source: sasview/sansmodels/src/sans/models/c_extensions/core_shell_cylinder.h @ 836fe6e

#if !defined(core_shell_cylinder_h)
#define core_shell_cylinder_h

/**
 * Structure definition for core-shell cylinder parameters
 */
 //[PYTHONCLASS] = CoreShellCylinderModel
 //[DISP_PARAMS] = radius, thickness, length, axis_theta, axis_phi
 //[DESCRIPTION] = <text>P(q,alpha)= scale/Vs*f(q)^(2) + bkg  Where:\n\
 //                                              f(q)= 2(core_sld- solvant_sld)* Vc*sin[qLcos(alpha/2)]/\n\
 //                                             [qLcos(alpha/2)]*J1(qRsin(alpha))/[qRsin(alpha)] +\n 2(shell_sld-solvent_sld)*Vs
 //                                             *sin[q(L+T)cos(alpha/2)]/[[q(L+T)cos(alpha/2)]
 //                                             *J1(q(R+T)sin(alpha))/q(R+T)sin(alpha)]
 //                                             alpha:is the angle between the axis of the cylinder and the q-vector
 //                                             Vs: the volume of the outer shell
 //                                             Vc: the volume of the core
 //                                             L: the length of the core
 //                                     shell_sld: the scattering length density of the shell
 //                                             solvent_sld: the scattering length density of the solvent
 //                                             bkg: the background
 //                                             T: the thickness
 //                                     R+T: is the outer radius
 //                                     L+2T: The total length of the outershell
 //                                             J1: the first order Bessel function
 //                                     theta: axis_theta of the cylinder
 //                                     phi: the axis_phi of the cylinder
 //                                     </text>
 //[FIXED]= <text> axis_phi.width; axis_theta.width; length.width;radius.width; thickness_width</text>

typedef struct {
    /// Scale factor
    //  [DEFAULT]=scale=1.0
    double scale;

    /// Core radius [A]
    //  [DEFAULT]=radius=20.0 A
    double radius;

    /// Shell thickness [A]
    //  [DEFAULT]=thickness=10.0 A
    double thickness;

    /// Core length [A]
    //  [DEFAULT]=length=400.0 A
    double length;

    /// Core SLD [A-2]
    //  [DEFAULT]=core_sld=1.0e-6 A-2
    double core_sld;

    /// Shell SLD [A-2]
    //  [DEFAULT]=shell_sld=4.0e-6 A-2
    double shell_sld;

    /// Solvent SLD [A-2]
    //  [DEFAULT]=solvent_sld=1.0e-6 A-2
    double solvent_sld;

        /// Incoherent Background [cm-1]
        //  [DEFAULT]=background=0 cm-1
        double background;

    /// Orientation of the long axis of the core-shell cylinder w/respect incoming beam [rad]
    //  [DEFAULT]=axis_theta=1.57 rad
    double axis_theta;

    /// Orientation of the long axis of the core-shell cylinder in the plane of the detector [rad]
    //  [DEFAULT]=axis_phi=0.0 rad
    double axis_phi;

} CoreShellCylinderParameters;



/// 1D scattering function
double core_shell_cylinder_analytical_1D(CoreShellCylinderParameters *pars, double q);

/// 2D scattering function
double core_shell_cylinder_analytical_2D(CoreShellCylinderParameters *pars, double q, double phi);
double core_shell_cylinder_analytical_2DXY(CoreShellCylinderParameters *pars, double qx, double qy);
double core_shell_cylinder_analytical_2D_scaled(CoreShellCylinderParameters *pars, double q, double q_x, double q_y);

#endif