Charged Higgs production in association with $W^{\pm }$ at large hadron colliders

Many new physics models beyond the standard model, such as the littlest Higgs models and the left-right twin Higgs models, predict the existence of the large charged Higgs couplings $H^{-}q\overline{b}$ and $H^{+}b\overline{q}$, where $q=t$ or the new vectorlike heavy quark $T$. On the other hand, some new physics models, like the littlest Higgs, also predict the gauge-Higgs couplings. Such couplings may have rich collider phenomenology. We focus our attention on these couplings induced by the littlest Higgs models and the left-right twin Higgs models and consider their contributions to the production cross section for $W^{\pm }{H}^{\mp }$ production at the large hadron colliders. We find that the cross sections in the littlest Higgs models on the parton level $gg\to W^{\pm }{H}^{\mp }$ and $q\overline{q}\to W^{\pm }{H}^{\mp }$ ($q=u$, $d$, $s$, $c$, $b$) may reach tens of dozens femtobarns in reasonable parameter space at the collision energy of 14 TeV and that the total cross section can even reach a few hundred femtobarns in certain favored space. While in the left-right twin Higgs models, the production rates are basically one order lower than those in the littlest Higgs models. Therefore, due to the large cross sections of that in the littlest Higgs models, it may be possible to probe the charged Higgs via this process in a certain parameter space.

Figure 1

In the LH, the contour of the parameters $f$ and $s$ for the lower limit of the new heavy gauge boson mass $M_{Z_H}=1620\mathrm{TeV}$.

Figure 2

Feynman diagrams for the charged scalar production associated with the $W$ boson at the LHC via gluon fusion (a),(b),(c) and the quark antiquark annihilation (d),(e) parton level processes in the LH model. Those obtained by exchanging the two external gluon lines are not displayed here.

Figure 3

In the LH, the cross section $\sigma$ of the processes $gg\to {\varphi }^{+}{W}^{-}$ as a function of the scalar mass $m_{\varphi }$ with the center-of-mass energy $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and 14 TeV (b), respectively, for $f=500\mathrm{GeV}$ and $s=0.1$, with different $x$ ($x=0$, 0.05, 0.1, 0.2); the cross section $\sigma$ of the processes $gg\to {\varphi }^{+}{W}^{-}$ as a function of $f$ with $E_{\mathrm{cm}}=8\mathrm{TeV}$ (c) and 14 TeV (d), respectively, and $s=0.1$, with different $x$ ($x=0$, 0.05, 0.1, 0.2).

Figure 4

In the LH, when the scalar mass $m_{\varphi }=200$, 400, 600 GeV, the cross section $\sigma$ of the processes $gg\to {\varphi }^{+}{W}^{-}$ as a function of $x$ with $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and 14 TeV (b), respectively, and $s=0.1$, with $f=500\mathrm{GeV}$. The cross section $\sigma$ of the processes $gg\to {\varphi }^{+}{W}^{-}$ as a function of $s$ for $x=0.1$, $f=500\mathrm{GeV}$, and $E_{\mathrm{cm}}=8$ and 14 TeV (c).

Figure 5

In the LH, the cross section $\sigma$ of the processes $q\overline{q}\to {\varphi }^{+}{W}^{-}$ as a function of the scalar mass $m_{\varphi }$ with $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and 14 TeV (b) for $f=500\mathrm{GeV}$, $x=0.1$, and $s=0.1$. The $q\overline{q}\to {\varphi }^{+}{W}^{-}$ cross section $\sigma$ as a function of $f$ with $E_{\mathrm{cm}}=8\mathrm{TeV}$ (c) and 14 TeV (d), respectively, and $s=0.1$, $x=0.1$. Here $q=u$, $d$, $c$, $s$, $b$ quarks.

Figure 6

In the LH, the cross section $\sigma$ of the processes $q\overline{q}\to {\varphi }^{+}{W}^{-}$, with $m_{\varphi }=200\mathrm{GeV}$, $f=500\mathrm{GeV}$ as a function of $x$ for $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and 14 TeV (b) ($s=0.1$).

Figure 7

In the LH models, the total cross section $\sigma$ of the processes $pp\to {\varphi }^{+}{W}^{-}$ as a function of the scalar mass $m_{\varphi }$ with $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and 14 TeV (b) for $s=0.1$, $f=500\mathrm{GeV}$, and $x=0$, 0.05, 0.1, 0.2. The total cross section $\sigma$ of the processes $pp\to {\varphi }^{+}{W}^{-}$ as a function of $f$ with the scalar mass $m_{\varphi }=200\mathrm{GeV}$, $s=0.1$ and $E_{\mathrm{cm}}=8\mathrm{TeV}$ (c) and $E_{\mathrm{cm}}=14\mathrm{TeV}$ (d) for $x=0$, 0.05, 0.1, 0.2.

Figure 8

The total cross section $\sigma$ of the processes $pp\to {\varphi }^{+}{W}^{-}$ as a function of $x$ with the scalar mass $m_{\varphi }=200$, 400, 600 GeV, $s=0.1$, and $E_{\mathrm{cm}}=8\mathrm{TeV}$ (a) and $E_{\mathrm{cm}}=14\mathrm{TeV}$ (b).

Figure 9

In the LRTH, the cross section $\sigma$ of the processes $gg\to {\varphi }^{+}{W}^{-}$ as a function of the scalar mass $m_{\varphi }$ (a),(b) or $f$ (c),(d) with $E_{\mathrm{cm}}=8\mathrm{TeV}$ and $E_{\mathrm{cm}}=14\mathrm{TeV}$ for $M=100$, 300, 500 GeV.

Figure 10

In the LRTH, the cross section $\sigma$ of the processes $q\overline{q}\to {\varphi }^{+}{W}^{-}$ as a function of $m_{\varphi }$ or $f$ for $M=100$, 300, 500 GeV with the scalar mass $m_{\varphi }=200\mathrm{GeV}$ and $E_{\mathrm{cm}}=8\mathrm{TeV}$ and $E_{\mathrm{cm}}=14\mathrm{TeV}$.

Figure 11

In the LRTH, the total cross section $\sigma$ of the processes ${\varphi }^{+}{W}^{-}$ associated production from $gg$ fusion and $b\overline{b}$ collision as a function of the scalar mass $m_{\varphi }$ (a),(b) or $f$ (c),(d) with $E_{\mathrm{cm}}=8\mathrm{TeV}$ and $E_{\mathrm{cm}}=14\mathrm{TeV}$ for $f=500$, 1000 GeV for different $M$ ($M=100$, 300, 500 GeV).