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Meloni, D., Morisi, S., & Peinado, E. (2011). Fritzsch neutrino mass matrix from S-3 symmetry. J. Phys. G, 38(1), 015003–10pp.
Abstract: We present an extension of the standard model (SM) based on the discrete flavor symmetry S-3 which gives a neutrino mass matrix with two-zero texture of Fritzsch type and nearly diagonal charged lepton mass matrix. The model is compatible with the normal hierarchy only and predicts sin(2) theta(13) approximate to 0.01 at the best-fit values of solar and atmospheric parameters and maximal leptonic CP violation.
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Ikeno, N., Yamagata-Sekihara, J., Nagahiro, H., Jido, D., & Hirenzaki, S. (2011). Formation of heavy-meson bound states by two-nucleon pick-up reactions. Phys. Rev. C, 84(5), 054609–7pp.
Abstract: We develop a model to evaluate the formation rate of the heavy mesic nuclei in two-nucleon pick-up reactions and apply it to the (6)Li target cases for the formation of heavy meson-alpha bound states, as examples. The existence of the quasideuteron in the target nucleus is assumed in this model. It is found that mesic nuclei formation in recoilless kinematics is possible even for heavier mesons than the nucleon in two-nucleon pick-up reactions. We find the formation rate of the meson-alpha bound states can be around half of the elementary cross sections at the recoilless kinematics with small distortions.
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Heinze, M., & Malinsky, M. (2011). Flavor structure of supersymmetric SO(10) GUTs with extended matter sector. Phys. Rev. D, 83(3), 035018–16pp.
Abstract: We discuss in detail the flavor structure of the supersymmetric SOd(10) grand unified models with the three traditional 16-dimensional matter spinors mixed with a set of extra ten-dimensional vector multiplets which can provide the desired sensitivity of the standard model matter spectrum to the grand unified theory symmetry breakdown at the renormalizable level. We put the qualitative argument that a successful fit of the quark and lepton data requires an active participation of more than a single vector matter multiplet on a firm, quantitative ground. We find that the strict no-go obtained for the fits of the charged-sector observables in case of a single active matter 10 is relaxed if a second vector multiplet is added to the matter sector and excellent, though nontrivial, fits can be devised. Exploiting the unique calculable part of the neutrino mass matrix governed by the SUd(2)(L) triplet in the 54-dimensional Higgs multiplet, a pair of genuine predictions of the current setting is identified: a nonzero value of the leptonic 1-3 mixing close to the current 90% C.L. limit and a small leptonic Dirac CP phase are strongly preferred by all solutions with the global-fit chi(2) values below 50.
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n_TOF Collaboration(Calviani, M. et al), Domingo-Pardo, C., & Tain, J. L. (2011). Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility. J. Korean Phys. Soc., 59(2), 1912–1915.
Abstract: Neutron-induced fission cross-sections of minor actinides have been measured using the nTOF white neutron source at CERN. Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at nTOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of (233)U, (245)cm and (243)Am from thermal to 20 MeV are here reported, together with preliminary results for (241)Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of (235)U, measured simultaneously with the same detector.
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Galli, P., Goldstein, K., Katmadas, S., & Perz, J. (2011). First-order flows and stabilisation equations for non-BPS extremal black holes. J. High Energy Phys., 06(6), 070–28pp.
Abstract: We derive a generalised form of flow equations for extremal static and rotating non-BPS black holes in four-dimensional ungauged N = 2 supergravity coupled to vector multiplets. For particular charge vectors, we give stabilisation equations for the scalars, analogous to the BPS case, describing full known solutions. Based on this, we propose a generic ansatz for the stabilisation equations, which surprisingly includes ratios of harmonic functions.
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Llosa, G., Barrio, J., Lacasta, C., Callier, S., Raux, L., & de La Taille, C. (2011). First tests in the application of silicon photomultiplier arrays to dose monitoring in hadron therapy. Nucl. Instrum. Methods Phys. Res. A, 648, S96–S99.
Abstract: A detector head composed of a continuous LaBr3 crystal coupled to a silicon photomultiplier array has been mounted and tested, for its use in a Compton telescope for dose monitoring in hadron therapy. The LaBr3 crystal has 16 mm x 18 mm x 5 mm size, and it is surrounded with reflecting material in five faces. The SiPM array has 16 (4 x 4) elements of 3 mm x 3 mm size. The SPIROC1 ASIC has been employed as readout electronics. The detector shows a linear behavior up to 1275 keV. The energy resolution obtained at 511 keV is 7% FWHM, and it varies as one over the square root of the energy up to the energies tested. The variations among the detector channels are within 12%. A preliminary measurement of the timing resolution gives 7 ns FWHM. The spatial resolution obtained with the center of gravity method is 1.2 mm FWHM. The tests performed confirm the correct functioning of the detector.
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ANTARES Collaboration(Adrian-Martinez, S. et al), Aguilar, J. A., Bigongiari, C., Dornic, D., Emanuele, U., Gomez-Gonzalez, J. P., et al. (2011). First Search For Point Sources Of High-Energy Cosmic Neutrinos With The Antares Neutrino Telescope. Astrophys. J. Lett., 743(1), L14–6pp.
Abstract: Results are presented of a search for cosmic sources of high-energy neutrinos with the ANTARES neutrino telescope. The data were collected during 2007 and 2008 using detector configurations containing between 5 and 12 detection lines. The integrated live time of the analyzed data is 304 days. Muon tracks are reconstructed using a likelihood-based algorithm. Studies of the detector timing indicate a median angular resolution of 0.5 +/- 0.1 deg. The neutrino flux sensitivity is 7.5 x 10(-8)(E(v)/GeV)(-2) GeV(-1) s(-1) cm(-2) for the part of the sky that is always visible (delta < -48 deg), which is better than limits obtained by previous experiments. No cosmic neutrino sources have been observed.
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Casas, J. A., Moreno, J. M., Rius, N., Ruiz de Austri, R., & Zaldivar, B. (2011). Fair scans of the seesaw. Consequences for predictions on LFV processes. J. High Energy Phys., 03(3), 034–22pp.
Abstract: We give a straightforward procedure to scan the seesaw parameter-space, using the common “R-parametrization”, in a complete way. This includes a very simple rule to incorporate the perturbativity requirement as a condition for the entries of the R-matrix. As a relevant application, we show that the somewhat propagated belief that BR(mu -> e, gamma) in supersymmetric seesaw models depends strongly on the value of theta(13) is an “optical effect” produced by incomplete scans, and does not hold after a careful analytical and numerical study. When the complete scan is done, BR(mu -> e, gamma) gets very insensitive to theta(13). This holds even if the right-handed neutrino masses are kept constant or under control (as is required for succesful leptogenesis). In most cases the values of BR(mu -> e, gamma) are larger than the experimental upper bound. Including (unflavoured) leptogenesis does not introduce any further dependence on theta(13), although decreases the typical value of BR(mu -> e, gamma).
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Xie, J. J., Martinez Torres, A., & Oset, E. (2011). Faddeev fixed-center approximation to the N K K(bar) system and the signature of a N*(1920)(1/2+) state. Phys. Rev. C, 83(6), 065207–8pp.
Abstract: We perform a calculation for the three-body N (K) over barK scattering amplitude by using the fixed-center approximation to the Faddeev equations, taking the interaction between N and (K) over bar, N and K, and (K) over bar and K from the chiral unitary approach. The resonant structures show up in the modulus squared of the three-body scattering amplitude and suggest that a N (K) over barK hadron state can be formed. Our results are in agreement with others obtained in previous theoretical works, which claim a new N* resonance around 1920 MeV with spin-parity J(P) = 1/2(+). The existence of these previous works allows us to test the accuracy of the fixed center approximation in the present problem and sets the grounds for possible application in similar problems, as an explorative tool to determine bound or quasibound three-hadron systems.
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Bandos, I. A., de Azcarraga, J. A., & Meliveo, C. (2011). Extended supersymmetry in massless conformal higher spin theory. Nucl. Phys. B, 853(3), 760–776.
Abstract: We propose superfield equations in tensorial N-extended superspaces to describe the N = 2,4,8 supersymmetric generalizations of free conformal higher spin theories. These can be obtained by quantizing a superparticle model in N-extended tensorial superspace. The N-extended higher spin supermultiplets just contain scalar and 'spinor' fields in tensorial space so that, in contrast with the standard (super)space approach, no nontrivial generalizations of the Maxwell or Einstein equations to tensorial space appear when N > 2. For N = 4,8, the higher spin-tensorial components of the extended tensorial superfields are expressed through additional scalar and spinor fields in tensorial space which obey the same free higher spin equations, but that are axion-like in the sense that they possess Peccei-Quinn-like symmetries.
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