G03_LMCAvg

class dust_extinction.averages.G03_LMCAvg(*args, meta=None, name=None, **kwargs)

Bases: BaseExtModel

Gordon et al (2003) LMCAvg Average Extinction Curve

Parameters:

None

Raises:

None

Notes

From Gordon et al. (2003, ApJ, 594, 279)

Example showing the average curve

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

from dust_extinction.averages import G03_LMCAvg

fig, ax = plt.subplots()

# define the extinction model
ext_model = G03_LMCAvg()

# generate the curves and plot them
x = np.arange(ext_model.x_range[0], ext_model.x_range[1],0.1)/u.micron

ax.plot(x,ext_model(x),label='G03 LMCAvg')
ax.plot(ext_model.obsdata_x, ext_model.obsdata_axav, 'ko',
        label='obsdata')

ax.set_xlabel(r'$x$ [$\mu m^{-1}$]')
ax.set_ylabel(r'$A(x)/A(V)$')

# for 2nd x-axis with lambda values
axis_xs = np.array([0.1, 0.12, 0.15, 0.2, 0.3, 0.5, 1.0])
new_ticks = 1 / axis_xs
new_ticks_labels = ["%.2f" % z for z in axis_xs]
tax = ax.twiny()
tax.set_xlim(ax.get_xlim())
tax.set_xticks(new_ticks)
tax.set_xticklabels(new_ticks_labels)
tax.set_xlabel(r"$\lambda$ [$\mu$m]")

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

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

Attributes Summary

Rv
obsdata_axav
obsdata_tolerance
obsdata_x
x_range

Methods Summary

evaluate(in_x)

G03 LMCAvg function

Attributes Documentation

Rv = 3.41

obsdata_axav = array([0.1  , 0.186, 0.257, 1.   , 1.293, 1.518, 1.786, 1.969, 2.149,        2.391, 2.771, 2.967, 2.846, 2.646, 2.565, 2.566, 2.598, 2.607,        2.668, 2.787, 2.874, 2.983, 3.118, 3.231, 3.374, 3.366])

obsdata_tolerance = 0.06

obsdata_x = array([0.455, 0.606, 0.8  , 1.818, 2.273, 2.703, 3.375, 3.625, 3.875,        4.125, 4.375, 4.625, 4.875, 5.125, 5.375, 5.625, 5.875, 6.125,        6.375, 6.625, 6.875, 7.125, 7.375, 7.625, 7.875, 8.125])

x_range = [0.3, 10.0]

Methods Documentation

evaluate(in_x)

G03 LMCAvg 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