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We describe a measurement of the direct CP asymmetry between inclusive b-->s gamma and b-->s gamma decays. This asymmetry is expected to be less than 0.01 in the standard model, but could be enhanced up to about 0.10 by new physics contributions. We use a sample of 89 x 10(6) BB pairs recorded with the BABAR detector at SLAC PEP-II, from which we reconstruct a set of 12 exclusive b-->s gamma final states containing one charged or neutral kaon and one to three pions. We measure an asymmetry of A(CP)(b-->s gamma)=0.025+/-0.050(stat)+/-0.015(syst), corresponding to an allowed range of -0.06s gamma)<+0.11 at 90% confidence level.

649their errors. Essentially the same weights were obtained independently from a consideration of the line widths and rates of drift in the various runs. If we take into account the small uncertainties of'gj(K) and gj(Cs) we obtain g /(Cr) = 2 (1.00081±0.00005). DISCUSSION AND CONCLUSIONOur measurements show that the ground state of Cr is a much "better" S state than was indicated by the less accurate optical value for gj. However, gj-(Cr) does differ by approximately 3 parts in 10 4 from g 8 , the pure electron spin g factor. This discrepancy can be due to several factors: (a) interaction terms in the radiative correction, 10,11 (b) nonradiative relativistic correction, 12 (c) diamagnetic correction, 13 and (d) perturbations due to higher states. The effects (a) and (b) have been calculated for some spectra with one or two 11 valence electrons and have been found to be much smaller than 3X10 -4 . No calculations are available for Cr which has six valence electrons. The diamagnetic correction (c) is negligible 13 (-2X10" 6 for Cr). The deviation of gj(Cr) from g s that has been found is indeed in the direction to be expected from a perturbation (d), but no quantitative conclusions can be drawn until the corrections (a) and (b) are known. 10 G. Breit, Phys. Rev. 39, 616 (1932). have pointed out the importance of the Be 8 (a,7)C 12 reaction in hot stars which have largely exhausted their central hydrogen. Hoyle 3 explains the original formation of elements heavier than helium by this process and concludes from the observed cosmic abundance ratios of 0 16 :C 12 :He 4 * On leave from the