Photometric calibration of the 4m ILMT data
Abstract
The International Liquid Mirror Telescope (ILMT) is a 4-meter survey telescope continuously observing towards the zenith in the SDSS g', r', and i' bands. This survey telescope is designed to detect various astrophysical transients (for example, supernovae) and very faint objects like multiply-imaged quasars and low surface brightness galaxies. Ensuring accurate and stable calibration of supernova (SN) and quasar measurements is essential for studying their intrinsic variability and long-term brightness evolution. In this work, we present a dedicated calibration approach tailored for ILMT point-like object observations obtained in Time Delayed Integration (TDI) mode. Using ZTF reference sources cross-matched with the Pan-STARRS1 catalog, we derive robust photometric zero-points along the ILMT scan. This calibration procedure enables the production of consistent, high-precision SN and quasar light curves, suitable for variability studies, structure-function analysis, and future reverberation-mapping applications.
Related
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- Optical observations of supernova candidates with the ILMT
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BibTeX
@misc{ailawadhi2026photometric,
title = {{Photometric calibration of the 4m ILMT data}},
author = {Bhavya Ailawadhi and Talat Akhunov and Monalisa Dubey and Naveen Dukiya and Sara Filali and Paul Hickson and Priyanshi Kumari and Gokul Singh Mehra and Kuntal Misra and Vibhore Negi and Kumar Pranshu and Jean Surdej and Sarvesh Kumar Yadav},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.04445},
eprint = {2611.04445},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.04445},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Photometric calibration of the 4m ILMT data
AU - Bhavya Ailawadhi
AU - Talat Akhunov
AU - Monalisa Dubey
AU - Naveen Dukiya
AU - Sara Filali
AU - Paul Hickson
AU - Priyanshi Kumari
AU - Gokul Singh Mehra
AU - Kuntal Misra
AU - Vibhore Negi
AU - Kumar Pranshu
AU - Jean Surdej
AU - Sarvesh Kumar Yadav
PY - 2026
DA - 2026/11/03
PB - arXiv
DO - 10.48550/arxiv.2611.04445
UR - https://arxiv.org/abs/2611.04445
AB - The International Liquid Mirror Telescope (ILMT) is a 4-meter survey telescope continuously observing towards the zenith in the SDSS g', r', and i' bands. This survey telescope is designed to detect various astrophysical transients (for example, supernovae) and very faint objects like multiply-imaged quasars and low surface brightness galaxies. Ensuring accurate and stable calibration of supernova (SN) and quasar measurements is essential for studying their intrinsic variability and long-term brightness evolution. In this work, we present a dedicated calibration approach tailored for ILMT point-like object observations obtained in Time Delayed Integration (TDI) mode. Using ZTF reference sources cross-matched with the Pan-STARRS1 catalog, we derive robust photometric zero-points along the ILMT scan. This calibration procedure enables the production of consistent, high-precision SN and quasar light curves, suitable for variability studies, structure-function analysis, and future reverberation-mapping applications.
ER -