Top: normalized (over 1500 kpc), azimuthally averaged, projected gravitational potential reconstructed from the X-ray (Eq. (9)) and from the SZ signal (Eq. (12)) of Abell 2142 compared to the NFW fit of the lensing data performed by Umetsu et al. (2009). Blue: projected potential reconstructed from the SZ signal; Red: projected potential reconstructed from the X-ray signal; Black: Fit of Umetsu et al. (2009). Bottom: residuals between the potentials reconstructed from the X-ray and SZ signal computed with (f_SZ (s)∕f_XR(s)) and the uncertainties on this quantity are obtained by error propagation. The dashed line represents the case where f_SZ (s) = f_XR(s).