Amaldi, U., Bonomi, R., Braccini, S., Crescenti, M., Degiovanni, A., Garlasche, M., et al. (2010). Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs. Nucl. Instrum. Methods Phys. Res. A, 620(2-3), 563–577.
Abstract: Hadrontherapy with protons and carbon ions is a fast developing methodology in radiation oncology. The accelerators used and planned for this purpose are reviewed starting from the cyclotrons used in the thirties. As discussed in the first part of this paper, normal and superconducting cyclotrons are still employed, together with synchrotrons, for proton therapy while for carbon ion therapy synchrotrons have been till now the only option. The latest developments concern a superconducting cyclotron for carbon ion therapy, fast-cycling high frequency linacs and 'single room' proton therapy facilities. These issues are discussed in the second part of the paper by underlining the present challenges, in particular the treatment of moving organs.
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Garcia-Recio, C., Nieves, J., & Tolos, L. (2010). D mesic nuclei. Phys. Lett. B, 690(4), 369–375.
Abstract: The energies and widths of several D-0 meson bound states for different nuclei are obtained using a D-meson selfenergy in the nuclear medium, which is evaluated in a selfconsistent manner using techniques of unitarized coupled-channel theory. The kernel of the meson-baryon interaction is based on a model that treats heavy pseudoscalar and heavy vector mesons on equal footing, as required by heavy quark symmetry. We find D-0 bound states in all studied nuclei, from C-12 up to Pb-208. The inclusion of vector mesons is the keystone for obtaining an attractive D-nucleus interaction that leads to the existence of D-0-nucleus bound states, as compared to previous studies based on SU(4) flavor symmetry. In some cases, the half widths are smaller than the separation of the levels, what makes possible their experimental observation by means of a nuclear reaction. This can be of particular interest for the future PANDA@FAIR physics program. We also find a D+ bound state in C-12, but it is too broad and will have a significant overlap with the energies of the continuum.
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Yamagata-Sekihara, J., & Oset, E. (2010). V P gamma radiative decay of resonances dynamically generated from the vector meson-vector meson interaction. Phys. Lett. B, 690(4), 376–381.
Abstract: We evaluate the radiative decay into a vector, a pseudoscalar and a photon of several resonances dynamically generated from the vector-vector interaction. The process proceeds via the decay of one of the vector components into a pseudoscalar and a photon, which have an invariant mass distribution very different from phase space as a consequence of the two vector structure of the resonances. Experimental work along these lines should provide useful information on the nature of these resonances.
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HADES Collaboration(Agakishiev, G. et al), Diaz, J., & Gil, A. (2010). Origin of the low-mass electron pair excess in light nucleus-nucleus collisions. Phys. Lett. B, 690(2), 118–122.
Abstract: We report measurements of electron pair production in elementary p + p and d + p reactions at 1.25 GeV/mu with the HADES spectrometer. For the first time, the electron pairs were reconstructed for n + p reactions by detecting the proton spectator from the deuteron breakup. We find that the yield of electron pairs with invariant mass Me+e- > 0.15 GeV/c(2) is about an order of magnitude larger in n + p reactions as compared to p + p. A comparison to model calculations demonstrates that the production mechanism is not sufficiently described yet. The electron pair spectra measured in C + C reactions are compatible with a superposition of elementary n + p and p + p collisions, leaving little room for additional electron pair sources in such light collision systems.
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Baron, R., Boucaud, P., Carbonell, J., Deuzeman, A., Drach, V., Farchioni, F., et al. (2010). Light hadrons from lattice QCD with light (u, d), strange and charm dynamical quarks. J. High Energy Phys., 06(6), 111–31pp.
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Albertus, C., Hernandez, E., & Nieves, J. (2010). Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons. Phys. Lett. B, 690(3), 265–271.
Abstract: We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way.
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Jimenez, R., Kitching, T., Pena-Garay, C., & Verde, L. (2010). Can we measure the neutrino mass hierarchy in the sky? J. Cosmol. Astropart. Phys., 05(5), 035–14pp.
Abstract: Cosmological probes are steadily reducing the total neutrino mass window, resulting in constraints on the neutrino-mass degeneracy as the most significant outcome. In this work we explore the discovery potential of cosmological probes to constrain the neutrino hierarchy, and point out some subtleties that could yield spurious claims of detection. This has an important implication for next generation of double beta decay experiments, that will be able to achieve a positive signal in the case of degenerate or inverted hierarchy of Majorana neutrinos. We find that cosmological experiments that nearly cover the whole sky could in principle distinguish the neutrino hierarchy by yielding 'substantial' evidence for one scenario over the another, via precise measurements of the shape of the matter power spectrum from large scale structure and weak gravitational lensing.
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de Azcarraga, J. A., & Izquierdo, J. M. (2010). n-ary algebras: a review with applications. J. Phys. A, 43(29), 293001–117pp.
Abstract: This paper reviews the properties and applications of certain n-ary generalizations of Lie algebras in a self-contained and unified way. These generalizations are algebraic structures in which the two-entry Lie bracket has been replaced by a bracket with n entries. Each type of n-ary bracket satisfies a specific characteristic identity which plays the role of the Jacobi identity for Lie algebras. Particular attention will be paid to generalized Lie algebras, which are defined by even multibrackets obtained by antisymmetrizing the associative products of its n components and that satisfy the generalized Jacobi identity, and to Filippov (or n-Lie) algebras, which are defined by fully antisymmetric n-brackets that satisfy the Filippov identity. 3-Lie algebras have surfaced recently in multi-brane theory in the context of the Bagger-Lambert-Gustavsson model. As a result, Filippov algebras will be discussed at length, including the cohomology complexes that govern their central extensions and their deformations ( it turns out that Whitehead's lemma extends to all semisimple n-Lie algebras). When the skewsymmetry of the Lie or n-Lie algebra bracket is relaxed, one is led to a more general type of n-algebras, the n-Leibniz algebras. These will be discussed as well, since they underlie the cohomological properties of n-Lie algebras. The standard Poisson structure may also be extended to the n-ary case. We shall review here the even generalized Poisson structures, whose generalized Jacobi identity reproduces the pattern of the generalized Lie algebras, and the Nambu-Poisson structures, which satisfy the Filippov identity and determine Filippov algebras. Finally, the recent work of Bagger-Lambert and Gustavsson on superconformal Chern-Simons theory will be briefly discussed. Emphasis will be made on the appearance of the 3-Lie algebra structure and on why the A(4) model may be formulated in terms of an ordinary Lie algebra, and on its Nambu bracket generalization.
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Mathieu, V., & Vento, V. (2010). eta-eta ' mixing in the flavor basis and large N. Phys. Lett. B, 688(4-5), 314–318.
Abstract: The mass matrix for eta-eta' is derived in the flavor basis at O(p(4)) of the chiral Lagrangian using the large N approximation. Under certain assumptions, the mixing angle phi = 41.4 degrees and the decay constants ratio f(K)/f(pi) = 1.15 are calculated in agreement with the data. It appears that the FKS scheme arises as a special limit of the chiral Lagrangian. Their mass matrix is obtained without the hypothesis on the mixing pattern of the decay constants.
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Aparici, A., Santamaria, A., & Wudka, J. (2010). A model for right-handed neutrino magnetic moments. J. Phys. G, 37(7), 075012–12pp.
Abstract: A simple extension of the standard model providing Majorana magnetic moments to right-handed neutrinos is presented. The model contains, in addition to the standard model particles and right-handed neutrinos, just a singly charged scalar and a vector-like charged fermion. The phenomenology of the model is analysed and its implications in cosmology, astrophysics and lepton flavour violating processes are extracted. If light enough, the charged particles responsible for the right-handed neutrino magnetic moments could copiously be produced at the Large Hadron Collider.
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