$IAEA_INDEX: 110 // IAEA website: www-nds.iaea.org/phsp/photon/ $TITLE: Siemens PRIMUS 6MV photon beam 5.0 x 5.0 cm2 field $FILE_TYPE: 0 $CHECKSUM: 256344311 $RECORD_CONTENTS: 1 // X is stored ? 1 // Y is stored ? 0 // Z is stored ? 1 // U is stored ? 1 // V is stored ? 1 // W is stored ? 1 // Weight is stored ? 0 // Extra floats stored ? 1 // Extra longs stored ? 2 // LATCH EGS variable stored in the extralong array [ 0] $RECORD_CONSTANT: 95.0000 // Constant Z $RECORD_LENGTH: 29 $BYTE_ORDER: 1234 $ORIG_HISTORIES: 15000000 $PARTICLES: 8839459 $PHOTONS: 8822871 $ELECTRONS: 16340 $POSITRONS: 248 $TRANSPORT_PARAMETERS: Photon transport cutoff(MeV)->0.010 Pair angular sampling->KM Pair cross sections->BH Triplet production->Off Bound Compton scattering->ON Radiative Compton corrections->Off Rayleigh scattering->ON Atomic relaxations->ON Photoelectron angular sampling->ON Electron transport cutoff(MeV)->0.001 Bremsstrahlung cross sections->NIST Bremsstrahlung angular sampling->KM Spin effects->On Electron Impact Ionization->Off Maxium electron step in cm (SMAX)->5.000 Maximum fractional energy loss/step (ESTEPE)->0.2500 Maximum 1st elastic moment/step (XIMAX)->0.5000 Boundary crossing algorithm->EXACT Skin-depth for boundary crossing (MFP)->3.000 Electron-step algorithm->PRESTA-II $MACHINE_TYPE: SIEMENS PRIMUS 6MV $MONTE_CARLO_CODE_VERSION: version V1 of BEAMnrc (Rev 1.78 last edited 2004-01-12 11:44:06-05) $GLOBAL_PHOTON_ENERGY_CUTOFF: 0.010 $GLOBAL_PARTICLE_ENERGY_CUTOFF: 0.001 $COORDINATE_SYSTEM_DESCRIPTION: Cartesian Right-Handed, origin: z=0->bottom of the target, x=y=0->central position of the target, z-axis parallel to beam direction, incresing towards the patient, x-axis parallel to MLC leaf movement // OPTIONAL INFORMATION $BEAM_NAME: 6MV photon beam $FIELD_SIZE: 5.0 cm x 5.0 cm $NOMINAL_SSD: 100 cm $MC_INPUT_FILENAME: $VARIANCE_REDUCTION_TECHNIQUES: Bremsstrahlung splitting->DIRECTIONAL splitting field radius->4.000 cm splitting field SSD->100.000 cm splitting no. in field->1500 Photon force interaction switch->OFF Range rejection switch->ON $INITIAL_SOURCE_DESCRIPTION: INITIAL PARTICLES->Electrons PARALLEL BEAM WITH 2-D GAUSSIAN X-Y DISTRIBUTION ON FRONT FACE at Z->0.0000 cm BEAM FWHM->0.10 cm INCIDENT ENERGY SPECTRUM READ FROM .specdata FILE ============================================================================================ Energy spectrum: gaussian centred at 6 MeV, FWHM =0.84 MeV 30, 4.90, 1 4.98, 1.4181119E-02 5.05, 2.5347747E-02 5.12, 4.3465299E-02 5.20, 7.1502697E-02 5.27, 1.1284451E-01 5.34, 1.7085137E-01 5.41, 2.4816358E-01 5.49, 3.4581247E-01 5.56, 4.6230390E-01 5.63, 5.9292519E-01 5.71, 7.2955606E-01 5.78, 8.6120131E-01 5.85, 9.7530087E-01 5.93, 1.0596464E+00 6.00, 1.1045161E+00 6.07, 1.1045161E+00 6.15, 1.0596464E+00 6.22, 9.7530087E-01 6.29, 8.6120131E-01 6.37, 7.2955606E-01 6.44, 5.9292519E-01 6.51, 4.6230390E-01 6.59, 3.4581247E-01 6.66, 2.4816358E-01 6.73, 1.7085137E-01 6.80, 1.1284451E-01 6.88, 7.1502697E-02 6.95, 4.3465299E-02 7.02, 2.5347747E-02 7.10, 1.4181119E-02 ============================================================================================ MEAN ENERGY->6.0 MeV MINIMUM KINETIC ENERGY OF SPECTRUM->4.900 MeV MAXIMUM KINETIC ENERGY OF SPECTRUM->7.100 MeV NUMBER OF BINS IN SPECTRUM->30 $PUBLISHED_REFERENCE: 1->Automatic determination of primary electron beam parameters in Monte Carlo simulation. 2007, Med. Phys. 34, 1076-1084 2->A new method for output factor determination in MLC shaped narrow beams. Physica MEDICA 23 (2007) 58-66 3->Monte Carlo correction factors in small field absolute dosimetry: a feasibility study (Unpublished, available from the phsp web site) $AUTHORS: J PENA, D M GONZALEZ-CASTANO, F SANCHEZ-DOBLADO, G HARTMANN $INSTITUTION: UNIVERSIDAD DE SANTIAGO DE COMPOSTELA (SPAIN) $LINK_VALIDATION: $ADDITIONAL_NOTES: This is IAEA header as defined in the technical report IAEA(NDS)-0484, Vienna, 2006 $STATISTICAL_INFORMATION_PARTICLES: // Weight Wmin Wmax Emin Emax Particle 6387.5 4.444E-07 1 1.816 0.007104 7.043 PHOTONS 17.8887 0.0006667 1 1.949 0.01019 6.264 ELECTRONS 0.165333 0.0006667 0.0006667 1.666 0.1264 5.429 POSITRONS $STATISTICAL_INFORMATION_GEOMETRY: -14.9876 14.9695 -14.98 14.9855