If Gamma Dor-type pulsations are driven by the convective blocking mechanism, a convective envelope at a sufficient depth is essential. There are several hot Gamma Dor and hybrid star candidates in which there should not be an adequate convective envelope to excite the{gamma}Dor-type oscillations. The existence of these hot objects needs an explanation. Therefore, we selected, observed and studied 24 hot{gamma}Dor and hybrid candidates to investigate their properties. The atmospheric parameters, chemical abundances and vsini values of the candidates were obtained using medium-resolution (R= 46 000)spectra taken with the FIES instrument mounted at the NordicOptical Telescope. We also carried out frequency analyses of theKeplerlong- and short-cadence data to determine the exact pulsation contents. We found only five bona-fide hot{gamma}Dor and three bona-fide hot hybrid stars in our sample. The other 16 stars were found to benormal{gamma}Dor,{delta}Sct, or hybrid variables. No chemical peculiarity was detected in the spectra of the bona-fide hot{gamma}Dor and hybrid stars. We investigated the interplay between rotation and pulsational modes. We also found that the hot{gamma}Dor stars havehigherGaialuminosities and larger radii compared to main-sequence A-F stars.
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