20. 7a. Export citation and abstract BibTeX RIS 1. From numerical results, we find that the decay width of process H b + J / + b at leading order (LO) mainly comes from the contribution of the Fock state S 3 1 (8), and the NLO QCD . aa r X i v : . We calculate the leading logarithmic QCD corrections to the decay B-s --> gamma gamma in the two Higgs doublet model with tree level flavor changing currents (modeI III) including O-7 type long distance effects. . This value, albeit with limited precision, agrees with the standard model prediction. . In the framework of the Little Higgs Model (LHM), we calculate the decay width (Z1 e+e) with corrections of QED and QCD. of this, perturbative corrections to the H bb decay are most interesting for the inclusive rate, due to its contribution to the total decay width and the branching ratios of other decays. We analyze this with recent data from LEP and compute the contribution of the model. The result is presented in the same benchmark model but with no assumption on the total decay width made. The sum of the EW corrections ranges from -4% to 0% for a Higgs mass between 100 GeV and 150 GeV, while the complete correction at two-loop order amounts to less than pm 1.5% in this regime. If the partial width for a Higgs boson to decay via a virtual massive particle can be measured, this gives a measurement of that massive particle's width. Phys . For f = 4 TeV and c = 0.3, the NLO QCD corrected decay width reaches 75.099 keV and the NLO QCD relative correction is about 11.0%. You have to use the Standard model gauge invariant lagrangian of Yukawa interaction of leptons with Higgs doublet, L Yuk = l y L l L H l R, where in the unitary gauge. Alternative one can disentangle deviations in production and decay with explicit modeling of Higgs width . y L m l v. Such term (and coupling constant y l) is required theoretically for introducing gauge invariant leptons mass . The Higgs boson discovery was announced by the ATLAS and CMS collaborations on 4 th July 2012. Decay Widths and Scattering Cross Sections We are now ready to calculate the rates of some simple scattering and decay processes. calculations. Naoyuki Haba 1, Kunio Kaneta 1, 3, Yukihiro Mimura 2, and Ryo The main focus lies on the electroweak (EW) contributions. In this ratio the terms due to the loop integration cancel out. The total width is dominated by Higgs decays to b quark pairs. To test SM an accuracy of about 0.1 MeV (2.5 %) or better is required. 0.2% would decay to two photons () 0.15% would decay to a photon and a Z particle There are three classes of decays in this plot: First, there are decays through direct interactions to a particle and its antiparticle; see Figure 2. To this end we compute four-loop QCD corrections in the large top quark mass expansion to the Higgs boson--photon form factor, which . D. 90, 052004 (2014) (EW) calculation!! Enhancement of Higgs to diphoton decay width. The search for a Higgs boson in the decay products . For the calculation of the case where the Higgs couples to the internal charm quark, i.e., equal masses as- . We perform the numerical calculation by taking the LHM input parameters f = 3, 4 TeV and 0.1 < c < 0.6, and discuss the numerical results of the decay width up to the QCD NLO within the recent experimentally constrained LHM parameter space region. The present paper describes a signicant extension in functionality in SOFTSUSY: to calculate and output the various partial widths for the decays of sparticles and Higgs bosons in the MSSM and in the NMSSM. that the studied particle is a single SM-like Higgs boson state, i.e. Chicken and Egg; Matter and Field; 7. The detectors observed the decay of just a few dozen Higgs bosons into photons, Ws and Zs, which revealed a bump in the data at 125 billion electronvolts (GeV), about 125 times the mass of the proton. The Large Electron-Positron collider (LEP), which operated at CERN from 1989 to 2000, was the first accelerator to have significant reach into the potential mass range of the Higgs boson.
The accelerator, the experiments and the Higgs. A detailed five-dimensional calculation of the Higgs-boson decay into two photons is performed in both the minimal and the custodially protected Randall-Sundrum (RS) model, where the Standard Model (SM) fields propagate in the bulk and the scalar sector lives on or near the IR brane. We determine the width for radiative decay of heavy Higgs bosons HW+W- for hard photons as a function of the Higgs-boson mass and the photon-energy cutoff, and correct the result of a previous calculation. Interference e ects and sensitivity to the Higgs the input to the combined measurement includes the latest results from the decay modes that initially led to the higgs boson discovery: h zz ++ decays 28 with two z bosons that. Jul 4th 2022 (Updated Jul 5th 2022) | Geneva. Please check Proposal on how to provide reference "Higgs" cross sections for BSM applications; Full mass scan should be provided for major Higgs production processes: BibTeX @MISC{Karlsruhe94perturbativeqcd, author = {Universitt Karlsruhe}, title = {Perturbative QCD Corrections to the Z Boson Width and the Higgs Decay Rate 1}, year = {1994}} production with a bottom quark pair from the Higgs boson decay within the nonrelativistic QCD framework. (N.Y.); (United States) W and Z boson pairs are the signals of the production of many types of new, heavy particles, e.g., heavy Higgs bosons, new Z' bosons, heavy quark and lepton pairs, and heavy gaugino pairs. Numerical calculations for the decay widths and the branching ratios are performed by employing the following values: r - . Phys. ). More concretely, we focus on Higgs production through gluon fusion and Higgs decay into two photons induced by loop diagrams. Particles Are Quanta. Future precision measurements of Higgs boson decays will determine the branching fraction for the decay into two photons with a precision at the one percent level. Waves (The Quick Calculation) 5. We present an analytical calculation of the next-to-next-to-leading order corrections to the partial decay width Hgg for a Higgs boson in the intermediate mass range. Another noticeable thing about our results is di erent decay width patterns for M A= 250 GeV and higher masses. We present predictions for ZH and WH production including spin correlations and off-shell effects by calculating the full processes pp . Abstract. Many phenomenological studies have been made of the h ! [ h e p - ph ] J a n NLO Electroweak Corrections to Higgs Decay to TwoPhotons. The Standard Model Higgs boson decay branching ratios and total width are shown in the figure above . The total width is dominated by Higgs decays to b quark pairs. The WW signal identica-tion with leptonic W decay is challenging . The decay width of Higgs boson into massless bottom quarks is known up to the next-to-next-to-next-to-next-to-leading order in QCD [3-5]. e ects in the H!4'decay width. . 6a. The pattern for decay width at 250 GeV can be explained by two factors . A straightforward calculation leads us to the following decay width: r(v + 2-O + Hl+t-) = aM;MiAf(ai + bi) . You can see that the decay modes change in prominance depending on the mass of the Higgs, M H. Effectively, this diagram expresses how likely the Higgs is to decay into a certain particle, or group of particles, depending on the mass of the Higgs. The leading-order (LO) (one-loop) contributions to As have been known for a long time [11,12]. Prophecy4f and our calculation(Hto4l ) for the Higgs decay width (in KeV), for dierent values of the Higgs mass and nal states.The numbers in parenthesis are the statistical uncertainty on the last digit due to MC integration. We consider the Higgsstrahlung process in hadronic collisions and present the computation of next-to-next-to-leading order predictions matched to parton showers for both production and H b b $$ b\\overline{b} $$ decay employing the MiNNLOPS method. Amplitudes FeynmanModel rulesfile Decay Widths @1-loop HDECAY QCD, off-shell, loop-induced 2HDECAY Full result We have performed a one-loop calculation of the width of the rare decay H -> Z Z \gamma in the standard model for Higgs boson masses 190 GeV \leq m_H \leq 250. The Higgs is treated in the narrow-resonance approximation, that is, we take the invariant mass dependence of the Higgs products to have the-form da 1 din2 Y' +( In - lnJf)2 (2) where I' is the greater of the Higgs decay width and the experimental resolution, here taken to be 20 GeV. The leading diagrams for these processes are shown in Figure 1. Original language: English (US) Pages (from-to) 2157-2159: Number of pages: 3: Journal: Physical Review D:
I show that the W and Z bosons which result from the decay of these heavy particles are . Decays of the Higgs boson are understood very well for all practical (LHC) purposes. Ratio of observed rate to predicted standard model event rate for different combinations of Higgs boson production and decay processes The horizontal bar on each point denotes the 68% confidence . We investigate also the possibility that the electroweak vacuum could be destabilized by unwanted wrong . We find that there is a considerable enhancement in the decay width and neutral Higgs effects are detectable for large values of . SM Higgs width calculation accuracy will be improved with a better mass measurement LHC accuracy of M H is now about ~150 MeV, ILC can reach accuracy of ~(20-30) MeV 2 EPHOU-12-005 [-1mm] OU-HET 754/2012. Abstract We calculate decays of a standard model Higgs boson via a virtual massive particle and discuss how this depends on the massive particle total width. From numerical results, we find that the decay width of process H b J= b at leading order (LO) mainly comes from the contribution of the Fock state 3S8 1, and the NLO QCD corrections We calculate decays of a standard model Higgs boson via a virtual massive particle and discuss how this depends on the massive particle total width. In the Standard Model of particle physics, the Higgs mechanism is essential to explain the generation mechanism of the property "mass" for gauge bosons.Without the Higgs mechanism, all bosons (one of the two classes of particles, the other being fermions) would be considered massless, but measurements show that the W +, W , and Z 0 bosons actually have relatively large masses of around 80 . 6.2 D= 6 contributions to Higgs decay into four charged leptons .107 . in non-perturbative Higgs model . If the partial width for a Higgs boson to decay via a virtual massive particle can be measured, this gives a measurement of that massive particle {close_quote}s width. The value of . The former is expressed in terms of cross section, , which is a measure of the probability of a specic scattering process under some given set of initial and nal conditions, such as momenta and spin . ); where the refers to partial decay width. It is shown that this decay provides an additional possibility for charged Higgs searches. How Bosons and Fermions Differ; 8. Right hand plot shows the total cross sections for Ecm = 7, 8 and 14 TeV. Here is a paper with Feynman diagrams for Higgs decays. Mass scan: s = 7 and 8 TeV (for updates) and 13 and 14 TeV . The leading term confirms the results present in the literature. For H both inclusive (solid line) and VBF (dashed line) mode are plotted. the h decay rate, and the total Higgs width. The new result by the CMS collaboration sets a milestone in testing the properties of the Higgs boson. The value of the Higgs boson lifetime is inferred to be (2.1 +2.3-0.9) x 10 -22 seconds where the two extra numbers give the uncertainty of the measurement. In this paper, we calculated the decay width and decay branch ratio of Higgs decay to h c plus a photon in the theoretical framework of NRQCD. Our results show that the two-loop QCD correction always reduces the LO decay width and the top . Figure 2: Standard Model Higgs boson decay branching ratios and total width. The Higgs invisible decay width may soon become a powerful tool to probe extensions of the Standard Model with dark matter candidates at the Large Hadron Collider. A detailed five-dimensional calculation of the Higgs-boson decay into two photons is performed in both the minimal and the custodially protected Randall-Sundrum (RS) model, where the Standard Model (SM) fields propagate in the bulk and the scalar sector lives on or near the IR brane. 2 a comparison between.
in intermediate-mass .
NNLO calculation of Higgs production test of theory framework For LO, m = 2.6 0.4, NLO , m = 1.9 0.3 .
= (H ! Abstract Motivated by recent results from Higgs searches at the Large Hadron Collider, we consider possibilities to enhance the diphoton decay width of the Higgs boson over the Standard Model expectation, without modifying either its production rate or the partial widths in the WW and ZZ channels. Original language: English (US) Pages (from-to) 2157-2159: Number of pages: 3: Journal: Physical Review D: Waves (Quantum) 6. "I was actually shaking," said Mitesh Patel, a particle physicist at Imperial College, London, as he describes the moment he saw the results. The theoretical calculations of the Higgs boson production cross sections and decay branching ratios have been compiled in Refs. ) (H ! We reproduce also the plot for Higgs branching ratios for di erent decay channels as a function of its mass. Prophecy4f and
HDECAY HDECAY is a self-contained and fast program for calculating the decay widths and branching ratios of the SM Higgs boson, and the Higgs bosons of the MSSM according to the current theoretical knowledge. Our e ect is also complementary to the o -shell method [12{14], since it is independent of new physics e ects that may distort the measurements in the far o -shell region. a CP-even scalar particle with the tensor structure of the SM interactions. We consider the change of the Higgs width decay into a fermion pair with respect to the standard model, due to the four-fermion contact interaction coming from the existence of gravitational torsion within the context of extra dimension scenarios. Decays of the Higgs boson are understood very well for all practical (LHC) purposes. aim: calculate all 2HDM Higgs boson decays @1-loop (electroweak) use perturbation theoryto solve the scattering matrix S at 1-loop level 2HDM electroweak Lagrangian" Processes, e.g. In this work, we calculate the next-to-leading order (NLO) electroweak corrections to the 125 GeV Higgs decay width into two dark matter particles. It enters the h decay width as h M3 h 64 jAsj2; 2 where Mh is the mass of the Higgs boson. The role of possible background processes is discussed. Evaluate the Feynman integrals in the above calculations (numerically) with Mathematica/Maple for m h = 125 GeV and add up all contributions to get the total decay width of the Higgs boson. The leading term confirms the results present in the . Higgs-decay into two photons important detection channel in this mass range at Large Hadron Collider (LHC) due to clear signature, though . 2.5% would decay to charm (c) quark/antiquark pairs 2.5% would decay to Z particles (though see below!) We find that the deviations of the decay width of reaction Z1 e+e from its SM value are relatively large in the parameter space preferred by the electroweak precision data . W signal [W 16-20] and that of the closely related h ! 48~ sin6 Bw co@ Bw . This result shows how the value FV = 0, which would correspond to a fermiofobic Higgs boson, is disfavoured at the 4 level. Higgs boson mass is only parameter unconstrained by SM But crucial in SM prediction of Higgs production and decay rates Measurement based on H!ZZ* and H! nal states, for which invariant mass can be reconstructed with high precision Wouter Verkerke, NIKHEF 6 Eur . Journal Article Willenbrock, S - Ann. The Basic Idea. 4a. In particular, an E ective Field Theory (EFT) framework has been adopted for a model independent parametrization .
calculation di ers from the one implemented in Prophecy4f , where multi- . The number of Higgs-related events is given by the product of the Higgs boson production cross section in a particular channel and the Higgs boson decay rate to a particular nal state. A remarkable eort has been made for a precise calculation of Hbb and now QCD corrections are known to O(4 s) [1-9]. Fields. Our results show that the two-loop QCD correction always reduces the LO decay width and the top-induced QCD correction is the dominant contribution at the QCD NLO.
The motivation for the program according to the authors is: "The search of the Higgs boson is one of the V. 2. 4. J. We found that the branch ratio is about 0.187 10 8 , and there will not be enough events to produce with integrated luminosity 3000 fb 1 at the 14 TeV LHC. They can be decomposed into W-boson contributions, AW, as well as fermionic We present an analytical calculation of the next-to-next-to-leading order corrections to the partial decay width H g g for a Higgs boson in the intermediate mass range. The number of Higgs-related events is given by the product of the Higgs boson production cross section in a particular channel and the Higgs boson decay rate to a particular nal state. 1. Feynman diagrams are the recipe for setting up the integrals necessary to be calculated for finding widths and crossections in particle physics. 0.6 0.8 1 1.2 1.4 1 . BSM Higgs-boson production cross section calculation and decay width . We show that there are regions of parameter space in multi-scalar doublet models where, in the first few hundred inverse femtobarns of data, the new charged and neutral scalars are not directly observable at the LHC and yet the Higgs decay rate to bb is changed significantly from its standard model value.
In this work, we investigate the parameter space of the Georgi-Machacek (GM) model, where we consider many theoretical and experimental constraints such as the perturbativity, vacuum stability, unitarity, electroweak precision tests, the Higgs di-photon decay and the Higgs total decay width. For the ggF process, the cross section is computed at up to NNLO in QCD corrections [33-38] and NLO in electroweak (EW) corrections [39-41]. In Fig. C 74 (2014) 3076 . particles. The calculation of the rare t-quark decay t!b bbW + within the Standard Model as well as the charged Higgs contribution to this decay is presented. They are one-loop leading processes and the contribution of Kaluza-Klein particles is considered to be . The natural width of the Higgs boson is expected to be very small (<< resolution) . The branching ratio of the Higgs boson decaying toZZ cancels out in the FV ratio. We discuss how one would go about measuring these partial widths of a Higgs boson . We recompute the invisible Higgs decay width arising from Higgs-graviscalar mixing in the Arkani-Hamed, Dimopoulos, Dvali model, comparing the original derivation in the nondiagonal mass basis to that in a diagonal mass basis. in the triangle loop, contribute to the decay width of. weak coupling is shared by two neutral Higgs states, as would be the case in supersymmetry [15], or if the Higgs has invisible decay modes. The easiest way to evaluate the rate for such internal conversions is to calculate the ratio of the Higgs decay rate to a photon and a virtual photon and decay to a pair of real photons. Though LEP did not find the Higgs boson, it made significant headway in the search, determining that the mass should be larger than 114 GeV. In this work, we investigate the next-to-leading order (NLO) QCD correction to J / associated production with a bottom quark pair from the Higgs boson decay within the nonrelativistic QCD framework. For h0!ff you have to include only the following fermions: b b, + and c c (why? the h decay rate, and the total Higgs width. Measurement of width using interferometry qq ZZ and gg ZZ (continuum) . In order to identify the Higgs sector using future precision data, we calculate the partial decay widths of the discovered Higgs boson with the mass o background in Higgs decays (resulting in Higgs mass shift and cross section reduction). Top-quark-induced corrections Higgs Decay to Photons at Two Loops Calculation of leading term proportional GFm2 t Bottom-quark massless . Abstract: We calculate loop-induced Higgs production and decay processes which are relevant for the LHC in various six-dimensional Universal Extra Dimension models. Higgs - boson production. We apply an asymptotic expansion for M H 2 M t and compute three terms in the expansion. H = ( 0 h + v), L ( L l l L) and. The framework - the total width Note that total H width scales all observed cross-sections Total decay width and branching fraction of the Higgs boson (a) (5P.) How Particles and Fields Interact (an introduction) How the Higgs Field Works (with math) 1. Abstract We present numerical calculations of the partial width of the charged Higgs boson decay into a top quark, H $$ \overline{t} $$ t + b + X, and the partial width of the top quark decay into a light charged Higgs boson t H+ + b + X at next-to-next-to-leading order (NNLO) in QCD, based on a factorization formula of the jet mass. Enter the email address you signed up with and we'll email you a reset link. The results obtained are identical (and differ by a factor of 2 from the original calculation) but the diagonal-basis derivation is pedagogically useful for clarifying . As the rst part of this paper we get to analyze Standard Model (SM) Higgs boson main decay channels, at tree level for massive nal state particles and at one loop for gluons. Evidence for a new particle with the mass of about 125 GeV and the properties of the Standard Model Higgs boson was present in the three decay modes H ZZ* , H , and H WW* in both experiments. The calculation is carried out using integration-by-parts identities for the reduction to master integrals of the scalar integrals, in terms of which we express the amplitude. We apply an asymptotic. PACS: 12.38.-t, 14.54Ha Precise prediction of decay width ( H ! ) Global measurement of Higgs width 12/5/2014 21 . Emphasis has been placed on speed of execution, preferring to perform as much of the calculation analytically as is practicable. We determine the width for radiative decay of heavy Higgs bosons HW+W- for hard photons as a function of the Higgs-boson mass and the photon-energy cutoff, and correct the result of a previous calculation. [30-32] and are summarised in Table1. The Basic Idea (1st version) 2. To fully exploit such measurements, equally precise theoretical predictions need to be available. For a light Higgs with a mass less than 140 GeV, this can cause a large change in the . Why the Higgs Field is Non-Zero on . formation on the Higgs total decay width from an on-shell Higgs boson cross section measurement. This is expected since the higher the particle mass the more decay channels open. . We apply an asymptotic expansion for MH 2Mt and compute three terms in the expansion. The calculation of the two-loop corrections to the partial width of an intermediate-mass Higgs boson decaying into a pair of photons is reviewed. Z channel [Z 21-25]. The Higgs boson width, predicted to be approximately 4 MeV in the SM, is assumed to be small such that the narrow-width approximation is valid and that production and decay can be decomposed. The rst observation one can do is that the decay width increases with M A. We present the analytic calculation of the two-loop QCD corrections to the decay width of a Higgs boson into a photon and a Z boson. Stefano Actis Institut fur Theoretische Physik E, RWTH Aachen University,D-52056 Aachen - GermanyThe recent calculation of the next-to-leading order electroweak corrections to the decayof the Standard Model Higgs boson to two photons in the framework of the complex-mass scheme is briey .
Higgs decay candidates to various final states 12/5/2014 . To get an idea of the complexity of the calculations just for the Higgs to three particles, not four, : CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): We present an analytical calculation of the next-to-next-to-leading order corrections to the partial decay width H gg for a Higgs boson in the intermediate mass range. The differ- . The two most sensitive decay channels at the LHC are H ZZ 4 and H , the so called golden channels of the Higgs boson decays. "I . Figure 3: Standard Model Higgs boson production cross section times branching ratio at Ecm= 8 TeV.