DFis-Artículos, capítulos...
http://hdl.handle.net/10396/2290
2019-11-18T08:00:06ZSinglet vs. triplet interelectronic repulsion in confined atoms
http://hdl.handle.net/10396/18642
Singlet vs. triplet interelectronic repulsion in confined atoms
Sarsa, A.; Buendía, E.; Gálvez, F.J.; Katriel, J.
Hund’s multiplicity rule invariably holds for the ground configurations of few-electron atoms as well as those of multi-electron quantum dots. However, the ordering of the corresponding interelectronic repulsions exhibits a reversal in the former but not in the latter system, upon varying the system parameters. Here, we investigate the transition between these two types of behaviour by studying few-electron atoms confined in spherical cavities. “Counter-intuitive” ordering of the interelectronic repulsions is confirmed when the nuclear charge is low enough and the cavity radius is large enough.
Embargado hasta 16/06/2020
2018-01-01T00:00:00ZQuantum defect asymptotics at the critical charge: A study of the integrality conjecture
http://hdl.handle.net/10396/18641
Quantum defect asymptotics at the critical charge: A study of the integrality conjecture
Sarsa, A.; Katriel, J.
A single (n, ℓ) electron outside an (N −1)-electron atomic core is bound as long as Z > Zc = N − 1. A conjecture is examined, according to which the quantum defect of the outermost electron satisfies limZ!Zc δn,ℓ(Z) = Nℓ, where Nℓ is the number of occupied or partially occupied orbitals with angular momentum quantum number ℓ within the (N − 1)-electron core. Specifically, the 3s quantum defect is inspected for the different occupancies of the n = 1 and n = 2 shells. The conjecture is found to hold in all the cases considered.
Embargado hasta 16/08/2020
2018-01-01T00:00:00ZA simple and accurate analytical model of the Stark profile and its application to plasma characterization
http://hdl.handle.net/10396/18555
A simple and accurate analytical model of the Stark profile and its application to plasma characterization
Díaz Soriano, Antonio Manuel; Alcaraz Pelegrina, José Manuel; Sarsa, A.; Dimitrijević, Milan S.; Yubero, Cristina
Optical Emission Spectroscopy techniques are among the most employed to perform the characterization of laboratory plasmas. The analysis of the obtained data is based on the convolution of three different types of profiles: Lorentzians, Gaussians and Starks. While analytic expressions are available for the first two types, the Stark profile has been traditionally obtained through theoretical calculations using different models. In this paper, we propose is a simple and accurate analytical function that can be employed as approximation of a Stark profile. The application of this new model may simplify the analysis of plasmas.
Embargado hasta 01/03/2020
2018-01-01T00:00:00ZSimple and analytical function for the Stark profile of the Hα line and its application to plasma characterization
http://hdl.handle.net/10396/18553
Simple and analytical function for the Stark profile of the Hα line and its application to plasma characterization
Díaz Soriano, Antonio Manuel; Dimitrijević, Milan S.; Alcaraz Pelegrina, José Manuel; Sarsa, A.; Yubero, Cristina
The increasing application of plasma based technologies over a wide range of fields has led to the necessity of an optimal determination of the characteristic parameters of the plasma systems. Optical Emission Spectroscopy techniques have been proved as an excellent tool to that end. These techniques are based on the collection and analysis of the radiation coming from the plasma, being classified between molecular and atomic emission. Among atomic emission lines, Hydrogen Balmer series lines are the most measured. The Hβ line is usually the most employed one for plasma diagnosis but under some conditions, the Hβ line is not always detectable and only the Hα line can be detected. For these lines, it is well known that their shapes are the result of the convolution of three profile types: Lorentzians, Gaussians and Starks. But while the first two types present analytical functions, models explaining the Stark profile do not offer these. So, in this paper we propose an accurate analytical function for the Stark profile of the Hα line allowing improving the determination of characteristic parameters of plasma with respect to the methods traditionally used.
Embargado hasta 01/09/2020
2018-01-01T00:00:00Z