pynucastro.rates.tabular_rate module

pynucastro.rates.tabular_rate module#

Classes and methods for describing a reaction rate that is tabulated in terms of electron density and temperature.

class pynucastro.rates.tabular_rate.TableIndex(*values)[source]#

Bases: Enum

An enum-like container for indexing the electron-capture tables.

DQ = 3#
GAMMA = 7#
MU = 2#
NU = 6#
RATE = 5#
RHOY = 0#
T = 1#
VS = 4#
class pynucastro.rates.tabular_rate.TableInterpolator(*args, **kwargs)[source]#

Bases: TableInterpolator

A class that holds a pointer to the table data and methods that allow us to interpolate a variable

Parameters:

  • table_rhoy_lines (int) – the number of the (ρ Y_e) values where the rate is tabulated

  • table_temp_lines (int) – the number of T values where the rate is tabulated

  • table_data (numpy.ndarray) – a 2D array giving the tabulated rate data of the form (index, component) where index is a 1D flattened representation of (rhoY, T).

class_type = jitclass.TableInterpolator#7fe906e35a30<data:array(float64, 2d, A),table_rhoy_lines:int32,table_temp_lines:int32,rhoy:array(float64, 1d, A),temp:array(float64, 1d, A)>#
class pynucastro.rates.tabular_rate.TabularRate(*args, **kwargs)[source]#

Bases: TabularWeakRate

A rate tabulated in terms of log10(ρ Y_e) and log10(T).

Deprecated since version 3.0: TabularRate has been deprecated. Use TabularWeakRate instead. TabularRate will be removed in version 3.1.

Parameters:

rfile (str, pathlib.Path, io.StringIO) – the file containing the data table

class pynucastro.rates.tabular_rate.TabularWeakRate(rfile=None)[source]#

Bases: Rate

A rate tabulated in terms of log10(ρ Y_e) and log10(T).

Parameters:

rfile (str, pathlib.Path, io.StringIO) – the file containing the data table

eval_jacobian_term(state, y_i, *, screen_func=None)[source]#

Evaluate ∂flux/∂(y_i), the derivative of the rate with respect to y_i. This flux term has the full composition dependence, i.e., for a decay rate:

flux = Y(p) λ(ρY_e, T)

where p is the parent nucleus. Note that there are 2 contributions,

∂flux/∂(y_i) = δ_{ip} λ + Y(p) ρ ∂λ/∂(ρY_e) Z_i

where we used ∂Y_e/∂Y_i = Z_i

Parameters:

  • state (ThermoState) – ThermoState containing relevant thermodynamic information used to evaluate rates. It knows about (rho, T, composition).

  • y_i (Nucleus) – the nucleus we are differentiating with respect to

  • screen_func (Callable) – Screening doesn’t apply for electron-capture / decay rates, but we include the argument here to ensure the interface is standard.

Return type:

float

function_string_cxx(dtype='double', specifiers='inline', leave_open=False, extra_args=None)[source]#

Return a string containing the C++ function that computes the rate

Parameters:

  • dtype (str) – The C++ datatype to use for all declarations

  • specifiers (str) – C++ specifiers to add before each function declaration (i.e. “inline”)

  • leave_open (bool) – If true, then we leave the function unclosed (no “}” at the end). This can allow additional functions to add to this output.

  • extra_args (list, tuple) – A list of strings representing additional arguments that should be appended to the argument list when defining the function interface.

Return type:

str

function_string_py()[source]#

Construct the python function that computes the rate.

Return type:

str

get_drate_drhoye(state)[source]#

Evaluate the ∂λ/∂(ρY_e) for the rate.

Parameters:

state (ThermoState) – ThermoState containing relevant thermodynamic information used to evaluate the rate derivative loss. It knows about (rho, T, composition).

Return type:

float

get_nu_loss(state)[source]#

Evaluate the neutrino loss for the rate.

Parameters:

state (ThermoState) – ThermoState containing relevant thermodynamic information used to evaluate neutrino loss. It knows about (rho, T, composition).

Return type:

float

log_eval(T, *, rho=None, comp=None, screen_func=None)[source]#

Evaluate the natural log of the reaction rate.

Parameters:

  • T (float) – the temperature to evaluate the rate at

  • rho (float) – the density to evaluate the rate at.

  • comp (float) – the composition (of type Composition) to evaluate the rate with.

  • screen_func (Callable) – one of the screening functions from pynucastro.screening – if provided, then the rate will include screening correction. Unused for Tabular weak rates since screening does not affect weak reactions.

Return type:

float

plot(*, Tmin=None, Tmax=None, rhoYmin=None, rhoYmax=None, color_field='rate', figsize=(10, 10))[source]#

Plot the rate or neutrino loss in the log10(ρ Y_e) and log10(T) plane.

Parameters:

  • Tmin (float) – minimum temperature for the plot

  • Tmax (float) – maximum temperature for the plot

  • rhoYmin (float) – minimum (ρ Y_e) for the plto

  • rhoYmax (float) – maximum (ρ Y_e) for the plto

  • color_field (str) – the field to plot. Possible values are “rate” or “nu_loss”

  • figsize (tuple) – the horizontal, vertical size (in inches) for the plot

Return type:

matplotlib.figure.Figure