Systematics of toroidal dipole modes in Ca, Ni, Zr, and Sn isotopes
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10405240" target="_blank" >RIV/00216208:11320/19:10405240 - isvavai.cz</a>
Výsledek na webu
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=69Dp8kzrUp" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=69Dp8kzrUp</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1140/epja/i2019-12770-x" target="_blank" >10.1140/epja/i2019-12770-x</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Systematics of toroidal dipole modes in Ca, Ni, Zr, and Sn isotopes
Popis výsledku v původním jazyce
We analyze the relation between isoscalar toroidal modes and so-called pygmy dipole resonance (PDR), which both appear in the same region of low-energy dipole excitations. To this end, we use a theoretical description within the fully self-consistent Skyrme quasiparticle random-phase approximation (QRPA). Test cases are spherical nuclei Ca-40,Ca- 48, Ni-58,Ni- 72, Zr-90,Zr- 100, and Sn-100,Sn- 120,Sn- 132 which cover four different elements and for each element at least two isotopes with different neutron excess, one small and another large. The structure of the modes is investigated in terms of strength functions, transition densities (TD) and transition currents (TC). For all considered nuclei, we see that, independently on whether PDR strength exists or not, the flow pattern in the lower part of the "PDR energy region" is basically an isoscalar vortical toroidal motion with a minor irrotational fraction. A one-to-one correspondence between calculated TD and TC is established. The toroidal flow appears already in the uncoupled two-quasiparticle (2qp) excitations and becomes definitively strong for the QRPA modes. Altogether, we find that low-lying dipole strength often denoted as isoscalar PDR is actually an oversimplified imitation of the basically toroidal motion in nuclei with sufficient neutron excess.
Název v anglickém jazyce
Systematics of toroidal dipole modes in Ca, Ni, Zr, and Sn isotopes
Popis výsledku anglicky
We analyze the relation between isoscalar toroidal modes and so-called pygmy dipole resonance (PDR), which both appear in the same region of low-energy dipole excitations. To this end, we use a theoretical description within the fully self-consistent Skyrme quasiparticle random-phase approximation (QRPA). Test cases are spherical nuclei Ca-40,Ca- 48, Ni-58,Ni- 72, Zr-90,Zr- 100, and Sn-100,Sn- 120,Sn- 132 which cover four different elements and for each element at least two isotopes with different neutron excess, one small and another large. The structure of the modes is investigated in terms of strength functions, transition densities (TD) and transition currents (TC). For all considered nuclei, we see that, independently on whether PDR strength exists or not, the flow pattern in the lower part of the "PDR energy region" is basically an isoscalar vortical toroidal motion with a minor irrotational fraction. A one-to-one correspondence between calculated TD and TC is established. The toroidal flow appears already in the uncoupled two-quasiparticle (2qp) excitations and becomes definitively strong for the QRPA modes. Altogether, we find that low-lying dipole strength often denoted as isoscalar PDR is actually an oversimplified imitation of the basically toroidal motion in nuclei with sufficient neutron excess.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10304 - Nuclear physics
Návaznosti výsledku
Projekt
<a href="/cs/project/GA19-14048S" target="_blank" >GA19-14048S: Zkoumání nových vlastností jaderných elektromagnetických excitací</a><br>
Návaznosti
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Ostatní
Rok uplatnění
2019
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
European Physical Journal A
ISSN
1434-6001
e-ISSN
—
Svazek periodika
55
Číslo periodika v rámci svazku
12
Stát vydavatele periodika
DE - Spolková republika Německo
Počet stran výsledku
15
Strana od-do
242
Kód UT WoS článku
000502144600011
EID výsledku v databázi Scopus
2-s2.0-85076199275