Speaker
Description
Terrestrial matter effects are small but non-negligible for JUNO-like medium-baseline reactor antineutrino program, at a level relevant to percent- to per-mille–precision determinations of the solar oscillation parameters and to the robustness of the mass-ordering measurement. In this talk I will discuss: the expected size of matter-induced spectral distortions and their impact on fits of key oscillation parameters; the potential biases and mild loss of ordering sensitivity if matter effects are neglected; and quantitative updates obtained by replacing the constant-density approximation with realistic, piecewise crust density profiles along the Taishan–JUNO and Yangjiang–JUNO baselines. I will show that profile variations mainly affect the matter contribution at a subleading level and induce only small changes in JUNO’s ordering discriminator, supporting an averaged-density treatment for current analyses while motivating controlled profile modeling for future per-mille precision and new-physics searches.
