Two-loop improved predictions for $$\mathbf {M_W}$$ and $$\mathbf {sin^2\theta _{eff}}$$ in Two-Higgs-Doublet models
Stephan Hessenberger, W. Hollik
Abstract
Abstract We present the currently most precise predictions for the W -boson mass and the leptonic effective mixing angle in the aligned Two-Higgs-Doublet Model. The evaluation includes the full one-loop result, all known higher-order corrections of the Standard Model, and the non-standard two-loop contributions that increase with mass splittings between charged and neutral THDM Higgs bosons. They depend on $$\tan \beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>tan</mml:mo> <mml:mi>β</mml:mi> </mml:mrow> </mml:math> and the soft $$Z_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>Z</mml:mi> <mml:mn>2</mml:mn> </mml:msub> </mml:math> -symmetry breaking parameter $$m_{12}^2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>m</mml:mi> <mml:mrow> <mml:mn>12</mml:mn> </mml:mrow> <mml:mn>2</mml:mn> </mml:msubsup> </mml:math> of the scalar potential, in addition to the non-standard boson masses. Whenever the one-loop corrections become large, the two-loop contributions yield substantial modifications of the predictions, which is of particular importance for the W mass where large mass shifts are required to reach the recently published final result of the CDF collaboration. Numerical results are shown for the dependence on the various non-standard parameters and in comparison with experimental data.