CASTLE: performances and science cases

TL;DR

CASTLE is a novel telescope concept designed to observe the low surface brightness Universe with high precision, utilizing curved detectors to minimize systematic effects and enable studies of faint cosmic features and transient events.

Contribution

It introduces the CASTLE telescope with a curved detector system, optimized for low surface brightness observations and transient detection, advancing capabilities in faint universe studies.

Findings

Design achieves very low PSF wings and reduced ghost features.

Enables detection of features much fainter than the sky background.

Will significantly improve localization of astrophysical transients.

Abstract

We present here the Calar Alto Schmidt-Lemaitre Telescope (CASTLE) concept, a technology demonstrator for curved detectors, that will be installed at the Calar Alto Observatory (Spain). This telescope has a wide field of view (2.36x1.56 deg^2) and a design, optimised to generate a Point Spread Function with very low level wings and reduced ghost features, which makes it considerably less susceptible to several systematic effects usually affecting similar systems. These characteristics are particularly suited to study the low surface brightness Universe. CASTLE will be able to reach surface brightness orders of magnitude fainter than the sky background level and observe the extremely extended and faint features around galaxies such as tidal features, stellar halos, intra-cluster light, etc. CASTLE will also be used to search and detect astrophysical transients such as gamma ray bursts (GRB), gravitational wave optical counterparts, neutrino counterparts, etc. This will increase the number of precisely localized GRBs from 20% to 60% (in the case of Fermi/GMB GRBs).