Index: trunk/MagicSoft/TDAS-Extractor/Algorithms.tex =================================================================== --- trunk/MagicSoft/TDAS-Extractor/Algorithms.tex (revision 6646) +++ trunk/MagicSoft/TDAS-Extractor/Algorithms.tex (revision 6647) @@ -6,5 +6,5 @@ There, the base classes {\textit{\bf MExtractor}}, {\textit{\bf MExtractTime}}, {\textit{\bf MExtractTimeAndCharge}} and all individual extractors can be found. Figure~\ref{fig:extractorclasses} gives a sketch of the -inheritances of each class and what each class calculates. +inheritances and tasks of each class. \begin{figure}[htp] @@ -17,19 +17,19 @@ The following base classes for the extractor tasks are used: \begin{description} -\item[MExtractor:\xspace] This class provides the basic data members equal for all extractors which are: +\item[MExtractor:\xspace] This class provides the basic data members, equal for all extractors, which are: \begin{enumerate} - \item Global extraction ranges, parameterized by the variables + \item Global extraction ranges, defined by the variables {\textit{\bf fHiGainFirst, fHiGainLast, fLoGainFirst, fLoGainLast}} and the function {\textit{\bf SetRange()}}. The ranges always {\textit{\bf include}} the edge slices. \item An internal variable {\textit{\bf fHiLoLast}} regulating the overlap of the desired high-gain extraction range into the low-gain array. - \item The maximum possible FADC value, before the slice is declared as saturated, parameterized + \item The maximum possible FADC value, before the slice is declared as saturated, defined by the variable {\textit{\bf fSaturationLimit}} (default:\,254). \item The typical delay between high-gain and low-gain slices, expressed in FADC slices and parameterized by the variable {\textit{\bf fOffsetLoGain}} (default:\,1.51) - \item Pointers to the used storage containers {\textit{\bf MRawEvtData, MRawRunHeader, MPedestalCam}} - and~{\textit{\bf MExtractedSignalCam}}, parameterized by the variables + \item Pointers to the storage containers {\textit{\bf MRawEvtData, MRawRunHeader, MPedestalCam}} + and~{\textit{\bf MExtractedSignalCam}}, defined by the variables {\textit{\bf fRawEvt, fRunHeader, fPedestals}} and~{\textit{\bf fSignals}}. - \item Names of the used storage containers to be searched for in the parameter list, parameterized + \item Names of the storage containers to be searched for in the parameter list, parameterized by the variables {\textit{\bf fNamePedestalCam}} and~{\textit{\bf fNameSignalCam}} (default: ``MPedestalCam'' and~''MExtractedSignalCam''). @@ -56,10 +56,10 @@ \item[MExtractTime:\xspace] This class provides - additionally to those already declared in {\textit{\bf MExtractor}} - - the basic data members equal for all time extractors which are: + the basic data members, equal for all time extractors, which are: \begin{enumerate} - \item Pointer to the used storage container {\textit{\bf MArrivalTimeCam}} - parameterized by the variables + \item Pointer to the storage container {\textit{\bf MArrivalTimeCam}} + parameterized by the variable {\textit{\bf fArrTime}}. - \item The name of the used ``MArrivalTimeCam''-container to be searched for in the parameter list, + \item The name of the ``MArrivalTimeCam''-container to be searched for in the parameter list, parameterized by the variables {\textit{\bf fNameTimeCam}} (default: ``MArrivalTimeCam'' ). \end{enumerate} @@ -82,5 +82,5 @@ \item[MExtractTimeAndCharge:\xspace] This class provides - additionally to those already declared in {\textit{\bf MExtractor}} and {\textit{\bf MExtractTime}} - - the basic data members equal for all time and charge extractors which are: + the basic data members, equal for all time and charge extractors, which are: \begin{enumerate} \item The actual extraction window sizes, parameterized by the variables @@ -118,5 +118,5 @@ The pure signal extractors have in common that they reconstruct only the -charge, but not the arrival time. All treated extractors here derive from the MARS-base +charge, but not the arrival time. All extractors treated here derive from the MARS-base class {\textit{\bf MExtractor}} which provides the following facilities: @@ -133,5 +133,5 @@ As the pulses jitter by about one FADC slice, -not every pulse lies exactly within the optimal limits, especially if one takes small +not every pulse lies exactly within the optimal limits, especially if one chooses small extraction windows. Moreover, the readout position with respect to the trigger position has changed a couple @@ -144,6 +144,6 @@ It simply adds the FADC slice contents in the assigned ranges. As it does not correct for the clock-noise, only an even number of samples is allowed. -Figure~\ref{fig:fixedwindowsketch} gives a sketch of the used extraction ranges for this -paper and two typical calibration pulses. +Figure~\ref{fig:fixedwindowsketch} gives a sketch of the extraction ranges used in this +paper and for two typical calibration pulses. \begin{figure}[htp] @@ -164,6 +164,6 @@ spline interpolated FADC slice values from a fixed extraction range. The edge slices are counted as half. As it does not correct for the clock-noise, only an odd number of samples is allowed. -Figure~\ref{fig:fixedwindowsplinesketch} gives a sketch of the used extraction ranges for this -paper and two typical calibration pulses. +Figure~\ref{fig:fixedwindowsplinesketch} gives a sketch of the extraction ranges used in this +paper and for typical calibration pulses. \begin{figure}[htp] @@ -182,12 +182,11 @@ The basic idea of this extractor is to correct for coherent movements in arrival time for all pixels, as e.g. caused by the trigger jitter. -In a first loop, it fixes a reference point defined as the highest sum of +In a first loop over the pixels, it determined a reference point slices number defined by the highest sum of consecutive non-saturating FADC slices in a (smaller) peak-search window. \par In a second loop over the pixels, -it adds the FADC contents starting from a pre-defined offset from the obtained peak-search window -over an extraction window of a pre-defined window size. +it adds the contents of the FADC slices starting from the reference point over an extraction window of a pre-defined window size. It loops twice over all pixels in every event, because it has to find the reference point, first. -As it does not correct for the clock-noise, only an even number of samples is allowed. +As it does not correct for the clock-noise, only extraction windows with an even number of samples are allowed. For a high intensity calibration run causing high-gain saturation in the whole camera, this extractor apparently fails since only dead pixels are taken into account in the peak search @@ -221,7 +220,8 @@ \subsection{Combined Extractors} -The combined extractors have in common that they reconstruct the arrival time and -the charge at the same time and for the same pulse. -All treated combined extractors here derive from the MARS-base +The combined extractors have in common that for a given pulse, they reconstruct +both the arrival time and +the charge. +All combined extractors described here derive from the MARS-base class {\textit{\bf MExtractTimeAndCharge}} which itself derives from MExtractor and MExtractTime. It provides the following facilities: @@ -230,7 +230,6 @@ \item Only one loop over all pixels is performed. \item The individual FADC slice values get the clock-noise-corrected pedestals immediately subtracted. -\item The low-gain extraction range is adapted dynamically, based on the computed arrival time - from the high-gain samples. -\item Extracted times from the low-gain samples get corrected for the intrinsic time delay of the low-gain +\item The low-gain extraction range is adapted dynamically, based on the arrival time computed from the high-gain samples. +\item Arrival times extracted from the low-gain samples get corrected for the intrinsic time delay of the low-gain pulse. \item The global extraction limits can be set from outside. @@ -265,8 +264,8 @@ \begin{equation} - t = \frac{\sum_{i=i_0}^{i_0+ws} s_i \cdot i}{\sum_{i=i_0}^{i_0+ws} i} -\end{equation} -where $i$ denotes the FADC slice index, starting from $i_0$ -window and running over a window of size $ws$. $s_i$ the clock-noise and + t = \frac{\sum_{i=i_0}^{i_0+\mathrm{\it ws}-1} s_i \cdot i}{\sum_{i=i_0}^{i_0+\mathrm{\it ws}-1} i} +\end{equation} +where $i$ denotes the FADC slice index, starting from slice $i_0$ +and running over a window of size $\mathrm{\it ws}$. $s_i$ the clock-noise and pedestal-corrected FADC slice contents at slice position $i$. \par @@ -296,6 +295,5 @@ \begin{description} \item[Extraction Type Amplitude:\xspace] The amplitude of the spline maximum is taken as charge signal -and the (precise) position of the maximum is returned as arrival time. This type is faster, since it -performs not spline integration. +and the (precise) position of the maximum is returned as arrival time. This type is faster, since a spline integration is not performed. \item[Extraction Type Integral:\xspace] The integrated spline between maximum position minus rise time (default: 1.5 slices) and maximum position plus fall time (default: 4.5 slices)