$R_{D^{(*)}}$ anomaly: A possible hint for natural supersymmetry with $R$-parity violation

Recently, several $B$-physics experiments have reported an appreciable deviation from the standard model (SM) in the tree-level observables $R_{D^{(*)}}$; the combined weighted average now stands at $\approx 4\sigma$. We first show the anomaly necessarily implies model-independent collider signals of the form $pp\to b\tau \nu$ that should be expeditiously searched for at ATLAS/CMS as a complementary test of the anomaly. Next we suggest a possible interconnection of the anomaly with the radiative stability of the standard model Higgs boson and point to a minimal effective supersymmetric scenario with $R$-parity violation as the underlying cause. We also comment on the possibility of simultaneously explaining the recently reported $R_{K^{(*)}}$ anomaly in this setup.

Figure 1

Normalized kinematic distributions for the $pp\to b\tau \nu \to b\ell +{\cancel{E}}_T$ signal and background.

Figure 2

RG evolution of the gauge couplings in the SM, MSSM and in our natural RPV SUSY scenario.

Figure 3

RPV parameter space satisfying the $R_{D^{(*)}}$ anomaly and other relevant constraints.

Figure 4

The SM predictions (red), experimental world average (green), and accessible values in our RPV-SUSY scenario (blue) in the $R_D$ vs. $R_{D^{*}}$ plane. For the SM, bearing in mind recent works [17, 20, 22] we are taking ($R_D^{\mathrm{SM}},R_{D^{*}}^{\mathrm{SM}})=(0.299\pm 0.011,0.260\pm 0.010)$.