GEOMETRY
	Both FTPC East and West are symmetric from the interaction center. It is a gas tube of 119 cm 
lenght. Taken the interaction point as the coordinates origin the tube goes from 150 cm to 269 cm.
To construct the east (negative Z) and the west (positive Z) chamber just changes the z dimensions 
from plus to minus 
The Inner radius = 7.73 cm
The Outer Radius =  30.05 cm
	Each chamber has 10 Padrows where the signals are read. They are arrange in groups of two 
nearbys Padrows. 
The Z positions are:
ZposPadRow1 = 162.75 cm
ZposPadRow2 = 171.25 cm
ZposPadRow3 = 184.05 cm
ZposPadRow4 = 192.55 cm
ZposPadRow5 = 205.35 cm
ZposPadRow6 = 213.85 cm
ZposPadRow7 = 226.65 cm
ZposPadRow8 = 235.15 cm
ZposPadRow9 = 247.95 cm
ZposPadRow10 = 256.45 cm
One more time to construct the east and the west chamber just changes the z dimensions from plus to 
minus.
	The Padrows are divided in the phi angle into six sectors with a small intersection in between. 
Starting from the top the angles would be 
  Sector1 [0.05, 59.05] degrees in phi
  Sector2 [60.05, 119.05] degrees in phi
  Sector3 [120.05, 179.05] degrees in phi
  Sector4 [180.05, 239.05] degrees in phi
  Sector5 [240.05, 299.05] degrees in phi
  Sector6 [300.05, 359.05] degrees in phi
  
	I think that for the material simulation the best thing is create sectors (with a region in phi) 
of gas within the corresponded padrow in the middle.
That would mean...
6 sectors in phi with the z dimension [150, 167] cm
6 sectors in phi with the z dimension [167, 177.65] cm
6 sectors in phi with the z dimension [177.65, 188.3] cm
6 sectors in phi with the z dimension [188.3, 198.95] cm
6 sectors in phi with the z dimension [198.95, 209.6] cm
6 sectors in phi with the z dimension [209.6, 220.25] cm
6 sectors in phi with the z dimension [220.25, 230.9] cm
6 sectors in phi with the z dimension [230.9, 241.55] cm
6 sectors in phi with the z dimension [241.55, 252.2] cm
6 sectors in phi with the z dimension [252.2, 269] cm

	Other thing that could be important is the material between the interaction point and the outer 
part of the chambers. There is a small kapton (mylar) cover to close the gas inside the chamber and 17 
Rings as field-end Caps in aluminium. Symmetrically these Kapton covers and end Caps exist in the outer 
part of the chamber but there are not important for the tracker. 
	The kapton cover is a tube with a innerradius =  7.55 cm and outer radius 30.5 cm
the lenght is 0.02 cm and the z position is 150.04 cm
	The 17 Ring as field-end caps can be represented for small tubes and the z position  155.5 cm 
with an aluminum lenght of 0.06 cm. The respectif inner and auter radius are the following:
	
    Rmin = 8.05+i*1.252778 -0.5 ; 
    Rmax = 8.05+i*1.252778 +0.5 ;
with i = (0,1,2,...,17)

I attach a macro for ROOT with the geometry (FTPCGeometry.C)



MATERIALS 
Aluminium A= 26.980  , Z = 13.0000 Density = 2.700  Radiat Leng = 8.900 (GEANT Standart Number 9) 
Mylar  A= 12.875  , Z = 6.458 Density =1.390  Radiat Leng = 28.5 
Argon Gas (in fact is Argon Co2 50% 50% but the density is almost the same...) 
A= 18 , Z = 39.95 Density =1.78e-3*(273.0/293.0) Radiat Leng = 14.*1.4/%Density (defined like this!) 

Hope this helps,

Maria