A quark and an anti - quark combine to form a meson. The pi-meson family is made up of u and d quarks only. A pi-meson can be positively, negatively or neutrally charged. Give the quark composition of each of the 3 types of pi-meson. The positively charged pion has a composition of an anti down quark and an up quark. The neutrally charged pion has a composition of an anti-up quark and an up quark + an anti down quark and a down quark / square root of 2. What does this mean?? What is the composition of the negatively charged pi meson? Is it these 3 types of mesons it is asking me for the compositions of?