Genetics and Responsibility: To Know the Criminal From the Crime

The use of the t6O(o,o)160 elastic scattering resonance reaction forthe study of low concentration of oxygen such as found in interfacesin silicon technology is described. We have investigated the depth resolution and the limit of the sensitivity that can be obtained with thismethod. The method has been applied to the study of AlrQ{r "sandwich" film structures and to Au and amorphous Ge contacts to silicon

Anharmonic double-phonon excitations in the interacting boson model

Double-$\gamma$ vibrations in deformed nuclei are analyzed in the context of the interacting boson model. A simple extension of the original version of the model towards higher-order interactions is required to explain the observed anharmonicities of nuclear vibrations. The influence of three- and four-body interactions on the moments of inertia of ground- and $\gamma$-bands, and on the relative position of single-$\gamma$ and double-$\gamma$ bands is studied in detail. As an example of a realistic calculation, spectra and transitions of the highly $\gamma$-anharmonic nuclei $^{164}$Dy, $^{166}$Er, and $^{168}$Er are interpreted in this approach.Comment: 38 pages, TeX (ReVTeX). 15 ps figures. Submitted to Phys. Rev.

Multi-Phonon γ\gamma-Vibrational Bands and the Triaxial Projected Shell Model

We present a fully quantum-mechanical, microscopic, unified treatment of ground-state band and multi-phonon $\gamma$-vibrational bands using shell model diagonalization with the triaxial projected shell model. The results agree very well with data on the g- and $\gamma$-band spectra in $^{156-170}$Er, as well as with recently measured $4^+$ 2-phonon $\gamma$-bandhead energies in $^{166}$Er and $^{168}$Er. Multi-phonon $\gamma$-excitation energies are predicted.Comment: 4 pages, 4 figures, submitted to Phys. Lett.

Spectroscopic studies of Dy-168,170 using CLARA and PRISMA

Preliminary results from an experiment aiming at Dy-170. Submitted to the LNL Annual Report 2008.Comment: 2 pages, 4 figures, Submitted to the LNL Annual Report 200

Search for proton emission of the isomeric 10+ state in 54 Ni

9 pags., 7 figs., 1 tab.Several experiments were conducted at the 10 MV Van-de-Graaff tandem accelerator at the Institute of Nuclear Physics, Cologne, to detect proton emission from the isomeric 6457-keV 10 state in Ni. Excitation functions for two fusion–evaporation reactions were measured to maximise the population of the rare two-neutron evaporation channel from a Ni compound nucleus. The search for delayed proton emission was based on the Si (Si , 2 n)Ni reaction at a beam energy of 70 MeV. For this reaction, a cross-section limit for the population of the 10 state in Ni and its proton-decay branch was determined to be σ< 22 nb.Open Access funding provided by Projekt DEAL. We would like to thank the accelerator staff at the University of Cologne for the efforts to deliver heavy-ion beams of excellent quality, as well as the Swedish Research Council (contract VR 2008-4240 and VR 2016- 3969) for financial support

Onset of high-spin rotational bands in the N=Z nucleus Ga 62

The fusion-evaporation reaction Si28+Ca40 at 122 MeV beam energy was used to populate high-spin states in the odd-odd N=Z nucleus Ga62. With the combination of the Gammasphere spectrometer and the Microball CsI(Tl) charged-particle detector array the decay scheme of Ga62 was extended beyond 10 MeV excitation energy. The onset of band structures was observed. These high-spin rotational states are interpreted and classified by means of cranked Nilsson-Strutinsky calculations

Triaxial Superdeformation in 163 Lu

Abstract High-spin states in 163 Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality ( γ ≈±20°)

Hindered E4 decay of the 12+ yrast trap in 52Fe

AbstractThe γ decay of the 12+ yrast trap in 52Fe has been measured for the first time. The two E4 γ-branches to the 8+ states are hindered with respect to other B(E4) reduced transition probabilities measured in the f7/2 shell. The interpretation of the data is given in the full pf shell model framework, comparing the results obtained with different residual interactions. It is shown that measurements of hexadecapole transition probabilities constitute a powerful tool in discriminating the correct configuration of the involved wavefunctions

High-precision mass measurements for the isobaric multiplet mass equation at A=52

Masses of Co-52, (52)Com, Fe-52, Fe-52(m), and Mn-52 have been measured with the JYFLTRAP double Penning trap mass spectrometer. The isobaric multiplet mass equation for the T = 2 quintet at A = 52 has been studied employing the new mass values. No significant breakdown (beyond the 3 sigma level) of the quadratic form of the IMME was observed (chi(2)/n = 2.4). The cubic coefficient was 6.0(32) keV (chi(2)/n = 1.1). The excitation energies for the isomer and the T = 2 isobaric analog state in Co-52 have been determined to be 374(13) keV and 2922(13) keV, respectively. The measured mass values for Co-52 and (52)Com are 29(10) keV and 16(15) keV higher, respectively, than obtained in a recent storage-ring experiment, and significantly lower than predicted by extrapolations. Consequently, this has an impact on the proton separation energies for Co-52 and Ni-53 relevant for the astrophysical rapid proton capture process. The Q value for the proton decay from the 19/2(-) isomer in Co-53 has been determined with an unprecedented precision, Q(p) = 1558.8(17) keV.Peer reviewe

Hindered E4 decay of the 12+ yrast trap in 52Fe

Abstract The γ decay of the 12 + yrast trap in 52Fe has been measured for the first time. The two E4 γ-branches to the 8 + states are hindered with respect to other B ( E 4 ) reduced transition probabilities measured in the f 7 / 2 shell. The interpretation of the data is given in the full pf shell model framework, comparing the results obtained with different residual interactions. It is shown that measurements of hexadecapole transition probabilities constitute a powerful tool in discriminating the correct configuration of the involved wavefunctions