the beam will just blast through it with no issue and the atmosphere isn't going to slow it down significantly over the next few meters.
• badsfsdf 5y ago
  No mention of the Therac-25?
• fellowbard 5y ago
  Yes. Which reminds me of the old joke: Q. What happens if you stick your head up your ass? A. You die.
• deleted 5y ago
  [deleted]
• lettergram 5y ago
  > Bugorski survived, completed his PhD, and continued working as a particle physicist.[4] There was virtually no damage to his intellectual capacity, but the fatigue of mental work increased markedly.[2] Bugorski completely lost hearing in the left ear, replaced by a form of tinnitus.[5] The left half of his face was paralyzed due to the destruction of nerves.[1] He was able to function well, except for occasional complex partial seizures and rare tonic-clonic seizures. https://en.m.wikipedia.org/wiki/Anatoli_Bugorski https://en.m.wikipedia.org/wiki/Anatoli_Bugorski