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arXiv · 1903.12032

Delta mass shift as a thermometer of kinetic decoupling in Au+Au reactions at 1.23 AGeV

Tom Reichert·Paula Hillmann·Ayut Limphirat·Christoph Herold·Marcus Bleicher
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Abstract

The HADES experiment at GSI will soon provide data on the production and properties of $Δ$(1232) baryons from Au+Au reactions at 1.23 AGeV. Using the UrQMD model, we predict the yield and spectra of $Δ$(1232) resonances. In addition we show that one expects to observe a mass shift of the $Δ$(1232) resonance on the order of 50 MeV in the reconstructable $Δ$(1232) mass distribution. This mass shift can be understood in terms of late stage $Δ$(1232) formation with limited kinetic energy. We show how the mass shift can be used to constrain the kinetic decoupling temperature of the system.

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Tom Reichert, Paula Hillmann, Ayut Limphirat, Christoph Herold, Marcus Bleicher. 2019-09-13. Delta mass shift as a thermometer of kinetic decoupling in Au+Au reactions at 1.23 AGeV. https://doi.org/10.1088/1361-6471%2Fab34fa

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