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Questions tagged [nuclear-physics]

Nuclear physics is the field of Physics that studies atomic nuclei and their constituents and interactions. It started with the discovery of radioactivity by Henri Becquerel in 1896, together with the discovery of the electron by J. J. Thomson a year later.

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What new physics was discovered or needed as a result of the Manhattan Project?

I originally asked this question on the Physics StackExchange and was told to migrate it here. I've tightened up the question a bit. I recently got into a discussion with colleagues regarding ...
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Historic misidentification of transuranium elements?

In 1934, Fermi and his team irradiated uranium (Z=92) with neutrons in order to synthesize element 93. They (and others) did not recognize that they had performed a nuclear fission of uranium. The ...
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Why did “cold fusion” come to mean Fleischmann-Pons fusion instead of μCF?

Muon-catalysed fusion is obtained at low temperatures, although as of 2018 its energy yield is less than the muon production requirements. The term "cold fusion" was first used in the 1950s, to refer ...
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From a historical perspective why is beta decay associated with an anti neutrino instead of a neutrino?

I know it sounds like a silly question but didn't both Pauli and Fermi hint at Beta decay missing a particle to carry away a small amount of it's energy or mass but why is this an anti neutrino ? The ...
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When was it first noticed, or demonstrated, that radioactive material became warm?

Perusing the Radioactive Thermoelectric Generator or rtg tag in Space SE will show how important these items are for Space exploration both as a source of heat to ...
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Did the B reactor at Hanford make use of U235 without having U238 enriched ?

I asked a question in similar vain for the "Fermi pile", however this reactor is different. It's purpose was to produce plutonium...now I understand the advantage of that since plutonium can be ...
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Where did Fermi get the U235 for the first nuclear pile?

I am puzzled as to where or who produced the U235 for the first nuclear pile. I read that graphite was used as a neutron moderator but only .7 % of natural uranium is U235. He must have gotten it ...
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What is the history of how a neutron moderator is chosen in nuclear chain reactions?

Maybe the wrong area...should be physics maybe...but there is some history here as well. I became interested in knowing how Fermi came to pick graphite as a neutron moderator. For example beryllium ...
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Did anything significant happened in 1960s that involve neutron?

I am playing with Ngram viewer and I plugged in several subatomic particles and saw this graph (see attached). The term "proton" was used starting the 1920 and neutron was discovered in 1932, which is ...
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Why did it take an army of physicists, working on a huge complex, so long to produce a working nuclear device, while it seems so easy in theory?

I think most of us know about the construction of the first atomic bomb at Los Alamos, with Robert Oppenheimer (who said he became "The destroyer of worlds", which goes to show he regretted his ...
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What was the boat-carried nuclear bomb envisaged by the Einstein–Szilárd letter?

In the letter to FDR during WWII written by Szilárd and signed by Einstein, a rather massive (emphasis added) nuclear bomb is theorized: This new phenomenon would also lead to the construction of ...
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Has anybody of famous physists thought nuclear weapons was impossible?

In the history of science and technology, there are some cases, when scientists don't believe into something, which appear real later. For example, Bill Gates was saying 640K is sufficient to any ...
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Before the discovery of the neutron, how did scientists explain standard atomic weights?

The neutron was predicted in 1920 and discovered 12 years later. Before this time, how did scientists explain standard atomic weights? For example, Lithium has a standard atomic weight of about 6.9 ...
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To what extent were the scientists involved in the Manhattan project aware of the goals?

I want to understand the extent to which scientists and technicians employed in the Manhattan project understood that they were building a bomb that would kill hundreds of thousands of people. ...
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Is there any history into the methodology that Balmer used for the spectral line formula?

What I am referring to is the Balmer formula as it appears in Wikipedia. To come up with this series by trial and error along with its constants is asking a little too much but I can't understand how ...
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When was the geological timescale determined by radiometric dating?

Long before radiometric dating, Earth's history was divided into a timescale with named units based on bands of rocks and fossils. Thus events could be placed in order by superposition. Some time ...
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Who first noticed violation of aufbau principle of elements like Cr, Cu, Pd, Au, and how?

It is often referred to as 'anomalous electron configurations' or 'unusual order of filling of orbitals' of a few elements e.g. Cr, Cu, Nb, Mo, Ru, Rh, Pd, Au etc.
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Why didn't Germany succeed in building a nuclear bomb in second world war?

Otto Hahn (a german) found out about nuclear fission in 1938, so that should have given the Germans a head start in developing a nuclear bomb. However they did not succeed in doing so during WWII. I'...
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Lise Meitner's contribution to this experimental apparatus and research effort?

I am reading a NYTimes obituary of Otto Hahn and the discovery of fission, and I've asked in physics SE about the function of the apparatus shown in that article. The system shown demonstrated the ...