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GrismTheta - Angle between normal to detector plane and reference ray

Description:
This attribute gives the angle of incidence of light of the reference wavelength (given by attribute GrismWaveR) onto the detector. Specifically, it holds the angle (in radians) between the normal to the detector plane and an incident ray at the reference wavelength. The default value is 0.0.
Type:
Double precision.
Class Applicability:
GrismMap
All GrismMaps have this attribute.


next up previous 264
Next: GrismWaveR - The reference wavelength
Up: AST Attribute Descriptions
Previous: GrismNRP - The rate of change of refractive index with wavelength

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council