We report anomalously large shot noise in metallic and tunnel nanojunctions of $\beta$-tantalum, a metal characterized by a small negative temperature coefficient of resistivity inconsistent with both the Fermi liquid theory of Bloch electrons and single-particle localization. Fano factors are enhanced, and cluster around even multiples of the values expected for Fermi liquids, suggesting the possibility of pairwise electron correlations akin to local groups of Cooper pairs. The importance of spin for this state is suggested by the effects of magnetic impurities. Additional evidence for correlations is provided by the reduced density of states near the Fermi level revealed by point contact spectroscopy and first principles calculations. Our findings indicate that electron correlations may play an important role in a much larger class of materials than previously believed.

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• Electronic structure
• Pairing mechanisms
• Strongly correlated systems
• Noise measurements