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The orientation of the Seyfert nucleus in Markarian 348

S. Anton·A. Thean·A. Pedlar·I. W. A. Browne
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Abstract

Multi-frequency observations of Mrk 348 are presented consisting of 2 epochs of MERLIN data at 5 GHz, ISOPHOT data at 170, 90, 60 and 25 micron, NOT images at U, B, R and I bands and data at 1350 micron from the archive for SCUBA. The new optical images reveal a disrupted arm that ends towards the eastern companion of Mrk 348, consistent with the hypothesis that Mrk 348 and its companion form an interacting system. 5 GHz MERLIN imaging shows that only one of the radio components of Mrk 348 is polarized (%P=5). The broadband spectrum of Mrk 348 is flat between the radio and millimetre bands, suggesting that synchrotron emission extends to high frequencies. Mrk 348 has many of the characteristics of a radio-loud object. We discuss the orientation of the radio axis of Mrk 348 with respect to the line of sight. We conclude that the evidence is conflicting, and the geometry in Mrk 348 is not well-described by a simple edge-on or face-on model.

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S. Anton, A. Thean, A. Pedlar, I. W. A. Browne. 2002-07-08. The orientation of the Seyfert nucleus in Markarian 348. https://doi.org/10.1046/j.1365-8711.2002.05763.x

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