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The Frequency Evolution of Interstellar Pulse Broadening from Radio Pulsars

O. Loehmer·D. Mitra·Y. Gupta·M. Kramer·A. Ahuja
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Abstract

In this paper we report multi-frequency measurements of pulse broadening times (tau_d) for nine medium dispersion measure (DM $\approx 150-400$ pc cm$^{-3}$) pulsars observed over a wide frequency range. The low frequency data at 243, 325 and 610 MHz are new observations done with the Giant Metrewave Radio Telescope (GMRT). The frequency dependence of tau_d for all but one (PSR B1933+16) of our sources is consistent with the Kolmogorov spectrum of electron density fluctuations in a turbulent medium. PSR B1933+16, however, shows a very flat spectrum as previously observed for high DM pulsars. Our observations combined with earlier published results enable us to study the spectral index of tau_d over the whole observed DM range. While the spectral properties are generally consistent with a Kolmogorov spectrum, pulsars seen along line-of-sights towards the inner Galaxy or complex regions often show deviations from this expected behaviour.

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O. Loehmer, D. Mitra, Y. Gupta, M. Kramer, A. Ahuja. 2004-06-26. The Frequency Evolution of Interstellar Pulse Broadening from Radio Pulsars. https://doi.org/10.1051/0004-6361%3A20035881

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