Post-starburst ( PSB ) galaxies may be in rapid transition from star-forming to quiescence and are excellent candidates to constrain active galactic nuclei ( AGN ) feedback models .
We study galactic winds in the stacked spectrum of 560 AGN PSBs and that of a control sample of star-forming galaxies in the Sloan Digital Sky Survey ( SDSS ) .
Using a two component ( inter-stellar +wind ) absorption-line model of the \ion Nai doublet , and after accounting for the stellar photospheric absorption , we find that the AGN PSBs have a centroid wind velocity shift of -252 ^ { +64 } _ { -57 } km s ^ { -1 } and a maximum blueshift velocity of -678 ^ { +54 } _ { -53 } km s ^ { -1 } .
In comparison , the control sample , which is matched with the AGN PSBs in redshift , stellar mass , axis-ratio , the 4000 Å break index , Balmer decrement , and WISE 12 \mu m to 4.6 \mu m flux ratio , has a centroid wind velocity shift of -119 ^ { +33 } _ { -41 } km s ^ { -1 } and a maximum velocity of -406 ^ { +51 } _ { -61 } km s ^ { -1 } .
The equivalent widths due to the winds in both samples are similar : 0.36 ^ { +0.10 } _ { -0.07 } Å for the AGN PSBs and 0.24 ^ { +0.07 } _ { -0.06 } Å for the control sample .
Despite having a higher velocity , the observed winds in the AGN PSBs are still not powerful enough to sweep significant amounts of gas out of the halos of the host galaxies .
We also detect winds of similar velocities in the stacked spectra of shocked and quenched PSBs .