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n_TOF Collaboration(Weiss, C. et al), Domingo-Pardo, C., Giubrone, G., & Tain, J. L. (2014). The (n,alpha) Reaction in the s-process Branching Point Ni-59. Nucl. Data Sheets, 120, 208–210.
Abstract: The (n,alpha) reaction in the radioactive Ni-59 is of relevance in nuclear astrophysics as Ni-59 can be considered as the first branching point in the astrophysical s-process. Its relevance in nuclear technology is especially related to material embrittlement in stainless steel. However, there is a discrepancy between available experimental data and the evaluated nuclear data files for this reaction. At the n_TOF facility at CERN, a dedicated system based on sCVD diamond diodes was set up to measure the Ni-59(n,alpha)Fe-56 cross section. The results of this measurement, with special emphasis on the dominant resonance at 203 eV, are presented here.
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n_TOF Collaboration(Lederer, C. et al), Giubrone, G., Domingo-Pardo, C., & Tain, J. L. (2014). Neutron Capture Reactions on Fe and Ni Isotopes for the Astrophysical s-process. Nucl. Data Sheets, 120, 201–204.
Abstract: Neutron capture cross sections in the keV neutron energy region are the key nuclear physics input to study the astrophysical slow neutron capture process. In the past years, a series of neutron capture cross section measurements has been performed at the neutron time-of-flight facility n_TOF at CERN focussing on the Fe/Ni mass region. Recent results and future developments in the neutron time-of-flight technique are discussed.
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Estienne, M., Fallot, M., Cormon, S., Algora, A., Bui, V. M., Cucoanes, A., et al. (2014). Contribution of Recently Measured Nuclear Data to Reactor Antineutrino Energy Spectra Predictions. Nucl. Data Sheets, 120, 149–152.
Abstract: The aim of this work is to study the impact of the inclusion of the recently measured beta decay properties of the Tc-102,Tc-104,Tc-105,Tc-106,Tc-107, Mo-105, and Nb-101 nuclei in the calculation of the antineutrino (anti-nu) energy spectra arising after the fissions of the four main fissile isotopes U-235,U-238, and (PU)-P-239,241 in PWRs. These beta feeding probabilities, measured using the Total Absorption Technique (TAS) at the JYFL facility of Jyvaskyla, have been found to play a major role in the gamma component of the decay heat for Pu-239 in the 4-3000 s range. Following the fission product summation method, the calculation was performed using the MCNP Utility Reactor Evolution code (MURE) coupled to the experimental spectra built from beta decay properties of the fission products taken from evaluated databases. These latest TAS data are found to have a significant effect on the Pu isotope energy spectra and on the spectrum of U-238 showing the importance of their measurement for a better assessment of the reactor anti-nu energy spectrum, as well as importance for fundamental neutrino physics experiments and neutrino applied physics.
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Caballero-Folch, R. et al, Domingo-Pardo, C., Tain, J. L., Agramunt, J., Algora, A., & Rubio, B. (2014). beta-decay and beta-delayed Neutron Emission Measurements at GSI-FRS Beyond N=126, for r-process Nucleosynthesis. Nucl. Data Sheets, 120, 81–83.
Abstract: New measurements of very exotic nuclei in the neutron-rich region beyond N=126 have been performed at the GSI facility with the fragment separator (FRS). The aim of the experiment is to determine half-lives and beta-delayed neutron emission branching ratios of isotopes of Hg, Tl and Pb in this region. This contribution summarizes final counting statistics for identification and for implantation, as well as the present status of the data analysis of the half-lives. In summary, isotopes of Pt, Au, Hg, Ti, Pb, Bi, Po, At, Rn and Fr were clearly identified and several of them (Hg208-211, Tl211-215, Pb214-218) were implanted with enough statistics to determine their half-lives. About half of them are expected to be neutron emitters, in such cases it will become possible to obtain the neutron emission probabilities, P-n.
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Martinez, T. et al, Agramunt, J., Algora, A., Domingo-Pardo, C., Jordan, M. D., Rubio, B., et al. (2014). MONSTER: a TOF Spectrometer for beta-delayed Neutron Spectroscopy. Nucl. Data Sheets, 120, 78–80.
Abstract: beta-delayed neutron (DN) data, including emission probabilities, P-n, and energy spectrum, play an important role in our understanding of nuclear structure, nuclear astrophysics and nuclear technologies. A MOdular Neutron time-of-flight SpectromeTER (MONSTER) is being built for the measurement of the neutron energy spectra and branching ratios. The TOF spectrometer will consist of one hundred liquid scintillator cells covering a significant solid angle. The MONSTER design has been optimized by using Monte Carlo (MC) techniques. The response function of the MONSTER cell has been characterized with mono-energetic neutron beams and compared to dedicated MC simulations.
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Agramunt, J. et al, Algora, A., Domingo-Pardo, C., Jordan, D., Rubio, B., Tain, J. L., et al. (2014). New Beta-delayed Neutron Measurements in the Light-mass Fission Group. Nucl. Data Sheets, 120, 74–77.
Abstract: A new accurate determination of beta-delayed neutron emission probabilities from nuclei in the low mass region of the light fission group has been performed. The measurements were carried out using the BELEN 4 pi neutron counter at the IGISOL-JYFL mass separator in combination with a Penning trap. The new results significantly improve the uncertainties of neutron emission probabilities for Br-91, As-86, As-85, and Ge-85 nuclei.
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Rubio, B. et al, Orrigo, S. E. A., Montaner-Piza, A., Agramunt, J., Algora, A., & Molina, F. (2014). Beta Decay Study of the T-z =-2 Zn-56 Nucleus and the Determination of the Half-Lives of a Few fp-shell Nuclei. Nucl. Data Sheets, 120, 37–40.
Abstract: This paper concerns the experimental study of the beta decay properties of few proton-rich fp-shell nuclei. The nuclei were produced at GANIL in fragmentation reactions, separated with the LISE spectrometer and stopped in an implantation detector surrounded by Ge detectors. The beta-delayed gammas, beta-delayed protons and the exotic beta-delayed gamma-proton emission have been studied. Preliminary results are presented. The decay of the T-z = -2 nucleus Zn-56 has been studied in detail. Information from the beta-delayed protons and beta-delayed gammas has been used to deduce the decay scheme. The exotic beta-delayed gamma-proton decay has been observed for the first time in the fp-shell. The interpretation of the data was made possible thanks to the detailed knowledge of the mirror Charge Exchange (CE) process and the gamma de-excitation of the states in Co-56, the mirror nucleus of Cu-56.
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Algora, A. et al, Valencia, E., Tain, J. L., Jordan, M. D., Agramunt, J., Rubio, B., et al. (2014). Total Absorption Study of Beta Decays Relevant for Nuclear Applications and Nuclear Structure. Nucl. Data Sheets, 120, 12–15.
Abstract: An overview is given of our activities related to the study of the beta decay of neutron rich nuclei relevant for nuclear applications. Recent results of the study of the beta decay of Br-87,Br-88 using a new segmented total absorption spectrometer are presented. The measurements were performed at the IGISOL facility using trap-assisted total absorption spectroscopy.
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Vijande, J., Valcarce, A., Carames, T. F., & Richard, J. M. (2014). Multiquark Systems. Few-Body Syst., 55(8-10), 675–681.
Abstract: In this talk we tackle the description of hadron spectroscopy in terms of the constituent quark model. We focus on the mesonic charm sector, where several of the new reported resonances seem to defy their classification as simple quark-antiquark states. We pay special attention to higher order Fock space components in describing excited states of the meson spectra in close connection with the hadron-hadron interaction. The main goal of the present study is a coherent understanding of the low-energy hadron phenomenology without enforcing any particular model, to constrain its characteristics and learn about low-energy realization of the theory.
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Anderson, L. et al, & Mena, O. (2014). The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: measuring D-A and H at z=0.57 from the baryon acoustic peak in the Data Release 9 spectroscopic Galaxy sample. Mon. Not. Roy. Astron. Soc., 439(1), 83–101.
Abstract: We present measurements of the angular diameter distance to and Hubble parameter at z = 0.57 from the measurement of the baryon acoustic peak in the correlation of galaxies from the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey. Our analysis is based on a sample from Data Release 9 of 264 283 galaxies over 3275 square degrees in the redshift range 0.43 < z < 0.70. We use two different methods to provide robust measurement of the acoustic peak position across and along the line of sight in order to measure the cosmological distance scale. We find D-A(0.57) = 1408 +/- 45 Mpc and H(0.57) = 92.9 +/- 7.8 km s(-1) Mpc(-1) for our fiducial value of the sound horizon. These results from the anisotropic fitting are fully consistent with the analysis of the spherically averaged acoustic peak position presented in Anderson et al. Our distance measurements are a close match to the predictions of the standard cosmological model featuring a cosmological constant and zero spatial curvature.
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