Indication of a deeply bound and compact K-pp state formed in the pp→pΛK+ reaction at 2.85 GeV

T. Yamazaki, M. Maggiora, P. Kienle, K. Suzuki, A. Amoroso, M. Alexeev, F. Balestra, Y. Bedfer, R. Bertini, L. C. Bland, A. Brenschede, F. Brochard, M. P. Bussa, Seonho Choi, M. L. Colantoni, R. Dressler, M. Dzemidzic, J. Cl Faivre, L. Ferrero, J. ForyciarzI. Fröhlich, V. Frolov, R. Garfagnini, A. Grasso, S. Heinz, W. W. Jacobs, W. Kühn, A. Maggiora, D. Panzieri, H. W. Pfaff, G. Pontecorvo, A. Popov, J. Ritman, P. Salabura, S. Sosio, V. Tchalyshev, S. E. Vigdor

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We have analyzed data of the DISTO experiment on the exclusive pp→pΛK+ reaction at 2.85 GeV to search for a strongly bound compact K-pp(X) state to be formed in the pp→K ++X reaction. The observed spectra of the K+ missing mass and the pΛ invariant-mass with high transverse momenta of p and K + revealed a broad distinct peak of 26-σ confidence with a mass MX=2267±3(stat)±5(syst)MeV/c2 and a width ΓX= 118±8(stat)±10(syst)MeV. The enormously large cross section indicates formation of a compact K-pp with a large binding energy of BK=103MeV, which can be a possible gateway toward cold and dense kaonic nuclear matter.

Original languageEnglish (US)
Article number132502
JournalPhysical Review Letters
Issue number13
StatePublished - Apr 1 2010
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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    Yamazaki, T., Maggiora, M., Kienle, P., Suzuki, K., Amoroso, A., Alexeev, M., Balestra, F., Bedfer, Y., Bertini, R., Bland, L. C., Brenschede, A., Brochard, F., Bussa, M. P., Choi, S., Colantoni, M. L., Dressler, R., Dzemidzic, M., Faivre, J. C., Ferrero, L., ... Vigdor, S. E. (2010). Indication of a deeply bound and compact K-pp state formed in the pp→pΛK+ reaction at 2.85 GeV. Physical Review Letters, 104(13), [132502].