1. |
- Elander, Nils, et al.
(författare)
-
Convergence and Quantum Number Assignment Studies of Rovibrational Eigenstates in a Model of Predissociating NeICI van der Waals Complex
- 2009
-
Ingår i: International Journal of Quantum Chemistry. - : Wiley. - 0020-7608 .- 1097-461X. ; 109:3, s. 459-468
-
Tidskriftsartikel (refereegranskat)abstract
- This report details extensions and further analysis of the results presented in an earlier study (Elander et al., Phys Rev A 2001, 64, 012505). Rovibrational resonances in a model of the triatomic van der Waals complex NeICI were studied with a full quantum mechanical, smooth exterior dilation technique realized in a three-dimensional finite element code. Both exact and approximate results, where Coriolis effects are neglected, are presented, and their structures are discussed. Although the helicity is a good quantum number in a one-equation approximation, it is here demonstrated that this is not in the case when including Coriolis coupling, that is, couplings to other helicity components. The behavior of the resonance widths and the positions together with the structure of the resonance wave functions and their dependence on the total angular momentum and its projection have been studied. The dependence of the width of a given resonance oil the total angular momentum was found to be weak while the dependence on the helicity is stronger.
|
|
2. |
- Elander, Nils, et al.
(författare)
-
Quantum Scattering with the Driven Schrödinger Approachand Complex Scaling
- 2009
-
Ingår i: Few-body systems. - Heidelberg : Springer Verlag. - 0177-7963 .- 1432-5411. ; 45:2-4, s. 197-201
-
Tidskriftsartikel (refereegranskat)abstract
- Quantum scattering calculations of two and three-body systems with Coulomb interaction using thedriven Schrödinger equation combined with exterior complex scaling are discussed. A rigorous formulationfor two-body scattering is reported, and its generalization to three-body scattering is considered.
|
|
3. |
|
|
4. |
- Evgeny, Yarevsky
(författare)
-
Bound states and resonances in three-body system
- 1999
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The quantum three-body problem plays an important role in different branches of the modern physics. In the nuclear, atomic and molecular physics there exist a number of systems whose behaviour is naturally described in this framework.Both bound states and scattering processes in three-body systems are of great theoretical and experimental importance.In this thesis an unified approach for a study of three-body systems is suggested.It consists of the total angular momentum representation for the wave function, the exterior complex scaling method and the three-dimensional finite element method.This combination forms a mathematically rigorous and computationally precise and effective approach to treat three-body problems and gives a possibility to calculate various systems from different field of physics.The recently discovered antiprotonic helium system provides an unique example of relatively long co-existence of matter and antimatter. Also, it is one of very few three-body systems where very accurate experimental data are available. It is unusual from theoretical point of view as it possesses very high angular momentum, up to 40, and shares both properties of molecular and atomic systems. In this thesis we present calculation of energy levels, transition wavelengths, and lifetimes for both the 3He and the 4He isotopic species of the antiprotonic helium.The normal helium atom is a good test case for any method as a lot of very accurate experimental and theoretical results are available. Calculations of doubly excited states in helium are presented. The results clearly illustrated the preciseness of the present approach.Another implementation is found in the nuclear physics. It is shown how angular dependent interactions, which are typical for nuclear physics problems, can be incorporated in the formalism. The test case of the halo nucleus 11Li is investigated. In the molecular physics, the weakly bound van der Waals complex NeICl is considered, and its bound states and resonances are computed.
|
|
5. |
- Gagin, Anton, et al.
(författare)
-
Eigen Energies and the Statistical Distributions of the Rovibrational Levels of the Bosonic van der Waals Argon Trimer
- 2009
-
Ingår i: Journal of Physical Chemistry A. - : American Chemical Society (ACS). - 1089-5639 .- 1520-5215. ; 113:52, s. 14979-14986
-
Tidskriftsartikel (refereegranskat)abstract
- The eigen energies and the statistical distributions of the rovibrational levels (J = 0-2) of the bosonic van der Waals argon trimer were calculated using a full angular momentum three-dimensional finite element method. The influence of interatomic potentials on the vibrational levels and statistical properties of the trimer was discussed.
|
|
6. |
- Salci, Moses, et al.
(författare)
-
A theoretical study of the rovibrational levels of the bosonic van der Waals neon trimer
- 2008
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 129:13, s. 134304-
-
Tidskriftsartikel (refereegranskat)abstract
- The eigenenergies and root mean square radii of the rovibrational levels (J=0-3) of the weakly bound bosonic van der Waals neon trimer were calculated using a full angular momentum three-dimensional finite element method. The differing results of three previous studies for zero angular momentum are discussed, explained, and compared with the results presented here.
|
|
7. |
- Salci, Moses, et al.
(författare)
-
Finite element investigation of the ground states of the helium trimers 4He3 and 4He2–3He
- 2007
-
Ingår i: International Journal of Quantum Chemistry. - : Wiley Periodicals. - 0020-7608 .- 1097-461X. ; 107:7, s. 464-468
-
Tidskriftsartikel (refereegranskat)abstract
- A three-dimensional finite element method is applied to the ground states of the symmetric and asymmetric atomic helium trimers 4He3 and 4He2–3He. Three different He–He interaction potentials of hard-core nature were studied. Two extrapolation procedures based on the convergence properties of the finite element method are investigated.
|
|
8. |
|
|
9. |
|
|
10. |
|
|