The Spectr-W database on the spectroscopic properties of atoms and ions.

The Spectr-W database was developed in 2001-2013 and is available online (http://spectrw3. snz.ru). The database contains information on various spectroscopic constants of atoms and ions such as the wavelengths and probabilities of radiative transitions, energy levels of atoms and ions, ionization potentials, autoionization rates, and the parameters of analytical approximation of cross sections and rates of collisional transitions in atoms and ions. Spectr-W presently contains around 450 thousand records and is the world's largest factual database on spectral properties of multicharged ions. A new stage of development of Spectr-W, which involves adding a new section titled 'Emission Spectrograms' to the database, commenced in 2014. In contrast to the already existing sections that contain tabulated data, this new section provides graphical data (with necessary explanatory notes) on the spectrograms of emission of atoms and ions excited in various plasma sources. The structure of sections of the Spectr-W database is characterized, and examples of queries and the corresponding search results are given. [ABSTRACT FROM AUTHOR]