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Fusion Science and Technology
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.
M. Sato, A. Isayama
Fusion Science and Technology | Volume 52 | Number 2 | August 2007 | Pages 169-175
Technical Paper | Electron Cyclotron Wave Physics, Technology, and Applications - Part 1 | doi.org/10.13182/FST07-A1496
Articles are hosted by Taylor and Francis Online.
Extended Trubnikov emissivity is evaluated to oblique propagation to the magnetic field in the spherically symmetric relativistic Maxwellian case. Using the extended Trubnikov expression, electron cyclotron emission (ECE) spectra and electron temperature profiles are calculated in a reactor-grade tokamak. We investigate the possibility of electron temperature profile Te(r) measurement from second-harmonic extraordinary (X)-mode ECE by changing the propagation direction. The observation angles all are scanned in solid angle to find out when the relativistic effects of the third-harmonic ECE on second- harmonic ECE decrease are minimal. The measurable Te from second-harmonic X-mode becomes high by increasing the angle between the propagation sight line and the equatorial plane because of the avoidance of the overlap region between the second and third harmonics, but the spatial resolution becomes worse. The antenna is not necessarily located around the equatorial plane. The second X-mode and the fundamental ordinary (O)-mode for the Te(r) measurement from ECE are best in the cases of Te(0) 24 keV and 24 keV Te(0) 50 keV, respectively. When the electron density, the magnetic field, and/or the inverse aspect ratio increase, the measurable Te decreases.
