Forward modelling techniques for spectra retrieval of circumstellar debris disks
Abstract
The Gemini Large and Long Program studying circumstellar disks using the Gemini Planet Imager (GPI) is aiming at better constraining the properties of the circumstellar dust, specifically, measuring the near-infrared total intensity and polarization fraction colors, and searching for solid-state spectral features of nearby beta Pic-like disks. This program as already observed 16 disks in one or several of the bandwidths allowed by this instruments. These observations will allow us to break the degeneracy among the particle properties such as composition, size, porosity, and shape. An important step towards this achievement would be to be able to retrieve accurate spectra of the observed debris disks in all the bands of the Integral Field Spectrograph (IFS). Several differential imaging techniques (ADI, SDI) have been developed to improve a posteriori the contrast of the images taken using an IFS. These aggressive techniques, although necessary to detect point-like or extended objects, have important effects on the shape of these objects and their photometry. We present here the forward-modelling technique we developed to remove these effects and obtain accurate spectra of the extended objects in the IFS data. Finally, we present the first results of this technique using the data of the LLP disk program.
- Publication:
-
American Astronomical Society Meeting Abstracts #231
- Pub Date:
- January 2018
- Bibcode:
- 2018AAS...23122903M