CDC structure Shoji Uno (KEK) July-8, 2009
Baseline Design sBelle Belle MAPS = Monolithic Active Pixel Sensor 2
Tentative drawing by Kohriki-san
Connection regions 1 Endplate and Outer cylinder Main and Conical (Backward)
Connection regions 2 Main and Conical (Forward) Backward Forward
Connection regions 3 Conical and Small cell Small cell and Inner cylinder
Main parameters Present Future 77 160 880 1096 88 168 863 1082 50 58 Radius of inner boundary (mm) 77 160 Radius of outer boundary (mm) 880 1096 Radius of inner most sense wire (mm) 88 168 Radius of outer most sense wire (mm) 863 1082 Number of layers 50 58 Number of total sense wires 8400 15104 Effective radius of dE/dx measurement (mm) 752 928 Gas He-C2H6 Diameter of sense wire (mm) 30
Calculation of deformation and etc Deformation of Aluminum endplate Thickness of endplate 10mm Tension of field wire 120g 80g Gravitational sag, Sense : 190mm(50g), Field:300mm(80g) Unequal sag Nane-san’s talk Total tension ~4ton Deformation Yamaoka-san’s talk Stress calculation Thickness of outer cylinder CFRP:mm Transition structure between endplate and outer cylinder Bucking calculation for inner cylinder Larger tension for many wires ( ~400kg) Yamaoka-san’s talk
Weight Endplate Outer Cylinder Electronics Board Al, Thickness : 10mm 110kgx2 = 220kg Outer Cylinder CRRP, Thickness : 5mm 210kg Electronics Board G10, 48ch/board 0.3kgx315 = 95kg
Wire configuration So far, But, 48ch/board 16X3 8(A),6(U),6(A),6(V),6(A),6(U),6(A),6(V),8(A), 58 layers in total But, Readout board 64ch/board 16x4 No good assignment 48ch/board 16X3 8(A) 2(A)+6(A) inner most super layer 2(A) special treatment 160x2=320 : 48x7=336 8(A) 6(A) outer most super layer 56 layers in total Good assignment Other good idea is highly welcome.
Readout board space Test board 16ch 48ch(~300boards in total) 17.5cm Should be fit in volume 20cm
My Personal Plan for Construction