Publications (279)722.5 Total impact

Article: Interference contributions to gluon initiated heavy Higgs production in the TwoHiggsDoublet Model
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ABSTRACT: We discuss the production of a heavy neutral Higgs boson of a CPconserving TwoHiggsDoublet Model in gluon fusion and its decay into a fourfermion final state, $gg (\rightarrow VV) \rightarrow e^+e^\mu^+\mu^/e^+e^\nu_l\bar\nu_l$. We investigate the interference contributions to invariant mass distributions of the fourfermion final state and other relevant kinematical observables. The relative importance of the different contributions is quantified for the process in the onshell approximation, $gg\rightarrow ZZ$. We show that interferences of the heavy Higgs with the light Higgs boson and background contributions are essential for a correct description of the differential cross section. Even though they contribute below $\mathcal{O}(10\%)$ to those heavy Higgs signal cross sections, to which the experiments at the Large Hadron Collider were sensitive in its first run, we find that they are sizeable in certain regions of the parameter space that are relevant for future heavy Higgs boson searches. In fact, the interference contributions can significantly enhance the experimental sensitivity to the heavy Higgs boson.  [Show abstract] [Hide abstract]
ABSTRACT: Different mechanisms operate in various regions of the MSSM parameter space to bring the relic density of the lightest neutralino, neutralino_1, assumed here to be the LSP and thus the Dark Matter (DM) particle, into the range allowed by astrophysics and cosmology. These mechanisms include coannihilation with some nearlydegenerate nexttolightest supersymmetric particle (NLSP) such as the lighter stau (stau_1), stop (stop_1) or chargino (chargino_1), resonant annihilation via directchannel heavy Higgs bosons H/A, the light Higgs boson h or the Z boson, and enhanced annihilation via a larger Higgsino component of the LSP in the focuspoint region. These mechanisms typically select lowerdimensional subspaces in MSSM scenarios such as the CMSSM, NUHM1, NUHM2 and pMSSM10. We analyze how future LHC and direct DM searches can complement each other in the exploration of the different DM mechanisms within these scenarios. We find that the stau_1 coannihilation regions of the CMSSM, NUHM1, NUHM2 can largely be explored at the LHC via searches for missing E_T events and longlived charged particles, whereas their H/A funnel, focuspoint and chargino_1 coannihilation regions can largely be explored by the LZ and Darwin DM direct detection experiments. We find that the dominant DM mechanism in our pMSSM10 analysis is chargino_1 coannihilation: {parts of its parameter space can be explored by the LHC, and a larger portion by future direct DM searches.  [Show abstract] [Hide abstract]
ABSTRACT: LHC searches for nonstandard Higgs bosons decaying into tau lepton pairs constitute a sensitive experimental probe for physics beyond the Standard Model (BSM), such as Supersymmetry (SUSY). Recently, the limits obtained from these searches have been presented by the CMS collaboration in a nearly modelindependent fashion  as a narrow resonance model  based on the full 8 TeV dataset. In addition to publishing a 95% C.L. exclusion limit, the full likelihood information for the narrow resonance model has been released. This provides valuable information that can be incorporated into global BSM fits. We present a simple algorithm that maps an arbitrary model with multiple neutral Higgs bosons onto the narrow resonance model and derives the corresponding value for the exclusion likelihood from the CMS search. This procedure has been implemented into the public computer code HiggsBounds (version 4.2.0 and higher). We validate our implementation by crosschecking against the official CMS exclusion contours in three Higgs benchmark scenarios in the Minimal Supersymmetric Standard Model (MSSM), and find very good agreement. Going beyond validation, we discuss the combined constraints of the tau tau search and the rate measurements of the SMlike Higgs at 125 GeV in a recently proposed MSSM benchmark scenario, where the lightest Higgs boson obtains SMlike couplings independently of the decoupling of the heavier Higgs states. Technical details for how to access the likelihood information within HiggsBounds are given in the appendix. The program is available at http://higgsbounds.hepforge.org.  [Show abstract] [Hide abstract]
ABSTRACT: Electroweak precision observables, being highly sensitive to loop contributions of new physics, provide a powerful tool to test the theory and to discriminate between different models of the underlying physics. In that context, the $W$ boson mass, $M_W$, plays a crucial role. The accuracy of the $M_W$ measurement has been significantly improved over the last years, and further improvement of the experimental accuracy is expected from future LHC measurements. In order to fully exploit the precise experimental determination, an accurate theoretical prediction for $M_W$ in the Standard Model (SM) and extensions of it is of central importance. We present the currently most accurate prediction for the $W$ boson mass in the NexttoMinimal Supersymmetric extension of the Standard Model (NMSSM), including the full oneloop result and all available higherorder corrections of SM and SUSY type. The evaluation of $M_W$ is performed in a flexible framework, which facilitates the extension to other models beyond the SM. We show numerical results for the $W$ boson mass in the NMSSM, focussing on phenomenologically interesting scenarios, in which the Higgs signal can be interpreted as the lightest or second lightest CPeven Higgs boson of the NMSSM. We find that, for both Higgs signal interpretations, the NMSSM $M_W$ prediction is well compatible with the measurement. We study the SUSY contributions to $M_W$ in detail and investigate in particular the genuine NMSSM effects from the Higgs and neutralino sectors. 
Article: The pMSSM10 after LHC run 1
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ABSTRACT: We present a frequentist analysis of the parameter space of the pMSSM10, in which the following ten soft SUSYbreaking parameters are specified independently at the mean scalar top mass scale \(M_\mathrm{SUSY}\equiv \sqrt{m_{\tilde{t}_{1}} m_{\tilde{t}_{2}}}\): the gaugino masses \(M_{1,2,3}\), the firstand secondgeneration squark masses \(m_{\tilde{q}_1}= m_{\tilde{q}_2}\), the thirdgeneration squark mass \(m_{\tilde{q}_3}\), a common slepton mass \(m_{\tilde{\ell }}\) and a common trilinear mixing parameter A, as well as the Higgs mixing parameter \(\mu \), the pseudoscalar Higgs mass \(M_A\) and \(\tan \beta \), the ratio of the two Higgs vacuum expectation values. We use the MultiNest sampling algorithm with \(\sim \)1.2 \(\times 10^9\) points to sample the pMSSM10 parameter space. A dedicated study shows that the sensitivities to strongly interacting sparticle masses of ATLAS and CMS searches for jets, leptons \(+\) signals depend only weakly on many of the other pMSSM10 parameters. With the aid of the Atom and Scorpion codes, we also implement the LHC searches for electroweakly interacting sparticles and light stops, so as to confront the pMSSM10 parameter space with all relevant SUSY searches. In addition, our analysis includes Higgs mass and rate measurements using the HiggsSignals code, SUSY Higgs exclusion bounds, the measurements of \(\mathrm{BR}(B_s \rightarrow \mu ^+\mu ^)\) by LHCb and CMS, other Bphysics observables, electroweak precision observables, the cold dark matter density and the XENON100 and LUX searches for spinindependent dark matter scattering, assuming that the cold dark matter is mainly provided by the lightest neutralino \(\tilde{\chi }^0_{1}\). We show that the pMSSM10 is able to provide a supersymmetric interpretation of \((g2)_\mu \), unlike the CMSSM, NUHM1 and NUHM2. As a result, we find (omitting Higgs rates) that the minimum \(\chi ^2 = 20.5\) with 18 degrees of freedom (d.o.f.) in the pMSSM10, corresponding to a \(\chi ^2\) probability of 30.8 %, to be compared with \(\chi ^2/\mathrm{d.o.f.} = 32.8/24 \ (31.1/23) \ (30.3/22)\) in the CMSSM (NUHM1) (NUHM2). We display the onedimensional likelihood functions for sparticle masses, and we show that they may be significantly lighter in the pMSSM10 than in the other models, e.g., the gluino may be as light as \(\sim \)1250 \(\,\, \mathrm {GeV}\) at the 68 % CL, and squarks, stops, electroweak gauginos and sleptons may be much lighter than in the CMSSM, NUHM1 and NUHM2. We discuss the discovery potential of future LHC runs, \(e^+e^\) colliders and direct detection experiments. 
Article: Physics at the e+ e Linear Collider
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ABSTRACT: A comprehensive review of physics at an e+e Linear Collider in the energy range of sqrt{s}=92 GeV3 TeV is presented in view of recent and expected LHC results, experiments from low energy as well as astroparticle physics.The report focuses in particular on Higgs boson, Top quark and electroweak precision physics, but also discusses several models of beyond the Standard Model physics such as Supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analyzed as well.  [Show abstract] [Hide abstract]
ABSTRACT: The importance of offshell contributions is discussed for $H\to VV^{(*)}$ with $V\in\{Z,W\}$ for large invariant masses $m_{VV}$ involving a standard model (SM)like Higgs boson with $m_H=125$GeV at a linear collider (LC). Both dominant production processes $e^+e^\to ZH\to ZVV^{(*)}$ and $e^+e^\to\nu\bar\nu H\to\nu\bar\nu VV^{(*)}$ are taken into account, and the signal processes are compared with background yielding the same final state. The relative size of the offshell contributions is strongly dependent on the centreofmass energy. These contributions can have an important impact on the determination of cross sections and branching ratios. However, the combination of on and offshell contributions can also be utilised to lift degeneracies allowing to test higherdimensional operators, unitarity and light and heavy Higgs interferences in extended Higgs sectors. The latter is demonstrated in the context of a 2HiggsDoublet model. Where relevant, the impact of these aspects for physics at the Large Hadron Collider (LHC) is discussed. The importance of a precise measurement of the Higgs mass for onshell contributions in $H\to VV^{(*)}$ is emphasized. A particular focus is put on methods for extracting the Higgs width at a LC. Offshell contributions are shown to have a negligible impact on the width determination at low $\sqrt{s}$ when applying the $Z$ recoil method to extract branching ratios in combination with an appropriate determination of a partial width. On the other hand, offshell contributions can be exploited to constrain the Higgs width in a similar fashion as in recent analyses at the LHC. It is demonstrated that this approach, besides relying heavily on theoretical assumptions, is affected by the negative interference of Higgs and background contributions that may limit the sensitivity that is achievable with the highest foreseeable statistics at the LHC and a LC. 
Article: Higgsboson Physics at the LHC
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ABSTRACT: The discovery of a Higgs boson or the exclusion of such a particle in a wide mass range from 100 to 1000GeV was a major design goal of the LHC and the experiments ATLAS and CMS. The discovery of a Higgslike particle at a mass around 125GeV marked the beginning of a new era in particle physics. A snapshot of early results at the time of discovery and detailed investigations of the properties of the new particle with the full LHC data set taken in the years 2010–2012 at centreofmass energies of 7 and 8TeV as well as remaining open questions are the main focus of this chapter.  [Show abstract] [Hide abstract]
ABSTRACT: A generalisation of the narrowwidth approximation (NWA) is formulated which allows for a consistent treatment of interference effects between nearly massdegenerate particles in the factorisation of a more complicated process into production and decay parts. It is demonstrated that interference effects of this kind arising in BSM models can be very large, leading to drastic modifications of predictions based on the standard NWA. The application of the generalised NWA is demonstrated both at tree level and at oneloop order for an example process where the neutral Higgs bosons h and H of the MSSM are produced in the decay of a heavy neutralino and subsequently decay into a fermion pair. The generalised NWA, based on onshell matrix elements or their approximations leading to simple weight factors, is shown to produce UV and IRfinite results which are numerically close to the result of the full process at tree level and at oneloop order, where an agreement of better than \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{69pt} \begin{document}$$1\,\%$$\end{document}1% is found for the considered process. The most accurate prediction for this process based on the generalised NWA, taking into account also corrections that are formally of higher orders, is briefly discussed. 
Article: The NUHM2 after LHC Run 1
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ABSTRACT: We make a frequentist analysis of the parameter space of the NUHM2, in which the soft supersymmetry (SUSY)breaking contributions to the masses of the two Higgs multiplets, $m^2_{H_{u,d}}$, vary independently from the universal soft SUSYbreaking contributions $m^2_0$ to the masses of squarks and sleptons. Our analysis uses the MultiNest sampling algorithm with over $4 \times 10^8$ points to sample the NUHM2 parameter space. It includes the ATLAS and CMS Higgs mass measurements as well as their searches for supersymmetric jets + MET signals using the full LHC Run~1 data, the measurements of $B_s \to \mu^+ \mu^$ by LHCb and CMS together with other Bphysics observables, electroweak precision observables and the XENON100 and LUX searches for spinindependent dark matter scattering. We find that the preferred regions of the NUHM2 parameter space have negative SUSYbreaking scalar masses squared for squarks and sleptons, $m_0^2 < 0$, as well as $m^2_{H_u} < m^2_{H_d} < 0$. The tension present in the CMSSM and NUHM1 between the supersymmetric interpretation of $g_\mu  2$ and the absence to date of SUSY at the LHC is not significantly alleviated in the NUHM2. We find that the minimum $\chi^2 = 32.5$ with 21 degrees of freedom (dof) in the NUHM2, to be compared with $\chi^2/{\rm dof} = 35.0/23$ in the CMSSM, and $\chi^2/{\rm dof} = 32.7/22$ in the NUHM1. We find that the onedimensional likelihood functions for sparticle masses and other observables are similar to those found previously in the CMSSM and NUHM1.  [Show abstract] [Hide abstract]
ABSTRACT: In 2012, the discovery of a particle compatible with a Higgs boson of a mass of roughly 125 GeV was announced. This great success is now being followed by the identification of the nature of this particle and the particle's properties are being measured. One of these properties is the Higgs boson mass which is already known very precisely with an experimental uncertainty of below 1 GeV. In some extensions of the Standard Model, like in supersymmetric extensions, the Higgs boson mass can be predicted and hence, the measured mass constrains the parameters of the model. For a full exploitation of this constraint, a precise theoretical prediction is needed. The presented combination of the results obtained by the Feynman diagrammatic approach and the renormalization group equation approach improves the known Higgs mass prediction for larger mass scales of the superpartner particles.  [Show abstract] [Hide abstract]
ABSTRACT: For the interpretation of the signal discovered in the Higgs searches at the LHC it will be crucial in particular to discriminate between the minimal Higgs sector realized in the standard model (SM) and its most commonly studied extension, the minimal supersymmetric standard model (MSSM). The measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role in this context. In the MSSM the mass of the light CPeven Higgs boson, Mh, can directly be predicted from the other parameters of the model. The accuracy of this prediction should at least match the one of the experimental result. The relatively high mass value of about 126 GeV has led to many investigations where the scalar top quarks are in the multiTeV range. We improve the prediction for Mh in the MSSM by combining the existing fixedorder result, comprising the full oneloop and leading and subleading twoloop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a highprecision prediction for the mass of the light CPeven Higgs boson in the MSSM is possible all the way up to the multiTeV region of the relevant supersymmetric particles. The results are included in the code FeynHiggs.  [Show abstract] [Hide abstract]
ABSTRACT: The signal discovered in the Higgs searches at the LHC can be interpreted as the Higgs boson of the Standard Model as well as the light CPeven Higgs boson of the Minimal Supersymmetric Standard Model (MSSM). In this context the measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role. This precision can be improved substantially below the level of about 50 MeV at the future International Linear Collider (ILC). Within the MSSM the mass of the light CPeven Higgs boson, M_h, can directly be predicted from the other parameters of the model. The accuracy of this prediction should match the one of the experimental measurements. The relatively high experimentally observed value of the mass of about 125.6 GeV has led to many investigations where the supersymmetric (SUSY) partners of the top quark have masses in the multiTeV range. We review the recent improvements for the prediction for M_h in the MSSM for large scalar top masses. They were obtained by combining the existing fixedorder result, comprising the full oneloop and leading and subleading twoloop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a highprecision prediction for the mass of the light CPeven Higgs boson in the MSSM is possible all the way up to the multiTeV region of the relevant supersymmetric particles. However, substantial further improvements will be needed to reach the ILC precision. The newly obtained corrections to M_h are included into the code FeynHiggs. 
Article: Probing the Standard Model with Higgs signal rates from the Tevatron, the LHC and a future ILC
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ABSTRACT: We explore the room for possible deviations from the Standard Model (SM) Higgs boson coupling structure in a systematic study of Higgs coupling scale factor benchmark scenarios using the latest signal rate measurements from the Tevatron and LHC experiments. We employ a profile likelihood method based on a chisquared test performed with HiggsSignals, which takes into account detailed information on signal efficiencies and major correlations of theoretical and experimental uncertainties. All considered scenarios allow for additional nonstandard Higgs boson decay modes, and various assumptions for constraining the total decay width are discussed. No significant deviations from the SM Higgs boson coupling structure are found in any of the investigated benchmark scenarios. We derive upper limits on an additional (undetectable) Higgs decay mode under the assumption that the Higgs couplings to weak gauge bosons do not exceed the SM prediction. We furthermore discuss the capabilities of future facilities for probing deviations from the SM Higgs couplings, comparing the high luminosity upgrade of the LHC with a future International Linear Collider (ILC), where for the latter various energy and luminosity scenarios are considered. At the ILC modelindependent measurements of the coupling structure can be performed, and we provide estimates of the precision that can be achieved. 
Article: The CMSSM and NUHM1 after LHC run 1
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ABSTRACT: We analyze the impact of data from the full Run 1 of the LHC at 7 and 8 TeV on the CMSSM with mu > 0 and < 0 and the NUHM1 with mu > 0, incorporating the constraints imposed by other experiments such as precision electroweak measurements, flavour measurements, the cosmological density of cold dark matter and the direct search for the scattering of dark matter particles in the LUX experiment. We use the following results from the LHC experiments: ATLAS searches for events with MET accompanied by jets with the full 7 and 8 TeV data, the ATLAS and CMS measurements of the mass of the Higgs boson, the CMS searches for heavy neutral Higgs bosons and a combination of the LHCb and CMS measurements of B_s to mu+mu and B_d to mu+mu. Our results are based on samplings of the parameter spaces of the CMSSM for both mu>0 and mu<0 and of the NUHM1 for mu > 0 with 6.8 x 10^6, 6.2 x 10^6 and 1.6 x 10^7 points, respectively, obtained using the MultiNest tool. The impact of the Higgs mass constraint is assessed using FeynHiggs 2.10.0, which provides an improved prediction for the masses of the MSSM Higgs bosons in the region of heavy squark masses. It yields in general larger values of M_h than previous versions of FeynHiggs, reducing the pressure on the CMSSM and NUHM1. We find that the global chi^2 functions for the supersymmetric models vary slowly over most of the parameter spaces allowed by the Higgs mass and the MET searches, with bestfit values that are comparable to the chi^2/dof for the best Standard Model fit. We provide 95% CL lower limits on the masses of various sparticles and assess the prospects for observing them during Run 2 of the LHC.  [Show abstract] [Hide abstract]
ABSTRACT: We discuss the allowed parameter spaces of supersymmetric scenarios in light of improved Higgs mass predictions provided by FeynHiggs 2.10.0. The Higgs mass predictions combine Feynmandiagrammatic results with a resummation of leading and subleading logarithmic corrections from the stop/top sector, which yield a significant improvement in the region of large stop masses. Scans in the pMSSM parameter space show that, for given values of the soft supersymmetrybreaking parameters, the new logarithmic contributions beyond the twoloop order implemented in FeynHiggs tend to give larger values of the light CPeven Higgs mass, M_h, in the region of large stop masses than previous predictions that were based on a fixedorder Feynmandiagrammatic result, though the differences are generally consistent with the previous estimates of theoretical uncertainties. We reanalyze the parameter spaces of the CMSSM, NUHM1 and NUHM2, taking into account also the constraints from CMS and LHCb measurements of B_s to \mu+\mu and ATLAS searches for MET events using 20/fb of LHC data at 8 TeV. Within the CMSSM, the Higgs mass constraint disfavours tan beta lesssim 10, though not in the NUHM1 or NUHM2.  [Show abstract] [Hide abstract]
ABSTRACT: We present the currently most precise W boson mass (M_W) prediction in the Minimal Supersymmetric Standard Model (MSSM) and discuss how it is affected by recent results from the LHC. The evaluation includes the full oneloop result and all known higher order corrections of SM and SUSY type. We show the MSSM prediction in the M_Wm_t plane, taking into account constraints from Higgs and SUSY searches. We point out that even if stops and sbottoms are heavy, relatively large SUSY contributions to M_W are possible if either charginos, neutralinos or sleptons are light. In particular we analyze the effect on the M_W prediction of the Higgs signal at about 125.6 GeV, which within the MSSM can in principle be interpreted as the light or the heavy CPeven Higgs boson. For both interpretations the predicted MSSM region for M_W is in good agreement with the experimental measurement. We furthermore discuss the impact of possible future LHC results in the stop sector on the M_W prediction, considering both the cases of improved limits and of the detection of a scalar top quark.  [Show abstract] [Hide abstract]
ABSTRACT: We describe the new developments in version 4 of the public computer code HiggsBounds. HiggsBounds is a tool to test models with arbitrary Higgs sectors, containing both neutral and charged Higgs bosons, against the published exclusion bounds from Higgs searches at the LEP, Tevatron and LHC experiments. From the model predictions for the Higgs masses, branching ratios, production cross sections and total decay widths  which are specified by the user in the input for the program  the code calculates the predicted signal rates for the search channels considered in the experimental data. The signal rates are compared to the expected and observed cross section limits from the Higgs searches to determine whether a point in the model parameter space is excluded at 95% confidence level. In this document we present a modification of the HiggsBounds main algorithm that extends the exclusion test in order to ensure that it provides useful results in the presence of one or more significant excesses in the data, corresponding to potential Higgs signals. We also describe a new method to test whether the limits from an experimental search performed under certain model assumptions can be applied to a different theoretical model. Further developments discussed here include a framework to take into account theoretical uncertainties on the Higgs mass predictions, and the possibility to obtain the $\chi^2$ likelihood of Higgs exclusion limits from LEP. Extensions to the user subroutines from earlier versions of HiggsBounds are described. The new features are demonstrated by additional example programs.  [Show abstract] [Hide abstract]
ABSTRACT: With the discovery of the Higgs boson, the spectrum of particles in the Standard Model (SM) is complete. It is more important than ever to perform precision measurements and to test for deviations from SM predictions in the electroweak sector. In this report, we investigate two themes in the arena of precision electroweak measurements: the electroweak precision observables (EWPOs) that test the particle content and couplings in the SM and the minimal supersymmetric SM, and the measurements involving multiple gauge bosons in the final state which provide unique probes of the basic tenets of electroweak symmetry breaking. Among the important EWPOs we focus our discussion on M_W and sin^2 theta_eff^l, and on anomalous quartic gauge couplings probed by triboson production and vector boson scattering. We investigate the thresholds of precision that need to be achieved in order to be sensitive to new physics. We study the precision that can be achieved at various facilities on these observables. We discuss the calculational tools needed to predict SM rates and distributions in order to perform these measurements at the required precision. This report summarizes the work of the Energy Frontier Precision Study of Electroweak Interactions working group of the 2013 Community Summer Study (Snowmass). 
Article: ILC Higgs White Paper
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ABSTRACT: The ILC Higgs White Paper is a review of Higgs Boson theory and experiment at the International Linear Collider (ILC). Theory topics include the Standard Model Higgs, the twoHiggs doublet model, alternative approaches to electroweak symmetry breaking, and precision goals for Higgs boson experiments. Experimental topics include the measurement of the Higgs cross section times branching ratio for various Higgs decay modes at ILC center of mass energies of 250, 500, and 1000 GeV, and the extraction of Higgs couplings and the total Higgs width from these measurements. Luminosity scenarios based on the ILC TDR machine design are used throughout. The gammagamma collider option at the ILC is also discussed.
Publication Stats
20k  Citations  
722.50  Total Impact Points  
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Institutions

20102015

Deutsches ElektronenSynchrotron
Hamburg, Hamburg, Germany 
Imperial College London
Londinium, England, United Kingdom 
Universität Siegen
Siegen, North RhineWestphalia, Germany


20012010

Durham University
 • Institute for Particle Physics Phenomenology "IPPP"
 • Department of Physics
Durham, England, United Kingdom


2007

Max Planck Institute for Physics
München, Bavaria, Germany


2006

University of Freiburg
Freiburg, BadenWürttemberg, Germany


19992003

CERN
 • Theoretical Physics Unit (TH)
 • Physics Department (PH)
Genève, Geneva, Switzerland


1998

Karlsruhe Institute of Technology
Carlsruhe, BadenWürttemberg, Germany


1996

Bielefeld University
 Faculty of Physics
Bielefeld, North RhineWestphalia, Germany


1994

University of Wuerzburg
 Department of Theoretical and Astrophysics
Würzburg, Bavaria, Germany
