D22¶

class dust_extinction.parameter_averages.D22(Rv=3.1, **kwargs)[source]¶

Bases: BaseExtRvModel

Decleir et al (2022) extinction model calculation

Decleir, Gordon, et al. (2022, ApJ, submitted) model. Based on a sample of stars observed spectroscopically in the NIR with IRTF/SpeX.

Parameters:

Rv: float: R(V) = A(V)/E(B-V) = total-to-selective extinction

Raises:

InputParameterError: Input Rv values outside of defined range

Notes

D22 Milky Way R(V) dependent extinction model

Example showing D22 curves for a range of R(V) values.

import numpy as np
import matplotlib.pyplot as plt
import astropy.units as u

from dust_extinction.parameter_averages import D22

fig, ax = plt.subplots()

# temp model to get the correct x range
text_model = D22()

# generate the curves and plot them
x = np.arange(text_model.x_range[0], text_model.x_range[1], 0.01) / u.micron

Rvs = [2.5, 3.1, 4.0, 4.75, 5.5]
for cur_Rv in Rvs:
    ext_model = D22(Rv=cur_Rv)
    ax.plot(1. / x, ext_model(x), label="R(V) = " + str(cur_Rv))

ax.set_xlabel(r"$\lambda$ [$\mu m$]")
ax.set_ylabel(r"$A(x)/A(V)$")

ax.legend(loc="best")
plt.show()

(Source code, png, hires.png, pdf)

../_images/dust_extinction-parameter_averages-D22-1.png

Attributes Summary

`Rv_range`
`x_range`

Methods Summary

evaluate(in_x, Rv)

D22 function

Attributes Documentation

Rv_range = [2.5, 5.5]¶

x_range = [0.25, 1.25]¶

Methods Documentation

evaluate(in_x, Rv)[source]¶

D22 function

Parameters:

in_x: float

expects either x in units of wavelengths or frequency or assumes wavelengths in wavenumbers [1/micron]

internally wavenumbers are used

Returns:

axav: np array (float): A(x)/A(V) extinction curve [mag]

Raises:

ValueError: Input x values outside of defined range

Navigation

D22¶