Luminosity determination for the proton-deuteron reaction using pd -> 3He eta channel with WASA-at-COSY detector

In this report one of the methods used for the luminosity determination for the experiment performed by WASA Collaboration to search for 3He-eta mesic nuclei is presented. The method is based on the analysis of pd -> 3He eta process

Production and interaction of the eta meson with nucleons and nuclei

We report on the status of the search for eta-mesic nuclei and the studies of the interaction of the eta meson with nucleons. Recently we have completed the analysis of the new WASA-at-COSY data on the production of the eta meson with polarized proton beam. New results on the analyzing power for the pp->ppeta reaction with more than an order of magnitude improved precision shed a new light on the production mechanism of the eta meson in nucleon-nucleon collisions. Also, the latest results of the search for eta-mesic nuclei are discussed.Comment: 4 pages, presented at 14th International Workshop on Meson Production, Properties and Interaction KRAK\'OW, POLAND (MESON 2016), accepted for publication in EP

Luminosity determination for the proton-deutron reactions using quasi-free reactions with WASA-at-COSY facility

The scientific aim of our research is experimental confirmation of the existence of mesic-nucleus: a new exotic kind of nuclear matter consisting of nucleons and mesons. In this report we present the method of luminosity determination for experiment performed atWASA-at-COSY detector dedicated to search for 3He-η bound state. This method is based on analysis of quasi-free $pd \to ppn_{{\rm{spec}}}$ reaction

Search for η\eta-mesic 3He^{3}He in non-mesonic final state

The experiment on searching for η-mesic 3He nucleus was performed in May 2014 at COSY accelerator in Juelich by WASA-at-COSY Collaboration. The measurements were carried out using ramped beam technique which allows for the slow and continuous beam momentum change near the threshold of η meson creation. The luminosity was obtained based on pd → 3Heη reaction and quasielastic proton-proton scattering. The bound state of η-meson and 3He nucleus is searched for in pd → 3He2γ and pd → 3He6γ channels. The analysis is still in progress and the estimated upper limit value is on the level of few nanobarns

Search for η-mesic 3He in non-mesonic final state

The experiment on searching for η-mesic 3He nucleus was performed in May 2014 at COSY accelerator in Juelich by WASA-at-COSY Collaboration. The measurements were carried out using ramped beam technique which allows for the slow and continuous beam momentum change near the threshold of η meson creation. The luminosity was obtained based on pd → 3Heη reaction and quasielastic proton-proton scattering. The bound state of η-meson and 3He nucleus is searched for in pd → 3He2γ and pd → 3He6γ channels. The analysis is still in progress and the estimated upper limit value is on the level of few nanobarns

Luminosity determination for the proton-deutron reactions using quasi-free reactions with WASA-at-COSY facility

The scientific aim of our research is experimental confirmation of the existence of mesic-nucleus: a new exotic kind of nuclear matter consisting of nucleons and mesons. In this report we present the method of luminosity determination for experiment performed atWASA-at-COSY detector dedicated to search for 3He-η bound state. This method is based on analysis of quasi-free pd→ppnspec$pd \to ppn_{{\rm{spec}}}$ reaction

Searching for

The search for the 4He-η and 3He-η bound states was performed with the WASA-at-COSY facility using a ramped beam technique in 2008, 2010 and 2014, respectively. The 2008 and 2010 data analyses has already been completed and resulted in the upper limits for the total cross sections for the η-mesic 4He production in dd → 3Henπ0 and dd → 3Hepπ− processes. No narrow structure which could be interpreted as a bound state was observed. The experiment carried out in 2014 collected the largest data sample for 3He-η in the world. The data analysis is in progress. This article presents results of the 2010 data analysis and preliminary results of the 2014 data analysis