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To control the authenticity of an old wine without opening the bottle, we developed a few years ago a method based on the measurement of the 137 Cs activity. However, for recent vintages, the 137 Cs activity drops to far too low values (most of the time less than 10 mBq/L for a 10-year-old wine) for this method to perform correctly. In this paper we examine the possibility to date wines using the natural radio-element 210 Pb which has a 22-year period. This new method we propose implies the opening of the bottle and the follow-on destruction of the wine itself, which means that it can only be used for investigating non-expensive bottles or wine lots where there are multiple bottles of the same provenance. Uncertainties on the resulting 210 Pb radioactivity values are large, up to more than 50%, mainly due to local atmospheric variations, which prevents us to carry out precise dating. However it can be used to discriminate between an old wine (pre-1952) and a young wine (past-1990), an information that cannot be obtained with the other techniques based on other isotopes ( 137 Cs, 14 C or tritium).

Neutron capture cross sections of 232T/i have been measured relative to 197Au in the energy region from 30 keV to 600 keV. The neutron source was the reaction 7Li(p, n) produced on the 4 MV Van de Graaff Accelerator of the Centre d' Etudes Nucléaires de Bordeaux (CENBG). Preliminary analysis of the measurements indicates that the cross sections are closer to the JENDL database values.

Lead-210 is unknown to the general public, but one of its daughters, polonium-210, made newspaper headlines several times in 2006 and 2012. In 2006 the whole world learned that a former Russian KGB agent named Alexander Litvinenko had been poisoned by polonium-210, a powerful short-lived alpha emitter. The ingested poisoning activity was estimated to be more than 1–3 GBq [1], which is ~6 μg of pure 210Po. The experts agree that it is an ideal weapon, impossible to detect with the naked eye and that a lethal dose can be held in a volume the size of a homeopathic pill. In 2012 we learned that traces of 210Po were found on the underwear, hat, and toothbrush of Yasser Arafat, the Palestinian leader who died in 2004. Calculation of the activity at the time of his death shows that poisoning with 210Po is not excluded. The different samples collected during the exhumation will probably answer the question.

Following the Fukushima nuclear accident, low-background gamma spectrometry measurements were performed with HPGe detectors at the PRISNA platform located at the CENBG laboratory in Bordeaux, France. Different kinds of samples were collected and measured between March 26 and May 14, 2011. The first fission product observed was (131)I with maximum activity values of 2.4 mBq/m(3) in atmospheric dusts in air, 3.5 Bq/L in rain water, 15 Bq/kg in grass and 0.9 Bq/L in cow milk. The (134,137)Cs isotopes were also detected in air and in grass at a maximum level of 0.2 mBq/m(3) and 0.7 Bq/kg respectively, around one order of magnitude less than (131)I activity, but they were below detection limits in the other samples. All these activity values were consistent with others measured in France by IRSN and were well below those reported in May 1986 after the Chernobyl accident.

In a series of experiments at the SISSI/LISE3 facility of GANIL conducted between 1999 and 2004, we have collected decay information for proton-rich nuclei between {sup 36}Ca and {sup 56}Zn. The data allowed us to study the decay properties of 26 nuclei. The main experimental information obtained for all nuclei is their {beta}-decay half-life and their total {beta}-delayed proton emission branching ratio. For many nuclei, individual proton groups and {gamma} rays were identified and allowed us to establish first partial decay schemes for some of the nuclei studied. In addition, mass-excess values have been determined for some of the nuclei by means of the isobaric multiplet mass equation. For {sup 50}Ni, the decay via {beta}-delayed two-proton emission could be tentatively identified. The decay of {sup 49}Ni allowed for the first time to identify the first 2{sup +} state in {sup 48}Fe. The experimental data are confronted to model predictions for the half-life and the mass-excess values.

PACS conv.GSI; The isotopic distributions and recoil velocities of the fission fragments produced in the spallation reaction 208Pb + p at 500 A MeV have been measured using the inverse-kinematics technique, a lead beam onto a liquid-hydrogen target, and the high-resolution spectrometer FRS at GSI. The shapes of the different distributions are found in good agreement with previously published data while the deduced total fission cross-section is higher than expected from existing systematics and some previous measurements. From the experimental data, the characteristics of the average fissioning system can be reconstructed in charge, mass and excitation energy, and the average number of post-fission neutrons can be inferred. The results are also compared to different models describing the spallation reaction. The intranuclear cascade code INCL4 followed by the de-excitation code ABLA is shown to describe reasonably well the evolution of the isotopic distribution shapes between 500 and 1000 A MeV.

A systematic investigation of the isotopic cross sections of nuclear residues produced in the reactions238U (1 A GeV)+p,d has been performed with the high-resolution magnetic spectrometer FRS at GSI. The large range of excitation energies induced in these reactions, together with the high fissility of uranium-like systems constitute an optimum scenario to study the dynamics of spallation reactions. In particular, some fundamental questions connected to the role of dissipation and the onset of a break-up stage at high temperatures can be addressed with these data.

The production of heavy nuclides from the spallation-evaporation reaction of 238U induced by 1 GeV protons was studied in inverse kinematics. The evaporation residues from tungsten to uranium were identified in-flight in mass and atomic number. Their production cross-sections and their momentum distributions were determined. The data are compared with empirical systematics. A comparison with previous results from the spallation of 208Pb and 197Au reveals the strong influence of fission in the spallation of 238U.

In an experiment at the SISSI-LISE3 facility of GANIL, the decay of the proton drip-line nucleus Fe45 has been studied after projectile fragmentation of a Ni58 primary beam at 75 MeV/nucleon impinging on a natural nickel target. Fragment-implantation events have been correlated with radioactive decay events in a 16x16 pixel silicon strip detector on an event-by-event basis. The decay-energy spectrum of Fe45 implants shows a distinct peak at (1.06+/-0.04)MeV with a half-life of T1/2 = (4.7+3.4-1.4)ms. None of the events in this peak is in coincidence with beta particles which were searched for in a detector next to the implantation detector. For a longer correlation interval, daughter decays of the two-proton daughter Cr43 can be observed after Fe45 implantation. The decay energy for Fe45 agrees nicely with several theoretical predictions for two-proton emission. Barrier-penetration calculations slightly favour a di-proton emission picture over an emission of two individual protons and point thus to a He2 emission mode.

The production cross sections and the kinematical properties of primary residual nuclei have been studied in the reaction 208 Pb(1 A GeV)+d. Isotopic distributions were measured for all elements from titanium ( Z =22) to lead ( Z =82). The measured kinematical properties of the residues were also used to disentangle the relevant reaction mechanisms, spallation–evaporation and spallation–fission. The fragment separator FRS at GSI, Darmstadt, was used to separate and identify the reaction products. The measured quantities are important for the design and planning of future radioactive-beam facilities and accelerator-driven systems. The measured data of the present work are comprehensively compared with the experimental data from the reaction 208 Pb(1 A GeV)+p.

A large experimental program has been initiated at GSI to determine the production cross sections of heavy residues in relativistic heavy-ion collisions. The complete isotopic distributions of spallation–evaporation residues of the reactions induced by 1 GeV protons and 2 GeV deuterons in 238U are presented. The primary reaction products were fully identified in mass and atomic number prior to beta decay by using the fragment separator FRS. These data provide basic information to estimate the intensities of radioactive nuclear beams to become available in future RNB facilities using isotope separation on-line (ISOL) or in-flight separation techniques.

With the inverse kinematics method, the reaction mechanism which leads to the formation of light nuclides was investigated with a 1 A GeV 238 U beam impinging on a liquid H 2 target. Isotopes of all elements with Z ⩾6 were unambiguously identified, and the velocity of every produced nuclide was measured with great precision. Results show that very asymmetric fission of uranium nuclei produces neutron-rich isotopes of elements down to around charge 10. When uranium interacts with heavier nuclei the features of the reaction change drastically: while fission is the main mechanism for the production of light masses in 1 A GeV 238 U on H 2 , projectile fragmentation plays a dominant role in 1 A GeV 238 U on Ti leading to the formation of stable or neutron-deficient isotopes of all elements.

The production of primary residual nuclei in the reaction 1 A GeV 208Pb on proton has been studied by measuring isotopic distributions for all elements from titanium (Z=22) to lead (Z=82). Kinematical properties of the residues were also determined and used to disentangle the relevant reaction mechanisms, spallation (projectile fragmentation) and fission. The fragment separator FRS at GSI, Darmstadt, was used to separate and identify the reaction products. The measured production cross sections are highly relevant for the design of accelerator-driven subcritical reactors and for the planning of future radioactive-beam facilities.

Spallation residues produced in 1 GeV per nucleon ${}^{208}\mathrm{Pb}$ on proton reactions have been studied using the Fragment Separator facility at GSI. Isotopic production cross sections of elements from ${}_{61}\mathrm{Pm}$ to ${}_{82}\mathrm{Pb}$ have been measured down to 0.1 mb with a high accuracy. The recoil kinetic energies of the produced fragments were also determined. The obtained cross sections agree with most of the few existing gamma-spectroscopic data. The data are compared with different intranuclear-cascade and evaporation-fission models. Drastic deviations were found for a standard code used in technical applications.

The very neutron deficient $Z\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}N+1$ nuclei ${}_{39}^{77}\mathrm{Y}$, ${}_{40}^{79}\mathrm{Zr}$, and ${}_{42}^{83}\mathrm{Mo}$ have been observed for the first time following the fragmentation of a ${}^{92}\mathrm{Mo}$ beam. In contrast, no evidence was found for the existence of ${}_{41}^{81}\mathrm{Nb}$ and ${}_{43}^{85}\mathrm{Tc}$. The observation of ${}_{39}^{77}\mathrm{Y}$ is of particular interest in light of the instability of the odd-proton, $Z\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}N+1$ systems, ${}_{35}^{69}\mathrm{Br}$, ${}_{37}^{73}\mathrm{Rb}$, ${}_{41}^{81}\mathrm{Nb}$, and ${}_{43}^{85}\mathrm{Tc}$, and may be explained as a consequence of the shape polarizing effect of the highly deformed, prolate $Z\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}N\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}38$ core. The experimental results are discussed within the framework of the shell-correction model, which together with proton-decay calculations allow an estimate of the proton separation energies of these highly exotic systems to be calculated.

Two new isomeric states in the self-conjugate nucleus 66As have been observed at the final focus of the LISE3 spectrometer at GANIL. The nucleus has been produced in a fragmentation reaction of 78Kr at 73A MeV. The 66m1,m2As isomeric levels are placed at excitation energies of E ∗m1 =3023.9 keV and E ∗m2 =1356.7 keV. Half-lives of T1/2m1=17.5(15) μs and T1/2m2=1.9(5) μs have been measured for the isomers and a decay scheme has been established.

In an experiment at the LISE3 facility of GANIL, we used the projectile fragmentation of a 36 Ar primary beam at 95 MeV/nucleon to produce the isotope 24 Si. The beta decay half-life of 24 Si has been determined to be T 1/2 = (140 ± 8) ms, in agreement with earlier measurements. In addition to the decay of the isobaric analog state, several proton peaks are observed for the first time allowing to identify most of the Gamow-Teller transitions to unbound states and to present a partial decay scheme for 24 Si. These results are compared with shell-model predictions.

23Si isotopes have been produced as projectile fragments of a 36Ar primary beam at 95 MeV/nucleon at the LISE3 spectrometer of GANIL. After implantation in a detector telescope, β-delayed one-proton and β-delayed two-proton emission has been observed. The main one-proton peaks are at (1.32±0.04)MeV, (2.40±0.04)MeV, and (2.83±0.06)MeV. The total decay energy for the β2p decay is (6.18±0.10)MeV for the decay to the ground state and (5.86±0.10)MeV for the decay to the first excited state in the daughter nucleus. However, energetically possible decays via βpα and β3p emission have not been identified. The spectra allowed us to determine the excitation energy of the isobaric analogue state in 23Al. This enabled us to calculate the coefficients of the T = 5/2 isobaric multiplet mass equation for A = 23. The mass excess of the 23Si ground state was deduced. This value is compared to different theoretical predictions. Additionally, we determined the branching ratios for the different decay branches. A half-life measurement yielded T1/2 = (40.7±0.4)ms.

In an experiment at the LISE3 facility of GANIL, we produced the proton-rich isotope 22Al by the fragmentation of a 36Ar primary beam at 95 MeV/nucleon. After implantation in a detector telescope, the decay of 22Al via β-delayed proton emission, β-delayed two-proton emission as well as, for the first time, via β-delayed α emission has been studied. An α peak has been observed at (3.27 ± 0.04) MeV with a branching ratio of (0.31 ± 0.09) %. The comparison of the different decay channels to those of the mirror nucleus 22F and to shell-model calculations favor a 3+ state as being the ground state of 22Al. A half life of T1/2 = (59 ± 3) ms has been measured.

A primary beam of ${}^{58}$Ni at 600 MeV/nucleon from the SIS synchrotron at GSI was used to produce proton-rich isotopes in the titanium-to-nickel region by projectile fragmention on a beryllium target. The fragments were separated by a projectile-fragement separator and unambiguously identified. We report here the first observation of the ${T}_{z}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}7/2$ nuclei ${}^{45}$Fe and ${}^{49}$Ni, the most proton-rich nuclei ever synthesized with an excess of seven protons. In addition, the new isotope ${}^{42}$Cr $({T}_{z}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}3)$ was identified. According to commonly used mass predictions, these isotopes are all unbound with respect to two-proton emission from their ground states. From the nonobservation of ${}^{38}$Ti $({T}_{z}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}3)$ in this experiment, an upper limit of 120 ns is deduced for the half-life of this isotope.

The proton-rich nuclei 44Cr, 47Mn, 48,49Fe and 50Co have been produced by fragmentation of a 58Ni beam at 650 MeV/u. The isotopic separation of these nuclei has been achieved with the GSI Projectile-Fragment Separator FRS. The isotopes have been identified in flight by ΔE-ToF-Bϱ measurements. After implantation in a stack of seven silicon detectors, the signals measured for implantation and radioactive decay were unambiguously correlated in time due to low counting rates. On the basis of the two proton peaks observed for 50Co at (2034±30) keV and (2740±41) keV with a half-life of (44±4) ms, a partial decay scheme is proposed for this nucleus. A single proton peak at (959±33) keV was observed for 48Fe with a half-life of (44±7) ms. This emission is attributed to the decay of the T = 2 isobaric analog state in 48Mn. No deviation from the quadratic form of the isobaric multiplet mass equation is observed. Additional information on β-delayed proton branches of 49Fe, 44Cr and 47Mn was also obtained.

In an experiment at the SISSI/LISE facility of GANIL, we used the projectile fragmentation of a ${}^{78}\mathrm{Kr}$ primary beam at 73 MeV/nucleon to produce new isotopes of astrophysical interest. We obtained clear evidence for the existence of the five new isotopes ${}^{60}\mathrm{Ga}$, ${}^{64}\mathrm{As}$, ${}^{69,70}\mathrm{Kr}$, and ${}^{74}\mathrm{Sr}$. However, we did not find any evidence for ${}^{69}\mathrm{Br}$, whereas comparable nuclei were observed with more than 1000 counts. The isotope ${}^{69}\mathrm{Br}$ is thus deduced to be a proton-unbound nucleus with a half-life shorter than about 100 ns. The influence of these results on our understanding of the astrophysical RP process is discussed.

At the projectile-fragment separator FRS of GSI, relativistic secondary beams of about 520 MeV/nucleon were produced by fragmentation of a primary beam of58Ni at 650 MeV/nucleon in a beryllium target. By means of aΔE—Bρ—TOF measurement, the fragments have been identified and their charge-changing probabilities in targets of CH2, C, Al, and Pb have been determined. We describe the results for the total charge-changing cross sections in this first paper, whereas a second article deals with the partial charge-changing cross sections. At the drip line, the measured charge-changing cross sections exhaust close to 100% of the total interaction cross sections as calculated with semiempirical models. The measurements at the proton drip line with low-Z targets indicate that only a very small increase of the cross sections may be observed, whereas the measurements with a lead target show that no significant increase of the total charge-changing cross sections is present which would be a hint for low-lying dipole strength. Our experimental data are compared to Glauber-type calculations.

Total nuclear charge-changing cross sections σΔz in a CH2 target were measured for 54 isotopically identified secondary beams around A = 60 produced from a 1A·GeV86Kr beam via projectile fragmentation. With secondary beams between T z = 1 2 and −3, the isospin dependence of σΔz was investigated systematically. Contrary to the predictions of so-called overlap formulae, the σΔz values are not a function of the projectile mass alone, but are found to depend on the projectile isospin. A comparison of the data with the predictions of the statistical abrasion model reveals that this behaviour can be understood by the combined influence of the abrasion and the ablation phase in relativistic heavy-ion collisions. On the basis of this improved understanding, previous findings of anomalously large cross sections of secondary-reaction products are discussed.

Using a primary beam of $^{58}\mathrm{Ni}$ at 650 MeV/nucleon impinging on a beryllium target, production cross sections of proton-rich fragments from projectile fragmentation have been measured at the projectile-fragment separator FRS at Gesellschaft f\"ur Schwerionenforschung Darmstadt m.b.H. The experimental data ranging from nickel to scandium for isotopes close to stability as well as for fragments at the proton drip line are compared to predictions of the microscopic ISApace code, to calculations with a revised abrasion-ablation model and with the statistical abrasion model, and to the results of the empirical parametrization EPAX. Besides these systematic measurements, evidence for the particle stability of $^{50}\mathrm{Ni}$ has been found for the first time, whereas the nuclei $^{49}\mathrm{Co}$ and $^{54}\mathrm{Cu}$ are shown to be unbound. These observations are compared to mass predictions.

The isotope [sup 52]Ni has been produced by fragmentation of a [sup 58]Ni beam at 68 MeV/nucleon on a nickel target and separated using the LISE spectrometer at GANIL. We have measured the half-life of [sup 52]Ni and the energies of [beta]-delayed protons emitted during the decay. Two proton lines have been observed at [ital E][sub [ital p]]=1.06[plus minus]0.05 MeV and 1.34[plus minus]0.06 MeV with branching ratios of 0.06[plus minus]0.01 and 0.11[plus minus]0.01, respectively. The measured half-life of [sup 52]Ni is [ital T][sub 1/2]=38[plus minus]5 ms. A partial decay scheme is proposed.

Two aspects of heavy ion channeling are presented. The first aspect is related to the fact that channeled ions interact only with the most loosely bound target electrons. One can take benefit of this feature to study processes such as radiative electron capture (REC) and resonant transfer and excitation (RTE) in a dense quasi-free electron gas. The experimental work, performed at GANIL, devoted to these two processes is described. A possible extension to Nuclear RTE or NEEC (nuclear excitation by electron capture) studies is also described. The second aspect discussed is related to the periodicity of the potential experienced by channeled ions. We show that in a well chosen case this could lead to a significant and detectable coherent excitation of the projectile nucleus.

The principle of a new setup for the decay spectroscopy of proton-rich nuclei is described. In the method proposed, nuclei produced in projectile fragmentation are implanted in a gas detector and deposited by electrostatic collection at the surface of a second detector, i.e. at the interface of two detectors. A microstrip-anode gas counter has been developed to test this technique with 20 Na and 21 Mg secondary beams. Collection rates have been measured using their known β - α and β-p branching ratios, and particle identification has been performed. These results allow to directly compare the performance of such a detector design to that of a standard silicon-detector telescope. The experimental results are supported by Monte Carlo simulations.

At the fragment separator FRS at GSI, relativistic secondary beams with nuclear mass numbers 50 ⩽ A ⩽ 62 were produced by the fragmentation of a 1 A ⊙ ot GeV 86 Kr beam in a 9 Be production target. The nuclear charge and mass numbers of the secondary-beam particles were determined by a Δ −t.o.f− Bϱ measurement. The fragmentation of stable and neutron-deficient manganese, iron, cobalt and nickel isotopes in a composite carbon-hydrogen target, placed behind the separator, was investigated. The element distributions of the secondary-fragmentation products were found to depend strongly on the neutron-to-proton ratio of the projectile. Calculations with a statistical abrasion model allow an explanation of the observed features by means of the different influences of the neutron-to-proton ratio of the projectile on the abrasion and ablation steps of the fragmentation r reaction.

The different {beta}-delayed particle-decay modes of {sup 31}Ar are investigated by means of a new silicon-detector telescope. Identification of {beta}-delayed two-proton decay, and {beta}-delayed three-proton decay observed for the first time, is made possible by Monte Carlo simulations of the detector response. Other {beta}-delayed single-proton branches are also investigated, and none of the energetically allowed {beta}-{alpha} and {beta}-{ital p}{alpha} decay modes are found. Finally, the results of this experiment are compared to shell-model calculations.

For many years the neutrino group in the CENBG has been involved in the development of low background γ -ray spectrometers, based on the use of HPGe crystals. When applied to radioactivity measurements of wine in bottles, it has been shown that besides the well-known isotope 40 K, the wine contains also trace amounts of 137 Cs (less than 1 Bq/l) with an activity depending on the vintage. This technique has thus led to the possibility to date the wine bottles of vintages between 1952 and ∼1980 and to verify the year written on the label or on the cork. Since the measurements do not require opening the bottle, the technique has also proved to be very useful for detecting counterfeit wines of the XIXth century and first half of the XXth century. To cite this article: Ph. Hubert et al., C. R. Physique 10 (2009).

Using the magnetic spectrometer SPES I at SATURNE, energy-loss measurements have been performed for projectiles of 40 Ar (401 MeV/u), 36 P (362 MeV/u), 15 N (149 MeV/u), 11 Li (131 MeV/u) and 8 Li, 9 Li (130 MeV/u) in carbon, aluminum and lead targets. The experimental results are compared to calculations based on a modified relativistic Bethe formula and to a semiempirical formula using a Z 2 scaling law for the stopping power and an effective charge parametrization for the heavy ions.

Fission fragments of 1A GeV{sup 238}U nuclei interacting with a deuterium target have been investigated with the Fragment Separator (FRS) at Gesellschaft fuer Schwerionenforschung (GSI) by measuring their isotopic production cross sections and velocities. Results, along with those obtained recently for spallation-evaporation fragments, provide a comprehensive analysis of the spallation nuclear productions in this reaction. Details about the experimental performance, data reduction and results are presented.

Isotopic production cross sections and momentum distributions of 602 residual nuclei produced in the collision of $^{238}\mathrm{U}$($1A$ GeV) with deuterium have been measured. These data are relevant for a better understanding of spallation reactions for use as neutron sources for accelerator-driven systems or to produce radioactive nuclear beams. Access to primary residue production makes it possible to study the main reaction mechanisms involved: intranuclear cascade, particle evaporation, and fission. The characteristics of the reaction investigated and the high fissility of the $^{238}\mathrm{U}$ and the dinucleon projectile system are discussed and compared with other available experimental data.

PACS; International audience; The production of residual nuclei in p + Fe collisions has been measured at GSI on the FRS facility by means of the reverse kinematic techniques at 300, 500, 750, 1000 and 1500 MeV/A. The cross-sections larger than 0.01 mb of all isotopes with Z larger than 8 have been obtained. Velocity distributions were also measured. Comparisons to models describing spallation reactions and some empirical formulae often used in astrophysics are presented. These data are directly used to calculate impurety production and DPAs in a thin window as foreseen in spallation sources or accelerator-driven systems

The still increasing and developing world population demands more energy. Further burning of coal, oil and gas produces still more CO2 deteriorating the climate. Anyhow, oil and gas will run out in the middle of the century. Planning a decent future with a minimum supply of energy for those who will follow us, requires re-examining all possibilities of non-polluting, renewable, and sustainable energies including nuclear options. There are two nuclear reactions which allow for a long-term exploitation: (i) converting H into He by fusion or (ii) converting U and Th into Pu and U to be burnt by fission. In this paper, the fission option is the target. The real long-term reserves of fission energy lie in the even-even isotopes U and Th, as the supplies of U, like fossil fuels, are restricted, as well. The remaining U and available Pu could be burnt in a 3 generation of reactors (EPR) using mixed U/Pu-fuel (MOX). Aiming at a contribution of fission energy to the world electricity production of one third, that is three times more nuclear power than today, reactors of a 4 generation should be envisaged, ready to wide technological applications in the middle of the century. Such an option could be foreseen as an implement of a peaceful future.

Isotopically resolved cross sections and velocity distributions have been measured in charge-pickup reactions of $1A\phantom{\rule{0.3em}{0ex}}\mathrm{GeV}$ $^{208}\mathrm{Pb}$ with proton, deuterium, and titanium targets. The total and partial charge-pickup cross sections in the reactions $^{208}\mathrm{Pb}+^{1}\mathrm{H}$ and $^{208}\mathrm{Pb}+^{2}\mathrm{H}$ are measured to be the same within the limits of the error bars. A weak increase in the total charge-pickup cross section is seen in the reaction of $^{208}\mathrm{Pb}$ with the titanium target. The measured velocity distributions show different contributions---quasielastic scattering and $\ensuremath{\Delta}$-resonance excitation---to the charge-pickup production. Data on total and partial charge-pickup cross sections from these three reactions are compared with other existing data and also with model calculations based on the coupling of different intranuclear cascade codes and an evaporation code.

Leaves of plants have the ability to accumulate the long-lived fission product (99)Tc. In the present work, an attempt was made to separate and characterize technetium species formed in maize grown on soil contaminated with Tc(VII)O(4)(-) solution. Data obtained from selective extraction, a Phosphorimager and liquid scintillation were employed.

Experiment at the GANIL / LISE3 facility; International audience; According to most mass models, several of the best candidates for two‐proton radioactivity lie in the A = 50 mass region, at the proton drip‐line. Recent experiments using the fragmentation of a 58Ni beam allowed us to reach this region and observe some of these candidates, like 45Fe and 48Ni. During an experiment at the GANIL / LISE3 facility helded in 2000, we could identify 22 events of implantation of 45Fe nuclei. The energy distribution of the corresponding decay events shows a clear peak at (1.14 ± 0.04) MeV that could be assigned to the direct 2‐proton emission from the ground state. This energy is in very good agreement with several theoretical predictions, and no coincident β particle has been observed experimentally. A half‐life of (4.7−1.4+3.4) ms has been measured for the decay of 45Fe.

The isotopic production cross sections of heavy residues in relativistic heavy-ion collisions have been investigated in inverse kinematics. The primary reaction products were fully identified in mass and atomic number prior to beta decay using the fragment separator FRS. The huge collection of data obtained helps in the understanding of the two main reaction mechanisms involved: fragmentation and fission. These data provide basic information for future radioactive ion beam facilities and for technical applications like intense neutron sources by means of spallation targets.

In an experiment at the SISSI-LISE3 facility of GANIL, the decay of the proton drip line nucleus $^{\mathrm{45}}\mathrm{F}\mathrm{e}$ has been studied. Fragment-implantation events have been correlated with radioactive decay events in a $16\ifmmode\times\else\texttimes\fi{}16$ pixel silicon-strip detector. The decay-energy spectrum of $^{\mathrm{45}}\mathrm{F}\mathrm{e}$ implants shows a distinct peak at $(1.14\ifmmode\pm\else\textpm\fi{}0.04)\text{ }\text{ }\mathrm{M}\mathrm{e}\mathrm{V}$ with a half-life of ${T}_{1/2}=({4.7}_{\ensuremath{-}1.4}^{+3.4})\text{ }\text{ }\mathrm{m}\mathrm{s}$. None of the events in this peak is in coincidence with $\ensuremath{\beta}$ particles. For a longer correlation interval, daughter decays of the two-proton daughter $^{\mathrm{43}}\mathrm{C}\mathrm{r}$ can be observed after $^{\mathrm{45}}\mathrm{F}\mathrm{e}$ implantation. The decay energy for $^{\mathrm{45}}\mathrm{F}\mathrm{e}$ agrees nicely with several theoretical predictions for two-proton radioactivity.

An experiment was performed at GANIL using a high-intensity 58 Ni beam at 74.5 MeV/nucleon on a nickel target. The projectile fragments produced in the high-acceptance SISSI device were selected in the LISE3 spectrometer using the Wien filter. The detection setup performed an unambiguous identification of four 48 Ni implantation events. A lower limit of its half-life of the order of 0.5 μs and an estimate of the production cross section of about 0.05 pb were deduced. In addition, a few tens of 45 Fe and 49 Ni nuclei were implanted, which may give information on their decay modes. Besides, 48 Ni and 45 Fe are very good candidates for two-proton radioactivity, still to be observed.

The production cross sections and the kinematical properties of primary residual nuclei have been studied in reactions 197Au+p, 208Pb+p,d, 238U+p,d, and 238U+208Pb at energies around 1 A GeV. The measured kinematical properties of the residues were also used to disentangle the relevant reaction mechanisms, spallation-evaporation and spallation-fission. The fragment separator FRS at GSI, Darmstadt, was used to separate and identify the reaction products. The measured quantities are important for the design of accelerator-driven subcritical reactors and for the planning of future radioactive-beam facilities.

In an experiment at the SISSI/LISE3 facility of GANIL, the most proton-rich zinc isotopes 55,56Zn have been observed for the first time. The experiment was performed using a high-intensity 58Ni beam at 74.5 MeV/nucleon impinging on a nickel target. The identification of 55,56Zn opens the way to 54Zn, a good candidate for two-proton radioactivity according to theoretical predictions., 2 pages, 1 figure, accepted for publication in Eur. Phys. J. A

The neutron capture cross section of {sup 232}Th has been measured relative to {sigma}(n, {gamma}) for {sup 197}Au and {sigma}(n,f) for {sup 235}U in the energy range from 60 keV to 2 MeV. Neutrons were produced by the {sup 7}Li(p,n) and T(p,n) reactions at the 4-MV Van de Graaff Accelerator of CEN Bordeaux-Gradignan. The activation technique was used, and the cross section was measured relative to the {sup 197}Au(n,{gamma}) standard cross section up to 1 MeV. The characteristic gamma lines of the product nuclei {sup 233}Pa and {sup 198}Au were measured with a 40% high-purity germanium detector. Above this energy, the reaction {sup 235}U(n,f) was also used as a second standard, and the fission fragments were detected with a photovoltaic cell. The results, after applying the appropriate corrections, indicate that the cross sections are close to the JENDL-3 database values up to 800 keV and over 1.4 MeV. For energies in the intermediate range, our values are slightly lower than those from all the libraries.

\ensuremath{\gamma}-ray decays depopulating isomeric states have been observed in a number of very neutron deficient nuclei around $A\ensuremath{\sim}80$ following the projectile fragmentation of a ${}^{92}\mathrm{Mo}$ primary beam. Previously unobserved decays have been identified in the $N=Z+2$ nuclei ${}_{39}^{80}\mathrm{Y}$ and ${}_{41}^{84}\mathrm{Nb}$ and the $N=Z$ nucleus, ${}_{43}^{86}\mathrm{Tc},$ making the latter the heaviest $N=Z$ nucleus to date in which a discrete \ensuremath{\gamma}-ray transition has been assigned. The lifetime of the previously reported ${I}^{\ensuremath{\pi}}={\frac{9}{2}}^{+}$ isomeric state in ${}^{73}\mathrm{Kr}$ has also been measured and a clearer picture of its decay properties has been deduced. Isomeric ratios have been measured and have been interpreted in terms of the yrast or nonyrast nature of the isomeric state.

Decay studies of very neutron-deficient nuclei ranging from 39Ti to 49Ni have been performed during a projectile fragmentation experiment at the GANIL/LISE3 separator. For all nuclei studied in this work, 39,40Ti, 42,43Cr, 46Mn, 45,46,47Fe and 49Ni, half-lives and decay spectra have been measured. In a few cases, gamma coincidence measurements helped to successfully identify the initial and final states of transitions. In these cases, partial decay scheme are proposed. For the most exotic isotopes, 39Ti, 42Cr, 45Fe and 49Ni, which are candidates for two-proton radioactivity from the ground state, no clear evidence of this process is seen in our spectra and we conclude rather on a delayed particle decay., Comment: 12 pages, 15 figures, submitted for publication in Eur. Phys. J. A

This contribution reports on the cross section measurements performed at GSI on the isotopic distribution of the residual nuclides of spallation reactions in inverse kinematics. The fragment separator (FRS) was used to select and identify the reaction products, and the full (Z,N) map was measured above the production limit of 0.1 mb. The high resolution of the spectrometer allowed to determine the velocity distributions of all products. These data are relevant for the design of accelerator-driven subcritical reactors. They are also of the highest importance to improve the understanding of the spallation mechanism.

If simplified, every information retrieval problem can be solved when the information need implied by its expression has been identified. We are interested in the criteria used in realising a good information retrieval problem expression. We have listed these criteria through some principles and maxims which first characterized the communication between two persons are applied. We choose to use the gricean maxims because they are the most favoured for this type of situation. Secondly, we have tried to identify some others principles that can be used to realise a good information retrieval problem expression. The principles by Grice can not resolve all forms of error associated with this particular form of communication. In our work, we defined three other principles namely: adhesion principle, reformulation principle, memorization principle. We give some examples of situations where the principles we have formulated are not applicable and the consequences. We present the possible applications of our new model: MIRABEL, which can help in the description of information retrieval problem from. It also compels its user to use essential good expression principle implicitly.