L. Zolnai

Pixase: A computer package for evaluation of PIXE spectrum series: Part II. Calculation of the effective cross sections for X-ray production

Abstract The second part of the programme package written for the evaluation of PIXE spectra [1] is described. The programme which calculates the effective cross sections for X-ray production can be applied for the cases of thin and thick samples. The fast and simple applicability of the programme is assured by stored files of the necessary atomic physical quantities and ionization cross sections calculated by the programme. A few examples are shown for the application of the programme where the data obtained are compared with the results from other authors.

Evidence for multiple band terminations in 102Pd

Abstract The level structure of 102 Pd has been investigated using data collected with the Eurogam 2 array. Several cascades of γ-rays have been established up to high spins. Termination of rotational bands has been observed at I π = 28 − and 32 + , and tentatively at I π = 38 + and 42 + . The nucleus 102 Pd is the first case where rotational bands built on valence space configurations are followed from spin close to zero up to termination and, at higher spins, a smooth rotational band which appears to terminate is built on core excited configurations.

PIXASE: A computer package for evaluation of PIXE spectrum series. Part I: Spectrum evaluation

Abstract The spectrum evaluation part of a programme package for PIXE spectrum analysis is discussed. Attention is focussed on the method used for the evaluation of the pileup contribution in the PIXE spectra. Different methods for the evaluation of series of the PIXE spectra measured on samples having identical matrix composition are described.

High-spin study of 128Ce and systematics of quasiparticle pair alignment

Abstract High-spin states have been studied in 128 Ce, produced in the 100 Mo( 32 S,4n) reaction, using the Euroball γ -ray spectrometer. A quadruples analysis ( γ 4 ) of the data has extended several bands to high spin. Systematics of quasiparticle alignments in cerium isotopes and relevant isotonic chains are discussed and compared to Woods–Saxon cranking calculations.

Low-lying levels and high-spin band structures in 102Rh

Abstract Levels in 102 Rh have been populated in the reaction 70 Zn+ 36 S at 130 MeV. The level structure of 102 Rh has been investigated using the EUROGAM II array. Low-lying states and four high-spin bands have been identified. The configurations of low-lying levels and two-quasiparticle bands are interpreted in the frame of the interacting boson-fermion-fermion model. The four observed band structures are also compared with cranked shell model calculations using a modified oscillator potential.

{gamma}-Spectroscopy and Radioactive Beams: How To Perform Channel Selection ?

An experiment has been performed using a SPIRAL 76Kr radioactive beam at GANIL to investigate rare‐earth nuclei near the proton drip‐line. The EXOGAM gamma array was coupled with the DIAMANT light charged‐particle detector and the VAMOS spectrometer. We report here on the powerful of this setup to extract fusion‐evaporation γ‐rays from a large beam contamination.

Three-quasiparticle rotational bands in 101Rh: IBFBPM description and signature inversion of the πg9/2 orbital

Abstract High- and intermediate-spin level structures of the 101 Rh nucleus have been studied using the reaction 70 Zn+ 36 S at 130xa0MeV bombarding energy. γ -rays were detected with the EUROGAM II detector array. Three new ΔI =1 rotational bands have been observed in this nucleus. The deduced level scheme is compared with results of calculations using Interacting Boson–Fermion plus Broken Pair Model. The model calculations give a consistent description of the one- and three-quasiparticle states providing fair agreement between the observed and calculated level energies and branching ratios. Experimental Routhians of the new high-spin bands and the πg 9/2 νh 11/2 bands in the neighbouring Rh and Ag nuclei have been found to exhibit signature inversion. This signature inversion can be interpreted qualitatively as the inversion of the two signatures of the proton g 9/2 orbital caused by triaxial nuclear shape with large positive γ parameter.

Band terminations in the doubly odd nucleus102Rh

SummaryThe level structure of102Rh has been investigated using the EUROGAM Phase2 array. Bands observed up to high spins are discussed in terms of band terminations.102Rh is the first doubly odd nucleus belowZ = 50 in which band terminations are established.

Neutral particles in the beam of a single ended van de graaff accelerator

Abstract Neutral particles have been observed in the extension to the entrance channel of the magnetic analyzer. They may originate from charge exchange processes in different parts of the trajectories of accelerated ions. On the basis of I 0 / I analyzed , I 0 / I total curves and secondary electron emission coefficients, conclusions are drawn on the presence of neutral particles in the acceleration tube.