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arXiv · 2009.06447

Optical study of PKS B1322-110, the intra-hour variable radio source

Juan P. Madrid·Artem V. Tuntsov·Mischa Schirmer·Mark A. Walker·Carlos J. Donzelli·Keith W. Bannister·Hayley E. Bignall·Jamie Stevens·Cormac Reynolds·Simon Johnston
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Abstract

Observations with the Australia Telescope Compact Array revealed intra-hour variations in the radio source PKS B1322-110 (Bignall et al. 2019). As part of an optical follow-up, we obtained Gemini Halpha and Halpha continuum (HalphaC) images of the PKS B1322-110 field. A robust 19-sigma detection of PKS B1322-110 in the Halpha-HalphaC image prompted us to obtain the first optical spectrum of PKS B1322-110. With the Gemini spectrum we determine that PKS B1322-110 is a flat-spectrum radio quasar at a redshift of z=3.007 +/- 0.002. The apparent flux detected in the Halpha filter is likely to originate from HeII emission redshifted precisely on the Galactic Halpha narrow-band filter. We set upper limits on the emission measure of the Galactic plasma, for various possible cloud geometries.

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Juan P. Madrid, Artem V. Tuntsov, Mischa Schirmer, Mark A. Walker, Carlos J. Donzelli, Keith W. Bannister, Hayley E. Bignall, Jamie Stevens, Cormac Reynolds, Simon Johnston. 2020-09-14. Optical study of PKS B1322-110, the intra-hour variable radio source. https://doi.org/10.3847/1538-4357%2Fabaaaf

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