Nuclear structure in the neutron-deficient Sn nuclei TKEL effects on lifetime measurements

The presence of seniority-like isomers along the Z = 50 isotopic chain have been an experimental limitation to the investigation of the electromagnetic properties of the low-lying states in the light Sn nuclei. Combining a multi-nucleon transfer reaction with the Recoil-Distance Doppler-Shift technique, the lifetimes of the 21+ and 41+ excited states have been directly measured in the neutron-deficient 106, 108Sn isotopes for the very first time. The emitted γ rays were detected by the AGATA array, while the reactionproducts were uniquely identified by the VAMOS++ magnetic spectrometer. The control of the direct feeding of the statesby gating on the Total Kinetic Energy Loss, together with the unique capabilities of the two spectrometers, was crucial for the measurementin 108Sn.

Download Full-text

Lifetime measurements in 105Sn: the puzzle of B(E2) strengths in Sn isotopes

EPJ Web of Conferences ◽

10.1051/epjconf/201922301048 ◽

2019 ◽

Vol 223 ◽

pp. 01048

Author(s):

Giorgia Pasqualato ◽

Andrea Gottardo ◽

Alain Goasduff ◽

Josè Javier Valiente Dobón ◽

Daniele Mengoni

Keyword(s):

Excited States ◽

Experimental Technique ◽

Systematic Study ◽

Doppler Shift ◽

Isotopic Chain ◽

Lifetime Measurements ◽

Preliminary Results ◽

Shell Closures ◽

Recoil Distance ◽

Good Agreement

One of the most studied case to explore the evolution of shell closures far from stability is the doubly-magic and self-conjugated 100Sn nucleus. Information on its doubly-magic nature can be extracted fromthe systematic study of the tin isotopic chain. In this context, the lifetimes of the neutron deficient 105Sn have been investigated with the coincidence Recoil Distance Doppler Shift (RDDS) technique throughthe reaction 50Cr(58Ni,2pn)105Sn. Preliminary results concerning the lifetimesof 105In excited states are in good agreement with the adopted lifetimes, demonstrating the feasibility to extract lifetimes with this experimental technique.

Download Full-text

Developing the Recoil Distance Doppler-Shift technique towards a versatile tool for lifetime measurements of excited nuclear states

Progress in Particle and Nuclear Physics ◽

10.1016/j.ppnp.2012.03.003 ◽

2012 ◽

Vol 67 (3) ◽

pp. 786-839 ◽

Cited By ~ 129

Author(s):

A. Dewald ◽

O. Möller ◽

P. Petkov

Keyword(s):

Doppler Shift ◽

Lifetime Measurements ◽

Versatile Tool ◽

Recoil Distance ◽

Shift Technique

Download Full-text

Symmetries in mirror nuclei 31S and 31P

EPJ Web of Conferences ◽

10.1051/epjconf/201819403001 ◽

2018 ◽

Vol 194 ◽

pp. 03001

Author(s):

D. Tonev ◽

G. de Angelis ◽

N. Goutev ◽

S. Iliev ◽

R. Orlandi ◽

...

Keyword(s):

Charged Particle ◽

Excited States ◽

Doppler Shift ◽

Isospin Symmetry ◽

Particle Detector ◽

Lifetime Measurements ◽

Angular Correlations ◽

Doppler Shift Attenuation ◽

First Time

Excited states in mirror nuclei 31S and 31P were populated in the 1n and 1p exit channels, respectively, of the reaction 20Ne + 12C. The beam of 20Ne, with an energy of 33 MeV, was delivered for the first time by the Piave-Alpi accelerator of the Laboratori Nazionali di Legnaro. Angular correlations of coincident pairs and Doppler-shift attenuation lifetime measurements in 31S and 31P were performed using the multidetector array GASP in conjunction with the EUCLIDES charged particle detector. A comparison of the determined B(E1) strengths of the analog mirror 7/2- → 5/2+ transitions indicates the presence of a violation of isospin symmetry.

Download Full-text

Lifetime measurements of excited states in neutron-richAr44,46populated via a multinucleon transfer reaction

Physical Review C ◽

10.1103/physrevc.82.024308 ◽

2010 ◽

Vol 82 (2) ◽

Cited By ~ 40

Author(s):

D. Mengoni ◽

J. J. Valiente-Dobón ◽

A. Gadea ◽

S. Lunardi ◽

S. M. Lenzi ◽

...

Keyword(s):

Excited States ◽

Transfer Reaction ◽

Lifetime Measurements ◽

Multinucleon Transfer Reaction

Download Full-text

LIFETIME MEASUREMENTS OF EXCITED STATES IN 73As

International Journal of Modern Physics E ◽

10.1142/s0218301304002569 ◽

2004 ◽

Vol 13 (05) ◽

pp. 1019-1034 ◽

Cited By ~ 2

Author(s):

K. P. SINGH ◽

T. KAKAVAND ◽

M. HAJIVALIEI

Keyword(s):

Statistical Theory ◽

Excited States ◽

Doppler Shift ◽

Nuclear Reactions ◽

Angular Distributions ◽

Excitation Energies ◽

Lifetime Measurements ◽

Mixing Ratios ◽

Doppler Shift Attenuation ◽

First Time

The excited states of 73 As have been investigated via the 73 Ge ( p , n γ)73 As reaction with proton beam energies from 2.5–4.3 MeV. The lifetimes of the levels at 769.6, 860.5, 1177.8, 1188.7, 1274.9, 1344.1, 1557.1 and 1975.2 keV excitation energies have been measured for the first time using the Doppler shift attenuation method. The angular distributions have been used to assign the spins and the multipole mixing ratios using statistical theory for compound nuclear reactions. The ambiguity in the spin values for the various levels has been removed. The multipole mixing ratios for eight γ-transitions have been newly measured.

Download Full-text

Preliminary results of lifetime measurements in neutron-rich 53Ti

EPJ Web of Conferences ◽

10.1051/epjconf/201922301022 ◽

2019 ◽

Vol 223 ◽

pp. 01022

Author(s):

Alina Goldkuhle ◽

Christoph Fransen ◽

Alfred Dewald ◽

Navin Alahari ◽

Marcel Beckers ◽

...

Keyword(s):

Transfer Reaction ◽

Decay Curve ◽

Yrast Band ◽

Curve Method ◽

Variable Mode ◽

Multinucleon Transfer Reaction ◽

Recoil Distance ◽

Large Acceptance ◽

Deep Inelastic Reactions ◽

First Time

To study the nuclear structure of neutron-rich titanium isotopes, a lifetime measurement was performed at the Grand Accélérateur National d'Ions Lourds (GANIL) facility in Caen, France. The nucleiwere produced in a multinucleon-transfer reaction by using a 6.76 MeV/u 238U beam. The Advanced Gamma Tracking Array (AGATA) was employed for the γ-ray detection and target-like recoils were identified event-by-event by the large-acceptance variable mode spectrometer (VAMOS++). Preliminary level lifetimes of the (5/2−) to 13/2− states of the yrast band in the neutron-rich nucleus 53Ti were measured for the first time employing the recoil distance Doppler-shift (RDDS) method and the compact plunger for deep inelastic reactions. The differential decay curve method (DDCM) was used to obtain the lifetimes from the RDDS data.

Download Full-text