Shock Excited Molecules in NGC 1266: ULIRG conditions at the center of a Bulge Dominated Galaxy

E. W. Pellegrini; J. D. Smith; M. G. Wolfire; B. T. Draine; A. F. Crocker; K. V. Croxall; P. van der Werf; D. A. Dale; D. Rigopoulou; C. D. Wilson; E. Schinnerer; B. A. Groves; K. Kreckel; K. M. Sandstrom; L. Armus; D. Calzetti; E. J. Murphy; F. Walter; J. Koda; E. Bayet; P. Beirao; A. D. Bolatto; M. Bradford; E. Brinks; L. Hunt; R. Kennicutt; J. H. Knapen; A. K. Leroy; E. Rosolowsky; L. Vigroux; R. H. B. Hopwood

doi:10.1088/2041-8205/779/2/l19

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arXiv · 1311.3993

Shock Excited Molecules in NGC 1266: ULIRG conditions at the center of a Bulge Dominated Galaxy

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Abstract

We investigate the far infrared spectrum of NGC 1266, a S0 galaxy that contains a massive reservoir of highly excited molecular gas. Using the SPIRE-FTS, we detect the $^{12}$CO ladder up to J=(13-12), [C I] and [N II] lines, and also strong water lines more characteristic of UltraLuminous IR Galaxies (ULIRGs). The 12CO line emission is modeled with a combination of a low-velocity C-shock and a PDR. Shocks are required to produce the H2O and most of the high-J 12CO emission. Despite having an infrared luminosity thirty times less than a typical ULIRG, the spectral characteristics and physical conditions of the ISM of NGC 1266 closely resemble those of ULIRGs, which often harbor strong shocks and large-scale outflows.

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E. W. Pellegrini, J. D. Smith, M. G. Wolfire, B. T. Draine, A. F. Crocker, K. V. Croxall, P. van der Werf, D. A. Dale, D. Rigopoulou, C. D. Wilson, E. Schinnerer, B. A. Groves, K. Kreckel, K. M. Sandstrom, L. Armus, D. Calzetti, E. J. Murphy, F. Walter, J. Koda, E. Bayet, P. Beirao, A. D. Bolatto, M. Bradford, E. Brinks, L. Hunt, R. Kennicutt, J. H. Knapen, A. K. Leroy, E. Rosolowsky, L. Vigroux, R. H. B. Hopwood. 2013-11-15. Shock Excited Molecules in NGC 1266: ULIRG conditions at the center of a Bulge Dominated Galaxy. https://doi.org/10.1088/2041-8205%2F779%2F2%2Fl19

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