J Balibrea-Correa, J Lerendegui-Marco, C Domingo-Pardo, V Babiano-Suarez, I Ladarescu, M Krtička, G Cescutti, S Cristallo, D Vescovi, N Liu, E A Maugeri, U Köster, I Mönch, A Casanovas, V Alcayne, D Cano-Ott, E Mendoza, O Aberle, J Andrzejewski, S Altieri, S Amaducci, M Bacak, C Beltrami, S Bennett, A P Bernardes, E Berthoumieux, R Beyer, M Boromiza, D Bosnar, M Caamaño, F Calviño, M Calviani, D M Castelluccio, F Cerutti, S Chasapoglou, E Chiaveri, P Colombetti, N Colonna, P Console Camprini, G Cortés, M A Cortés-Giraldo, L Cosentino, S F Dellmann, M Diakaki, M Di Castro, M Dietz, S Di Maria, R Dressler, E Dupont, I Durán, Z Eleme, S Fargier, B Fernández, B Fernández-Domínguez, P Finocchiaro, S Fiore, V Furman, F García-Infantes, A Gawlik-Ramięga, G Gervino, S Gilardoni, E González-Romero, C Guerrero, F Gunsing, C Gustavino, J Heyse, W Hillman, D G Jenkins, E Jericha, A Junghans, Y Kadi, K Kaperoni, G Kaur, A Kimura, I Knapová, M Kokkoris, Y Kopatch, N Kyritsis, C Lederer-Woods, G Lerner, A Manna, T Martínez, A Masi, C Massimi, P Mastinu, M Mastromarco, A Mazzone, A Mengoni, V Michalopoulou, P M Milazzo, R Mucciola, F Murtas, E Musacchio González, A Musumarra, A Negret, N Patronis, J A Pavón, M G Pellegriti, P Pérez-Maroto, A Pérez de Rada Fiol, J Perkowski, C Petrone, E Pirovano, J Plaza Del Olmo, S Pomp, I Porras, J Praena, J M Quesada, R Reifarth, D Rochman, Y Romanets, C Rubbia, A Sánchez-Caballero, M Sabaté-Gilarte, P Schillebeeckx, D Schumann, A Sekhar, A G Smith, N V Sosnin, M E Stamati, A Sturniolo, G Tagliente, A Tarifeño-Saldivia, D Tarrío, P Torres-Sánchez, S Urlass, E Vagena, S Valenta, V Variale, P Vaz, G Vecchio, V Vlachoudis, R Vlastou, A Wallner, P J Woods, T Wright, R Zarrella, P Žugec, n_TOF Collaboration
Isotopic measurements of presolar silicon carbide grains from dying stars have revealed a puzzling overabundance of ^{94}Mo that stellar nucleosynthesis models have failed to reproduce for two decades. This discrepancy challenged our understanding of the slow neutron-capture process (s-process) that forges approximately half of the elements heavier than iron. The key uncertainty lies at ^{94}Nb, a radioactive branching point where competition between neutron capture and beta decay governs the ^{94}Mo production, yet the neutron-capture cross section had never been measured. Here, we report the first experimental determination of the ^{94}Nb(n,γ)^{95}Nb cross section important for Mo isotopic abundances. The measurement was enabled by a coordinated effort involving high-purity target preparation at Institute of Solid State and Materials Research Dresden, radioactive sample production at the Institut Laue-Langevin Grenoble, radiochemical characterization at Paul Scherrer Institut Villigen, and the time-of-flight CERN n_TOF facility using for the first time segmented total-energy detectors. Incorporation of the resulting Maxwellian-averaged cross section into fully coupled nucleosynthesis models of low-mass asymptotic giant-branch stars brings them into agreement with the presolar grain data. These results remove a major nuclear-physics input uncertainty at the ^{94}Nb branching point and provide a firmer foundation for understanding the origin of ^{94}Mo in the Solar System.