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DOE OSTI ยท 2525976

Unique Forbidden Beta Decays at Zero Momentum Transfer

Seng, Chien-Yeah [Michigan State University, East Lansing, MI (United States); University of Washington, Seattle, WA (United States)] (ORCID:0000000230620118)ยทGlick-Magid, Ayala [University of Washington, Seattle, WA (United States)] (ORCID:0000000344998303)ยทCirigliano, Vincenzo [University of Washington, Seattle, WA (United States)] (ORCID:000000029056754X)
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Abstract

We report an exploratory study of the ๐’ชโก(๐›ผ) structure-dependent electromagnetic radiative corrections to unique first-forbidden nuclear beta decays. We show that the insertion of angular momentum into the nuclear matrix element by the virtual or real photon exchange opens up the decay at vanishing nuclear recoil momentum which was forbidden at tree level, leading to a dramatic change in the decay spectrum not anticipated in existing studies. We discuss its implications for precision tests on the standard model and searches for new physics.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSBeta decayElectroweak interactions in nuclear physicsElectroweak radiative corrections

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Seng, Chien-Yeah [Michigan State University, East Lansing, MI (United States); University of Washington, Seattle, WA (United States)] (ORCID:0000000230620118), Glick-Magid, Ayala [University of Washington, Seattle, WA (United States)] (ORCID:0000000344998303), Cirigliano, Vincenzo [University of Washington, Seattle, WA (United States)] (ORCID:000000029056754X). 2025-02-28. Unique Forbidden Beta Decays at Zero Momentum Transfer. https://doi.org/10.1103/physrevlett.134.081805

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