The high brightness temperature of B0529+483 revealed by RadioAstron and implications for interstellar scattering. Issue 3 (21st November 2017)

• Record Type: Journal Article
• Authors: Pilipenko, S V; Kovalev, Y Y; Andrianov, A S; Bach, U; Buttaccio, S; Cassaro, P; Cimò, G; Edwards, P G; Gawroński, M P; Gurvits, L I; Hovatta, T; Jauncey, D L; Johnson, M D; Kovalev, Yu A; Kutkin, A M; Lisakov, M M; Melnikov, A E; Orlati, A; Rudnitskiy, A G; Sokolovsky, K V; Stanghellini, C; de Vicente, P; Voitsik, P A; Wolak, P; Zhekanis, G V
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 474:Issue 3(2018)
• Page Start: 3523
• Page End: 3534
• Publication Date: 2017-11-21
• Subjects: scattering -- galaxies: jets -- quasars: general -- quasars: individual (B0529+483) -- radio continuum: galaxies; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stx2991
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: The high brightness temperatures, T b ≳ 10 13 K, detected in several active galactic nuclei by RadioAstron space VLBI observations challenge theoretical limits. Refractive scattering by the interstellar medium may affect such measurements. We quantify the scattering properties and the sub-mas scale source parameters for the quasar B0529+483. Using RadioAstron correlated flux density measurements at 1.7, 4.8, and 22 GHz on projected baselines up to 240 000 km we find two characteristic angular scales in the quasar core, about 100 and 10 μas. Some indications of scattering substructure are found. Very high brightness temperatures, T b ≥ 10 13 K, are estimated at 4.8 and 22 GHz even taking into account the refractive scattering. Our findings suggest a clear dominance of the particle energy density over the magnetic field energy density in the core of this quasar.