Simulations of low surface brightness galaxy emission recovery from LSST

Student: Brandon Kelly
Supervisor: Chris Collins

Credit:LSST  Corporation, Bryn Feldman

The Large Synoptic Survey Telescope (LSST) is a 6.5 m effective diameter survey telescope with a 9.6 square degree field of view, due to carry out a ten-year photometric survey of the southern sky from 2022, with commissioning beginning in 2019. The LSST science pipelines will implement the core image processing and analysis algorithms necessary to process the data. At present, processing codes are being developed to recover the best galaxy morphological parameters for lensing studies. The student will develop models for recovering low surface brightness (LSB) stellar emission from galaxy clusters (intracluster light, ICL) on scales of 50...300 kiloparsecs, reaching to ~0.5 degrees or more. This involves, the initial characterisation of the ICL profile from existing Very Large Telescope observations of rich clusters over a wide redshift  range, combined with simulations using the LSST Photon Simulator package including the effects of the telescope’s Point Spread Function, night sky background and scattered light on the profile measurements; the development of the LSST GalSim open source code to extend the galaxy Sersic profile morphologies to include flatter LSB profiles; the implementation of optimised data reduction methods into Level 2 LSST data products and analysis of the first ICL results from the commissioning of the camera, which start in 2019.