Changeset 5596

Timestamp:

12/14/04 21:01:07 (20 years ago)

Author:

hbartko

Message:

*** empty log message ***

Location:

trunk/MagicSoft/TDAS-Extractor

Files:

• Changelog (modified) (1 diff)
• Introduction.tex (modified) (1 diff)
• Reconstruction.tex (modified) (3 diffs)
• bibfile.bib (modified) (1 diff)
• pulpo_shape_high_low_MC_TDAS.eps (added)
• pulpo_shape_high_low_TDAS.eps (added)
• shape_green_UV_data_TDAS.eps (added)

trunk/MagicSoft/TDAS-Extractor/Changelog

@@ -19 +19 @@
 
                                                  -*-*- END OF LINE -*-*-
+
+2004/12/14: Hendrik Bartko
+  * Introduction.tex: wrote some introduction, including
+                      new figure Magic_readout_scheme1.eps
+  * Reconstruction.tes: wrote something about the pulse reconstruction
+                        new figures: pulpo_shape_high_low_TDAS.eps
+                                     pulpo_shape_high_low_MC_TDAS.eps
+                                     shape_green_UV_data_TDAS.eps 
+  * bibfile.bib: included two more references about optical link and
+                 PMTs
+
 2004/12/08: Markus Gaug 
   * Algorithms.tex: - changed order of 'spline' extractors to go in 

trunk/MagicSoft/TDAS-Extractor/Introduction.tex

@@ -5 +5 @@
 \end{itemize}
 
+The MAGIC read-out scheme, including the PMT camera, the analog-optical link, the majority trigger logic and FADCs, is schematically shown in figure \ref{fig:MAGIC_read-out_scheme}. The used PMTs provide a very fast response to the input light signal. The response of the PMTs to sub-ns input light pulses shows a FWHM of 1.0 - 1.2 ns and rise and fall times of 600 and 700 ps correspondingly \cite{Magic-PMT}. By modulating VCSEL type laser diodes in amplitude the ultra fast analogue signals from the PMTs are transferred via 162m long, 50/125 $\mu$m diameter optical fibers to the counting house \cite{MAGIC-analog-link-2}. After transforming the light back to an electrical signal, the original PMT pulse has a FWHM of about 2.2 ns and rise and fall times of about 1ns. % was 2.2 ns
+
+%an analog optical link \ci
+te{MAGIC-analog-link-2} to the counting house.
+
+
+\begin{figure}[h!]
+\begin{center}
+\includegraphics[width=\textwidth]{Magic_readout_scheme1.eps}
+\end{center}
+\caption[Current MAGIC read-out scheme.]{Current MAGIC read-out scheme: the analog PMT signals are transferred via an analog optical link to the counting house where after the trigger decision the signals are digitized by using a 300 MHz FADCs system and written to the hard disk of a DAQ PC.} \label{fig:MAGIC_read-out_scheme}
+\end{figure}
+
+ 
+
+%After modulating VCSEL type laser diodes, after traveling through 162m of multi-mode graded index fiber of 50/125 $\mu$m diameter and.
+
+
+In order to sample this pulse shape with the used 300 MSamples/s FADC system, the pulse is stretched to a FWHM $>6$ ns (the original pulse is folded with a stretching function of 6ns). Obviously by doing this, more LONS is integrated and thus the performance of the telescope on the analysis level is degraded. 
+
+Because the current MAGIC FADCs have a resolution of 8 bit only, the signals are split into two branches with different gains by a factor of 10. One branch is delayed by 50 ns and then both branches are multiplexed and consecutively read-out by one FADC. % The maximum sustained trigger rate could be 1 kHz. The FADCs feature a FIFO memory which allows a significantly higher short-time rate.
+
 
 %%% Local Variables: 

trunk/MagicSoft/TDAS-Extractor/Reconstruction.tex

@@ -14 +14 @@
 \begin{figure}[h!]
 \begin{center}
-\includegraphics[totalheight=7cm]{pulpo_shape_high.eps}
+\includegraphics[totalheight=7cm]{pulpo_shape_high_low_TDAS.eps}%{pulpo_shape_high.eps}
 \end{center}
 \caption[Reconstructed high gain shape.]{Average reconstructed high gain pulse shape from a pulpo run. The FWHM is about 6.2 ns.} \label{fig:pulpo_shape_high}
@@ -21 +21 @@
 \begin{figure}[h!]
 \begin{center}
-\includegraphics[totalheight=7cm]{pulpo_shape_low.eps}
+\includegraphics[totalheight=7cm]{pulpo_shape_high_low_MC_TDAS.eps}%{pulpo_shape_low.eps}
 \end{center}
-\caption[Reconstructed pulpo low gain shape.]{Average reconstructed high gain pulse shape from a pulpo run. The FWHM is about 10 ns.} \label{fig:pulpo_shape_low}
+\caption[Reconstructed pulpo low gain shape.]{Average normalized reconstructed high gain and low gain pulse shapes from a pulpo run. The FWHM of the low gain pulse is about 10 ns. The black line corresponds to the pulse shape implemented into the MC simulations.} \label{fig:pulpo_shape_low}
 \end{figure}
 
@@ -31 +31 @@
 \begin{figure}[h!]
 \begin{center}
-\includegraphics[totalheight=7cm]{shape_green_high.eps}
+\includegraphics[totalheight=7cm]{shape_green_UV_data_TDAS.eps}%{shape_green_high.eps}
 \end{center}
 \caption[Reconstructed green calibration high gain shape.]{Average reconstructed high gain pulse shape for one green LED calibration run. The FWHM is about 6.5 ns.} \label{fig:shape_green_high}

trunk/MagicSoft/TDAS-Extractor/bibfile.bib

@@ +1 @@
+@Article{Magic-PMT,
+     author    = "Ostankov, A. and Paneque, D. and Martinez, M. and Lorenz,
+                  E. and Mirzoian, R.",
+     title     = "A study of the new hemispherical 6-dynodes PMT from
+                  electron tubes",
+     journal   = "Nucl. Instrum. Meth.",
+     volume    = "A442",
+     year      = "2000",
+     pages     = "117-123",
+     SLACcitation  = "%%CITATION = NUIMA,A442,117;%%"
+}
+
+
+@Article{MAGIC-analog-link-2,
+     author    = "Lorenz, E. and Maier, R. and Tran, T. S. and Weissbach, P.
+                  ",
+     title     = "A fast, large dynamic range analog signal transfer system
+                  based on optical fibers",
+     journal   = "Nucl. Instrum. Meth.",
+     volume    = "A461",
+     year      = "2001",
+     pages     = "517-520",
+     SLACcitation  = "%%CITATION = NUIMA,A461,517;%%"
+}
+
+
 @ARTICLE{OF94,
    author = "Cleland, W. E. and Stern, E. G.",