Morphology of the nonspherically decaying radiation beam generated by a rotating superluminal source

Abstract

We consider the nonspherically decaying radiation field that is generated by a polarization current with a superluminally rotating distribution pattern in vacuum, a field that decays with the distance $\subP{R}$ from its source as $\subP{R}^{-1/2}$, instead of $\subP{R}^{-1}$. It is shown (i) that the nonspherical decay of this emission remains in force at all distances from its source independently of the frequency of the radiation, (ii) that the part of the source that makes the main contribution toward the value of the nonspherically decaying field has a filamentary structure whose radial and azimuthal widths become narrower (as $\subP{R}^{-2}$ and $\subP{R}^{-3}$, respectively), the farther the observer is from the source, (iii) that the loci on which the waves emanating from this filament interfere constructively delineate a radiation `subbeam' that is nondiffracting in the polar direction, (iv) that the cross-sectional area of each nondiffracting subbeam increases as $\subP{R}$, instead of $\subP{R}^2$, so that the requirements of conservation of energy are met by the nonspherically decaying radiation automatically, and (v) that the overall radiation beam within which the field decays nonspherically consists, in general, of the incoherent superposition of such coherent nondiffracting subbeams. These findings are related to the recent construction and use of superluminal sources in the laboratory and numerical models of the emission from them. We also briefly discuss the relevance of these results to the giant pulses received from pulsars.

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• Giant Pulses from PSR B1937+21 with widths <= 15 nanoseconds and T_b >= 5 x 10^39 K, the Highest Brightness Temperature Observed in the Universe
• Simultaneous Dual Frequency Observations of Giant Pulses from the Crab Pulsar
• On the Localized superluminal Solutions to the Maxwell Equations
• Giant Pulses -- the Main Component of the Radio Emission of the Crab Pulsar
• The spectral and polarization characteristics of the nonspherically decaying radiation generated by polarization currents with superluminally rotating distribution patterns
• The frequency spectrum of focused broadband pulses of electromagnetic radiation generated by polarization currents with superluminally rotating distribution patterns

Cited by in corpus (7)

• Mechanism of generation of the emission bands in the dynamic spectrum of the Crab pulsar
• The fundamental role of the retarded potential in the electrodynamics of superluminal sources
• The electromagnetic radiation whose decay violates the inverse-square law: detailed mathematical treatment of an experimentally realized example
• Morphology of the nonspherically decaying radiation generated by a rotating superluminal source: reply to comment
• Spectral properties of the nonspherically decaying radiation generated by a rotating superluminal source
• Inadequacies in the conventional treatment of the radiation field of moving sources
• Pulsar-driven Jets in Supernovae, Gamma-Ray Bursts, and the Universe