4 ms·

Worth noting that with "disable" here they mean "trigger an immediate explosion with ~3% of their actual yield". That can still be a lot, expose radioactivity,

by xg15 3y ago

Worth noting that with "disable" here they mean "trigger an immediate explosion with ~3% of their actual yield". That can still be a lot, expose radioactivity, etc: > When the neutrino beam hits a bomb, it will cause the fizzle explosion with 3% of the full strength. It seems that it is not possible to decrease the magnitude of the explosion smaller than this number at this stage. It is important to decrease this number to destroy bombs safely. We are not sure what this means when the plutonium or uranium is used to ignite the hydrogen bomb. We may just break the bomb or may lead to a full explosion. If such a tech existed, it could give a new edge to MAD though, because just storing nuclear bombs would suddenly carry a risk of "spontaneous" nuclear explosions. This might already be enough to have a chilling effect. (Then again, it might not...)

perlgeek 3y ago
It would boost the navy's ego dramatically, because then nukes carried on submarines would have another strategic edge over silo-based missiles.
- Someone 3y ago
  I bet the Air Force would ask for loads and loads more money so that they could resurrect the MX “racetrack” concept. https://www.airandspaceforces.com/article/peacekeeper-by-fits-and-starts/ https://www.airandspaceforces.com/article/peacekeeper-by-fit...: “In 1979, Carter acknowledged that fixed-based missiles were “becoming vulnerable to attack” and authorized full-scale development of MX to be deployed in Multiple Protective Shelters, a “shell-game” arrangement in the deserts of Nevada and Utah. It provided for 200 “racetracks” or long oval roadways. Each of them was a 15-mile closed loop with 23 spur roads leading off of it to concrete and steel shelters. One MX would be assigned to each racetrack, able to take cover in any of the 23 shelters. For arms control verification, the shelters would have a removable “plug” in the roof, to be opened at specific intervals to allow the Soviets to see that there was only one MX per racetrack. “The system consists of a missile, a transporter or fancy truck, a shelter or concrete bunker, a launcher decoy, and some cheap roads,” said Deputy Undersecretary of Defense Seymour Zeiberg. “For security reasons, a two-and-one-half-acre plot around the shelters will be fenced off. … The fenced area is the same as we use in the Minuteman bases. We expect that farming and grazing can be right up to the fence. … The roads connecting the shelters will be as simple as we can get away with.” The footprint of the project was significantly greater than that, said local ranchers and farmers who were opposed to it. True, the total “public exclusion zone” was 33 square miles, but the clusters were not bunched together into a single space. The total deployment area took in about 15,000 square miles, some of which might be closed off in times of increased security. That, along with more than 10,000 miles of connecting and service roads, would change the character of the desert region. Furthermore, the project would use large amounts of water, especially during construction, and deplete scarce ground water reserves. The governors of Nevada and Utah did not want the missiles in their states.“
mikeyouse 3y ago
I wonder what that means for our "dial-a-yield" designs.. The B61 can be adjusted to 0.3KT, 1.5KT, 10KT, or 50KT. Is the 3% yield on the smallest possible setting or the largest? Some of them used to be 10kt or 350kt -- 3% could still be a massive explosion if applied to the latter.
- blibble 3y ago
  presumably the lowest as an exact sequence of events and states need to be present for the higher yields (e.g. gas for boosting needs to have been generated)
- the8472 3y ago
  Presumably those calculations are just based on the critical mass of fissile material, not based on design yield which would include a fusion-boost.
  - denton-scratch 3y ago
    I think that to get the fusion boost, you need a highly-symmetric implosion, which isn't what you'd get by just toasting the TNT. Their 3% figure is presumably what they think you'd achieve by the bomb just "cooking off".
    - the8472 3y ago
      That's... what I wrote?
fpgaminer 3y ago
Yeah, seems like the downsides are: * 3% explosive yield * Likely a dirty explosion, spreading radioactive contaminants. * The area where the beam is targeted (couple meter radius) gets a 1 Sv/sec dose, for about 100 seconds. "compared with the U.S. Federal off-site limit of 1 mSV/year" I'm also curious if anything inside the earth gets dosed by the beam? I don't know enough about neutrinos to speculate. Also, wouldn't one assume that these bombs have neutron shields on them, to prevent accidental triggering by the stray neutron source? Hence, they'd really need the beam to target _inside_ the bomb, not just near it. Finally, skimming the paper, I didn't see mention of the energy levels of the neutrons they expect to hit the radioactive materials. Most radioactive isotopes don't have a large cross section for fast neutrons. Is it expected for this hadron shower to generate thermal neutrons? Otherwise, the beam would need to be several orders of magnitude stronger... (Not that the idea isn't cool as fuck) EDIT: Thinking about it a bit. If I understand the paper correctly, the beam has to be at 1000TeV to penetrate the Earth and hit the target, so you can't decrease the beam's strength and mitigate the above issues. But if the beam could be PWM'd, then you can effectively do that. And if you can lower the effective energy of the beam, then it might be possible to spray a slow and steady stream of neutrons inside the bomb, slowly decaying all the radioactive isotopes. It would take a lot longer, on the order of months, and would probably be detectable, but at least there wouldn't be that pesky issue of turning it into a small dirty bomb...
otikik 3y ago
Hm. Do neutrino beams occur naturally in the universe? From my almost illiterate level: It seems like a supernova will produce a bunch of neutrinos in one go. And they are affected by gravity. So a black hole near with a supernova could act as a gravity lens and "focus" the neutrinos. Does this mean that any nuclear bomb has a (infinitesimal) chance of exploding with 3% of their actual yield, apparently on their own?
- itishappy 3y ago
  Sounds plausible, but likely to be somewhat far down our list of existential problems if a nearby star goes supernova.
  - otikik 3y ago
    It might not need to be near, if the black hole is powerful enough

by xg15 3y ago

perlgeek 3y ago

It would boost the navy's ego dramatically, because then nukes carried on submarines would have another strategic edge over silo-based missiles.

Someone 3y ago
I bet the Air Force would ask for loads and loads more money so that they could resurrect the MX “racetrack” concept. https://www.airandspaceforces.com/article/peacekeeper-by-fits-and-starts/ https://www.airandspaceforces.com/article/peacekeeper-by-fit...: “In 1979, Carter acknowledged that fixed-based missiles were “becoming vulnerable to attack” and authorized full-scale development of MX to be deployed in Multiple Protective Shelters, a “shell-game” arrangement in the deserts of Nevada and Utah. It provided for 200 “racetracks” or long oval roadways. Each of them was a 15-mile closed loop with 23 spur roads leading off of it to concrete and steel shelters. One MX would be assigned to each racetrack, able to take cover in any of the 23 shelters. For arms control verification, the shelters would have a removable “plug” in the roof, to be opened at specific intervals to allow the Soviets to see that there was only one MX per racetrack. “The system consists of a missile, a transporter or fancy truck, a shelter or concrete bunker, a launcher decoy, and some cheap roads,” said Deputy Undersecretary of Defense Seymour Zeiberg. “For security reasons, a two-and-one-half-acre plot around the shelters will be fenced off. … The fenced area is the same as we use in the Minuteman bases. We expect that farming and grazing can be right up to the fence. … The roads connecting the shelters will be as simple as we can get away with.” The footprint of the project was significantly greater than that, said local ranchers and farmers who were opposed to it. True, the total “public exclusion zone” was 33 square miles, but the clusters were not bunched together into a single space. The total deployment area took in about 15,000 square miles, some of which might be closed off in times of increased security. That, along with more than 10,000 miles of connecting and service roads, would change the character of the desert region. Furthermore, the project would use large amounts of water, especially during construction, and deplete scarce ground water reserves. The governors of Nevada and Utah did not want the missiles in their states.“

mikeyouse 3y ago

I wonder what that means for our "dial-a-yield" designs.. The B61 can be adjusted to 0.3KT, 1.5KT, 10KT, or 50KT. Is the 3% yield on the smallest possible setting or the largest? Some of them used to be 10kt or 350kt -- 3% could still be a massive explosion if applied to the latter.

blibble 3y ago
presumably the lowest as an exact sequence of events and states need to be present for the higher yields (e.g. gas for boosting needs to have been generated)
the8472 3y ago
Presumably those calculations are just based on the critical mass of fissile material, not based on design yield which would include a fusion-boost.
- denton-scratch 3y ago
  I think that to get the fusion boost, you need a highly-symmetric implosion, which isn't what you'd get by just toasting the TNT. Their 3% figure is presumably what they think you'd achieve by the bomb just "cooking off".
  - the8472 3y ago
    That's... what I wrote?

fpgaminer 3y ago

Yeah, seems like the downsides are: * 3% explosive yield * Likely a dirty explosion, spreading radioactive contaminants. * The area where the beam is targeted (couple meter radius) gets a 1 Sv/sec dose, for about 100 seconds. "compared with the U.S. Federal off-site limit of 1 mSV/year" I'm also curious if anything inside the earth gets dosed by the beam? I don't know enough about neutrinos to speculate. Also, wouldn't one assume that these bombs have neutron shields on them, to prevent accidental triggering by the stray neutron source? Hence, they'd really need the beam to target _inside_ the bomb, not just near it. Finally, skimming the paper, I didn't see mention of the energy levels of the neutrons they expect to hit the radioactive materials. Most radioactive isotopes don't have a large cross section for fast neutrons. Is it expected for this hadron shower to generate thermal neutrons? Otherwise, the beam would need to be several orders of magnitude stronger... (Not that the idea isn't cool as fuck) EDIT: Thinking about it a bit. If I understand the paper correctly, the beam has to be at 1000TeV to penetrate the Earth and hit the target, so you can't decrease the beam's strength and mitigate the above issues. But if the beam could be PWM'd, then you can effectively do that. And if you can lower the effective energy of the beam, then it might be possible to spray a slow and steady stream of neutrons inside the bomb, slowly decaying all the radioactive isotopes. It would take a lot longer, on the order of months, and would probably be detectable, but at least there wouldn't be that pesky issue of turning it into a small dirty bomb...

otikik 3y ago

Hm. Do neutrino beams occur naturally in the universe? From my almost illiterate level: It seems like a supernova will produce a bunch of neutrinos in one go. And they are affected by gravity. So a black hole near with a supernova could act as a gravity lens and "focus" the neutrinos. Does this mean that any nuclear bomb has a (infinitesimal) chance of exploding with 3% of their actual yield, apparently on their own?

itishappy 3y ago
Sounds plausible, but likely to be somewhat far down our list of existential problems if a nearby star goes supernova.
- otikik 3y ago
  It might not need to be near, if the black hole is powerful enough