M. Contalbrigo
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Advanced NMR Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Neutrino Physics Research
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Astrophysics and Cosmic Phenomena
- Atomic and Molecular Physics
- Physics of Superconductivity and Magnetism
- Superconductivity in MgB2 and Alloys
- Muon and positron interactions and applications
- Quantum, superfluid, helium dynamics
- Pulsars and Gravitational Waves Research
- Medical Imaging Techniques and Applications
- Computational Physics and Python Applications
- Magnetic confinement fusion research
- Inorganic Fluorides and Related Compounds
Istituto Nazionale di Fisica Nucleare, Sezione di Genova
2012-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara
2015-2024
University of Ferrara
2011-2023
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2023
Thomas Jefferson National Accelerator Facility
2011-2022
SLAC National Accelerator Laboratory
2022
University of York
2020-2021
Istituto Nazionale di Fisica Nucleare
2003-2020
Duquesne University
2020
Istituto Nazionale di Fisica Nucleare, Laboratori Acceleratori e Superconduttività Applicata
2019
Single-spin asymmetries for semi-inclusive electroproduction of charged pions in deep-inelastic scattering positrons are measured the first time with transverse target polarization. The asymmetry depends on azimuthal angles both pion ($\ensuremath{\phi}$) and spin axis (${\ensuremath{\phi}}_{S}$) about virtual-photon direction relative to lepton plane. extracted Fourier component $\mathbf{⟨}\mathrm{sin}(\ensuremath{\phi}+{\ensuremath{\phi}}_{S}){\mathbf{⟩}}_{UT}^{\ensuremath{\pi}}$ is a...
Precise measurements of the spin structure functions proton ${g}_{1}^{p}(x,{Q}^{2})$ and deuteron ${g}_{1}^{d}(x,{Q}^{2})$ are presented over kinematic range $0.0041\ensuremath{\le}x\ensuremath{\le}0.9$ $0.18\text{ }\text{ }{\mathrm{GeV}}^{2}\ensuremath{\le}{Q}^{2}\ensuremath{\le}20\text{ }{\mathrm{GeV}}^{2}$. The data were collected at HERMES experiment DESY, in deep-inelastic scattering 27.6 GeV longitudinally polarized positrons off hydrogen deuterium gas targets internal to HERA storage...
Azimuthal single-spin asymmetries of lepto-produced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from non-vanishing Sivers effects pi+, pi0, K+, K-, as well in the difference pi+ pi- cross sections.
Polarized deep-inelastic scattering data on longitudinally polarized hydrogen and deuterium targets have been used to determine double-spin asymmetries of cross sections. Inclusive semi-inclusive for the production positive negative pions from were obtained in a reanalysis previously published data. kaons measured target. The separate helicity densities up down quarks anti-up, anti-down, strange sea computed these “leading order” QCD analysis. polarization up-quark is that down-quark...
We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions (ν μ n→μ − p $\bar{\nu }_{\mu}p\to\mu^{+}n$ ) using a set of experimental data collected by NOMAD Collaboration. performed measurements cross-section these processes on nuclear target (mainly carbon) normalizing it to total ν ( $\bar{\nu}_{\mu}$ charged-current cross section. The results for flux-averaged QEL sections in (anti)neutrino energy interval 3–100 GeV are $\langle...
We present the results of a search for νμ→νe oscillations in NOMAD experiment at CERN. The looked appearance νe predominantly νμ wide-band neutrino beam CERN SPS. No evidence was found. 90% confidence limits obtained are Δm2<0.4 eV2 maximal mixing and sin2(2θ)<1.4×10−3 large Δm2. This result excludes LSND allowed region oscillation parameters with Δm2≳10 eV2.
Single-spin asymmetries for pions and charged kaons are measured in semi-inclusive deep-inelastic scattering of positrons electrons off a transversely nuclear-polarized hydrogen target. The dependence the cross section on azimuthal angles target polarization (phi_S)and produced hadron (phi) is found to have substantial sin(phi+phi_S) modulation production pi+, pi- K+. This Fourier component can be interpreted terms non-zero transversity distribution functions favored disfavored Collins...
Multiplicities in semi-inclusive deep-inelastic scattering are presented for each charge state of ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ and ${\mathrm{K}}^{\ifmmode\pm\else\textpm\fi{}}$ mesons. The data were collected by the HERMES experiment at HERA storage ring using 27.6 GeV electron positron beams incident on a hydrogen or deuterium gas target. results as function kinematic quantities ${x}_{\mathrm{B}}$, ${Q}^{2}$, $z$, ${P}_{h\ensuremath{\perp}}$. They represent unique set...
The transition helicity amplitudes from the proton ground state to $P_{11}(1440)$ and $D_{13}(1520)$ excited states ($\gamma_{v}pN^*$ electrocouplings) were determined analysis of nine independent one-fold differential $\pi^{+} \pi^{-} p$ electroproduction cross sections off a target, taken with CLAS at photon virtualities 0.25\enskip {\rm GeV$^{2}$} $<$ $Q^{2}$ 0.60 \enskip GeV$^{2}$}. phenomenological reaction model was employed for separation resonant non-resonant contributions final...
We measured the triple coincidence A(e,e'np) and A(e,e'pp) reactions on carbon, aluminum, iron, lead targets at Q2 > 1.5 (GeV/c)2, xB 1.1 missing momentum 400 MeV/c. This was first direct measurement of both proton-proton (pp) neutron-proton (np) short-range correlated (SRC) pair knockout from heavy asymmetric nuclei. For all nuclei, average to reduced cross-section ratio is about 6%, in agreement with previous indirect measurements. Correcting for Single-Charge Exchange effects decreased...
Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using CLAS detector 5.75-GeV polarized electron beam of Jefferson Lab accelerator, 110 (Q^{2},x_{B},t) bins over widest phase space ever explored in valence-quark region. Several models generalized parton distributions (GPDs) describe data well at most our kinematics. This increases confidence that we understand GPD H, expected to be dominant contributor these...
There is a significant discrepancy between the values of proton electric form factor, G(E)(p), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect extraction G(E)(p) from electron-proton cross sections. We determined TPE contribution by measuring ratio positron-proton to elastic scattering sections simultaneous, tertiary electron-positron beam incident on liquid hydrogen target...
The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, direct measure contribution hard two-photon exchange section. In measurement, 2.01 GeV electron and positron beams were directed through hydrogen gas target internal DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers time-of-flight scintillators detected elastically scattered leptons in coincidence recoiling...
The momentum and helicity density distributions of the strange quark sea in nucleon are obtained leading order from charged-kaon production deep-inelastic scattering on deuteron. extracted spin-averaged K+/- multiplicities, inclusive double-spin asymmetries for polarized positrons by a deuterium target. shape distribution is softer than that average ubar dbar quarks. In region measurement 0.02 < x 0.6 Q^2 > 1.0 GeV^2, zero within experimental uncertainties.