Program: GN-2022A-FT-108

Galactic winds are proposed to flow into the circumgalactic medium surrounding galaxies, but winds on these scales have rarely been observed. Odd radio circles, or ORCs, are promising candidates for late-stage winds with diameters of several hundred kpc. This is reminiscent of the wind-blown, 100 kpc nebula surrounding the Makani galaxy. However, very little is known about ORCs, including their distances or their connection with nearby galaxies at z = 0.3-0.6. We propose longslit spectroscopy of the five known ORCs to (1) measure the redshift and stellar populations of their central galaxies and (2) search for outflowing warm ionized gas inside the ORCs. This is a timely and ideal proposal for fast turnaround, as the galactic wind hypothesis was just published (March 2022) and the proposed targets (RA =15 to 01) are all visible this summer.