  The formation mechanism for blue hook (BHk) stars in globular clusters (GCs)
is still unclear. Following one of the possible scenario, named late hot flash
scenario, we proposed that tidally enhanced stellar wind in binary evolution
may provide the huge mass loss on the red giant branch (RGB) and produce BHk
stars. Employing the detailed stellar evolution code, Modules for Experiments
in Stellar Astrophysics (MESA), we investigated the contributions of tidally
enhanced stellar wind as a possible formation channel for BHk stars in GCs. We
evolved the primary stars with different initial orbital periods using the
binary module in MESA (version 6208) from zero age main-sequence (ZAMS) to post
horizontal branch (HB) stage, and obtained their evolution parameters which are
compared with the observation. The results are consistent with observation in
the color-magnitude diagram (CMD) and the logg-Teff plane for NGC 2808, which
is an example GC hosting BHk stars. However, the helium abundance in the
surface for our models is higher than the one obtained in BHk stars. This
discrepancy between our models and observation is possibly due to the fact that
gravitational settling and radiative levitation which are common processes in
hot HB stars are not considered in the models as well as the fact that the
flash mixing efficiency may be overestimated in the calculations. Our results
suggested that tidally enhanced stellar wind in binary evolution is able to
naturally provide the huge mass loss on the RGB needed for late hot flash
scenario and it is a possible and reasonable formation channel for BHk stars in
GCs.
