Authors

James Hagan, Adrien Thormann, Rémi Soummer, Laurent Pueyo, Christian Marois

Affiliations

STScI

Abstract

In 1998, the star HR8799 was observed using the coronographic camera NIC2 in a survey to search for massive Jupiters around young, nearby, main sequence stars. In 2009, more than a decade later, Lafrenière et al. revisited this data. Along with some prior knowledge of the HR8799 exoplanetary system, they developed and utilized an advanced algorithm for PSF subtraction called the LOCI (locally optimized combination of images) algorithm and detected the exoplanet HR8799 b. We revisit the same data and systematically optimize LOCI parameters. We present the direct detections of HR8799 b, c, and a possible detection of d in the same NICMOS data, and we study the effects the LOCI parameters have on the measured astrometry and photometry of each planet.