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DelphiAegis posted:Boy let me tell you about how the first nuclear weapons were designed! They were in fact, a gun where you had two sub-critical masses of Uranium and you fired one into the other and squeezing them together in the right shape made them supercritical and then BOOM! 
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Mar 10, 2021 15:10
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Platystemon posted:
I appreciate that there are a lot of things that are insane about the californium six shooter, but are none of us talking about the 'one complication'? Where, spatially speaking, is that bullet decaying? Just get yourself an extremely leaded holster to prevent your Clint Nukewood balls from being annihilated I guess
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Mar 10, 2021 15:15
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253 has no gamma and mostly beta according to Wikipedia so yeah a lead holster is sufficient
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Mar 10, 2021 15:18
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EvenWorseOpinions posted:I appreciate that there are a lot of things that are insane about the californium six shooter, but are none of us talking about the 'one complication'?
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Mar 10, 2021 15:37
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going to go out on the limb to suggest that maybe a bullet-sized californium bomb would not compress and thus burn very efficiently and god help any metallurgists who try to study the properties of its multiple crystal phases
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Mar 10, 2021 15:42
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Potato Salad posted:going to go out on the limb to suggest that maybe a bullet-sized californium bomb would not compress and thus burn very efficiently Extreme crystal phases are really neat. I don't know much - they're only tangentially related to my field - but then, nobody knows much. That's kind of the point. Prediction of phase changes from first principles is just good enough that we can sometimes guess where to look, and not much use after that. And, of course, the problem with phases that only occur under extreme pressure/temperature conditions or are of short lived materials is that they're very hard to study, because they vanish so quickly. There is a push to look for metastable phases, and I believe even some predicted possibilities, but I don't recall seeing any literature on actual successes yet.
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Mar 10, 2021 15:48
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gonadic io posted:253 has no gamma and mostly beta according to Wikipedia so yeah a lead holster is sufficient That surprises me with it being so heavy, but I know only enough about nuclear physics to know "Yeah okay alright I'll call a professional" CannonFodder posted:The other problem would be dying in the blast equivalent to 10 tons of TNT. The Oklahoma City bombing had a explosion the equivalent of 2.5 tons of TNT. Shooting a bomb 4 times as strong with the range of a pistol is... unwise. That one's simple, you fire it at a 45 degree angle towards the enemy then hop in the refrigerator and close the door. Potato Salad posted:going to go out on the limb to suggest that maybe a bullet-sized californium bomb would not compress and thus burn very efficiently Somewhere, Klapötke's ears started burning
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Mar 10, 2021 15:50
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Jabor posted:Yeah, it'd cost about a billion dollars just for the raw material, and somehow 800 million of that would end up in LockMart's hands. The bullet itself will be the $189 million, the X45-2 Supersonic projectile device with a mini-nuclear warhead and 30 tons of 920 mm steel anti-nuclear plating with infrared, sonar and x-ray vision that will never leave the test phase accounts for the rest Congress will appropriate $6.3 trillion over the next decade for it because the military says it needs this gun to counter China Seth Pecksniff fucked around with this message at 15:59 on Mar 10, 2021 |
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Mar 10, 2021 15:57
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Just need an X-15
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Mar 10, 2021 16:05
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I'm still not hearing anything dumber than actual US projects still in development.
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Mar 10, 2021 16:06
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CannonFodder posted:Wait, Scott Manley is a goon? Always has been
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Mar 10, 2021 16:26
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CannonFodder posted:Wait, Scott Manley is a goon? gently caress yeah he is. Honestly scrolling through his uploads to find the going nuclear series, there is such a diverse nerdy subject set to his videos, it's a wonder he gets anything done at all. And his kids are awesome and adorable whenever he brings them in for a video. 
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Mar 10, 2021 16:27
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By popular demand posted:I'm still not hearing anything dumber than actual US projects still in development. The Californium 253 has to be made in 45 different Congressional Districts even though only 10 currently have the facilities to create it. 35 facilities must first be built. Then it is all shipped to yet another 14 locations to be formed into bullets.
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Mar 10, 2021 16:27
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Ohio's wonderful 4th district is proud to receive 50 billion dollars a year to produce 1 Californium atom.
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Mar 10, 2021 16:31
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CannonFodder posted:The Californium 253 has to be made in 45 different Congressional Districts even though only 10 currently have the facilities to create it. 35 facilities must first be built. Then it is all shipped to yet another 14 locations to be formed into bullets. Each of these facilities will be named the "John/Jane Q. Congressman/woman job and or/money printer go brr facility"
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Mar 10, 2021 16:36
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We interrupt nuclear chat to watch someone’s gran nearly get clocked by a tree https://i.imgur.com/ZdprBrW.gifv
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Mar 10, 2021 17:05
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https://twitter.com/barstoolsports/status/1369517696904224769
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Mar 10, 2021 17:25
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Log082 posted:Extreme crystal phases are really neat. I don't know much - they're only tangentially related to my field - but then, nobody knows much. That's kind of the point. Prediction of phase changes from first principles is just good enough that we can sometimes guess where to look, and not much use after that. And, of course, the problem with phases that only occur under extreme pressure/temperature conditions or are of short lived materials is that they're very hard to study, because they vanish so quickly. There is a push to look for metastable phases, and I believe even some predicted possibilities, but I don't recall seeing any literature on actual successes yet. I've got a thrift-store-find copy of the ANS Plutonium Handbook that goes deep into actinide metallurgy, if you're interested I can post some scans later
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Mar 10, 2021 17:27
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everydayfalls posted:We interrupt nuclear chat to watch someone’s gran nearly get clocked by a tree Shes a lucky lady
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Mar 10, 2021 17:33
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Elviscat posted:That's not how (super)critically is achieved. Make the barrel of an artillery gun out of a neutron absorbing material. A super critical plutonium shell is loaded into the breach. ( it would have to be loaded directly from a sleeve that was also a neutron absorber. When you fire, the slug exits at Mach 2 and starts to go critical when it leaves the barrel. Today's homework question is how far away from the gun will the slug be when it explodes.
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Mar 10, 2021 17:34
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Since both the Davy Crockett and the equivalent Russian nuclear artillery shells are a complete device rather than a core I'm guessing the answer is TOO CLOSE.
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Mar 10, 2021 17:38
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WorldsStongestNerd posted:
Not far at all. Nuclear reactions happen incredibly quickly, a nuclear bomb's detonation is complete in a few tens of nanoseconds. Even with a hypersonic muzzle velocity that thing's not even getting an inch downrange before it's done.
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Mar 10, 2021 17:41
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Jet Jaguar posted:I forget, WHY did somebody feel the need to stage this, what could have been one of the last things they ever saw? Welcome to the portion of DOE run by the DOD: They have much looser standards and safety protocols than the Civilian run NRC oversighted DOE sites, and that's saying something. It got to the point that Safety Officers were resigning en masse because Contractors REFUSED to follow safety protocols and implement changes to improve safety. The DOD portion of the DOE labs gets away with a lot of really sketchy poo poo in handling Weapons Grade plutonium. CommieGIR fucked around with this message at 17:46 on Mar 10, 2021 |
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Mar 10, 2021 17:42
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Attempting to transport a big ol' piece of glass in an elevator https://i.imgur.com/QwsbOPU.mp4
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Mar 10, 2021 17:47
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Hollywood says reactors are “critical” like it’s a bad thing, when it’s actually the steady operating state. The scary scenario is going “prompt supercritical”, and that just sounds cooler.
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Mar 10, 2021 17:54
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Platystemon posted:Hollywood says reactors are “critical” like it’s a bad thing, when it’s actually the steady operating state. Yeah, its pretty annoying. I do Nuclear energy and science outreach and that's one of the questions kids pop a lot.
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Mar 10, 2021 18:02
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Platystemon posted:Hollywood says reactors are “critical” like it’s a bad thing, when it’s actually the steady operating state. And if you can't make your reactor go supercritical then you could never increase power. quote:The scary scenario is going “prompt supercritical”, and that just sounds cooler. Scary awesome.
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Mar 10, 2021 18:20
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Is prompt supercritical similar in its intent to the phrase 'rapid unplanned disassembly' or 'rapod-ox event'?
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Mar 10, 2021 18:38
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Platystemon posted:Hollywood says reactors are “critical” like it’s a bad thing, when it’s actually the steady operating state. I mean, not to give Hollywood too much credit, but "critical" outside of a reactor does tend to be a big fuckin deal, and I imagine that makes it easy enough to take as the technobabble word for "radioactive problem" if you're not versed in how a reactor operates. e: kinda like how gasoline vapor deflagrations inside the piston in an IC engine are fine and cool, but when they happen on the pavement at the gas pump it's An Issue Phy fucked around with this message at 18:43 on Mar 10, 2021 |
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Mar 10, 2021 18:40
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Samuel L. Hacksaw posted:Is prompt supercritical similar in its intent to the phrase 'rapid unplanned disassembly' or 'rapod-ox event'? It can be, depending on if you can damper it fast enough. Or it dampers itself like SL-1 through RUD.... Phy posted:I mean, not to give Hollywood too much credit, but "critical" outside of a reactor does tend to be a big fuckin deal, and I imagine that makes it easy enough to take as the technobabble word for "radioactive problem" if you're not versed in how a reactor operates. Critical would be a stable configuration where you are neither adding or subtracting from your total neutrons in your reaction. Supercritical would be the bad one outside of a reactor, as that means overall reactivity is increasing and neutron count is accelerating. Subcritical is neutron population is decreasing. CommieGIR fucked around with this message at 18:59 on Mar 10, 2021 |
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Mar 10, 2021 18:44
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shame on an IGA posted:I've got a thrift-store-find copy of the ANS Plutonium Handbook that goes deep into actinide metallurgy, if you're interested I can post some scans later Oh hell yes.
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Mar 10, 2021 18:45
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Samuel L. Hacksaw posted:Is prompt supercritical similar in its intent to the phrase 'rapid unplanned disassembly' or 'rapod-ox event'? When a big atom fissions, it releases some neutrons and some radioactive daughter elements. Those radioactive daughter elements have their own half-lives and will themselves decay. Some of them are long-lived and become the elements you're concerned about if your reactor blows up. Some of them are much longer-lived than that and become the elements you're concerned about when it's time to dispose of your fuel rods. Some of them are much shorter-lived and have half-lives on the order of milliseconds or minutes, and when they decay they release their own additional neutrons. The neutrons released directly when the uranium or plutonium or whatever fissions are called prompt neutrons. They show up very rapidly, and are called prompt neutrons. The neutrons emitted by the rapid decays of the daughters show up milliseconds to minutes later, and are called delayed neutrons. It is that phenomenon that makes control of a fission reactor possible, it's what gives your control loop time to work: you arrange things so that if you consider only the prompt neutrons, then your reactor geometry is subcritical, and will die off. But then when the delayed neutrons show up, the additional reactivity they bring kicks your reaction rate up. All "critical" means is that your reaction is proceeding at steady-state: it is neither increasing in power or decreasing in power. Subcritical means the rate is declining, supercritical means it's increasing. So bringing your reactor supercritical is part of the normal operating regime: you need to do this to increase power at all. But "prompt supercritical" means that it is supercritical based only off of the prompt neutrons, and even more reactivity is just milliseconds away, and means you've probably got a biiiig positive feedback loop underway and things are blowing up right now. So in other words yes.
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Mar 10, 2021 18:56
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I want to be the manager of soothing words for uncomfortable events.
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Mar 10, 2021 19:01
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Samuel L. Hacksaw posted:Is prompt supercritical similar in its intent to the phrase 'rapid unplanned disassembly' or 'rapod-ox event'? No. It’s all technical. The critical point is the balance point of fission events. When the reactor is supercritical, each nucleus that splits will go on to cause the splitting of, on average, more than one nucleus elsewhere in the fuel. The reaction increases in intensity. When the reactor is subcritical, each split nucleus causes an average of less than one to split elsewhere. The reaction declines. A critical reactor is at balance, with activity that sustains itself and neither increases or decreases in intensity. The “prompt” in “prompt supercritcal” refers to “prompt neutrons”. These are emitted from a split atom almost instantly. If, on average, one of these prompt neutrons triggers the release of more than prompt neutron elsewhere, exponential growth takes you from a single split to “all your fuel split” in moments. This is what happens in atomic bombs. The way to go supercritical (throttle up the reactor) in a controlled fashion is with delayed neutrons. Now there’s some real time between the steps of exponential growth and it is gradual enough to be arrested by other forces (ideally passively) at a reaction rate that can be sustained by the reactor’s construction, not destroy it. Platystemon fucked around with this message at 19:07 on Mar 10, 2021 |
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Mar 10, 2021 19:04
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Its worth noting Prompt Criticality can happen in Reactors (as it did in SL-1) but its neither desired nor encouraged. https://en.wikipedia.org/wiki/Criticality_accident#Known_incidents
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Mar 10, 2021 19:16
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CommieGIR posted:It can be, depending on if you can damper it fast enough. Or it dampers itself like SL-1 through RUD.... Ok, but am I correct that if "critical" means "a self-sustaining fission reaction where the number of neutrons pinging about the fissile material is neither increasing nor decreasing", you still don't want to be standing next to it if it's unshielded and uncontrolled?
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Mar 10, 2021 19:20
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Phy posted:Ok, but am I correct that if "critical" means "a self-sustaining fission reaction where the number of neutrons pinging about the fissile material is neither increasing nor decreasing", you still don't want to be standing next to it if it's unshielded and uncontrolled? Yes, but usually in films they refer to it "going critical" which would mean its operating at a stable state when really they mean, usually that its going supercritical and running away in an excursion event. Its really one of those scientific terms that's been abused so often that people just use it the wrong way and everybody understands what they mean.
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Mar 10, 2021 19:25
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Prompt critical is sort of like the nuclear equivalent of diesel runaway- the reactor has found its way into a positive feedback loop based only on things that humans cannot take away from it. So it will increase its output until some component exceeds its tolerance or some resource is fully consumed. Of course when a diesel engine rips itself apart it doesn't poison the surrounding area for decades.
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Mar 10, 2021 19:27
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haveblue posted:Prompt critical is sort of like the nuclear equivalent of diesel runaway- the reactor has found its way into a positive feedback loop based only on things that humans cannot take away from it. So it will increase its output until some component exceeds its tolerance or some resource is fully consumed. Of course when a diesel engine rips itself apart it doesn't poison the surrounding area for decades.
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Mar 10, 2021 19:30
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Writing "superdupercritical" into my next post-apocalyptic novel
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Mar 10, 2021 19:30
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