A. Fantini - Academia.edu (original) (raw)
Papers by A. Fantini
GDH 2004, 2005
Preliminary results on the beam asymmetry for the eta and pi° photoproduction off the quasi-free ... more Preliminary results on the beam asymmetry for the eta and pi° photoproduction off the quasi-free proton and the quasi-free neutron in the deuteron were obtained in the energy range 0.65-1.5 GeV of the incoming photon.
Polarized Sources and Targets, 2007
Frozen-spin HD targets have been used to measure beam-target double-polarization observables in p... more Frozen-spin HD targets have been used to measure beam-target double-polarization observables in pion photo-production at the LEGS (Laser Electron Gamma Source) facility. The HD targets are pure; the only unpolarizable nucleons associated with the target cell are sampled in empty-cell measurements and subtracted in the conventional way, resulting in exceptionally clean spectra. HD gas is isotopically purified by distillation and
NSTAR 2005 - Proceedings of the Workshop on the Physics of Excited Nucleons, 2006
2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000
The detection limit of invasive carcinoma by standard prone scintimammography appears to be &... more The detection limit of invasive carcinoma by standard prone scintimammography appears to be >=1 cm diameter. Since it is desirable to detect lesions at very earliest stages of growth (0.8 cm or less), the development of prototype scintimammographic systems with improved imaging performances is a primary goal. Here, the authors propose a dedicated high resolution breast imaging scanner for SPECT
Frozen-spin HD targets have been used to measure beam-target double-polarization observables in p... more Frozen-spin HD targets have been used to measure beam-target double-polarization observables in pion photo-production at the LEGS (Laser Electron Gamma Source) facility. The HD targets are pure; the only unpolarizable nucleons associated with the target cell are sampled in empty-cell measurements and subtracted in the conventional way, resulting in exceptionally clean spectra. HD gas is isotopically purified by distillation and
Electromagnetic Interactions in Nuclear and Hadron Physics - Proceedings of the International Symposium, 2002
A polarized and tagged gamma ray beam is produced at GRAAL by the Compton scattering of laser lig... more A polarized and tagged gamma ray beam is produced at GRAAL by the Compton scattering of laser light on the high energy electron circulating in the ESRF storage ring. We present results on the beam polarization asymmetries in the Compton Scattering and positive pion photo-production on proton target in the energy region 500-1500 MeV. These very precise results cover the
Nstar 2002: Proceedings of the Workshop on the Physics of Excited Nucleons, 2003
The double pi0 and omega-meson photoproduction have been measured at GRAAL. The total and differe... more The double pi0 and omega-meson photoproduction have been measured at GRAAL. The total and differential cross sections and the beam asymmetry were deduced. In the double pi0 channel, the total cross section is dominated by two peaks at 0.7 and 1.1 GeV of beam energy, the second one having been seen for the first time. The interpretation of the double
Gdh 2002: Proceedings of the Second International Symposium on the Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon, 2003
... Universitá di Trento, Italy INFN, Laboratori Nazionali di Frascati, Italy V. BELLINI Universi... more ... Universitá di Trento, Italy INFN, Laboratori Nazionali di Frascati, Italy V. BELLINI Universitá diCatania and INFN, Sezione LNS, Italy JP BOCQUET IN2P3, Institut des Sciences Nucléaire, Grenoble, France M. CASTOLDI INFN, Sezione di Genova, Italy ANNALISA D'ANGELO ...
Gdh 2002: Proceedings of the Second International Symposium on the Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon, 2003
ABSTRACT Within the GRAAL collaboration, we have constructed a Polarized HD Target Factory, impla... more ABSTRACT Within the GRAAL collaboration, we have constructed a Polarized HD Target Factory, implanted at IPN Orsay. The expected properties of the HD targets and the results already obtained for the polarization of HD samples and the relaxation times are given. New possibilities to perform GDH experiments on polarized proton, neutron and deuteron are now opened, by using the high circular polarization of the GRAAL backscattered photon beams and the large effective longitudinal polarization of the HD target, resulting essentially from its good dilution factors. Polarized total cross sections concerning the isovector Drell-Hearn Gerasimov Sum Rule related to the proton neutron difference, could be measured with minimum systematic uncertainties: the target containing both polarized protons and neutrons. An experimental method, taking advantage of the 4pi GRAAL experimental set-up is described.
Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004
Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004
The static polarization of HD samples has been achieved using ???brute force???, for HD samples p... more The static polarization of HD samples has been achieved using ???brute force???, for HD samples purified by double distillation. Proton polarization in excess of 60% and deuteron vector polarization higher than 14% have been reached. It has been demonstrated that ...
NSTAR 2004: Proceedings of the Workshop on the Physics of Excited Nucleons, 2004
Abstract: A solid, polarized HD target has been developed for the measurement of double-polarizat... more Abstract: A solid, polarized HD target has been developed for the measurement of double-polarization observables in the Δ resonance region. The focus of the experimental program is a comparison of pion photo-production amplitudes for the neutron and proton and the ...
NSTAR 2004: Proceedings of the Workshop on the Physics of Excited Nucleons, 2004
... Author(s): O. Bartalini INFN Sezione di Roma II and Università di Roma “Tor Vergata”, Italy V... more ... Author(s): O. Bartalini INFN Sezione di Roma II and Università di Roma “Tor Vergata”, Italy V. Bellini INFN Sezione di Catania and INFN Laboratori Nazionali del Sud and Università di Catania, Italy JP Bocquet IN2P3, Institut des Sciences Nucléaires, Grenoble, France M ...
International Journal of Modern Physics E, 2010
AIP Conference Proceedings, 2013
From 2000 to 2006 KLOE has collected 2.5 fb−1 of e+e− collisions at the peak of the φ(1020) and 2... more From 2000 to 2006 KLOE has collected 2.5 fb−1 of e+e− collisions at the peak of the φ(1020) and 250 pb−1 off-peak. In this paper the most recent results on meson spectroscopy are presented, with emphasis on rare eta meson decays, the search for the U boson, and γγ collisions.
International Journal of Modern Physics: Conference Series, 2014
Measurement of the difference of the decay times of neutral kaon pairs produced in an antisymmetr... more Measurement of the difference of the decay times of neutral kaon pairs produced in an antisymmetric entangled state allows for the search of possible violation of CPT symmetry and Lorentz invariance. In this paper we present the recently announced results based on the reaction ϕ → KSKL → π+π-π+π- measured at the KLOE experiment. Obtained parameters in the Standard Model Extension (SME) are: [Formula: see text]
Journal of High Energy Physics, 2013
We present a measurement of η meson production in photon-photon interactions produced by electron... more We present a measurement of η meson production in photon-photon interactions produced by electron-positron beams colliding with $ \sqrt{s}=1 $ GeV. The measurement is done with the KLOE detector at the ϕ-factory DAΦNE with an integrated luminosity of 0.24 fb−1. The e + e − → e + e − η cross section is measured without detecting the out-going electron and positron, selecting the decays η → π + π − π 0 and η → π 0 π 0 π 0. The most relevant background is due to e + e − → ηγ when the monochromatic photon escapes detection. The cross section for this process is measured as σ(e + e − → ηγ) = (856 ± 8stat ± 16syst) pb. The combined result for the e + e − → e + e − η cross section is σ(e + e − → e + e − η) = (32.72 ± 1.27stat ± 0.70syst) pb. From this we derive the partial width Γ(η → γγ) = (520 ± 20stat ± 13syst) eV. This is in agreement with the world average and is the most precise measurement to date.
Progress in Particle and Nuclear Physics, 2008
New experimental approach to study meson photoproduction in nuclei is discussed. It is based on t... more New experimental approach to study meson photoproduction in nuclei is discussed. It is based on the measurement of the recoil nucleon as a tagger for identification of the initial step of reaction. Propagation of mesons and nucleons within a nucleus is described by the Intra-Nuclear Cascade (INC) model. Simulations and preliminary experimental data for the deuteron target obtained at GRAAL are presented.
Physics Letters B, 2000
S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 5... more S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 550-1100 MeV over a wide angular range. The statistical and systematic errors of the data are much lower than in previous measurements, due to the high polarization of the photon beam and the cylindrical geometry of the 4p detector. Our results confirm the
GDH 2004, 2005
Preliminary results on the beam asymmetry for the eta and pi° photoproduction off the quasi-free ... more Preliminary results on the beam asymmetry for the eta and pi° photoproduction off the quasi-free proton and the quasi-free neutron in the deuteron were obtained in the energy range 0.65-1.5 GeV of the incoming photon.
Polarized Sources and Targets, 2007
Frozen-spin HD targets have been used to measure beam-target double-polarization observables in p... more Frozen-spin HD targets have been used to measure beam-target double-polarization observables in pion photo-production at the LEGS (Laser Electron Gamma Source) facility. The HD targets are pure; the only unpolarizable nucleons associated with the target cell are sampled in empty-cell measurements and subtracted in the conventional way, resulting in exceptionally clean spectra. HD gas is isotopically purified by distillation and
NSTAR 2005 - Proceedings of the Workshop on the Physics of Excited Nucleons, 2006
2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000
The detection limit of invasive carcinoma by standard prone scintimammography appears to be &... more The detection limit of invasive carcinoma by standard prone scintimammography appears to be >=1 cm diameter. Since it is desirable to detect lesions at very earliest stages of growth (0.8 cm or less), the development of prototype scintimammographic systems with improved imaging performances is a primary goal. Here, the authors propose a dedicated high resolution breast imaging scanner for SPECT
Frozen-spin HD targets have been used to measure beam-target double-polarization observables in p... more Frozen-spin HD targets have been used to measure beam-target double-polarization observables in pion photo-production at the LEGS (Laser Electron Gamma Source) facility. The HD targets are pure; the only unpolarizable nucleons associated with the target cell are sampled in empty-cell measurements and subtracted in the conventional way, resulting in exceptionally clean spectra. HD gas is isotopically purified by distillation and
Electromagnetic Interactions in Nuclear and Hadron Physics - Proceedings of the International Symposium, 2002
A polarized and tagged gamma ray beam is produced at GRAAL by the Compton scattering of laser lig... more A polarized and tagged gamma ray beam is produced at GRAAL by the Compton scattering of laser light on the high energy electron circulating in the ESRF storage ring. We present results on the beam polarization asymmetries in the Compton Scattering and positive pion photo-production on proton target in the energy region 500-1500 MeV. These very precise results cover the
Nstar 2002: Proceedings of the Workshop on the Physics of Excited Nucleons, 2003
The double pi0 and omega-meson photoproduction have been measured at GRAAL. The total and differe... more The double pi0 and omega-meson photoproduction have been measured at GRAAL. The total and differential cross sections and the beam asymmetry were deduced. In the double pi0 channel, the total cross section is dominated by two peaks at 0.7 and 1.1 GeV of beam energy, the second one having been seen for the first time. The interpretation of the double
Gdh 2002: Proceedings of the Second International Symposium on the Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon, 2003
... Universitá di Trento, Italy INFN, Laboratori Nazionali di Frascati, Italy V. BELLINI Universi... more ... Universitá di Trento, Italy INFN, Laboratori Nazionali di Frascati, Italy V. BELLINI Universitá diCatania and INFN, Sezione LNS, Italy JP BOCQUET IN2P3, Institut des Sciences Nucléaire, Grenoble, France M. CASTOLDI INFN, Sezione di Genova, Italy ANNALISA D'ANGELO ...
Gdh 2002: Proceedings of the Second International Symposium on the Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon, 2003
ABSTRACT Within the GRAAL collaboration, we have constructed a Polarized HD Target Factory, impla... more ABSTRACT Within the GRAAL collaboration, we have constructed a Polarized HD Target Factory, implanted at IPN Orsay. The expected properties of the HD targets and the results already obtained for the polarization of HD samples and the relaxation times are given. New possibilities to perform GDH experiments on polarized proton, neutron and deuteron are now opened, by using the high circular polarization of the GRAAL backscattered photon beams and the large effective longitudinal polarization of the HD target, resulting essentially from its good dilution factors. Polarized total cross sections concerning the isovector Drell-Hearn Gerasimov Sum Rule related to the proton neutron difference, could be measured with minimum systematic uncertainties: the target containing both polarized protons and neutrons. An experimental method, taking advantage of the 4pi GRAAL experimental set-up is described.
Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004
Nuclear Instruments & Methods in Physics Research Section a-Accelerators Spectrometers Detectors and Associated Equipment, 2004
The static polarization of HD samples has been achieved using ???brute force???, for HD samples p... more The static polarization of HD samples has been achieved using ???brute force???, for HD samples purified by double distillation. Proton polarization in excess of 60% and deuteron vector polarization higher than 14% have been reached. It has been demonstrated that ...
NSTAR 2004: Proceedings of the Workshop on the Physics of Excited Nucleons, 2004
Abstract: A solid, polarized HD target has been developed for the measurement of double-polarizat... more Abstract: A solid, polarized HD target has been developed for the measurement of double-polarization observables in the Δ resonance region. The focus of the experimental program is a comparison of pion photo-production amplitudes for the neutron and proton and the ...
NSTAR 2004: Proceedings of the Workshop on the Physics of Excited Nucleons, 2004
... Author(s): O. Bartalini INFN Sezione di Roma II and Università di Roma “Tor Vergata”, Italy V... more ... Author(s): O. Bartalini INFN Sezione di Roma II and Università di Roma “Tor Vergata”, Italy V. Bellini INFN Sezione di Catania and INFN Laboratori Nazionali del Sud and Università di Catania, Italy JP Bocquet IN2P3, Institut des Sciences Nucléaires, Grenoble, France M ...
International Journal of Modern Physics E, 2010
AIP Conference Proceedings, 2013
From 2000 to 2006 KLOE has collected 2.5 fb−1 of e+e− collisions at the peak of the φ(1020) and 2... more From 2000 to 2006 KLOE has collected 2.5 fb−1 of e+e− collisions at the peak of the φ(1020) and 250 pb−1 off-peak. In this paper the most recent results on meson spectroscopy are presented, with emphasis on rare eta meson decays, the search for the U boson, and γγ collisions.
International Journal of Modern Physics: Conference Series, 2014
Measurement of the difference of the decay times of neutral kaon pairs produced in an antisymmetr... more Measurement of the difference of the decay times of neutral kaon pairs produced in an antisymmetric entangled state allows for the search of possible violation of CPT symmetry and Lorentz invariance. In this paper we present the recently announced results based on the reaction ϕ → KSKL → π+π-π+π- measured at the KLOE experiment. Obtained parameters in the Standard Model Extension (SME) are: [Formula: see text]
Journal of High Energy Physics, 2013
We present a measurement of η meson production in photon-photon interactions produced by electron... more We present a measurement of η meson production in photon-photon interactions produced by electron-positron beams colliding with $ \sqrt{s}=1 $ GeV. The measurement is done with the KLOE detector at the ϕ-factory DAΦNE with an integrated luminosity of 0.24 fb−1. The e + e − → e + e − η cross section is measured without detecting the out-going electron and positron, selecting the decays η → π + π − π 0 and η → π 0 π 0 π 0. The most relevant background is due to e + e − → ηγ when the monochromatic photon escapes detection. The cross section for this process is measured as σ(e + e − → ηγ) = (856 ± 8stat ± 16syst) pb. The combined result for the e + e − → e + e − η cross section is σ(e + e − → e + e − η) = (32.72 ± 1.27stat ± 0.70syst) pb. From this we derive the partial width Γ(η → γγ) = (520 ± 20stat ± 13syst) eV. This is in agreement with the world average and is the most precise measurement to date.
Progress in Particle and Nuclear Physics, 2008
New experimental approach to study meson photoproduction in nuclei is discussed. It is based on t... more New experimental approach to study meson photoproduction in nuclei is discussed. It is based on the measurement of the recoil nucleon as a tagger for identification of the initial step of reaction. Propagation of mesons and nucleons within a nucleus is described by the Intra-Nuclear Cascade (INC) model. Simulations and preliminary experimental data for the deuteron target obtained at GRAAL are presented.
Physics Letters B, 2000
S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 5... more S beam asymmetries for p q photoproduction on the proton have been measured in the energy range 550-1100 MeV over a wide angular range. The statistical and systematic errors of the data are much lower than in previous measurements, due to the high polarization of the photon beam and the cylindrical geometry of the 4p detector. Our results confirm the