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The Nuclear Odyssey

Can we reach the island of stability?

I wanted to study this topic for a long time. Nuclear physics has always fascinated me. The subatomic realm is beautiful and the quest for new elements, going beyond the periodic table. Making elements that nature itself hasn't is such a incredible feat. We have gone past Uranium to Ogannesson. But these elements have been ephemeral and exist for times so small we can't fathom. Can we go beyond? Our present physics tells us that there could exist an "island" of elements beyond a unstable "sea" where there could exist stable nuclei. Will we ever be able to cross the choppy waters of the nuclear sea and land on the island of stability?

This blog will be very informal[more like a diary] and I'll keep adding to it every day as I learn more. There'll be a bunch of rabbitholes but hopefully in the end my aim is to understand the current physics and the future of these mystical elements. 

Jan 29, 2025 

Day 1: 

Islands are such beautiful things if you think about it. Distant lands surrounded by turquoise and sapphire shades of water. The water surface trembling as the wind blows and sending sparks of sunlight towards you. The seclusion of these pristine paradises makes them ever more alluring to us. The sound of the waves rumbling and the myriad colors of the sunset brings peace to anyone. It evokes our universal longing for discovery. To go somewhere no has one gone before. Islands stand as a metaphor for the human longing for getting close to our fantasies and fears.
[I do need to read more poetry] 

Islands were always cool. In the game Pokemon Emerald,there was something called the mirage island. The reason it was called that is because you cannot access it like the other parts of the map. It only appears when a random number generated between 0 and 65535 [65535 is equal to 2^{16}-1,highest number that is representable by an unsigned 16 bit binary number]. If this randomly generated number matches the first two values of the personality value of any Pokemon you carry,then the island will appear.[6/65536~1/10923 chance]. Some people did see it by a few tricks here and there[have to learn about the game mechanics].
I never saw it. I have the save file though. Maybe I'll open it someday.

Location of mirage island in the Hoenn region

Recently, I watched The Island Closest to Heaven (1984) , a adaptation of Katsuri Morimura's novel by Nobuhiko Obayashi. It follows the story of a girl who travels to New Caledonia, an archipelago in the Pacific. Her father told her about an island made of white coral and drenched in the golden hues of sunlight. He promised to go together with her for he believed it was closest to heaven. Many years later, Mari, now a 19 year old decided to travel there alone as her father had passed away. But as she travelled across the island,making new friends the film introduces a puzzle. Is the place that her father told so dreamingly about a physical place on the island or something imaginary and metaphorical? The movie follows her journey of realizing what her "island closest to heaven" is. Obayashi captures the natural beauty of New Caledonia and paired with the calm music throughout the movie makes it a good one to watch. There was also a mention of the "green flash" when Yuichi took Mari to see the sunset.  

We all need to find our island closest to heaven

I have been recently more into watching asian films. Understanding a foreign language is certainly a hurdle here. But hurdles make the journey more exciting[Still trying to memorize Hiragana].


Speaking of islands the first detonation of a thermonuclear device, Ivy Mike [10 megaton] was done on the island Elugelab in Enewetak Atoll,Marshall Islands in November of 1952.
[I am working on understanding the first nuclear detonation test, Trinity, neutron diffusion, implosion mechanism and all the relevant physics]
Fireball of Ivy Mike. Reminds me of the final scene in Nausicaa: Valley of the Wind


A crater of around 2 km in diameter was formed. The radioactive debris fell on ships upto 56 km away and the atoll was heavily contaminated. Are we destined with technological progress bringing about the destruction of the environment? [This is a important topic and I'll read more about it and come back to it later]
Enewetak atoll.The crater by 
Ivy mike is the bigger one of the two.


Albert Ghiorso [American nuclear scientist co-discovered 12 chemical elements on the periodic table] was the first to identify Einsteinium in the radioactive fallout from this thermonuclear test. The high neutron flux density during the detonation of the bomb made it possible that the heavy isotopes generated could absorb neutrons before disintegration. 

[Learning about laboratory synthesis of transuranic elements]
After the discovery of nuclear fission in 1938 by Otto Hahn,Lise Meitner and Fritz Strassmann,based on his liquid drop model of the nucleus Bohr was able to come to the conclusion that the rare isotope of uranium U-235 was responsible for fission with neutrons and not the abundant U-238. He published his findings in this paper with John Wheeler.[Time to read this paper]




Day 2: 

Jan 30, 2025
 
Its time to go to the beach. We start from the last stable elements and then travel to the actinides and the transuranic elements towards the coastline where we can finally get a glimpse of the island of stability. In Yuri Oganessian's paper he shows this beautiful picture of this landscape. We can see how close we are.[Time to read it] The colors show the half-lives of these elements. Unstable elements decay and half life is the time that after which there would be a 50% chance that the atom would have decayed. Radioactive nuclides half lives' go from yoctoseconds to quettaseconds. Apparently Tellurium-128 has a half life of 69 quettaseconds, 160 trillion times greater than the current age of the universe. Well wow how? [Gotta study this even more] So apparently there is an article on it by the founder of Autodesk[gotta look into it more]. Well apparently this will not be the final say on it, as with more experimentation we could find more decay chains for the "stable"[we have not observed any radioactivity in them] elements which can push the record even further.
The island is visible now

Was playing around with pynucastro. It enables the creation of reaction networks to use in simulation codes. Super cool package. We can do astrophysical networks and determine the rates of the pp-chain and CNO cycle. Nuclear reactions that happen inside stars with mass around our sun.[I read some nuclear astrophysics in my undergrad but will revisit it soon]
binding energy per nucleon of the elements using pynucastro

Binding energy comes from the semi emprical mass formula [will do a deep dive into this in the future]

In the mechanism of nuclear fission according to N.Bohr and J.Wheeler, fission in uranium is prevented by a potential barrier of 6 MeV. They predicted this by modelling the deformation of the nucleus during fission as a charged liquid drop. If an energy greater than 6 MeV the uranium nucleus will split. Adding more protons further decreases the barrier making spontaneous decay more probable. And according to the liquid drop model this will occur after we go beyond 100 protons (Fermium). 
Wait what then how did we get to element number 118? There must be something more intricate happening here.Looks like its time to derive the Bohr Wheeler spontaneous fission limit.
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