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arXiv · 1112.6091

Detection of CO(J=1-0) Emission from Barred Spiral Galaxies at z~0.1

Kana Matsui·Kazuo Sorai·Yoshimasa Watanabe·Nario Kuno
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Abstract

We present the results of CO (J=1-0) observations towards nine barred spiral galaxies at z=0.08-0.25 using the 45-m telescope at Nobeyama Radio Observatory (NRO). This survey is the first one specialized for barred spiral galaxies in this redshift range. We detected CO emission from six out of nine galaxies, whose CO luminosity (L_CO') ranges (1.09-10.8)\times10^9 K km s^{-1} pc^2. These are the infrared (IR) dimmest galaxies that have ever been detected in CO at z~0.1 to date. They follow the L_CO'-L_IR relation among local spiral galaxies, Luminous Infrared Galaxies (LIRGs), Ultra-Luminous Infrared Galaxies (ULIRGs) and Sub-millimeter Galaxies (SMGs). Their L_CO' and L_IR are higher than that of local spiral galaxies which have been detected in CO so far, and L_IR/L'_CO, which is a measure of star formation efficiency, is comparable to or slightly higher than that of local ones. This result suggests that these galaxies are forming stars more actively than local spirals galaxies simply because they have more fuel.

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Kana Matsui, Kazuo Sorai, Yoshimasa Watanabe, Nario Kuno. 2011-12-28. Detection of CO(J=1-0) Emission from Barred Spiral Galaxies at z~0.1. https://doi.org/10.1093/pasj%2F64.3.55

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