C. Mayeur

A determination of the binding-energy values of light hypernuclei

Abstract The results of an experimental study of the binding energies of light hypernuclei are presented, based on a sample of 2008 uniquely identified π − mesonic decays. The problems of the calibration procedure and the selection criteria are discussed. Various aspects of the Λ -N interaction are reviewed in the light of these new results.

The production of heavy hyperfragments by K--meson captures at rest in emulsion nuclei

SummaryIn this study of hyperfragment production by K--meson absorptions at rest in emulsion nuclei, an attempt has been made to estimate the contribution of heavy spallation hyperfragments to the total observed number. In a sample of 24 640 K--meson captures, 1612 secondary events have been attributed to the production and subsequent decay of hyperfragments. From a study of the characteristics of both the production and decay disintegrations, it is concluded that about one half of the observed hyperfragments consists of λ0-hyperons trapped in the heavy spallation products of silver and bromine and these are almost entirely confined to the (0/3) μm range interval. The consequences of their presence aie discussed.RiassuntoIn questo studio della produzione di iperframmenti nell’assorbimento di mesoni K-in quiete nei nuclei dell’emulsione, si fa un tentativo di valutare il contributo dei frammenti pesanti di demolizione al numero totale osservato. In un campione di 24 640 catture di mesoni K-, 1612 eventi secondari sono stati attribuiti alla produzione e successivo decadimento degli ipeiframmenti. Da uno studio delle caratteristiche delle disintegrazioni sia di produzione che di decadimento, si conclude che circa la metà degli iperframmenti osservati consiste di iperoni Λ0 catturati nei prodotti pesanti di demolizione dell’argento e del bromo ed essi sono quasi interamente conflnati nel-Pintervallo di percorso (0/3) μm. Si discutono le conseguenze della loro presenza.

Branching ratios for the π− mesonic decays of the hypernuclei Λ3H and Λ4H

Results are presented concerning the experimental determination, with large statistics, of the branching ratios for the π− mesonic decay of the hypernuclei Λ3H and Λ4H. The spin assignments J(Λ3H) = 12and J(Λ4H) = 0 are confirmed.

A determination of the\(B_\Lambda \) values of light hypernucleivalues of light hypernuclei

SummaryResults are presented on the

The π+-mesonic decays of hypernuclei

B_\Lambda

A measurement of the Ξ hyperon lifetimes and α parameters

values of hypernuclei in the mass rangeA=3 toA=12 obtained from a sample of 595 uniquely identified π−-mesonic decays. The problems of what constitute adequate selection criteria for the unique identification of an event are discussed. The disagreement between the

The question of the existence of a particle-stable Λ6Li hypernucleus

B_\Lambda