Updateing documentation (Marian)

diff --git a/TPC/doc/calib/clusterParam/clusterParam.tex b/TPC/doc/calib/clusterParam/clusterParam.tex
index a3071e511ad5af01770956b4992a7af09c05703d..941eeab97bcf5787c01d81a113b1231b8c6aee8d 100644 (file)
--- a/TPC/doc/calib/clusterParam/clusterParam.tex
+++ b/TPC/doc/calib/clusterParam/clusterParam.tex
@@ -699,18 +699,33 @@ In ALICE TPC three different pad gemetries are used.
 The space point resolution was fitted for separatelly for each geometry. The fitted parameters $p_0$ $p_L$ and $p_A$ are shown in the table \ref{table:PointResolFitParam} rescaled with the pad length.\r
 \r
 \r
-\r
 The agreement between  previously mentioned fit and the data is on thel level of the\r
 $\approx10-20\%$. In previous formula we assumed that all of the electrons created in ionization are contibuting to the measured signal. Because of the threshold effect the\r
-part of the signal is cut-off. The fraction of the signal bellow threshold is proportional to the response function witdth and is incresing with drift length and inclination angle. The following correction function are used: \r
+part of the signal is cut-off. The fraction of the signal bellow threshold is proportional to the response function witdth and is incresing with drift length and inclination angle. The following correction functions are used: \r
 \begin{eqnarray}\\r
      \nonumber\\\r
      p_L \approx p_{L0}p_{LC}=p_{L0}(1+p_{L1}L_{\rm{Drift}}+p_{L2}\tan^2\alpha)\r
      \nonumber\\\r
      p_A \approx p_{A0}p_{AC}=p_{A0}(1+p_{A1}L_{\rm{Drift}}+p_{A2}\tan^2\alpha)\r
+\label{eq:PointResolFitCorrection}\r
 \end{eqnarray}\r
 \r
-The measured reolution in Y and Z direction and corresponding fits are shown on picure \ref{figPointResolYDRTAN} and \ref{figPointResolZDRTAN}. The agrement with the data is on the level of about 2\%.\r
+To estimate the number of electrons contibuted to creation of the signal, the cluster charge can be used. Additional correction was tested. Terms proportional to $1/Q$ can be  added to the formula \ref{eq:PointResolFitCorrection}. However the space point resolution is improving only until some limit (see fig.\ref{figPointResolYQ}) determined by the range of the secondary delta electrons. Q dependent \r
+\r
+\begin{figure}\r
+  \centering\epsfig{figure=picClusterResol/QresolY_mag.eps,width=0.7\linewidth}\r
+  \centering\epsfig{figure=picClusterResol/QresolY.eps,width=0.7\linewidth}\r
+ \label{figPointResolYQ} \r
+\caption{Space point resolution in Y direcition as function of deposited charge $Q_{max}$.\r
+Upper part-with magnetic field, lower part without magnetic field. Space point resolution is improving increasing deposited charge $Q_{max}$. Starting from some critical charge the resolution is worsening.  The effect can be explained to be due to the secondary electrons - delta rays. The range of the delta rays is much smaller in presence of the magnetic field.\r
+}\r
+\r
+\end{figure}\r
+\r
+\r
+The measured resolution in Y and Z direction and corresponding fits are shown on picure \ref{figPointResolYDRTAN} and \ref{figPointResolZDRTAN}. The agrement with the data is on the level of about 2\%. \r
+\r
+\r
 \r
 \r
 \begin{figure}\r