The Programmable Liquid-crystal Active Coronagraphic Imager for the DAG telescope (PLACID) instrument is a novel high-contrast direct imaging facility that will come online on the Turkish 4-m DAG telescope later this year. In a nutshell, PLACID will consist in a fore-optics coronagraphic intermediate stage platform, located downstream the TROIA XAO system and upstream of the DIRAC HAWAII-2RG focal-plane array. The PLACID project, led by a consortium of Swiss Universities contracted by the Atatürk University Astrophysics Research and Application Center (ATASAM), passed Factory Acceptance Review in May 2023 and was delivered to site (Karakaya Ridge, 3,200m ASL, Erzurum, Turkey) in March 2024. The commissioning and first light are currently scheduled for the end of 2024. In practice, PLACID will be the world’s first ever “active coronagraph” facility, fielding a customized spatial light modulator (SLM) acting as a dynamically programmable focal-plane phase mask (FPM) coronagraph from H- to Ks-band. This will provide a wealth of novel options to the observers, among which software-only abilities to change or re-align the coronagraphic FPM pattern in function of conditions or science requirements, free of any actuator motion. Future capabilities will include non-common path aberrations (NCPA) self-calibration, optimized coronagrphy for binaries or multiple stars, as well as coherent differential imaging (CDI). As such, the PLACID facility will be a platform of choice for international collaborations and prototyping of new concepts, with anticipated very positive impact for the nascent Turkish astronomy community.
