Experimental Review of ?? over bar Production

Exclusive hyperon-antihyperon production provides a unique insight for understanding of the intrinsic dynamics when strangeness is involved. In this paper, we review the results of lambda lambda over bar production via different reactions from various experiments, e.g., via p over bar p annihilation from the LEAR experiment PS185, via electron-positron annihilation using the energy scan method at the CLEO-c and BESIII experiments and the initial-state-radiation approach utilized at the BaBar experiment. The production cross section of lambda lambda over bar near the threshold is sensitive to QCD based prediction. Experimental high precision data for p over bar p & RARR;lambda over bar lambda close to the threshold region is obtained. The cross section of e(+)e(-)& RARR;lambda lambda over bar is measured from its production threshold to high energy. A non-zero cross section for e(+)e(-)& RARR;lambda lambda over bar near threshold is observed at BaBar and BESIII, which is in disagreement with the pQCD prediction. However, more precise data is needed to confirm this observation. Future experiments, utilizing p over bar p reaction such as PANDA experiment or electron-positron annihilation such as the BESIII and BelleII experiments, are needed to extend the experimental data and to understand the lambda lambda over bar production.

Automated summary

This paper reviews the results of lambda lambda over bar production via different reactions from various experiments and highlights the significance of studying the production cross section near the threshold for understanding the intrinsic dynamics involving strangeness. Experimental data from different experiments show some discrepancies with QCD predictions, indicating the need for further investigation.