Database of the Sun observations in the He I 10830 angstroms line obtained with the STT-2 telescope at the Crimean Astrophysical Observatory (CrAO)

ESDB10029 2025120217550000 Ernest Kedrov crossref@gcras.ru World Data Center for Solar-Terrestrial Physics, Geophysical Center of the Russian Academy of Sciences Geophysical Center RAS, Moscow, Russia Olga Andreeva Crimean Astrophysical Observatory of the Russian Academy of Sciences Andrei Plotnikov Crimean Astrophysical Observatory of the Russian Academy of Sciences Valentina Malashchuk Crimean Astrophysical Observatory of the Russian Academy of Sciences Database of the Sun observations in the He I 10830 angstroms line obtained with the STT-2 telescope at the Crimean Astrophysical Observatory (CrAO) Currently, experimental data on solar activity are widely used in fundamental and applied scientific research - the study of phenomena occurring on the Sun and their impact on Earth. The most valuable data are those obtained from long-term observations. The Crimean Astrophysical Observatory of the Russian Academy of Sciences (CrAO) has accumulated unique observational material in the He I 10830 angstroms line on the Solar Tower Telescope-2 (STT-2), allowing the evolution of coronal holes, filaments, and active regions to be analyzed over more than two solar cycles (1999-2025). The authors, preserving the existing unique observational data in the He I 10830 angstroms line obtained on the STT-2 telescope of the CrAO for the specified period, regularly supplementing them with new results and unifying their visualization, have formed a database that provides easy and convenient access to them. FITS files are provided for more complete use. The unified database can be useful to a wide range of researchers in solving scientific problems in the field of studying the nature and evolution of coronal holes, their relationship with other structures on the Sun, as well as studying the nature of the formation of solar wind flows.The DataBase is presented on the websites of the CrAO (https://sun.crao.ru/observations/hel-1083nm) and the World Data Center for Solar-Terrestrial Physics, Moscow (http://www.wdcb.ru/stp/solar/solar_telescope.html). The data are freely accessible. 2025 10 16 2025 Geophysical Center of the Russian Academy of Sciences Moscow, Russia World Data Center for Solar-Terrestrial Physics Moscow, Russia 10.2205/ESDB-SAD-CrAO 2025120217550000 https://esdb.wdcb.ru/doi/2025/esdb-sad-crao.html