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arXiv · 2204.08973

The [CII] and FIR properties of z>6 radio-loud quasars

Yana Khusanova·Eduardo Bañados·Chiara Mazzucchelli·Sofía Rojas-Ruiz·Emmanuel Momjian·Fabian Walter·Roberto Decarli·Bram Venemans·Emanuele Paolo Farina·Romain Meyer·Feige Wang·Jinyi Yang
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Abstract

There are only five radio-loud quasars currently known within 1 Gyr from the Big Bang ($z>6$) and the properties of their host galaxies have not been explored in detail. We present a NOrthern Extended Millimeter Array (NOEMA) survey of [CII] (158 $\mu$m) and underlying continuum emission of four $z>6$ radio-loud quasars, revealing their diverse properties. J0309+2717 ($z=6.10$) has a bright [CII] line and underlying continuum, implying a starburst with a star-formation rate SFR=$340-1200$ $M_\odot$ yr$^{-1}$. J1429+5447 ($z=6.18$) has a SFR=$520-870$ $M_{\odot}$yr$^{-1}$ and its [CII] profile is consistent with two Gaussians, which could be interpreted as a galaxy merger. J1427+3312 ($z=6.12$) has a moderate SFR=$30-90$ $M_\odot$ yr$^{-1}$. Notably, this is a broad absorption line quasar and we searched for the presence of high-velocity outflows in the host galaxy. Although the NOEMA data reveal a tentative broad component of the [CII] line as wide as $\sim$1400~km~s$^{-1}$, the sensitivity of our current data is not sufficient to confirm it. Finally, P172+18 ($z=6.82$) is undetected in both [CII] and continuum, implying a SFR$<22-40$ $M_{\odot}$yr$^{-1}$. The broad range of SFRs is similar to what is observed in radio-quiet quasars at similar redshifts. If radio jets do not significantly contribute to both [CII] and IR luminosities, this suggest no feedback from the jet on the star formation in the host galaxy.

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Yana Khusanova, Eduardo Bañados, Chiara Mazzucchelli, Sofía Rojas-Ruiz, Emmanuel Momjian, Fabian Walter, Roberto Decarli, Bram Venemans, Emanuele Paolo Farina, Romain Meyer, Feige Wang, Jinyi Yang. 2022-04-19. The [CII] and FIR properties of z>6 radio-loud quasars. https://doi.org/10.1051/0004-6361%2F202243660

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