The mass spectrum for orbitally excited dibaryon resonances is predicted under the assumption of two clusters of quarks in a stretched bag. Decay mechanisms, stability, and experimental candidates in the Y = 2, 1, and 0 channels are discussed. Natural explanations are found for, e.g., the 3F3 and 'D, pp resonances, for the shoulder at 2.14 GeV, and the enhancement at 2.25 GeV in the Ap invariant-mass spectrum.

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In the MIT bag model we calculate the masses of all colorless N-quark states, for A' = 3, 6, 9, 12, 15, and 18, with the quarks in s ,,, states of the bag. For fixed N these states belong to only one SU (6) irreducible representation. We give SU(6) mass formulas for these states. Several candidates for the lightest N = 6 states are already available. Especially in the A N channel the lowest three predicted states seem to show up in the data.

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Angular momentum excitations of six quarks in a bag give a rich resonance structure in the NN channel above P^ab -1.3 GeV/c. Some states occur with quantum numbers foreign to NN^ which we refer to as extraneous states. The lowest negative-parity states are an (NNj^P^ resonance and two extraneous 7 = 0 states with J^ = 0" and 2", all around 2.2 GeV. The latter two states mainly decay in NN'K. The lowest (NN)^F3 resonance lies at M=2.34GeV.Increasing experimental evidence^ for some resonances in the NN system is being reported. The results on pp scattering with polarized targets and beams above P-^^ 1 GeY/c show a surprisingly rich structure. Analyses^^ of these/)/) data indicate the existence of a resonance in one of the imcoupled spin-triplet partial waves {^P^, ^Fg,...) at M ^ 2.3 GeV and possibly also a resonance in one of the spin-singlet states {^SQ,^D2, ...) aroundM ^2A GeV. Angular distributions and polarizations indicate that the ^F^ assignment for this uncoupled spin-triplet state is favored. Deuteron photodisintegration experiments^ give evidence for a resonance around 2.38 GeV.Conventionally^ one tries to explain these resonances as strong interactions with a channel coupled to the NN channel. A (not too deeply) bound state in the coupled channel will show up as a resonance in NN, in the neighborhood of the threshold for that channel. We note that the NN system cannot have the quantum numbers 1 = 0, J^ = 0'^,0", 2",4",... and/=l, J^= 1+, S"', 5*, We call states with those quantum numbers extraneous to the NN channel and will denote them by Xjjp. Recently Jaffe^ proposed a quite novel type of resonance. He indicated the possible existence of boxmd states of six quarks in a bag. One assumes here the quarks to be in s states of a spherical bag. These resonances necessarily have positive parity. One finds 1=1 resonances in the ^SQ (M = 2.17 GeV) and ^D^ (M = 2.36 GeV) waves and 7=0 resonances in the ^S^ (M =2.24 GeV) and ^D^ (M = 2.36 GeV) waves.The masses of these states which contain iNr= 6 nonstrange quarks can be calculated in the spherical-bag approximation in which the mass operator is given bywhere B= 59.2 MeV fm"^ Zo= 363 MeV fm, and a^= 2.20 are the parameters determined from the g^ and qq spectrum."^ The nonstrange-quark energy is measured by a" = 403 MeV fm and the color magnetic-interaction strength by MQO= 34.9 MeV fm. The color magnetic mass splitting is determined byF^ is the color SU(3) quadratic Casimir operator. In the bag model the mass of a colorless state is found by minimizing the eigenvalue of the mass