Domingo-Pardo, C., Goel, N., Engert, T., Gerl, J., Kojouharov, I., Schaffner, H., et al. (2011). A novel gamma-ray imaging method for the pulse-shape characterization of position sensitive semiconductor radiation detectors. Nucl. Instrum. Methods Phys. Res. A, 643(1), 79–88.
Abstract: A new technique for the pulse-shape characterization of gamma-ray position sensitive germanium detectors is presented. This method combines the pulse shape comparison scan (PSCS) principle with a gamma-ray imaging technique. The latter is provided by a supplementary, high performance, position sensitive gamma-ray scintillator detector. We describe the basic aspects of the method and we show measurements made for the study of pulse-shapes in a non-segmented planar HPGe detector. A preliminary application of the PSCS is carried out, although a more detailed investigation is being performed with highly segmented position sensitive detectors.
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n_TOF Collaboration(Guerrero, C. et al), Domingo-Pardo, C., & Tain, J. L. (2011). Study of Photon Strength Function of Actinides: the Case of (235)U, (238)Np and (241)Pu. J. Korean Phys. Soc., 59(2), 1510–1513.
Abstract: The decay from excited levels in medium and heavy nuclei can be described in a statistical approach by means of Photon Strength Functions and Level Density distributions. The study of electromagnetic cascades following neutron capture based on the use of high efficiency detectors has been shown to be well suited for probing the properties of the Photon Strength Function of heavy (high level density) and/or radioactive (high background) nuclei. In this work we have investigated for the first time the validity of the recommended PSF of actinides, in particular (235)U, (238)Np and (241)Pu. Our study includes the search for resonance structures in the PSF below S(n) and draws conclusions regarding their existence and their characteristics in terms of energy, width and electromagnetic nature.
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n_TOF Collaboration, Gunsing, F., Berthoumieux, E., Borella, A., Belgya, T., Szentmiklosi, L., et al. (2011). Neutron Capture on (209)Bi: Determination of the Production Ratio of (210m)Bi/(210g)Bi. J. Korean Phys. Soc., 59(2), 1670–1675.
Abstract: Neutron capture on (209)Bi produces either an isomeric state (210m)Bi with a half life of 3 x 106 years, or the ground state (210g)Bi which decays with a half life of 5 days to the alpha emitter (210)Po. Therefore the neutron capture cross section ratio (209)Bi(n,gamma)(210m)Bi/(210g)Bi plays an important role in predicting the short- and long-term radio-toxicity produced by (209)Bi under neutron irradiation. This ratio is dependent on the neutron energy. We have measured this ratio for cold neutrons at the cold neutron beam facility of the Budapest Neutron Centre by observing the population of the ground-and the metastable state using high resolution gamma-ray spectroscopy. The same technique has been used at the pulsed white neutron source GELINA of the IRMM, Geel in combination with the neutron time-of-flight technique. Results for the neutron-energy dependent branching ratio will be presented. In addition we performed simulations using a statistical decay code.
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n_TOF Collaboration(Cano-Ott, D. et al), Domingo-Pardo, C., & Tain, J. L. (2011). Neutron Capture Measuremetns on Minor Actinides at the n_TOF Facility at CERN: Past, Present and Future. J. Korean Phys. Soc., 59(2), 1809–1812.
Abstract: The successful development of advanced nuclear systems for sustainable energy production and nuclear waste management depends on high quality nuclear data libraries. Recent sensitivity studies and reports [1-3] have identified the need for substantially improving the accuracy of neutron cross-section data for minor actinides. The n_TOF collaboration has initiated an ambitious experimental program for the measurement of neutron capture cross sections of minor actinides. Two experimental setups have been constructed for this purpose: a Total Absorption Calorimeter (TAC) [4] for measuring neutron capture cross-sections of low-mass and/or radioactive samples and a set of two low neutron sensitivity C(6)D(6) detectors for the less radioactive materials.
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n_TOF Collaboration(Tarrio, D. et al), Domingo-Pardo, C., Plag, R., Plompen, A., & Tain, J. L. (2011). High-energy Neutron-induced Fission Cross Sections of Natural Lead and Bismuth-209. J. Korean Phys. Soc., 59(2), 1904–1907.
Abstract: The CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure small neutron-induced fission cross sections, as those of subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors. The fragment coincidence method allows to unambiguously identify the fission events. The present experiment provides the first results for neutron-induced fission up to 1 GeV for (nat)Pb and (209)Bi. A good agreement with previous experimental data below 200 MeV is shown. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross section is close to 1 GeV.
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