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Orrigo, S. E. A. et al, Rubio, B., Agramunt, J., Algora, A., & Molina, F. (2015). β-delayed γ-proton decay in 56Zn: analysis of the charged-particle spectrum. Acta Phys. Pol. B, 46(3), 709–712.
Abstract: A study of the beta decay of the proton-rich T-z = 2 nucleus Zn-56 has been reported in a recent publication. A rare and exotic decay mode, beta-delayed gamma-proton decay, has been observed there for the first time in the fp shell. Here, we expand on some of the details of the data analysis, focussing on the charged particle spectrum.
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Domingo-Pardo, C. (2016). Beta-delayed neutron emission: first measurements in the heavy mass region and future prospects. Acta Phys. Pol. B, 47(3), 729–737.
Abstract: Beta-delayed neutrons play a key role in the formation of heavy elements in explosive stellar environments. The final r-process abundance distribution, including the rare-earth peak, is tailored to a large extent by the neutrons released after the beta decay of very exotic neutron-rich nuclei encountered along the r-process path and during the freeze-out phase. Such scenarios involve a vast amount of – yet undiscovered – nuclei, and most of them are expected to be neutron emitters. In this respect, existing beta-delayed neutron emission data is rather scarce, spanning from the lightest isotopes up to the region of the fission-fragments with masses up to A similar to 150. This contribution gives an overview on the latest measurements of neutron branching ratios in the heavy mass region around N = 126, which was practically unexplored in the past. Present plans to access very exotic nuclei at the RIB-facility of RIKEN in the framework of the BRIKEN project, are presented, together with the expected impact in r-process nucleosynthesis studies.
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IGISOL Collaboration(Briz, J. A. et al), Algora, A., Tain, J. L., Guadilla, V., Agramunt, J., Estevez, E., et al. (2016). Total absorption spectroscopy of fission fragments relevant for reactor antineutrino spectra determination. Acta Phys. Pol. B, 47(3), 755–762.
Abstract: The contribution of each fission fragment to the reactor antineutrino spectra was determined using the summation method based on the existing information on fission yields and decay data contained in nuclear databases and the reactor evolution code MURE. The beta decay of some of the main contributors has been studied using the Total Absorption Spectroscopy (TAS) technique during two experimental campaigns at the IGISOL facility, in Jyvaskyla (Finland). Results on the decay of Rb-92, the most important contributor in the 4-8 MeV energy region are reported. The status of the analysis of the second experiment is presented as well.
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AGATA Collaboration(Krzysiek, M. et al), & Gadea, A. (2016). Gamma decay of the possible 1(-) two-phonon state in Ce-140 excited via inelastic scattering of O-17. Acta Phys. Pol. B, 47(3), 859–866.
Abstract: The gamma decay from the low-lying dipole states of Ce-140 excited via inelastic scattering of O-17 at bombarding energy of 340 MeV was measured using the high resolution AGATA-Demonstrator array in coincidence with scattered ions detected in two segmented Delta E-E silicon detectors of the TRACE array. Particular attention is here given to the decay of the first 1(-) state at 3643 keV which is considered to be of two-phonon character. The gamma-gamma coincidence method was applied to select desired decay branch. No direct decay from this state was observed to 2(+) and 3(-) phonon states which would be the proof of the pure harmonic coupling. The comparison between experimentally obtained differential cross sections and analysis with distorted wave Born approximation (DWBA) allowed to conclude that the first 1(-) state has a different nature than higher-lying pygmy dipole states. This was possible using the form factor obtained by folding a microscopically calculated transition density.
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Fujita, Y., Rubio, B., Molina, F., Adachi, T., Fujita, H., Blank, B., et al. (2016). The Tz = ±1 → 0 and ±2 →±1 Mirror Gamow–Teller transitions in pf-shell nuclei. Acta Phys. Pol. B, 47(3), 867–881.
Abstract: Gamow-Teller (GT) transitions are the most common weak-interaction processes in the Universe. They play important roles in various processes of nucleosynthesis, for example, in the rapid proton-capture process (rp-process). In the pf-shell region, the rp-process runs through neutron-deficient nuclei with T-z = -2, -1, and 0 mainly by means of GT and Fermi transitions, where T-z is the z component of isospin T defined by T-z = (N = Z)/2. Under the assumption of isospin symmetry, mirror nuclei with reversed Z and N numbers, and thus with opposite signs of T-z, have the same structure. Therefore, symmetry is also expected for the GT transitions starting from and ending up in mirror nuclei. We have been studying the T-z = -2 -> -1 and -1 -> 0 GT transitions in beta decays, while those from stable T-z = +2 and +1 nuclei by means of hadronic (He-3; t) charge-exchange (CE) reactions. The results from these studies are compared in order to examine the mirror-symmetry structure in nuclei. In addition, these results are combined for the better understanding of GT transitions in the pf-shell region.
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Oset, E., Bayar, M., Dote, A., Hyodo, T., Khemchandani, K. P., Liang, W. H., et al. (2016). Two-, Three-, Many-body Systems Involving Mesons. Multimeson Condensates. Acta Phys. Pol. B, 47(2), 357–365.
Abstract: In this paper, we review results from studies with unconventional many-hadron systems containing mesons: systems with two mesons and one baryon, three mesons, some novel systems with two baryons and one meson, and finally, systems with many vector mesons, up to six, with their spins aligned forming states of increasing spin. We show that in many cases, one has experimental counterparts for the states found, while in some other cases, they remain as predictions, which we suggest to be searched in BESIII, Belle, LHCb, FAIR and other facilities.
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Bernabeu, J. (2016). Discrete Symmetries CP,T,CPT. Acta Phys. Pol. B, 47(2), 417–424.
Abstract: The role of symmetry breaking mechanisms to search for new physics is of highest importance. We discuss the status and prospects of the discrete symmetries CP, T, CPT looking for their separate violation in LHC experiments and meson factories.
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Biagi, N., Francesconi, S., Gessner, M., Bellini, M., & Zavatta, A. (2022). Remote Phase Sensing by Coherent Single Photon Addition. Adv. Quantum Technol., 5(12), 2200039–9pp.
Abstract: A remote phase sensing scheme is proposed, inspired by the high sensitivity of the entanglement produced by coherent multimode photon addition on the phase set in the remote heralding apparatus. By exploring the case of delocalized photon addition over two modes containing identical coherent states, the optimal observable to perform remote phase estimation from heralded quadrature measurements is derived. The technique is experimentally tested with calibration measurements and then used for estimating a remote phase with a sensitivity that is found to scale with the intensity of the local coherent states, which never interacted with the sample.
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Minakata, H., & Pena-Garay, C. (2012). Solar Neutrino Observables Sensitive to Matter Effects. Adv. High. Energy Phys., 2012, 349686–15pp.
Abstract: We discuss constraints on the coefficient A(MSW) which is introduced to simulate the effect of weaker or stronger matter potential for electron neutrinos with the current and future solar neutrino data. The currently available solar neutrino data leads to a bound A(MSW) = 1.47(+0.54)(-0.42)((-0.82)(+1.88)) at 1 sigma (3 sigma) CL, which is consistent with the Standard Model prediction A(MSW) = 1. For weaker matter potential (A(MSW) < 1), the constraint which comes from the flat B-8 neutrino spectrum is already very tight, indicating the evidence for matter effects. However for stronger matter potential (A(MSW) > 1), the bound is milder and is dominated by the day-night asymmetry of B-8 neutrino flux recently observed by Super-Kamiokande. Among the list of observables of ongoing and future solar neutrino experiments, we find that (1) an improved precision of the day-night asymmetry of B-8 neutrinos, (2) precision measurements of the low-energy quasi-monoenergetic neutrinos, and (3) the detection of the upturn of the B-8 neutrino spectrum at low energies are the best choices to improve the bound on A(MSW).
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Lesgourgues, J., & Pastor, S. (2012). Neutrino Mass from Cosmology. Adv. High. Energy Phys., 2012, 608515–34pp.
Abstract: Neutrinos can play an important role in the evolution of the universe, modifying some of the cosmological observables. In this contribution we summarize the main aspects of cosmological relic neutrinos, and we describe how the precision of present cosmological data can be used to learn about neutrino properties, in particular their mass, providing complementary information to beta decay and neutrinoless double-beta decay experiments. We show how the analysis of current cosmological observations, such as the anisotropies of the cosmic microwave background or the distribution of large-scale structure, provides an upper bound on the sum of neutrino masses of order 1 eV or less, with very good perspectives from future cosmological measurements which are expected to be sensitive to neutrino masses well into the sub-eV range.
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