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A statistical combination of the experimental lifetime estimations available in the literatures is performed for 3 Λ H and 4 Λ H, including several recent measurements. The combined average values of the lifetime for 3 Λ H and 4 Λ H are respectively 216−16+19 ps and 192−18+20 ps with a reduced χ2 of 0.89 and 0.48. A new insight into the lifetime estimation of the HypHI Phase 0 experiment by a Bayesian approach is also presented. In this approach, several different prior distributions including the combination of previous lifetime data and a Jeffrey prior are used. The principal mode and the smallest credible interval at 68% of the posterior distribution, given by the prior belief of the previous measurements, are 217−16+19 ps and 194−18+20 ps respectively for 3 Λ H and 4 Λ H. The two employed approaches have revealed that the lifetime of hypernuclei 3 Λ H and 4 Λ H can be shorter than the Λ –hyperon lifetime.

WOS: 000358624800021, Hypernuclear production cross sections have been deduced for the first time with induced reaction of heavy ion beam on fixed target and by means of the invariant mass method by the HypHI Collaboration exploiting the reaction of Li-6 C-12 at 2 A GeV or root S-NN = 2.70 GeV. A production cross section of 3.9 +/- 1.4 mu b for H-3(Lambda) and of 3.1 +/- 1.0 mu b for H-4(Lambda) respectively in the projectile rapidity region was inferred as well as the total production cross section of the Lambda hyperon was measured and found to be equal to 1.7 +/- 0.8 mb. A global fit based on a Bayesian approach was performed in order to include and propagate statistical and systematic uncertainties. Production ratios of H-3(Lambda)/H-4(Lambda), H-3(Lambda)/Lambda and H-4(Lambda)/Lambda were included in the inference procedure. The strangeness population fattors S-3 and S-4 of H-3(Lambda) and H-4(Lambda) respectively were extracted. In addition, the multiplicities of the Lambda hyperon, H-3(Lambda), and H-4(Lambda) together with the rapidity and transversal momentum density distributions of the observed hypemuclei were extracted and reported. (C) 2015 The Authors. Published by Elsevier B.V., Helmholtz Association as Helmholtz-University Young Investigators Group at GSI [VH-NG-239]; German Research Foundation (DFG) [SA 1696/1-1]; Ministry of Education, Science and Culture of Japan [449, 18042008]; EU; GSI Department of Accelerator; GSI Department of Experimental Electronics; GSI Department of the Detector Laboratory; GSI Department of the Target Laboratory; Electronics Department of the Institute for Nuclear Physics of Mainz University, The authors would like to thank the GSI Departments of Accelerator, of Experimental Electronics, of the Detector Laboratory and of the Target Laboratory and the Electronics Department of the Institute for Nuclear Physics of Mainz University for supporting the project. The HypHI project is funded by the Helmholtz Association as Helmholtz-University Young Investigators Group VH-NG-239 at GSI, and the German Research Foundation (DFG) under contract number SA 1696/1-1. The authors acknowledge the financial support provided by the Ministry of Education, Science and Culture of Japan, Grant-in-Aid for Scientific Research on Priority Areas 449, and Grant-in-Aid for promotion of Cooperative Research in Osaka Electro-Communication University (2004-2006). This work is also supported by the Ministry of Education, Science and Culture of Japan, Grants-in-Aid for Scientific Research 18042008 and EU FP7 Hadron-Physics-2 SPHERE. A part of this work was carried out on the HIMSTER high performance computing infrastructure provided by the Helmholtz-Institute Mainz. We would also like to thank to A. Botvina, T. Gaitanos, and H. Lenske for the involved discussions.