Operation results of the Dynamitron Tandem at Bochum
TL;DR: The performance of the Dynamitron-Tandem accelerator at Bochum with respect to beam energy resolution, stability and reproducibility, and beam intensity is reported in this paper.
About: This article is published in Nuclear Instruments and Methods.The article was published on 1974-11-01. It has received 21 citations till now. The article focuses on the topics: Excitation function.
Citations
More filters
01 Mar 1982
TL;DR: In this article, the authors investigated the elastic scattering process and capture reaction for groundstate γ-ray transition with the use of an intense 12C beam and a windowless and 4He recirculating gas target system.
Abstract: The capture reaction4He(12C, γ)16O (E
cm= 134–338 MeV) as well as the elastic scattering process4He(12C,12C)4He (E
cm=144–338 MeV) have been investigated with the use of an intense12C beam and a windowless and4He recirculating gas target system The measurements involved two large NaI(T1) crystals in close geometry to an extended gas target, whereby angle-integrated γ-ray yields were obtained A large area plastic detector was used for the suppression of time-independent background A search for cascade γ-ray transitions was carried out by coincidence techniques The measurement of absolute cross sections is also reported Theoretical fits of the excitation function for the groundstate γ-ray transition requireE1 as well asE2 capture amplitudes, which are of equal importance at stellar energies This result increases significantly the stellar burning rate of4He(12C, γ)16O and leads to16O as the dominant product at the end of helium burning in massive stars The observed capture yield to the 692 MeV state is dominated by the direct capture mechanism and plays a small role at stellar energies
84 citations
TL;DR: In this paper, the elastic scattering of alpha particles from 12C has been investigated for 35 angles in the range θlab = 22° to 163° and for 51 energies at Eα = 1.0 to 6.6 MeV.
81 citations
TL;DR: In this article, the partial cross sections of heavy residual nuclei produced in the heavy ion fusion of 12C+20Ne have been measured at 6-15 MeV viaγ-ray spectroscopy with a Ge(Li) detector.
Abstract: The partial cross sections of heavy residual nuclei produced in the heavy ion fusion of12C+20Ne have been measured atE
c.m.=6–15 MeV viaγ-ray spectroscopy with a Ge(Li) detector. Windowless and recirculating gas target systems have been used. The dominant residual nuclei are24Mg,27Al,28Si,30Si,30P and31P, which arise from two- and three-body breakups in the exit channels. The observed excitation functions are smooth in their energy dependence and give no indications for the existence of pronounced resonance structures, in contrast to theoretical predictions. The Coulomb excitation of20Ne served as an intrinsic calibration standard in the determination of absolute partial and total fusion cross sections. The same experimental set-up was also used in the reaction studies of16O+16O atE
c.m.=7–14 MeV, going through the same compound nucleus32S at similar excitation energies. The observed energy dependence in the excitation functions is in good agreement with previous work. The total fusion cross section agrees fairly well with two sets of values reported previously, but deviates significantly from other reported absolute cross section values. The relative evaporation distributions of the residual nuclei are similar for both heavy ion reactions. However, the ratio of their total fusion cross sections deviates from model predictions and suggests that compound nucleus formation does depend on the microscopic structure of the colliding nuclei in the entrance channel. From the observed energy dependence of the above ratio, particularly at subcoulomb energies, geometrical effects in the entrance channel (due to deformed and spherical nuclei) appear to be weak. The astrophysical aspects of the data in the context of late stellar nucleosynthesis are discussed.
52 citations
TL;DR: In this article, the energy calibration of the beam analyzing magnet at the 4 MV Dynamitron tandem accelerator in Bochum has been carried out over a wide magnetic field range (B =24 −124 kG) using the well-known energies of several proton induced resonance reactions.
38 citations
TL;DR: In this article, the reaction 22 Na(p,γ) 23 Mg has been investigated in the energy range E p = 0.17-1.29 MeV using a 22 Na implanted target, a D 2 O threshold detector, and NaI(Tl) and Ge detectors.
37 citations
References
More filters
CERN1
TL;DR: A quantitative description of the statistical fluctuations in the region of overlapping resonances of nuclear cross sections is given in this article, where general nuclear reaction theory is used in order to systematically obtain a separation of direct interactions and compound nuclear contributions.
399 citations
163 citations
TL;DR: In this paper, the average coherence energy Γ of 18 keV corresponds to a lifetime of 3.7 × 10 −20 sec for the compound nucleus 38 Ar excited at 21 MeV.
57 citations
44 citations