Memos and presentations

PRIMA/ESPRI

Report on compensating for flexure in the VLT Auxiliary Telescopes
Released to the ESPRI Consortium on 21 Dec 2012
PRIMA (Phase-referenced imaging and microarsec astrometry) was an instrument at ESO’s Very Large Telescope Interferometer. It required an advanced metrology system to precisely monitor the optical path difference between two of the 2.4-meter Auxiliary Telescopes at Paranal Observatory. In this report, I combined a Zemax model of the ATs with a simple model of a wavefront sensor to show how we could relate sensed aberrations to the structural flexure between mirrors M1 and M2.

Constraints on the astrometric bias of PRIMA
Released to the ESPRI consortium on 8 Mar 2012
During one of the PRIMA commissioning runs at Paranal Observatory, the ESPRI (Extrasolar planet search with PRIMA) team acquired simultaneous observations of a bright binary star with PRIMA and the venerable NACO imager. I analyzed the two data sets to place an upper limit on the systematic error in the separation vector inferred from the PRIMA data.

SPHERE

Starlight subtraction for the SPHERE IFS
Presented at a meeting held by the SPHERE Near-Infrared Survey (NIRSUR) data analysis group at IPAG, Grenoble on 12 Dec 2012
During the sub-system testing phase of SPHERE, I investigated starlight subtraction using laboratory data acquired by the integral field spectrograph team (see Zurlo et al. 2014 and Mesa et al. 2014). I demonstrated how a principal component analysis-based algorithm could be applied to the IFS data cubes.