A Random Walk with Heavy Flavours

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q-30 16 -75 16q-58 0 -92 -27q-49 -39 -78.5 -112t-29.5 -136q0 -34 8.5 -52.5t21.5 -18.5q40 0 109.5 63.5t103.5 115.5q16 53 32 151z" id="x1D45E"></path></g><g transform="matrix(.017,-0,0,-.017,29.011,11.4)"><path d="M901 255q-71 -62 -185 -187l-22 15l102 147h-727v50h727l-102 147l22 15q114 -125 185 -187z" id="x2192"></path></g><g transform="matrix(.017,-0,0,-.017,52.776,11.4)"><path d="M745 361q0 -134 -83.5 -233t-214.5 -130l16 -11q97 -67 250 -132l-8 -23q-76 3 -131 16q-81 19 -242 125l-20 13q-129 8 -209 91t-80 208q0 160 116 271t289 111q136 0 226.5 -83t90.5 -223zM645 356q0 127 -57.5 201.5t-169.5 74.5q-126 0 -210.5 -104.5t-84.5 -248.5
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</svg> Feynman diagram. Bold lines are for heavy quarks (<svg height="14.3125" id="M535" style="vertical-align:-2.2932pt" version="1.1" viewbox="0 0 13.175 14.3125" width="13.175" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>).</table>

Advances in High Energy Physics

A Random Walk with Heavy Flavours

Figure 21