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arXiv · 2606.16166

Massive right-handed neutrinos in $\bar{B} \to D^* τ\bar X$ decay

Nilakshi Das·Alakabha Datta·Tejhas Kapoor·Danny Marfatia·Lopamudra Mukherjee
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Abstract

We explore signatures of a massive right-handed neutrino (RHN) in angular distributions of $\bar{B} \to D^* (\to D π) τ(\to πν_τ) \bar X$ decays, where $X$ is an invisible state. We assume the new physics is described by the standard model effective field theory extended with an RHN in the MeV-GeV mass range. We calculate for the first time the full differential distributions in terms of the visible final states, including the decay of the $τ$ lepton. We evaluate the sensitivity of various distributions to the new physics operators.

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Nilakshi Das, Alakabha Datta, Tejhas Kapoor, Danny Marfatia, Lopamudra Mukherjee. 2026-09-13. Massive right-handed neutrinos in $\bar{B} \to D^* τ\bar X$ decay. https://doi.org/10.1007/jhep09(2026)092

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