L. Ciciani
A5037654682- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Radioactivity and Radon Measurements
- Radioactive contamination and transfer
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Advanced NMR Techniques and Applications
- Nuclear and radioactivity studies
- Superconducting Materials and Applications
- Graphite, nuclear technology, radiation studies
- Radiation Detection and Scintillator Technologies
- Nuclear Physics and Applications
- Inorganic Fluorides and Related Compounds
- Electron Spin Resonance Studies
- Scientific Research and Discoveries
- Advanced Semiconductor Detectors and Materials
- Nuclear Materials and Properties
- Particle Detector Development and Performance
- Magnetism in coordination complexes
- Radiation Therapy and Dosimetry
- Magnetic properties of thin films
- Earthquake Detection and Analysis
- Spacecraft and Cryogenic Technologies
- Atomic and Molecular Physics
National Agency for New Technologies, Energy and Sustainable Economic Development
2021-2023
ENEA Casaccia Research Centre
2023
Imperial College London
2003-2007
Old Dominion University
2001-2004
Massachusetts Institute of Technology
2004
Thomas Jefferson National Accelerator Facility
2004
Campbell Collaboration
2004
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
1998-2000
Institut de Physique
1999
Institut National de Physique Nucléaire et de Physique des Particules
1999
In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to exotic baryon with strangeness S=+1 is seen in K(+)n invariant mass spectrum. The at 1.542+/-0.005 GeV/c(2) measured width 0.021 FWHM, which largely determined by experimental resolution. statistical significance (5.2+/-0.6)sigma. and observed are consistent recent reports other groups.
We report the first results of beam-spin asymmetry measured in reaction $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}\mathrm{ep}\ensuremath{\gamma}$ at a beam energy 4.25 GeV. A large with $\mathrm{sin}\ensuremath{\varphi}$ modulation is observed, as predicted for interference term deeply virtual compton scattering (DVCS) and Bethe-Heitler process. The amplitude this...
The reaction gamma p-->pi(+)K(-)K(+)n was studied at Jefferson Laboratory using a tagged photon beam with an energy range of 3-5.47 GeV. A narrow baryon state strangeness S=+1 and mass M=1555+/-10 MeV/c(2) observed in the nK(+) invariant spectrum. peak's width is consistent CLAS resolution (FWHM=26 MeV/c(2)), its statistical significance (7.8+/-1.0)sigma. positive has exotic structure cannot be described framework naive constituent quark model. predicted by chiral soliton model for Theta(+)...
Cross-sections and recoil polarizations for the reactions gamma + p --> K^+ Lambda Sigma^0 have been measured with high statistics good angular coverage center-of-mass energies between 1.6 2.3 GeV. In K^+Lambda channel we confirm a structure near W=1.9 GeV at backward kaon angles, but our data shows more complex s- u- resonance than previously seen. This is present forward angles not central its position width change angle, indicating that one playing role. Rising back-angle cross sections...
The ratios of inclusive electron scattering cross sections $^4$He, $^{12}$C, and $^{56}$Fe to $^3$He have been measured for the first time. It is shown that these are independent $x_B$ at Q$^2>$1.4 (GeV/c)$^2$ $x_B>$ 1.5 where section depends primarily on high-momentum components nuclear wave function. observed scaling shows momentum distributions high-momenta same shape all nuclei differ only by a scale factor. onset $x_B >$1.5 consistent with kinematical expectation two nucleon short range...
We report the first evidence for a nonzero beam-spin azimuthal asymmetry in electroproduction of positive pions deep-inelastic kinematic region. Data reaction $e\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{'}}{\ensuremath{\pi}}^{+}X$ have been obtained using polarized electron beam 4.3 GeV with CEBAF Large Acceptance Spectrometer at Thomas Jefferson National Accelerator Facility. The amplitude $\mathrm{sin}\ensuremath{\varphi}$ modulation increases momentum pion relative to virtual...
We present new $\ensuremath{\Sigma}$ beam asymmetry data for $\ensuremath{\eta}$ meson photoproduction on the proton, using a novel tagged, laser backscattered, linearly polarized photon up to 1.1 GeV. The show large, positive asymmetries, at all incident energies. In addition ${S}_{11}(1535)$ and ${D}_{13}(1520)$ resonances necessary reproduce cross sections, ${P}_{13}(1720)$ ${D}_{15}(1675)$ ``four stars'' contribute observable, but cannot strong forward asymmetries measured energies...
The cross section for the reaction ep-->e(')ppi(+)pi(-) was measured in resonance region 1.4<W<2.1 GeV and 0.5<Q2<1.5 GeV(2)/c(2) using CLAS detector at Jefferson Laboratory. data show resonant structures not visible previous experiments. comparison of our to a phenomenological prediction available information on N(*) Delta states shows an evident discrepancy. A better description is obtained either by sizable change properties P13(1720) or introducing new baryon state, reported published analyses.
Double-polarization asymmetries for inclusive ep scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a NH3 target in the CLAS detector. The structure function g(1)(x,Q2) was extracted throughout nucleon resonance region into deep inelastic regime, Q(2)=0.15-1.64 GeV2. contributions to first moment Gamma(1)(Q2)= integral dx determined up Q(2)=1.2 Using parametrization g(1) unmeasured low x regions, complete estimated over this Q2...
Received 21 January 2004DOI:https://doi.org/10.1103/PhysRevLett.92.049902©2004 American Physical Society
We measured the inclusive electron-proton cross section in nucleon resonance region $(W<2.5\mathrm{GeV})$ at momentum transfers ${Q}^{2}$ below $4.5(\mathrm{GeV}{/c)}^{2}$ with CLAS detector. The large acceptance of allowed measurement a large, contiguous two-dimensional range and x, making it possible to perform an integration data fixed over significant x interval. From these we extracted structure function ${F}_{2}$ and, by including other world data, studied evolution its moments,...
The first measurements of the transferred polarization for exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using CLAS spectrometer. A 2.567 GeV beam was used to measure hyperon over Q2 from 0.3 1.5 (GeV/c)(2), W 1.6 2.15 GeV, and full K+ center-of-mass angular range. Comparison with predictions hadrodynamic models indicates strong sensitivity underlying resonance contributions. nonrelativistic quark-model interpretation our data suggests that ssmacr;...
The polarized longitudinal-transverse structure function σLT′ has been measured in the Δ(1232) resonance region at Q2=0.40 and 0.65GeV2. Data for p(→e,e′p)π0 reaction were taken Jefferson Lab with CEBAF large acceptance spectrometer (CLAS) using longitudinally electrons an energy of 1.515 GeV. For first time a complete angular distribution was measured, permitting separation different nonresonant amplitudes partial wave analysis. Comparison previous beam asymmetry measurements MAMI indicate...
The polarized longitudinal-transverse structure function σLT′ has been measured using the p(e⃗,e′π+)n reaction in Δ(1232) resonance region at Q2=0.40 and 0.65GeV2. No previous data exist for this channel. kinematically complete experiment was performed Jefferson Lab with CEBAF large acceptance spectrometer longitudinally electrons an energy of 1.515GeV. A partial-wave analysis shows generally better agreement recent phenomenological models pion electroproduction compared to previously π0p...
We report the results of a new measurement spin structure functions deuteron in region moderate momentum transfer ($Q^2$ = 0.27 -- 1.3 (GeV/c)$^2$) and final hadronic state mass nucleon resonance ($W$ 1.08 2.0 GeV). scattered 2.5 GeV polarized continuous electron beam at Jefferson Lab off dynamically cryogenic solid target ($^{15}$ND$_3$) detected electrons with CEBAF Large Acceptance Spectrometer (CLAS). From our data, we extract longitudinal double asymmetry $A_{||}$ function $g_1^d$. Our...
We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic range. The kinetic energy distribution for "fast" nucleons (p>250 MeV/c) peaks where two each 20% or less, and third nucleon has most of transferred energy. These fast pp pn pairs are back to with little momentum along three-momentum transfer, indicating that they spectators. Calculations by Sargsian Laget also indicate we distorted two-nucleon distributions striking one detecting spectator correlated pair.
Gamma emitting radionuclides naturally present in the Earth’s crust and radon exhaled by soil atmosphere with its short-lived progeny are two of main contributors to environmental gamma dose rate that typically characterizes an outdoor measurement site. The work aims investigate variations dose-rate time series originated different natural phenomena, such as weather seismic events, which can modify concentration air. data analyzed here were acquired over a five-year period using...
The reaction $e\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{'}}{K}^{+}\ensuremath{\Lambda}(1520)$ with $\ensuremath{\Lambda}(1520)\ensuremath{\rightarrow}{p}^{\ensuremath{'}}{K}^{\ensuremath{-}}$ was studied at electron beam energies of 4.05, 4.25, and 4.46 GeV, using the CLAS detector Thomas Jefferson National Accelerator Facility. $\mathrm{cos}{\ensuremath{\theta}}_{{K}^{+}},$ ${\ensuremath{\varphi}}_{{K}^{+}},$ ${Q}^{2},$ W dependencies $\ensuremath{\Lambda}(1520)$...
Measurements of the angular distributions target and double spin asymmetries for Delta(1232) in exclusive channel (polarized-p polarized-e,e-prime p)pi0 obtained at Jefferson Lab Q2 range from 0.5 to 1.5 gev2 are presented. Results compared with unitary isobar model, dynamical models, effective Lagrangian theory. Sensitivity different models was observed, particularly relation description background terms on which asymmetry depends significantly.
The double spin asymmetry in the $\vec{e}\vec{p}\to e' \pi^+ n$ reaction has been measured for first time resonance region four-momentum transfer $Q^2=0.35-1.5$ GeV$^2$. Data were taken at Jefferson Lab with CLAS detector using a 2.6 GeV polarized electron beam incident on solid NH$_3$ target. Comparison predictions of phenomenological models shows strong sensitivity to contributions. Helicity-1/2 transitions are found be dominant second and third regions. is consistent faster rise $Q^2$...
Abstract Future manned missions in deep space toward Moon and Mars represent one of the greatest challenges for radiological protection, which task is to mitigate risks human life raised by hostile radiation environment. The prolonged exposure astronauts cosmic rays, mainly ion fields galactic or solar origin, with a large dynamical behavior time wide range kinetic energies, may result an unacceptable risk next missions. Indeed, these ions can deliver significant doses directly hitting...
We studied the exclusive reaction e p --> e' p' phi using K^+ K^- decay mode. The data were collected a 4.2 GeV incident electron beam and CLAS detector at Jefferson Lab. Our experiment covers range in Q^2 from 0.7 to 2.2 GeV^2, W 2.0 2.6 GeV. Taken together with all previous data, we find consistent picture of production on proton. measurement shows expected decrease t-slope vector meson formation time c Delta tau below 2 fm. At = 0.6 fm, measure b_phi 2.27 +- 0.42 GeV^-2. cross section...