https://arxiv.org/abs/2507.13103Reassessing the gallium anomaly using exact electron wave functionsThe gallium anomaly, a persistent discrepancy exceeding $4σ$ in the $^{71}$Ga neutrino capture rates from $^{51}$Cr and $^{37}$Ar calibration sources by the GALLEX, SAGE, and recently BEST experiments, has challenged particle physics and nuclear theory for over three decades. We present a new calculation for the neutrino capture cross-section, abandoning the conventional leading-order approximation for electronic wave functions by numerically solving the Dirac-Coulomb equation for both bound and continuum electron states. Finally, we re-evaluate the gallium anomaly, updating its global significance and presenting the most up-to-date status of its interpretation in terms of sterile neutrinos.arxiv.orgGallium anomaly라고 71 Ga 를 이용한 실험이 있었는데 3개의 서로 다른 실험에서 SM과의 tension이 확인된 상태임. 이 논문에서는 핵 근처에서 전자의 exact wavefunction을 계산해서 cross section을 개선한 건데, SM랑 간극이 4 시그마에서 최대 6.1 시그마까지 떨어졌다고 함. 대신 sterlie neutrino랑도 어느 정도 tension이 있는 결과가 나왔다는 게 상당히 흥미로운 듯.
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