  We use high resolution ARPES to study the resonant, collective excitation
mode in the superconducting state of Bi2212. By collecting very high quality
data we found new features in the self energy in the antinodal region, where
the interaction of electrons with the mode is the strongest. This interaction
leads to pronounced peak in the scattering rate and we demonstrate that this
feature is directly responsible for well known hump-dip-peak structure in
cuprates. By studying how the weight of this peak changes with temperature we
unequivocally demonstrate that interaction of electrons with resonant mode in
cuprates vanishes at Tc and is very much localized in the momentum space close
to the antinode. These findings present a consistent picture of line shape and
self energy signatures of the electron-boson coupling in cuprates and resolve
long standing controversy surrounding this issue. The momentum dependence of
the strength of electron-mode interaction enables development of quantitative
theory of this phenomenon in cuprates.
