We present the calculation of the full next-to-leading order (NLO) QCD corrections to Higgs boson pair production via gluon fusion at the LHC, including the exact top-mass dependence in the two-loop ...virtual and one-loop real corrections. This is the first independent cross-check of the NLO QCD corrections presented in the literature before. Our calculation relies on numerical integrations of Feynman integrals, stabilised with integration-by-parts and a Richardson extrapolation to the narrow width approximation. We present results for the total cross section as well as for the invariant Higgs-pair-mass distribution at the LHC, including for the first time a study of the uncertainty due to the scheme and scale choice for the top mass in the loops.
A
bstract
Now that the Higgs boson has been observed by the ATLAS and CMS experiments at the LHC, the next important step would be to measure accurately its properties to establish the details of the ...electroweak symmetry breaking mechanism. Among the measurements which need to be performed, the determination of the Higgs self-coupling in processes where the Higgs boson is produced in pairs is of utmost importance. In this paper, we discuss the various processes which allow for the measurement of the trilinear Higgs coupling: double Higgs production in gluon fusion, vector boson fusion, double Higgs-strahlung and associated production with a top quark pair. We first evaluate the production cross sections for these processes at the LHC with center-of-mass energies ranging from the present
TeV to
TeV, and discuss their sensitivity to the trilinear Higgs coupling. We include the various higher order QCD radiative corrections, at next-to-leading order for gluon and vector boson fusion and at next-to-next-to-leading order for associated double Higgs production with a gauge boson. The theoretical uncertainties on these cross sections are estimated. Finally, we discuss the various channels which could allow for the detection of the double Higgs production signal at the LHC and estimate their potential to probe the trilinear Higgs coupling.
In this paper we discuss the combination of the usual renormalization and factorization scale uncertainties of Higgs-pair production via gluon fusion with the novel uncertainties originating from the ...scheme and scale choice of the virtual top mass. Moreover, we address the uncertainties related to the top-mass definition for different values of the trilinear Higgs coupling and their combination with the other uncertainties.
We present the program package NMSSMCALC for the calculation of the loop-corrected NMSSM Higgs boson masses and decay widths in the CP-conserving and CP-violating NMSSM. The full one-loop corrections ...to the Higgs boson masses are evaluated in a mixed renormalisation scheme of on-shell and DR¯ conditions. The Higgs decay widths include the dominant higher order QCD corrections, and the decays into bottom quarks, strange quarks and τ leptons are supplemented by higher order SUSY corrections through effective couplings. All relevant off-shell decays into two massive gauge bosons, gauge and Higgs boson and Higgs pair final states as well as into heavy quark pairs are computed. The input and output files feature the SUSY Les Houches Accord so that the program can easily be linked with existing computer tools.
Program title: NMSSMCALC
Catalogue identifier: AEUE_v1_0
Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEUE_v1_0.html
Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland
Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html
No. of lines in distributed program, including test data, etc.: 53070
No. of bytes in distributed program, including test data, etc.: 329132
Distribution format: tar.gz
Programming language: Fortran77.
Computer: Any with a Fortran77 system.
Operating system: Linux, Unix.
RAM: 0.5MB
Classification: 11.1.
Nature of problem:
Computation of the NMSSM Higgs mass spectrum including higher order corrections in a mixed renormalisation scheme of on-shell and DRbar conditions, and numerical calculation of the decay widths and branching ratios, both in the CP-conserving and in the CP-violating NMSSM. The decay widths include the dominant higher order QCD corrections and, for the neutral Higgs boson decays into a bottom quark pair, the higher order SUSY–QCD and the approximate SUSY–electroweak (elw) corrections up to one-loop accuracy. The decays into a strange quark pair include the dominant resummed SUSY–QCD corrections and the one into a τ pair the dominant resummed SUSY–elw corrections. Analogously for the charged Higgs boson the higher order SUSY corrections have been implemented for the decays into fermion pairs. In the real NMSSM, the decays into stop and sbottom pairs, respectively, contain the SUSY–QCD corrections. All relevant off-shell decays into massive gauge bosons, into gauge and Higgs bosons, into Higgs pairs and into heavy quark pairs have been taken into account. The input and output files feature the SUSY Les Houches Accord (SLHA).
Solution method:
The necessary input values are set in the two input files inp.dat (in the SLHA format) and bhdecay.in. The file inp.dat, where the choice between the real and the complex NMSSM can be made, is read in by CalcMasses.F, which calculates the one-loop corrected NMSSM Higgs mass spectrum. CalcMasses.F writes out all necessary parameters, masses and mixing angles in an SLHA format file slha.in, which is read in by bhdecay.f (by bhdecay c.f in the complex case). This Fortran routine then computes the decay widths and branching ratios and writes them out in an SLHA format file slha decay.out. Furthermore it writes out all parameters and mixing angles.
Restrictions:
At present the NMSSM Higgs spectrum is calculated at one-loop accuracy, the Higgs self-couplings at leading order, and no renormalisation group running of the input parameters is included. However, we are about to implement the two-loop corrections to the NMSSM Higgs boson masses and the Higgs self-couplings. Furthermore, the renormalisation group equations for the input parameters shall be provided in the near future. The program does not provide any distributions.
Running time:
Less than one second per point
After the discovery of the Higgs boson in 2012 at the CERN Large Hadron Collider (LHC), the study of its properties still leaves room for an extended Higgs sector with more than one Higgs boson. ...2-Higgs doublet models (2HDMs) are well-motivated extensions of the Standard Model (SM) with five physical Higgs bosons: two CP-even states
h
and
H
, one CP-odd state
A
, and two charged states
H
±
. In this letter, we present the calculation of the full next-to-leading order (NLO) QCD corrections to
hH
and
AA
production at the LHC in the 2HDM at small values of the ratio of the vacuum expectation values,
tan
β
, including the exact top-mass dependence everywhere in the calculation. Using techniques applied in the NLO QCD SM Higgs pair production calculation, we present results for the total cross section as well as for the Higgs-pair-mass distribution at the LHC. We also provide the top-quark scale and scheme uncertainties which are found to be sizeable.
We present the first calculation of the one-loop corrections to the triple Higgs coupling in the framework of a simplified 3+1 Dirac neutrino model, that is three light neutrinos plus one heavy ...neutrino embedded in the Standard Model (SM). The triple Higgs coupling is a key parameter of the scalar potential triggering the electroweak symmetry-breaking mechanism in the SM. The impact of the heavy neutrino can be as large as +20% to +30% for parameter points allowed by the current experimental constraints depending on the tightness of the perturbative bound. This can be probed at the high-luminosity LHC, at future electron-positron colliders and at the Future Circular Collider in hadron-hadron mode, an envisioned 100 TeV pp machine. Our calculation, being done in the mass basis, can be extended to any model using the neutrino portal. In addition, the effects that we have calculated are expected to be enhanced if additional heavy fermions with large Yukawa couplings are included, as in low-scale seesaw mechanisms.
It has been argued that learning a second language requires more self-motivation than other courses (Horwitz, 1995). This article reviews literature on motivation in foreign language classrooms and ...discusses reasons for the lack of motivation among students in second language classes. Particular attention will be given to addressing reasons why students in Latin classrooms may have less motivation than in other classes. Specifically, intrinsic and extrinsic motivation will be discussed in terms of a Latin classroom. Additionally, this article will discuss what steps can be taken by the teacher to increase motivation and engagement through gameplay, creating a safe space to make mistakes, and turning extrinsic motivation into intrinsic motivation.
We present the first study of the production of a Standard Model Higgs boson at a lepton collider in association with a pair of
W
bosons,
e
+
e
-
→
W
+
W
-
H
, in the inverse seesaw model. Taking ...into account all relevant experimental and theoretical constraints, we find sizable effects due to the additional heavy neutrinos up to
-
38
%
on the total cross-section at a center-of-mass energy of 3 TeV, and even up to
-
66
%
with suitable cuts. This motivates a detailed sensitivity analysis of the process
e
+
e
-
→
W
+
W
-
H
as it could provide a new, very competitive experimental probe of low-scale neutrino mass models.
Abstract We present the first study of the production of a Standard Model Higgs boson at a lepton collider in association with a pair of W bosons, $$e^+_{} e^-_{} \rightarrow W^+_{} W^-_{} H$$ ...e+e-→W+W-H , in the inverse seesaw model. Taking into account all relevant experimental and theoretical constraints, we find sizable effects due to the additional heavy neutrinos up to $$-38\%$$ -38% on the total cross-section at a center-of-mass energy of 3 TeV, and even up to $$-66\%$$ -66% with suitable cuts. This motivates a detailed sensitivity analysis of the process $$e^+_{} e^-_{} \rightarrow W^+_{} W^-_{} H$$ e+e-→W+W-H as it could provide a new, very competitive experimental probe of low-scale neutrino mass models.
A
bstract
We compute the full next-to-leading order supersymmetric (SUSY) electroweak (EW) and SUSY-QCD corrections to the decays of CP-odd NMSSM Higgs bosons into stop pairs. In our numerical ...analysis we also present the decay of the heavier stop into the lighter stop and an NMSSM CP-odd Higgs boson. Both the EW and the SUSY-QCD corrections are found to be significant and have to be taken into account for a proper prediction of the decay widths.
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