We study the fluctuation properties of $\Delta T=0$ electromagnetictransition intensities and electromagnetic moments in $A \sim 60$ nuclei withinthe framework of the interacting shell model, using a realistic effectiveinteraction for $pf$-shell nuclei with a $^{56}$Ni core. The distributions of the transitionintensities and of the electromagnetic moments are well described by theGaussian orthogonal ensemble of random matrices. In particular, the transitionintensity distributions follow a Porter-Thomas distribution. When diagonalmatrix elements (i.e., moments) are included in the analysis of transitionintensities, we find that the distributions remain Porter-Thomas except for theisoscalar $M1$. The latter deviation is explained in terms of the structure ofthe isoscalar $M1$ operator.
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