MASS RATIOS OF THE LIGHT QUARKS

We derive a consistent set of light quark mass ratios which are compatible with the available constraints of chiral symmetry treated to next-to-leading order. Also required as input is resonance saturation of a set of low-energy amplitudes, in particular for the pion and kaon electromagnetic mass difference. The results (md+mu)/ms=1/15.5, (md-mu)/ms=1/29 are modestly different from previous values, and resolve the long-standing puzzle of the η→3π decay rate