FLAVOR SYMMETRY BREAKING IN ANTI-QUARK DISTRIBUTIONS

We show that knowledge of the valence quark distribution of a proton at one value of q2, enables one to calculate a contribution to the difference between the distribution of anti-up quarks (up) and anti-down quarks (dp) in the sea of the proton at higher values of q2. This difference can be expressed as a linear combination of the structure functions F1, for νp → νX and e-p → e-p (for which one knows the q2 behaviour of the moments) and for νp → μ-X and νp → μ+X (for which one knows the q2 behaviour of the odd moments). The calculable contribution involves a non-trivial continuation of the even (odd) moments of the neutral (charged) current structure functions to odd (even) moments. We calculate this contribution and although we find that its sign is negative we point out that this cannot be interpreted as a consequences of the Pauli exclusion principle. We discuss the constraints our results impose on antiquark distributions. © 1979.