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http://hdl.handle.net/10261/61
2014-12-18T12:35:24ZFlavoured CP asymmetries for type II seesaw leptogenesis
http://hdl.handle.net/10261/108645
Title: Flavoured CP asymmetries for type II seesaw leptogenesis
Authors: González Felipe, Ricardo; Joaquim, F. R.; Serodio, Hugo
Abstract: A novel contribution to the leptonic CP asymmetries in type II seesaw leptogenesis scenarios is obtained for the cases in which flavor effects are relevant for the dynamics of leptogenesis. In the so-called flavored leptogenesis regime, the interference between the tree-level amplitude of the scalar triplet decaying into two leptons and the one-loop wave function correction with leptons in the loop, leads to a new nonvanishing CP asymmetry contribution. The latter conserves total lepton number but violates lepton flavor. Cases in which this novel contribution may be dominant in the generation of the baryon asymmetry are briefly discussed.2014-12-11T13:36:51ZShedding Light on Dark Matter at Colliders
http://hdl.handle.net/10261/108644
Title: Shedding Light on Dark Matter at Colliders
Authors: Mitsou, Vasiliki A.
Abstract: Dark matter remains one of the most puzzling mysteries in Fundamental Physics of our times. Experiments at high-energy physics colliders are expected to shed light to its nature and determine its properties. This review focuses on recent searches for dark matter signatures at the Large Hadron Collider, also discussing related prospects in future e(+)e(-) colliders.2014-12-11T13:26:33ZThe soliton-soliton interaction in the Chiral Dilaton Model
http://hdl.handle.net/10261/108643
Title: The soliton-soliton interaction in the Chiral Dilaton Model
Authors: Mantovani, Valentina; Park, Byung-Yoon; Vento, Vicente
Abstract: We study the interaction between two B = 1 states in the Chiral Dilaton Model where baryons are described as nontopological solitons arising from the interaction of chiral mesons and quarks. By using the hedgehog solution for B = 1 states we construct, via a product ansatz, three possible B = 2 configurations to analyse the role of the relative orientation of the hedgehog quills in the dynamics of the soliton-soliton interaction and investigate the behavior of these solutions in the range of long/intermediate distance. One of the solutions is quite binding due to the dynamics of the pi and sigma fields at intermediate distance and should be used for nuclear matter studies. Since the product ansatz break down as the two solitons get close, we explore the short range distance regime with a model that describes the interaction via a six-quark bag ansatz. We calculate the interaction energy as a function of the inter-soliton distance and show that for small separations the six quarks bag, assuming a hedgehog structure, provides a stable bound state that at large separations connects with a special configuration coming from the product ansatz.2014-12-11T13:19:59ZA Comprehensive Mechanism Reproducing the Mass and Mixing Parameters of Quarks and Leptons
http://hdl.handle.net/10261/108642
Title: A Comprehensive Mechanism Reproducing the Mass and Mixing Parameters of Quarks and Leptons
Authors: Baker, Michael J.; Bordes, José; Hong-Mo, Chan; Tsun, Tsou Sheung
Abstract: It is shown that if, from the starting point of a universal rank-one mass matrix long favored by phenomenologists, one adds the assumption that it rotates (changes its orientation in generation space) with changing scale, one can reproduce, in terms of only six real parameters, all the 16 mass ratios and mixing parameters of quarks and leptons. Of these 16 quantities so reproduced, 10 for which data exist for direct comparison (i.e. the CKM elements including the CP-violating phase, the angles theta(12), theta(13), theta(23) in nu-oscillation, and the masses m(c), m(mu), m(e)) agree well with experiment, mostly to within experimental errors; four others (m(s), m(u), m(d), m(nu 2)), the experimental values for which can only be inferred, agree reasonably well; while two others (m(nu 1), delta(CP) for leptons), not yet measured experimentally, remain as predictions. In addition, one gets as bonuses, estimates for (i) the right-handed neutrino mass m(nu R) and (ii) the strong CP angle theta inherent in QCD. One notes in particular that the output value for sin(2) 2 theta(13) from the fit agrees very well with recent experiments. By inputting the current experimental value with its error, one obtains further from the fit two new testable constraints: (i) that theta(23) must depart from its "maximal" value: sin(2) 2 theta(23) similar to 0.935 +/- 0.021, (ii) that the CP-violating (Dirac) phase in the PMNS would be smaller than in the CKM matrix: of order only vertical bar sin delta(CP)vertical bar <= 0.31 if not vanishing altogether.2014-12-11T13:08:50ZDEPFET Active Pixel Detectors for a Future Linear e(+)e(-) Collider
http://hdl.handle.net/10261/108640
Title: DEPFET Active Pixel Detectors for a Future Linear e(+)e(-) Collider
Authors: DEPFET collaboration; Alonso, Óscar; Boronat Arévalo, Marçà; Esperante Pereira, Daniel; Fuster, Juan; García García, Ignacio; Lacasta Llácer, Carlos; Oyanguren, Arantza; Ruiz Valls, Pablo; Timón Grau, Guillermo; Vos, Marcel; Curras, E.; López Virto, A.; Moya, D.; Vila, Iván
Abstract: The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 mu m. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling, and services. In this paper, the status of the DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear e(+)e(-) collider.2014-12-11T12:33:39ZNeutrino masses and mixing: a flavour symmetry roadmap
http://hdl.handle.net/10261/108638
Title: Neutrino masses and mixing: a flavour symmetry roadmap
Authors: Morisi, Stefano; Valle, José W. F.
Abstract: Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete symmetries, which provide a simple way to account for the TBM pattern. We discuss phenomenological implications such as neutrinoless double beta decay, lepton flavour violation as well as theoretical aspects such as the possibility to explain quarks and leptons within a common framework, such as grand unified models2014-12-11T12:01:08ZThe Baryon Number Two System in the Chiral Soliton Model
http://hdl.handle.net/10261/108636
Title: The Baryon Number Two System in the Chiral Soliton Model
Authors: Mantovani, Valentina; Drago, Alessandro; Vento, Vicente; Park, Byung-Yoon
Abstract: We study the interaction between two B = 1 states in a chiral soliton model where baryons are described as non-topological solitons. By using the hedgehog solution for the B = 1 states we construct three possible B = 2 configurations to analyze the role of the relative orientation of the hedgehog quills in the dynamics. The strong dependence of the intersoliton interaction on these relative orientations reveals that studies of dense hadronic matter using this model should take into account their implications.2014-12-11T11:43:08ZOn the corner elements of the CKM and PMNS matrices
http://hdl.handle.net/10261/108635
Title: On the corner elements of the CKM and PMNS matrices
Authors: Baker, Michael J.; Bordes, José; Hong-Mo, Chan; Tsun, Tsou Sheung
Abstract: Recent experiments show that the top-right corner element (U-e3) of the PMNS matrix is small but nonzero, and suggest further via unitarity that it is smaller than the bottom-left corner element (U-tau 1). Here, it is shown that if to the assumption of a universal rank-one mass matrix, long favoured by phenomenologists, one adds that this matrix rotates with scale, then it follows that A) by inputting the mass ratios m(c)/m(t), m(s)/m(b), m(mu)/m(tau), and m(2)/m(3), i) the corner elements are small but nonzero, ii) V-ub < V-td, U-e3 < U-tau 1, iii) estimates result for the ratios V-ub/V-td and U-e3/U-tau 1, and B) by inputting further the experimental values of V-us, V-tb and U-e2, U-mu 3, iv) estimates result for the values of the corner elements themselves. All the inequalities and estimates obtained are consistent with present data within expectation for the approximations made.2014-12-11T11:32:15ZHawking effect in BECs acoustic white holes
http://hdl.handle.net/10261/108633
Title: Hawking effect in BECs acoustic white holes
Authors: Balbinot, Roberto; Fabbri, Alessandro; Mayoral Sáenz, Carlos
Abstract: Bogoliubov pseudoparticle creation in a BEC undergoing a WH-like flow is investigated analytically in the case of a one-dimensional geometry with stepwise homogeneous regions. Comparison of the results with those corresponding to a BH flow is performed. The implications for the analogous gravitational problem is discussed.2014-12-11T11:18:03ZStandard model and new physics contributions to K (L) and K (S) into four leptons
http://hdl.handle.net/10261/108631
Title: Standard model and new physics contributions to K (L) and K (S) into four leptons
Authors: D'Ambrosio, Giancarlo; Greynat, David; Vulvert, Grégory
Abstract: We study the K (L) and K (S) decays into four leptons (, , ) where we use a form factor motivated by vector meson dominance, and show the dependence of the branching ratios and spectra from the slopes. A precise determination of short-distance contribution to K (L) ->mu mu is affected by our ignorance on the sign of the amplitude but we show a possibility to measure the sign of this amplitude by studying K (L) and K (S) decays in four leptons. We also investigate the effect of New Physics contributions for these decays.2014-12-11T11:07:19Z