Similar to up quarks , charm quarks have a charge of +2 \/ 3 . Although charm quarks are not extremely common , they can be found in particles created by particle accelerators ( which smash atoms together at extremely high speeds ) , such as J \/ Ï mesons , D mesons , and other charmed particles . Example of hadrons containing charm quarks include the J \/ meson , D mesons , charmed Sigma baryons , and other charmed particles .