SkyBackground

class m4opt.synphot.background.SkyBackground

Bases: object

Sky Brightness background: sky glow due to scattered and diffuse light

Currently, only the Kitt Peak sky brightness observations from Neugent and Massey (2010) [1] are supported. There are four methods, sampling a selection of sky brightness conditions:

• low(): At zenith in June

• medium() : At zenith in February

• high(): At a zenith angle of 60 degrees towards Phoenix

• veryhigh(): At a zenith angle of 60 degrees towards Tucson

Notes

Spectra are given only for B and V bands (~3750 - ~6875 Angstrom) and do not include effect of lunar phase.

References

[1]

Neugent, K. and Massey, P., 2010, “The Spectrum of the Night Sky Over Kitt Peak: Changes Over Two Decades”. PASP, 122, 1246-1253 doi:10.1086/656425

Examples

>>> from astropy import units as u
>>> from m4opt.synphot.background import SkyBackground

>>> background = SkyBackground.low()
>>> background(5890 * u.angstrom, flux_unit=u.ABmag)
<Magnitude 20.66945113 mag(AB)>

>>> background = SkyBackground.veryhigh()
>>> background(5890 * u.angstrom, flux_unit=u.ABmag)
<Magnitude 19.09920111 mag(AB)>

from astropy import units as u
from astropy.visualization import quantity_support
from matplotlib import pyplot as plt
import numpy as np

from m4opt.synphot.background import SkyBackground

quantity_support()

wave = np.linspace(3750, 6868) * u.angstrom
ax = plt.axes()
for key in ['veryhigh', 'high', 'medium', 'low']:
    surf = getattr(SkyBackground, key)()(wave, flux_unit=u.ABmag)
    ax.plot(wave, surf, label=f'SkyBackground.{key}')
ax.legend()
ax.invert_yaxis()

(Source code)

Sky background spectra

Methods Summary

high()
low()
medium()
veryhigh()

Methods Documentation

static high()

static low()

static medium()

static veryhigh()