Atmospheric parameters of single-exposure spectra obtained by template-matching for SDSS J134134.54+281855.2 with 12 exposures, which is a member star of globular cluster NGC 5272. Panel (a) shows the effective temperature varies with phase. Panel (b) shows the log g varies with phase. Panel (c) shows the measurement of metallicity at different phases; the dashed line shows the reference metallicity given by Harris (2010). Panel (d) shows the equivalent width of the Ca II K line EW(Ca II K) at different phases. In Panel (d), the plus symbols represent the calculated values of EW(Ca II K) from 12 single-exposure spectra and the diamond symbols indicate the minimal value of EW(Ca II K) of model spectra with the same ﹩{T}_{\mathrm{eff}}﹩ as that from observed single-exposure spectra (estimated by the first round of fitting; see Section 3.1 for details).