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Neutrinos are among the most abundant particles in the universe, nearly massless, travel at speeds near the speed of light and are electrically neutral. Neutrinos can be generated through man-made sources like particle accelerators or by natural sources like the sun. Neutrinos only interact via the weak force and gravity. Since gravitational interaction is extremely weak and the weak force has a very short range, neutrinos can travel long distances unimpeded through matter, reaching places inaccessible to GNSS (Global Navigation Satellite System) signals such as underwater locations. The main objective of this work is to sketch an early high-level design of a Neutrino PNT (Position, Navigation and Timing) mission and analyze its feasibility for submarine navigation since there is a need to improve current navigation technologies for submarines. The high-level preliminary concept proposes Cyclotrons or Linear Accelerators based on the physical process Pion Decay at Rest as neutrino sources. For detecting such isotropic neutrino fluxes user equipment must be composed of a high-performance clock synchronized with the system, a detector and possibly additional sensors such as IMU (Inertial Measurement Unit). A feasibility analysis of the recommended system option is performed based on simulations for determining the neutrino detection rate and on a PNT tool to estimate the PNT performances. Although the submarine navigation application is in the limit of being feasible with current technology, it could be realized with some important but reasonable progress in source and neutrino detector technology., Comment: 10pages, 12 figures

The recent formulation of the factorization theorem for transverse momentum spectra in terms of well-defined transverse momentum dependent distributions (TMDs), allows for a better understanding of the role of the perturbative and non-perturbative QCD contributions and their interplay. In particular, non-perturbative effects are often included both in the evolution of the TMDs and in the modeling of their scale-independent part. Using the available Drell-Yan and $Z$-production data at low and high energy we show that, for the currently available dilepton invariant mass values, the TMD evolution is driven mainly by its perturbative contribution, while the needed non-perturbative correction is scale independent. We then detail the difference between the scale dependences in the high and low boson transverse momentum regime and discuss the related theoretical errors., Comment: 11 pages, Proceeding of CIPANP2015

We present a review of current Transverse Momentum Dependent (TMD) phenomenology focusing our attention on the unpolarized TMD parton distribution function and the Sivers function. The paper introduces and comments about the new Collins-Soper-Sterman (CSS) TMD evolution formalism. We make use of a selection of results obtained by several groups to illustrate the achievements and the failures of the simple Gaussian approach and the TMD CSS evolution formalism., Comment: 10 pages, 5 figures, to appear in the proceedings of the TRANSVERSITY 2014, Chia, Italy, 9-13 June, 2014

The factorization theorem for $q_T$ spectra in Drell-Yan processes, boson production and semi-inclusive deep inelastic scattering allows for the determination of the non-perturbative parts of transverse momentum dependent parton distribution functions. Here we discuss the fit of Drell-Yan and $Z$-production data using the transverse momentum dependent formalism and the resummation of the evolution kernel. We find a good theoretical stability of the results and a final $\chi^2/{\rm points}\lesssim 1$. We show how the fixing of the non-perturbative pieces of the evolution can be used to make predictions at present and future colliders., Comment: 6 pages, 3 pdf figures, uses webofc.cls. Invited talk delivered by I. Scimemi at the Fourth International Workshop on "Transverse Polarisation Phenomena in Hard Processes" (Transversity 2014), Chia, Cagliari, Italy, June 9-13, 2014. To appear in EPJ Web of Conferences

The factorization theorems for transverse momentum distributions of dilepton/boson production, recently formulated by Collins and Echevarria-Idilbi-Scimemi in terms of well-defined transverse momentum dependent distributions (TMDs), allows for a systematic and quantitative analysis of non-perturbative QCD effects of the cross sections involving these quantities. In this paper we perform a global fit using all current available data for Drell-Yan and $Z$-boson production at hadron colliders within this framework. The perturbative calculable pieces of our estimates are included using a complete resummation at next-to-next-to-leading-logarithmic accuracy. Performing the matching of transverse momentum distributions onto the standard collinear parton distribution functions and recalling that the corresponding matching coefficient can be partially exponentiated, we find that this exponentiated part is spin-independent and resummable. We argue that the inclusion of higher order perturbative pieces is necessary when data from lower energy scales are analyzed. We consider non-perturbative corrections both to the intrinsic nucleon structure and to the evolution kernel and find that the non-perturbative part of the TMDs could be parametrized in terms of a minimal set of parameters (namely 2-3). When all corrections are included the global fit so performed gives a $\chi^2/{\rm d.o.f.} \lesssim 1$ and a very precise prediction for vector boson production at the Large Hadron Collider (LHC)., Comment: 24 pages, 11 figures. v2: new subsection added, discussion on the stability of the calculations and on higher order contributions improved, results unchanged

Using a previous extraction of the quark Boer-Mulders distributions from semiinclusive deep inelastic scattering data, we fit the unpolarized Drell-Yan data on the $\cos 2 \phi$ asymmetry, determining the antiquark Boer-Mulders distributions. A good agreement with the data is found in the region of low $q_T$, where the transverse-momentum factorization approach applies., Comment: 7 pages, 3 figures

We present a phenomenological analysis of the $\cos 2 \phi$ asymmetry recently measured by the COMPASS and HERMES collaborations in unpolarized semi-inclusive deep inelastic scattering. In the kinematical regimes explored by these experiments the asymmetry arises from transverse-spin and intrinsic transverse-momentum effects. We consider the leading-twist contribution, related to the so-called Boer-Mulders transverse-polarization distribution $h_1^{\perp}(x, k_T^2)$, and the twist-4 Cahn contribution, involving unpolarized transverse-momentum distribution functions. We show that a reasonably good fit of the data is achieved with a Boer-Mulders function consistent with the main theoretical expectations. Our conclusion is that the COMPASS and HERMES measurements represent the first experimental evidence of the Boer-Mulders effect in SIDIS., Comment: 11 pages, 7 figures, published version in PRD