Stable Sexaquark

Abstract

It is proposed that the neutral, B=2, flavor singlet sexaquark (S) composed of uuddss quarks, has mass m_S <~ 2 GeV. If m_S < 2 (m_p + m_e), it is absolutely stable, while for m_S < m_p+m_e + m_Lambda, its lifetime can be greater than the age of the Universe. Lattice gauge theory cannot yet predict m_S, but indirect evidence supports the hypothesis of stability. A stable S is consistent with QCD theory and would have eluded detection in accelerator and non-accelerator experiments. If it exists, the S is a good Dark Matter candidate. Analyses of existing Upsilon decay and LHC data can be used to discover it and measure its mass.

Comments: v2: added new sections in Supplementary Materials on naming and Belz et al experiment; added some clarifying material and streamlined elsewhere; updated references