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San Francesco al Campo, Italy

Vasquez J.C.,ICTP | Vasquez J.C.,International School for Advanced Studies | Vasquez J.C.,Gran Sasso Science Institute
Journal of High Energy Physics | Year: 2015

Abstract: We compute a T-odd triple vector correlation for the μ → eγ decay and the μ → e conversion process, finding simple results in terms of the CP violating phases of the effective Hamiltonians. Then we focus on the minimal Left-Right symmetric extension of the Standard Model, which can lead to an appreciable correlation. We show that under rather general assumptions, this correlation can be used to discriminate between Parity or Charge-conjugation as the discrete Left-Right symmetry. © 2015, The Author(s). Source

Nesti F.,Gran Sasso Science Institute | Salucci P.,International School for Advanced Studies
Journal of Cosmology and Astroparticle Physics | Year: 2013

We derive the mass model of the Milky Way (MW), crucial for Dark Matter (DM) direct and indirect detection, using recent data and a cored dark matter (DM) halo profile, which is favoured by studies of external galaxies. The method used consists in fitting a spherically symmetric model of the Galaxy with a Burkert DM halo profile to available data: MW terminal velocities in the region inside the solar circle, circular velocity as recently estimated from maser star forming regions at intermediate radii, and velocity dispersions of stellar halo tracers for the outermost Galactic region. The latter are reproduced by integrating the Jeans equation for every modeled mass distribution, and by allowing for different velocity anisotropies for different tracer populations. For comparison we also consider a Navarro-Frenk-White profile. We find that the cored profile is the preferred one, with a shallow central density of ρH ∼ 4 × 107M⊙/kpc 3 and a large core radius RH ∼ 10 kpc, as observed in external spirals and in agreement with the mass model underlying the Universal Rotation Curve of spirals. We describe also the derived model uncertainties, which are crucially driven by the poorly constrained velocity dispersion anisotropies of halo tracers. The emerging cored DM distribution has implications for the DM annihilation angular profile, which is much less boosted in the Galactic center direction with respect to the case of the standard ΛCDM, NFW profile. Using the derived uncertainties we discuss finally the limitations and prospects to discriminate between cored and cusped DM profile with a possible observed diffuse DM annihilation signal. The present mass model aims to characterize the present-day description of the distribution of matter in our Galaxy, which is needed to frame current crucial issues of Cosmology, Astrophysics and Elementary Particles. © 2013 IOP Publishing Ltd and Sissa Medialab srl. Source

Taylor A.M.,Dublin Institute for Advanced Studies | Gabici S.,University Paris Diderot | Aharonian F.,Dublin Institute for Advanced Studies | Aharonian F.,Max Planck Institute for Nuclear Physics | Aharonian F.,Gran Sasso Science Institute
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

Recent IceCube results suggest that the first detection of very high energy astrophysical neutrinos have been accomplished. We consider these results at face value in a Galactic origin context. Emission scenarios from both the Fermi bubble and broader halo region are considered. We motivate that such an intensity of diffuse neutrino emission could be Galactic in origin if it is produced from an outflow into the halo region. This scenario requires cosmic ray transport within the outflow environment to be different to that inferred locally within the disk and that activity in the central part of the Galaxy accelerates cosmic rays to trans-"knee" energies before they escape into an outflow. The presence of a large reservoir of gas in a very extended halo around the Galaxy, recently inferred from x-ray observations, implies that the relatively modest acceleration power of 1039 erg s-1 in PeV energy cosmic rays may be sufficient to explain the observed neutrino flux. Such a luminosity is compatible with that required to explain the observed intensity of cosmic rays around the knee. © 2014 American Physical Society. Source

Bertolini S.,International School for Advanced Studies | Maiezza A.,University of Valencia | Nesti F.,Ruder Boskovic Institute | Nesti F.,Gran Sasso Science Institute
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

We revisit the ΔF=2 transitions in the K and Bd,s neutral meson systems in the context of the minimal left-right symmetric model. We take into account, in addition to up-to-date phenomenological data, the contributions related to the renormalization of the flavor-changing neutral Higgs tree-level amplitude. These contributions were neglected in recent discussions, albeit formally needed in order to obtain a gauge-independent result. Their impact on the minimal LR model is crucial and twofold. First, the effects are relevant in B meson oscillations, for both CP conserving and CP violating observables, so that for the first time these imply constraints on the LR scenario which compete with those of the K sector (plagued by long-distance uncertainties). Second, they sizably contribute to the indirect kaon CP violation parameter . We discuss the bounds from B and K mesons in both cases of LR symmetry: generalized parity (P) and charge conjugation (C). In the case of P, the interplay between the CP-violation parameters and ′ leads us to rule out the regime of very hierarchical bidoublet vacuum expectation values v2/v1 Source

Antonelli P.,Gran Sasso Science Institute | Carles R.,Montpellier University | Silva J.D.,University of Lisbon
Communications in Mathematical Physics | Year: 2014

We consider the nonlinear Schrödinger equation under a partial quadratic confinement. We show that the global dispersion corresponding to the direction(s) with no potential is enough to prove global in time Strichartz estimates, from which we infer the existence of wave operators, thanks to suitable vector-fields. Conversely, given an initial Cauchy datum, the solution is global in time and asymptotically free, provided that confinement affects one spatial direction only. This stems from anisotropic Morawetz estimates, involving a marginal of the position density. © 2014, Springer-Verlag Berlin Heidelberg. Source

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