ZGOUBI USERS' GUIDE - HEP

4.5 Output Procedures 129wSPNPRNL, SPNPRNLA, SPNPRT: Print/Store spin coordinatesSPNPRNL has the same effect as SPNPRT (see below), except that the information is stored in a dedicated file FNAME(standard is FNAME = ‘zgoubi.spn’ for post-processing with zpop). The data are formatted and ordered according to theFORTRAN sequence belowOPEN (UNIT = NL, FILE = FNAME, STATUS = ‘NEW’)DO 1 I=1, IMAXWRITE (NL,100) LET(I), IEX(I), (SI(J,I)J=1,4), (SF(J,I),J=1,4), GAMMA, I100 FORMAT(1X, A1, I2, 1P, 8E15.7, /, E15.7, 2I3, I6)1 CONTINUE· § · · The meaning of these parameters is the followingLET(I),IEX(I) : tagging character and flag (see OBJET)SI(1-4,I) : spin components , , and modulus, at the originSF(1-4,I) : idem, at the current positionGAMMA : Lorentz relativistic factorI: particle numberIMAX : total number of particles ray-traced (see OBJET)IPASS : turn number (see REBELOTE)SPNPRNLA has an effect similar to SPNPRNL, with one more feature. The line next to FNAME gives a ¤¥ parameter. qprinting will occur every ¤¦¥ other pass, when using REBELOTE with NPASS Ž8¤¦¥SPNPRT can be introduced anywhere in a structure. It produces a listing (into zgoubi.res) of the initial and actualcoordinates and modulus of the spin of the IMAX particles, at the location where it stands, together with their Lorentzfactor Á , following the format detailed above. The mean values of the spin components are also printed.