The event was found by Y-S.Iwata (MS1) of Gifu Univ on Jan.18.2001. It was located in the bottom plate of an emulsion module. Track-A and -B is a double-lambda hypernucleus and a doughter single-lambda hypernucleus, respectively. Track-C is a pi- because its end point shows sigma-stop topology, and its range is over 13mm. Track-D is escaping from the emulsion module, however, its end point was detected in the downstream SCIFI-block. Lambda-Lambda interaction energy [DLL] was decided by the following production and decay sequence,

1) Xi- + 12C ==> 6LLHe + 3H + 4He 2) 6LLHe ==> 5LHe + 1H + pi- 3) 5LHe ==> AH + A'H + neutron(s).

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