Stray light evaluation for the astrometric gravitation probe mission

Federico Landini; Alberto Riva; Mario Gai; Cristian Baccani; Mauro Focardi; Maurizio Pancrazzi

doi:10.1117/12.2232568

4 August 2016 Stray light evaluation for the astrometric gravitation probe mission

Federico Landini, Alberto Riva, Mario Gai, Cristian Baccani, Mauro Focardi, Maurizio Pancrazzi

Proceedings Volume 9907, Optical and Infrared Interferometry and Imaging V; 990741 (2016) https://doi.org/10.1117/12.2232568
Event: SPIE Astronomical Telescopes + Instrumentation, 2016, Edinburgh, United Kingdom

Abstract

The main goal of the Astrometric Gravitation Probe mission is the verification of General Relativity and competing gravitation theories by precise astrometric determination of light deflection, and of orbital parameters of selected Solar System objects. The key element is the coherent combination of a set of 92 circular entrance apertures, each feeding an elementary inverted occulter similar to the one developed for Solar Orbiter/METIS.¹ This provides coronagraphic functions over a relevant field of view, in which all stars are observed for astrometric purposes with the full resolution of a 1 m diameter telescope. The telescope primary mirror acts as a beam combiner, feeding the 92 pupils, through the internal optics, toward a single focal plane. The primary mirror is characterized by 92 output apertures, sized according to the entrance pupil and telescope geometry, in order to dump the solar disk light beyond the instrument. The astronomical objects are much fainter than the solar disk, which is angularly close to the inner field of view of the telescope. The stray light as generated by the diffraction of the solar disk at the edges of the 92 apertures defines the limiting magnitude of observable stars. In particular, the stray light due to the diffraction from the pupil apertures is scattered by the telescope optics and follows the same optical path of the astronomical objects; it is a contribution that cannot be eliminated and must therefore be carefully evaluated. This paper describes the preliminary evaluation of this stray light contribution.

Citation Download Citation

Federico Landini, Alberto Riva, Mario Gai, Cristian Baccani, Mauro Focardi, and Maurizio Pancrazzi "Stray light evaluation for the astrometric gravitation probe mission", Proc. SPIE 9907, Optical and Infrared Interferometry and Imaging V, 990741 (4 August 2016); https://doi.org/10.1117/12.2232568

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available