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The SORGENTINA-RF project aims at developing a 14 MeV fusion neutron source featuring an emission rate in the order of 5–7 × 1013 s−1. The plant relies on a metallic water-cooled rotating target and a deuterium (50%) and tritium (50%) ion beam. Beyond the main focus of medical radioisotope production, the source may represent a multi-purpose neutron facility by implementing a series of neutron-based techniques. Among the different engineering and technological issues to be addressed, the production of incondensable gases and corrosion product into the rotating target deserves a dedicated investigation. In this study, a preliminary analysis is carried out, considering the general layout of the target and the present choice of the target material.

Two topics are presented. The first one is a novel approach for a Poincare covariant description of nuclear dynamics based on light-front Hamiltonian dynamics. The key quantity is the light-front spectral function, where both normalization and momentum sum rule can be satisfied at the same time. Preliminary results are discussed for an initial analysis of the role of relativity in the EMC effect in \({{^{3}He}}\). A second issue, very challenging, is considered in a non-relativistic framework, namely a distorted spin-dependent spectral function for \({{^{3}He}}\) in order to take care of the final state interaction between the observed pion and the remnant in semi-inclusive deep inelastic electron scattering off polarized \({{^{3}He}}\). The generalization of the analysis within the light-front dynamics is outlined.

High brightness electron beam is required by several applications in the accelerator physics field. In order to have a high brightness beam, that means a high current and a low emittance beam, it is important to study, among other things, the beams non uniformity due to the non perfect transverse laser beam uniformity. Regarding the transverse analysis of the beam, statistical tools as mean and standard deviation are usually used. In this work we will show how the autocorrelation function of a photocathode laser can be used for monitoring the spatial distribution of the beam non-uniformity, strictly connected with the high electron beam emittance: we will apply our analysis on the SPARC_LAB data.

Two promising directions beyond inclusive deep inelastic scattering experiments, aimed at unveiling the three dimensional structure of the bound nucleon, are reviewed, considering in particular the $^3$He nucleus. The 3D structure in coordinate space can be accessed through deep exclusive processes, whose non-perturbative part is encoded in generalized parton distributions (GPDs). In this way, the distribution of partons in the transverse plane can be obtained. As an example, coherent deeply virtual Compton scattering (DVCS) off $^3$He nuclei, important to access the neutron GPDs, will be discussed. In Impulse Approximation (IA), the sum of two GPDs of $^3$He, $H$ and $E$, at low momentum transfer, turns out to be dominated by the neutron contribution. Besides, a technique, able to take into account the nuclear effects included in the Impulse Approximation analysis, has been developed. The spin dependent GPD $\tilde H$ of $^3$He is also found to be largely dominated, at low momentum transfer, by the neutron contribution. Semi-inclusive deep inelastic scattering processes access the momentum space 3D structure parameterized through transverse momentum dependent parton distributions. A distorted spin-dependent spectral function has been recently introduced for $^3$He, in a non-relativistic framework, to take care of the final state interaction between the observed pion and the remnant in semi-inclusive deep inelastic electron scattering off transversely polarized $^3$He. The calculation of the Sivers and Collins single spin asymmetries for $^3$He, and a straightforward procedure to effectively take into account nuclear dynamics and final state interactions, will be reviewed. The Light-front dynamics generalization of the analysis is also addressed., Comment: 10 pages, 5 figures, invited talk at the "15th Conference on Theoretical Nuclear Physics in Italy (TNPI16)", Pisa, Italy, 20-22 April 2016. To appear in the Proceedings

The possibility of improving the description of the semi-inclusive deep inelastic electron scattering off polarized 3He, that provides information on the neutron single spin asymmetries, is illustrated. In particular, the analysis at finite momentum transfers in a Poincare' covariant framework is outlined and a generalized eikonal approach to include final state interaction is presented., 4 pages, 2 figures, presented at The 22nd European Conference on Few Body Problems in Physics, Krakow, Poland, 9 - 13 September 2013

Jefferson Lab (JLab) is starting a wide experimental program aimed at studying the neutron's structure, with a great emphasis on the extraction of the parton transverse-momentum distributions (TMDs). To this end, Semi-inclusive deep-inelastic scattering (SiDIS) experiments on polarized $^3$He will be carried out, providing, together with proton and deuteron data, a sound flavor decomposition of the TMDs. Given the expected high statistical accuracy, it is crucial to disentangle nuclear and partonic degrees of freedom to get an accurate theoretical description of both initial and final states. In this contribution, a preliminary study of the Final State Interaction (FSI) in the standard SiDIS, where a pion (or a Kaon) is detected in the final state is presented, in view of constructing a realistic description of the nuclear initial and final states.

Poincar\'e covariant definitions for the spin-dependent spectral function and for the momentum distributions within the light-front Hamiltonian dynamics are proposed for a three-fermion bound system, starting from the light-front wave function of the system. The adopted approach is based on the Bakamjian--Thomas construction of the Poincar\'e generators, which allows one to easily import the familiar and wide knowledge on the nuclear interaction into a light-front framework. The proposed formalism can find useful applications in refined nuclear calculations, such as those needed for evaluating the European Muon Collaboration effect or the semi-inclusive deep inelastic cross sections with polarized nuclear targets, since remarkably the light-front unpolarized momentum distribution by definition fulfills both normalization and momentum sum rules. Also shown is a straightforward generalization of the definition of the light-front spectral function to an $A$-nucleon system.

A distorted spin-dependent spectral function for 3He is considered for the extraction of the transverse-momentum dependent parton distributions in the neutron from semi-inclusive deep inelastic electron scattering off polarized 3He at finite momentum transfers, where final state interactions are taken into account. The generalization of the analysis to a Poincar\'e covariant framework within the light-front dynamics is outlined., Comment: 4 pages, 2 figures, talk given at the 21st International Conference on Few-Body Problems in Physics, Chicago, IL, May 18th-22nd, 2015; EPJ Web of Conference, in press

We present an improved description of the semi-inclusive deep inelastic electron scattering off polarized 3 He, providing information on the neutron single spin asymmetries. The analysis at finite momentum transfers in a Poincare covariant framework is outlined and a quantitative estimate of the nuclear effects is presented.

The analysis of semi-inclusive deep inelastic electron scattering off polarized $^3$He at finite momentum transfers, aimed at the extraction of the quark transverse-momentum distributions in the neutron, requires the use of a distorted spin-dependent spectral function for $^3$He, which takes care of the final state interaction effects. This quantity is introduced in the non-relativistic case, and its generalization in a Poincar\'e covariant framework, in plane wave impulse approximation for the moment being, is outlined. Studying the light-front spin-dependent spectral function for a J=1/2 system, such as the nucleon, it is found that, within the light-front dynamics with a fixed number of constituents and in the valence approximation, only three of the six leading twist T-even transverse-momentum distributions are independent., Comment: 6 pages, 1 figure, invited talk at the Conference "Light Cone 2014 (LC2014)", Raleigh, North Carolina, May 26-30, 2014. Submitted to Few-Body Systems

The possibility to extract the quark transverse-momentum distributions in the neutron from semi-inclusive deep inelastic electron scattering off polarized 3He is illustrated through an impulse approximation analysis in the Bjorken limit. The generalization of the analysis at finite momentum transfers in a Poincare' covariant framework is outlined. The definition of the light-front spin-dependent spectral function of a J=1/2 system allows us to show that within the light-front dynamics only three of the six leading twist T-even transverse-momentum distributions are independent., Comment: 4 pages, 2 figures, Presented at the 20th International IUPAP Conference on Few-Body Problems in Physics, 20 - 25 August, 2012, Fukuoka, Japan

A distorted spin-dependent spectral function for 3 He is considered to take care of the final state interaction in the extraction of the quark transverse-momentum distributions in the neutron from semi-inclusive deep inelastic electron scattering off polarized 3 He at finite momentum transfers. The generalization of the analysis in a Poincare covariant framework within the light-front dynamics is outlined. The definition of the light-front spin-dependent spectral function for a J=1/2 system, as the nucleon, allows us to show that within the light-front dynamics and in the valence approximation only three of the six leading twist T-even transverse- momentum distributions are independent.

Through an impulse approximation analysis of single spin Sivers and Collins asymmetries in the Bjorken limit, the possibility to extract the quark transverse-momentum distributions in the neutron from semi-inclu- sive deep inelastic electron scattering off polarized 3He is illustrated. The analysis is generalized to finite momentum transfers in a light-front Poincare covariant framework, defining the light-front spin-dependent spectral func- tion of a J = 1/2 system. The definition of the light-front spin-dependent spectral function for constituent quarks in the nucleon allows us to show that, within the light-front dynamics, only three of the six leading twist T-even transverse-momentum distributions are independent.

The extended and precise investigation of the nucleon (spin) structure is a cornerstone of the EIC initiative; the availability of deuteron and $^3$He polarized beams will offer unprecedented opportunities to obtain information on the neutron spin structure comparable to those of the proton; the combination of these data will allow to deepen knowledge and understanding of many aspects of the nucleon spin physics: from a more precise test of the Bjorken sum rule to a more detailed picture of the flavor structure of the nucleon sea, as well as a precise determination of different spin and transverse momentum dependent functions, at leading and higher twists. Moreover, almost close kinematics and large acceptance detectors typical of a collider, will potentially offer new measurement perspectives beyond the asymmetries.

Semi-inclusive deep inelastic electron scattering off polarized 3He is studied in a non-relativistic framework, using a distorted spin-dependent spectral function for 3He to take care of the final state interaction between the observed pion and the remnant. A simple procedure is shown to be valuable for the extraction of Sivers and Collins asymmetries for the neutron fromthe corresponding asymmetries for 3He. To extend this study in a relativistic framework, a novel approach for a Poincar\'e covariant description of nuclear dynamics is presented, based on the light-front Hamiltonian dynamics. The key quantity is the light-front spectral function, where both normalization and momentum sum rule can be satisfied at the same time. Preliminary results are discussed for an initial analysis of the role of relativity in the EMC effect in 3He, and the generalization of the procedure for the extraction of neutron asymmetries within the light-front dynamics is outlined., Comment: Pages 8, figures 3. Talk given at the 26th International Nuclear Physics Conference, 11-16 September, 2016, Adelaide, Australia, to be published in Proceedings of Science. Comments added. arXiv admin note: text overlap with arXiv:1602.06521