A new determination of the free-space velocity of electromagnetic waves

@article{Froome1958AND,
  title={A new determination of the free-space velocity of electromagnetic waves},
  author={Kenneth Froome},
  journal={Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences},
  year={1958},
  volume={247},
  pages={109 - 122}
}
  • K. Froome
  • Published 9 September 1958
  • Geology
  • Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences
The paper describes the determination of the free-space phase velocity of electromagnetic waves in vacuo by means of a millimetre-wave interferometer capable of high precision. As already provisionally announced (Froome 1958) the result is: co =299792.50±0.10 km/s, where the variation represents the standard deviation of a single determination in statistical combination with estimated systematic errors. 

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References

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Precision Determination of the Velocity of Electromagnetic Waves
THE free-space phase velocity of electromagnetic waves in vacuo has been measured by means of a millimetre-wave interferometer operating at a frequency of 72 Gc./s., corresponding to a wave-length of
The Refractive Indices of Water Vapour, Air, Oxygen, Nitrogen, Hydrogen, Deuterium and Helium
The method described by Essen and Froome has been used to measure the refractive indices of water vapour, air, oxygen, nitrogen, hydrogen, deuterium and helium at a frequency of 9200 Mc/s. The value