The PLACID active coronagraphic imager instrument: commissioning status
Abstract
The world's first adaptive stellar coronagraph, the Programmable Liquid-crystal Active Coronagraphic Imager for the 4-m DAG telescope (PLACID) uses a spatial light modulator operating from H- to Ks-band to dynamically adjust the focal-plane phase mask entirely in software. Positioned between the TROIA XAO system and the DIRAC infrared detector, PLACID was installed on the Nasmyth platform of the Turkish 4-m DAG telescope in 2025, followed by optical alignment and successful preliminary acceptance tests with the calibration light source in early 2026. On-sky commissioning is expected, as soon as the TROIA XAO system will be operational. When on-sky, it will enable high-contrast imaging of exoplanets, brown dwarfs, disks, and binary systems, being able to easily deploy any desired phase pattern in the focal plane. Upcoming features include self-calibration of non-common path aberrations, coronagraphic nulling of binary-stars, and coherent differential imaging. We present the preliminary acceptance procedures and internal alignment results, discovery-space estimates, new binary star features and observation tools, to be ready for first science by late 2026/early 2027.
Versions
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BibTeX
@misc{tandon2026placid,
title = {{The PLACID active coronagraphic imager instrument: commissioning status}},
author = {Ruben Tandon and Lucas Marquis and Liurong Lin and Derya Öztürk Çetni and Axel Potier and Audrey Baur and Iljadin Manurung and Matthias Brändli and Martin Rieder and Daniele Piazza and Laurent Jolissaint and Jonas G. Kühn},
howpublished = {arXiv},
year = {2026},
month = aug,
doi = {10.48550/arxiv.2608.28226},
eprint = {2608.28226},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.28226},
}
RIS
TY - UNPB
TI - The PLACID active coronagraphic imager instrument: commissioning status
AU - Ruben Tandon
AU - Lucas Marquis
AU - Liurong Lin
AU - Derya Öztürk Çetni
AU - Axel Potier
AU - Audrey Baur
AU - Iljadin Manurung
AU - Matthias Brändli
AU - Martin Rieder
AU - Daniele Piazza
AU - Laurent Jolissaint
AU - Jonas G. Kühn
PY - 2026
DA - 2026/08/28
PB - arXiv
DO - 10.48550/arxiv.2608.28226
UR - https://arxiv.org/abs/2608.28226
AB - The world's first adaptive stellar coronagraph, the Programmable Liquid-crystal Active Coronagraphic Imager for the 4-m DAG telescope (PLACID) uses a spatial light modulator operating from H- to Ks-band to dynamically adjust the focal-plane phase mask entirely in software. Positioned between the TROIA XAO system and the DIRAC infrared detector, PLACID was installed on the Nasmyth platform of the Turkish 4-m DAG telescope in 2025, followed by optical alignment and successful preliminary acceptance tests with the calibration light source in early 2026. On-sky commissioning is expected, as soon as the TROIA XAO system will be operational. When on-sky, it will enable high-contrast imaging of exoplanets, brown dwarfs, disks, and binary systems, being able to easily deploy any desired phase pattern in the focal plane. Upcoming features include self-calibration of non-common path aberrations, coronagraphic nulling of binary-stars, and coherent differential imaging. We present the preliminary acceptance procedures and internal alignment results, discovery-space estimates, new binary star features and observation tools, to be ready for first science by late 2026/early 2027.
ER -