High Contrast Observations with Slicer based Integral Field Spectrographs


Graeme Salter, Niranjan Thatte, Matthias Tecza, Fraser Clarke


Oxford Astrophysics


It has previously been thought that non common path errors in image slicer based IFSs would limit the achievable contrast by modifying the speckle pattern, however, recent results have provided reason to doubt this. As part of the EPICS (Exo-Planet Imaging Camera and Spectrograph on the E-ELT) design study an investigation has been made into whether slicer based integral field spectrographs do limit the achievable contrast as opposed to other IFU types.

We have a 2-pronged approach to tackle this question:

1. Simulation - We are simulating the effect of adding in wave front error in the pupil plane on the speckle pattern of a high contrast observation.

2. Experiment - An experimental test bed including a slicer based IFS has been set up for comparison to the simulations and to analyze effects that cannot be well simulated.

Results including speckle rejection factors from experiment and predicted achievable contrasts from simulations will be presented.