controls muon photonuclear interactions See also PAIRBREM, PHOTONUCWHAT(1): flag to switch on photonuclear interactions: = -1.0 : no muon photonuclear interaction = 0.0 : ignored = 1.0 : photonuclear interactions on and secondary hadrons produced = 2.0 : photonuclear interactions on but no secondary hadrons producedDefault= 1.0 if no DEFAULTS card is present, or if it is present withSDUM= CALORIMEtry, NEW-DEFAults, ICARUS or PRECISIOn. = -1.0 otherwise * Start_Devel_seqWHAT(2)= ratio of longitudinal to transverse photon cross section Warning: for code development only, do not change! If changed the new value is applied to ALL materials.Default= 0.25.WHAT(3)= fraction of rho-like/VMD interactions ( must be < 1). Warning: for code development only, do not change! If changed the new value is applied to ALL materials.Default= 0.75. * End_Devel_seq * Start_Prod_seqWHAT(2)-WHAT(3): reserved for code development * End_Prod_seqWHAT(4)= lower bound of the indices of the materials, or corresponding name, in which muon nuclear interactions must be simulated ("From materialWHAT(4)...").Default= 3.0.WHAT(5)= upper bound of the indices of the materials, or corresponding name, in which muon nuclear interactions must be simulated ("...to materialWHAT(5)...")Default=WHAT(4)WHAT(6)= step length in assigning indices. ("...in steps ofWHAT(6)").Default= 1.0Notes:1) Other high-energy interactions of muons with nuclei (pair production, bremsstrahlung) are controlled by option PAIRBREM, which applies also to charged hadrons. 2) Use ofWHAT(1)= 2.0 (interaction without transport of the secondaries) gives the correct muon straggling but simulates only in an approximate way the energy deposition distribution. A similar approach is found in A. Van Ginneken's codes CASIM and MUSIM [Van75,Van86]. Example (number based):* Explicit pair production and bremsstrahlung requested for heavy charged* particles in materials 12 and 13, provided the energy of the secondary* electrons and positrons is > 500 keV. No threshold is requested for photon* production. For muons, explicit nuclear interactions are also requested.*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...PAIRBREM 3.0 0.0 0.0005 12.0 13.0 MUPHOTON 1.0 0.0 0.0 12.0 13.0 The same example, name based:*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...PAIRBREM 3.0 0.0 0.0005 COPPER SILVER MUPHOTON 1.0 0.0 0.0 COPPER SILVER * Start_Devel_seq