Search results for "Excitation function"

Excitation Functions of 14N(d,t)13N and 14N(d,αn)11C Reactions from Threshold to 12.3 MeV : Radionuclidic Purity of 150 Produced via the 14N(d,n)15O …

1998

Resonances in the electron impact excitation of metastable states of mercury

1984

Metastable excitation of mercury by electron impact is studied at energies up to the first ionisation potential using an energy selected electron beam with an energy spread of 50 meV FWHM. A great number of resonances is observed in the excitation function. Agreement is good on the whole with a recent relativisticR-matrix calculation and with a former analysis of resonances in the elastic cross section.

Study of a-cluster states of 22Mg from resonance scattering of a post-accelerated 18Ne radioactive ion beam

2002

An experiment aimed at the study of the α-cluster structure of 22Mg was performed at the Louvain la Neuve RIB facility. Preliminary results from a first feasibility run will be presented.

Multiphonon couplings in the sub-barrier fusion of 36S+140Ce

2006

Fusion cross sections have been measured for the system 36S + 140Ce in the energy range encompassing the Coulomb barrier. A representation of the fusion barrier distribution has been obtained from the second energy derivative of the excitation function. The data are well described by coupled‐channels calculations including two‐phonon states of quadrupole and octupole character in the target (140Ce) and one octupole phonon in the projectile. The importance of 140Ce low‐lying inelastic excitations has been pointed out.

T=5/2states in9Li:Isobaric analog states of9He

2003

The thick target inverse kinematic method was applied to the study of isobaric analog states in the neutron-rich nucleus ${}^{9}\mathrm{Li}.$ For this purpose, an excitation function for ${}^{8}\mathrm{He}+p$ elastic scattering was measured in the center-of-momentum energy range from 1.6 to 5.8 MeV. Three $T=5/2$ states in ${}^{9}\mathrm{Li}$ (isobaric analogs of ${}^{9}\mathrm{He})$ were observed. Restrictions on the spin-parity assignments are provided according to R-matrix calculations, and conclusions regarding the structure of ${}^{9}\mathrm{He}$ are given.

Observation of the3nEvaporation Channel in the Complete Hot-Fusion ReactionMg26+Cm248Leading to the New Superheavy NuclideHs271

2008

The analysis of a large body of heavy ion fusion reaction data with medium-heavy projectiles ($6\ensuremath{\le}Z\ensuremath{\le}18$) and actinide targets suggests a disappearance of the $3n$ exit channel with increasing atomic number of the projectile. Here, we report a measurement of the excitation function of the reaction $^{248}\mathrm{Cm}(^{26}\mathrm{Mg},xn)^{274\mathrm{\text{\ensuremath{-}}}x}\mathrm{Hs}$ and the observation of the new nuclide $^{271}\mathrm{Hs}$ produced in the $3n$ evaporation channel at a beam energy well below the Bass fusion barrier with a cross section comparable to the maxima of the $4n$ and $5n$ channels. This indicates the possible discovery of new neutron-r…

Experimental study of the quasifission, fusion-fission, and de-excitation of Cf compound nuclei

2015

Background: The fusion-evaporation reaction at energies around the Coulomb barrier is presently the only way to produce the heaviest elements. However, formation of evaporation residues is strongly hindered due to the competing fusion-fission and quasifission processes. Presently, a full understanding of these processes and their relationships has not been reached.Purpose: This work aims to use new fission measurements and existing evaporation residue and fission excitation function data for reactions forming Cf isotopes to investigate the dependence of the quasifission probability and characteristics on the identities of the two colliding nuclei in heavy element formation reactions.Method:…

Decay properties of neutron-deficient isotopes 256, 257Db, 255Rf, 252, 253Lr

2001

Isotopes of dubnium (element 105) with mass numbers A = 256, 257, and 258 were produced by the reaction 209Bi(50Ti,xn) 259-xDb (x = 1, 2, 3) at projectile energies of (4.59-5.08) AMeV. Excitation functions were measured for the 1n, 2n and 3n evaporation channels. The same position of the excitation function was observed for the 1n channel as for the previously measured 1n channel of the reaction 208Pb(50Ti,1n)257Rf. The measured α-decay data of 257Db and its daughter products resulted in the identification of α-decaying isomeric states in 257Db and 253Lr. Two new isotopes, 256Db and 252Lr, were produced at the highest bombarding energies of 4.97 AMeV and 5.08 AMeV. They were identified by d…

2p-shell admixtures in pion single charge exchange on 13C

1991

Abstract The pion charge exchange process 13 C (π + , π 0 ) 13 N(gs) is calculated with an extended nuclear wave function for the A=13 system that includes configurations outside the 1p-shell. A small amount of 2p-shell admixtures leads to an improved description of the experimental excitation function. We also find a strong sensitivity of the differential cross sections as well as asymmetry to contributions from higher shells.

Molecular structures inT=1states of10B

2011

Multi-center (molecular) structures can play an important role in light nuclei. The highly deformed rotational band in 10Be with band head at 6.179 MeV has been observed recently and suggested to have an exotic alpha:2n:alpha configuration. A search for states with alpha:pn:alpha two-center molecular configurations in 10B that are analogous to the states with alpha:2n:alpha structure in 10Be has been performed. The T=1 isobaric analog states in 10B were studied in the excitation energy range of E=8.7-12.1 MeV using the reaction 1H(9Be,alpha)6Li*(T=1, 0+, 3.56 MeV). An R-matrix analysis was used to extract parameters for the states observed in the (p,alpha) excitation function. Five T=1 stat…