Radion-Higgs mixing in 2HDMs

Abstract

We study the custodial Randall-Sundrum model with two Higgs doublets localized in the TeV brane. The scalar potential is CP-conserving and has a softly broken Z 2 symmetry. In the presence of a curvature-scalar mixing term ξ ab RΦ † a Φ b the radion that stabilizes the extra dimension now mixes with the two CP-even neutral scalars h and H. A goodness of fit of the LHC data on the properties of the light Higgs is performed on the parameter space of the type-I and type-II models. LHC direct searches for heavy scalars in different decay channels can help distinguish between the radion and a heavy Higgs. The most important signatures involve the ratio of heavy scalar decays into b quark pairs to those into Z pairs, as well as the decay of the scalar (pseudoscalar) into a Z plus a pseudoscalar (scalar).

Photoproduction of mixed radions at a proton–proton collider

“…Although it is experimentally difficult to discern radion from Higgs boson, a detailed analysis shows that the observed new scalar is likely to be the SM Higgs instead of RS radion [4,5] 6 . However, similarities between SM Higgs and RS radion are remarkable and lead us to think about an interesting scenario called Higgs-radion mixing [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. According to this scenario the Higgs boson can mix with a radion field and constitute two physical mixed states.…”