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The four lightest quarks - up(u), down (d), strange (s) and charm (c) - can be arranged in 20 different ways to create baryons. All the baryons containing zero or one charm quark have been detected in experiments. Now, for the first time, the SELEX experiment has observed baryons containing two charm quarks. Baryons can have "spins" of 1/2 (top) or 3/2 (bottom) depending on how the three quarks - which all have spins of 1/2 - line up together. Only 16 of the 20 combinations can exist in the lowest spin state, while all 20 can exist in the highest. The charge on the baryon is found by adding the charges on the quarks: +2/3 for up and charm quarks, and -1/3 for down and strange quarks. The proton, for instance, contains two up and one down quark and has a spin of 1/2; the same three quarks can also combine to form an excited state with a spin of 3/2 that is known as a Δ+ baryon. Picture credit: Fermilab.