  From the modeling and simulation results of presupernova evolution of massive
stars, it was found that isotopes of iron, $^{54,55,56}$Fe, play a significant
role inside the stellar cores, primarily decreasing the electron-to-baryon
ratio ($Y_{e}$) mainly via electron capture processes thereby reducing the
pressure support. The neutrinos produced, as a result of these capture
processes, are transparent to the stellar matter and assist in cooling the core
thereby reducing the entropy. The structure of the presupernova star is altered
both by the changes in $Y_{e}$ and the entropy of the core material. Here we
present the microscopic calculation of Gamow-Teller strength distributions for
isotopes of iron. The calculation is also compared with other theoretical
models and experimental data. Presented also are stellar electron capture rates
and associated neutrino cooling rates, due to isotopes of iron, in a form
suitable for simulation and modeling codes. It is hoped that the nuclear inputs
presented here should assist core-collapse simulators in the process of
fine-tuning of the $Y_{e}$ parameter during various phases of presupernova
evolution of massive stars. A reliable and accurate time evolution of this
parameter is a possible key to generate a successful explosion in modeling of
core-collapse supernovae.
