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In this work, we explore the effect of neutrino nonstandard interactions (NSI) involving the charm quark at SND@LHC. Using an effective description of new physics in terms of four-fermion operators involving a charm quark, we constrain the Wilson coefficients of the effective interaction from two and three-body charmed meson decays. In our fit, we include charmed meson decays not only to pseudoscalar final states but also to vector final states and include decays to the η and η′ final states. We also consider constraints from charmed baryon decays. We then study the effect of new physics in neutrino scattering processes, involving charm production at SND@LHC, for various benchmark new physics couplings obtained from the low energy fits. Finally, we also study the effects of lepton universality violation (LUV) assuming that the new physics coupling is not lepton universal.
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Probes of non-standard interactions from exclusive hadronic tau decays
In this talk we study the sensitivity of exclusive hadronic tau decays to non-standard interactions using the low-energy limit of the Standard Model Effective Field Theory. Employing Lattice input and dispersive form factors, along with experimental data, we analyze both one and two meson decays to set bounds on the new physics effective couplings. Our results complement the traditional low-energy probes, such as nuclear β or Kℓ3 decays, and can be improved with new data, e.g. from Belle-II.
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- Award ID(s):
- 1714253
- PAR ID:
- 10335302
- Date Published:
- Journal Name:
- PoS CHARM2020 (2021) 044
- Page Range / eLocation ID:
- 044
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.22323/1.385.0044
