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We summarize the evidence for DM-like anomalies in neutron multiplicity spectra collected underground with Pb targets by three independent experiments: NEMESIS (at 210 m.w.e.) NMDS (at 583 m.w.e.), and ZEPLIN-II (at 2850 m.w.e.). A new analysis shows small but persistent anomalies at high neutron multiplicities. Adjusted for differences in detection efficiencies, the positions of the anomalies are consistent between the three systems. Also, the intensities match when corrected for the acquisition time and estimated detection efficiency. While the three measurements are inconclusive when analyzed separately, together, they exclude a statistical fluke to better than one in a million. To prove the existence of the anomalies above the 5-sigma discovery threshold, we propose to upgrade the current NEMESIS setup. The upgrade concept and the critical components of the new experiment are described. The upgraded setup would already acquire the needed data sample during the first year of operation. Additional information, vital for the physics interpretation of the analysis, will be obtained with a Cu target.

The experiment was performed at the GSI facility in Darmstadt (Germany).; Around 270 medium-mass residual nuclei, formed in spallation reactions induced by 136Xe projectiles impinging on a liquid hydrogen target at 500 AMeV, have been unambiguously identified at GSI using the magnetic spectrometer FRS. The individual production cross sections and the longitudinal momentum distributions have been determined with high accuracy. These data represent an important constraint for theoretical models describing spallation reactions.

The production cross sections of fragmentation-evaporation residues in the reaction Pb+p at 500 A MeV have been measured using the inverse-kinematics method and the FRS spectrometer (GSI). Fragments were identified in nuclear charge using ionisation chambers. The mass identification was performed event-by-event using the Bρ-TOF-ΔE technique. Although partially-unresolved ionic charge states induced an ambiguity on the mass of some heavy fragments, production rates could be obtained with a high accuracy by systematically accounting for the polluting ionic charge states. The contribution of multiple reactions in the target was subtracted using a new, partly self-consistent code. The isobaric distributions are found to have a shape very close to the one observed in experiments at higher energy. Kinematic properties of the fragments were also measured. The total and the isotopic cross sections, including charge-pickup cross sections, are in good agreement with previous measurements and models. The data are discussed in the light of previous spallation measurements, especially on lead at 1 GeV. © 2006 Elsevier B.V. All rights reserved.

Fission fragments from 1 A GeV 238U ions impinging a hydrogen target are investigated by using the fragment separator FRS for magnetic selection of reaction products including ray-tracing, and ΔE-ToF techniques. On the basis of the kinematics of the fragments, binary fission can be assigned as production process up to very heavy fragments. Fission fragments are separated and identified as far as 184Re for the first time. Cross sections are measured and found in the range of 500 μb to 5 μb. Isobaric cross sections decrease smoothly with increasing masses. Beyond tungsten, fission fragments are hidden in the more abundant spallation evaporation residues. 283 isotopes of elements gadolinium to rhenium in the mass range 147 to 184 are observed and cross sections measured. All the fragments are formed by fission of excited parent nuclei following emission of a cascade of secondary neutrons.

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.

High resolution measurements with a magnetic spectrometer show a post-acceleration of the projectile-like residues produced in relativistic heavy-ion collisions. The observed post-acceleration increases with the mass loss of the residual fragments. Lighter residues are observed to be produced at velocities even higher than the projectile. A dependence with the mass of the target and the energy of beam is also observed. This effect is interpreted as the response of the projectile spectator to the participant blast indicating a momentum dependence of the nuclear mean field.

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.

The techniques of recoil-gating and recoil-decay tagging have been employed at Jyvaskyla to perform in-beam γ-ray and electron spectroscopy studies of heavy nuclei. The JUROSPHERE γ-ray array and the SACRED electron spectrometer have been placed at the target position of the JYFL gas-filled recoil separator recoil ion transport unit (RITU). The RITU separator has been used to collect the recoils of interest and separate them from beam particles and fission products. At the focal plane a detector system consisting of time-of-flight and implantation detectors has been used for further event identification. The method and some highlights from the results in the lead region close to the proton drip line and in the transuranium region will be presented and discussed.

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.

This contribution discusses the recoil-isomer tagging technique and its application to study isomeric states near the mass 140 proton drip line. The recoiling nuclei from a fusion-evapn. reaction were implanted into a silicon detector at the focal plane of a gas-filled separator, where prompt and delayed g-ray transitions were correlated across isomeric states. New states were established upon a known 15 ms isomer in 142Tb and the feeding and decay of a new 0.5(2)ms isomeric state was established in 144Ho. This measurement represents the first observation of excited states in 144Ho. [on SciFinder (R)]

The next generation of 4 pi arrays for high-precision gamma -ray spectroscopy will involve gamma -ray tracking detectors. They consist of high-fold segmented Ge detectors and a front-end electronics, based on new digital signal processing techniques, which allows to extract energy, timing and spatial information for a gamma -ray by pulse shape analysis of the Ge detector 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 production cross sections and longitudinal-momentum distributions of very neutron-rich isotopes have been investigated in the fragmentation of a 950 A MeV 179 Au beam in a beryllium target. Seven new isotopes ( 193 Re, 194 Re, 191 W, 192 W, 189 Tl, 187 Hf and 188 Hf) and the five-proton-removal channel were observed for the first time. The reaction mechanism leading to the formation of these very neutron-rich isotopes is explained in terms of the cold-fragmentation process. An analytical model describing this reaction mechanism is presented.

Fission induced by 197 Au on proton collisions is investigated in order to study the nuclear viscosity in highly excited nuclear matter. The isotopic identification of the fission residues allows to determine the mean values of the mass number, nuclear charge and excitation energy of the fissioning nuclei at saddle. The comparison of these properties with statistical fission calculations evidences the role of the nuclear viscosity in the description of the fission dynamics.

Excited Jπ=0+ states in 188 Pb populated in the α-decay of 192 Po have been identified through α-particle/conversion electron coincidences. α-particle energies and branching ratios have been measured, and hindrance factors deduced. The level scheme has been fitted using a configuration mixing calculation, providing estimates of the mixing matrix elements, mixing amplitudes and the energies of unperturbed and unobserved levels.

An experiment to observe simultaneous, multiple muon events originating from extensive air showers is under preparation. The experiment will be situated in shallow depths in the Pyhasalmi mine in Finland, where the existing free caverns will be used. The aim is to cover an area of about 200 - 300 m(2). The detection of the multimuon events is motivated by partly unknown composition of the primary cosmic rays in the energy region of 10(15) - 10(16) eV, i.e. the 'knee' region. A prototype detector is under construction and is expected to be running at the spring 2005.

A gas-filled recoil separator for the study of heavy elements has been constructed. The separator is of type QDQQ with the first, vertically focusing, quadrupole providing improved matching to the acceptance of the dipole magnet. The separator has been designed also for use in vacuum mode in which case a mass resolving power of ≈ 100 is estimated. The deflection angle is 25° and the radius of curvature is 1850 mm. Maximum beam rigidity is 2.2 T m. In the first experiments, new isotopes in the region Z = 85–90 have been synthesized.

A combination of the proton-induced fission of 238 U and the on-line mass separation based on the ion-guide technique has been applied in the study of neutron-rich Mo-isotopes. The decays of 106,108 Mo have been studied by using gamma-, beta-, X-ray and conversion-electron spectroscopy. The decay scheme of 106 Mo has been revised and a beta-decay half-life of 8.73(12) s has been measured for this nucleus. A beta-decay half-life of 1.09(2) s and a decay energy of 5120(40) keV have been measured for 108 Mo. The decay scheme of 108 Mo has been constructed and altogether 29 new transitions have been placed in the decay scheme. The beta-decay strengths of 102,104,106,108 Mo have been deduced from the experimental data and are compared with the Gamow-Teller strength obtained from a macroscopic-microscopic calculation. The role of the asymptotic quantum numbers in the context of the allowed beta decay is discussed. Additionally, the experimental half-lives and the decay energies are compared to the recent half-life and atomic-mass predictions.

A new gas-filled recoil separator, intended mainly for the study of reaction products in mass region of 100–200 produced in symmetric or nearly symmetric reactions, is under design at the Department of Physics in the University of Jyvaskyla. The separator will be of the type DQQ where a horizontally focusing dipole (D) is followed by a quadrupole (Q) doublet. The bending radius of the dipole magnet will be 1850 mm and the bending angle 50°.

Decay of 113Rh to the levels of 113Pd was studied at the IGISOL-facility by means of β-, γ- and conversion-electron spectroscopy. The level scheme of 113Pd was constructed using 33 gamma transitions on the basis of observed γγ-coincidence relations and half-life analysis. A β-decay half-life of (2.80±0.12) s was measured for 113Rh. A new 9 − 2 isomeric state with (0.3 ± 0.1) s half-life and excitation energy 81.3 keV was discovered in 113Pd. This state and the other recently observed low-lying 9 − 2 or 11 − 2 isomeric states in 115,117Pd isotopes are directly populated in proton-induced fission. The decay of these isomers is unusually strongly hindered compared with Weisskopf estimates. Our observation of two strongly hindered M2 transitions in 113,117Pd with hindrance factors of 7600 and 6800, respectively, imply coexistence of nuclear shapes in odd-A Pd nuclei.

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.

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].