A map of the horizontal flows in the solar convection zone

The first map of the horizontal flows as a function of depth and heliocentric position in the solar convection zone is presented. The map is inferred from a least-squares smoothness-constrained inversion of velocities measured from ring diagrams of the solar p-mode oscillations. The data provide information in four longitude regions at a latitude just south of the solar equator. The presence of several features is suggested by the results:

(1)	A prograde directed longitudinal jet between the hydrogen and first helium ionization zone, reversing direction to retrograde below the second helium ionization zone.
(2)	A equatorward directed latitudinal flow above the second helium ionization zone.
(3)	A poleward latitudinal flow below the second helium ionization zone, but only in one of the four longitude bands. A large active region was present in this band, but not in two of the other bands, suggesting a possible relationship between the activity and the different flow pattern.

The magnitude of the flows is substantial, reaching some 450 m s^–1 for the longitudinal jet, and 150 m s^–1 for the latitudinal flow. Possible systematic errors and the physical consequences of the flows are discussed.