Searching For Fossil Evidence of AGN Feedback in WISE-Selected Stripe-82
  Galaxies By Measuring the Thermal Sunyaev-Zel'dovich Effect With the Atacama
  Cosmology Telescope
  We directly measure the thermal energy of the gas surrounding galaxies
through the thermal Sunyaev-Zel'dovich (tSZ) effect. We perform a stacking
analysis of microwave background images from the Atacama Cosmology Telescope,
around 1179 massive quiescent elliptical galaxies at 0.5 <= z <= 1.0 ('low-z')
and 3274 galaxies at 1.0 <= z <= 1.5 ('high-z'), selected using data from the
Wide-Field Infrared Survey Explorer All-Sky Survey and the Sloan Digital Sky
Survey (SDSS) within the SDSS Stripe-82 field. The gas surrounding these
galaxies is expected to contain energy from past episodes of active galactic
nucleus (AGN) feedback, and after using modeling to subtract undetected
contaminants, we detect a tSZ signal at a significance of 0.9-sigma for our
low-z galaxies and 1.8-sigma for our high-z galaxies. We then include data from
the high-frequency Planck bands for a subset of 227 low-z galaxies and 529
high-z galaxies and find low-z and high-z tSZ detections of 1.0-sigma and
1.5-sigma, respectively. These results indicate an average thermal heating
around these galaxies of 5.6(+5.9/-5.6) x 10^60 erg for our low-z galaxies and
7.0(+4.7/-4.4) x 10^60 erg for our high-z galaxies. Based on simple heating
models, these results are consistent with gravitational heating without
additional heating due to AGN feedback.
