7-spectra and excitation functions of the ~~176 nT) l~176 reaction were measured in the 1.2-3.6MeV proton energy range by using thick, enriched targets, Ge(Li) and low energy photon (hyperpure Ge) spectrometers. These detectors were used in YTcoincidence experiments, too. Conversion electron spectrum measurements were performed by means of a superconducting magnet transporter Si(Li) spectrometer (SMS) at Ep =4MeV and multipolarities of some transitions have been determined. Based on the experimental results a level scheme of l~176 has been constructed. Level energies of l~176 were calculated on the basis of the parabolic rule, derived from the cluster-vibration model.Nuclear Reaction: l~176 nT), E= 1.2-4.0 MeV. Measured Ey, Is(E ), 77-coin, Ece, Ice, l~176 deduced levels, multipolarity of transitions, J, ~c. Enriched target. Van de Graaff accelerator, Ge(Li), hyperpure Ge low energy photon spectrometer (LEPS), superconducting magnet transporter Si(Li) spectrometer (SMS).

Abstract.We discuss the production of strange quark clusters in high energy heavy ion reactions in which a Quark-Gluon-Plasma (QGP) intermediate state is excited. A microscopic fission-chain model (PHASER) has been constructed for the description of QGP rehadronization. Color fluctuations, Q(2 pair production and energy fragmentation have been taken into account. We determined the spin-flavor degeneracy factors and the formation factors for multibaryon quark clusters. Baryon, antibaryon and meson yields have been estimated, as well as those of light multi-strange quark clusters. 12.38.Mk; 25.75. +r PACS: 1.IntroductionThe production and identification of the Quark-GluonPlasma (QGP) state represents a central problem in contemporary nuclear physics. At high enough energy and baryon number, relativistic heavy ion collisions can provide sufficiently high temperature and density for quark and gluon liberation, i.e. the deconfinement phase transition. Heavy ion reactions which pass through the QGP intermediate state are expected to be a powerful tool to produce exotic hadrons and hadronic clusters. Experiments are in progress at the Brookhaven AGS at 14.5 GeV/A and at the CERN SPS at 200 GeV/A beam energies to synthesize and detect the QGP phase. Future experiments at higher energies are planned at the RHIC facility at Brookhaven and the LHC at CERN. The formation of stable multistrange quark clusters ("strangelets"), if such objects indeed exist, could offer a signature of QGP formation. This manuscript has been authored under contract number DE-AC02-76CH00016 with the U.S. Department of Energy. Accordingly, the U.S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes We have formulated a plasma fragmentation mechanism for QGP hadronization. This mechanism provides a new way (besides strangeness separation in the quarkhadron coexistence phase during hadronization) to produce exotic strange clusters. There are theoretical suggestions that strange quark clusters could be stable against strong decay. In addition, antinuclei and anti-strange clusters might be produced in measurable amounts in relativistic heavy ion collisions, if QGP formation occurs.In Sect. 2, we describe in detail our fission-chain model (PHASER) for the description of the hadronization phase transition. In Sect. 3, we discuss the parameters of the initial QGP state. In Sect. 4, baryon and antibaryon yields in the final hadron gas are calculated and the entropy conservation law is discussed. The p/~t, K/~ and some antibaryon/baryon ratios are also presented. Section 5 is devoted to a discussion of the results for light strange cluster yields and ratios. We discuss our predictions in a qualitative way and point out some limitations of our approach. The fission-chain model of QGP fragmentationAfter the QGP state is produced, a crucial question is the mechanism for the rehadronization of QGP. A careful treatment of rehadronizat...

yspectra and integral 7 excitation functions of the 98Mo(p, n ~) ~' T c reaction were measured with Ge(Li) and hyperpure Ge detectors in the 2.4-4.0 MeV energy interval of the bombarding protons. The conversion electron spectrum of the reaction was measured with a superconducting magnet transporter Si(Li) spectrometer. The level scheme of 9 8 T ~, -,branching ratios, multipolarity of transitions, level spin and parity values have been deduced. The energies of '*Tc levels were calculated on the basis of the parabolic rule which was derived from the cluster-vibration model. The experimental level scheme of 9 8 T ~ has been compared with the available theoretical results.

The conversion electron and 7-ray spectra of the 96Zr(p, nT)96Nb reaction were measured with Ge(Li) and superconducting magnet transporter Si(Li) spectrometers respectively, at 4 MeV bombarding proton energy. The multipolarities of some transitions were determined and conclusions were drawn on the spins and parities of the excited states of 96Nb. ENuclear Reactions: 96Zr(p, n7), E=4MeV; measured E~, 17, Ece , Ice , cc.Deduced multipolarity of transitions, J, zc of 96Nb levels. Ge(Li) and superconducting magnet transporter Si(Li) spectrometers. Enriched target.

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