MOL-D: A Collisional Database and Web Service within the Virtual Atomic and Molecular Data Center

Opacities of the solar and stellar atmospheres are caused by a large number of radiative processes. Within development of more sophisticated stellar atmosphere models, we can further investigate known processes and include all processes not considered before. We calculate the average cross-section and rate coefficients for the photodissociation of the alkali molecular ions Li + 2 , Na + 2 and LiNa + ready for further use with a particular accent to the applications for astro plasma research and low temperature laboratory plasma research.

Section: Resultsmentioning

confidence: 99%

Photoionization of the alkali molecular ions in geo-cosmical plasmas

Ignjatović¹,

Srećković²,

Dimitrijević³

2020

“…The database is hosted at the Belgrade Astronomical Observatory, http://servo.aob.rs (Jevremović et al, 2009). The corresponding data are important for exploring the dense molecular clouds in the interstellar medium (ISM), surfaces of small bodies and satellites in our Solar System, modeling of different stellar atmospheres (see the papers Srećković et al 2018;Vujčić et al 2015). Collections of such data sets are as well important for the early Universe chemistry and also for understanding the molecular origins of life (Tielens, 2013;Mason et al, 2014).…”

Section: Moldmentioning

confidence: 99%

Databases for collisional and radiative processes in small molecules needed for spectroscopy use in astrophysics

Jevremović¹,

Srećković²,

Marinković³

et al. 2020

Self Cite

In this contribution we present a report on two atomic/molecular databases for collisional and radiative processes, BEAMDB and MolD, which are web services at the Serbian Virtual Observatory (SerVO) and nodes within the Virtual Atomic and Molecular Data Center (VAMDC). Within the BEAMDB there are mainly electron scattering cross section data, but having in mind the importance of spectroscopic data obtained by particle collisions, we also provide a number of electron energy loss spectra and threshold electron spectra. Electron loss spectroscopy with its complementarity to the photon absorption data, provides valuable information on the optically forbidden atomic and molecular transitions. The MolD database contains photodissociation cross sections for the individual ro-vibrational states of the diatomic molecular ions as well as corresponding data on molecular species and molecular state characterizations. The data can be used for further applications, e.g., for non-local thermal equilibrium modeling of early universe chemistry, modeling of the solar atmosphere, atmospheres of white dwarfs, etc.

“…The aim of this work is to find out at what plasma conditions collisional ionisation/recombination become important and to update values and eliminate uncertainties of the rate coefficients due to hydrogen collisions (Barklem, 2007;Srećković et al, 2018a) in order that they can be properly included in numerical simulations and modelling (Ferland et al, 1998(Ferland et al, , 2017 as well as in the A&M databases (Vujčić et al, 2015;Dubernet et al, 2016;Marinković et al, 2017).…”

Section: The Collisional Ionisation/recombination Datamentioning

confidence: 99%

The influence of collisional-ionization and recombination processes on spectral line shapes in stellar atmospheres and in the hydrogen clouds in broad-line region of AGNs

Srećković¹,

Dimitrijević²,

Ignjatović³

2020

In this paper, the importance of H * (n) + H(1s) collisional ionization as well as the influence of inverse recombination processes in different environments has been investigated within the regions 2 ≤ n ≤ 20 and 4 000 K ≤ T ≤ 20 000 K. The interpretation of this influence is based on existing method of describing inelastic processes in symmetrical atomRydberg-atom collisions. These processes have effect on ionization and the populations of hydrogen excited atoms in moderately ionized plasma layers. From the results it follows that the investigation of these processes is of interest for the research and modelling of such medium.