A generalized Bethe-Weizsaecker mass formula for strange hadronic matter

Technical Report · Tue Dec 01 04:00:00 EST 1992

OSTI ID:10142547

Dover, C B ^[1]; Gal, A ^[2]

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1. Brookhaven National Lab., Upton, NY (United States)
2. Hebrew Univ., Jerusalem (Israel)

The Bethe-Weizsaecker nuclear mass formula is extended to strange hadronic matter composed of nucleons, lambdas and cascade hyperons. The generalized formula contains several volume and symmetry terms constrained by phenomenologically determined {lambda}-nuclear, {xi}-nuclear and {lambda}{lambda} interaction parameters and by hyperon-hyperon ({lambda}{lambda}, {lambda}{xi}, {xi}{xi}) interaction parameters suggested by One-Boson-Exchange models. We find that hypernuclei are generally unstable to {lambda}{lambda} {yields} {xi}N conversion. For strange hadronic matter, as function of the baryon number A, the line of strong-interaction stability, along which a large strangeness fraction {vert_bar}S{vert_bar}/A {approx} 0.5 - 1.1 and a low charge fraction q/A {approx_lt} 0.2 hold, and no fission occurs, is determined. The binding energy per baryon increases monotonically to its bulk limit, B/A {yields} 38 MeV, {vert_bar}S{vert_bar}/A {yields} 1.1 and q/A {yields} 0 for the parameters adopted here assuming that the hyperon species saturate at densities similar to those of protons and neutrons in nuclei. Even in the extreme limit of vanishingly small hyperon-hyperon interaction strengths, strange hadronic matter with B/A {yields} 15 MeV, {vert_bar}S{vert_bar}/A {yields} 0.7 and q/A {yields} 0 in the bulk limit should exist; the mass formula reproduces semi-quantitatively recent mean-field calculations which implicitly assumed weak hyperon-hyperon interactions.

• Research Organization: Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG06-90ER40561; AC02-76CH00016
• OSTI ID: 10142547
• Report Number(s): DOE/ER/40561--096; ON: DE93011010; IN: INT-92-08-02
• Country of Publication: United States
• Language: English

Related Subjects

663110
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BINDING ENERGY
GENERAL AND AVERAGE PROPERTIES OF NUCLEI AND NUCLEAR ENERGY LEVELS
HYPERNUCLEI
LAMBDA PARTICLES
MASS FORMULAE
OBE MODEL
THEORETICAL DATA
WEIZSAECKER FORMULA
XI PARTICLES