"Impact of exceptional point threads on nuclear observables"
Jacek Okołowicz, IFJ PAN
(id #43)
Seminar: YesPoster: No
Invited talk: No
Authors:
Jacek Okołowicz, IFJ PAN
Marek Płoszajczak, GANIL, Caen, France
Recently exceptional points (EP) have been observed in several open resonance cavity experiments. In nuclear physics we do not have a tuning parameter to approach the EP at our disposal. Therefore, we cannot approach it arbitrarily close, but some conclusions can be drawn already if we are in its vicinity. As the EPs are generic for any parameter dependent Hamiltonian, we should be able to find conducive conditions in some exotic nuclei.
We shall discuss different behaviour of some nuclear observables when the EP is being approached. Namely the conduct of a given observable depends on whether related operator commutes with the nuclear Hamiltonian. Apparently non-commuting observables exhibit a singularity at the EP and, consequently, loose their physical meaning. On the other hand those commuting observables, even though regular, can provide some hints of the EP closeness.
We shall present for some model loosely bound (unbound) nucleus 16Ne the impact of EP on nuclear cross section and phase shifts, including unusual 2\pi change of the latter. The idea of EP threads in connection of scattering continuum and their influence on near threshold behaviour of many body states mixing and eigenvectors rigidity will be discussed in detail.
Jacek Okołowicz, IFJ PAN
Marek Płoszajczak, GANIL, Caen, France
Recently exceptional points (EP) have been observed in several open resonance cavity experiments. In nuclear physics we do not have a tuning parameter to approach the EP at our disposal. Therefore, we cannot approach it arbitrarily close, but some conclusions can be drawn already if we are in its vicinity. As the EPs are generic for any parameter dependent Hamiltonian, we should be able to find conducive conditions in some exotic nuclei.
We shall discuss different behaviour of some nuclear observables when the EP is being approached. Namely the conduct of a given observable depends on whether related operator commutes with the nuclear Hamiltonian. Apparently non-commuting observables exhibit a singularity at the EP and, consequently, loose their physical meaning. On the other hand those commuting observables, even though regular, can provide some hints of the EP closeness.
We shall present for some model loosely bound (unbound) nucleus 16Ne the impact of EP on nuclear cross section and phase shifts, including unusual 2\pi change of the latter. The idea of EP threads in connection of scattering continuum and their influence on near threshold behaviour of many body states mixing and eigenvectors rigidity will be discussed in detail.
