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tokens: driven by neutrino heating, where the MRI significantly enhances the convection and angular momentum transport (Sawai Yamada 2014 ). Although neutrino heating plays an important role, neutron-rich matter is ejected especially in polar directions with a smaller influence of -capture on neutrons due to shorter expansion/explosion timescales. We compute additional models to investigate the effect of magnetic fields in explosion dynamics. However, simulating MRI-driven explosion models with different initial magnetic fields requires a huge amount of computer resources because the saturation of the MRI is strongly depending on the magnetic fields, i.e., all explosion models have different criteria for numerical convergence (see Figure 6 of Sawai Yamada 2016 ). In the current study, therefore, we adopt a more simplified parametric method based on the above MRI-driven explosion model (shown in Figure 1 ), whose numerical convergence has been confirmed. 8 8 We confirmed that a higher-resolution model, of which the finest grid is 30 m, shows the same result of r-process nucleosynthesis (plotted in Figure 4 ) as well as explosion dynamics. Instead of changing magnetic fields, we vary the time evolution of neutrino luminosity by multiplying a scale factor as , 0.20, 0.30, 0.40, 0.50, 0.60, 0.75, and 1.25. We suppose that explosion models with a lower are dominated by magnetic fields rather than neutrino-heating. To evaluate the strength of magnetic fields in jets, we consider the minimum value of the ratio of gas to magnetic pressure (), i.e., Since the has a large fluctuation, we calculate the mean value denoted by during jet propagation (from jet launching to the time the shock front reaches 2000 km). A lower is obtained in models with lower , where , 0.038, 0.047, 0.060, 0.071, 0.083, 0.15, 0.20, and 0.30 in ascending order of . We expect neutron-rich material to be mostly ejected in magnetically driven jets rather than heating-driven ejecta. In the jet direction, neutrino emission can be weakened due to lower mass accretion onto the proto-NS. Adopting a lower , therefore, is consistent with decreasing in the polar direction. We label the standard MRI-driven explosion model with as the h -model, indicating neutrino heating is dominant, while the case of the magnetically driven jet with is named as the m -model. We choose the case of as a typical intermediate explosion model as the i -model. As the behavior of the explosion varies gradually depending on , the distinction of models has uncertainties, e.g., the m -model can be categorized in the i -model as an extreme case. We adopt and 0.75 models as a variation of the i -model, denoted by i -model(−) and i -model(+), respectively. The h -model(+) and m -model(+), based on and 0.40, respectively, are also referred to in order to discuss the impact of neutrino absorption. The , entropy ( S ), and for the selected models are shown in Figure 2 , when the shock front reaches ∼1000 km. For the m -model, we