Letter | Published:

Amplification of cosmic Čerenkov radiation

Naturevolume 266pages513514 (1977) | Download Citation



EJECTION of relativistic or ultra-relativistic electrons is used in most quasar models to explain the very high luminosities of these objects. The velocity distribution of matter is taken as4 is the mass fraction external to the radius r; F0 ≈ 105; ρ is the density and the Lorentz factor is γ0 = (1−u2/c2)−1/2; u and c are velocities of the particle and the light, respectively. The observed luminosities are then explained on the basis of inverse Compton scattering of synchrotron radiation to the optical frequencies. In the radio frequency range the observed emission spectrum shows polarisation and also follows the power law, suggesting a synchrotron emission mechanism supporting these models, which essentially lead to the existence of finite magnetic fields in the quasars1,2. In these conditions, some Cerenkov radiation is also produced4,5. We suggest here that this radiation is amplified, and may account for the observed luminosity of quasars.

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  1. Physical Research Laboratory, Ahmedabad, 380009, India

    • V. H. KULKARNI


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