0000000001299224

AUTHOR

G. Caselotti

showing 19 related works from this author

Compton scattering from the free and bound proton at backward angles above π-threshold

1999

Differential cross sections for Compton scattering from the free proton at Theta(gamma)(lab) = 130.7 degrees in the energy region from 200 MeV to 410 MeV and far quasi-free Compton scattering from the proton bound in the deuteron at Theta(gamma)(lab) = 148.8 degrees in the energy region from 200 MeV to 290 MeV have been measured. The free proton data are in agreement with dispersion-theory predictions based on standard parameters. The difference of the proton polarizabilities has been extracted from the quasi-free data. Our result, - = [9.1 +/- 1.7(stat + syst) +/- 1.2(mod)] x 10(-4) fm(3), is in reasonable agreement with the world average of the free proton data if the backward spin polari…

PhysicsNuclear and High Energy PhysicsBackscatterProton010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaNuclear TheoryCompton scattering01 natural sciencesNuclear physicsDeuteriumPolarizabilityDispersion relation0103 physical sciencesNeutronAtomic physicsNuclear Experiment010306 general physicsSpin-½
researchProduct

Quasi-free Compton Scattering and the Polarizabilities of the Neutron

2002

Differential cross sections for quasi-free Compton scattering from the proton and neutron bound in the deuteron have been measured using the Glasgow/Mainz tagging spectrometer at the Mainz MAMI accelerator together with the Mainz 48 cm $\oslash$ $\times$ 64 cm NaI(Tl) photon detector and the G\"ottingen SENECA recoil detector. The data cover photon energies ranging from 200 MeV to 400 MeV at $\theta^{LAB}_\gamma=136.2^\circ$. Liquid deuterium and hydrogen targets allowed direct comparison of free and quasi-free scattering from the proton. The neutron detection efficiency of the SENECA detector was measured via the reaction $p(\gamma,\pi^+ n)$. The "free" proton Compton scattering cross sect…

Nuclear and High Energy PhysicsProtonNuclear TheoryFOS: Physical sciences7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)High Energy Physics - Phenomenology (hep-ph)Polarizability0103 physical sciencesNeutron detectionNeutronNuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentNuclear ExperimentPhysics010308 nuclear & particles physicsScatteringCompton scatteringHigh Energy Physics - PhenomenologyDeuteriumCover (topology)High Energy Physics::Experiment
researchProduct

In-medium modifications of the pi pi interaction in photon-induced reactions

2002

Differential cross sections of the reactions $(\gamma,\pi^\circ\pi^\circ)$ and $(\gamma,\pi^\circ\pi^++\pi^\circ\pi^-)$ have been measured for several nuclei ($^1$H,$^{12}$C, and $^{\rm nat}$Pb) at an incident-photon energy of $E_{\gamma}$=400-460 MeV at the tagged-photon facility at MAMI-B using the TAPS spectrometer. A significant nuclear-mass dependence of the $\pi\pi$ invariant-mass distribution is found in the $\pi^\circ\pi^\circ$ channel. This dependence is not observed in the $\pi^\circ\pi^{+/-}$ channel and is consistent with an in-medium modification of the $\pi\pi$ interaction in the $I$=$J$=0 channel. The data are compared to $\pi$-induced measurements and to calculations within …

PhysicsPhotonMesonPAIRSHadronCarbon-12General Physics and AstronomyElementary particleNONPERTURBATIVE APPROACHCHIRAL-SYMMETRY RESTORATIONPionNUCLEAR MEDIUMPiSPECTROMETERMESONAtomic physicsNuclear ExperimentNuclear ExperimentMATTERBoson
researchProduct

Neutron polarizabilities investigated by quasi-free Compton scattering from the deuteron

2002

Measuring Compton scattered photons and recoil neutrons in coincidence, quasifree Compton scattering by the neutron has been investigated at MAMI (Mainz) at ${\ensuremath{\theta}}_{\ensuremath{\gamma}}^{\mathrm{lab}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}136\ifmmode^\circ\else\textdegree\fi{}$ in an energy range from 200 to 400 MeV. From the data a polarizability difference of ${\ensuremath{\alpha}}_{n}\ensuremath{-}{\ensuremath{\beta}}_{n}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}9.8\ifmmode\pm\else\textpm\fi{}3.6(\mathrm{stat}{)}_{\ensuremath{-}1.1}^{+2.1}(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}2.2(\mathrm{model})$ in units of ${10}^{\ensuremath{-}4}{\mathrm{fm}}^{…

Physics010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaCompton scatteringGeneral Physics and AstronomyFOS: Physical sciencesAstrophysics::Cosmology and Extragalactic Astrophysics7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentHigh Energy Physics - PhenomenologyHigh Energy Physics - Experiment (hep-ex)High Energy Physics - Phenomenology (hep-ph)Deuterium0103 physical sciencesNeutronHigh Energy Physics::ExperimentAtomic physicsNuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentNuclear ExperimentEnergy (signal processing)Astrophysics::Galaxy Astrophysics
researchProduct

Backward spin polarizabilityγπof the proton

2002

Using the Mainz $48\mathrm{cm}\ensuremath{\emptyset}\ifmmode\times\else\texttimes\fi{}64\mathrm{cm}$ NaI(Tl) detector and the segmented G\"ottingen recoil detector SENECA in coincidence, Compton scattering by the proton at ${\ensuremath{\theta}}_{\ensuremath{\gamma}}^{\mathrm{lab}}=136\ifmmode^\circ\else\textdegree\fi{}$ has been measured at MAMI (Mainz) in the energy range from 200 to 470 MeV. The new data confirm the previous observation that there is a systematic discrepancy between MAMI and LEGS (Brookhaven) data leading to different spin polarizabilities ${\ensuremath{\gamma}}_{\ensuremath{\pi}}=\ensuremath{-}38.7\ifmmode\pm\else\textpm\fi{}1.8$ and $\ensuremath{-}27.2\ifmmode\pm\else\…

Elastic scatteringPhysicsNuclear and High Energy PhysicsParticle physicsProton010308 nuclear & particles physicsHadronElementary particle01 natural sciencesOrientation (vector space)Nuclear physicsBaryon0103 physical sciences010306 general physicsNucleonEnergy (signal processing)Physical Review C
researchProduct

Compton scattering from the free and bound proton above π-threshold

2000

The differential cross sections for Compton scattering from the proton have been measured at MAMI with three different detector setups. There is a good agreement among all the results. The theoretical calculation based on dispersion relations shows that there is no drastic change necessary in the parameters of this approach.

PhysicsNuclear and High Energy PhysicsProton010308 nuclear & particles physicsDetectorCompton scatteringCompton wavelengthInelastic scattering01 natural sciencesNuclear physicsDispersion relation0103 physical sciencesNuclear Experiment010306 general physics
researchProduct

The Reactionγp→π0γ′pand the Magnetic Dipole Moment of theΔ+(1232)Resonance

2002

The reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\gamma}}^{\ensuremath{'}}p$ has been measured with the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for energies between $\sqrt{s}=1221--1331\text{ }\text{ }\mathrm{M}\mathrm{e}\mathrm{V}$. The cross section's differential in angle and energy have been determined for the photon ${\ensuremath{\gamma}}^{\ensuremath{'}}$ in three bins of the excitation energy. This reaction channel provides access to the magnetic dipole moment of the ${\ensuremath{\Delta}}^{+}(1232)$ resonance and, for the first time, a value of ${\ensuremath{\mu}}_{{\ensuremath{\Delta}}^{+}}=\mathbf{[}{2.7}_{\ensu…

BaryonPhysicsCrystallographyParticle physicsAngular distributionMagnetic momentPiGeneral Physics and AstronomyResonanceNuclear ExperimentEnergy (signal processing)Physical Review Letters
researchProduct

"Table 6" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI+/- production with a Lead target. Errors are statistical only.

Single Differential Cross SectionPhotoproductionDSIG/DMGAMMA PB --> PI0 PI+GAMMA PB --> PI0 PI-ExclusiveGAMMA NUCLEUS --> PI- PI0GAMMA NUCLEUS --> PI+ PI0
researchProduct

"Table 2" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI0 production with a Carbon target. Errors are statistical only.

GAMMA NUCLEUS --> PI0 PI0Single Differential Cross SectionPhotoproductionDSIG/DMGAMMA C --> PI0 PI0Exclusive
researchProduct

"Table 1" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI0 production with a proton target. Errors are statistical only. Note that the data given in this table are sightly different (newer) than the data points presented in the paper.

Single Differential Cross SectionGAMMA P --> PI0 PI0PhotoproductionDSIG/DMExclusive1.277-1.32
researchProduct

"Table 4" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI+ production with a proton target. Errors are statistical only. Note that the data given in this table are sightly different (newer) than the data points presented in the paper.

Single Differential Cross SectionPhotoproductionDSIG/DMExclusiveGAMMA P --> PI0 PI+1.277-1.32
researchProduct

"Table 3" of "Quasi-free Compton Scattering and the Polarizabilities of the Neutron"

2003

Energy dependence of the triple differential cross section w.r.t. the scattered proton.

PhotoproductionTriple Differential Cross SectionExclusiveGAMMA DEUT --> GAMMA P NNuclear ExperimentD3SIG/DE/DOMEGA/DOMEGA
researchProduct

"Table 3" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI0 production with a Lead target. Errors are statistical only.

GAMMA NUCLEUS --> PI0 PI0Single Differential Cross SectionPhotoproductionDSIG/DMExclusiveGAMMA PB --> PI0 PI0
researchProduct

"Table 1" of "Compton scattering from the free and bound proton at backward angles above pi threshold."

2000

No description provided.

Single Differential Cross SectionPhotoproduction1.12-1.284GAMMA P --> P GAMMAExclusiveDSIG/DOMEGA
researchProduct

"Table 2" of "Quasi-free Compton Scattering and the Polarizabilities of the Neutron"

2003

Energy dependence of the quasi-free proton differential cross section.

Single Differential Cross SectionPhotoproduction1.146-1.266ElasticNuclear TheoryPhysics::Accelerator PhysicsGAMMA P --> GAMMA PNuclear ExperimentDSIG/DOMEGA
researchProduct

"Table 5" of "In-medium modifications of the pi pi interaction in photon-induced reactions."

2005

Differential cross section for PI0PI+/- production with a Carbon target. Errors are statistical only.

GAMMA C --> PI0 PI-Single Differential Cross SectionGAMMA C --> PI0 PI+PhotoproductionDSIG/DMExclusiveGAMMA NUCLEUS --> PI- PI0GAMMA NUCLEUS --> PI+ PI0
researchProduct

"Table 5" of "Quasi-free Compton Scattering and the Polarizabilities of the Neutron"

2003

Energy dependence of the free neutron differential cross section.

Single Differential Cross SectionPhotoproductionElasticAstrophysics::High Energy Astrophysical PhenomenaGAMMA N --> GAMMA NNuclear Theory1.125-1.255Nuclear ExperimentDSIG/DOMEGA
researchProduct

"Table 4" of "Quasi-free Compton Scattering and the Polarizabilities of the Neutron"

2003

Energy dependence of the triple differential cross section w.r.t. the scattered neutron.

PhotoproductionAstrophysics::High Energy Astrophysical PhenomenaNuclear TheoryTriple Differential Cross SectionExclusiveGAMMA DEUT --> GAMMA P NNuclear ExperimentD3SIG/DE/DOMEGA/DOMEGA
researchProduct

"Table 1" of "Quasi-free Compton Scattering and the Polarizabilities of the Neutron"

2003

Energy dependence of the free-proton differential cross section.

Single Differential Cross SectionPhotoproductionElasticNuclear TheoryPhysics::Accelerator PhysicsGAMMA P --> GAMMA P1.13-1.327Nuclear ExperimentDSIG/DOMEGA
researchProduct