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The isotopic distributions of fragments produced in the spallation. of uranium are strongly influenced by the fission of the excited prefragments, highly fissile nuclei. The competition between fission and evaporation around the doubly-magic nucleus Pb is discussed. The light fragments from Fe beam are produced with a strong enhancement of even-even nuclei compared to the odd-odd in the region of nuclei with equal number of neutrons and protons, N similar to Z. This staggering in the production of light fragments is not observed in the production of heavy fragments, and is in contradiction with the basis of the statistical model of deexcitation of a hot nucleus. Pairing interaction as a function of the excitation energy and as a function of the isospin of the nucleus are questioned.

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.

We report on an experimental programme to measure the nuclide production in fission in inverse kinematics. Using relativistic beams of primordial and radioactive nuclei, new experimental information on the influence of shell effects on fission has been obtained. The transition from symmetric to asymmetric fission around 227Th has systematically been mapped. The heavy asymmetric component was found to be astonishingly stable near Z = 54 for all systems investigated.

The next generation of 4 pi arrays for high-precision gamma -ray spectroscopy will involve "gamma -ray tracking front-end on digital signal processing techniques, which allows to extract energy, timing and spatial information on the interactions of a gamma -ray in the Ge detector by pulse shape analysis of its signals. Utilizing the information on the positions of the interaction points and the energies released at each point the tracks of the gamma -rays in a Ge shell can be reconstructed in three dimensions.

The neutron-rich isotope 136Sb has been produced following the relativistic projectile fission of 238U in an experiment performed at the Fragment Separator at GSI, Darmstadt. Delayed γ-ray spectroscopy of the fission products has been performed after isotope separation. A new isomeric state in 136Sb has been populated, and its lifetime measured as T1/2 = 565(50) ns. Realistic and empirical shell-model calculations have been performed and are compared to the experimental observables.

Interactions of 197Au projectiles at 800 A MeV with protons leading to fission are investigated. We measured the production cross sections and velocities of all fission residues which are fully identified in atomic and mass number by using the in-flight separator FRS at GSI. The new data are compared with earlier measurements of the characteristics of fission in similar reactions. Both the production cross sections and the recoil energies are relevant for a better understanding of spallation reactions.

Formation cross sections of isotopes produced in inverse kinematics from the spallation/fragmentation and fission of 197Au (at 800 A⋅MeV), 208Pb (at 1 A⋅GeV) and 238U (at 1 A⋅GeV) are presented. These data are extremely important for the design of acceleratordriven systems and new radioactive-ion-beam facilities. The data have been measured at GSI with the FRagment Separator, which allows precise measurements of the cross sections of the fragments and of their velocities. The knowledge of the velocity enables to deduce the reaction mechanisms and leads to a better understanding of the physics of intermediateenergy nuclear reactions. Thanks to this, nuclear models capable to predict the isotopic formation cross sections have been implemented and benchmarked with the measured data. Results are presented.

Spallation residues produced in 1 GeV per nucleon 208Pb on proton reactions have been studied using the Fragment Separator facility at GSI. Isotopic production cross sections of elements from 61Pm to 82Pb 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.

Gamma-rays de-exciting a millisecond isomer in the neutron-rich nucleus 74/190W116 have been observed following relativistic projectile fragmentation of a 1 GeV per nucleon 208Pb beam. The isomeric decay populates the ground-state rotational band, with energies that indicate a significant deformation change at Z = 74 for the N = 116 isotones. The successful application of the projectile fragmentation technique in a region of deformed nuclei opens up the prospect of exploiting K-isomer decays to probe the evolution of collective nuclear structure far from the valley of beta stability. (C) 2000 Elsevier Science B.V.

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.

The level scheme of 226U has been deduced from the results of two experiments carried out at the University of Jyvaskyla, Finland. Both α- and γ-ray-spectroscopic techniques have been employed. The interleaved states of positive- and negative-parity indicate the octupole nature of this nucleus, and the behavior of the difference in aligned angular momentum between the positive- and negative-parity bands as a function of rotational frequency is consistent with that expected for a rotating reflection-asymmetric shape.

Spallation experiments in inverse kinematics have been performed at GSI. The momentum distributions and the isotopic production cross sections have been measured. The data are relevant for the design of accelerator-driven subcritical reactors.

Fission of 238U induced in collisions at 1 A GeV with lead has systematically been studied. A complete survey on the isotopic production cross sections of about 600 fission fragments of all elements between gallium (Z=31) and praseodymium (Z=59) is given. These fission fragments and about 600 fragmentation products have been identified in the GSI fragment separator FRS from magnetic rigidities, time-of-flight values, and the energy loss in an ionisation chamber. In addition, the momentum distributions of all these reaction products have been mapped, and the products are unambiguously attributed to the different reaction mechanisms due to their kinematical properties. The results are compared with less comprehensive previous data. The recoil velocity induced in the fission process by the Coulomb repulsion of the fragments allows to identify the average charge of the fissioning nucleus in hot fission.

The gas-filled recoil separator RITU at the Department of Physics, University of Jyvaskyla (JYFL) was constructed in 1992–1993, and the first experiments were performed in late 1993. RITU differs from other gas-filled separators by having a vertically focusing quadrupole magnet in front of the separating dipole for better matching with the dipole acceptance. New results from RITU include the discovery of 13 previously unpublished isotopes of At, Rn, Fr, Ra, Ac and Th, while experiments in the transuranium region have also been made. Illustrative examples from these studies together with results on background properties, efficiency of separation, and other performance data will be presented.

Neutron-deficient α-decaying nuclei have been produced using fusion-evaporation reactions. A gas-filled recoil separator was used to separate the fusion products from the scattered beam. The activities were implanted in a position sensitive silicon detector. The isotopes were identified using spatial and time correlations between implants and decays. During ten years of operation time about twenty new α-decaying isotopes have been identified in the translead region. In addition numerous α-decay studies have been performed on already known isotopes yielding much improved precision for the measured decay properties. An overview of the α-decay studies performed for the translead nuclei employing the gas-filled recoil separator will be given.

Alpha-decay properties of the isotope 191At were investigated for the first time and the decay properties of 193At and 195At were studied with improved accuracy. The nuclei were produced in fusion-evaporation reactions of 54Fe and 56Fe ions with 141Pr and 142Nd targets. The fusion products were separated in-flight using the gas-filled recoil separator RITU and implanted into a position-sensitive silicon detector. The isotopes were identified using position, time and energy correlations between the implants and subsequent alpha decays. New information concerning the low-lying states in the corresponding alpha-decay daughter nuclei 187Bi, 189Bi and 191Bi was also gained using alpha-gamma coincidences.

Neutron-deficient uranium isotopes were studied via α spectroscopic methods. A low-lying α-decaying isomeric state was found in 218U. The new isomeric state was assigned spin and parity Iπ=8+. The isomer decays by α emission with an energy E = 10678(17)keV and with a half-life T1/2 = (0.56+0.26-0.14)ms. The known alpha-decay properties of the ground state of 218U was measured with improved statistics. The ground-state α-decay has an energy E = 8612(9)keV and a half-life T1/2 = (0.51+0.17-0.10)ms.

This measurement represents the first observation of a non-yrast band in the 186Pb nucleus by employing the Recoil-Decay Tagging (RDT) technique. Previously known yrast levels have been confirmed and the band is extended up to level I π = (16+).

The electron antineutrino background from reactors is estimated in proposed LAGUNA sites using commercial fission reactors operational in 2009. Calculations are made for an input to background studies like e.g. geoneutrino measurement uncertainty estimation.

Strong evidence for the existence of previously postulated deformed excited states in $^{98}\mathrm{Zr}_{58}$ has been obtained by an accurate measurement of the ${\mathrm{\ensuremath{\rho}}}^{2}$(${0}_{3}^{+}$\ensuremath{\rightarrow}${0}_{2}^{+}$) value for the decay of the second excited ${0}^{+}$ state at 1436 keV. In the neighboring isotope $^{99}\mathrm{Zr}_{59}$, at the edge of the region of strong ground-state deformation, evidence is found for a rotational band built on the state at 614 keV. Systematics of the excitation energies of the deformed states in Zr nuclei and their Sr neighbors show that the apparent sudden onset of deformation is explained by the steady lowering of a strongly deformed potential minimum. Therefore, an extra strong interaction between proton-neutron spin-orbit partners, acting in the ${0}_{2}^{+}$ states, need not be invoked to explain the origin of the sudden onset of deformation.

International audience; More than 600 residual nuclei, formed in the spallation of 136Xe projectiles impinging on deuterium at 500AMeV of incident energy, have been unambiguously identified and their production cross sections have been determined with high accuracy. By comparing these data to others previously measured for the reactions 136Xe + p at 1AGeV and 136Xe + p at 500AMeV we investigated the role that neutrons play in peripheral collisions and to understand the energy dissipation in frontal collisions in spallation

Neutron deficient mercury isotopes were produced in the reaction 36Ar + 144Sm using bombarding energies of 180–230 MeV. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. An alpha line with the alpha particle energy and half-life of (7069±11) keV and (2.1−0.7+1.8) ms, respectively, was assigned to the new mercury isotope 174Hg.

The Pyhasalmi Mine is the deepest operational base-metal mine in Europe. The existing caverns in the old mine at levels 95 m – 1080 m can be used for scientific purposes. The new mine extends down to 1440 metres where the mining goes on, probably until the year 2017. It is technically possible to construct very large laboratory caverns at 1400 – 1500 levels (4000 – 4200 m.w.e.), at reasonable cost. The stable bedrock, modern infrastructure, and good traffic conditions all around the year give excellent opportunities for the research of underground physics. The CUPP project (Centre for Underground Physics in Pyhasalmi) aims at establishing an underground research facility in the mine. It is run by the University of Oulu, and it receives funding from the Regional Development Fund of the EU. The first major experiment [1] will measure the multiplicity and the lateral distribution of cosmicray muons. The measured data are used to obtain information on the composition of cosmic rays at the knee region (10 – 10 eV), with the purpose to clarify the origin of cosmic rays and the kink in the spectrum. The experiment consists of large drift chambers used previously at DELPHI, and plastic scintillators as auxiliary underground detectors and surface array. The prototype is under construction at the 210 m level. Smaller experiments have been carried out in the mine. The measurements of the backgrounds, like muon fluxes and rock radioactivity at different depths, will be continued, with the permanent monitoring of the fluxes being the aim. The facility is suitable for neutrino experiments. Low-cost supernova neutrino experiments are under consideration, to be located in the available caverns at the 660 m level. These detectors may be also used for other purposes like monitoring the muon and neutron fluxes. The proposed new laboratory at 1500 m level could host very large experiments that cannot be located elsewhere. Several initiatives are around, one of the most interesting being the LENA (Low Energy Neutrino Astronomy)[2] experiment. It is an international initiative to build a large-volume liquid scintillation detector to observe solar neutrinos, supernova neutrinos, geoneutrinos, and to search for proton decay. The size of the detector would be about 90 metres (length) times 20 metres (diameter) and the mass about 30 ktons. The Pyhasalmi mine is considered as one of the possible locations of the detector. In the next decade, the Pyhasalmi mine might host the far detector for a possible neutrino factory at CERN. The distance is interestingly 2288 km. Other baselines and sources are also possible and provide their own physical goals. Simulations of neutrino oscillations related to long baseline experiments are being done[3].

The new radon isotope197Rn was produced in the reaction169Tm(35Cl, 7n)197Rn using bombarding energies from 5.6 to 6.1 MeV/nucleon. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. The alpha particle energy and half-life of197Rn were measured to be (7260±7) keV and (65 −14 +25 ) ms, respectively. Another new alpha line was assigned to an isomeric state in197Rn for which an alpha particle energy of (7356±7) keV and a half-life of (19 −4 +8 ) ms were obtained.

The francium isotopes200–202Fr were produced in the reaction35Cl+170Yb using bombarding energies of 4.9–5.3 MeV/nucleon. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. An alpha line with the alpha particle energy and half-life of (7468±9) keV and (19 −6 +13 ) ms, respectively, was assigned to200Fr. Previously reported decay properties of201,202Fr were confirmed.

Two new neutron-deficient isotopes207,208Ac have been produced in fusion reactions with 5.2–5.6 MeV/nucleon40Ar ions on175Lu and identified on the basis of genetic correlations. The fusion evaporation products were separated on-line using a gas-filled magnetic recoil separator. The alpha energy and half-life of208Ac were determined to be (7572±15) keV and (95 −16 +24 ) ms, respectively. A new alpha line with a half-life of (25 −5 +9 ) ms and an energy of (7758±20) keV is assigned to the decay of an isomeric state in208Ac. Another new activity with a half-life of (22 −9 +40 ) ms and an alpha energy of (7712±25) keV is assigned to207Ac.

Experiments of spallation in inverse kinematics were performed at GSI. The isotopic distribution cross-sections of the residual nuclides of spallation were measured for each element. The fragment separator (FRS) was used to select and identify the reaction products, and the full (Z, N) map was measured. The velocity distributions of all products are determined with the high resolution of the spectrometer, which give further information on the reaction mechanism. 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.

The excited states in the neutron-deficient isotopes Rn have been populated using the Er(Ar,4n), Er(Ar,4n), and Er(Ar,4n) reactions at beam energies of 175, 182, and 177 MeV, respectively. Evaporation residues were selected using an in-flight gas-filled separator and implanted at the focal plane into a 16-element position-sensitive, passivated ion-implanted planar silicon detector. Prompt γ rays were observed at the target position using an array of Compton-suppressed germanium detectors. Correlation with the subsequent radioactive decay of associated recoiling ions in the silicon detector, recoil-γ and recoil-γ-γ coincidences were used to construct decay schemes of light radon isotopes. Measurements of delayed y rays at the focal plane have also been made, and microsecond isomers have been observed in Rn, but not in Rn. Comparison of the results with those for polonium isotopes indicate a common mechanism for the onset of deformation. Candidates have been found in Rn for deformed intruder states which coexist with the spherical ground-state shape.

Une connaissance precise de tous les noyaux produits par spallation est necessaire pour predire la radioactivite et les modifications chimiques induites dans une cible de spallation. Des donnees experimentales obtenues par la technique de la cinematique inverse sont presentees. De nouveaux resultats preliminaires plus complets sont aussi presentes. Ces mesures de production d'isotopes dans le fer permettent d'estimer directement les alterations et dommages generes dans une fenetre metallique d'un ADS.

The nuclei 226U and 230Pu have been populated via reactions involving 208Pb targets bombarded by 22Ne and 26Mg projectiles. Fusion-evaporation residues were separated in-flight using a gas-filled recoil separator. A position-sensitive Si-strip detector was employed at the focal plane in order to identify correlated α-decay chains. Two fine structure α-decay lines have been observed. The first, with an energy of 7385(5) keV, is assigned as the α decay from 226U to the first excited 2+ state of 222Th. The second line, observed for the first time in this work, has an energy of 6961(30) keV and is assigned as the α decay from 230Pu to the first excited 2+ state of 226U. The excitation energy of the first excited 2+ state in 226U was determined to be 96(25) keV, giving an estimate of the deformation parameter β2≃ 0.20.

The next generation neutrino observatory proposed by the LBNO collaboration will address fundamental questions in particle and astroparticle physics. The experiment consists of a far detector, in its first stage a 20 kt LAr double phase TPC and a magnetised iron calorimeter, situated at 2300 km from CERN and a near detector based on a high-pressure argon gas TPC. The long baseline provides a unique opportunity to study neutrino flavour oscillations over their 1st and 2nd oscillation maxima exploring the $L/E$ behaviour, and distinguishing effects arising from $\delta_{CP}$ and matter. In this paper we have reevaluated the physics potential of this setup for determining the mass hierarchy (MH) and discovering CP-violation (CPV), using a conventional neutrino beam from the CERN SPS with a power of 750 kW. We use conservative assumptions on the knowledge of oscillation parameter priors and systematic uncertainties. The impact of each systematic error and the precision of oscillation prior is shown. We demonstrate that the first stage of LBNO can determine unambiguously the MH to $>5\sigma$C.L. over the whole phase space. We show that the statistical treatment of the experiment is of very high importance, resulting in the conclusion that LBNO has $\sim$ 100% probability to determine the MH in at most 4-5 years of running. Since the knowledge of MH is indispensable to extract $\delta_{CP}$ from the data, the first LBNO phase can convincingly give evidence for CPV on the $3\sigma$C.L. using today's knowledge on oscillation parameters and realistic assumptions on the systematic uncertainties.