= Heavy Scalar Effective Model =

== Authors ==

- Yongcheng Wu (contact for inquiries)
    - ycwu -at- physics.carleton.ca,  Carleton University
- Yue Xu 
    - yue.xu -at- cern.ch, Tsinghua University
- Xin Chen
    - xin.chen -at- cern.ch, Tsinghua University

== Model Description ==

In addition to the SM particle contents, we add one heavy scalar which might come from the second doublet etc. We focus on the effective couplings to the vector bosons, which are related to EWSB, and add following operators with both dim-6 and dim-4:

{{{#!latex
\begin{align*}
    \mathcal{L}_6 =& g_{6,H}^{WW} (\partial_\nu H)W^{\dagger}_{\mu} W^{\mu\nu} + h.c. + g_{6,H}^{\prime WW} H W^{\mu\nu}W^\dagger_{\mu\nu} \nonumber \\
    & + g_{6,H}^{ZZ} (\partial_\nu H) Z_\mu Z^{\mu\nu} + h.c. + g_{6,H}^{\prime ZZ} H Z^{\mu\nu}Z_{\mu\nu} +\nonumber \\
    & + g_{6,H}^{Z\gamma} (\partial_\nu H) Z_\mu F^{\mu\nu} + g_{6,H}^{\prime Z\gamma} F^{\mu\nu}Z_{\mu\nu} \nonumber \\
    & + g_{6,H}^{\gamma\gamma} H F^{\mu\nu}F_{\mu\nu}
\end{align*}
}}}
and
{{{#!latex
\begin{align*}
    \mathcal{L}_4 = g_{4,H}^{WW}g^{\mu\nu} H W^+_\mu W^-_\nu + g_{4,H}^{ZZ}g^{\mu\nu} H Z_\mu Z_\nu
\end{align*}
}}}

For more details, please check the document [https://github.com/ycwu1030/FR_Heavy_Scalar_EFT_D6/blob/master/docs/man.pdf here] and the references listed below.

== Model Files ==

=== FeynRules Model Files ===

[attachment:HeavyScalar_EFT_FR.tar.gz]: The FeynRules model files used to generate UFO files, including the files from SM.

=== UFO Model Files ===

[attachment:HeavyScalar_EFT_UFO.tar.gz]: The UFO model files generated using FeynRules (with Massless and Cabibbo restrictions)

== References ==
- Y.-P. Kuang, H.-Y. Ren, L.-H. Xia, [https://doi.org/10.1103/PhysRevD.90.115002 Phys. Rev. D90(2014) 115002] [http://arxiv.org/abs/1404.6367 arXiv:1404.6367]
- Y.-P. Kuang, H.-Y. Ren, L.-H. Xia, [https://doi.org/10.1088/1674-1137/40/2/023101 Chin.Phys.C40(2) (2016) 023101] [http://arxiv.org/abs/1506.08007 arXiv:1506.08007]
- X. Chen, Y. Xu, Y. Wu, Y.-P. Kuang, Q. Wang, H. Chen, S.-C. Hsu, Z. Hu, C. Li, [http://arxiv.org/abs/arXiv:1905.05421 arXiv:1905.05421]