2008/04/24 by Simon Johnston, S. Johnston, A. Karastergiou +3 · 71 citations
Earth and Planetary Sciences · Physics and Astronomy · #Advanced Frequency and Time Standards #Astronomy #Astrophysics #Binary pulsar #Geophysics and Gravity Measurements #Green Bank Telescope #Magnetic field #Magnetosphere #Millisecond pulsar #Physics #Polarization (electrochemistry) #Pulsar #Pulsars and Gravitational Waves Research #Range (aeronautics) #Telescope #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13379.x
published in Monthly Notices of the Royal Astronomical Society 388(1), 261-274 (Oxford University Press) · Accepted for publication in MNRAS. 15 pages
arxiv created 2008/04/24 · openalex publication_date 2008/06/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We have observed a total of 67 pulsars at five frequencies ranging from 243 to 3100 MHz. Observations at the lower frequencies were made at the Giant Metre-Wave Telescope in India and those at higher frequencies at the Parkes Telescope in Australia. We present profiles from 34 of the sample with the best signal-to-noise ratio and the least scattering. The general ‘rules’ of pulsar profiles are seen in the data; profiles get narrower, the polarization fraction declines and outer components become more prominent as the frequency increases. Many counterexamples to these rules are also observed, and pulsars with complex profiles are especially prone to rule breaking. We hypothesize that the location of pulsar emission within the magnetosphere evolves with time as the pulsar spins down. In highly energetic pulsars, the emission comes from a confined range of high altitudes, in the middle range of spin down energies the emission occurs over a wide range of altitudes whereas in pulsars with low spin-down energies it is confined to low down in the magnetosphere.