First Measurement of the EMC Effect in $^{10}$B and $^{11}$B

Abstract

The nuclear dependence of the inclusive inelastic electron scattering cross section (the EMC effect) has been measured for the first time in 10 B and 11 B. Previous measurements of the EMC effect in A ≤ 12 nuclei showed an unexpected nuclear dependence; 10 B and 11 B were measured to explore the EMC effect in this region in more detail. Results are presented for 9 Be, 10 B, 11 B, and 12 C at an incident beam energy of 10.6 GeV. The EMC effect in the boron isotopes was found to be similar to that for 9 Be and 12 C, yielding almost no nuclear dependence in the EMC effect in the range A = 4 − 12. This represents important, new data supporting the hypothesis that the EMC effect depends primarily on the local nuclear environment due to the cluster structure of these nuclei.