Constraining the variation of fundamental constants with tritium decays




Fradette, Anthony

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The consistency of fundamental constants is assumed in the Standard Model. However, new physics theories allow them to be dynamical. Different tests can be made at various epochs of the universe. In particular, current bounds at the time of emission of the Cosmic Microwave Background (CMB) permit variations up to 1% of their present values. A change of this order can produce an accumulation of tritium which would later decay and modify the ionization history of the Universe by up to O(0.1%). This Tritium Decay Scenario (TDS) can modify the CMB to an observable level and thus provides a new probe of Varying Fundamental Constants (VFC). We analyze the WMAP 7-year and SPT data with respect to the TDS and find no evidence for VFC. The data disfavors a portion of the parameter space at 95% Confidence Level (CL). We forecast the sensitivity of Planck to the TDS and find that a larger range of parameters can be excluded at 3σ CL.



Theoretical Physics, Particle Physics, Cosmology