Resolving spectral information of debris disks with angular differential imaging biases
Trisha Bhowmik, Anthony Boccaletti- LESIA, Observatoire de Paris

High contrast imaging of debris disks is an efficient technique to study morphologies and spectral characteristics, in order 
to derive dust grains properties and to ultimately understand the planet-disk interactions. SPHERE is designed with an 
‘Integral Field Spectrograph’ (IFS) and ‘Infrared Dual Imager and Spectrograph’ (IRDIS) working at near-infrared 
wavelengths. These instruments have the ability to observe disks at high spatial, yet low spectral resolution. We have 
initiated a program to locally determine the spectral characteristics of debris disks with the aim to distinguish dust clumps 
from planet formation sites. Given that young debris disks are faint compared to their host stars, their detection relies 
mostly on post-processing techniques like angular differential imaging (ADI), which, in turn, causes bias in the intensity 
map of the disk structure. Different types of models have been developed as tools to mitigate this issue and retrieve 
the spectral information of disk features like rings or clumps. Our procedure involves generating a model grid using 
GraTer modeling, processing it through an ADI algorithm, and fitting the result on data, channel per channel, to build either 
a partial or the complete disk spectrum. We will present our results obtained on debris disks observed with SPHERE.