Final-state interactions in the process $$\bar pp \to pK^ + \Lambda$$

Abstract

Abstract. The possibility to determine the pΛ scattering length from the final-state interaction in the reaction pp → pK + Λ is investigated experimentally. From a transversely polarized measurement, the K + analyzing power (AN ) which, in principle, allows one to extract the spin triplet scattering length is studied. An unexpected energy dependence of the forward/backward symmetric part of AN is found. The influence of N * resonances on the pΛ invariant mass spectrum is investigated by exploiting the large acceptance for the process pp → pK− and is found to be the main source of uncertainty for determining the pΛ scattering length.PACS. 13.75.-n Hadron-induced low-and intermediate-energy reactions and scattering (energy ≤ 10 GeV) -13.75.Ev Hyperon-nucleon interactions -25.40.Ve Other reactions above meson production thresholds (energies > 400 MeV)

Status of X(1835) and pp¯ Interaction from Chiral Symmetry

“…Inversely, a bound state clearly indicates the importance of the two-body strong interaction. There is an interesting example: the enhancement of Λp mass spectra in pp → pΛK + [16] can not be attributed to the near threshold Λp bound state, see also the discussion in Ref. [14].…”

Reanalysis ofp+preaction data: Probable absence of appK−state

“…Three issues were mainly investigated thereby: the production of N * resonances and their subsequent decay into K + Λ [2][3][4][5][6][7][8][9][10], the pΛ final state interaction [7,[11][12][13], and the cusp structure appearing at 2.13 GeV in the pΛ invariant mass distribution [14][15][16]. A fourth aspect was recently added to this list with the investigation of the kaonic nuclear bound state KN N by the DISTO collaboration [17,18].…”

$\Sigma^{0}$ identification in proton induced reactions on a nuclear target

“…Due to strangeness conservation, hyperon production has to be accompanied by the production of at least one kaon and hence leads to an energy threshold in NN of 2.518 GeV for Λ and 2.623 GeV for Σ 0 . Plenty of data are available for Λ hyperons within a broad range of collision energies [1,2,3,4,5], while the situation is much more difficult for the Σ 0 hyperon, where no data exists between 80 MeV and 2 GeV in excess energy above free nucleon nucleon production threshold [6,7,8].…”