Recent hydrodynamic studies of core-collapse supernovae imply that the neutrino-heated ejecta from a nascent neutron star develops to supersonic outflows .
These supersonic winds are influenced by the reverse shock from the preceding supernova ejecta , forming the wind termination shock .
We investigate the effects of the termination shock in neutrino-driven winds and its roll on the r -process .
Supersonic outflows are calculated with a semi-analytic neutrino-driven wind model .
Subsequent termination-shocked , subsonic outflows are obtained by applying the Rankine-Hugoniot relations .
We find a couple of effects that can be relevant for the r -process .
First is the sudden slowdown of the temperature decrease by the wind termination .
Second is the entropy jump by termination-shock heating , up to several 100 N _ { \mathrm { A } } k .
Nucleosynthesis calculations in the obtained winds are performed to examine these effects on the r -process .
We find that 1 ) the slowdown of the temperature decrease plays a decisive roll to determine the r -process abundance curves .
This is due to the strong dependences of the nucleosynthetic path on the temperature during the r -process freezeout phase .
Our results suggest that only the termination-shocked winds with relatively small shock radii ( \sim 500 km ) are relevant for the bulk of the solar r -process abundances ( A \approx 100 - 180 ) .
The heaviest part in the solar r -process curve ( A \approx 180 - 200 ) , however , can be reproduced both in shocked and unshocked winds .
These results may help to constrain the mass range of supernova progenitors relevant for the r -process .
We find , on the other hand , 2 ) negligible roles of the entropy jump on the r -process .
This is a consequence that the sizable entropy increase takes place only at a large shock radius ( \gtrsim 10 , 000 km ) where the r -process has already ceased .