Optical potentials¶

This page collects the built-in optical-potential interfaces, parameterizations, and helper utilities.

Optical-potential models and helper potential forms.

class jitr.optical_potentials.LocalOpticalPotential(scale_radii_by_At_and_Ap=False)[source]¶

Bases: SingleChannelOpticalModel

Simple local optical potential with optional nucleus-nucleus radius scaling.

Parameters:: scale_radii_by_At_and_Ap (bool)

radius_factor(reaction_model)[source]¶

Return the radius scaling factor for the current reaction.

Return type:: float
Parameters:: reaction_model (Reaction)

evaluate(rgrid, reaction_model, kinematics_model, Vv, rv, av, Wv, rw, aw, Wd, Vd, rd, ad, Vso, Wso, rso, aso, rC)[source]¶

Evaluate the local optical-potential terms on rgrid.

Return type:

tuple[complex | ndarray[tuple[Any, ...], dtype[cdouble]], complex | ndarray[tuple[Any, ...], dtype[cdouble]], complex | ndarray[tuple[Any, ...], dtype[cdouble]] | float | ndarray[tuple[Any, ...], dtype[double]]]

Parameters:

rgrid (float | ndarray[tuple[Any, ...], dtype[float64]])
reaction_model (Reaction)
kinematics_model (ChannelKinematics)
Vv (float)
rv (float)
av (float)
Wv (float)
rw (float)
aw (float)
Wd (float)
Vd (float)
rd (float)
ad (float)
Vso (float)
Wso (float)
rso (float)
aso (float)
rC (float)

class jitr.optical_potentials.SingleChannelOpticalModel(params)[source]¶

Bases: object

Base class for local single-channel optical potentials.

Parameters:: params (list[str])

evaluate(rgrid, reaction, kinematics, *params)[source]¶

Evaluate central, spin-orbit, and Coulomb terms on rgrid.

Return type:

Parameters:

rgrid (float | ndarray[tuple[Any, ...], dtype[float64]])
reaction (Reaction)
kinematics (ChannelKinematics)
params (float)

jitr.optical_potentials.coulomb_charged_sphere(r, zz, r_c)[source]¶

Return the Coulomb potential of a uniformly charged sphere.

Return type:

float | ndarray[tuple[Any, ...], dtype[double]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
zz (float)
r_c (float)

jitr.optical_potentials.perey_buck_nonlocal(r, rp, *params)[source]¶

Return the Perey-Buck nonlocal kernel factor.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float)
rp (float)
params (float)

jitr.optical_potentials.regular_inverse_r(r, r_c)[source]¶

Return 1/r regularized inside a sphere of radius r_c.

Return type:

float | ndarray[tuple[Any, ...], dtype[double]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
r_c (float)

jitr.optical_potentials.surface_peaked_gaussian_potential(r, *params)[source]¶

Return a simple surface-peaked Gaussian potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
params (float)

jitr.optical_potentials.thomas_mean_square_radius(R, a)[source]¶

Return the mean-square radius for the Thomas spin-orbit shape.

Return type:

float

Parameters:

R (float)
a (float)

jitr.optical_potentials.thomas_safe(r, R, a)[source]¶

Evaluate the Thomas spin-orbit shape without overflow issues.

Return type:

float | ndarray[tuple[Any, ...], dtype[double]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
R (float)
a (float)

jitr.optical_potentials.thomas_volume_integral(V, R, a)[source]¶

Return the volume integral for the Thomas spin-orbit shape.

Return type:

float

Parameters:

V (float)
R (float)
a (float)

jitr.optical_potentials.woods_saxon_mean_square_radius(R, a)[source]¶

Return the mean-square radius for a Woods-Saxon term.

Return type:

float

Parameters:

R (float)
a (float)

jitr.optical_potentials.woods_saxon_potential(r, *params)[source]¶

Return a Woods-Saxon potential with complex depth V + iW.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
params (float)

jitr.optical_potentials.woods_saxon_prime(r, *params)[source]¶

Return the radial derivative of a Woods-Saxon potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
params (float)

jitr.optical_potentials.woods_saxon_prime_mean_square_radius(R, a)[source]¶

Return the mean-square radius for a derivative Woods-Saxon term.

Return type:

float

Parameters:

R (float)
a (float)

jitr.optical_potentials.woods_saxon_prime_safe(r, R, a)[source]¶

Evaluate the radial derivative of the Woods-Saxon shape safely.

Return type:

float | ndarray[tuple[Any, ...], dtype[double]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
R (float)
a (float)

jitr.optical_potentials.woods_saxon_prime_volume_integral(V, R, a)[source]¶

Return the volume integral for a derivative Woods-Saxon term.

Return type:

float

Parameters:

V (float)
R (float)
a (float)

jitr.optical_potentials.woods_saxon_safe(r, R, a)[source]¶

Evaluate a Woods-Saxon shape while avoiding overflow in exp.

Return type:

float | ndarray[tuple[Any, ...], dtype[double]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
R (float)
a (float)

jitr.optical_potentials.woods_saxon_volume_integral(V, R, a)[source]¶

Return the volume integral for a Woods-Saxon term.

Return type:

float

Parameters:

V (float)
R (float)
a (float)

jitr.optical_potentials.yamaguchi_potential(r, rp, *params)[source]¶

Return the Yamaguchi separable nonlocal potential.

Return type:

float

Parameters:

r (float)
rp (float)
params (float)

jitr.optical_potentials.yamaguchi_swave_delta(k, *params)[source]¶

Return the analytic s-wave phase shift for the Yamaguchi potential.

Return type:

double

Parameters:

k (float)
params (float)

Base classes and helpers for single-channel optical potentials.

class jitr.optical_potentials.omp.SingleChannelOpticalModel(params)[source]¶

Bases: object

Base class for local single-channel optical potentials.

Parameters:: params (list[str])

evaluate(rgrid, reaction, kinematics, *params)[source]¶

Evaluate central, spin-orbit, and Coulomb terms on rgrid.

Return type:

Parameters:

rgrid (float | ndarray[tuple[Any, ...], dtype[float64]])
reaction (Reaction)
kinematics (ChannelKinematics)
params (float)

jitr.optical_potentials.omp.central(r, Vv, Rv, av, Wv, Rw, aw, Wd, Vd, Rd, ad)[source]¶

Evaluate the default Woods-Saxon central potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
Vv (float)
Rv (float)
av (float)
Wv (float)
Rw (float)
aw (float)
Wd (float)
Vd (float)
Rd (float)
ad (float)

jitr.optical_potentials.omp.spin_orbit(r, Vso, Wso, Rso, aso)[source]¶

Evaluate the default Thomas-form spin-orbit potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

Parameters:

r (float | ndarray[tuple[Any, ...], dtype[float64]])
Vso (float)
Wso (float)
Rso (float)
aso (float)

class jitr.optical_potentials.omp.LocalOpticalPotential(scale_radii_by_At_and_Ap=False)[source]¶

Bases: SingleChannelOpticalModel

Simple local optical potential with optional nucleus-nucleus radius scaling.

Parameters:: scale_radii_by_At_and_Ap (bool)

radius_factor(reaction_model)[source]¶

Return the radius scaling factor for the current reaction.

Return type:: float
Parameters:: reaction_model (Reaction)

evaluate(rgrid, reaction_model, kinematics_model, Vv, rv, av, Wv, rw, aw, Wd, Vd, rd, ad, Vso, Wso, rso, aso, rC)[source]¶

Evaluate the local optical-potential terms on rgrid.

Return type:

Parameters:

rgrid (float | ndarray[tuple[Any, ...], dtype[float64]])
reaction_model (Reaction)
kinematics_model (ChannelKinematics)
Vv (float)
rv (float)
av (float)
Wv (float)
rw (float)
aw (float)
Wd (float)
Vd (float)
rd (float)
ad (float)
Vso (float)
Wso (float)
rso (float)
aso (float)
rC (float)

The Koning-Delaroche potential is a common optical potential for nuclear scattering. It is provided here in simplified form specifically to address this need.

See the [Koning-Delaroche paper](https://www.sciencedirect.com/science/article/pii/S0375947402013210) for details. Equation references are with respect to (w.r.t.) this paper.

jitr.optical_potentials.kduq.get_param_names(projectile)[source]¶

Get the names of the parameters for the given projectile, in the order they are returned by get_kd03() and get_samples().

Return type:: list[str]
Parameters:: projectile (tuple[int, int])

jitr.optical_potentials.kduq.get_kd03(projectile)[source]¶

Return the original KD03 frequentist parameter vector for the given projectile.

This is the single parameter set loaded by Global when no explicit param_fpath is supplied. The returned vector follows the ordering from get_param_names() so it can be passed directly into calculate_params() or compared with rows returned by get_samples().

Parameters:: projectile (tuple[int, int]) – tuple (Ap, Zp) of the projectile. Must be (1, 0) for neutron or (1, 1) for proton.
Return type:: ndarray
Returns:: A one-dimensional array containing the KD03 frequentist parameter set.

jitr.optical_potentials.kduq.get_samples(projectile, posterior='federal')[source]¶

Get the posterior samples for the given projectile (neutron or proton) from the KDUQ Federal or Democratic posteriors.

These samples are distinct from the original KD03 frequentist parameter set returned by get_kd03().

See [Pruitt, et al., 2023] (https://journals.aps.org/prc/pdf/10.1103/PhysRevC.107.014602) for details on the KDUQ posteriors.

Parameters:

projectile (tuple[int, int]) – tuple (Ap, Zp) of the projectile. Must be (1, 0) for neutron or (1, 1) for proton.
posterior (str) – Which KDUQ posterior to return samples from. Must be either "federal" or "democratic". Defaults to "federal".

Return type:

ndarray

Returns:

An array of shape (NUM_POSTERIOR_SAMPLES, num_params) containing the posterior samples for the given projectile.

jitr.optical_potentials.kduq.Vv(E, v1, v2, v3, v4, Ef)[source]¶

energy-dependent, volume-central strength - real term, Eq. (7)

Return type:

float

Parameters:

E (float)
v1 (float)
v2 (float)
v3 (float)
v4 (float)
Ef (float)

jitr.optical_potentials.kduq.Wv(E, w1, w2, Ef)[source]¶

energy-dependent, volume-central strength - imaginary term, Eq. (7)

Return type:

float

Parameters:

E (float)
w1 (float)
w2 (float)
Ef (float)

jitr.optical_potentials.kduq.Wd(E, d1, d2, d3, Ef)[source]¶

energy-dependent, surface-central strength - imaginary term (no real term), Eq. (7)

Return type:

float

Parameters:

E (float)
d1 (float)
d2 (float)
d3 (float)
Ef (float)

jitr.optical_potentials.kduq.Vso(E, vso1, vso2, Ef)[source]¶

energy-dependent, spin-orbit strength — real term, Eq. (7)

Return type:

float

Parameters:

E (float)
vso1 (float)
vso2 (float)
Ef (float)

jitr.optical_potentials.kduq.Wso(E, wso1, wso2, Ef)[source]¶

energy-dependent, spin-orbit strength — imaginary term, Eq. (7)

Return type:

float

Parameters:

E (float)
wso1 (float)
wso2 (float)
Ef (float)

jitr.optical_potentials.kduq.delta_VC(E, Vcbar, v1, v2, v3, v4, Ef)[source]¶

energy dependent Coulomb correction term, Eq. 23

Return type:

float

Parameters:

E (float)
Vcbar (float)
v1 (float)
v2 (float)
v3 (float)
v4 (float)
Ef (float)

jitr.optical_potentials.kduq.central(r, Vv, Rv, av, Wv, Rwv, awv, Wd, Rd, ad)[source]¶

Koning-Delaroche central terms at a given energy.

This matches Eq. (7) in Koning and Delaroche (2003).

Parameters:

r (float | ndarray) – The radius at which to evaluate the potential.
Vv (float) – The real central depth.
Rv (float) – The real central radius parameter.
av (float) – The real central diffuseness parameter.
Wv (float) – The imaginary volume depth.
Rwv (float) – The imaginary volume radius parameter.
awv (float) – The imaginary volume diffuseness parameter.
Wd (float) – The imaginary surface depth.
Rd (float) – The imaginary surface radius parameter.
ad (float) – The imaginary surface diffuseness parameter.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

jitr.optical_potentials.kduq.spin_orbit(r, Vso, Rso, aso, Wso, Rwso, awso)[source]¶

Koning-Delaroche spin-orbit terms at a given energy.

This matches Eq. (7) in Koning and Delaroche (2003).

Parameters:

r (float | ndarray) – The radius at which to evaluate the potential.
Vso (float) – The real spin-orbit depth.
Rso (float) – The real spin-orbit radius parameter.
aso (float) – The real spin-orbit diffuseness parameter.
Wso (float) – The imaginary spin-orbit depth.
Rwso (float) – The imaginary spin-orbit radius parameter.
awso (float) – The imaginary spin-orbit diffuseness parameter.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

class jitr.optical_potentials.kduq.Global(projectile, param_fpath=None)[source]¶

Bases: object

Global Koning-Delaroche parameters

Parameters:

projectile (tuple)
param_fpath (Path | None)

get_params(A, Z, Elab)[source]¶

Return Koning-Delaroche central, spin-orbit, and Coulomb parameters.

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Parameters:

A (int)
Z (int)
Elab (float)

jitr.optical_potentials.kduq.calculate_params(projectile, target, Elab, Ef_0, Ef_A, v1_0, v1_asymm, v1_A, v2_0, v2_A, v3_0, v3_A, v4_0, rv_0, rv_A, av_0, av_A, w1_0, w1_A, w2_0, w2_A, d1_0, d1_asymm, d2_0, d2_A, d2_A2, d2_A3, d3_0, rd_0, rd_A, ad_0, ad_A, Vso1_0, Vso1_A, Vso2_0, Wso1_0, Wso2_0, rso_0, rso_A, aso_0, rc_0=0.0, rc_A=0.0, rc_A2=0.0)[source]¶

Calculate the arguments for the central, spin_orbit, and coulomb_charged_sphere functions corresponding to the KDUQ potential for a given projectile, target, lab energy, and the KDUQ parameters.

Parameters:

projectile (tuple) – tuple (Ap, Zp) of the projectile.
target (tuple) – tuple (A, Z) of the target.
Elab (float) – Laboratory energy of the projectile in MeV.
Ef_0 (float) – Base Fermi energy.
Ef_A (float) – Atomic mass number modifier for Fermi energy.
v1_0 (float) – Parameters for the Koning-Delaroche potential. See Table V and the Appendix of Pruitt et al., 2023 for details.
v1_asymm (float) –
Parameters for the Koning-Delaroche potential. See Table V and the Appendix of Pruitt et al., 2023 for details.
... –
Parameters for the Koning-Delaroche potential. See Table V and the Appendix of Pruitt et al., 2023 for details.
rc_A2 (float) –
Parameters for the Koning-Delaroche potential. See Table V and the Appendix of Pruitt et al., 2023 for details.
v1_A (float)
v2_0 (float)
v2_A (float)
v3_0 (float)
v3_A (float)
v4_0 (float)
rv_0 (float)
rv_A (float)
av_0 (float)
av_A (float)
w1_0 (float)
w1_A (float)
w2_0 (float)
w2_A (float)
d1_0 (float)
d1_asymm (float)
d2_0 (float)
d2_A (float)
d2_A2 (float)
d2_A3 (float)
d3_0 (float)
rd_0 (float)
rd_A (float)
ad_0 (float)
ad_A (float)
Vso1_0 (float)
Vso1_A (float)
Vso2_0 (float)
Wso1_0 (float)
Wso2_0 (float)
rso_0 (float)
rso_A (float)
aso_0 (float)
rc_0 (float)
rc_A (float)

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Returns:

(central_params, spin_orbit_params, coulomb_params) where central_params is (vv, Rv, av, wv, Rwv, awv, wd, Rd, ad), spin_orbit_params is (vso, Rso, aso, wso, Rwso, awso), and coulomb_params is (Z*Zp, RC).

class jitr.optical_potentials.kduq.KDUQ(projectile)[source]¶

Bases: SingleChannelOpticalModel

Koning-Delaroche Uncertainty Quantification (KDUQ) optical potential model.

Parameters:: projectile (tuple)

evaluate(rgrid, reaction, kinematics, *params)[source]¶

Evaluate the KDUQ central, spin-orbit, and Coulomb terms.

Return type:

tuple[complex | ndarray[tuple[Any, ...], dtype[cdouble]], complex | ndarray[tuple[Any, ...], dtype[cdouble]], float | ndarray[tuple[Any, ...], dtype[double]]]

Parameters:

rgrid (float | ndarray)
reaction (Reaction)
kinematics (ChannelKinematics)
params (float)

The CHUQ potential is a global phenomenological nucleon-nucleus optical potential

See [Pruitt, et al., 2023] (https://journals.aps.org/prc/pdf/10.1103/PhysRevC.107.014602), or the original CH89 paper [Varner, et al., 1991] (https://www.sciencedirect.com/science/article/pii/037015739190039O?via%3Dihub) for details. Equation references are with respect to the former paper.

jitr.optical_potentials.chuq.get_param_names()[source]¶

Get the names of the parameters for the given projectile, in the order they are returned by get_ch89() and get_samples().

Return type:: list[str]

jitr.optical_potentials.chuq.get_ch89()[source]¶

Return the original CH89 frequentist parameter vector.

Return type:: ndarray
Returns:: A one-dimensional array containing the CH89 frequentist parameter set.

jitr.optical_potentials.chuq.get_samples(posterior='federal')[source]¶

Get the posterior samples for the given projectile (neutron or proton) from the CHUQ Federal or Democratic posteriors.

These samples are distinct from the original CH89 frequentist parameter set returned by get_ch89().

See [Pruitt, et al., 2023] (https://journals.aps.org/prc/pdf/10.1103/PhysRevC.107.014602) for details on the CHUQ posteriors.

Parameters:: posterior (str) – Which CHUQ posterior to return samples from. Must be either "federal" or "democratic". Defaults to "federal".
Return type:: ndarray
Returns:: An array of shape (NUM_POSTERIOR_SAMPLES, num_params) containing the posterior samples, ordered according to get_param_names().

jitr.optical_potentials.chuq.central(r, V, W, Wd, Rv, av, Rd, ad)[source]¶

Form of the central term of the CHUQ potential, given by Eqs. A7-8 of [Pruitt, et al., 2023]

Parameters:

r (float | ndarray) – The radius at which to evaluate the potential.
V (float) – The depth of the real central potential.
W (float) – The depth of the imaginary volume potential.
Wd (float) – The depth of the imaginary surface potential.
Rv (float) – The radius of the real central potential.
av (float) – The diffuseness of the real central potential.
Rd (float) – The radius of the imaginary potential.
ad (float) – The diffuseness of the imaginary potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

jitr.optical_potentials.chuq.spin_orbit(r, Vso, Rso, aso)[source]¶

Form of the spin-orbit term of the CHUQ potential, given by Eqs. A7-8 of [Pruitt, et al., 2023]

Parameters:

r (float | ndarray) – The radius at which to evaluate the potential.
Vso (float) – The depth of the spin-orbit potential.
Rso (float) – The radius of the spin-orbit potential.
aso (float) – The diffuseness of the spin-orbit potential.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

jitr.optical_potentials.chuq.calculate_params(projectile, target, Elab, V0=52.9, Ve=-0.299, Vt=13.1, r0=1.25, r0_0=-0.225, a0=0.69, Wv0=7.8, Wve0=35.0, Wvew=16.0, rw=1.33, rw_0=-0.42, aw=0.69, Ws0=10.0, Wst=18.0, Wse0=36.0, Wsew=37, Vso=5.9, rso=1.34, rso_0=-1.2, aso=0.63, rc=1.24, rc_0=0.12)[source]¶

Calculate the arguments for the central, spin_orbit, and coulomb_charged_sphere functions corresponding to the CHUQ potential for a given projectile, target, lab energy, and the CHUQ parameters.

Parameters:

projectile (tuple) – tuple (Ap, Zp) of the projectile.
target (tuple) – tuple (A, Z) of the target.
Elab (float) – Laboratory energy of the projectile in MeV.
V0 (float) – Parameters for the Chapel-Hill optical model potential. See Table V and the Appendix of Pruitt et al., 2023 and Table 3 of Varner et al., 1991 for details.
Ve (float) –
Parameters for the Chapel-Hill optical model potential. See Table V and the Appendix of Pruitt et al., 2023 and Table 3 of Varner et al., 1991 for details.
... –
Parameters for the Chapel-Hill optical model potential. See Table V and the Appendix of Pruitt et al., 2023 and Table 3 of Varner et al., 1991 for details.
rc_0 (float) –
Parameters for the Chapel-Hill optical model potential. See Table V and the Appendix of Pruitt et al., 2023 and Table 3 of Varner et al., 1991 for details.
Vt (float)
r0 (float)
r0_0 (float)
a0 (float)
Wv0 (float)
Wve0 (float)
Wvew (float)
rw (float)
rw_0 (float)
aw (float)
Ws0 (float)
Wst (float)
Wse0 (float)
Wsew (float)
Vso (float)
rso (float)
rso_0 (float)
aso (float)
rc (float)

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Returns:

(central_params, spin_orbit_params, coulomb_params) where central_params is (V0, Wv, Ws, R0, a0, Rw, aw), spin_orbit_params is (Vso, Rso, aso), and coulomb_params is (Z*Zp, RC).

jitr.optical_potentials.chuq.coulomb_correction(A, Z, RC)[source]¶

Coulomb correction for proton energy

Return type:

float

Parameters:

A (int)
Z (int)
RC (float)

class jitr.optical_potentials.chuq.Global(param_fpath=None)[source]¶

Bases: object

Global optical potential in CHUQ form.

Parameters:: param_fpath (Path | None)

get_params(projectile, target, Elab)[source]¶

Return CHUQ central, spin-orbit, and Coulomb parameters.

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Parameters:

projectile (tuple[int, int])
target (tuple[int, int])
Elab (float)

class jitr.optical_potentials.chuq.CHUQ[source]¶

Bases: SingleChannelOpticalModel

Chapel-Hill Uncertainty Quantification (CHUQ) optical potential model.

Note that CH89 is Lane consistent, so the same parameters can be used for both neutron and proton projectiles.

evaluate(rgrid, reaction, kinematics, *params)[source]¶

Evaluate the CHUQ central, spin-orbit, and Coulomb terms.

Return type:

Parameters:

rgrid (float | ndarray)
reaction (Reaction)
kinematics (ChannelKinematics)
params (float)

The Whitehead-Lim-Holt potential is a global mcroscopic nucleon-nucleus optical potential

See the [Whitehead et al., 2021] (https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.182502) for details. Equation references are with respect to (w.r.t.) this paper.

jitr.optical_potentials.wlh.get_param_names(projectile)[source]¶

Get the names of the parameters for the given projectile, in the order they are returned by the get_samples function.

Return type:: list[str]
Parameters:: projectile (tuple[int, int])

jitr.optical_potentials.wlh.get_samples(projectile)[source]¶

Get the parameter samples for the WLH potential for the given projectile.

Parameters:: projectile (tuple[int, int]) – tuple (A, Z) of the projectile. Should be (1, 0) for neutron and (1, 1) for proton.
Return type:: ndarray

jitr.optical_potentials.wlh.spin_orbit(r, Uso, Rso, aso)[source]¶

Form of the spin-orbit term in the WLH potential. See Eq. (2) of Whitehead et al., 2021.

Parameters:

r (float | ndarray) – Radial coordinate(s) at which to evaluate the potential.
Uso (float) – Spin-orbit strength parameter.
Rso (float) – Spin-orbit radius parameter.
aso (float) – Spin-orbit diffuseness parameter.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

jitr.optical_potentials.wlh.central(r, Uv, Rv, av, Uw, Rw, aw, Ud, Rd, ad)[source]¶

Form of the central term in the WLH potential. See Eq. (2) of Whitehead et al., 2021.

Parameters:

r (float | ndarray) – Radial coordinate(s) at which to evaluate the potential.
Uv (float) – Real volume potential strength parameter.
Rv (float) – Real volume potential radius parameter.
av (float) – Real volume potential diffuseness parameter.
Uw (float) – Imaginary volume potential strength parameter.
Rw (float) – Imaginary volume potential radius parameter.
aw (float) – Imaginary volume potential diffuseness parameter.
Ud (float) – Imaginary surface potential strength parameter.
Rd (float) – Imaginary surface potential radius parameter.
ad (float) – Imaginary surface potential diffuseness parameter.

Return type:

complex | ndarray[tuple[Any, ...], dtype[cdouble]]

class jitr.optical_potentials.wlh.Global(projectile, param_fpath=None)[source]¶

Bases: object

Global optical potential in WLH form.

Parameters:

projectile (tuple)
param_fpath (Path | None)

get_params(A, Z, Elab)[source]¶

Return WLH central, spin-orbit, and Coulomb parameters.

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Parameters:

A (int)
Z (int)
Elab (float)

jitr.optical_potentials.wlh.calculate_params(projectile, target, Elab, uv0, uv1, uv2, uv3, uv4, uv5, uv6, rv0, rv1, rv2, rv3, av0, av1, av2, av3, av4, uw0, uw1, uw2, uw3, uw4, rw0, rw1, rw2, rw3, rw4, rw5, aw0, aw1, aw2, aw3, aw4, ud0, ud1, ud3, ud4, rd0, rd1, rd2, ad0, uso0, uso1, rso0, rso1, aso0, aso1)[source]¶

Calculate the arguments for the central, spin_orbit, and coulomb_charged_sphere functions corresponding to the WLH potential for a given projectile, target, lab energy, and the WLH parameters.

Parameters:

projectile (tuple) – tuple (A, Z) of the projectile.
target (tuple) – tuple (A, Z) of the target.
Elab (float) – Laboratory energy in MeV.
uv0 (float) – Parameters of the WLH potential. See Whitehead et al., 2021 for details.
uv1 (float) –
Parameters of the WLH potential. See Whitehead et al., 2021 for details.
... –
Parameters of the WLH potential. See Whitehead et al., 2021 for details.
aso1 (float) –
Parameters of the WLH potential. See Whitehead et al., 2021 for details.
uv2 (float)
uv3 (float)
uv4 (float)
uv5 (float)
uv6 (float)
rv0 (float)
rv1 (float)
rv2 (float)
rv3 (float)
av0 (float)
av1 (float)
av2 (float)
av3 (float)
av4 (float)
uw0 (float)
uw1 (float)
uw2 (float)
uw3 (float)
uw4 (float)
rw0 (float)
rw1 (float)
rw2 (float)
rw3 (float)
rw4 (float)
rw5 (float)
aw0 (float)
aw1 (float)
aw2 (float)
aw3 (float)
aw4 (float)
ud0 (float)
ud1 (float)
ud3 (float)
ud4 (float)
rd0 (float)
rd1 (float)
rd2 (float)
ad0 (float)
uso0 (float)
uso1 (float)
rso0 (float)
rso1 (float)
aso0 (float)

Return type:

tuple[tuple[float, ...], tuple[float, ...], tuple[float, ...]]

Returns:

(central_params, spin_orbit_params, coulomb_params) where central_params is (uv, Rv, av, uw, Rw, aw, ud, Rd, ad), spin_orbit_params is (uso, Rso, aso), and coulomb_params is (Z*Zp, RC).

class jitr.optical_potentials.wlh.WLH(projectile)[source]¶

Bases: SingleChannelOpticalModel

The Whitehead-Lim-Holt global optical potential for nucleon-nucleus scattering.

Parameters:: projectile (tuple)

evaluate(rgrid, reaction, kinematics, *params)[source]¶

Evaluate the central, spin-orbit, and Coulomb terms of the WLH potential on the given radial grid for the specified reaction and kinematics, using the provided potential parameters.

Parameters:

rgrid (float | ndarray[tuple[Any, ...], dtype[double]]) – Radial coordinate or grid in fm.
reaction (Reaction) – Reaction for which to calculate the parameters.
kinematics (ChannelKinematics) – Kinematics of the reaction channel.
*params (float) –
Parameters of the WLH potential. See Whitehead et al., 2021 for details.

Return type:

Returns: