0000000001000244

AUTHOR

E. Czerwinski

showing 4 related works from this author

Search for the $��$ mesic $^3$He in the $pd\rightarrow d p ��^{0}$ reaction with the WASA-at-COSY facility

2020

The excitation function for the $pd\rightarrow$ $d p ��^{0}$ reaction has been measured by WASA-at-COSY experiment with the aim of searching for $^{3}\hspace{-0.03cm}\mbox{He}$-$��$ mesic nuclei. The measurement in the vicinity of $��$ meson production was performed using a ramped proton beam. The data analysis and interpretation was carried out with the assumption that the $��$-mesic Helium decays via the formation of an intermediate N$^{*}$(1535) resonance. No direct signal of the $��$-mesic nucleus is observed in the excitation function. We determine a new improved upper limit for the total cross section for the bound state production and decay in the $pd\rightarrow$ $(^{3}\hspace{-0.03c…

Nuclear TheoryHigh Energy Physics::PhenomenologyFOS: Physical sciencesNuclear Experiment (nucl-ex)Nuclear Experiment
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Search for the $\eta$ mesic $^3$He in the $pd\rightarrow d p \pi^{0}$ reaction with the WASA-at-COSY facility

2020

The excitation function for the $pd\rightarrow$ $d p \pi^{0}$ reaction has been measured by WASA-at-COSY experiment with the aim of searching for $^{3}\hspace{-0.03cm}\mbox{He}$-$\eta$ mesic nuclei. The measurement in the vicinity of $\eta$ meson production was performed using a ramped proton beam. The data analysis and interpretation was carried out with the assumption that the $\eta$-mesic Helium decays via the formation of an intermediate N$^{*}$(1535) resonance. No direct signal of the $\eta$-mesic nucleus is observed in the excitation function. We determine a new improved upper limit for the total cross section for the bound state production and decay in the $pd\rightarrow$ $(^{3}\hspa…

High Energy Physics::ExperimentNuclear ExperimentNuclear Experiment
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Determination of the eta'-proton scattering length in free space

2014

Taking advantage of both the high mass resolution of the COSY-11 detector and the high energy resolution of the low-emittance proton-beam of the Cooler Synchrotron COSY we determine the excitation function for the pp --> pp eta' reaction close-to-threshold. Combining these data with previous results we extract the scattering length for the eta'-proton potential in free space to be Re(a_{p eta'}) = 0+-0.43 fm and Im(a_{p eta'}) = 0.37(+0.40)(-0.16) fm.

Physics::Accelerator PhysicsFOS: Physical sciencesHigh Energy Physics::ExperimentNuclear Experiment (nucl-ex)Nuclear ExperimentNuclear ExperimentAstrophysics::Galaxy Astrophysics
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Limit on the production of a light vector gauge boson in $\phi $ mesondecays with the KLOE detector

2012

We present a new limit on the production of a light dark-force mediator with the KLOE detector at DAPHNE. This boson, called U, has been searched for in the decay phi --> eta U, U --> e+ e-, analyzing the decay eta --> pi0 pi0 pi0 in a data sample of 1.7 fb-1. No structures are observed in the e+e- invariant mass distribution over the background. This search is combined with a previous result obtained from the decay eta --> pi+ pi- pi0, increasing the sensitivity. We set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of alpha'/alpha < 1.7x10^-5 for 30<M_U<400 MeV and alpha'/alpha < 8x10^-6 for the sub-region 50<M_U<210 MeV. This…

Dark forcesNuclear and High Energy PhysicsParticle physicsElectron–positron annihilationFOS: Physical sciences01 natural sciencesSettore FIS/04 - Fisica Nucleare e Subnuclearee(+)e(-) Collisions Dark forces Gauge vector bosonHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)e(+)e(-) Collisions0103 physical sciencesgauge vector bosonInvariant massNuclear Experiment010306 general physicsBosonPhysicsCoupling constantGauge boson$e^{+}e^{-}$ collisions010308 nuclear & particles physicsSettore FIS/01 - Fisica SperimentaleForm factor (quantum field theory)Vector meson dominancePhi mesondark forcesHigh Energy Physics::ExperimentGauge vector boson
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