Higgs Boson Pair Production Research Articles

Full one-loop supersymmetric corrections to charged Higgs boson pair production inγγcollisions

The complete one-loop electroweak corrections to charged Higgs boson pair production in $\ensuremath{\gamma}\ensuremath{\gamma}$ collision mode at linear colliders in the minimal supersymmetric standard model (MSSM), are calculated in this paper. We discuss the dependence of the corrections to the subprocess $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{H}^{+}{H}^{\ensuremath{-}}$ on the related parameters, such as the colliding energy, charged Higgs boson mass ${M}_{{H}^{\ifmmode\pm\else\textpm\fi{}}}$ and some supersymmetric parameters $\mathrm{tan}\ensuremath{\beta}$, ${M}_{\mathrm{SUSY}}$ and gaugino mass parameter ${M}_{2}$. We find that the corrections generally reduce the Born cross sections and the relative one-loop corrections to both the subprocess typically in the range of $\ensuremath{-}10%$ to $\ensuremath{-}30%$. We also present the numerical results at the SPS1a' point from the supersymmetry parameter analysis (SPA) project. We conclude that the full one-loop electroweak corrections to subprocess $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{H}^{+}{H}^{\ensuremath{-}}$ and the parent process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{H}^{+}{H}^{\ensuremath{-}}$ are significant and therefore should be considered in precise analysis of charged Higgs boson pair productions via $\ensuremath{\gamma}\ensuremath{\gamma}$ collision at future linear colliders.

Charged Higgs boson pairs at the CERN LHC

We compute the cross section for pair production of charged Higgs bosons at the LHC and compare the three production mechanisms. The bottom-parton scattering process is computed to next-to-leading order (NLO), and the validity of the bottom-parton approach is established in detail. The light-flavor Drell-Yan cross section is evaluated at NLO as well. The gluon-fusion process through a one-loop amplitude is then compared with these two results. We show how a complete sample of events could look, in terms of total cross sections and distributions of the heavy final states.

A Search for Doubly Charged Higgs Boson Pair Production in the Muon Channel at DØ

Several theories predict the existence of light doubly charged Higgs bosons (H±±). A search for the pair production of H±± using the DØ detector is described, assuming a 100% branching ratio to muons. In the absence of signal, limits at 95% confidence level, of 118.4 GeV and 98.2 GeV are set for left-handed and right-handed doubly charged Higgs bosons respectively.

Next-to-leading order QCD predictions for pair production of neutral Higgs bosons at the CERN Large Hadron Collider

We present the calculations of the complete next-to-leading-order (NLO) inclusive total cross sections for pair production of neutral Higgs bosons through $b\overline{b}$ annihilation in the minimal supersymmetric standard model at the CERN Large Hadron Collider. In our calculations, we used both the dimensional regularization scheme and the dimensional reduction scheme and found that the NLO total cross sections in these two schemes are the same. Our results show that the $b\overline{b}$-annihilation contributions can exceed those of $gg$ fusion and $q\overline{q}$ annihilation for ${h}^{0}{H}^{0}$, ${A}^{0}{h}^{0}$, and ${A}^{0}{H}^{0}$ productions when $\mathrm{tan}\ensuremath{\beta}$ is large. In the case of $\ensuremath{\mu}>0$, the NLO corrections enhance the leading-order total cross sections significantly, reaching a few tens of percent, while for $\ensuremath{\mu}<0$, the corrections are relatively small, and are negative in most of parameter space. Moreover, the NLO QCD corrections reduce the dependence of the total cross sections on the renormalization/factorization scale, especially for $\ensuremath{\mu}<0$. We also used the CTEQ6.1 parton distribution function sets to estimate the uncertainty of leading-order and NLO total cross sections, and found that the uncertainty arising from the choice of parton distribution functions increases with the increasing ${m}_{{A}^{0}}$.

Pair production of charged Higgs bosons from bottom-quark fusion

For very large values of $\tan\beta$, charged Higgs boson pair production at the Large Hadron Collider (LHC) from the scattering of two bottom quarks can proceed dominantly. We investigated the cross sections of charged Higgs boson pair production via the subprocess $b\bar{b} \to H^+H^-$ at the LHC including the next-to-leading order (NLO) QCD corrections in the minimal supersymmetric standard model (MSSM). We find that the NLO QCD corrections can significantly reduce the dependence of the cross sections on the renormalization and factorization scales.

Testing soft electroweak supersymmetry breaking from neutralino, chargino, and charged Higgs boson pair production at linear colliders

We consider the production of neutralino, chargino, and charged Higgs boson pairs in the Minimal Supersymmetric Standard Model (MSSM) framework at future ${e}^{+}{e}^{\ensuremath{-}}$ colliders. We show that, for c.m. energies in the 1 TeV range and in a moderately light supersymmetry (SUSY) scenario, a combined analysis of the slopes of these production cross sections could lead to a strong consistency test involving the soft supersymmetric breaking parameters ${M}_{1}$, ${M}_{2}$, the Higgsino parameter $\ensuremath{\mu}$, and $\mathrm{tan}\ensuremath{\beta}$.

Search for Doubly Charged Higgs Boson Pair Production in the Decay toμ+μ+μ−μ−inpp¯Collisions ats=1.96 TeV

A search for pair production of doubly-charged Higgs bosons in the process p pbar to H++H-- to mu+mu+mu-mu- is performed with the D0 Run II detector at the Fermilab Tevatron. The analysis is based on a sample of inclusive di-muon data collected at an energy of sqrt{s}=1.96 TeV, corresponding to an integrated luminosity of 113 pb-1. In the absence of a signal, 95 % confidence level mass limits of M(H++L)>118.4 GeV/c2 and M(H++R)>98.2 GeV/c2 are set for left-handed and right-handed doubly-charged Higgs bosons, respectively, assuming 100% branching into muon pairs.

Higgs boson pair production in the little Higgs model at hadron colliders

The Higgs boson pair production process at hadron collider provides an opportunity for performing a study of the trilinear Higgs boson self-coupling. In this paper, we analyze the pair production of a neutral Higgs boson via both gluon-gluon and $b\ensuremath{-}\overline{b}$ fusions in the littlest Higgs (LH) model at the CERN LHC. We find that in some parameter space the relative corrections of the total cross section to the SM prediction may reach a value of 24% when ${x(=4\mathrm{fv}}^{\ensuremath{'}}{/v}^{2})=0.95$ at the LHC. We conclude that if the parameter x has a value above 0.8, the relative corrections contributed by the LH model reach values beyond 8% and could be observed at the LHC.

Supersymmetry tests from a combined analysis of a chargino and charged Higgs boson pair production at a 1 TeV linear collider

We consider the production of chargino and charged Higgs boson pairs at future linear colliders for c.m. energies in the one TeV range. Working in the MSSM under the assumption of a "moderately" light SUSY scenario, we compute the leading (double) and next-to leading (linear) supersymmetric logarithmic terms of the so-called "Sudakov expansion" at one loop. We show that a combined analysis of the slopes of the chargino and of the charged Higgs production cross sections would offer a simple possibility for determining $\tan\beta$ for large ($\gtrsim 10$) values and an allowed strip in the ($M_2,\mu$) plane. This could provide a strong consistency test of the considered supersymmetric model.

Probing the Higgs self-coupling at hadron colliders using rare decays

We investigate Higgs boson pair production at hadron colliders for Higgs boson masses m_H\leq 140 GeV and rare decay of one of the two Higgs bosons. While in the Standard Model the number of events is quite low at the LHC, a first, albeit not very precise, measurement of the Higgs self-coupling is possible in the gg -> HH -> b\bar{b}\gamma\gamma channel. A luminosity-upgraded LHC could improve this measurement considerably. A 200 TeV VLHC could make a measurement of the Higgs self-coupling competitive with a next-generation linear collider. In the MSSM we find a significant region with observable Higgs pair production in the small \tan\beta regime, where resonant production of two light Higgs bosons might be the only hint at the LHC of an MSSM Higgs sector.

Neutral Higgs Boson Pair Production in Standard Model with the Fourth Generation Quarks at LHC**The project supported in part by National Natural Science Foundation of China

We investigated the neutral Higgs boson pair production at the CERN Large Hadron Collider (LHC) in the SM with four families. We found that the gluon-gluon fusion mode is the most dominant one in producing neutral Higgs boson pair at the LHC, and it can be used to probe the trilinear Higgs coupling. If the heavy quarks of the fourth generation really exist within the SM, they can manifest their effect on the cross section of the Higgs pair production process at the LHC. Our numerical results show that there will be neutral Higgs boson pair production events per year if the next generation heavy quarks really exist, while there will be only events produced per year if there are only three families in the SM.

Note on doubly charged Higgs boson pair production at hadron colliders

We analyze the next-to-leading order QCD corrections to the production of doubly-charged Higgs particles at hadron colliders in extensions of the SM with Higgs isospin triplets. At both the Tevatron and the LHC, these corrections are found to be moderate in size increasing the cross sections by about 20--30%. The residual theoretical uncertainties are of the order of 10--15% which is sufficient for experimental searches for these particles at the Tevatron and LHC.

SUDAKOV EXPANSIONS AT ONE-LOOP AND BEYOND FOR CHARGED SCALAR AND FERMION PAIR PRODUCTION IN SUSY MODELS AT FUTURE LINEAR COLLIDERS

We consider the high energy behavior of the amplitudes for pair production of charged leptons, quarks, Higgs bosons, sleptons, squarks and charginos at lepton colliders. We give the general expressions of the leading quadratic and subleading linear logarithms that appear at the one-loop level, and derive the corresponding resummed expansions to subleading logarithmic order accuracy. Under the assumption of a relatively light SUSY scenario and choosing the MSSM as a specific model, we compare the predictions of the one-loop and of the resummed expansions at variable energy. We show that the two predictions are very close in the one TeV regime, but drastically differ in the few (2,3) TeV range.

Search for doubly-charged Higgs bosons at LEP

Doubly-charged Higgs bosons are searched for in e+e− collision data collected with the L3 detector at LEP at centre-of-mass energies up to 209 GeV. Final states with four leptons are analysed to tag the pair-production of doubly-charged Higgs bosons. No significant excess is found and lower limits at 95% confidence level on the doubly-charged Higgs boson mass are derived. They vary from 95.5 to 100.2 GeV, depending on the decay mode. Doubly-charged Higgs bosons which couple to electrons would modify the cross section and forward–backward asymmetry of the e+e−→e+e− process. The measurements of these quantities do not deviate from the Standard Model expectations and doubly-charged Higgs bosons with masses up to the order of a TeV are excluded.

Examining the Higgs boson potential at lepton and hadron colliders: A comparative analysis

We investigate inclusive Standard Model Higgs boson pair production at lepton and hadron colliders for Higgs boson masses in the range 120 GeV < m_H < 200 GeV. For m_H < 140 GeV we find that hadron colliders have a very limited capability to determine the Higgs boson self-coupling, \lambda, due to an overwhelming background. We also find that, in this mass range, supersymmetric Higgs boson pairs may be observable at the LHC, but a measurement of the self coupling will not be possible. For m_H > 140 GeV we examine ZHH and HH nu bar-nu production at a future e+e- linear collider with center of mass energy in the range of sqrt{s}=0.5 - 1 TeV, and find that this is likely to be equally difficult. Combining our results with those of previous literature, which has demonstrated the capability of hadron and lepton machines to determine \lambda in either the high or the low mass regions, we establish a very strong complementarity of these machines.

The $\gamma \gamma \rightarrow H^0 H^0$ decay in non-commutative quantum electrodynamics

We study the possibility of detecting noncommutative QED through neutral Higgs boson pair production at (gamma--gamma) collider. This is based on the assumption that H^0 interacts directly with photon as suggested by symmetry considerations. The sensitivity of the cross-section to the noncommutative scale (Lambda_{NC}) and Higgs mass is investigated.

Determining the Higgs boson self-coupling at hadron colliders

Inclusive Standard Model Higgs boson pair production at hadron colliders has the capability to determine the Higgs boson self-coupling, lambda. We present a detailed analysis of the gg\to HH\to (W^+W^-)(W^+W^-)\to (jjl^\pm\nu)(jj{l'}^\pm\nu) and gg\to HH\to (W^+W^-)(W^+W^-)\to (jjl^\pm\nu)({l'}^\pm\nu {l''}^\mp\nu) (l, {l'}, {l''}=e, \mu) signal channels, and the relevant background processes, for the CERN Large Hadron Collider, and a future Very Large Hadron Collider operating at a center-of-mass energy of 200 TeV. We also derive quantitative sensitivity limits for lambda. We find that it should be possible at the LHC with design luminosity to establish that the Standard Model Higgs boson has a non-zero self-coupling and that lambda / lambda_{SM} can be restricted to a range of 0-3.8 at 95% confidence level (CL) if its mass is between 150 and 200 GeV. At a 200 TeV collider with an integrated luminosity of 300 fb^{-1}, lambda can be determined with an accuracy of 8 - 25% at 95% CL in the same mass range.

Measuring the Higgs boson self-coupling at the Large Hadron Collider.

Inclusive standard model Higgs boson pair production and subsequent decay to same-sign dileptons via weak gauge W+/- bosons at the CERN Large Hadron Collider (LHC) has the capability to determine the Higgs boson self-coupling, lambda. The large top quark mass limit is found not to be a good approximation for the signal if one wishes to utilize differential distributions in the analysis. We find that it should be possible at the LHC with design luminosity to establish that the standard model Higgs boson has a nonzero self-coupling and that lambda/lambda(SM) can be restricted to a range of 0-3.7 at 95% confidence level if its mass is between 150 and 200 GeV.

Pair production of charged Higgs scalars from electroweak gauge boson fusion

We compute the contribution to charged Higgs boson pair production at the large hadron collider (LHC) due to the scattering of two electroweak (EW) gauge bosons, these being in turn generated via bremsstrahlung of incoming quarks: qq → qqV*V* → qqH+H− (V = γ, Z, W±). We verify that the production cross section of this mode is tan β independent and show that it is smaller than that of H+H− production via qq-initiated processes, but generally larger than that of the loop-induced channel gg → H+H−. Pair production of charged Higgs bosons is crucial in order to test EW symmetry breaking scenarios beyond the standard model. We show that the detection of these kinds of processes at the standard LHC is, however, problematic, because of their poor production rates and large backgrounds.

Pair production of neutral Higgs bosons through noncommutative QED interactions at linear colliders

We study the feasibility of detecting noncommutative (NC) QED through neutral Higgs boson (H) pair production at linear colliders (LC). This is based on the assumption that H interacts directly with photon in NCQED as suggested by symmetry considerations and strongly hinted by our previous study on ${\ensuremath{\pi}}^{0}$-photon interactions. We find the following striking features as compared to the standard model (SM) result: (1) generally larger cross sections for an NC scale of order 1 TeV; (2) completely different dependence on initial beam polarizations; (3) distinct distributions in the polar and azimuthal angles; and (4) day-night asymmetry due to the Earth's rotation. These will help to separate NC signals from those in the SM or other new physics at LC. We emphasize the importance of treating properly the Lorentz noninvariance problem and show how the impact of the Earth's rotation can be used as an advantage for our purpose of searching for NC signals.