Looking at radio-quiet AGN with radio polarimetry

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Silpa Sasikumar
Preeti Kharb


The dominant radio emission mechanism in radio-quiet quasars (RQQs) is an open question. Primary contenders include: low-power radio jets, winds, star-formation and coronal emission. Our work suggests that radio polarization and emission-line studies can help to distinguish between these scenarios and determine the primary contributor. Our multi-frequency, multi-scale radio polarization study has revealed a composite jet and "wind" radio outflow in the radio-intermediate quasar, III Zw 2, as well as in the BALQSO, Mrk 231. Our radio polarization study in conjunction with the [O III] emission-line study of five type 2 RQQs have provided insights on the interplay of jets/winds and emission-line gas. These sources reveal an anti-correlation between polarized radio emission and [O III] emission. This is similar to that observed in some radio-loud active galactic nuclei (AGN) in the literature and suggests that the radio emission could be depolarized by the emission-line gas. Overall, our work suggests that a close interaction between the radio outflow and the surrounding gaseous environment is likely to be responsible for their stunted form in RQ and RI AGN.


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How to Cite
Sasikumar S., Kharb P., 2022. Acta Astrophysica Taurica, vol. 3, no. 1, pp. 17-22. DOI: 10.31059/aat.vol3.iss1.pp17-22
Crimean-2021 AGN Conference proceedings