\begin{table}%t1 \caption{\label{observations}Basic data of the observations of RR~Lyr.} \small%\centering \par {\begin{tabular}{lccccc} \hline \hline\noalign{\smallskip} Spectrum ID & HJD $-$ & Pulsational & Blazhko & SNR per & Exposure \\ number\tablefoottext{a} & 2453000 & phase & phase & pixel\tablefoottext{b} & time (s) \\ \hline 087 & 183.7953 & 0.173 & 0.280 & 293 & 960.000 \\ 088 & 183.8147 & 0.207 & 0.281 & 250 & 960.000 \\ 089 & 183.8271 & 0.229 & 0.281 & 172 & 960.000 \\ 091 & 183.8441 & 0.260 & 0.281 & 149 & 960.000 \\ 119 & 184.7293 & 0.820 & 0.304 & 215 & 960.000 \\ 120 & 184.7434 & 0.846 & 0.305 & 253 & 960.000 \\ 121 & 184.7559 & 0.868 & 0.305 & 271 & 960.000 \\ 122 & 184.7683 & 0.890 & 0.305 & 194 & 960.000 \\ 124 & 184.7865 & 0.922 & 0.306 & 162 & 960.000 \\ 125 & 184.7988 & 0.943 & 0.306 & 126 & 960.000 \\ 126 & 184.8121 & 0.967 & 0.306 & 63 & 960.000 \\ 158 & 185.7401 & 0.604 & 0.330 & 101 & 960.000 \\ 159 & 185.7523 & 0.626 & 0.331 & 126 & 960.000 \\ 160 & 185.7645 & 0.647 & 0.331 & 171 & 960.000 \\ 161 & 185.7768 & 0.669 & 0.331 & 233 & 960.000 \\ 163 & 185.7937 & 0.698 & 0.332 & 232 & 960.000 \\ 164 & 185.8059 & 0.720 & 0.332 & 259 & 960.000 \\ 165 & 185.8182 & 0.741 & 0.332 & 113 & 960.000 \\ 166 & 185.8304 & 0.763 & 0.333 & 210 & 960.000 \\ 168 & 185.8465 & 0.792 & 0.333 & 228 & 960.000 \\ 169 & 185.8587 & 0.814 & 0.333 & 290 & 960.000 \\ 170 & 185.8709 & 0.834 & 0.334 & 236 & 960.000 \\ 171 & 185.8831 & 0.856 & 0.334 & 216 & 960.000 \\ 173 & 185.8989 & 0.885 & 0.334 & 236 & 960.000 \\ 174 & 185.9112 & 0.905 & 0.335 & 215 & 960.000 \\ 175 & 185.9234 & 0.928 & 0.335 & 233 & 960.000 \\ 176 & 185.9356 & 0.948 & 0.335 & 290 & 960.000 \\ 178 & 185.9512 & 0.977 & 0.336 & 357 & 960.000 \\ 204 & 186.7293 & 0.349 & 0.356 & 190 & 960.000 \\ 205 & 186.7425 & 0.372 & 0.356 & 138 & 960.000 \\ 206 & 186.7548 & 0.394 & 0.356 & 203 & 960.000 \\ 207 & 186.7670 & 0.416 & 0.357 & 46 & 960.000 \\ 209 & 186.7876 & 0.452 & 0.357 & 131 & 960.000 \\ 210 & 186.8007 & 0.475 & 0.358 & 77 & 960.000 \\ 251 & 187.7208 & 0.098 & 0.381 & 359 & 960.000 \\ 252 & 187.7330 & 0.120 & 0.382 & 319 & 960.000 \\ 253 & 187.7442 & 0.141 & 0.382 & 120 & 769.397 \\ 255 & 187.7632 & 0.173 & 0.382 & 124 & 960.000 \\ 256 & 187.7803 & 0.203 & 0.383 & 160 & 960.000 \\ 257 & 187.7923 & 0.226 & 0.383 & 87 & 797.949 \\ 258 & 187.8060 & 0.249 & 0.383 & 272 & 960.000 \\ {\bf 260} & 187.8226 & 0.278 & 0.384 & 322 & 960.000 \\ 261 & 187.8370 & 0.303 & 0.384 & 214 & 960.000 \\ 262 & 187.8504 & 0.327 & 0.385 & 288 & 960.000 \\ 263 & 187.8634 & 0.349 & 0.385 & 216 & 960.000 \\ 319 & 243.6989 & 0.854 & 1.824 & 27 & 960.000 \\ 322 & 243.7688 & 0.976 & 1.826 & 21 & 960.000 \\ 323 & 243.7832 & 0.002 & 1.826 & 18 & 960.000 \\ 324 & 243.7955 & 0.024 & 1.827 & 18 & 960.000 \\ 326 & 243.8123 & 0.053 & 1.827 & 21 & 960.000 \\ 327 & 243.8262 & 0.078 & 1.827 & 25 & 960.000 \\ 328 & 243.8395 & 0.101 & 1.828 & 13 & 960.000 \\ 363 & 244.6062 & 0.454 & 1.847 & 231 & 960.000 \\ 364 & 244.6201 & 0.478 & 1.848 & 251 & 960.000 \\ 365 & 244.6323 & 0.500 & 1.848 & 258 & 960.000 \\ 366 & 244.6445 & 0.521 & 1.848 & 238 & 960.000 \\ 368 & 244.6622 & 0.553 & 1.849 & 249 & 960.000 \\ 369 & 244.6744 & 0.574 & 1.849 & 181 & 960.000 \\ 370 & 244.6870 & 0.596 & 1.849 & 173 & 960.000 \\ 371 & 244.6992 & 0.618 & 1.850 & 171 & 960.000 \\ 373 & 244.7168 & 0.648 & 1.850 & 152 & 960.000 \\ 374 & 244.7290 & 0.670 & 1.851 & 122 & 960.000 \\ 375 & 244.7412 & 0.693 & 1.851 & 90 & 960.000 \\ 376 & 244.7535 & 0.713 & 1.851 & 69 & 960.000 \\ \hline \end{tabular}} \tablefoot{\tablefootmark{a}{The spectra number 253 and 257 have a lower exposure time, because the observation was stopped due to the presence of thick clouds. Spectrum number {\bf 260} is the one analyzed in detail in this paper.} \tablefootmark{b}{Calculated at $\sim$5000~\AA.}} \end{table}