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A spectroscopic and photometric analysis has been carried out for thirty-twocandidate SX_Phe variable blue straggler stars in the Kepler-field (Balona &Nemec 2012). Radial velocities (RVs), space motions (U,V,W), projected rotationvelocities (v sin i), spectral types, and atmospheric characteristics (T_eff,log g, [Fe/H], xi_t, zeta_RT, etc.) are presented for 30 of the 32 stars.Although several stars are metal-weak with extreme halo orbits, the mean [Fe/H]of the sample is near solar, thus the stars are more metal-rich than expectedfor a typical sample of Pop.II stars, and more like halo metal-rich A-typestars (Perry 1969). Two thirds of the stars are fast rotators with v sin i > 50km/s, including four stars with v sin i > 200 km/s. Three of the stars have(negative) RVs > 250 km/s, five have retrograde space motions, and 21 havetotal speeds (relative to the LSR) > 400 km/s. All but one of the 30 stars havepositions in a Toomre diagram consistent with the kinematics of bona fide halostars (the exception being a thick-disk star). Observed Roemer time delays,pulsation frequency modulations and light curves suggest that at least onethird of the stars are in binary (or triple) systems with orbital periodsranging from 2.3 days to more than four years.

Metal-Rich SX Phe stars in the Kepler Field