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arXiv · 0901.0718

A forming, dust enshrouded disk at z=0.43: the first example of a late type disk rebuilt after a major merger?

F. Hammer·H. Flores·Y. B. Yang·E. Athanassoula·M. Puech·M. Rodrigues·S. Peirani
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Abstract

Abreg: By combining HST/UDF imagery with kinematics from VLT/GIRAFFE we derive a physical model of distant galaxy J033245.11-274724.0 in a way similar to what can be done in the nearby Universe. Here we study the properties of a distant compact LIRGs galaxy. Given the photometric and spectro photometric accuracies, we can decompose the galaxy in sub components and correct them for reddening. The galaxy is dominated by a dust enshrouded disk revealed by UDF imagery. The disk radius is half that of the Milky Way and the galaxy have a SFR=20Mo/yr. Morphology and kinematics show that gas and stars together spiral inwards rapidly to feed the disk and the central regions. A combined system of a bar and two non rotating spiral arms regulates the material accretion, induces large sigma, with sigma larger than 100 km/s and redistributes the angular momentum (AM). The detailed physical properties resemble to the expectations from modeling a merger of two equal mass, gaseous rich galaxies, 0.5 Gyr after the merger. In its later evolution, this galaxy could become a late type galaxy which falls on the T-F relation, with an AM mostly induced by the orbital AM of the merger.

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F. Hammer, H. Flores, Y. B. Yang, E. Athanassoula, M. Puech, M. Rodrigues, S. Peirani. 2009-02-02. A forming, dust enshrouded disk at z=0.43: the first example of a late type disk rebuilt after a major merger?. https://doi.org/10.1051/0004-6361%3A200810488

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