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We present an analysis of 10 ks snapshot Chandra observations of 12 shockedpost-starburst galaxies, which provide a window into the unresolved question ofactive galactic nuclei (AGN) activity in post-starburst galaxies and its rolein the transition of galaxies from actively star forming to quiescence. While7/12 galaxies have statistically significant detections (with 2 more marginaldetections), the brightest only obtained 10 photons. Given the wide variety ofhardness ratios in this sample, we chose to pursue a forward modeling approachto constrain the intrinsic luminosity and obscuration of these galaxies ratherthan stacking. We constrain intrinsic luminosity of obscured power-laws basedon the total number of counts and spectral shape, itself mostly set by theobscuration, with hardness ratios consistent with the data. We also testedthermal models. While all the galaxies have power-law models consistent withtheir observations, a third of the galaxies are better fit as an obscuredpower-law and another third are better fit as thermal emission. If thesepost-starburst galaxies, early in their transition, contain AGN, then these aremostly confined to a lower obscuration ($n_H \leq10^{23}$ cm$^{-2}$) and lowerluminosity ($L_{2-10~ \rm keV}\leq10^{42}$erg s$^{-1}$). Two galaxies, however,are clearly best fit as significantly obscured AGN. At least half of thissample show evidence of at least low luminosity AGN activity, though none couldradiatively drive out the remaining molecular gas reservoirs. Therefore, theseAGN are more likely along for the ride, having been fed gas by the sameprocesses driving the transition.

Are Active Galactic Nuclei in Post-Starburst Galaxies Driving the Change or Along for the Ride?