Escape of charged particles at stopping annihilation of antiprotons in theheavy nuclei of nuclear photoemulsion

"Rare" annihilation channels for antiprotons stopping on heavy (Ag, Br) nuc lei of photoemulsion, have been sought; 4872 stops of antiprotons on photoe mulsion nuclei are analysed. Events of formation and decay of the hyperfrag ment H-4(Lambda), escape of He-8 and Li-8 nuclei, one-prong stars with the mean range 79.5 +/- 5.1 mum of secondary slow "b" particles are found among the annihilation stars at (p) over tilde capture on nuclei (Ag, Br). The l ower limits for the production probability H-4(Lambda) and He-8, Li-8 nucle i per antiproton stopping in the nuclei (Ag, Br) are W-Lambda(H)4 greater than or equal to 2 x 10(-4) and W-8He,W-8Li = (1.3 +/- 0.6) x 10(-3).(.) The branching ratio for the production of one-prong stars with the secondar y "b" particles is at least (1.3 +/- 0.6) x 10(-3). Possible mechanisms for a production of these events in annihilation processes are considered. (C) 2001 Published by Elsevier Science Ltd.