Mirror symmetry at far edges of stability: The cases of and
S Koyama
(1)
,
D Suzuki
,
M Assié
(2)
,
L Lalanne
(1, 2)
,
O Sorlin
(1)
,
T Abe
,
D Beaumel
(2)
,
Y Blumenfeld
(2)
,
L Caceres
(1)
,
F de Oliveira Santos
(1)
,
F Delaunay
(3)
,
F Flavigny
(2, 3)
,
S Franchoo
(2)
,
J Gibelin
(3)
,
V Girard-Alcindor
(1, 2)
,
J Guillot
(2)
,
F Hammache
(2)
,
O Kamalou
(1)
,
A Kamenyero
(1)
,
N Kitamura
,
V Lapoux
(4)
,
A Lemasson
(1)
,
A Matta
(3)
,
B Mauss
(1)
,
P Morfouace
(5, 1)
,
M Niikura
,
H Otsu
,
J Pancin
(1)
,
T Roger
(1)
,
T.Y Saito
,
H Sakurai
,
C Stodel
(1)
,
J-C Thomas
(1)
D Suzuki
- Fonction : Auteur
T Abe
- Fonction : Auteur
F Delaunay
- Fonction : Auteur
- PersonId : 740010
- IdHAL : franck-l-delaunay
- ORCID : 0000-0002-1703-2434
- IdRef : 089345819
N Kitamura
- Fonction : Auteur
M Niikura
- Fonction : Auteur
H Otsu
- Fonction : Auteur
T.Y Saito
- Fonction : Auteur
H Sakurai
- Fonction : Auteur
Résumé
Missing mass spectroscopy of the unbound nucleus was performed by the one-neutron transfer reaction at 55 MeV/nucleon. Besides the known ground state, two new resonant states were observed, the first at an excitation energy of 3.40(25) MeV with a width of 3.0(5) MeV, the second at 18.6(5) MeV with a width of 3.9(11) MeV. Spin and parity were assigned to the first resonance from the distorted-wave Born approximation analysis of the experimental differential cross section. The excitation energy of the resonance in supports the persistence of the subshell closure at the semimagic number = 6, as is the case for = 6. The mirror energy difference relative to the state in (25) MeV, is compatible with zero. Both states represent resonances in the continuum, unbound by about 1.4 and 6.9 MeV, respectively, above the particle thresholds. A simple theoretical model emphasizes the difference in unboundedness to account for a symmetry in mirror energies. This unique system is expected to provide a salient test of theoretical models, which include the treatment of the continuum.