4 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
5 * See cxx source for full Copyright notice */
10 // z-positions defining the absorber
11 // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
12 // start of the absorber
13 const Float_t abs_d = 90.;
15 const Float_t z_nose = 102.;
16 // end of the 5deg line below the TPC field cage
17 const Float_t z_cone = 285.;
19 const Float_t abs_cc = 315.;
20 // start of inner opening cone
21 const Float_t abs_c = 362.;
22 // const Float_t abs_c = 300.;
23 // rear end of the absorber
24 const Float_t abs_l = 503.;
25 // thickness of rear shield
26 const Float_t d_rear = 35.;
28 // angles defining the absorber
29 // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
31 const Float_t theta1 = 24.*kDegrad;
32 // angle of second outer cone below field cage
33 const Float_t theta2 = 5. *kDegrad;
34 // outer angler of W rear shield
35 const Float_t theta_r = 3. *kDegrad;
36 // max acceptance angle
37 const Float_t acc_max = 10.*kDegrad;
38 // min acceptance angle
39 const Float_t acc_min = 2. *kDegrad;
40 // opening angle of inner shielding cone
41 const Float_t theta_open = 0.7*kDegrad;
42 const Float_t theta_open1 = 1.1*kDegrad;
43 // const Float_t theta_open1 = 0.70*kDegrad;
44 const Float_t theta_open2 = 0.8*kDegrad;
45 const Float_t theta_open3 = 0.9*kDegrad;
47 // thicknesses defining the absorber
48 // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
50 const Float_t d_steel = 1.;
51 // poly-ethylene layer
52 const Float_t d_poly = 5.0;
54 // radii defining the absorber
55 // ^^^^^^^^^^^^^^^^^^^^^^^^^^^
56 // absorber inner radius
57 const Float_t r_abs = 4.95;
59 const Float_t epsilon = .01;
61 // start of 2 deg cone defined by absorber inner radius
62 Float_t z_2deg = r_abs/tan(acc_min);
65 // Index of heavy shield material
68 // y-position of trigger wall
69 const Float_t zfil_in = 1471.;
70 const Float_t zfil_out = zfil_in+120.;
71 // end of 2-degree outer cone
72 const Float_t zcone_e = 30./TMath::Tan(acc_min);
73 // end of opening cone
74 const Float_t zcone_c = 1800.;
75 const Float_t z_out = 1900.;
78 const Float_t cz1= 511;
79 const Float_t cz2= 686;
81 // Radii and z-positions imposed by vacuum chamber layout
84 // delta_R for bellows
85 const Float_t dr11=1.8;
87 const Float_t dr12=0.875;
88 // delta_R to catch up with cone
89 const Float_t dr13=0.525;
91 const Float_t dF1=2.*3.9;
93 const Float_t dB1=18.482-dF1/2-dr11;
95 const Float_t zvac2=518.;
96 const Float_t zvac1=zvac2-dF1/2-dB1-dr11-dr12;
97 const Float_t zvac3=zvac2+dF1/2+dB1+dr11+dr13;
98 const Float_t zvac4=558.;
99 // Outer shield dimensions
100 const Float_t R11=15.45;
102 const Float_t dRSteel1=2.;
103 const Float_t dRSteel2=4.;
104 // According to design
105 // const Float_t R21=20.3;
106 // to avoid overlap with 2deg line
107 const Float_t R21=19.4;
112 const Float_t zvac5=zvac4+4.;
117 const Float_t zvac6=711.;
118 const Float_t zvac8=1274.;
119 const Float_t dr21=2.263;
120 const Float_t dr22=1.3;
121 const Float_t dr23=0.1;
122 const Float_t dB2=24.118;
123 const Float_t dF2=10.6;
124 const Float_t zvac7=zvac8-dF2/2-dB2-dr22-dr21;
125 const Float_t zvac9=zvac8+dF2/2+dB2+dr22+dr23;
130 const Float_t zvac10=1466.;
131 const Float_t zvac11=1800.;
132 const Float_t zvac12=1900.;
134 const Float_t R41=35.;
135 const Float_t R42=50.;
136 const Float_t R43=110.;
141 // beam pipe outer radius
142 // absorber inner radius
144 const Float_t d_tube=0.1;
145 const Float_t d_insu=0.9;
146 const Float_t d_enve=0.1;
147 const Float_t d_prot=0.2;
148 const Float_t d_free=0.5;
150 const Float_t d_vacu=d_tube+d_insu+d_enve+d_prot+d_free;
151 const Float_t r_vacu=r_abs-d_vacu;
157 const Float_t rB1=5.5;
158 const Float_t hB1=2.25;
159 const Float_t lB1=0.77;
160 const Float_t eB1=0.04;
164 const Float_t rF1=8.5;
165 const Float_t d_flange=0.1;
170 const Float_t rB2=15.35;
171 const Float_t hB2=2.25;
172 const Float_t lB2=2.32;
173 const Float_t eB2=0.05;
177 const Float_t rF2=18.8;
182 const Float_t dzch=10.;
183 const Float_t zch1=532.5;
184 const Float_t zch2=690.;