Changeset 6383 for trunk/MagicSoft
- Timestamp:
- 02/11/05 18:30:53 (20 years ago)
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trunk/MagicSoft/TDAS-Extractor/Pedestal.tex
r6382 r6383 120 120 \begin{figure}[htp] 121 121 \centering 122 \vspace{\floatsep}123 122 \includegraphics[width=0.3\linewidth]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38993_RelMean.eps} 124 123 \vspace{\floatsep} … … 138 137 \begin{figure}[htp] 139 138 \centering 140 \vspace{-\floatsep}141 139 \includegraphics[width=0.3\linewidth]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38993_RelMean.eps} 142 140 \vspace{\floatsep} … … 156 154 \begin{figure}[htp] 157 155 \centering 158 \vspace{ -\floatsep}156 \vspace{\floatsep} 159 157 \includegraphics[width=0.3\linewidth]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38993_RelMean.eps} 160 158 \vspace{\floatsep} … … 200 198 \end{description} 201 199 202 Figures~\ref{fig:amp:relmean} through~\ref{fig:df:relmean} 203 show the calculated means obtained with this method for all pixels in the camera 204 and for different levels of night-sky background. 205 One can see that the bias vanishes to an accuracy of better than 1\% 206 for the extractors which are used in this TDAS. 207 208 \par 209 210 The following plots~\ref{fig:sw:distped} through~\ref{fig:amp:relrms} show results 200 \par 201 202 The following figures~\ref{fig:amp:relmean} through~\ref{fig:df:relrms} show results 211 203 obtained with the second method for three background intensities: 212 204 … … 214 206 \item Closed camera and no (Poissonian) fluctuation due to photons from the night sky background 215 207 \item The camera pointing to an extra-galactic region with stars in the field of view 216 \item The camera illuminated by a continuous light source of high intensity causing much higher pedestal 217 fluctuations than in usual observation conditions. 208 \item The camera illuminated by a continuous light source of intensity 100. 218 209 \end{enumerate} 219 210 211 Figures~\ref{fig:amp:relmean} through~\ref{fig:df:relmean} 212 show the calculated biases obtained with this method for all pixels in the camera 213 and for the different levels of (night-sky) background. 214 One can see that the bias vanishes to an accuracy of better than 1\% 215 for the extractors which are used in this TDAS. 216 217 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%1 218 219 \begin{figure}[htp] 220 \centering 221 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38993_RMSDiff.eps} 222 \vspace{\floatsep} 223 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38995_RMSDiff.eps} 224 \vspace{\floatsep} 225 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38996_RMSDiff.eps} 226 \caption{MExtractTimeAndChargeSpline with amplitude: 227 Difference in RMS (per FADC slice) between extraction algorithm 228 applied on a fixed window and the corresponding pedestal RMS. 229 Closed camera (left), open camera observing extra-galactic star field (right) and 230 camera being illuminated by the continuous light (bottom). 231 Every entry corresponds to one pixel.} 232 \label{fig:amp:relrms} 233 \end{figure} 234 235 236 \begin{figure}[htp] 237 \centering 238 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38993_RMSDiff.eps} 239 \vspace{\floatsep} 240 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38995_RMSDiff.eps} 241 \vspace{\floatsep} 242 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38996_RMSDiff.eps} 243 \caption{MExtractTimeAndChargeSpline with integral over 2 slices: 244 Difference in RMS (per FADC slice) between extraction algorithm 245 applied on a fixed window and the corresponding pedestal RMS. 246 Closed camera (left), open camera observing extra-galactic star field (right) and 247 camera being illuminated by the continuous light (bottom). 248 Every entry corresponds to one 249 pixel.} 250 \label{fig:amp:relrms} 251 \end{figure} 252 253 254 \begin{figure}[htp] 255 \centering 256 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38993_RMSDiff.eps} 257 \vspace{\floatsep} 258 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38995_RMSDiff.eps} 259 \vspace{\floatsep} 260 \includegraphics[width=0.47\linewidth]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38996_RMSDiff.eps} 261 \caption{MExtractTimeAndChargeDigitalFilter: 262 Difference in RMS (per FADC slice) between extraction algorithm 263 applied on a fixed window and the corresponding pedestal RMS. 264 Closed camera (left), open camera observing extra-galactic star field (right) and 265 camera being illuminated by the continuous light (bottom). 266 Every entry corresponds to one pixel.} 267 \label{fig:df:relrms} 268 \end{figure} 269 270 271 220 272 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 273 274 Figures~\ref{fig:amp:relrms} through~\ref{fig:amp:relrms} show the 275 differences in $R$ between the calculated pedestal RMS and 276 the one obtained by applying the extractor, converted to equivalent photo-electrons. One entry 277 corresponds to one pixel of the camera. 278 The distributions have a negative mean in the case of the digital filter showing the 279 ``filter'' capacity of that algorithm. It ``filters out'' between 0.12 photo-electrons night sky 280 background for the extra-galactic star-field until 0.2 photo-electrons for the continuous light. 281 282 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 283 284 285 \subsubsection{ \label{sec:determiner} Application of the Signal Extractor to a Sliding Window 286 of Pedestal Events} 287 288 By applying the signal extractor to a global extraction window of pedestal events, allowing 289 it to ``slide'' and maximize the encountered signal, we 290 determine the bias $B$ and the mean-squared error $MSE$ for the case of no signal ($S=0$). 291 \par 292 In MARS, this functionality is implemented with a function-call to: \\ 293 294 {\textit{\bf MJPedestal::SetExtractionWithExtractor()}} \\ 295 296 \par 297 298 Figures~\ref{fig:amp:distped} through~\ref{fig:df:distped} show the 299 extracted pedestal distributions for the digital filter with cosmics weights (extractor~\#28) and the 300 spline amplitude (extractor~\#27), respectively for one examplary channel (corresponding to pixel 200). 301 One can see the (asymmetric) Poisson behaviour of the 302 night sky background photons for the distributions with open camera and the cutoff at the lower egde 303 for the distribution with high-intensity continuous light due to a limited pedestal offset and the cutoff 304 to negative fluctuations. 305 \par 221 306 222 307 \begin{figure}[htp] … … 286 371 \end{figure} 287 372 288 289 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 290 291 292 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%1 293 294 \begin{figure}[htp] 295 \centering 296 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38993_RMSDiff.eps} 297 \vspace{\floatsep} 298 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38995_RMSDiff.eps} 299 \vspace{\floatsep} 300 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Amplitude_Amplitude_Range_01_09_01_10_Run_38996_RMSDiff.eps} 301 \caption{MExtractTimeAndChargeSpline with amplitude: 302 Difference in pedestal RMS (per FADC slice) between extraction algorithm 303 applied on a fixed window of 1 FADC slice (``extractor random'') and a simple addition of 304 2 FADC slices (``fundamental''). On the top, a run with closed camera has been taken, in the center 305 an opened camera observing an extra-galactic star field and on the bottom, an open camera being 306 illuminated by the continuous light of the calibration (level: 100). Every entry corresponds to one 307 pixel.} 308 \label{fig:amp:relrms} 309 \end{figure} 310 311 312 \begin{figure}[htp] 313 \centering 314 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38993_RMSDiff.eps} 315 \vspace{\floatsep} 316 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38995_RMSDiff.eps} 317 \vspace{\floatsep} 318 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeSpline_Rise-and-Fall-Time_0.5_1.5_Range_01_10_02_12_Run_38996_RMSDiff.eps} 319 \caption{MExtractTimeAndChargeSpline with integral over 2 slices: 320 Difference in pedestal RMS (per FADC slice) between extraction algorithm 321 applied on a fixed window of 2 FADC slices (``extractor random'') and a simple addition of 322 2 FADC slices (``fundamental''). On the top, a run with closed camera has been taken, in the center 323 an opened camera observing an extra-galactic star field and on the bottom, an open camera being 324 illuminated by the continuous light of the calibration (level: 100). Every entry corresponds to one 325 pixel.} 326 \label{fig:amp:relrms} 327 \end{figure} 328 329 330 \begin{figure}[htp] 331 \centering 332 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38993_RMSDiff.eps} 333 \vspace{\floatsep} 334 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38995_RMSDiff.eps} 335 \vspace{\floatsep} 336 \includegraphics[height=0.3\textheight]{MExtractTimeAndChargeDigitalFilter_Weights_cosmics_weights.dat_Range_01_14_02_14_Run_38996_RMSDiff.eps} 337 \caption{MExtractTimeAndChargeDigitalFilter: 338 Difference in pedestal RMS (per FADC slice) between extraction algorithm 339 applied on a fixed window of 6 FADC slices and time-randomized weights (``extractor random'') 340 and a simple addition of 6 FADC slices (``fundamental''). On the top, a run with closed camera 341 has been taken, in the center 342 an opened camera observing an extra-galactic star field and on the bottom, an open camera being 343 illuminated by the continuous light of the calibration (level: 100). Every entry corresponds to one 344 pixel.} 345 \label{fig:df:relrms} 346 \end{figure} 347 348 349 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 350 351 Figures~\ref{fig:df:distped},~\ref{fig:amp:distped} 352 and~\ref{fig:amp:distped} show the 353 extracted pedestal distributions for the digital filter with cosmics weights (extractor~\#28) and the 354 spline amplitude (extractor~\#27), respectively for one examplary channel (corresponding to pixel 200). 355 One can see the (asymmetric) Poisson behaviour of the 356 night sky background photons for the distributions with open camera and the cutoff at the lower egde 357 for the distribution with high-intensity continuous light due to a limited pedestal offset and the cutoff 358 to negative fluctuations. 359 \par 360 Figures~\ref{fig:df:relmean} 361 and~\ref{fig:amp:relmean} show the 362 relative difference between the calculated pedestal mean and 363 the one obtained by applying the extractor for 364 all channels of the MAGIC camera. One can see that in all cases, the distribution is centered around zero, 365 while its width is never larger than 0.01 which corresponds about to the precision of the extracted mean for 366 the number of used events. (A very similar distribution is obtained by comparing the results 367 of the same pedestal calculator applied to different ranges of FADC slices.) 368 \par 369 Figures~\ref{fig:df:relrms} 370 and~\ref{fig:amp:relrms} show the 371 relative difference between the calculated pedestal RMS, normalized to an equivalent number of slices 372 (2.5 for the digital filter and 1. for the amplitude of the spline) and 373 the one obtained by applying the extractor for all channels of the MAGIC camera. 374 One can see that in all cases, the distribution is not centered around zero, but shows an offset depending 375 on the light intensity. The difference can be 10\% in the case of the digital filter and even 25\% for the 376 spline. This big difference for the spline is partly explained by the fact that the pedestals have to be 377 calculated from an even number of slices to account for the clock-noise. However, the (normalized) pedestal 378 RMS depends critically on the number of summed FADC slices, especially at very low numbers. In general, 379 the higher the number of summed FADC slices, the higher the (to the square root of the number of slices) 380 normalized pedestal RMS. 381 382 383 \subsubsection{ \label{sec:determiner} Application of the Signal Extractor to a Sliding Window 384 of Pedestal Events} 385 386 In this section, we apply the signal extractor to a sliding window of pedestal events. 387 \par 388 In MARS, this possibility can be used with a call to 389 {\textit{\bf MJPedestal::SetExtractionWithExtractor()}}. 390 \par 373 \par 374 391 375 Because the background is determined by the single photo-electrons from the night-sky background, 392 376 the following possibilities can occur:
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