1 jones 1.1       real*8 function vmag(u)
 2           
 3                 implicit none
 4           
 5                 real*8 u(3)
 6           
 7                 vmag = sqrt(u(1)**2 + u(2)**2 + u(3)**2)
 8           
 9                 return
10                 end
11           
12           C------------------------------------------------------------------------------
13           
14                 real*8 function scat_angle(u)
15           
16                 include 'constants.inc'
17                 include 'sane.inc'
18           
19                 real*8 u(3)
20                 real*8 vmag
21                 real*8 tht0
22 jones 1.1 
23           
24           * Rotate from calorimeter coordinates to beam coordinates
25           
26                 tht0 = theta_0*d2r
27           
28                 scat_angle = acos( (-sin(tht0)*u(2) + cos(tht0)*u(3))/vmag(u) )/d2r
29           
30                     ! in degrees
31           
32                 return
33                 end
34           
35           C------------------------------------------------------------------------------
36           
37                 real*8 function momentum(u,part)
38           
39                 include 'constants.inc'
40           
41                 real*8 u(3)
42                 integer*2 part
43 jones 1.1 
44                 real*8 beta,gamma
45                 real*8 vmag
46           
47                 beta = vmag(u)/cc
48                 gamma = 1.d0/sqrt(1.d0-beta**2)
49                 momentum = gamma*mass(part)*beta
50           
51                 return
52                 end
53