Search for a short-lived H dibaryon through H-> /\ p pi in 11.6 A GeV/c Au-Au Collisions at AGS.

Abstract

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A new experiment has been conducted at Brookhaven Alternating Gradient Synchrotron (AGS) to perform a sensitive search for the long sought for short-lived H dibaryon by detecting many possible decay channels and study hyperon production in 11.6 GeV/c Au + Au collisions. The experiment E896 features a high data rate distributed drift chamber(DDC) loacated 1 m from the target and inside a 1.8 T dipole magnet. The DDC is designed to make unambiguous identification of a number of possible H decay topology and to provide precise track information. In addition, Time of flight(TOF) walls and a MUlti-Functional Neutron Spectrometer(MUFFINS) are used for particle identification. The charged particles will be identified by TOF and neutrons by MUFFINS.

The H dibaryon, predicted in the context of MIT bag model by Jeffe in 1977, is a spinless, isoscalar six-quark state with quark configuration uuddss, baryon number B=2, spin-parity = 0+, and strangeness S = -2. There have been a number of theoretical calculations for the H mass and its lifetime, most of them favor a weakly bound H with massses between the lambda-neutron threshold of 2.06 GeV and the lambda-lambda 2.23 GeV. In this scheme, there are various possible decay channels for the H dibaryon, and E896 is an experiment to be sensitive to many of these.

The E896 have completed its first Au run and data taking for the last two weeks of January, 1997. In this dissertation, results of the analysis of one of the most probable H decay modes, H -> /\ p pi is presented as well as estimates of H production through heavy ion collisions and Monte Carlo simulation of DDC performance.

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