Production and electromagnetic decay of hyperons: a feasibility study with HADES as a phase-0 experiment at FAIR

Abstract A feasibility study has been performed in order to investigate the performance of the HADES detector to measure the electromagnetic decays of the hyperon resonances $$\Sigma (1385)^{0}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Σ</mml:mi><mml:msup><mml:mrow><mml:mo>(</mml:mo><mml:mn>1385</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:mn>0</mml:mn></mml:msup></mml:mrow></mml:math> , $$\Lambda (1405)$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Λ</mml:mi><mml:mo>(</mml:mo><mml:mn>1405</mml:mn><mml:mo>)</mml:mo></mml:mrow></mml:math> and $$\Lambda (1520)$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Λ</mml:mi><mml:mo>(</mml:mo><mml:mn>1520</mml:mn><mml:mo>)</mml:mo></mml:mrow></mml:math> as well as the production of double strange baryon systems $$\Xi ^{-}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mi>Ξ</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math> and $$\Lambda $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>Λ</mml:mi></mml:math> $$\Lambda $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>Λ</mml:mi></mml:math> in p + p reactions at a beam kinetic energy of $$4.5\,{\mathrm{GeV}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>4.5</mml:mn><mml:mspace/><mml:mi>GeV</mml:mi></mml:mrow></mml:math> . The existing HADES detector will be upgraded by a new Forward Detector, which extends the detector acceptance into a range of polar angles that plays a crucial role for these investigations. The analysis of each channel is preceded by a consideration of the production cross-sections. Afterwards the expected signal count rates using a target consisting of either liquid hydrogen or polyethylene are summarized.