[HN Gopher] What could explain the gallium anomaly?
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What could explain the gallium anomaly?
Author : ars
Score : 95 points
Date : 2024-07-12 18:35 UTC (4 hours ago)
(HTM) web link (www.quantamagazine.org)
(TXT) w3m dump (www.quantamagazine.org)
| CamperBob2 wrote:
| Photo caption: _In the lab that houses the BEST experiment, fish
| serve as an early warning system about any leaking radiation._
|
| Never change, Russia. Never change.
| dylan604 wrote:
| You can't get them all right. To be fair, they used pencils
| while NASA spent time and money to have a pen that writes in
| 0g.
| spankalee wrote:
| That's just a myth, you know:
| https://www.scientificamerican.com/article/fact-or-
| fiction-n...
| dflock wrote:
| Fischer made the space pen as a commercial product, all R+D
| entirely at their own expense. NASA just bought some of the
| pens from them.
| Etheryte wrote:
| This is a myth, using a pencil in space isn't clever or
| thrifty, it's a disaster waiting to happen. The graphite from
| pencils breaks off in small fragments while writing and the
| fragments can create shorts in electronics and to top it off
| they're also flammable. None of those are properties you want
| to bring into a spacecraft.
| sterlind wrote:
| dumb question but how well do sharpies work in space? the
| ink diffuses through the felt tip - that doesn't require
| gravity. wouldn't that work pretty well?
|
| also crayons seem like a better bet than pencils - they're
| still flammable and prone to flaking but at least they're
| not conductive.
| mypalmike wrote:
| Your question piqued my curiosity, so I did some
| googling... Apparently sharpies do work in space, though
| NASA seems to prefer the Duro brand of marker.
|
| https://airandspace.si.edu/stories/editorial/saga-
| writing-sp...
| mrguyorama wrote:
| After Fisher, the pen company, spent their own couple
| millions to develop a pen that could write in zero gravity,
| they convinced NASA to use it, and a few years later the
| Soviets bought 100 of them for their own space program.
|
| NASA was never involved in the development of the space pen,
| though they supposedly had their own effort that was quickly
| abandoned as it got expensive. Before that they also used
| pencils.
|
| The pen is just a better writing implement in space. It cost
| $3 in the 60s, with wide availability.
| sterlind wrote:
| coal miners carried canaries to warn of CO. chemical weapons
| workers brought bunnies in cages to monitor nerve gas leaks.
| it's an old tradition - it's simple, and it works.
|
| though why not Geiger counters for radiation? there must be a
| reason.
| CamperBob2 wrote:
| If there's enough CO to kill a canary, you still have time to
| get to safety.
|
| If there's enough nerve gas to kill a rabbit, you still have
| time to get to safety.
|
| If there's enough radiation to kill a fish, you're a walking
| dead man... and the 'walking' part is temporary.
| dudinax wrote:
| Maybe the fish get less shielding.
| postalrat wrote:
| What if you have a potential worrisome alpha emitter
| already in water. Keeping some fish in that water might
| give you heads up when something is going wrong.
| ars wrote:
| Would sterile neutrinos as an oscillation really change anything
| about dark matter? The total mass of neutrinos doesn't change,
| just the lepton number.
| AnimalMuppet wrote:
| It might mean 20% more neutrinos exist than we think. That
| would change the total mass of neutrinos.
|
| _Much_ more interesting (and not touched on by the article as
| far as I noticed): The electron neutrino is the "partner" to
| the electron. The muon neutrino is the partner to the muon, and
| the tau neutrino to the tau. What's the sterile neutrino the
| partner to? (Or doesn't it have one, and that's what makes it
| "sterile"?)
|
| If there is a partner to it, does the partner have mass? Does
| it interact in any way besides gravitationally? If not...
| torrefatto wrote:
| IIRC, there is another quantum number, the chirality. All the
| neutrinos measured are left chiral. The sterile neutrino,
| which does not pair with other lepton, is right chiral.
| AnimalMuppet wrote:
| Is that the only possible sterile neutrino? Because if I
| recall correctly, a right chiral neutrino _cannot_ change
| into one of the other types, because of the chirality.
| (That 's why it's "sterile".)
|
| So either they aren't produced by beta decay, or they are
| but they can't be captured by gallium, or we're seeing a
| sterile neutrino in a different sense. ("Sterile" because
| it can't interact with gallium, but not sterile due to
| chirality.)
|
| If I understand, the conversion of gallium into germanium
| is exactly a beta interaction. (But I may not understand,
| because it seems to me that gallium->germanium should
| _emit_ a neutrino, not _absorb_ one.) So I have a hard time
| seeing how a neutrino could be emitted by the source, but
| not absorbed by gallium. I could more readily see it as
| saying that there 's a fourth type of neutrino that they
| cycle through, and while in that fourth state it can't
| convert gallium. But that wouldn't be "sterile" in the
| chirality sense.
| eigenket wrote:
| > If I understand, the conversion of gallium into
| germanium is exactly a beta interaction
|
| In a "standard" beta decay the neutron turns into a
| proton and emits an electron and an anti-electron
| neutrino. In this reaction its absorbing an electron
| neutrino and emitting an electron (while still turning
| the neutron into a proton). Absorbing an electron
| neutrino is pretty much equivalent to emitting an anti-
| electron neutrino.
| floxy wrote:
| >gallium->germanium should emit a neutrino, not absorb
| one.
|
| Neutron-Neutrino interaction?
|
| https://www.vivaxsolutions.com/physics/feynman-
| diagrams.aspx
| ars wrote:
| > It might mean 20% more neutrinos exist than we think.
|
| Would it though? It's not like we know neutrino mass from
| measurement, rather we estimate it from nuclear reactions
| that have occurred. The estimate would not change if a
| neutrino oscillates into a sterile one.
| ars wrote:
| > What's the sterile neutrino the partner to?
|
| It would be a very unusual partner that has no concerved
| quantum numbers, and only mass.
|
| A sterile neutrino would also imply that the neutrino is a
| Majorana particle (because it would have not quantum numbers
| that could be "anti").
| PaulHoule wrote:
| Sterile neutrinos could also be a lot heavier than regular
| neutrinos, those kind of sterile neutrinos are ideal candidates
| for explaining dark matter and the matter-antimatter asymmetry
|
| https://arxiv.org/abs/1303.6912
|
| Just as I am disappointed that "global warming" changed into
| the more ambiguous "climate change", I'm a little disappointed
| that the "right-handed neutrino" has turned into the "sterile
| neutrino". It's _really strange_ that we only observe left
| handed neutrinos and either the revelation that there is a
| hidden right-handed neutrino or that neutrinos are fully
| Majorana particles without a right-handed form would be
| absolutely groundbreaking.
|
| My take on it is that the neutrino mass term is not "physics
| beyond the standard model" but rather a "missing part of the
| standard model" and that one way or another, neutrinos hold an
| important secret, if not the important secret of the universe.
| (Note potentially three generations of right-handed neutrinos
| could exist at three mass scales and explain the gallium
| anomaly, cold dark matter, and the rarity of antimatter)
| Terr_ wrote:
| > sterile neutrinos
|
| It's funny when one encounters serious real-world discussion on
| something previously seen as sci-fi technobabble.
|
| In this case, I'm thinking of the Destiny universe, such as this
| apocalyptic alert from a military AI. [0]
|
| > Multiple distributed ISR assets report a TRANSIENT NEAR
| EXTRASOLAR EVENT. Event duration ZERO POINT THREE SECONDS. Event
| footprint includes sterile neutrino scattering and gravity waves.
| Omnibus analysis detects deep structure information content (nine
| sigma) and internal teleonomy. No hypothesis on event mechanism
| (FLAG ACAUSAL). Bootstrap simulation suggests event is DIRECTED
| and INIMICABLE (convergent q-Bayes/Monte Carlo probability
| approaches 1). No hypothesis on deep structure encoding (TCC/NP-
| HARD).
|
| ______
|
| > In the lab that houses the BEST experiment, fish serve as an
| early warning system about any leaking radiation.
|
| I'm curious how this works, it looks as if there's one central
| underwater valve and two above-water valves, perhaps supposedly-
| breathable air is getting bubbled up through the tank?
|
| > SAGE used a tank of 57 metric tons of gallium.
|
| Some napkin-math [egregious mistake corrected] to visualize how
| much that is, and I get "45 oil drums". Line
| item Amt Units Gallium Mass
| 5.70E+01 metric tons Gallium Mass 5.70E+04
| kg Gallium Mass 5.70E+07 grams Liq.
| Gallium Density 6.10E+00 grams/cm3 Gallium Vol
| 9.35E+06 cm3 Oil Drum Volume 5.50E+01
| gallons Vol Ratio 3.79E+03 gallons/cm3
| Oil Drum Volume 2.08E+05 cm3 Gallium Volume
| 4.49E+01 oil drums
|
| ____
|
| [0] https://www.ishtar-collective.net/cards/ghost-fragment-
| darkn...
| auspiv wrote:
| double check that math - olympic pool is 50x25x2 meters, or
| 2500m3. 1 m3 of water is roughly 1 metric ton (1 g/cc = 1 kg/L
| = 1 t/m3) depending on temperature and such.
|
| 57000000g / 5.9 g/cc = 9661017 cc = 9.661m3
| Terr_ wrote:
| Whoops, yeah, made a few mistakes. Next time I'll do the
| usual and open a throwaway spreadsheet. Also, picking
| gallium-density from a slightly higher temperature where it's
| liquid.
| addaon wrote:
| Google is (still) a great tool for this sort of conversion. It
| comes up with just under 58 barrels:
| https://www.google.com/search?q=57+tonnes+%2F+%286.1+g%2Fcm%...
| Terr_ wrote:
| It seems the discrepancy comes Google using 42-gallon
| "petrochemical industry crude oil measuring units" instead of
| 55-gallon "popular physical containers people have probably
| seen before holding all sorts of stuff."
|
| So just reformulate it a bit, put a non-rounded density,
| and...
|
| https://www.google.com/search?q=57+tonnes+%2F+%286.095+g%2Fc.
| ..
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