reactions

class reactions.Reaction(name, in_states, out_states, alpha, beta, gamma, spline_data=None, frwrd_rate_param_func=None, interp_type=None)[source]

Bases: Module

Nuclear reaction.

name

Name of the reaction.

Type:

str

in_states

Particles on the LHS of the reaction. Convention is 0:n, 1:p, 2:d, 3:t, 4:He3, 5:a, 6:Li7, 7:Be7, 8: He6, 9: Li6, 10: Li8, 11:B8.

Type:

tuple

out_states

Particles on the RHS of the reaction.

Type:

tuple

frwrd_symmetry_fac

Symmetry factor associated with forward direction.

Type:

float

bkwrd_symmetry_fac

Symmetry factor associated with backward direction.

Type:

float

alpha

Coefficient for relation between forward and backward reaction. Dimensionful.

Type:

float

beta

Coefficient, same as above, dimensionless.

Type:

float

gamma

Coefficient, same as above, dimensionless.

Type:

float

T9_vec

(T/10^9 K), abscissa for reaction rate parameter with spline fit.

Type:

list

mu_median_vec

Median reaction rate parameter with spline fit.

Type:

list

expsigma_vec

Exponential uncertainty of reaction rate parameter with spline fit.

Type:

list

interp_type

Interpolation for spline fit. Either ‘linear’ or ‘log’.

Type:

str

frwrd_rate_param_func

Forward rate parameter function, if no spline fit.

Type:

callable

Notes

The rate functions are either <sigma v> or <sigma v^2> divided by (1 amu)^(N_in-1)) for each reaction, units (cm^3/s/g or cm^6/s/g^2).

bkwrd_rate_param(T, p)[source]

Backward rate parameter.

Parameters:
  • T (float) – Temperature in K.

  • p (float) – Rescaling parameter for expsigma.

  • interp_type (str, optional) – Interpolation type for spline data. Either ‘linear’ or ‘log’.

Return type:

float

Notes

We take log(<sigma v>) = log(mu) + p*log(expsigma), where p follows a Gaussian distribution, or equivalently <sigma v> = mu * exp(p*log(expsigma)).

The rate here is either <sigma v> or <sigma v^2> divided by (1 amu)^(N_in-1)) for each reaction, units (cm^3/s/g or cm^6/s/g^2).

frwrd_rate_param(T, p)[source]

Forward rate parameter.

Parameters:
  • T (float) – Temperature in K.

  • p (float) – Rescaling parameter for expsigma.

  • interp_type (str, optional) – Interpolation type for spline data. Either ‘linear’ or ‘log’.

Return type:

float

Notes

We take log(<sigma v>) = log(mu) + p*log(expsigma), where p follows a Gaussian distribution, or equivalently <sigma v> = mu * exp(p*log(expsigma)).

The rate here is either <sigma v> or <sigma v^2> divided by (1 amu)^(N_in-1)) for each reaction, units (cm^3/s/g or cm^6/s/g^2).