Question

In 2015, researchers at Parkes Observatory found that mysterious emissions called perytons were caused by people prematurely opening the microwave at lunchtime. Answer the following about the physics involved, for 10 points each.
[10e] The perytons had similar dispersion to, and were often mistaken for, astronomical “fast bursts” in this longest-wavelength region of the EM spectrum.
ANSWER: radio waves [accept fast radio bursts]
[10h] The perytons were emitted by this radiation-producing component of the microwave. These devices consisting of vacuum tubes with many resonant chambers were used in World War II to generate radar signals.
ANSWER: cavity magnetron
[10m] The peryton signals strangely spiked at 1.4 gigahertz because changing voltage changed the cavity’s resonant condition, causing the magnetron to “hop” between these things. TE, TM, and TEM are examples of these things for electromagnetic waves.
ANSWER: modes [or normal modes or modes of propagation]
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Summary

Data

Oxford ADurham A1001020
Imperial ACambridge B100010
Oxford CKCL0000
KielDurham B1001020
BristolOxford B1010020
SheffieldCambridge C100010
WarwickImperial B100010
EdinburghCambridge A100010