Integral field unit spectroscopy of the stellar disk truncation region of NGC 6155

摘要

Like the majority of spiral galaxies, NGC 6155 exhibits an exponential surface brightness profile that steepens significantly at large radii. Using the VIRUS-P integral field unit 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 μ_V ～ 24 mag arcsec~(-2).