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Antiproton Orbiting Helium Ion
- deleted 5y ago[deleted]
- londons_explore 5y agoCould this lead to a storage mechanism for anti-protons?
- fsh 5y agoAntiprotons can be stored pretty much indefinitely (many years) in cryogenic Penning traps. This is done by the BASE collaboration at CERN [1] who are actually neighbors of the group that the article is about. [1] https://base.web.cern.ch/ https://base.web.cern.ch/
- ethbr0 5y agoCERN: the only place you can pop over to your neighbor to ask for a cup^H^H^Hstream of antiprotons.
- ISL 5y agoI don't think they're presently operating the antiproton source, but for decades one could get them at Fermilab, too. https://www.fnal.gov/pub/tevatron/tevatron-operation.html https://www.fnal.gov/pub/tevatron/tevatron-operation.html
- zardo 5y agoCould it lead to a new storage method? Helium lasts for microseconds, perhaps other atoms can store it indefinitely. Could that enable bulk antimatter storage? E.g. 1 mol of mercury that contains 1 mole of anti-protons and doesn't annihilate unless subjected to some extreme condition.
- scrumbledober 5y agoThis seems like something that wouldn't even be written about in sci-fi books because it just doesn't make sense to ever be possible. It seems impossible to even imagine the implications. I also can't imagine future chemistry students needing to memorize two separate sets of electron and antiproton orbitals.
- Pulcinella 5y agoNote that this isn’t the first time these kind of “exotic” atoms have been created. https://en.m.wikipedia.org/wiki/Exotic_atom https://en.m.wikipedia.org/wiki/Exotic_atom https://en.m.wikipedia.org/wiki/Antiprotonic_helium https://en.m.wikipedia.org/wiki/Antiprotonic_helium https://en.m.wikipedia.org/wiki/Antihydrogen https://en.m.wikipedia.org/wiki/Antihydrogen
- datameta 5y agoAlso of note is the fact that this is the first time they were able to get data granular enough to be of use.
- gus_massa 5y agoFrom Wikipedia: https://en.wikipedia.org/wiki/Antiprotonic_helium https://en.wikipedia.org/wiki/Antiprotonic_helium > The antiproton can thus orbit the nucleus for tens of microseconds, before finally falling to its surface and annihilating. From the research article: https://www.nature.com/articles/s41586-022-04440-7 https://www.nature.com/articles/s41586-022-04440-7 > The resonance parent states (37, 35) and (39, 35) have microsecond-scale lifetimes, whereas the daughter state (38, 34) has an Auger width ΓA ≈ 21 MHz (ref. 7; Fig. 1b) The life of the antiproton here is too short to make an interesting chemistry experiment, but it's long enough to measure the spectral lines.
- ethbr0 5y agoDumb question: Why does the antiproton fall to the nucleus' surface, after orbiting?
- tlogan 5y agoQuestion: would antiproton with antielectron orbiting around it be stable as normal hydrogen atom? Did somebody made an experiment like that?
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- Pulcinella 5y agoYes. It should be indefinitely stable as long as it does not come into contact with regular matter. https://en.m.wikipedia.org/wiki/Antihydrogen https://en.m.wikipedia.org/wiki/Antihydrogen
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- nuccy 5y agoIf antimatter was created during the Big Bang (and it was, we actually just don't know why there is more matter than antimatter [1]) it could exist in issolated-enough patches of the Universe. Photons, gravitational waves or neutrinos coming from those regions would not differ in any way, so we would not be able to identify those regions, up until they merge with normal-matter-filled ones (which is unlikely due to accelerated expansion of the Universe [2]). 1. https://home.cern/science/physics/matter-antimatter-asymmetry-problem https://home.cern/science/physics/matter-antimatter-asymmetr... 2. https://en.m.wikipedia.org/wiki/Accelerating_expansion_of_the_universe https://en.m.wikipedia.org/wiki/Accelerating_expansion_of_th... Edit: as a matter of fact experiments, like the one described in the posted paper, allows to shed some light on the properties of antimatter and why there is more matter in the Universe (matter-antimatter anisotropy).
- jl6 5y agoWhat a bummer - to send an intergalactic probe to a far-off supercluster only to find it’s made of antimatter and you cannot interact with it (if you survive the close encounter long enough to find this out).
- fasteddie31003 5y agoSo could we make a rocket engine out of this? We would need to store antiprotons and then shoot them at helium, right?
- zardo 5y agoNothing special about helium if you want to make a rocket, any matter will do. The difficulty is in the creation and storage.
- croddin 5y agoThis makes me wonder, if we had a significant amount of anti-hydrogen (but not enough to make a star), what would be the most complicated thing we could build out of it, and how would we go about doing so? (I also asked on: https://physics.stackexchange.com/questions/699258/building-things-out-of-antimatter https://physics.stackexchange.com/questions/699258/building-...)
- nynx 5y agoI’m not sure what you mean by enough to make a star. Stars don’t have antimatter in them.
- renewiltord 5y agoOne would expect a sufficiently large amount of antihydrogen to form an antistar.
- vba616 5y agoThere was an old science fiction story where the first interstellar expedition discovers that the entire universe except for the solar system is antimatter. The hard way, when they try to land on an alien planet. Only it was written at some point in time between the concept being invented and the current terminology so they didn't call it antimatter. (I think it may be "Minority Report", written in 1949 by Theodore Sturgeon and not related to the Tom Cruise movie which seems to be based on a Phillip K Dick story of the same name)
- croddin 5y agoI just mean that most elements besides hydrogen are made in stars, theoretically with a very large amount of hydrogen you could make an antimatter star, but without doing that, what elements, molecules etc would we be able to make, if we had access to a large amount of anti-hydrogen that was contained so that it would not annihilate with our matter.
- chasil 5y agoPositive beta decay can and does happen, so while this assertion is correct for all intents and purposes, it is not strictly accurate. One of the potassium-40 decay paths is the emission of a positron, and this does happen in the human body. Stars with potassium-40 metalicity would see this beta decay as well. "Very rarely (0.001% of events), it decays to 40Ar by emitting a positron (β+) and a neutrino." https://en.wikipedia.org/wiki/Potassium-40 https://en.wikipedia.org/wiki/Potassium-40
- Robotbeat 5y agoMuons can do something similar, and it has the effect of reducing the effective radius of the atom, which can catalyze fusion. Which makes me wonder… is antiproton catalyzed fusion a thing? Does the antiproton last long enough? Muons are inefficient to produce. Can antiprotons be made significantly more efficiently?
- ben_w 5y agoI’m not sure about antiproton catalyzed fusion, but I have heard of antiproton induced fission induced fusion: https://space.nss.org/wp-content/uploads/Space-Manufacturing-conference-13-069-Antimatter-Initiated-Microfission-Fusion.pdf https://space.nss.org/wp-content/uploads/Space-Manufacturing...
- marcosdumay 5y ago> is antiproton catalyzed fusion a thing? I imagine on any geometry you can create the anti-proton will be absorbed by the nucleus much quicker than another nucleus can. On what is easier to produce, currently muons are much easier.
- ISL 5y agoIt is much more difficult to produce antiprotons than muons. Furthermore, my guess is that the proton-antiproton annihilation rate is much faster than the rate of antiproton-catalyzed fusion. Muon catalysis doesn't have the annihilation channel (the heavy negatively-charged particle is always close to one H/D/T nucleus), so it will catalyze fusions all day until it decays. The antiproton can simply annihilate. That said, antiprotons probably would catalyze fusion at some rate. Whether it is higher or lower than muon catalysis, I'm not sure. If the antiproton orbital radius is too small, it may actually lower the capture cross-section for a neighboring hydrogen, even if the post-capture fusion cross-section is (almost certainly) higher.
- jesuslop 5y agoSeems it'd have to be ultra-hot and ultra-cool at the same time
- shirro 5y ago
- amelius 5y agoHow close does an anti-proton have to come to a proton to become annihilated? And, when a ball of matter and anti-matter collide, will they completely annihilate, or will the initial impact blast them apart such that parts will stay intact? Does initial speed matter? Would we be able to partially annihilate a proton?
- hexo 5y agoAntiparticles have oposite quantum numbers, so it means they also have oposite electric charge. Basicaly, they would attract as much as possible and, you know, kaboom. This is a compostite particle made of quarks, which under annihilation produce their gauge particles - gluons. These quickly undrego hadronization - will pair-up to produce mesons. These are unstable af so they decay. Ultimate fate is photons, electrons, positrons and neutrinos. Even, antiproton can annihilate with neutrons, which makes sense given similar internal structure. Keep in mind that during conversions energies are preserved. So that when lighter particles are produced, they move faster. So yes, it would be ripped apart, kind of.
- amelius 5y ago> Antiparticles have oposite quantum numbers, so it means they also have oposite electric charge. Basicaly, they would attract as much as possible and, you know, kaboom. This is true, but an electron and nucleus also have opposite charge, yet the electron typically doesn't drop into the nucleus all the time.
- amelius 5y agoLooks like semiconductor physics is about to get more interesting. Now we have electrons, holes, and antiprotons ...
- AnimalMuppet 5y agoYou do not want antiprotons in your semiconductors. They will orbit much more tightly than the electrons; there is nonzero overlap of their wavefunction with the protons in the nucleus. There will be interactions (annihilations), and those will not be good for your semiconductor device.
- jmyeet 5y agoSo a free neutron will decay into a proton and an electron. This already confuses me because the only difference between the nucleons is an up quark (uud vs ddd) and an electron an a lepton is a fundamental particle. But an electron in an atom won’t merge with a proton to form a neutron. There seems to be some hand waving here around the strong nuclear force and zero energy state that I don’t really understand. But in a neutron star the forces are so great that I believe this can happen (or how else does neutronium form?). And now we see an antiproton can annihilate a proton. Doesn’t this have the same zero energy problem? Can someone ELI5?
- ladams 5y agoWorth noting that a neutron decays into a proton, an electron, AND an electron anti-neutrino, so that lepton number is conserved (electron is +1 and anti-neutrino is -1). This interaction conserves charge and baryon number as well.
- myself248 5y agoITYM ELI27....
- vba616 5y agoELITTCCCAHEM Explain-like-I-took-three-college-calc-courses-and-hated-every-minute
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- vikingerik 5y agoElectrons in an atom do merge with a proton to form a neutron. https://en.wikipedia.org/wiki/Electron_capture https://en.wikipedia.org/wiki/Electron_capture
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- kurthr 5y agoOk, now have a bosonic anti-alpha (two neutrons and two anti-protons) orbit in a He4 Bose Condensate!
- Pxtl 5y agoSo when the antiproton orbits a helium nucleus, does it occupy the same states and levels an electron would? Does it do it in a more concrete way, since it's more massive? I thought the wavicleness of matter was inversely related to its mass, and an antiproton is massive enough to be more particly.