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arXiv · 1005.0851

IFU Spectroscopy of the Stellar Disk Truncation Region of NGC 6155

Peter Yoachim·Rok Roškar·Victor P. Debattista
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Abstract

Like the majority of spiral galaxies, NGC 6155 exhibits an exponential surface brightness profile that steepens significantly at large radii. Using the VIRUS-P IFU spectrograph, we have gathered spatially resolved spectra of the system. Modifying the GANDALF spectral fitting routine for use on the complex stellar populations found in spirals, we find that the average stellar ages increase significantly beyond the profile break radius. This result is in good agreement with recent simulations that predict the outskirts of disk galaxies are populated through stellar migration. With the ability to bin multiple fibers, we are able to measure stellar population ages down to mu_V~24 mag/sq arcsec.

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Peter Yoachim, Rok Roškar, Victor P. Debattista. 2010-05-14. IFU Spectroscopy of the Stellar Disk Truncation Region of NGC 6155. https://doi.org/10.1088/2041-8205%2F716%2F1%2Fl4

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