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The prototypical powerful FR II radio galaxy Cygnus A fits extremely well into the quasar/radio galaxy unified model: high polarization with an angle almost perpendicular to the radio jet and polarized flux showing broad permitted lines. It has been claimed that ionized gas in the torus reveals a very clear torus shape via Bremmstrahlung emission. We rule out the later with an energetic argument, and we constrain the molecular and atomic gas properties with existing observations. The atomic absorption against the core has been shown to match the X-ray column only if the spin temperature is an implausible T s = 1 × 106 K. This points to a molecular medium for the X-ray column |$\log (N_{\rm H} ~[\rm {cm^{-2}}]) \sim 23.5$|⁠. Yet not low-J CO absorption is detected to sensitive limits. The non-detection is surprising given that this powerful radio galaxy hosts a luminous, dust-obscured active nucleus and copious warm molecular hydrogen. These conditions suggest a detectable level of emission. Furthermore, the torus X-ray column density suggests detectable absorption. We explore various possibilities to explain the lack of a signature from warm CO (200–250 K). Specifically, that the radiative excitation by the radio core renders low-J CO absorption below current sensitivities, and that high-J levels are well populated and conducive to producing absorption. We test this hypothesis using archival Hershel /SPIRE FTS observations of Cygnus A of high-J CO lines (14 ≥ J ≥ 4 transitions). Still high-J CO lines are not detected. We suggest that ALMA observations near its high frequency limit can be critical to obtain the signature of molecular line of the torus of Cygnus A. [ABSTRACT FROM AUTHOR]

We present new and archival atomic hydrogen (H  i) observations of 15 of the most massive spiral galaxies in the local Universe (⁠|${M_{\star }}\gt 10^{11} \, {\rm M}_\odot$|⁠). From 3D kinematic modeling of the datacubes, we derive extended H  i rotation curves, and from these, we estimate masses of the dark matter halos and specific angular momenta of the discs. We confirm that massive spiral galaxies lie at the upper ends of the Tully–Fisher relation (mass vs velocity, M  ∝  V 4) and Fall relation (specific angular momentum vs mass, j  ∝  M 0.6), in both stellar and baryonic forms, with no significant deviations from single power laws. We study the connections between baryons and dark matter through the stellar (and baryon)-to-halo ratios of mass f M ≡ M ⋆/ M h and specific angular momentum f j, ⋆ ≡ j ⋆/ j h and f j, bar ≡ j bar/ j h. Combining our sample with others from the literature for less massive disc-dominated galaxies, we find that f M rises monotonically with M ⋆ and M h (instead of the inverted-U shaped f M for spheroid-dominated galaxies), while f j, ⋆ and f j, bar are essentially constant near unity over four decades in mass. Our results indicate that disc galaxies constitute a self-similar population of objects closely linked to the self-similarity of their dark halos. This picture is reminiscent of early analytical models of galaxy formation wherein discs grow by relatively smooth and gradual inflow, isolated from disruptive events such as major mergers and strong active galactic nuclei feedback, in contrast to the more chaotic growth of spheroids. [ABSTRACT FROM AUTHOR]