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arXiv · 2504.04930

Ultraviolet Photometry and Reddening Estimation of 105 Galactic Open Clusters

Tahereh Ramezani·Ernst Paunzen·Artem Gorodilov·Olga Ines Pintado
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Abstract

This paper focuses on observing unstudied Galactic open clusters in the Ultraviolet (UV) wavelength range and analyzing their photometric data. The Gaia Data Release 3 (DR3) enables us to precisely study known Galactic open clusters. We conducted observations using the 1.54-meter Danish Telescope (DK1.54) in Chile and the 2.15-meter telescope at the Complejo Astronomico El Leoncito (CASLEO) in Argentina, employing UV filters. Furthermore, we have collected available photometric and astrometric data for our observed clusters. We aim to estimate the reddening of Galactic open clusters using UV photometry. We applied isochrone fitting to determine the reddening of the clusters using well-known members. As a final result, we present the reddening values of 105 Galactic open clusters in the UV, as determined by our photometry.

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Tahereh Ramezani, Ernst Paunzen, Artem Gorodilov, Olga Ines Pintado. 2025-04-07. Ultraviolet Photometry and Reddening Estimation of 105 Galactic Open Clusters. https://arxiv.org/abs/2504.04930

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