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arXiv · 2111.03818

Jet-triggered star formation in young radio galaxies

Chetna Duggal·Christopher O'Dea·Stefi Baum·Alvaro Labiano·Raffaella Morganti·Clive Tadhunter·Diana Worrall·Grant Tremblay·Daniel Dicken·Alessandro Capetti
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Abstract

Emission in the ultraviolet continuum is a salient signature of the hot, massive and consequently short-lived, stellar population that traces recent or ongoing star formation. With the aim of mapping star forming regions and morphologically separating the generic star formation from that associated with the galaxy-scale jet activity, we obtained high-resolution HST/UV imaging for a sample of nine compact radio sources. Out of these, seven are known Compact Steep Spectrum (CSS) galaxies that host young, kpc-scale radio sources and hence are the best candidates for studying radio-mode feedback on galaxy scales, while the other two form a control sample of larger sources. Extended UV emission regions are observed in six of the seven CSS sources showing close spatial alignment with the radio-jet orientation. If other mechanisms possibly contributing to the observed UV emission are ruled out, this could be evidence in support of jet-triggered star formation in the CSS phase of radio galaxy evolution.

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Chetna Duggal, Christopher O'Dea, Stefi Baum, Alvaro Labiano, Raffaella Morganti, Clive Tadhunter, Diana Worrall, Grant Tremblay, Daniel Dicken, Alessandro Capetti. 2021-11-06. Jet-triggered star formation in young radio galaxies. https://doi.org/10.1002/asna.20210054

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