A study of K$^{0}_{s}K^{0}_{s}$ Bose-Einstein correlations in hadronic $Z^{0}$ decays

Bose-Einstein correlations in K0SK0S pairs have been studied for the first time in e+e− annihilations. These correlations were measured through the quantity Q, the four momentum difference of the pair. Out of about half a million Z0 hadronic decay events a total of about 6000 events with two or more identified K0S mesons were used for the analysis We observe a threshold enhancement in K0SK0S pairs originating from a mixed sample of K0 K 0 and K0K0 ( K 0 K 0 ) pairs. Although we can not presently exclude that a part of this effect is due to scalar meson decays, our analysis attributes the enhancement to Bose-Einstein correlations. We find the values for the strength of the effect and the radius of the K0S emitting source to be λ = 1.12 ± 0.33 ± 0.29 and R0 = (0.72 ± 0.17 ± 0.19) fm, respectively, where the first error is statistical and the second systematic.