Comparison of TD and LCT maps at the equator. All maps are based on 8 h of HMI images (intensity and Doppler velocity) taken on 1 May 2010 and have been band-pass filtered around kR_⊙ = 100. The color bar limits are set to the maximum absolute value of the corresponding map and symmetrized around zero. Left column: divergence-sensitive travel times τ^oi for f modes as well as LCT horizontal divergence div_h. Right column: circulation velocities v^ac for TD as well as LCT vertical vorticity ω_z. The TD τ^ac maps were converted into velocity maps by pointwise multiplication with a constant factor −5.62 m s^-2 (f modes) and −11.1 m s^-2 (p₁ modes), see Appendix B for details.