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A combined mathematical model was developed for the regional-scale dynamics of gaseous admixtures and aerosols in the atmosphere. The model incorporates the following modules: thermo-hydrodynamic equations for meso-scale atmospheric processes in the non-hydrostatic approximation; transport of gaseous admixtures and aerosols, with allowance for photochemical transformation and binary homogeneous nucleation; and kinetic processes of condensation/evaporation and coagulation. Particular emphasis is given to the mechanisms of new-particle formation through binary homogeneous nucleation of drops of sulfuric acid and water vapor. By using this model, numerical experiments were performed to investigate spatio-temporal variations in the concentrations of gaseous admixtures and aerosols, as well as the formation of fine aerosol clusters in the Lake Baikal (Russia) and Antwerp (Belgium) areas due to strong industrial emission sources. The results of the numerical experiments are analyzed.

Despite the scarce effect of speed limit reduction measures on total mass PM10 and PM2.5 concentrations, it is shown that the effect on the probably more hazardous component elemental carbon (EC) is more important which means that, from the viewpoint of health benefit, speed reductions during smog episodes may well be justified. Especially in the very dense highway network in Flanders with a 60% share of diesel cars (the highest in Europe) a speed limit reduction from 120 to 90 km/h during winter smog episodes on selected sections of Flemish highways leads to a significant decrease of the EC concentrations near those highways. Key findings are that the decrease in EC depends on the distance from the highways. In the direct vicinity of the highways, a decrease compared to the base-line scenario where no speed limit changes were implemented of up to 30% of the EC concentrations is modeled. Within a distance of 1500 m of the concerned highway sections there is an average decrease in EC of 0.18 μg m−3 affecting about 1 million people living in these areas. When the speed limit reduction measure is in force, the EC exposure of about 300,000 people decreases by at least 5% and 7500 people experience a decrease of 15% or more.

The $ \beta^{{+}}_{}$ /EC decay of 189m, gPb has been studied at the ISOLDE facility using nuclear spectroscopy and in-source laser spectroscopy. A level scheme of 189Tl has been built from $ \gamma$ - $ \gamma$ coincidence relationships and information on the feeding of some excited levels of 189Tl provided by the hyperfine spectra obtained from laser ionization. The half-lives of both the 13/2+ and 3/2- 189Pb isomers have been estimated to be T 1/2 = 50±3 s and T 1/2 = 39±8 s, respectively. Calculations have been performed for different oblate and prolate nuclear deformations using an axial-rotor coupled to one-quasiparticle model, a structure has been suggested for the low-lying levels of the 189Tl nucleus.

Air quality modeling can help to improve understanding of scale interactions related to meteorology, transport, emissions, formation, removal, and other processes taking place at local, urban, and regional scales. For the local scale, we used the coupling of a street canyon model with a Gaussian dispersion model to study the interactions of emissions and concentrations in urban streets and surrounding urban neighborhoods. The model combination was applied to a city quarter in Ghent, Belgium, and showed that up to 40% of the PM2.5 concentrations inside street canyons were caused by emissions from the surrounding streets. For the urban scale, the AURORA model has been used successfully in assessments of urban air quality for entire cities or urbanized areas. It has been applied to the Ruhr area in Germany to evaluate the impact of compact or polycentric cities versus the impact of urban sprawl developments. Results for ozone and PM10 showed that compact city structures may have more adverse effects in terms of air pollution exposure. For the regional scale, the EUROS model was used to study the urban and regional-scale interactions that are important in simulating concentrations of ozone, PM2.5, and PM10. It has been applied to study seasonal changes in aerosol concentrations in Flanders. High secondary aerosol concentrations were found during summer. This contribution was related to large contributions from outside the region, showing the importance of the continental scale when studying regional air quality problems.

Evidence for the decay of non-yrast states in 254No has been observed for the first time in an experiment performed at the University of Jyvaskyla. The experiment employed the JUROGAM array of germanium detectors coupled to the gas-filled recoil separator RITU and the focal-plane spectrometer GREAT. The ground-state rotational band has been tentatively extended up to a spin of 24ℏ and has a smoothly behaving dynamical moment of inertia. It is speculated that the observation of high-energy γ-rays is due to the decay of a K = 3 band-head state.

The exploitation of the recoil-decay tagging (RDT) technique has reinvigorated experimental investigations of the shape coexistence phenomenon in heavy neutron-deficient nuclei. In a recent experiment using the JUROGAM and GREAT spectrometers in conjunction with the RITU gas-filled separator, excited states have been investigated in the light platinum isotopes. In addition to extending the yrast sequences in 170Pt and 172Pt, the first observation of excited states in the odd-N isotopes, 169Pt and 173Pt, is reported. The bands are discussed in terms of trends in level excitation energies as a function of neutron number.

Iridium nuclei at and beyond the proton drip line have been studied via fusion evaporation reactions. A reaction of 92Mo(78Kr, p2n) at a beam energy of 360 MeV and target thickness 500 µg cm−2 was employed to study 167,167mIr. A reaction of 112Sn(58Ni, p2n) at a beam energy of 266 MeV and target thickness 500 µg cm−2 was used to study 169,169mIr. The experiments were performed at the University of Jyvaskyla utilizing the RITU separator in conjunction with the focal plane GREAT spectrometer and the JUROGAM Ge array at the target position. Excited states feeding both the ground state and isomeric state in 169Ir, excited states feeding the ground state of 167Ir and the ground state alpha decay of 165Re have been observed for the first time along with excited states feeding 167mIr. Experimental spectroscopic factors and reduced widths have been obtained for the proton and alpha decay of these nuclei.

The 3/2- isomer in 185Pb and states above it have been populated in the α-decay of 189Po. The observed α-decay strengths to and the electromagnetic decay properties of the excited states in 185Pb have been combined with Potential Energy Surface and Particle-Plus-Rotor calculations to propose configuration assignments. It is suggested that the α-decaying isomer of 189Po is of prolate origin and that the prolate configuration becomes very low in energy in 185Pb.

A new measurement of the 200Fr α-decay half-life, with improved accuracy compared to previous measurements, has been carried out at the Isolde-CERN on-line mass separator. A half-life of 49(4) ms has been obtained, which is substantially different from earlier literature values. For the 196At daughter decay, a half-life of 389(54) ms and an α branching ratio bα = 94(5)% were measured. In addition, the half-lives of 201, 203, 205Fr and 197,199At are reported.

Novel methods for internal conversion electron and β -decay spectroscopy at the focal plane of a recoil separator are discussed. As an example the experimental data collected at the focal plane of the velocity filter SHIP (GSI, Darmstadt) are presented and compared with the results of the GEANT Monte Carlo simulations. It is shown that the simultaneous detection of conversion electrons, γ -rays and X-rays is possible, which significantly broadens the range of applications of this and similar systems.

The very neutron-deficient 91,92,93Rh and 90,91Ru nuclei were produced in 58Ni(36,40Ar, xn yp) fusion-evaporation reactions. Reaction products leaving the target were stopped in a gas cell and selectively laser ionised before mass separation using the LISOL setup. Data were collected in singles and coincidence formats to investigate $\beta$ -delayed and isomeric $\gamma$ decays. Ground-state decays of 91,93 Rh to excited states in the daughter nucleus were identified for the first time and the decay schemes of 90,91 Ru were expanded. The low-spin isomeric decay of 92Rh was identified for the first time and detail added to the decay scheme of the known high-spin state. Results are discussed in terms of comparison with shell model calculations. $\beta$ -delayed proton activity in the lighter 90Rh and 89Ru isotopes was also investigated and upper limits for this decay mode in these two nuclei have been included.

Neutron-rich thallium, lead, and bismuth isotopes were investigated at the ISOLDE facility. After mass separation and resonant laser ionisation of the produced activity, new spectroscopic data were obtained for 215,218 Bi and 215 Pb. An attempt to reach heavy thallium had to be abandoned because of a strong francium component in the beam that gave rise to a neutron background through (α,n) reactions on the aluminium walls of the experimental chamber.

A new high-spin isomer in 215Bi, with a half-life of 36.9(6) s, has been identified at the PSB-ISOLDE on-line mass separator using the pulsed-release technique combined with the element selective RILIS source. A decay scheme of $^{215{\rm m}}$ Bi was constructed and complemented with the low-spinstructure observed in $^{215{\rm g}}$ Bi decay. The population of a cascade on top of the $\left( \nu g_{9/2} \right)^5_{9/2+}$ level in 215Poprovides evidence for Gamow-Teller $\beta$ -decay of the high-spin 215Bi isomer.

Alpha-decay of the new nuclide 184Bi has been studied in the complete-fusion reaction 93Nb(94Mo, 3n)184Bi at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil- $\alpha$ , recoil- $\alpha$ - $\gamma$ analysis and excitation functions measurements. Two $\alpha$ -decaying isomeric states in 184Bi with half-life values of 13(2) ms and 6.6(1.5) ms were identified. The $\alpha$ -branching ratio of 180Tl was deduced for the first time as $b_\alpha = (2 --12)\%$ . Improved data on the fine-structure $\alpha$ -decay of 186Bi were obtained in the 93Nb(95Mo, 2n)186Bi reaction. A similarity of the decay energies and half-life values of 184,186Bi is pointed out and a possible explanation for this effect is suggested.

Detailed fine-structure $\alpha$ -decay studies of 188,190Bi were performed using the complete-fusion reactions of 50,52Cr ions with a 142Nd target at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil- $\alpha$ , recoil- $\alpha$ - $\gamma$ /X-ray and excitation function measurements. Improved data on the $\alpha$ -decay of 188,190Bi were obtained and a number of new low-lying excited states in the daughters 184,186Tl were observed. An intruder, presumably 10- state was identified in 184Tl, extending the systematics of such states in the odd-odd Tl nuclei beyond the neutron mid-shell at N = 104. Some technical aspects of experiment at recoil separators are also discussed.

Exotic, neutron-rich proton-induced spallation products of 232Th and 238U obtained from the PS Booster ISOLDE facility have been investigated by $\gamma$ - $\gamma$ , $\alpha$ - $\gamma$ coincidence and spectrum-multiscaling measurements. A new method for the reduction of isobaric contamination enabled to study the unknown region beyond 208Pb for the decay chain A = 217. A new isotope 217Bi with a half-life of $98.5 \pm 0.8$ s was discovered and its $\beta$ -decay studied. For the first time, a half-life value of $1.53 \pm 0.03$ s for the $\alpha$ -decay of 217Po was measured.

Gamma rays from excited states of 190Po have been observed using the Jurosphere Ge-detector array coupled to the RITU gas-filled separator. They were associated with a collective band which from spin 4 onwards resembles the prolate rotational bands known in the isotones 188Pb and 186Hg. This indicates that in 190Po the prolate configuration becomes yrast above I = 2. The experimental results are interpreted in a two-band mixing calculation and are in agreement with α-decay data and potential energy surface calculations.

In recent years (1996-2001) the recoil-decay tagging technique has been employed with great success at the Department of Physics of the University of Jyvaskyla. Various arrays of germanium detectors have been coupled to the RITU gas-filled separator in order to study nuclei far from stability. An overview of the physics studied with these arrays, along with discussion of technical development of the RITU separator, is presented. Even with a comparatively modest array of germanium detectors it has been possible to study nuclei produced with cross-sections as low as 200 nb.

The JYFL gas-filled recoil separator RITU, combined with Ge detector arrays and a SACRED magnetic solenoid spectrometer, has been successfully employed in recoil-decay-tagging (RDT) experiments in order to probe structures of very neutron-deficient heavy nuclei. The present contribution focuses on the light Pb region where the new data extend the systematics of shape-coexisting yrast states towards the proton dripline. Similarities between band structures and their relation to possible multi-particle multi-hole intruder excitations will be discussed.

Heavy 65-70Co, 68-74Ni, 70-76Cu and 74-81Ga isotopes were produced at the LISOL facility by means of 30 MeV proton-induced fission of 238U. Production rates were deduced and compared to two types of cross-section calculations: the empirical model (V. Rubchenya, private communication) and the PROFI code. Comparison with experimental data favors the latter model. Yields using different beam-target combinations and different energies are calculated and discussed.

Alpha-decay properties of the neutron-deficient isotope 185Pb were studied at the PSB-ISOLDE (CERN) on-line mass separator using the resonance ionisation laser ion source (RILIS). The nuclei of interest were produced in a 1.4 GeV proton-induced spallation reaction of a uranium graphite target. In contrast to previous studies, two α-decaying isomeric states were identified in 185Pb. The relative production of the isomers, monitored by their α-counting rates, could be significantly changed when a narrow-bandwidth laser at the RILIS setup was used to scan through the atomic hyperfine structure. Based on the atomic hyperfine structure measurements, along with the systematics for heavier odd-mass lead isotopes, the spin and the parity of these states were interpreted as 3/2- and 13/2+ and their nuclear magnetic moments were deduced. The α-decay energy and half-life value for the I π = 13/2+ isomer are E α = 6408(5) keV, T 1/2 = 4.3(2) s, respectively; while for the I π = 3/2- isomer ( T 1/2 = 6.3(4) s) two α-decays with E α1 = 6288(5) keV, I α1 = 56(2)% and E α2 = 6486(5) keV, I α2 = 44(2)% were observed. By observing prompt α-γ coincidences new information on the low-lying states in the daughter isotope 181Hg was obtained.

The recoil-tagging technique has been employed to perform an in-beam gamma-ray spectroscopic study of the transfermium nucleus 254No. The experiment was carried out at the Department of Physics of the University of Jyvaskyla and utilised the JUROGAM array of germanium detectors coupled to the gasfilled recoil separator RITU. The ground-state rotational band was extended and evidence for non-yrast states was observed for the first time.

This Brief Report reports on the first observation of the β--delayed γ decay of 215Pb, feeding states in 215Bi. The 215Pb beam was produced using resonant laser ionization and mass separated at the ISOLDE-CERN on-line mass separator. This ensured clean identification of the γ rays as belonging to the decay of 215Pb or its β-decay daughters. A half-life of 147(12) s was measured for the 215Pb β decay and a level scheme for the daughter nucleus 215Bi is proposed, resulting in an extended systematics of the excited states of the neutron-rich Bi isotopes.

The $ \beta^{{+}}_{}$ /EC decay of 185Tl was studied at the ISOLDE facility, the $ \gamma$ -rays belonging to 185Hg have been identified and a partial low-spin level scheme of 185Hg has been built. The decay of 185m+gHg was studied at the ISOCELE facility. Conversion electron lines of very low-energy transitions were observed for the first time. Electron data have been obtained for four transitions in 185Au and two transitions in 185Hg . From the analysis performed using an internal energy calibration procedure the energy location of the 185mHg has been determined to be $ E_{IS}= 103.7(4)$ keV. This $ E_{IS}$ value is consistent with that determined independently, $ E_{IS}=94(13)$ keV, using 185m+gHg $ \alpha$ -decay data from literature. New $ \alpha$ particles emitted from 189m+gPb have been detected and their origins determined by in-source laser spectroscopy at the ISOLDE facility. $ \alpha$ - $ \gamma$ coincidence results have served to locate the $ 13/2^{+}$ isomeric state of 189Pb at $ E_{IS}=40(4)$ keV. This latter $ E_{IS}$ value added to $ \alpha$ -decay data from literature have allowed the energy location of the $ 13/2^{+}$ isomeric states of 193Po and 197Rn at 95(7)keV and 194(12)keV, respectively. The nuclear structure of the isomeric and ground states in the nuclei of the three $ \alpha$ -emitter chains starting with 195m+g, 197m+g, 199m+gRn are discussed.

For the first time, excited states in {sup 185}Pb have been observed in in-beam {gamma}-ray spectroscopic measurements using the recoil-decay tagging method. The resulting level scheme reveals a strongly coupled yrast band structure that originates from coupling of the i{sub 13/2} quasineutron to a prolate deformed core. The band is also observed to de-excite via the spherical {alpha}-decaying 13/2{sup +}isomeric state.

A {beta}-decay study of {sup 77}Cu has been performed at the ISOLDE mass separator with the aim to deduce its {beta}-decay properties and to obtain spectroscopic information on {sup 77}Zn. Neutron-rich copper isotopes were produced by means of proton- or neutron-induced fission reactions on {sup 238}U. After the production, {sup 77}Cu was selectively laser ionized, mass separated, and sent to different detection systems where {beta}-{gamma} and {beta}-n coincidence data were collected. We report on the deduced half-live, decay scheme, and possible spin assignment of {sup 77}Cu.

Objective Hypothermic machine perfusion (HMP) is superior to simple cold storage for kidney preservation. We previous observed in a porcine liver transplantation model increased tumor necrosis factor–α (TNF-α) production eventually leading to poor recipient survival after HMP using standard kidney perfusion solution (KPS-1) compared with simple cold storage. We compared two solutions for HMP preservation of the liver: enriched KPS-1 (EKPS-1) and Aqix RS-I. Methods Pig livers were obtained after cold flushing with histidine-tryptophan-ketoglutarate solution. Subsequently, the livers were subjected to dual-vessel perfusion with two preservation solutions: EKPS-1 (n = 6) and Aqix RS-I (n = 3). After HMP preservation and transplantation, graft and recipient survival, hepatocellular damage (aspartate aminotransferase concentration), TNF-α production, and endothelial cell damage (hyaluronic acid clearance) were recorded. Results No primary graft nonfunction was observed. Recipient survival at postoperative day 3 was similar in both groups (33%). Aspartate aminotransferase concentration measured in serum samples after reperfusion was similar in both groups. After reperfusion, TNF-α concentration was higher and hyaluronic acid clearance was lower in the EKPS-1 group vs the Aqix RS-I group at 60, 120, and 180 minutes (all P Conclusion Hypothermic machine perfusion provided adequate longer term graft survival. After reperfusion, TNF-α production seems to be reduced, and endothelial cell dysfunction remains pronounced with Aqix RS-1 solution compared with EKPS-1 solution.

Isotope shifts and hyperfine splitting parameters have been measured for the neutron-deficient odd-mass lead isotopes 183–189Pb. The measurement was performed at the ISOLDE (CERN) online mass separator using the in-source resonance ionization spectroscopy technique. The nuclear root mean square charge radii and the electromagnetic moments μ and Q_S have been deduced. They follow the smooth trend of the heavier isotopes and indicate the absence of deformation. ispartof: European Physical Journal A, Hadrons and Nuclei vol:41 issue:3 pages:315-321 status: published

For the first time, excitated states in very neutron‐deficient odd‐mass nucleus 185Pb have been observed in an in‐beam γ‐ray measurement. The present data provide evidence for a strong‐coupling of an odd‐neutron hole to the even‐mass prolate core in the light Pb isotopes.

Excited states in the highly neutron deficient odd-odd nucleus Ir-170 have been investigated. The experiment was performed using the Sn-112(Ni-60, pn)Ir-170 reaction and employing the recoil-decay ...

Gamma rays populating the alpha-decaying isomeric state in Ir-169 have been observed for the first time. The experiment employed the recoil-decay tagging method using the JUROGAM gamma-ray spectrom ...

The shape of exotic even-mass (182-190)Pb isotopes was probed by measurement of optical isotope shifts providing mean square charge radii (delta(r(2))). The experiment was carried out at the isolde (cern) on-line mass separator, using in-source laser spectroscopy. Small deviations from the spherical droplet model are observed, but when compared to model calculations, those are explained by high sensitivity of delta(r(2)) to beyond mean-field correlations and small admixtures of intruder configurations in the ground state. The data support the predominantly spherical shape of the ground state of the proton-magic Z=82 lead isotopes near neutron midshell (N=104).

The {beta}-decay properties of {sub 28}{sup 72}Ni{sub 44} and {sub 29}{sup 72}Cu{sub 43} have been studied at the LISOL facility of Louvain-La-Neuve and at the CERN-ISOLDE facility, respectively. These neutron-rich nuclei have been produced in the proton-induced fission of {sup 238}U. Their decay schemes are presented and the lifetime T{sub 1/2}=6.63(3) s of {sup 72}Cu was measured. No {beta}-decaying isomeric state was found in {sup 72}Cu, in line with a suggested spin (2) for its ground state. Spin and parity assignments of the observed excited states in the odd-odd nucleus {sup 72}Cu are proposed and discussed in terms of coupling between the valence proton and neutrons. Comparison is made with a schematic shell-model picture of {sup 72}Cu and with large-scale shell-model calculations performed in the (2p{sub 3/2}1f{sub 5/2}2p{sub 1/2}1g{sub 9/2}) shell space outside the doubly magic {sub 28}{sup 56}Ni{sub 28} core.

The yrast states in the light platinum isotopes Pt169-173 have been investigated in a recoil-decay tagging experiment using the JUROGAM gamma-ray spectrometer in conjunction with the RITU gas-filled recoil separator and the GREAT tagging spectrometer. Gamma-ray transitions have been established for the first time in the odd-N isotopes, Pt-169 and Pt-173, and the yrast sequences in Pt-170 and Pt-172 have been extended. We discuss the possibility that the weakly deformed yrast structures of Pt-170, Pt-172, and Pt-173 are crossed by a deformed intruder configuration at spin similar to 8h.

Evidence for the presence of non‐yrast states in 254No has been observed in two different in‐beam experiments carried out at the University of Jyvaskyla. Firstly an in‐beam conversion electron spectroscopic study was performed with the SACRED spectrometer, revealing a distribution consisting of high‐multiplicity electron cascades. This provides an indirect proof of the presence of high K‐bands in 254No. In a more recent in‐beam γ‐ray spectroscopic measurement, evidence for the decay of non‐yrast states in 254No has been observed for the first time. It is speculated that the observation of high‐energy γ rays is due to the decay of a K = 3 band‐head state.

The production of the very neutron-deficient nuclides $^{184\ensuremath{-}192}\mathrm{Bi}$ and $^{186\ensuremath{-}192}\mathrm{Po}$ in the vicinity of the neutron midshell at N = 104 has been studied by using heavy-ion-induced complete fusion reactions in a series of experiments at the velocity filter SHIP. The cross sections for the xn and pxn evaporation channels of the $^{46}\mathrm{Ti}$+$^{144}\mathrm{Sm}$$\ensuremath{\rightarrow}^{190}\mathrm{Po}{}^{*},$$^{98}\mathrm{Mo}$+$^{92}\mathrm{Mo}$$\ensuremath{\rightarrow}^{190}\mathrm{Po}{}^{*},$$^{50,52}\mathrm{Cr}$+$^{142}\mathrm{Nd}$$\ensuremath{\rightarrow}^{192,194}\mathrm{Po}{}^{*}$, and $^{94,95}\mathrm{Mo}$+$^{93}\mathrm{Nb}$$\ensuremath{\rightarrow}^{187,188}\mathrm{Bi}{}^{*}$ reactions were measured. The results obtained, together with the previously known cross section data for the heavier Bi and Po nuclides, are compared with the results of statistical model calculations carried out with the HIVAP code. It is shown that a satisfactory description of the experimental data requires a significant (up to 35%) reduction of the theoretical fission barriers. The optimal reactions for production of the lightest Bi and Po isotopes are discussed.

A \ensuremath{\beta}-decay study of the even mass $^{74,76,78}\mathrm{Cu}$ isotopes toward levels in $^{74,76,78}\mathrm{Zn}$ was performed at the ISOLDE mass separator. The copper isotopes were produced in proton- or neutron-induced fission reactions on $^{238}\mathrm{U}$, laser ionized, mass separated, and sent to a $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ detection system. Half-lives, decay schemes, and possible spin configurations were obtained for the copper isotopes. The results are compared with calculations using schematic forces as well as large-scale shell-model calculations with realistic forces.

NESTER; International audience; The neutron-rich nuclei $^{72}$Ni and $^{72}$Cu have been produced in the proton-induced fission of $^{238}$U at the LISOL and ISOLDE facilities of Louvain-La-Neuve and CERN. Partial beta-decay schemes are presented, giving some information about the nuclear structure of their daughter nuclei $^{72}$Cu and $^{72}$Zn. The lifetime of $^{72}$Cu was determined to be $T_1/2$ = 6.63(3) s, in line with previous measurements. No $\beta$-decaying isomeric states were identified in $^{72}$Cu, in contrast to $^{70}$Cu. The spin and the parity of several states in $^{72}$Cu are tentatively assigned and a comparison is made with different shell-model predictions.

Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations.

The 70Ni nucleus has been produced at the LISOL facility and its beta decay to 70Cu has been observed. In parallel, the 70Cu nucleus has been produced at the ISOLDE facility. A new third beta-decaying isomeric state in 70Cu has been identified, partly with the aid of the in-source laser spectroscopy method. Its measured half-life is T1/2=33(2) s. In addition, two isomeric transitions in 70Cu have been observed at energies of 101.1(3) and 141.3(3) keV, and it allowed the relative placement of the three 70Cu isomeric states and their tentative spin and parity assignments. The new 70Cu isomer was found to be weakly populated in the beta decay of 70Ni. It allowed the construction of the 70Ni decay scheme. Furthermore, the beta decay of the three 70Cu isomers to 70Zn has been measured and their decay schemes are presented. The 70Ni beta decay to the isomeric states in 70Cu and their subsequent isomeric decay and beta decay to 70Zn are discussed within the extreme shell-model picture of two valence nucleons outside the semidouble magic 2868Ni40 core and it yields satisfactory results. Large-basis shell-model calculations using 2856Ni28 as the core and a realistic effective interaction support rather well the suggested interpretation. (Less)

A simple model to calculate alpha-decay Hindrance Factors is presented. Using deformation values obtained from PES calculations as the only input, Hindrance Factors for the alpha-decay of Rn- and Po-isotopes are calculated. It is found that the intrinsic structure around the Fermi surface determined by the deformed mean field plays an important role in determining the hindrance of alpha-decay. The fair agreement between experimental and theoretical Hindrance Factors suggest that the wave function obtained from the energy minima of the PES calculations contains an important part of the correlations that play a role for the alpha-decay. The calculated HF that emerges from these calculations render a different interpretation than the commonly assumed n-particle n-hole picture., Comment: 7 pages, 9 figures

In-beam γ-ray spectroscopy measurements provide important information on coexisting normal and intruder configurations in lead nuclei. However, in these experiments the yrast states are preferentially populated so that in many cases nothing is known about non-yrast states that are essential for obtaining a fuller understanding. Complementary experiments designed to study fine structure in the a decays of polonium nuclei have led to the discovery of low-spin non-yrast states in the daughter lead nuclei, while higher-spin states can be identified through the γ decays of isomeric states. The α-decay studies have the additional benefit of allowing information on configuration mixing in the polonium parents to be deduced from the measured hindrance factors.

The neutron-rich Tl, Pb and Bi isotopes are of exceptional interest to trace the evolution of single-particle levels away from the doubly magic 208Pb towards the neutron-rich side of the nuclear chart. While 208Pb is well understood in terms of the shell model, experimental data on the heavier isotopes is very scarce and it is far from clear to what extent the shell model is upheld [1]. Furthermore, large branchings ratios for β-delayed neutron emission are expected in this mass region, adding astrophysical interest to the subject [2].

Nuclides in the vicinity of the doubly magic 78Ni nucleus are ideal test cases for the nuclear shell model [1,2]. Still, experimental data in this region is rather scarce because of experimental limitations. In this contribution we report the first observation of the β-decay of 78Cu, only one proton and one neutron hole away from 78Ni.

Prompt gamma rays have been observed for the first time from the neutron-deficient nucleus Po-191 using the recoil-decay tagging technique at the RITU gas-filled separator. In addition improved alp ...