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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
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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. R. Brown, M. Kaur
Fusion Science and Technology | Volume 75 | Number 4 | May 2019 | Pages 275-282
Technical Paper | doi.org/10.1080/15361055.2019.1579622
Articles are hosted by Taylor and Francis Online.
Magnetothermodynamics is the study of compression and expansion of magnetized plasma with an eye toward identifying equations of state (EOSs) for magneto-inertial fusion experiments. We present recent results from Swarthmore Spheromak Experiment (SSX) experiments on the thermodynamics of compressed magnetized plasmas called Taylor states. In these experiments, we generate twisted flux ropes of magnetized, relaxed plasma accelerated from one end of a 1.5-m-long copper flux conserver and observe their compression in a closed conducting boundary installed at the other end. Plasma parameters are measured during compression. The instances of ion heating during compression are identified by constructing a pressure-volume diagram using measured density, temperature, and volume of the magnetized plasma. While we only measure compression up to 30%, we speculate that if higher compression ratios could be achieved, the compressed Taylor states could form the basis of a new kind of fusion engine. The theoretically predicted magnetohydrodynamic (MHD) and double-adiabatic [Chew-Goldberger-Low (CGL)] EOSs are compared to experimental measurements to estimate the adiabatic nature of the compressed plasma. Since our magnetized plasmas relax to an equilibrium described by MHD, one might expect their thermodynamics to be governed by the corresponding EOS. However, we find that the MHD EOS is not supported by our data. Our results are more consistent with the parallel CGL EOS suggesting that these weakly collisional plasmas have most of their proton energy in the direction parallel to the magnetic field.