2001/11/15 by I. H. Cairns, Iver H. Cairns, S. Johnston +1 · 2 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Gamma-ray bursts and supernovae #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1086/338359
7 pages, 4 figures. In press at ApJ Letters - scheduled for December 10 issue
arxiv created 2001/11/15 · openalex publication_date 2001/12/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
Individual pulses from pulsars have intensity phase profiles that differ widely from pulse to pulse, from the average profile, and from phase to phase within a pulse. Widely accepted explanations for pulsar radio emission and its time variability do not exist. In this Letter, by analyzing data near the peak of the Vela pulsar's average profile, we show that the variability of the Vela pulsar corresponds to lognormal field statistics, consistent with the prediction of stochastic growth theory (SGT) for a purely linear system close to marginal stability. The variability of the Vela pulsar is therefore a direct manifestation of an SGT state, and the field statistics constrain the emission mechanism to be linear (either direct or indirect), ruling out nonlinear mechanisms such as wave collapse. Field statistics are thus a powerful and potentially widely applicable tool for understanding variability and constraining mechanisms and source characteristics of coherent astrophysical and space emissions.