DETECTION OF A HIGH BRIGHTNESS TEMPERATURE RADIO CORE IN THE ACTIVE-GALACTIC-NUCLEUS-DRIVEN MOLECULAR OUTFLOW CANDIDATE NGC 1266

Abstract

We present new high spatial resolution Karl G. Jansky Very Large Array (VLA)\nHI absorption and Very Long Baseline Array (VLBA) continuum observations of the\nActive Galactic Nucleus (AGN)-driven molecular outflow candidate NGC 1266.\nAlthough other well-known systems with molecular outflows may be driven by star\nformation in a central molecular disk, the molecular mass outflow rate reported\nin Alatalo et al. (2011) in NGC 1266 of 13 M$_{\\odot}$ year$^{-1}$ exceeds star\nformation rate estimates from a variety of tracers. This suggests that an\nadditional energy source, such as an AGN, may play a significant role in\npowering the outflow. Our high spatial resolution HI absorption data reveal\ncompact absorption against the radio continuum core co-located with the\nputative AGN, and the presence of a blueshifted spectral component re-affirms\nthat gas is indeed flowing out of the system. Our VLBA observations at 1.65 GHz\nreveal one continuum source within the densest portion of the molecular gas,\nwith a diameter d < 8 mas (1.2 pc), a radio power $P_{\\mathrm{rad}}$ = 1.48\n$\\times$ 10$^{20}$ W Hz$^{-1}$, and a brightness temperature $T_{\\mathrm{b}}$ >\n1.5 x 10$^7$ K that is most consistent with an AGN origin. The radio continuum\nenergetics implied by the compact VLBA source, as well as archival VLA\ncontinuum observations at lower spatial resolution, further support the\npossibility that the AGN in NGC 1266 could be driving the molecular outflow.\nThese findings suggest that even low-level AGNs may be able to launch massive\noutflows in their host galaxies.\n