Tag Archives: Evento scientifico

We propose an adjoint $SU(5)$ GUT model with a $T_{7}$ family symmetry and an extra $Z_{2}\otimes Z_{2}^{\prime} \otimes Z_{3}\otimes Z_{4}\otimes Z_{12}$ discrete group, that successfully describes the prevailing Standard Model (SM) fermion mass and mixing pattern. The observed hierarchy of the charged fermion masses and the quark mixing angles arises from the $Z_{3}\otimes Z_{4}\otimes Z_{12}$ symmetry breaking, which occurs near to the GUT scale. The light active neutrino masses are generated by type I and type III seesaw mechanisms mediated by the fermionic $SU(5)$ singlet and the adjoint $\mathbf{24}$-plet. We construct several benchmark scenarios, which lead to $SU(5)$ gauge coupling unification and are compatible with the known phenomenological constraints originating from the lightness of neutrinos, proton decay, dark matter, etc. These scenarios contain TEV scale colored fields, which could give rise to a visible signal or be stringently constrained at the LHC.

Secretary:Donatella Pierluigi

LC2015 belongs to a conference series that started in 1991 under the supervision of the International Light Cone Advisory Committee and showed, year by year, to play a vital role in promoting the research towards a rigorous description of hadrons and nuclei, based on Light-Cone quantization methods. A strong relation with the experimental activity represents an important commitment of the Light-Cone community, with the ambition ''to assist in the development of crucial experimental tests at hadron facilities''. To emphasize this goal, the LC2015 venue will be the INFN National Laboratories in Frascati. In anticipation of opportunities afforded by new facilities, such as the 12 GeV upgrade of Th. Jefferson Natl. Lab, the FAIR facility at GSI, J-PARC, and other facilities around the globe, we aim to have a scientific program that could have a stimulating impact on the forefront research development of nuclear, hadron and particle physics. In particular, LC2015 will address the following topics: Hadron Physics in present and future facilities AdS/CFT – Theory and applications Few-body problems on the Light Cone Relativistic models of nuclear and hadronic structures Nonperturbative methods in quantum field theory Light-front field theory in QCD and QED Lattice Gauge Theories      Conference Chairs   Barbara Pasquini Dipartimento di Fisica Universita' di Pavia Via Bassi 6, 27100 Pavia Tel +390382987450 Fax +390382526938 Giovanni Salmè INFN Sezione di Roma Piazzale Aldo Moro 6, 00185 Roma Tel. +390649914872 Fax +39064454749   Participants  

In this talk I will review the status of flavour physics after the first run of the LHC and in particular I will discuss recent results from the LHCb experiment suggesting possible deviations from the SM predictions in semileptonic B-meson decays. I will also discuss possible interpretations of these anomalies in terms of New Physics.

The muon particle physics program at J-PARC will be mentioned, in particular charged lepton flavor violation with muons. Muon to electron conversion in a muonic atom is a process of charged lepton flavor violation (CLFV). The COMET experiment aims to search for muon to electron conversion at J-PARC with single-event sensitivity of 3×10^{-17}. which is about 10,000 improvement over the current limit. Recently the COMET experiment has taken a staged approach. COMET Phase-I. as the first phase, aims at a single-event sensitivity of 3×10^{-15} with a partial part of the full muon beam line and a Phase-I dedicated detector in the order of about 10^{6} sec. The funds for COMET Phase-I has been approved as the supplemental budget, and the construction has started in 2013. The physics run is expected to start in 2018-9. The COMET Phase-II will follow immediately. In this talk, I will describe physics motivation of CLFV, and the details of COMET Phase-I / Phase-II together with the current status.

I discuss a class of weak-scale extensions of the Standard Model which is completely invisible to low-energy indirect probes. The typical signature of this scenario is the existence of new charged and/or colored states which are stable on the scale of high-energy particle detectors.

The Hagedron’s thermodynamical theory for high energy collisions has been recently extended by including Tsallis statistics. With this extension, a non-additive character was given to the so-called self-consistent thermodynamics leading to a power-law behaviour of the relevant distributions. In this talk a brief review of the extended Hagedorn’s theory will be given, and new results obtained with the nonextensive theory will be shown.

With the LHC experiments gathering more data, the exploration of the symmetry breaking sector of the Standard Model will gain renewed impetus. Likewise, it is important to search for dark matter candidates being a degree of freedom missing in the Standard Model. An invisible axion is an interesting candidate for dark matter. However trying to look for direct evidence of its existence at the LHC is hopeless as it is extremely weakly coupled. Therefore we have to resort to less direct ways to explore this sector by formulating consistent models that include the axion and deriving consequences that could be experimentally tested. In this talk we explored such consequences in the DFS model, an extension of the 2HDM with axion.

The OPERA experiment at the Gran Sasso underground laboratory has been designed to study the νμ→ντ oscillation in appearance mode in the CNGS neutrino beam. The efforts of the Collaboration to extend the analysed data sample, with five identified ντ candidates overall, and to improve the knowledge of the expected background allowed to establish the discovery of νμ→ντ oscillation with a significance larger than 5 σ. In this talk, the ντ data analysis will be discussed, with emphasis on the background constraints obtained by using dedicated data-driven control samples. The analysis of the present τ neutrino and electron neutrino samples in the framework of the 3+1 sterile model will be presented. Finally the analysis of the muon charge ratio in the cosmic ray sample will be covered.

Discrete Z_N symmetries are a common “artifact” of beyond the standard model physics models. They provide different avenues for constructing consistent scenarios for lepton and quark mixing patterns, radiative neutrino mass generation as well as dark matter stabilization. In this talk I will show how these symmetries can be derived from the spontaneous breaking of the Abelian U(1) factors contained in the global flavor symmetry transformations of the gauge invariant kinetic Lagrangian. I will show how this idea can be implemented in scenarios with right-handed neutrinos.