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High Density Molecular Gas in the IR-bright Galaxy System VV114

Daisuke Iono·Paul T. P. Ho·Min S. Yun·Satoki Matsushita·Alison B. Peck·Kazushi Sakamoto
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Abstract

New high resolution CO(3-2) interferometric map of the IR-bright interacting galaxy system VV114 observed with the Submillimeter Array (SMA) reveal a substantial amount of warm and dense gas in the IR-bright but optically obscured galaxy, VV114E, and the overlap region connecting the two nuclei. A 1.8 x 1.4 kpc concentration of CO(3-2) emitting gas with a total mass of 4 x 10^9 Msun coincides with the peaks of NIR, MIR, and radio continuum emission found previously by others, identifying the dense fuel for the AGN and/or the starburst activity there. Extensive CO(2-1) emission is also detected, revealing detailed distribution and kinematics that are consistent with the earlier CO(1-0) results. The widely distributed molecular gas traced in CO(2-1) and the distributed discrete peaks of CO(3-2) emission suggest that a spatially extended intense starbursts may contribute significantly to its large IR luminosity. These new observations further support the notion that VV114 is approaching its final stage of merger, when violent central inflow of gas triggers intense starburst activity possibly boosting the IR luminosity above the ultraluminous threshold.

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Daisuke Iono, Paul T. P. Ho, Min S. Yun, Satoki Matsushita, Alison B. Peck, Kazushi Sakamoto. 2004-03-17. High Density Molecular Gas in the IR-bright Galaxy System VV114. https://doi.org/10.1086/420784

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