Confronting the vector leptoquark hypothesis with new low- and high-energy data
Jason Aebischer, Gino Isidori, Marko Pesut, Ben A. Stefanek, Felix Wilsch
Abstract
Abstract In light of new data we present an updated phenomenological analysis of the simplified $$U_1$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>U</mml:mi> <mml:mn>1</mml:mn> </mml:msub> </mml:math> -leptoquark model addressing charged-current B -meson anomalies. The analysis shows a good compatibility of low-energy data (dominated by the lepton flavor universality ratios $$R_D$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>R</mml:mi> <mml:mi>D</mml:mi> </mml:msub> </mml:math> and $$R_{D^*}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>R</mml:mi> <mml:msup> <mml:mi>D</mml:mi> <mml:mo>∗</mml:mo> </mml:msup> </mml:msub> </mml:math> ) with the high-energy constraints posed by $$pp\rightarrow \tau {\bar{\tau }}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>p</mml:mi> <mml:mi>p</mml:mi> <mml:mo>→</mml:mo> <mml:mi>τ</mml:mi> <mml:mover> <mml:mrow> <mml:mi>τ</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> </mml:mrow> </mml:math> Drell-Yan data. We also show that present data are well compatible with a framework where the leptoquark couples with similar strength to both left- and right-handed third-generation fermions, a scenario that is well-motivated from a model building perspective. We find that the high-energy implications of this setup will be probed at the 95% confidence level in the high-luminosity phase of the LHC.