Pulling back the curtain on shocks and star-formation in NGC 1266 with Gemini-NIFS

Justin Atsushi Otter; Katherine Alatalo; Kate Rowlands; Richard M. McDermid; Timothy A. Davis; Christoph Federrath; K. Decker French; Timothy Heckman; Patrick Ogle; Darshan Kakkad; Yuanze Luo; Kristina Nyland; Akshat Tripathi; Pallavi Patil; Andreea Petric; Adam Smercina; Maya Skarbinski; Lauranne Lanz; Kristin Larson; Philip N. Appleton; Susanne Aalto; Gustav Olander; Elizaveta Sazonova; J. D. T. Smith

arXiv · 2409.17319

Pulling back the curtain on shocks and star-formation in NGC 1266 with Gemini-NIFS

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Abstract

We present Gemini near-infrared integral field spectrograph (NIFS) K-band observations of the central 400 pc of NGC 1266, a nearby (D$\approx$30 Mpc) post-starburst galaxy with a powerful multi-phase outflow and a shocked ISM. We detect 7 H$_2$ ro-vibrational emission lines excited thermally to $T$$\sim$2000 K, and weak Br$\gamma$ emission, consistent with a fast C-shock. With these bright H$_2$ lines, we observe the spatial structure of the shock with an unambiguous tracer for the first time. The Br$\gamma$ emission is concentrated in the central $\lesssim$100 pc, indicating that any remaining star-formation in NGC 1266 is in the nucleus while the surrounding cold molecular gas has little on-going star-formation. Though it is unclear what fraction of this Br$\gamma$ emission is from star-formation or the AGN, assuming it is entirely due to star-formation we measure an instantaneous star-formation rate of 0.7 M$_\odot$ yr$^{-1}$, though the star-formation rate may be significantly higher in the presence of additional extinction. NGC 1266 provides a unique laboratory to study the complex interactions between AGN, outflows, shocks, and star-formation, all of which are necessary to unravel the evolution of the post-starburst phase.

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Justin Atsushi Otter, Katherine Alatalo, Kate Rowlands, Richard M. McDermid, Timothy A. Davis, Christoph Federrath, K. Decker French, Timothy Heckman, Patrick Ogle, Darshan Kakkad, Yuanze Luo, Kristina Nyland, Akshat Tripathi, Pallavi Patil, Andreea Petric, Adam Smercina, Maya Skarbinski, Lauranne Lanz, Kristin Larson, Philip N. Appleton, Susanne Aalto, Gustav Olander, Elizaveta Sazonova, J. D. T. Smith. 2024-09-25. Pulling back the curtain on shocks and star-formation in NGC 1266 with Gemini-NIFS. https://arxiv.org/abs/2409.17319

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