A Chandra Snapshot Survey of IR-bright LINERs: A Possible Link Between Star Formation, AGN Fueling, and Mass Accretion

Abstract

We present results from a high resolution X-ray imaging study of nearby LINERs observed by Chandra. This study complements and extends previous X-ray studies of LINERs, focusing on the under-explored population of nearby dust-enshrouded infrared-bright LINERs. The sample consists of 15 IR-bright LINERs (L_FIR/L_B > 3), with distances that range from 11 to 26 Mpc. Combining our sample with previous Chandra studies we find that ~ 51% (28/55) of the LINERs display compact hard X-ray cores. The nuclear 2-10 keV luminosities of the galaxies in this expanded sample range from ~ 2 X 10^38 ergs s^-1 to ~ 2 X 10^44 ergs s^-1. We find an intriguing trend in the Eddington ratio vs. L_FIR and L_FIR/L_B for the AGN-LINERs in the expanded sample that extends over seven orders of magnitude in L/L_Edd. This correlation may imply a link between black hole growth, as measured by the Eddington ratio, and the star formation rate (SFR), as measured by the far-IR luminosity and IR-brightness ratio. If the far-IR luminosity is an indicator of the molecular gas content in our sample of LINERs, our results may further indicate that the mass accretion rate scales with the host galaxy's fuel supply. We discuss the potential implications of our results in the framework of black hole growth and AGN fueling in low luminosity AGN. (Abridged)