detray::interaction< scalar_t > Struct Template Reference

Computes energy loss and multiple scattering in detector material. More...

#include <detray/material/interaction.hpp>

Inheritance diagram for detray::interaction< scalar_t >:

Public Types
using	relativistic_quantities = detail::relativistic_quantities<scalar_type>
	Cached particle kinematics used by the interaction formulas.
using	scalar_type = scalar_t
	Scalar type used by the interaction calculations.

Public Member Functions
scalar_type	compute_bethe_bloch (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &, const relativistic_quantities &rq) const
	Compute the collisional stopping power from the Bethe–Bloch expression.
scalar_type	compute_bremsstrahlung (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Estimate electron or positron radiative stopping power using Rossi’s approximation.
scalar_type	compute_energy_loss_bethe_bloch (const scalar_type path_segment, const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Compute the collisional energy loss over a path segment.
scalar_type	compute_energy_loss_landau (const scalar_type path_segment, const material< scalar_type > &mat, const pdg_particle< scalar_type > &, const relativistic_quantities &rq) const
	Compute the most-probable energy loss using the Landau approximation.
scalar_type	compute_energy_loss_landau_fwhm (const scalar_type path_segment, const material< scalar_type > &mat, const pdg_particle< scalar_type > &, const relativistic_quantities &rq) const
	Compute the Landau energy-loss distribution full width at half maximum.
scalar_type	compute_energy_loss_landau_sigma (const scalar_type path_segment, const material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Convert the Landau width to a Gaussian-equivalent energy-loss sigma.
template<typename material_t>
scalar_type	compute_energy_loss_landau_sigma_QOverP (const scalar_type path_segment, const material_t &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Convert energy-loss sigma to a q/p uncertainty.
scalar_type	compute_multiple_scattering_theta0 (const scalar_type xOverX0, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Estimate the projected multiple-scattering angle for a material thickness.
scalar_type	compute_stopping_power (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Sum collisional and radiative stopping-power contributions.
scalar_type	derive_bethe_bloch (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Differentiate the Bethe–Bloch stopping power with respect to q/p.
scalar_type	derive_bremsstrahlung (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Differentiate the bremsstrahlung stopping power with respect to q/p.
scalar_type	derive_stopping_power (const detray::material< scalar_type > &mat, const pdg_particle< scalar_type > &ptc, const relativistic_quantities &rq) const
	Differentiate the total stopping power with respect to q/p.

Detailed Description

template<concepts::scalar scalar_t>
struct detray::interaction< scalar_t >

Computes energy loss and multiple scattering in detector material.

Member Function Documentation

compute_bethe_bloch()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_bethe_bloch	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	,
		const relativistic_quantities &	rq ) const

Compute the collisional stopping power from the Bethe–Bloch expression.

Parameters

mat	material traversed by the particle
rq	cached relativistic quantities for the particle

Returns

computed interaction quantity in the corresponding units

compute_bremsstrahlung()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_bremsstrahlung	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Estimate electron or positron radiative stopping power using Rossi’s approximation.

Parameters

mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

computed interaction quantity in the corresponding units

compute_energy_loss_bethe_bloch()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_energy_loss_bethe_bloch	(	const scalar_type	path_segment,
		const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Compute the collisional energy loss over a path segment.

Parameters

path_segment	distance travelled in the material
mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

computed interaction quantity in the corresponding units

compute_energy_loss_landau()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_energy_loss_landau	(	const scalar_type	path_segment,
		const material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	,
		const relativistic_quantities &	rq ) const

Compute the most-probable energy loss using the Landau approximation.

Parameters

path_segment	distance travelled in the material
mat	material traversed by the particle
rq	cached relativistic quantities for the particle

Returns

most-probable energy loss for the segment

compute_energy_loss_landau_fwhm()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_energy_loss_landau_fwhm	(	const scalar_type	path_segment,
		const material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	,
		const relativistic_quantities &	rq ) const

Compute the Landau energy-loss distribution full width at half maximum.

Parameters

path_segment	distance travelled in the material
mat	material traversed by the particle
rq	cached relativistic quantities for the particle

Returns

full width at half maximum of the energy-loss distribution

compute_energy_loss_landau_sigma()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_energy_loss_landau_sigma	(	const scalar_type	path_segment,
		const material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Convert the Landau width to a Gaussian-equivalent energy-loss sigma.

Parameters

path_segment	distance travelled in the material
mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

Gaussian-equivalent standard deviation of the energy loss

compute_energy_loss_landau_sigma_QOverP()

template<concepts::scalar scalar_t>

template<typename material_t>

scalar_type detray::interaction< scalar_t >::compute_energy_loss_landau_sigma_QOverP	(	const scalar_type	path_segment,
		const material_t &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Convert energy-loss sigma to a q/p uncertainty.

Parameters

path_segment	distance travelled in the material
mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

standard deviation in q/p units

compute_multiple_scattering_theta0()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_multiple_scattering_theta0	(	const scalar_type	xOverX0,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Estimate the projected multiple-scattering angle for a material thickness.

Parameters

xOverX0	material thickness in radiation lengths
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

computed interaction quantity in the corresponding units

compute_stopping_power()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::compute_stopping_power	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Sum collisional and radiative stopping-power contributions.

Parameters

mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

computed interaction quantity in the corresponding units

derive_bethe_bloch()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::derive_bethe_bloch	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Differentiate the Bethe–Bloch stopping power with respect to q/p.

Returns

computed derivative in the corresponding units Differentiate Bethe–Bloch stopping power with respect to q/p.

Parameters

mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

derivative of stopping power with respect to q/p

derive_bremsstrahlung()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::derive_bremsstrahlung	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Differentiate the bremsstrahlung stopping power with respect to q/p.

Parameters

mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

computed derivative in the corresponding units

derive_stopping_power()

template<concepts::scalar scalar_t>

scalar_type detray::interaction< scalar_t >::derive_stopping_power	(	const detray::material< scalar_type > &	mat,
		const pdg_particle< scalar_type > &	ptc,
		const relativistic_quantities &	rq ) const

Differentiate the total stopping power with respect to q/p.

Returns

computed derivative in the corresponding units Differentiate total stopping power with respect to q/p.

Parameters

mat	material traversed by the particle
ptc	particle hypothesis
rq	cached relativistic quantities for the particle

Returns

derivative of stopping power with respect to q/p