Oh, wait, no, that probably means no tax cut. Never mind.
Polonium-210 has a half life of only 138 days. Present in small quantities in uranium ores as a result of being produced by decay of uranium-238, it was detected, identified and named by Marie Curie and her husband, Pierre, in 1898 as a result of its highly radioactive nature. While atomic physics had a long way to go in 1898, Curie was able to characterise this as "alpha radiation," now known to be free protons; confusingly, these can also be understood as ionised hydrogen atoms, or hydrogen nucleii. That is not, however, how the polonium that poisoned Litvinenko, reached him. By far the most common source of polonium today, and the only one that could have produced it in the necessary quantity, is artificial production by neutron bombardment of bismuth.
To haul this back into something like coherence, I am looking at a series of events beginning (because it is relevant later), with Walter Bothe and Herbert Becker's 1930 discovery that alpha particles from polonium impinging on beryllium produced an "unusually penetrating radiation." Joliot-Curie and her husband followed up in 1933 with the discovery that this radiation ejected protons from hydrogen-containing targets, implying that it consisted of comparatively massive particles. These were identified by James Chadwick of the Cavendish Laboratory in 1933 as the neutron. It is a indicator of the changes that Big Science have wrought in physics that Chadwick received his Nobel Prize in 1935, and not 1955! Five years later, playing with neutrons led to the discovery of uranium fission. (This is often described as the discovery of atomic fission, but clearly people had figured out that was going on by then!)
The same year, that is, 1933, members of Ernest Lawrence's Radiation Laboratory in Berkeley, then operating the world's most powerful particle accelerator, arrived at the Solvay Conference to make a bumptious claim of having discovered an entirely new and somewhat magical particle, due to unexplained heat gains occurring when they bombarded targets with deuterium. James Chadwick, condescendingly did his best to lead the Americans out of the fever swamps by suggesting contamination of their apparatus. Even more unforgivably, while Lawrence's team continued their chase for the mystery particle, Chadwick and Mark Oliphant identified the contaminant was hydrogen, and showed that the Berkeley group was colliding and fusing hydrogen atoms. The discovery of theoretically-proposed nuclear fusion, occurring well under its brute energy threshold is understandable as quantum tunneling, and explained with difficult maths that Lawrence, was evidently still having trouble with as late as a 1949/50 public argument that probably did not occur on the tarmac of Livermore NAS, but which did happen.
Anyway, a blunter demonstration of the criticism of post-Gilded Age American scientists as well-endowed mediocrities is hard to find.
|Downtown Sydney, March 1950|
Whatever. I'm sure Oliphant's synchrotron was being used for still-classified work into the fundamental building blocks of Nature, and has led to antimatter-catalysed fusion bombs that the Government isn't telling us about because the Government keeps all the cool stuff under wraps in secret underground cities in Wales. (Or Area 51, but that's been done to death on the Internet.) It's certainly not the case that the lab spent the first three years or so trying to make it produce something other than smoke and a fatality. Poor Mr. Fertel's death seems to have been classified into non-history.
Glasgow received £30,000 to be disbursed by P. I. Dee on a new 300 m eV cyclotron and a 30m eV synchotron. These would be used to produce high energy gamma radiation and accelerated protons and deuterons. Low energy detection methods were also to receive support for identification of emissions from several natural and artificial elements including tritium. Bernal's biomolecular lab at Birkbeck received £25,000, plus £1700 to be spread over five years, for work on the optical focussing of x-rays "and the design of a new type of electron-computing device." Blackett's Manchester lab received £4000 for work on cosmic-ray research. "It was hoped that the investigation of penetrating showers, of meson decay, and of extensive showers will lead eventually to increased knowledge of the ultimate structure of matter." The Clarendon lab, under Cherwell, received £64,000 over eight years for the study of low temperatures, the use of liquid helium, and of nuclear physics. Specific projects included the thermal conductivity of glass at all temperatures, the electrical conductivity of low temperature alkali metals and earths, and a mass spectrometer of unprecedented sensitivity and resolution to measure atmospheric helium.
It should be finally noted that, in pursuing the polonium question, I came across the tersely-described electronic neutron initiator, a "compact linear accelerator" that produces neutrons by banging some deuterium or tritium into same, perhaps in a hydride target. The device is popular in the nuclear weapon engineering set because it produces neutrons to order, presumably based on the dial setting of the power battery, making it a key element in variable-yield weapons. The first British electronic neutron initiator was Blue Stone, used in Violet Club, and that's all I know. It sounds like a very clever gadget, and given timelines, It's probably a sideline project for one of the labs that the Nuffield Foundation has just showered with money. Other big developments of the era, such as the use of U-233 alongside U-235, better purification of Pu-240 from Pu-239, and, of course, the "levitated pit" are not doubt underway, the latter more likely at Aldermaston than the universities.
In conclusion, 1950s atomic weapons research if far more interesting and involved than I thought. There's more going on here beyond morbid goulishness, and the links with the early days of Big Science Physics much more profound than I realised. The story of the independent British effort is also interesting from the point of view of industrial cross-fertilisation. In general, we could perhaps come to a clearer understanding of the early and topsy-turvy growth of the nuclear power industry if we had a better understanding of the fine-grain details of atomic weaponeering.