//////////////////////////////////////////////////////////////////////////////
//                 input file for injection envelope tracking               //
//////////////////////////////////////////////////////////////////////////////

OPTION, VERSION = 20000;
OPTION, PSDUMPFREQ = 300;   // 6d data written every 300 time steps (h5).
OPTION, STATDUMPFREQ = 10;  // Beam Stats written every 10 time steps (stat).
//OPTION, BOUNDPDESTROYFQ=10; // Delete lost particles, if any
OPTION, AUTOPHASE=4;        // Autophase is on, and phase of max energy
                            // gain will be found automatically for cavities.

Title, string="Injector";

//----------------------------------------------------------------------------
//Global Parameters

REAL h              = 2;          //harmonic number
REAL f0             = 37.4179197618764e6;         //Hz
REAL f1             = h*f0;
REAL sigmarf        = 1;         //rf sigma for injected bunch (degree)

REAL n_particles    = 1e4;       //Number of particles in simulation
REAL nsteps         = 100000;    //Number of steps
REAL current        = 10e-3;      //Current (mA)

//Initial Momentum Calculation
REAL Eo      = 0.04;              //initial energy in MeV
REAL Edes    = Eo/1000;             
REAL gamma   = (Edes+PMASS)/PMASS; 
REAL beta    = sqrt(1-(1/gamma^2));
REAL gambet  = gamma*beta;
REAL P0      = gamma*beta*PMASS; //inital z momentum
REAL sigmaZ  = sigmarf/360/f0*beta*CLIGHT;

//Printing initial energy and momentum to terminal output.
value , {Edes, P0, sigmaZ};

//----------------------------------------------------------------------------
// RF photoinjector (Gun)
//
// Cavity/RF field.
//
// L:        physical element length (real in m). Length (of field map) (m).
// VOLT:     field scaling factor (real). RF field magnitude (MV/m).
// FMAPFN:   file name, or full path name to file (string)
// ELEMEDGE: physical start of the element on the floor (m)
// TYPE:     specifies "STANDING", "TRAVELLING" or "SINGLE GAP" structure
// FREQ:     RF frequency of cavity (real in MHz). Resonance frequency.
// LAG:      cavity phase (radians)
//

//gun_inj_phase = 0.0;  // Rf injection phase (in degrees) with restpect 
                      // to max phase. i.e. 0.0 inj phase corresponds 
                      // to running on crest (max energy).

//GUN:    RFCavity, L = 0.2927, VOLT = 60.0, ELEMEDGE = 0.0, TYPE = "STANDING",
//        FMAPFN = "DriveGun.T7", FREQ = 1300.0, LAG = (gun_inj_phase*Pi)/180.0; 
        //LAG (phase) is converted to radians

//----------------------------------------------------------------------------
//Drift after gun.

DR1: DRIFT, L = 1, ELEMEDGE = 0;

//----------------------------------------------------------------------------
// DEFINE BEAM LINE

//GS:  Line = (GUN, BF, M);

// Complete accelerator
DRIVE: Line = ( DR1);

//----------------------------------------------------------------------------
// INITIAL DISTRIBUTION
//
// Flattop distribution. 
// SIGMAX/Y:      RMS radius of transverse beam size (Laser radius in m). 
// TRISE/FALL:    Rise time/fall time in longitudinal direction (s).
// TPULSEFWHM:    FWHM in longitudinal direction (s).
// CUTOFFLONG:    Longitudinal cuttoff in units of sigma.
// NBIN:          Number of energy bins to use during emission.
// DEBIN:         Defines when to combine bins (Min energy difference in KeV). 
// EMISSIONSTEPS: Number of steps during emssion. 
//                Emission time step is adjusted to fit this number.
// EKIN:          Kinetic energy of electrons at emission (eV). 
// ELASER:        Energy of laser (eV). 
// W:             Photocathode work functioin (eV). 
// FE:            Fermi energy of photocathode (eV). 
// CATHTEMP:      Operating temperature of photocathode (K). 

// Note, ELASER, W, FE, and CATHTEMP are used for the NONEQUIL emission model.
// These values are not necessary when using other models.

Dist:DISTRIBUTION, TYPE=gauss, INPUTMOUNITS=NONE, sigmax= 1e-03, sigmapx=gambet*10e-3, corrx=0.0, sigmay=1e-3, sigmapy=gambet*10e-3, corry=0.0, sigmaz= sigmaZ, sigmapz=gambet*5e-3, corrz=0.0;

// Note on emission time step: FWHM pulse width divided by emission 
// steps gives the time step for the emissions process. 
// i.e 20.0e-12 / 100 gives a time step of 2e-13 (s) during emission. 
// This is the not the same as the time step used in rest of the file. 

//----------------------------------------------------------------------------
// Define Field solvers
// The mesh sizes should be a factor of 2 
// for most efficient space charge calculation.

FS_SC: Fieldsolver, FSTYPE = FFT, 
            MX = 16, MY = 16, MT = 16, // SC grid size is 16^3
            PARFFTX = true, 
            PARFFTY = true, 
            PARFFTT = false,  
            BCFFTX = open, 
            BCFFTY = open, 
            BCFFTT = open,
            BBOXINCR = 1, 
            GREENSF = INTEGRATED;

BEAM1:  BEAM, PARTICLE = PROTON, pc = P0, NPART = n_particles,
        BFREQ = f1,BCURRENT = current, CHARGE = 1;

TRACK, LINE = DRIVE, BEAM = BEAM1, MAXSTEPS = nsteps, DT = {1.0e-11}, ZSTOP={1.0};

RUN, METHOD = "PARALLEL-T", BEAM = BEAM1, FIELDSOLVER = FS_SC, DISTRIBUTION = Dist;
ENDTRACK;

Stop;
Quit;