The154Sm(28Si, Mg) and154Sm(16O, C) reactions atE/B∼1.6 (original) (raw)

C12(O16, α)Mg*24reaction in the energy regionEc.m.=26.6 to 42.9MeV

Physical Review C, 1983

The '2C+' 0 resonance structure in the 'Si nucleus is examined by means of the '~C(' O, a)'~Mg reaction excitation functions in the energy range E, =26.6 to 42.9 MeV in 430 keV steps at ebb-7. 5'. We could identify 64 discrete states in "Mg up to 31.7 MeV of excitation energy. The excitation functions show abundant structure over the entire energy range. The summed excitation functions, which tend to average out statistical fluctuations, show pronounced intermediate structure enhancement in the cross section at E, =29.5, 32.2, and 35 MeV and indicate the presence of a smaller peak at 37.3 MeV. The widths of these structures are about 1 MeV, which is intermediate between the value expected from ion-ion potential resonances and statistical fluctuations. The nonstatistical character of these structures is reinforced by some statistical tests and by the correlations in energy and width found in several exit channels. Our data also suggest a possible structural relationship between the 'Si resonances and certain ' Mg final states. NUCLEAR REACTIONS ' C(' O, a) Mg~; measured o(E) to states up to 31.7 MeV of excitation energy for E, =26.6 to 42.9 MeV in 430 keV steps, H~,b-7. 5'. Nonstatistical structure observed.

The (d, 6Li) reaction on 24Mg, 26Mg and 28Si at 35 MeV

Nuclear Physics A, 1976

Data for the (d, eLi) reaction on targets of 24Mg, 2eMg and 2sSi have been obtained at 35 MeV bombarding energy. Angular distributions were measured for low-lying statesin the residual nuclei. Tern-range distorted-wave Born approximation (DWBA) calculations have been used to analyze the daJ_a_, The DWBA calculations account for the shapes of the experimental distributions reasonably well. The observation of significant population of unnatural parity states implies, however, that other transfer mechanisms may be important. The experimental spectrmcopic factors are in qualitative agreement with those obtained from SU(3) theory. E ] NUCLEAR REACTIONS "'Mg, "Mg, "8Si(d: eLi), E~ 35 MeV; measured or(0). ' [ a°.a:~Ne, 24Mg levels deduced S~.

Reaction mechanisms in 24Mg+ 12C and 32S+ 24Mg

2009

The occurence of "exotic" shapes in light N=Z α-like nuclei is investigated for 24 Mg+ 12 C and 32 S+ 24 Mg. Various approaches of superdeformed and hyperdeformed bands associated with quasimolecular resonant structures with low spin are presented. For both reactions, exclusive data were collected with the Binary Reaction Spectrometer in coincidence with EUROBALL IV installed at the VIVITRON Tandem facility of Strasbourg. Specific structures with large deformation were selectively populated in binary reactions and their associated γ-decays studied. The analysis of the binary and ternary reaction channels is discussed.

Binary reaction decays from 24 Mg + 12 C

Phys. Rev. C 80 034604, 2009

Charged-particle and γ decays in 24 Mg * are investigated for excitation energies where quasimolecular resonances appear in 12 C + 12 C collisions. Various theoretical predictions for the occurrence of superdeformed and hyperdeformed bands associated with resonance structures with low spin are discussed within the measured 24 Mg * excitation energy region. The inverse kinematics reaction 24 Mg + 12 C is studied at E lab (24 Mg) = 130 MeV, an energy that enables the population of 24 Mg states decaying into 12 C + 12 C resonant breakup states. Exclusive data were collected with the Binary Reaction Spectrometer in coincidence with Euroball IV installed at the Vivitron tandem facility at Strasbourg. Specific structures with large deformation were selectively populated in binary reactions, and their associated γ decays studied. Coincident events associated with inelastic and α-transfer channels have been selected by choosing the excitation energy or the entry point via the two-body Q values. The analysis of the binary reaction channels is presented with a particular emphasis on 24 Mg-γ, 20 Ne-γ , and 16 O-γ coincidences. New information (spin and branching ratios) is deduced on high-energy states in 24 Mg and 16 O, respectively.

Reactions induced byC13onC12,O16,Si28, andS32

Physical Review C, 1976

V) 28Si(13C 13C)28Si 28Si(13C 12C)29Si 28Si(13C 12C)29Sitit (1 27 M V) 28S (&3C &4N)2~AI 2S(C &3C)32S "S("C,"C)"S, "S("C""C)"S~(0.841 MeV), and "S("C,'"N)"P have been measured in fine steps between 0(,b-4' and 8""=40 at the bombarding energy of 36 MeV. Elastic scattering data are fitted by opticalmodel calculations and the parameters of the potential are determined. The neutron-transfer and protonpickup reaction cross sections are compared with the predictions of the exact finite-range distorted-wave Bornapproximation. The calculated angular distributions reproduce the gross features of the data but not the details. The quantitative agreement of the determined spectroscopic factors with the spectroscopic factors found from light-ion reactions varies from excellent to poor. The a-transfer reaction "C("C,'Be)' 0 has been analyzed using cluster-model form factors. The agreement between theory and experiment is poor. The measured angular distribution is, however, well described by~P, s(coss}~' NUCLEAR REACTIONS Elastic scattering, neutron stripping, and proton pickup induced by 36 MeV '3C on S, 8Si,~60, and '2C, and i2C(~3C, Be)~60 measured at Oi,b =4'-40', 48 iab =1'. Optical-model parameters, exact finite-range DKBA, spectroscopic factor s.

Structure of 24^{24}24Mg Excited States and Their Influence on Nucleosynthesis

Acta Physica Polonica B

The main idea of the two presented experiments is to study the decay of resonances in 24 Mg at excitation energies above the 12 C+ 12 C decay threshold, in the astrophysical energy region of interest. The measurement of the 12 C(16 O,α) 24 Mg* reaction was performed at INFN-LNS in Catania. Only the α+ 20 Ne decay channel of 24 Mg is presented here, because it was a motivation for conducting a new experiment, a study of the 4 He(20 Ne, 4 He) 20 Ne reaction, performed at INFN-LNL in Legnaro. Some preliminary results of this measurement are also presented.

Comparison of complementary reactions in the production of Mt

Physical Review C, 2009

The new reaction 208 Pb(59 Co,n) 266 Mt was studied using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. A cross section of pb was measured at a compound nucleus excitation energy of 14.9 MeV. The measured decay Disclaimer: This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.

The 721, 809, 839 and 954 keV resonances of the Mg26 (p, γ) reaction

Nuclear Physics, 1962

Gamma ray spectra and angular correlation measurements have been obtained at the 721, 809, 839 and 954 keV resonances of the MgZS(p, F) reaction. On the basis of these measurements, spins have been assigned to the 809({), 839(½) and 954({) keV resonances No definite assignment could be made to the 2 2 MeV level of A1 zT.

The27Al(n, d)26Mg reaction at 22 MeV

Zeitschrift f�r Physik A Atomic Nuclei, 1990

Deuteron spectra from the reaction 27Al(n, d)Z6Mg has been measured at reaction angles 0~ 60 ~ with a spectrometer comprising three multiwire proportional counters followed by a curved plastic scintillator. Spectra were obtained with an energy resolution of ~0.7 MeV and an angle resolution of ~5 ~ Angular distributions for transitions to the ground state and excited states at 1.81, 2.93 and 4.3 MeV in Z6Mg were obtained. Distorted waves analysis of the angular distributions yield spectroscopic factors of 0.29(8), 0.9(3), 0.18(7) and 1.9(6) for the ground and excited states, respectively. The results are compared with previous (d, 3He) and (n, d) measurements, and with theoretical predictions.