IDEN2 - A program for visual identification of spectral lines and energy levels in optical spectra of atoms and simple molecules
Abstract The article describes a Java program that can be used in a user-friendly way to visually identify spectral lines observed in complex spectra with theoretically predicted transitions between atomic or molecular energy levels. The program arranges various information about spectral lines and energy levels in such a way that line identification and determination of positions of experimentally observed energy levels become much easier tasks that can be solved fast and efficiently. Program summary Program title: IDEN2 Program Files doi: http://dx.doi.org/10.17632/mwr2tk84sw.1 Licensing provisions: GPLv3 Programming language: Java v.1.8 Nature of problem: Line identification problem in atomic and molecular spectra that have a limited number of previously known low-excited energy levels and a large number of unidentified spectral lines (emission or absorption). The line identification consists of finding the lower and upper energy levels of transitions corresponding to each observed spectral line. Solution method: For each energy level (experimentally known or unknown), the list of observed spectral lines is displayed on a wavenumber scale as an image. This image is repeated with certain vertical shifts in several columns corresponding to other levels connected with the investigated one by theoretically predicted transitions. In each such column, the image of the line spectrum is shifted by the value corresponding to the energy of the connecting level. Then the problem of location of an unknown level is reduced to scrolling the screen until several spectral lines in different columns align along the same horizontal line. Various gadgets provide complete information about all pertinent entities, such as the level identities, wavelengths, observed and calculated intensities. Additional comments including restrictions and unusual features: A practical limitation on the size of the problem is imposed by the available RAM, which is typically sufficient to treat spectra with up to 100 000 spectral lines and 10 000 energy levels. The visual appearance of all gadgets, including font sizes, colors, and window sizes and positions, is completely customizable. An extensive Help system and User Guide are included.
Analysis of the free ion spectrum of Er3+(Er IV)
The vacuum spark spectrum of erbium is observed in the wavelength region 705–2460 Å where transitions between the low-lying configurations 4 f 11 , 4 f 10 5 d , 4 f 10 6 s and 4 f 10 6 p take place. Predictions of energy levels and electric dipole transition probabilities by means of the Cowan codes served for a complete revised analysis of the spectrum. The identification of 591 spectral lines as transitions mostly between low levels of these four configurations led to the determination of 120 energy levels. Radial parameters obtained in least-squares fits of both parities are compared with ab initio Hartree–Fock integrals including relativistic corrections. The mean error of the fits are respectively 41 cm−1 for 38 known levels of the odd parity configurations 4 f 11 + 4 f 10 6 p and 49 cm−1 for 82 known levels of the even configurations 4 f 10 5 d + 4 f 10 6 s .
A numerical study on liquid ring motion and fragmentation for the initial process of liquid explosive dispersal
For the explosive dispersal on liquid fuel of FAE technique, the expansion of gaseous detonation products, axisymmetric radial extension and fragmentation of a liquid ring were analyzed, then corresponding models were established. By those models coupled, the numerical simulation on motion and fragmentation of the liquid ring exerted by strong action was carried out. The results computed show that the models established are feasible, and present study can offer initial conditions for the numerical simulation on the process of liquid secondary breakup and gas-liquid mixing.