Reduced Hadronic Uncertainty in the Determination of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>V</mml:mi><mml:mrow><mml:mi>u</mml:mi><mml:mi>d</mml:mi></mml:mrow></mml:msub></mml:math>
Physical review letters