Chapter 83 Chapter 83

Although it's still early morning in Kansas, Robert Puller's voice doesn't sound very sleepy.Puller didn't think his brother would get much sleep in a U.S. corrections camp.My brother is a talented person.Outside prison, talented people don't get much sleep because the world demands so much of their time and intelligence.Puller estimated that such a person, locked in a cell with three concrete walls and an iron door on one side for twenty-three of the twenty-four hours a day, would likewise not sleep much. "How are you, brother?" asked Robert. "Better and worse."

"It's nice to have balance in your life." "92 and 94. What do these numbers mean to you?" "They're all even numbers." "Look at it from another angle." "Give me some background." His brother sounded a little involved, and it was more than just ordinary curiosity. "From a purely scientific standpoint. Your area of ​​expertise." The hour hand jumped for two seconds. "92 is the atomic number of uranium and 94 is the atomic number of plutonium." "I remember that too." "Why do you ask about this?"

"A guess." "Tell me." "How much uranium and plutonium are needed to make a nuclear weapon?" "what?" "answer the questions." "What are you involved in, John?" My brother doesn't call him John very often.His usual address for his younger brothers was "Little Brother," and sometimes "Little John"—the latter being less used in recent years because it reminded them of their father, John Puller, Sr. "Don't ask for now. Give me the clearest explanation." "It takes a lot of materials to make a nuclear weapon. Most of it you can get your hands on. There are some other things you can make too, and it's not that hard if you have enough time and some experts. The hardest thing to get is the ability to Fission nuclear fuel, there are only two types of fission nuclear fuel."

"Uranium and plutonium." "Right. And you need to have highly enriched uranium, uranium-235 or something, to make a bomb. You also need to make equipment, and it takes a lot of money and a lot of scientists, plus it takes a few years." "What about plutonium?" "Do we have to talk about this? They're on the phone." "Nobody's listening, Bobby," Puller said. "I've made arrangements for our conversation to be private." His brother didn't speak for a long time, and then he said: "In my opinion, no matter what kind of thing you are involved in, you are no longer just guessing."

"What about plutonium?" "Plutonium-239 is formed in breeder reactors by crashing radioactive uranium. The key is to get rid of plutonium-240. Reactor-grade plutonium contains a lot of plutonium-240, which is an impurity of plutonium. The higher the content, the plutonium The less likely it is to be used as fuel for nuclear weapons." "Is plutonium hard to come by, too?" "No one on the street can get it. Who's going to have a breeder reactor in their backyard?" "But someone can still get it?" "I think you could steal it, or buy it on the black market."

"What about in America? How do we make this stuff?" "The only plant in the United States that uses the gas diffusion method to separate enriched uranium is in Paducah, Kentucky. But what is enriched there is uranium for nuclear reactors, and the process is completely different." "But according to their processing methods, can they also process highly enriched uranium? The kind of nuclear fuel used to make nuclear weapons?" "Paducah produces low-enriched uranium for nuclear power generation, not weapons-grade highly-enriched uranium for nuclear bomb fuel."

"But plants like Paducah can still produce highly enriched uranium?" Puller insisted. "Theoretically, yes." Robert asked after a moment's pause, "What are you asking about?" "How much uranium-235 is needed to produce a nuclear bomb?" "Depends on what type of bomb and what method of making it." "A rough estimate?" Puller asked. "A nuclear bomb with a simple structure and the explosive equivalent of Nagasaki, Japan, needs 15 kg to 50 kg of highly enriched uranium or 6 kg to 9 kg of plutonium. If your weapon manufacturing process is very advanced, the bomb The design is very reasonable, and you can achieve the same explosive effect with about 9 kilograms of highly enriched uranium or at least 2 kilograms of plutonium."

"What was the power of the atomic bomb in Nagasaki?" "The explosive yield is roughly equivalent to 21,000 tons of explosives, with the fallout fallout. Twenty million kilograms of TNT. A weapon of mass destruction." "What about using a little more highly enriched uranium or plutonium?" "The explosive effect is multiplied. But it also depends on how the bomb is designed. You can use a gun detonation method, which is not good, and the first atomic bomb dropped on Hiroshima, Japan was designed using this principle. This method of detonation requires a long tube, like the barrel of a gun. You put half of the nuclear charge on one end, which is backed by conventional explosives, and the other half of the nuclear charge is placed on the other end. Conventional explosives detonate Finally, push half of the nuclear charge along the 'barrel' to hit the other half of the nuclear charge, and then a series of chain reactions will occur. This method is very primitive, the utilization rate of nuclear fuel is low, and the explosive yield is greatly limited .You need a very, very long 'barrel' to ensure the chain reaction effect after the impact, and you can only use uranium, not plutonium, because the plutonium has too many impurities. So, later on, the atomic bombs were made of Implosion."

"Tell me about implosion," Puller said. "You can use uranium or plutonium. You need to use a large amount of conventional explosives and make a layer called an explosive lens. The explosive detonates inwards, compressing the nuclear fuel in the inner sphere to supercritical state. The detonation wave needs to be formed into a spherical shape. , uniformly compress the uranium or plutonium distributed at each point. Otherwise, the instability of the interface will occur, making the nuclear charge inside out of its original position, fission cannot be achieved, and your nuclear bomb will be ruined. You also There must be an explosive detonator, a metal projectile with a high density and a neutron source for nuclear ignition, and an ideal neutron reflector to reflect the escaped neutrons back. The trick here is that the The time for neutron ignition and bombardment of uranium or plutonium should not be too early, and it must be controlled until the nuclear charge achieves the most ideal supercritical mass. The longer the fissile material maintains the chain reaction process, the more atomic nuclei will split, and the power of the nuclear bomb will increase. It's bigger. If your design is top-notch, you can get three times the explosive yield without adding a single gram of nuclear fuel."

"Is there anything else you need?" "What do you mean exactly?" "Can you tell me about gold leaf and tungsten carbide?" There was a few seconds of silence.Then Robert asked: "Why do you mention these two things in particular? Are they present in the case you are working on?" "yes." "My God." "Tell me, Bobby. My time is running out." "Gold foil can be used on the device that produces neutrons, that is, the neutron source. It is a small spherical thing, and the outer layer is coated with beryllium and polonium, and the gold foil is used as an isolation layer between these two things. This small The ball is at the center of the bomb, and of course it is the most critical place in the design and manufacture process."

"What about tungsten carbide?" "It's three times harder than steel, and it's also very dense. It's an ideal material for the neutron reflector. Its function is to reflect the escaped neutrons back to achieve the maximum supercritical state. Are you telling me... ...where are you now?" "In the U.S." "How did they get nuclear fuel?" "In the 1960s, the government built a secret engineering facility. It's long since closed down, but the building with its one-meter-thick concrete walls is still here. What do you hear when I say this ?All the workers who work here are brought in from outside, and they live in a residential area next to the building. These people are absolutely not allowed to talk about their work with the local people. When the facility is closed, they They were all transported away together. I wonder if you've heard of it in some way? You were very close to the people who did it when you were in the Air Force." "A one-meter-thick concrete wall?" "Dome-shaped." "In the middle of nowhere?" "In the country, almost out of the way. The total population here is much smaller than a block in Brooklyn. The facility then had its own fire station, where I found a paper that read 92 and 94. At the same time, I also saw their regulations that companies that mine coal in the open pit are not allowed to conduct blasting operations within a few kilometers of it.” "Exploding in that area? Are you serious?" "yes." "It's unbelievable. Even if you blast it a few kilometers away, it will loosen the cracks that already exist in the underground rock bed. It will cause a lot of disaster." "What the hell is that facility for?" "I don't know. I wasn't even born in the 1960s." "But what if I asked you to guess? Based on your experience." His brother let out a long sigh. "I would never have told you this if I was still in uniform." He paused. "Speaking out I could very well be accused of treason. But since I've been convicted of treason, so be it!" He paused again. "I've heard before that our country built some factories in remote places to refine and enrich nuclear fuel. This was all after World War II, when the only thing that mattered was how to defeat the Soviet Union. The purpose of building these factories was Get highly enriched uranium, and of course plutonium, and use it to make nuclear weapons. Later, most, if not all, of these plants were closed." "why?" "The technology wasn't stable enough, or it cost too much money. It was a new scientific field at the time, and people were figuring it out with all kinds of trials and all kinds of errors. The main face was mistakes." "Well, they're all closed. Once closed they move everything, don't they?" His brother didn't answer. "Bobby? Isn't it?" "If you took all the 'stuff' out, would you still cover it with a one-meter-thick concrete dome?" "Has anyone criticized and complained about the construction of this facility? Didn't the residents of the project site protest? No one in the government objected?" "You have to put in context, John. In the 1960s, the Soviet Union was our biggest and most dangerous enemy. There was no round-the-clock, rolling news in those days. People genuinely believed in their government , although the subsequent Vietnam War and Watergate changed their views. Since nothing special happened for quite a period of time, I guess the local people thought everything was normal." He paused and asked : "Is that facility just left open in the local area?" "It doesn't have any open spaces. Even the concrete walls are almost completely covered by forest plants." "What do you think is going to happen?" "It's the kind of thing you're probably thinking is going to happen." "You need to report to your superiors immediately." "I'm going to report, but there's one thing." "what?" "I'm not sure our people can be trusted." "Is there anyone there you can trust?" "Yes. But I want to ask you to do me one more favor." "I help you? I'm in jail, John." "It's okay. You can still help me there. CID will be my back, and they can make some workarounds to your situation over there. I really need you, Bobby." His brother replied without hesitation: "Whatever you need me to do, just say it."