| 1. |
- Aksyutina, Yu, et al.
(författare)
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Lithium isotopes beyond the drip line
- 2008
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 666:5, s. 430-434
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Tidskriftsartikel (refereegranskat)abstract
- The unbound isotopes 10Li, 12Li and 13Li have been observed after nucleon-knockout reactions at relativistic energies with 11Li and 14Be beams impinging on a liquid hydrogen target. The channels , and were analysed in the ALADIN-LAND setup at GSI. The 10Li data confirm earlier findings, while the 12Li and 13Li nuclei were observed for the first time. The relative-energy spectrum shows that the ground state of 12Li can be described as a virtual s-state with a scattering length of -13.7(1.6) fm. A broad energy spectrum was found for the channel. Based on the assumption that the relative-energy spectrum is dominated by a correlated background presumably stemming from initial correlations in the 14Be ground-state, evidence for a 13Li resonance at 1.47(31) MeV above the threshold with a width around 2 MeV has been found.
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| 2. |
- Aksyutina, Yuliya, 1983, et al.
(författare)
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Properties of the 7He ground state from 8He neutron knockout
- 2009
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 679:3, s. 191-196
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Tidskriftsartikel (refereegranskat)abstract
- The unbound nucleus 7He, produced in neutron-knockout reactions with a 240 MeV/u 8He beam in a liquid-hydrogen target, has been studied in an experiment at the ALADIN-LAND setup at GSI. From an R-matrix analysis the resonance parameters for 7He as well as the spectroscopic factor for the 6He(0+) + n configuration in its ground-state have been obtained. The spectroscopic factor is 0.61 confirming that 7He is not a pure single-particle state. An analysis of 5He data from neutron-knockout reactions of 6He in a carbon target reveals the presence of an s-wave component at low energies in the α+n relative energy spectrum. A possible low-lying exited state in 7He observed in neutron knockout data from 8He in a carbon target and tentatively interpreted as a Iπ=1/2− state, could not be observed in the present experiment. Possible explanations of the shape difference between the 7He resonance obtained in the two knockout reactions are discussed in terms of target-dependence or different reaction mechanisms at relativistic energies.
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| 3. |
- Ballarini, F., et al.
(författare)
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The physics of the FLUKA code : Recent developments
- 2007
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Ingår i: Advances in Space Research. - Elsevier : Elsevier BV. - 0273-1177 .- 1879-1948. ; 40:9, s. 1339-1349
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Tidskriftsartikel (refereegranskat)abstract
- FLUKA is a Monte-Carlo code able to simulate interaction and transport of hadrons, heavy ions and electromagnetic particles from few keV (or thermal neutron) to cosmic ray energies in whichever material. The highest priority in the design and development of the code has always been the implementation and improvement of sound and modern physical models. A summary of the FLUKA physical models is given, while recent developments are described in detail: among the others, extensions of the intermediate energy hadronic interaction generator, refinements in photon cross sections and interaction models, analytical on-line evolution of radio-activation and remnant dose. In particular, new developments in the nucleus-nucleus interaction models are discussed. Comparisons with experimental data and examples of applications of relevance for space radiation are also provided.
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| 4. |
- Battistoni, G., et al.
(författare)
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Generator of neutrino-nucleon interactions for the FLUKA based simulation code
- 2009
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Ingår i: American Institute of Physics Conference Series. - American Institute of Physics : AIP. ; , s. 343-346
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Konferensbidrag (refereegranskat)abstract
- An event generator of neutrino-nucleon and neutrino-nucleus interactions has been developed for the general purpose Monte Carlo code FLUKA. The generator includes options for simulating quasi-elastic interactions, the neutrino-induced resonance production and deep inelastic scattering. Moreover, it shares the hadronization routines developed earlier in the framework of the FLUKA package for simulating hadron-nucleon interactions. The simulation of neutrino-nuclear interactions makes use of the well developed PEANUT event generator implemented in FLUKA for modeling of the interactions between hadrons and nuclei. The generator has been tested in the neutrino energy range from 0 to 10 TeV and it is available in the standard FLUKA distribution. Limitations related to some particular kinematical conditions are discussed. A number of upgrades is foreseen for the generator which will optimize its applications for simulating experiments in the CNGS beam.
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| 5. |
- Battistoni, G., et al.
(författare)
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Neutrino Interactions with FLUKA
- 2009
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Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 40:9, s. 2491-2505
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Tidskriftsartikel (refereegranskat)abstract
- A new neutrino interaction generator has been developed in FLUKA. The package, called NUNDIS (NeUtrino–Nucleon Deep Inelastic Scattering), is specifically built in order to be fully integrated with the hadronization and nuclear models of the FLUKA Monte Carlo code which were already successfully tested in hadronic interactions. This generator thus complements the already existing generator of quasi-elastic neutrino scattering. Here we describe the physics, sampling methods, and other specifics of NUNDIS, as well as the limitations of the code.
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| 6. |
- Battistoni, G., et al.
(författare)
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Secondary Cosmic Ray Particles due to GCR Interactions in the Earth’s Atmosphere
- 2008
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Ingår i: Exotic Nuclei and Nuclear/Particle Astrophysics (II). - American Institute of Physics : AIP. ; , s. 449-454
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Konferensbidrag (refereegranskat)abstract
- Primary GCR interact with the Earth's atmosphere originating atmospheric showers, thus giving rise to fluxes of secondary particles in the atmosphere. Electromagnetic and hadronic interactions interplay in the production of these particles, whose detection is performed by means of complementary techniques in different energy ranges and at different depths in the atmosphere, down to the Earth's surface.Monte Carlo codes are essential calculation tools which can describe the complexity of the physics of these phenomena, thus allowing the analysis of experimental data. However, these codes are affected by important uncertainties, concerning, in particular, hadronic physics at high energy. In this paper we shall report some results concerning inclusive particle fluxes and atmospheric shower properties as obtained using the FLUKA transport and interaction code. Some emphasis will also be given to the validation of the physics models of FLUKA involved in these calculations.
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| 7. |
- Battistoni, G., et al.
(författare)
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The FLUKA code and its use in hadron therapy
- 2008
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Ingår i: Nuovo Cimento della Societa Italiana di Fisica C. - Italian Physical Society. - 1124-1896. ; 31:1, s. 69-75
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Tidskriftsartikel (refereegranskat)abstract
- FLUKA is a multipurpose Monte Carto code describing transport and interaction with matter of a, large variety of particles over a wide energy range ill complex geometries. FLUKA is successfully applied ill several fields, including, but not only particle physics, cosmic-ray physics, dosimetry, radioprotection, hadron therapy. space radiation, accelerator design and neutronics. Here we briefly review recent model developments and provide examples of applications to hadron therapy, including calculation of physical and biological dose for comparison with analytical treatment planning engines as well as beta(+)-activation for therapy monitoring by means of positron emission tomography.
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| 8. |
- Doornenbal, P., et al.
(författare)
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Spectroscopy of 32Ne and the "œIsland of Inversion"
- 2009
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Ingår i: Physical Review Letters. - American Physical Society. - 0031-9007 .- 1079-7114. ; 103:3, s. 032501-1-032501-4
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Tidskriftsartikel (refereegranskat)abstract
- We report on the first spectroscopic study of the N = 22 nucleus 32Ne at the newly completed RIKEN Radioactive Ion Beam Factory. A single γ-ray line with an energy of 722(9) keV was observed in both inelastic scattering of a 226 MeV=u 32Ne beam on a carbon target and proton removal from 33Na at 245 MeV=u. This transition is assigned to the deexcitation of the first Jπ = 2+ state in 32Ne to the 0+ ground state. Interpreted through comparison with state-of-the-art shell-model calculations, the low excitation energy demonstrates that the ‘‘island of inversion’’ extends to at least N = 22 for the Ne isotopes.
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| 9. |
- Kanungo, R., et al.
(författare)
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One-Neutron Removal Measurement Reveals O-24 as a New Doubly Magic Nucleus
- 2009
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 102:15
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Tidskriftsartikel (refereegranskat)abstract
- The first measurement of the momentum distribution for one-neutron removal from O-24 at 920A MeV performed at GSI, Darmstadt is reported. The observed distribution has a width (FWHM) of 99 +/- 4 MeV/c in the projectile rest frame and a one-neutron removal cross section of 63 +/- 7 mb. The results are well explained with a nearly pure 2s(1/2) neutron spectroscopic factor of 1.74 +/- 0.19 within the eikonal model. This large s-wave probability shows a spherical shell closure thereby confirming earlier suggestions that O-24 is a new doubly magic nucleus.
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| 10. |
- Lantz, Mattias, 1971-
(författare)
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Investigations of Reaction Cross Sections for Protons and 3He
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The reaction cross section gives the probability that a particle will undergo a nonelastic process when passing through a nuclear medium. Therefore reaction cross section data are of importance both for theoretical studies and for applications in such diverse fields as medicine, biology, astrophysics and accelerator-driven transmutation of nuclear waste.There exist many data sets with angular distributions of elastic scattering, but very few measurements of the complementary reaction cross section have been performed. The measurement is in principle simple but has in practice proved to be very difficult to perform, and the relatively limited amount of experimental data displays some serious inconsistencies.Results from measurements of reaction cross sections are presented for:• 3He on 9Be, 12C, 16O, 28Si, 40Ca, 58,60Ni, 112,116,118,120,124Sn and 208Pb at 96, 138 and 167 MeV• protons on 12C, 40Ca, 90Zr and 208Pb at six energies in the energy range 80-180 MeV, and on58Ni at 81 MeV.Experimental uncertainties were 3-9% for 3He and 1.5-8% for protons.The apparatus and the experimental method used for the measurements of reaction cross sections, using a modified attenuation technique, is described. The detection method enables simultaneous measurements of reaction cross sections for five different sizes of the solid angles in steps from 99.0 to 99.8% of the total solid angle. The final results are obtained by extrapolation to the full solid angle.Experimental results are compared with predictions from optical model calculations using phenomenological global optical potentials.Phenomenological parametrizations of reaction cross sections for scattering of projectiles on targets are presented. The parametrizations show that reaction cross sections are very sensitive to matter distributions at very large radii of both the projectile and the target. For protons the derived relations makes it possible to predict the reaction cross sections on targets for which no experimental data exist.
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