Search results for "Reaction"
showing 10 items of 6134 documents
Coexisting structures in 119I
1997
Abstract High-spin structures of 119 I have been studied by using 13 C and 15 N induced reactions. In all, fifteen ΔI = 1 or 2 bands belonging to 119 I were found. No evidence was found for bands with collective oblate shape, instead, all the observed rotational bands were interpreted to possess a collective prolate shape. A rich tapestry of noncollective states of both negative and positive parity was observed. Based on TRS calculations various configurations at β 2 ≈ 0.17 and γ = 60° were assigned to these states.
An experiment on the electroproduction of multi-hadron final states
1995
Abstract Electroproduction of final states including protons and pions was measured on 12C in close to 4π geometry using a BGO crystal ball at the 3-spectrometer facility at MAMI. The energy transfer regime studied at three incident electron energies ranged from the quasielastic proton knockout to the quasifree Δ excitation region. The 3-momentum of the virtual photon ranged from about 400 to 800 MeV/c. The performance of the experimental setup is discribed and missing energy distributions of the reactions 12C(e,e′p) and 12C(e,e′pp) are presented.
0+-0+transition in charged photopion reactions
1991
In the near-threshold region for the (\ensuremath{\gamma},${\mathrm{\ensuremath{\pi}}}^{\ifmmode\pm\else\textpm\fi{}}$) reaction the spin-flip (Kroll-Ruderman) term dominates most nuclear reactions. The smaller non-spin-flip term is of considerable interest because it is very sensitive to the reaction dynamics and in particular to the \ensuremath{\Delta} channel, even in the near-threshold region. We propose to study the non-spin-flip term via the ${0}^{+}$\ensuremath{\rightarrow}${0}^{+}$ transition in the $^{14}\mathrm{C}$(\ensuremath{\gamma},${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$${)}^{14}$N reaction; the cross section is shown to be insensitive to the details of nuclear …
Production of hypernuclei in multifragmentation of nuclear spectator matter
2007
In peripheral collisions of relativistic heavy ions highly excited spectators containing Lambda-hyperons can be produced. Such strange spectator matter may undergo a break-up into many fragments (multifragmentation) as it is well established for ordinary nuclear systems. We generalize the statistical multifragmentation model, previously successfully used for the description of experimental data, for the case of hypernuclear systems. We predict relative yields of hypernuclei and the main characteristics of such a break-up. We point at a connection of this phenomenon with a liquid-gas phase transition in hypermatter.
Transfer and neutron capture reactions toIr194as a test of Uν(6/12)⊗Uπ(6/4)supersymmetry
2008
The structure of $^{194}\mathrm{Ir}$ is investigated via ($n,\ensuremath{\gamma}),(n,{e}^{\ensuremath{-}}),(d,p)$, and ($\stackrel{\ensuremath{\rightarrow}}{d},\ensuremath{\alpha}$) spectroscopy. The use of different methods leads to an almost complete level scheme up to high excitation energies including \ensuremath{\gamma}-decay and spin-parity assignments. A reanalysis of the formerly published ($n,\ensuremath{\gamma}$) data was triggered by our new ($d,p$) and ($\stackrel{\ensuremath{\rightarrow}}{d},\ensuremath{\alpha}$) transfer reactions. The experimental level scheme is compared to predictions using extended supersymmetry. Herein, the classification of states was done according to q…
Virtual photons and electrodisintegration of the deuteron
1982
The validity of the virtual photon concept in the analysis of deuteron electrodisintegration for equivalent photon energies up to 300 MeV is investigated. The deuteron and the final state interaction are described by the consistent nonrelativistic calculation of Fabian and Arenhoevel neglecting the effects of meson exchange currents and isobar configurations. We find that in well defined kinematic domains the use of the virtual photon concept is justified in extracting photodisintegration cross sections.
Measurement of the magnetic form factor of the neutron
1993
The [sup 2]H([ital e],[ital e][prime][ital n])[sup 1]H quasielastic cross section was measured at [ital Q][sup 2] values of 0.109, 0.176, and 0.255 (GeV/[ital c])[sup 2]. The neutron detection efficiency was determined by the associated particle technique with the [sup 2]H([gamma],[ital pn]) reaction for each of the three neutron kinetic energies. These [sup 2]H([ital e],[ital e][prime][ital n]) measurements of the coincidence cross sections are the first at low [ital Q][sup 2]. The cross sections are sensitive primarily to the neutron magnetic form factor [ital G][sub [ital M]][sup [ital n]] at these kinematics. The extracted [ital G][sub [ital M]][sup [ital n]] values have smaller uncerta…
Out-of-plane emission of nuclear matter in Au+Au collisions between 100 and 800 AMeV
1997
We present new experimental results concerning the azimuthal distributions of proton-likes, light and intermediate mass fragments at midrapidity for Au(100-800 AMeV)+Au collisions measured with the FOPI phase-I detector at GSI in Darmstadt. The azimuthal distributions are investigated as a function of the collision centrality, the incident energy, the fragment charge and transverse momentum. The azimuthal anisotropy is maximum for impact parameters around 7 fm. Intermediate mass fragments present a stronger out-of-plane emission signal than light fragments and a saturation is reached for Z greater than or equal to 4. The azimuthal anisotropy increases with the fragment transverse momentum a…
Interplay of quasiparticle and phonon excitations in 181Hf observed through (n,γ) and reactions
2002
Abstract Nuclear levels of 181 Hf were investigated in the range up to 3 MeV excitation energy by (n, γ ) and (d,p) reactions. Over 170 levels and about 390 γ -transitions were established most of them for the first time. 25 rotational bands were identified. Comparison of the results of the two reactions yields information on the fine structure in the fragmentation of Nilsson strength. The states below 2 MeV with the most complete spectroscopic information were interpreted in terms of the Quasiparticle Phonon Model (QPM). Excitation energies, electromagnetic transition rates, γ -branchings and spectroscopic factors are discussed in connection with their possible structure.
Nuclear structure of 187W studied with (n,γ) and (d,p) reactions
2008
Abstract The level structure of 187 W has been studied using prompt and delayed gamma–gamma coincidences from thermal neutron capture in 186 W and also measuring the ( d , p ) reaction. From these data and those of previous studies a total of 170 levels (121 connected by γ transitions) have been established for energies below 2.35 MeV. Some of these levels have been grouped into rotational bands built on 14 intrinsic states of quasi-particle and quasi-particle plus phonon character. Of particular interest has been the identification of “quasi bands” with inverse spin sequence based on the newly established isomeric 11 / 2 + state at 410.1 keV. Although the DWBA analysis permitted definite s…