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Properties of the Scattering Screen in Front of Scintillating Quasar PKS 1257-326

H. E. Bignall·D. L. Jauncey·J. E. J. Lovell·A. K. Tzioumis·J-P. Macquart·L. Kedziora-Chudczer
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Abstract

PKS 1257-326 is a quasar showing extremely unusual, rapid interstellar scintillation (ISS), which has persisted for at least a decade. Simultaneous observations with the VLA and ATCA, combined with ATCA monitoring over several years, have revealed some properties of the turbulent ionized medium responsible for the ISS of PKS 1257-326. The scattering occurs in an unusually nearby (~10 pc), localized "screen". The scintillation pattern is highly anisotropic with axial ratio more than 10:1 elongated in a northwest direction on the sky. Recent findings and implications for small-scale ionized structures in the ISM are discussed.

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H. E. Bignall, D. L. Jauncey, J. E. J. Lovell, A. K. Tzioumis, J-P. Macquart, L. Kedziora-Chudczer. 2007-02-01. Properties of the Scattering Screen in Front of Scintillating Quasar PKS 1257-326. https://arxiv.org/abs/astro-ph/0702026

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