Search for the K−pp bound state via γd→K+

Kaonic nuclear state search at J-PARC

“…∼ 100 MeV, having Γ ∼ 120 MeV/c 2 [5]. Conversely, no significant structure was observed in a SPring-8/LEPS induced inclusive experiment [6] or in a proton-proton interaction by the HADES/GSI collaboration [7].…”

“…Experimentally, there are few positive reports on peak structure observations as for the candidate at ∼100 MeV below KNN threshold. The first report from FINUDA group showing a peak structure in the back-to-back Λp invariant mass spectra via the stopped kaon reaction on 6 Li, 7 Li, and 12 C targets [4], having binding energy (B.E.) ∼ 115 MeV, and a width (Γ) ∼ 70 MeV.…”

The Peak Structure in the In-Flight3He(K−, Λp)nReaction Around the \(\bar{K}NN\) Threshold

“…One is that kaonic nuclei are exotic states of many-body systems tied by the strong interaction, which contain a hadron other than nucleons, and the other is that kaonic nuclei are a good "laboratory" to prove kaons in finite nuclear density. In particular, the simplest kaonic nucleusKNN(I = 1/2), sometimes called K − pp, has been intensively studied in both theoretical [3][4][5][6][7][8][9] and experimental [10][11][12][13][14] sides (see also Ref. [15]).…”

Search for theK−ppbound state via the in-flight3He(K−,n) reaction

“…There are various theoretical predictions of the K − pp state at present, thus it is quite important to compare the theoretical calculations with experimental studies. However, the experimental situation is also controversial; The FINUDA [13] and the DISTO [14] collaborations have claimed observations of the deeply-bound K − pp state, while LEPS [15] group recently reported null results of the K − pp population. Therefore, we need to investigate the K − pp state in different reactions and to understand background processes, such as multinucleon absorption processes of K − The E15 experiment was proposed to search for the simplest kaonic nuclear bound states, namely K − pp, via the in-flight 3 He(K − , N) reaction using 1.0 GeV/c K − beam [16].…”