ENDCAP WEIGHTS AND MATERIALS
           ----------------------------

 Updated by Dave Cockerill
 19.5.99

 EE Crystals
 30x30 mm**2 at rear, 28.62x28.62 mm**2 at front
 220 mm long, volume 189 cm**3
 Density 8.28 g/cc, weight 1.565 kg
 Each Endcap has 8000 crystals
                   crystal volume              1.512 m3
                   crystal density             8.28  g/cc
                   crystal mass per endcap    12.52  tons
		   crystal mass per Dee	       6.25  tons
                        

                    Weight     Item
                    ---------  ------------------------------------------
                    12,500 Kg  Crystals alone

                     0,350 Kg  Aluminium inserts etc in supercrystals

                     1,200 Kg  Back support plate (5 cm aluminium, from an
                               inner radius of 375 mm to an outer radius of
                               1700 mm, sited 220 mm from the HCAL)
                     
              approx 0,500 Kg  Moderators between back support plate and HCAL
                               from configuration 6, fig 5, CMS TN
                               96-057, see apendix 1.


                       +       weight of FPU/ADC Electronics and its cooling,
                               which is currently unknown for  weight and
                               density. This will be sited on the 'HCAL side'
                               of the ECAL back support plate.    
                       +       weight of aluminium seating elements
                       +       environmental shield
                       +       outer annulus support

                    ---------
 Xtal Endcap total  14,550 Kg  plus +, NO preshower 
                    ---------

 Dee Total           7,275 Kg  plus + and lifting frames etc, NO preshower
                                                                   


 Completed Xtal + Preshower endcap
 ---------------------------------

                    14,650 Kg  Xtal Endcap

                     1,852 Kg  Preshower (latest info from P Wertelaers, see
                               appendix 2)
                    ---------
 Endcap total       16,502 Kg  plus +
                    ---------


         
Appendix 1 Moderator behind endcap xtals
*******************************************             

 From Huhtinens 'configuration 6' 
** and new calculations for the cylindrical moderator (march 1999)

 a cylindrical moderator behind the 'plug'
    length       220 mm (from HCAL to Endcap support plate)
    
    inner radius  32 cm (eta=3)
**  outer radius  39 cm (eta ~ 2.8)

 a vertical moderator
    thickness      8 cm , sitting behind the endcap support plate
    inner radius  50 cm
    outer radius 100 cm           

 then thinning down to
    thickness      4 cm
    inner radius 100 cm
    outer radius 130 cm

Appendix 2 Preshower details 
******************************

   CMS ENDCAP ECAL PRESHOWER : WEIGHT INVENTORY  ,  very approximative
   
   per endcap  ( surface app. 467 dm^2 )
   

moderators (2)        : 0.8 dm * 467 dm^2 *1 kg/dm^3  =  374 kg
Al for absorbers (2)  : 0.12     467       2.7           151 kg
Pb for absorbers (2)  : 0.166    467       11.3          876 kg
tiles-micromodules(2) : 0.08     467       2.7           101 kg
electronics planes(2) :                                  100 kg
overhead ( vessel,cables,feedthroughs,support,water,..)  250 kg
							--------
							1852 kg
  
 ***       Note 1 dm = 0.1 metres = 10 cm ****
 *** The endcap preshower is app. 4.67 m^2 ***

Wertelaers , 11.07.97