2012ApJ...750...52N

The amount and distribution of heavy elements in Jupiter gives indications on the process of its formation and evolution. Core mass and metallicity predictions, however, depend on the equations of state (EOSs) used and on model assumptions. We present an improved ab initio hydrogen EOS, H-REOS.2, and compute the internal structure and thermal evolution of Jupiter within the standard three-layer approach. The advance over our previous Jupiter models with H-REOS.1 by Nettelmann et al. is that the new models are also consistent with the observed ≳ 2 times solar heavy element abundances in Jupiter's atmosphere. Such models have a rock core mass M_c= 0-8 M _⊕, total mass of heavy elements M_Z= 28-32 M_⊕, a deep internal layer boundary at ≥ 4 Mbar, and a cooling time of 4.4-5.0 Gyr when assuming homogeneous evolution. We also calculate two-layer models in the manner of Militzer et al. and find a comparable large core of 16-21 M _⊕, out of which ∼11 M_⊕ is helium, but a significantly higher envelope metallicity of 4.5 times solar. According to our preferred three-layer models, neither the characteristic frequency (ν₀∼ 156 µHz) nor the normalized moment of inertia (λ ∼0.276) is sensitive to the core mass but accurate measurements could well help to rule out some classes of models.