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What could explain the gallium anomaly?

quantamagazine.org

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Re: What could explain the gallium anomaly?

#21

Post by sterlind »

Etheryte wrote: post #11
dylan604 wrote: post #6

Earlier quoted context omitted.

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.

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.

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.

Re: What could explain the gallium anomaly?

#22

Post by sterlind »

CamperBob2 wrote: post #2

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.

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.

Re: What could explain the gallium anomaly?

#23

Post by CamperBob2 »

sterlind wrote: post #22
CamperBob2 wrote: post #2

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.

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.

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.

Re: What could explain the gallium anomaly?

#24

Post by eigenket »

AnimalMuppet wrote: post #17
torrefatto wrote: post #13

Earlier quoted context omitted.

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.

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 du…

> 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.

Re: What could explain the gallium anomaly?

#25

Post by mypalmike »

sterlind wrote: post #21
Etheryte wrote: post #11

Earlier quoted context omitted.

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.

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.

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...

Re: What could explain the gallium anomaly?

#26

Post by floxy »

AnimalMuppet wrote: post #17
torrefatto wrote: post #13

Earlier quoted context omitted.

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.

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 du…

>gallium->germanium should emit a neutrino, not absorb one.

Neutron-Neutrino interaction?

https://www.vivaxsolutions.com/physics/feynman-diagrams.aspx

Re: What could explain the gallium anomaly?

#27

Post by dudinax »

CamperBob2 wrote: post #23
sterlind wrote: post #22

Earlier quoted context omitted.

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.

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.

Maybe the fish get less shielding.

Re: What could explain the gallium anomaly?

#28

Post by postalrat »

CamperBob2 wrote: post #23
sterlind wrote: post #22

Earlier quoted context omitted.

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.

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.

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.

Re: What could explain the gallium anomaly?

#30

Post by jessriedel »

Terr_ wrote: post #4

> 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 gravi…

>> 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.

To be clear, physicists have been thinking very non-fictionally about sterile neutrinos since 1968.

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