C++ Interface to Tauola
FA1RCHL.f
1 COMPLEX FUNCTION fa1rchl(QQ)
2 IMPLICIT NONE
3 REAL QQ
4 DOUBLE PRECISION M1,M2,M3
5 REAL GGMA1
6 REAL wid_a1_fit
7c.......................................................................
8c.
9c. fa1chl - rcht version of the a1 propagator
10c.
11c. inputs : qq - invariant masses**2 [gev**2]
12c. outputs : fa1rchl formfactor value at qq
13c.
14c. COMMON : rcht_3pi content is defined in this routine
15c.
16c. calls : functions from file ./wid_a1_fit.f
17c. called : from file f3pi_rcht.f, fkkpi.f, fkk0pi0.f
18c************************************************************************
19 include '../parameter.inc'
20 include '../funct_declar.inc'
21c******************************************
22c initilisation of the mass of the particles
23c*****************************************
24 call rchl_parameters(5)
25
26c$$$c we impose isospin symmetry requesting that charged and neutral pion mass
27c$$$c are equal. this may need to be changed
28c$$$ mmpi_av = (2.*mpic+mpiz)/3.
29
30 m1 = mmpi_av
31 m2 = mmpi_av
32 m3 = mmpi_av
33c
34c Function wid_a1_fit.f calculates the energy dependence of
35c the a1 meson width
36c
37 IF(qq.GE.(m1+m2+m3)**2) THEN
38 ggma1 = wid_a1_fit(qq)
39 ELSE
40 ggma1 = 0.
41 ENDIF
42
43
44 fa1rchl = 1./(qq-mma1*mma1+i*mma1*ggma1)
45
46 RETURN
47 END
48
49c to switch on/off remotely option for scalar contr.
50c to form1 form2 of 3 pi mode.
51 subroutine getff3piscal(INUM)
52 INTEGER INUM
53 include '../parameter.inc'
54 inum=ff3piscal
55 return
56 end
57
58 subroutine setff3piscal(INUM)
59 INTEGER INUM
60 include '../parameter.inc'
61 ff3piscal=inum
62 return
63 end