Incoming links: Uranium
These must have been gamma rays.
Just before he left Cambridge for Montreal in 1898, Rutherford conducted a simple, systematic experiment to study the absorption of rays from uranium. [...] In 1901 he determined that Becquerel's rays are indeed electromagnetic rays. He called them γ (gamma) rays.
This terminology is used e.g. in Marie Curie's Polonium paper:
Some minerals containing uranium and thorium (pitchblende, chalcolite, uranite) are very active from the point of view of the emission of Becquerel rays.
Uranium emits them, you can see their mass to charge ratio under magnetic field and so deduce that they are electrons.
Caused by weak interaction TODO why/how.
The emitted electron kinetic energy is random from zero to a maximum value. The rest goes into a neutrino. This is how the neutrino was first discovered/observed indirectly. This is well illustrated in a decay scheme such as Figure "caesium-137 decay scheme".
This was the first full scale nuclear reactor in the world, and was brought up slowly to test it out.
Hanford B Reactor tour by Studio McGraw
. Source. 2016.- youtu.be/8rlVHEY7BF0?t=335 good description of the fuel element. It uses uranium metal, not Uranium dioxide
- youtu.be/8rlVHEY7BF0?t=652 N Reactor and F Reactor were identical, and came up 2 months later, but much faster because of what they learned on the B
Highly radioactive isotope of caesium with half-life of 30.17 y. Produced from the nuclear fission of uranium, TODO exact reaction, not found in nature.
The fucked thing about this byproduct is that it is in the same chemical family as sodium, and therefore forms a salt that looks like regular table salt, and dissolves in water and therefore easily enters your body and sticks to things.
Another problem is that its half-life is long enough that it doesn't lose radioactivity very quickly compared to the life of a human person, although it is short enough to make it highly toxic, making it a terrible pollutant when released.
This is why for example in the goiânia accident a girl ended up ingesting Caesium-137 after eating an egg after touching the Caesium with her hands.
caesium-137 decay scheme
. Source. The first human-made nuclear chain reaction.
- youtu.be/mnScq24BEmc?t=114 the main cost for the reactor was the graphite. Presumably they already had the uranium in hand?. Edit, no, it is because it was a specialized graphite: Video 2. "German graphite from The Genius Behind the Bomb (1992)", i.e. nuclear graphite.
"Joachimsthal" is the German for it. Note how it is just near the modern frontier between Germany and the Czech Republic.
en.wikipedia.org/w/index.php?title=Uranium&oldid=1243907294#Pre-discovery_use:
In the early 19th century, the world's only known sources of uranium ore were these mines.
Apparently the region was a silver mining center:
Starting in the late Middle Ages, pitchblende was extracted from the Habsburg silver mines in Joachimsthal, Bohemia (now Jáchymov in the Czech Republic), and was used as a coloring agent in the local glassmaking industry
Uranium-based, dropped on Hiroshima. The uranium was enriched at the Clinton Engineer Works.
The lab that made Chicago Pile-1, located in the University of Chicago. Metallurgical in this context basically as in "working with the metals uranium and plutonium".
Given their experience, they also designed the important X-10 Graphite Reactor and the B Reactor which were built in other locations.
A weapons-grade ring of electrorefined plutonium, typical of the rings refined at Los Alamos and sent to Rocky Flats for fabrication
. Source. The ring has a purity of 99.96%, weighs 5.3 kg, and is approx 11 cm in diameter. It is enough plutonium for one bomb core. Which city shall we blow up today?Ciro Santilli is mildly obsessed by nuclear reactions, because they are so quirky. How can a little ball destroy a city? How can putting too much of it together produce criticality and kill people like in the Slotin accident or the Tokaimura criticality accident. It is mind blowing really.
More fun nuclear stuff to watch:
- Dr. Strangelove (1964)
- en.wikipedia.org/wiki/Chernobyl_(miniseries)
- The World Of Enrico Fermi by Harvard Project Physics (1970)
- Fat Man and Little Boy (1987) shows a possibly reasonably realistic of the history of the development of the Trinity
The Ultimate Guide to Nuclear Weapons by hypohystericalhistory (2022)
Source. Good overall summary. Some interesting points:- youtu.be/8uIPQBOCJ64?t=2946 talks about the difference between tactical and strategic nuclear weapons
- youtu.be/8uIPQBOCJ64?t=3291 mentions variable yield devices, this is the main new thing Ciro Santilli learned from this video
- youtu.be/8uIPQBOCJ64?t=3416 discusses if a strategic nuclear weapon usage would inevitably lead to tactical nuclear weapon escalation. It then mentions one case in which a possibly comparable escalation didn't happen: the abstinence of using chemical weapon during World War II.
This is the papaer where Marie Curie announced the discovery of Polonium.
Here's a link with OCR on the French Wikisource: fr.wikisource.org/wiki/%C5%92uvres_de_Pierre_Curie/23. It's from a 1908 collection of works, but it is the exact same paper.
Here's an English translation: web.lemoyne.edu/~giunta/curiespo.html
First a recap of previous work:Note the cute terminology "Becquerel rays", which were only later understood to be electromagnetic radiation now known as gamma rays.
Some minerals containing uranium and thorium (pitchblende, chalcolite, uranite) are very active from the point of view of the emission of Becquerel rays. In a previous work, one of us showed that their activity is even greater than that of uranium and thorium, and expressed the opinion that this effect was due to some other very active substance contained in small quantities in these minerals.
Then some more recapitulation of the previously discussed groundbreaking idea that only atom counts matter for radioactivity, regardless of their chemical configuration as in fluorescence:
The study of compounds of uranium and thorium had shown, in fact, that the property of emitting rays which make air conductive and which act on photographic plates is a specific property of uranium and thorium which is found in all compounds of these metals, all the more weakened as the proportion of active metal in the compound is itself lower. The physical state of the substances seems to have a completely secondary importance. Various experiments have shown that the state of mixture of the substances seems to act only by varying the proportion of active bodies and the absorption produced by the inert substances. Certain causes (such as the presence of impurities) which act so powerfully on phosphorescence or fluorescence are therefore here completely without action. It therefore becomes very probable that if certain minerals are more active than uranium and thorium, it is because they contain a substance more active than these metals.
Then the key innovation: they used radioactivity measures to guide their purification work:
We have sought to isolate this substance in pitchblende, and experience has confirmed the above predictions.Our chemical research has been constantly guided by the control of the radiant activity of the products separated at each operation. Each product is placed on one of the plates of a condenser, and the conductivity acquired by the air is measured using an electrometer and a piezoelectric quartz, as in the work cited above. We thus have not only an indication but a number which accounts for the richness of the product in active substance.
Next they describe in high level their separation process, and I can't understand anything. But that's OK
Finally towards the end, bombs are dropped:
- the new elemnt is next to bismuth. If you stop now and look at a periodic table, you will see that bismuth is exactly one element before polonium
- "simple bodies" is their cute terminology for atoms, whose existence at the time not yet full aknowledged Section "History of the atomic theory"
- we call it polonium
By carrying out these various operations, we obtain increasingly active products. Finally, we obtained a substance whose activity is about 400 times greater than that of uranium.We have sought, among the bodies currently known, to see if there are any active ones. We have examined compounds of almost all simple bodies; thanks to the great kindness of several chemists, we have had samples of the rarest substances. Uranium and thorium are the only ones clearly active, tantalum is perhaps very weakly so.We therefore believe that the substance that we have removed from the pitchblende contains a metal not yet reported, close to bismuth by its analytical properties. If the existence of this new metal is confirmed, we propose to call it polonium, from the name of the country of origin of one of us.
They managed to purify it enough to look at the emission spectrum and it seems novel:
Mr. Demarçay was kind enough to examine the spectrum of the body that we are studying. He was unable to distinguish any characteristic line apart from those due to impurities. This fact does not support the idea of the existence of a new metal. However, Mr. Demarçay pointed out to us that uranium, thorium and tantalum offer particular spectra, formed of innumerable lines, very fine, difficult to perceive.
And once again, our radiation-based analytical chemistry technique is new:
Allow us to note that if the existence of a new element is confirmed, this discovery will be uniquely attributable to the new method of detection that Becquerel rays provide.
What a material:
- only exists in trace amounts in nature,but it can be produced at kilogram scale in breeder reactors
- it is only intentionally produced for one application, and one application only basically: nuclear weapons
Burning and Extinguishing Characteristics of Plutonium Metal Fires by RobPlonski
. Source. Commented by this dude: www.linkedin.com/in/robplonski/Ciro Santilli finds it interesting that radioactive decay basically kickstarted the domain of nuclear physics by essentially providing a natural particle accelerator from a chunk of radioactive element.
The discovery process was particularly interesting, including Henri Becquerel's luck while observing phosphorescence, and Marie Curie's observation that the uranium ore were more radioactive than pure uranium, and must therefore contain other even more radioactive substances, which lead to the discovery of polonium (half-life 138 days) and radium (half-life 1600 years).
Discovered by Marie Curie when she noticed that there was some yet unknown more radioactive element in their raw samples, after uranium and polonium, which she published 6 months prior, had already been separated. Published on December 1989 as: Section "Sur une nouvelle substance fortement radio-active, contenue dans la pechblende".
The uranium 238 decay chain is the main source of naturally occurring radium.
Plutonium-based.
Its plutonium was produced at Hanford site.
Trinity Test Preparations by AtomicHeritage (2016)
Source. Appears to be a compilation of several videos, presumably each with their own separate LA-UR, though these are not noted. Credited: "Video courtesy of the Los Alamos National Laboratory Archives", TODO how to search that archive online?Trinity: Getting The Job Done
. Source. Good video, clarifies several interesting technical points:- Gun-type fission weapon were much easier to build as you don't need super synchronized charges as in implosion-type fission weapon. But they are less efficient.
- Plutonium make much more efficient usage of uranium, because you don't need to highly enrich a bunch of Uranium-235 in the first place, but rather just use way less enriched Uranium-235 to produce a bunch of Plutonium by converting Uranium-238
Glass with Uranium added to it to become fluorescent due to Uranium's chemical properties. This is unrelated to Uranium's nuclear properties.
However it was this fluorescence that led Henri Becquerel to discover radioactivity while studying fluorescence, which led him to have Uranium compounds and photographic material in close proximity. I love science I guess.
