Astrometric and photometric calibrators for the 4-m International Liquid Mirror Telescope

Naveen Dukiya; Bhavya Ailawadhi; Talat Akhunov; Ermanno Borra; Monalisa Dubey; Jiuyang Fu; Baldeep Grewal; Paul Hickson; Brajesh Kumar; Kuntal Misra; Vibhore Negi; Kumar Pranshu; Ethen Sun; Jean Surdej

arXiv · 2311.05617

Astrometric and photometric calibrators for the 4-m International Liquid Mirror Telescope

Naveen Dukiya·Bhavya Ailawadhi·Talat Akhunov·Ermanno Borra·Monalisa Dubey·Jiuyang Fu·Baldeep Grewal·Paul Hickson·Brajesh Kumar·Kuntal Misra·Vibhore Negi·Kumar Pranshu·Ethen Sun·Jean Surdej

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Abstract

The International Liquid Mirror Telescope (ILMT) is a 4-meter class survey telescope. It achieved its first light on 29$^{\rm th}$ April 2022 and is now undergoing the commissioning phase. It scans the sky in a fixed \ang{;22;} wide strip centred at the declination of $+$\ang{29;21;41.4} and works in \emph{Time Delay Integration (TDI)} mode. We present a full catalog of sources in the ILMT strip derived by crossmatching \textit{Gaia} DR3 with SDSS DR17 and PanSTARRS-1 (PS1) to supplement the catalog with apparent magnitudes of these sources in $g, r$, and $i$ filters. These sources can serve as astrometric calibrators. The release of Gaia DR3 provides synthetic photometry in popular broadband photometric systems, including the SDSS $g, r$, and $i$ bands for $\sim$220 million sources across the sky. We have used this synthetic photometry to verify our crossmatching performance and, in turn, create a subset of the catalog with accurate photometric measurements from two reliable sources.

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Naveen Dukiya, Bhavya Ailawadhi, Talat Akhunov, Ermanno Borra, Monalisa Dubey, Jiuyang Fu, Baldeep Grewal, Paul Hickson, Brajesh Kumar, Kuntal Misra, Vibhore Negi, Kumar Pranshu, Ethen Sun, Jean Surdej. 2023-11-08. Astrometric and photometric calibrators for the 4-m International Liquid Mirror Telescope. https://arxiv.org/abs/2311.05617

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