scopesim.effects.shifts.atmospheric_refraction

scopesim.effects.shifts.atmospheric_refraction#

scopesim.effects.shifts.atmospheric_refraction(lam, z0=60, temp=0, rel_hum=60, pres=750, lat=-24.5, h=3064)#

Compute atmospheric refraction.

The function computes the angular difference between the apparent position of a star seen from the ground and its true position.

Parameters:
  • lam (float, np.ndarray) – [um] wavelength bin centres

  • z0 (float, optional) – [deg] zenith distance. Default is 60 deg from zenith

  • temp (float, optional) – [deg C] ground temperature. Default is 0 deg C

  • rel_hum (float, optional) – [%] relative humidity. Default is 60%

  • pres (float, optional) – [millibar] air pressure. Default is 750 mbar

  • lat (float, optional) – [deg] latitude. Default set for Cerro Armazones: 24.5 deg South

  • h (float, optional) – [m] height above sea level. Default is 3064 m

Returns:

ang – [arcsec] angle between real position and refracted position

Return type:

float, np.ndarray

References

See Stone 1996 and the review by S. Pedraz - http://www.caha.es/newsletter/news03b/pedraz/newslet.html