The focus of the G experiment at Jefferson Lab is the contribution of the strange quark to the character of the proton. The effects of different flavors of quarks can be disentangled by comparing the electromagnetic and weak contributions, since the electromagnetic and weak couplings of the various flavors differ. The weak interaction can be isolated for study because it violates parity symmetr...

Appearance: The reversed halo sign (also known as the atoll sign, reverse halo sign, and the fairy ring sign) is defined by central ground-glass opacity with a surrounding halo or crescent of consolidation (Fig. 1). This should not be confused with the halo sign which refers to central consolidation with a surrounding halo or rim of ground-glass opacity. Furthermore, the reversed halo sign shou...