Upper Bound of Photon Mass - Sources & Review Articles

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Can you tell me the best known upper bound for the photon mass? If possible also provide a link to the source or to a review article on the subject.

Thanks much.:smile:
 
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The particle data group currently quotes :
Photon Mass Bound Destroyed by Vortices E. Adelberger, G. Dvali, A. Gruzinov Phys.Rev.Lett.98:010402,2007
m_\gamma < 10^{-26} eV (assuming Higgs type mass)

"Using plasma physics to weigh the photon" D D Ryutov 2007 Plasma Phys. Control. Fusion 49 B429-B438
m_\gamma < 10^{-18} eV (assuming Yukawa type modification of Maxwell only, or modified dispersion relation)
 
In principle, there is no upper limit to the photon energy, although it has no rest mass. A photon of energy Ephoton can hit an extremely relativistic electron with an energy γm0c2 head on, and the photon energy gets boosted to [STRIKE]γ2 Ephoton[/STRIKE] ~4γ2 Ephoton by Compton scattering.

One way to get an upper limit to the photon rest mass would be to very carefully do energy and momentum transfer in photon absorption:
http://www.aip.org/pnu/2003/split/625-2.html
http://pdg.lbl.gov/2009/listings/rpp2009-list-photon.pdf
Bob S
 
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