Mid-rapidity spectra and yields of K- and K+ have been measured for Au + Au collisions at 4, 6, 8, and 10.7 AGeV. The K- yield increases faster with beam energy than for K+ and hence the K-/K+ ratio increases with beam energy. This ratio is studied as a function of both √s and √s - √s(th) which allows the direct comparison of the kaon yields with respect to the production threshold in p + p reactions. For equal √s - √s(th) the measured ratio K-/K+ = 0.2 at energies above threshold in contrast to the K-/K+ ratio of near unity observed at energies below threshold. The use of the K-/K+ ratio to test the predicted changes of kaon properties in dense nuclear matter is discussed. (C) 2000 Elsevier Science B.V.
|Number of pages||8|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2000 Sep 28|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics