Unraveling the Role of Neutrino Processes on the Astrophysical Production of ⁹⁴Mo

Abstract The enigmatic origin of the proton-rich nuclei 92 Mo and 94 Mo in the solar system remains one of the most intriguing mysteries in astrophysics, with the definitive production site yet to be identified. Although mechanisms such as the proton-capture reactions, photonuclear reactions, and neutrino processes have been proposed, the underproduction of 94 Mo persists as a puzzle. In this study, we investigate the production of 94 Mo through neutrino-induced processes during core-collapse supernova explosions. By calculating the cross sections of the charged-current reactions 94 Zr ( ν e , e − ) 94 Nb and 95 Mo ( ν e , e − p) 94 Mo, as well as the neutral-current reactions 95 Mo <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mspace width="0.25em"/> <mml:mo stretchy="false">(</mml:mo> <mml:mi>ν</mml:mi> <mml:mo>,</mml:mo> <mml:msup> <mml:mrow> <mml:mi>ν</mml:mi> </mml:mrow> <mml:mrow> <mml:mo accent="true">′</mml:mo> </mml:mrow> </mml:msup> </mml:math> n) 94 Mo, based on supernova explosion models, we explore the contribution of neutrino-nucleus reactions to the abundance of 94 Mo. Our results indicate that these neutrino-induced reactions can account for up to 6.8% of the solar system abundance of 94 Mo. Additionally, we propose that specific temperatures and proton number densities formed by neutrino shock waves could reproduce the solar system abundance ratio of 94 Mo to 92 Mo. This work provides a new perspective on understanding the origin of p -process nuclei in the solar system and establishes a significant theoretical foundation for future research endeavors.