Telescopes, Planets, and Stars

The coronagraph model relies on numerous parameters describing the telescope, planet, and star used for each calculation. Below Telescope, Planet, and Star classes are listed, which can be instantiated and passed along to noise calculations.

class coronagraph.teleplanstar.Telescope(mode='IFS', lammin=0.3, lammax=2.0, R=70.0, Tput=0.2, D=8.0, Tsys=260.0, Tdet=50.0, IWA=0.5, OWA=30000.0, emis=0.9, C=1e-10, De=0.0001, DNHpix=3.0, Re=0.1, Rc=0.0, Dtmax=1.0, X=0.7, q=0.9, filter_wheel=None, aperture='circular', A_collect=None, Tput_lam=None, qe_lam=None, lammin_lenslet=None, diam_circumscribed=None, diam_inscribed=None, lam=None, dlam=None)

A class to represent a telescope object and all design specifications therein

Parameters:
  • mode (str) – Telescope observing modes: ‘IFS’, ‘Imaging’
  • lammin (float) – Minimum wavelength (um)
  • lammax (float) – Maximum wavelength (um)
  • R (float) – Spectral resolution (lambda / delta-lambda)
  • Tsys (float) – Telescope temperature (K)
  • D (float) – Telescope diameter (m)
  • emis (float) – Telescope emissivity
  • IWA (float) – Inner Working Angle (lambda/D)
  • OWA (float) – Outer Working Angle (lambda/D)
  • Tput (float) – Telescope throughput
  • C (float) – Raw Contrast
  • De (float) – Dark current (s**-1)
  • DNHpix (float) – Horizontal pixel spread of IFS spectrum
  • Re (float) – Read noise per pixel
  • Rc (float, optional) – Clock induced charge [counts/pixel/photon]
  • Dtmax (float) – Maximum exposure time (hr)
  • X (float) – Size of photometric aperture (lambda/D)
  • q (float) – Quantum efficiency
  • filter_wheel (Wheel (optional)) – Wheel object containing imaging filters
  • aperture (str) – Aperture type (“circular” or “square”)
  • A_collect (float) – Mirror collecting area (m**2) if different than \(\pi(D/2)^2\)
  • diam_circumscribed (float, optional) – Circumscribed telescope diameter [m] used for IWA and OWA (uses diam if None provided)
  • diam_inscribed (float, optional) – Inscribed telescope diameter [m] used for lenslet calculations (uses diam if None provided)
  • Tput_lam (tuple of arrays) – Wavelength-dependent throughput e.g. (wls, tputs). Note that if Tput_lam is used the end-to-end throughput will equal the convolution of Tput_lam[1] with Tput.
  • qe_lam (tuple of arrays) – Wavelength-dependent throughput e.g. (wls, qe). Note that if qe_lam is used the total quantum efficiency will equal the convolution of qe_lam[1] with q.
  • lammin_lenslet (float, optional) – Minimum wavelength to use for lenslet calculation (default is lammin)
  • lam (array-like, optional) – Wavelength grid for spectrograph [microns] (uses lammin, lammax, and resolution to determine if None provided)
  • dlam (array-like, optional) – Wavelength grid widths for spectrograph [microns] (uses lammin, lammax, and resolution to determine if None provided)
default_luvoir()

Initialize telescope object using current LUVOIR parameters (Not decided!)

default_habex()

Initialize telescope object using current HabEx parameters (Not decided!)

default_wfirst()

Initialize telescope object using current WFIRST parameters (Not decided!)

classmethod default_luvoir()
classmethod default_habex()
classmethod default_wfirst()
mode
filter_wheel
class coronagraph.teleplanstar.Planet(name='earth', star='sun', d=10.0, Nez=1.0, Rp=1.0, a=1.0, alpha=90.0, MzV=23.0, MezV=22.0)

A class to represent a planet and all associated parameters of the planet to be observed.

Parameters:
  • name (string) – Planet name from database
  • star (string) – Stellar type of planet host star
  • d (float) – Distance to system (pc)
  • Nez (float) – Number of exzodis (zodis)
  • Rp (float) – Radius of planet (Earth Radii)
  • a (float) – Semi-major axis (AU)
  • alpha (float) – Phase angle (deg)
  • Phi (float) – Lambertian phase function
  • MzV (float) – Zodiacal light surface brightness (mag/arcsec**2)
  • MezV (float) – exozodiacal light surface brightness (mag/arcsec**2)
from_file()

Initialize object using planet parameters in the Input file

alpha
Phi
class coronagraph.teleplanstar.Star(Teff=5780.0, Rs=1.0)

A class to represent the stellar host for an exoplanet observation

Parameters:
  • Teff (float) – Stellar effective temperature [K]
  • Rs (float) – Stellar radius [Solar Radii]