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Latest News
The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
R. Fitzpatrick
Fusion Science and Technology | Volume 59 | Number 3 | April 2011 | Page 625
Appendix A | Fourth ITER International Summer School (IISS2010) / Extended Abstracts | doi.org/10.13182/FST11-A11706
Articles are hosted by Taylor and Francis Online.
Tearing modes are magnetohydrodynamic (MHD) instabilities that often limit fusion plasma performance in tokamaks. As the name suggests, tearing modes tear and reconnect magnetic field lines, in the process converting nested toroidal flux surfaces into helical magnetic islands. Such islands degrade plasma confinement because heat and particles are able to travel radially from one side of an island to another by flowing along magnetic field lines, which is a relatively fast process, instead of having to diffuse across magnetic flux surfaces, which is a relatively slow process. [first paragraph from extended abstract]
