L. Cáceres
A5065425940- Nuclear physics research studies
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Astronomical and nuclear sciences
- Quantum Chromodynamics and Particle Interactions
- Nuclear reactor physics and engineering
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced NMR Techniques and Applications
- Advanced Chemical Physics Studies
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astro and Planetary Science
- Quantum chaos and dynamical systems
- High-Energy Particle Collisions Research
- Radiopharmaceutical Chemistry and Applications
- Radioactive Decay and Measurement Techniques
- Quantum, superfluid, helium dynamics
- Particle accelerators and beam dynamics
- Boron Compounds in Chemistry
- Cold Fusion and Nuclear Reactions
- Fusion materials and technologies
- Rare-earth and actinide compounds
- Educational Innovations and Technology
- E-Learning and Knowledge Management
- Spectroscopy and Laser Applications
Universidad César Vallejo
2023
Institut National de Physique Nucléaire et de Physique des Particules
2010-2017
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2007-2017
GANIL
2010-2017
Centre National de la Recherche Scientifique
2010-2017
GSI Helmholtz Centre for Heavy Ion Research
2007-2015
Universidad Autónoma de Madrid
2006-2015
Université de Bordeaux
2015
University of Liverpool
2014
RIKEN Nishina Center
2010
The low-lying structure of $^{188,190,192}\mathrm{W}$ has been studied following $\ensuremath{\beta}$ decays the neutron-rich mother nuclei $^{188,190,192}\mathrm{Ta}$ produced projectile fragmentation a 1-GeV-per-nucleon $^{208}\mathrm{Pb}$ primary beam on natural beryllium target at GSI Fragment Separator. $\ensuremath{\beta}$-decay half-lives $^{188}\mathrm{Ta}$, $^{190}\mathrm{Ta}$, and $^{192}\mathrm{Ta}$ have measured, with $\ensuremath{\gamma}$-ray states in their respective W...
Time-resolved Schottky mass spectrometry has been applied to uranium projectile fragments which yielded the value for 208Hg (Z=80, N=128) isotope. The excess of ME=-13 265(31) keV obtained, used determine proton-neutron interaction strength in 210Pb, as a double difference atomic masses. results show dramatic variation lead isotopes when crossing N=126 neutron shell closure, thus confirming empirical predictions that this is sensitive overlap wave functions last valence neutrons and protons.
A β-decaying high-spin isomer in (96)Cd, with a half-life T(1/2)=0.29(-0.10)(+0.11) s, has been established stopped beam rare isotope spectroscopic investigations at GSI (RISING) experiment. The nuclei were produced using the fragmentation of primary (124)Xe on (9)Be target. From and observed γ decays daughter nucleus, (96)Ag, we conclude that state is long predicted 16(+) "spin-gap" isomer. Shell-model calculations, Gross-Frenkel interaction πν(p(1/2),g(9/2)) model space, show isoscalar...
This Letter reports on a systematic study of β-decay half-lives neutron-rich nuclei around doubly magic Pb208. The lifetimes the 126-neutron shell isotone Pt204 and neighboring Ir200–202, Pt203, Au204 are presented together with other 19 measured during "stopped beam" campaign rare isotope investigations at GSI collaboration. results constrain main nuclear theories used in calculations r-process nucleosynthesis. Predictions based statistical macroscopic description first-forbidden β strength...
The ${2}_{1}^{+}$ states of $^{114,116}\mathrm{Sn}$ were excited in two consecutive experiments by means Coulomb excitation inverse kinematics on a $^{58}\mathrm{Ni}$ target. A precise determination the reduced transition probability $B(E2$; ${0}_{\mathrm{g}.\mathrm{s}.}^{+}\ensuremath{\rightarrow}{2}_{1}^{+})$ $^{114}\mathrm{Sn}$ relative to well-known strength $^{116}\mathrm{Sn}$ was achieved comparing projectile target ${2}_{1}^{+}\ensuremath{\rightarrow}{0}_{\mathrm{g}.\mathrm{s}.}^{+}$...
The \ensuremath{\gamma} decays from an isomeric ${10}^{+}$ state at 6457 keV in the nucleus ${}_{28}^{54}$${\mathrm{Ni}}_{26}$ have been identified using GSI fragment separator conjunction with RISING Ge-detector array. is interpreted as isobaric analog of 6527-keV isomer ${}_{26}^{54}$${\mathrm{Fe}}_{28}$. results are discussed terms isospin-dependent shell-model calculations. Clear evidence presented for a discrete $\ensuremath{\ell}=5$ proton decay branch into first excited...
Gamma rays de-exciting isomeric states in the neutron-rich nucleus ${}_{76}^{198}$${\mathrm{Os}}_{122}$ have been observed following relativistic projectile fragmentation of a 1 GeV per nucleon $^{208}\mathrm{Pb}$ beam. The ground-state band has properties compatible with oblate deformation. evolution structure Os isotopes characterized by sudden prolate-oblate shape change is discussed and contrasted smooth known Pt chain.
Neutron-rich silver isotopes were populated in the fragmentation of a ${}^{136}$Xe beam and relativistic fission ${}^{238}$U. The fragments mass analyzed with GSI Fragment Separator subsequently implanted into passive stopper. Isomeric transitions detected by 105 high-purity germanium detectors. Eight isomeric states observed ${}^{122\ensuremath{-}126}$Ag nuclei. level schemes ${}^{122,123,125}$Ag revised extended being for first time. excited odd-mass are interpreted as core-coupled states....
We have studied the β decay of Tz=−1,f7/2 shell nuclei Ni54,Fe50,Cr46, and Ti42 produced in fragmentation reactions. The proton separation energies daughter Tz=0 are relatively large (≈4–5 MeV) so studies γ rays essential. experiments were performed at GSI as part Stopped-beam campaign with RISING setup consisting 15 Euroball Cluster Ge detectors. From newly obtained high precision β-decay half-lives, excitation energies, branching ratios, we able to extract Fermi Gamow-Teller transition...
Long-lived isomers in $^{212}\mathrm{Bi}$ have been studied following $^{238}\mathrm{U}$ projectile fragmentation at 670 MeV per nucleon. The products were injected as highly charged ions into a storage ring, giving access to masses and half-lives. While the excitation energy of first isomer was confirmed, second observed 1478(30) keV, contrast previously accepted value $>1910\text{ }\text{ }\mathrm{keV}$. It also found an extended Lorentz-corrected in-ring half-life $>30\text{...
The neutron-rich N=126 nucleus 205Au has been populated following the relativistic energy projectile fragmentation of E/A=1GeV 208Pb, and studied via charged-particle decay spectroscopy. An internal with a transition 907(5) keV half-life T1/2=6(2)s identified through observation corresponding K L conversion electron lines. 907 level corresponds to πh11/2−1 proton–hole state decays both internally into πd3/2−1 ground-state β 205Hg. obtained data provides information on evolution single-proton...
The $\ensuremath{\beta}$ decay of five heavy, neutron-rich nuclei, ${}^{203,204}$Pt and ${}^{200\ensuremath{-}202}$Ir, has been investigated following relativistic cold fragmentation reactions lead projectiles using the FRS+RISING setup at GSI. This paper reports on study low-lying states in daughter nuclei ${}^{203,204}$Au ${}^{200\ensuremath{-}202}$Pt. characteristic $\ensuremath{\gamma}$ rays for each nucleus have determined $\ensuremath{\beta}$-delayed $\ensuremath{\gamma}$-ray...
The results of a study the $\ensuremath{\beta}$ decays three proton-rich nuclei with ${T}_{z}=\ensuremath{-}2$, namely $^{48}\mathrm{Fe},^{52}\mathrm{Ni}$, and $^{56}\mathrm{Zn}$, produced in an experiment carried out at GANIL, are reported. In all cases we have extracted half-lives total $\ensuremath{\beta}$-delayed proton emission branching ratios. We measured individual protons $\ensuremath{\gamma}$ rays ratios corresponding levels. Decay schemes been determined for nuclei, new energy...
The relativistic projectile fragmentation of a 750 MeV per nucleon beam $^{107}\mathrm{Ag}$ was used to populate isomeric states in neutron-deficient nuclei around $A=80\text{--}90$. Reaction products were separated and unambiguously identified using the GSI FRagment Separator (FRS) its ancillary detectors. At final focal plane, fragments slowed from energies by means an aluminium degrader implanted passive stopper center high-efficiency, high-granularity Stopped Rare Isotope Spectroscopic...
Heavy neutron-rich nuclei were populated via relativistic energy fragmentation of a E / A = 1 GeV 208 Pb beam. The interest selected and identified by fragment separator then implanted in passive plastic stopper. Delayed γ rays following internal isomeric decays detected the RISING array. Experimental information was obtained on number with Z 73-80 ( Ta - Hg ), providing new both prolate-oblate transitional region as well N 126 closed shell nuclei.
The production cross sections of four $N=127$ isotones (${}^{207}$Hg, ${}^{206}$Au, ${}^{205}$Pt, and ${}^{204}$Ir) have been measured using ($p$,$n$) charge-exchange reactions, induced in collisions a ${}^{208}$Pb primary beam at 1 A GeV with Be target. These data allow one to investigate the use reaction mechanism extend limits chart nuclides toward important $r$-process nuclei region third peak elemental abundance distribution.
Excited states in ${}^{96}$Ag were populated fragmentation of an 850-MeV/u ${}^{124}$Xe beam on a 4-g/cm${}^{2}$ Be target. Three new high-spin isomers identified and the structure was investigated. The level scheme established, spin parity (13${}^{\ensuremath{-}}$), (15${}^{+}$), (19${}^{+}$) assigned to isomeric states. Shell-model calculations performed various model spaces, including $\ensuremath{\pi}\ensuremath{\nu}({p}_{1/2},{g}_{9/2},{f}_{5/2},{p}_{3/2})$ large-scale shell-model space...
The low-lying structures of the self-conjugate (N=Z) nuclei 8241Nb41 and 8643Tc43 have been investigated using isomeric-decay spectroscopy following projectile fragmentation a 107Ag beam. These represent heaviest odd–odd N=Z in which internal decays identified to date. resulting level schemes shed light on shape evolution along line between doubly-magic systems 5628Ni 10050Sn support preference for T=1 states Tz=0 at low excitation energies associated with neutron–proton pairing gap....
The spin and configurational structure of excited states $^{127}\mathrm{Cd}$, the two-proton three-neutron hole neighbor $^{132}\mathrm{Sn}$, has been studied. An isomeric state with a half-life 17.5(3) $\ensuremath{\mu}$s was populated in fragmentation $^{136}\mathrm{Xe}$ beam on $^{9}\mathrm{Be}$ target at energy 750 MeV/u. Time distributions delayed $\ensuremath{\gamma}$ transitions $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidence relations were exploited to construct decay scheme....