Formation of a Narrow Baryon Resonance with Positive Strangeness in K+ Collisions with Xe Nuclei

The data on the charge-exchange reaction K+ Xe -> K(0)pXe', obtained with the bubble chamber DIANA, are reanalyzed using increased statistics and updated selections. Our previous evidence for formation of a narrow pK(0) resonance with mass near 1538 MeV is confirmed. The statistical significance of the signal reaches some 8 ( 6) standard deviations when estimated as S/root B (S/root B + S). The mass and intrinsic width of the Theta(+) baryon are measured as m = 1538 +/- 2 MeV and Gamma = 0.39 +/- 0.10 MeV.