Cosmological birefringence due to CPT-even Chern–Simons-like term with Kalb–Ramond and scalar fields

We study the CPT-even dimension-six Chern–Simons-like term by including dynamical Kalb–Ramond and scalar fields to examine the cosmological birefringence. We show that the combined effect of a neutrino current and a Kalb–Ramond field could induce a sizable rotation polarization angle in the cosmic microwave background radiation polarization

Explaining AMS-02 positron excess and muon anomalous magnetic moment in dark left-right gauge model

In a Dark left-right gauge model, the neutral component of right-handed lepton doublet is odd under generalized R-parity and thus the lightest one serves as the dark matter (DM) candidate. The coannihilation of the dark matter with the singly charged Higgs triplet produces the correct relic abundance. We explain AMS-02 positron excess by the annihilation of 800 GeV dark matter into μ + μ −γ, through a t-channel exchange of the additional charged triplet Higgs boson. The DM is leptophilic which is useful for explaining the non-observation of any antiproton excess which would generically be expected from DM annihilation. The large cross-section needed to explain AMS-02 also requires an astrophysical boost. In addition, we show that the muon (g − 2) receives required contribution from singly and doubly charged triplet Higgs in the loops.by Tanushree Basak, Subhendra Mohanty and Gaurav Toma