Discovery Potential of New Boson $W_1^{\\pm}$ in the Minimal Higgsless Model at LHC
Bian, Jian-Guo; Chen, Ming-Shui; Li, Zu-Hao; Liang, Song; Meng, Xiang-Wei; Qi, Yong-Hui; Tang, Zhi-Cheng; Tao, Jun-Quan; Wang, Jian; Wang, Jian; Wang, Xian-You; Wang, Jian-Xiong; Xiao, Hong; Yang, Min; Zang, Jing-Jing; Wang, Zheng; Zhang, Bin; Zhang, Zhen; Zhang, Zhen-Xia; 10.1016/j.nuclphysb.2009.04.017
2009-01-01
In this paper, we demonstrate the LHC discovery potential of new charged vector boson $W_1^{\\pm}$ predicted by the Minimal Higgsless model in the process $pp\\to W_1^{\\pm}qq^{\\prime}\\to W^{\\pm}Z^0qq^\\prime\\to \\ell^{\\pm}\\ell^+\\ell^-\
Charged Higgs boson discovery potential at a 500 GeV e+e- linear collider
International Nuclear Information System (INIS)
The discovery potential for charged Higgs bosons has been studied with full-statistics background simulations for √s = 500 GeV and L = 10 fb-1. For the hadronic decay channels H+H- → c anti s anti cs, tbtb, a microvertex detector is crucial for establishing a signal over the e+e- → t anti t background. A combination with a search in the channels H+H- → c anti sτ-ν, τ+ντ- anti ν allows detection sensitivity for charged Higgs bosons up to a mass of about 210 GeV, independent of the charged Higgs decay modes. Sensitivity regions in the mA-tan β parameter space of the Minimal Supersymmetric extention of the Standard Model (MSSM) are given. (orig.)
Changed Higgs boson discovery potential at a 500 GeV e+e- linear collider
International Nuclear Information System (INIS)
The discovery potential for charged Higgs bosons has been studied with full-statistics background simulations for √s = 500 GeV and L = 10 fb-1. For the hadronic decay channels H+H- → c anti s anti cs, t anti b anti tb, a microvertex detector is crucial for establishing a signal over the e+e- → t anti t background. A combination with a search in the channels H+H- → c anti sτ- anti ν, τ+ντ- anti ν allows detection sensitivity for charged Higgs bosons up to a mass of about 210 GeV, independent of the charged Higgs decay modes. Sensitivity regions in the mA-tan β parameter space of the Minimal Supersymmetric extention of the Standard Model (MSSM) are given. (orig.)
Improving the discovery potential of charged Higgs bosons at Tevatron Run
International Nuclear Information System (INIS)
By exploiting the full process pp-bar→tb-barH-, in place of the standard Monte Carlo procedure of factorising production and decay, pp-bar→tt-bar followed by t-bar→b-barH-, we show how to improve the discovery reach of the Tevatron (Run 2) in charged Higgs boson searches, in the large tan β region. This is achieved in conjunction with dedicated cuts on a 'transverse mass' distribution sensitive to the Higgs boson mass and to 'polarisation' effects in the H- →τ-ν-barτ decay channel. (author)
International Nuclear Information System (INIS)
This work presents a study of the discovery potential for the neutral supersymmetric Higgs bosons h/A/H decaying to τ-pairs with the ATLAS experiment at the LHC. The study is based on Monte Carlo samples which are scaled to state-of-the-art cross sections. The analyses are designed assuming an integrated luminosity of 30 fb-1 and a center-of-mass energy of √(s)=14 TeV. The results are interpreted in the mmaxh benchmark scenario. Two final states are analyzed: The dileptonic channel where the two τ-leptons decay to electrons or muons and the lepton-hadron channel where one τ decays to an electron or muon and the other τ decays to hadrons. The study of the dilepton channel is based completely on the detailed ATLAS simulation, the analysis of the lepton-hadron channel is based on the fast simulation. The collinear approximation is used to reconstruct the Higgs boson mass and its performance is studied. Cuts are optimized in order to discriminate the signal from background and to maximize the discovery potential given a certain Higgs boson mass hypothesis. In the lepton-hadron channel the selection is split into two analyses depending on the number of identified b-jets. Procedures to estimate the dominant backgrounds from data are studied. The shape and normalization of the Z→ττ background are estimated from Z→ll control regions. The t anti t contributions to the signal regions are estimated from t anti t control regions. The individual analyses are combined and sensitivity predictions are made depending on the Higgs boson mass mA and the coupling parameter tan β. The light neutral MSSM Higgs bosons with mA=150 GeV can be discovered when at least tan β=11 is realized in nature. The heavy neutral MSSM Higgs bosons with mA=800 GeV can be discovered for tan β ≥ 44. However, due to the large width of the reconstructed Higgs boson mass and the mass degeneration, only the sum of at least two of the three Higgs boson signals will be visible. (orig.)
CMS Potential for the Higgs Boson Discovery with 1 fb-1
International Nuclear Information System (INIS)
We present the prospects for the early Higgs boson searches at the CMS experiment. We discuss the sensitivity projections for searches for Standard Model and MSSM Higgs bosons with data expected to be collected during 2011 data taking period. We also report some of the 2010 data analyses validating the key aspects of Higgs searches. (author)
Improving the discovery potential of charged Higgs bosons at the Tevatron and large hadron collider
Indian Academy of Sciences (India)
Stefano Moretti
2003-02-01
We outline several improvements to the experimental analyses carried out at Tevatron (Run 2) or simulated in view of the large hadron collider (LHC) that could increase the scope of CDF/D0 and ATLAS/CMS in detecting charged Higgs bosons.
Light Higgs boson discovery from fermion mixing
Aguilar-Saavedra, J A
2006-01-01
We evaluate the LHC discovery potential for a light Higgs boson in t tbar H (-> l nu bbbbjj) production, within the Standard Model and if a new Q=2/3 quark singlet T with a moderate mass exists. In the latter case, T pair production with decays T Tbar -> W+ b H tbar, H t W- bbar -> W+ b W- bbar H provides an important additional source of Higgs bosons giving the same experimental signature. Both analyses are carried out with particle-level simulations of signals and backgrounds. Our estimate for SM Higgs discovery in t tbar H production, 2.25 sigma significance for M_H = 115 GeV and an integrated luminosity of 30 fb^-1, is more pessimistic than previous ones. We show that, if a quark singlet with a mass m_T = 500 GeV exists, the luminosity required for Higgs discovery in this final state is reduced by a factor of 25, and 5 sigma significance can be achieved already with 6 fb^-1. This new Higgs signal will not be seen unless we look for it: with this aim, a new specific final state reconstruction method is pre...
Discovery of the Higgs boson and beyond
International Nuclear Information System (INIS)
This talk is about the Higgs mechanism, the theoretical discovery of which, was awarded the 2013 Nobel Prize. It also discusses the discovery of the Higgs boson at the large hadron collider which provided the experimental proof that made the Nobel prize possible. It covers the implications of these for the quest of unravelling the fundamental laws of nature which seem to govern both, the behavior of the ultra small (subatomic particles) and the ultra large (the cosmos)
The Higgs boson discovery and measurements
International Nuclear Information System (INIS)
The discovery of the Higgs boson at a mass around 125 GeV by the ATLAS and CMS experiments at the LHC collider in 2012 establishes a new landscape in high-energy physics. The analysis of the full data sample collected with pp collisions at centre-of-mass energies of 7 and 8 TeV has allowed for considerable progress since the discovery. A review of the latest results is presented. (authors)
The discovery of the intermediate vector bosons
International Nuclear Information System (INIS)
The discovery of the intermediate vector bosons in 1983 at CERN marked the culmination of a long effort to unify the theory of weak and electromagnetic forces. Here a brief outline of development of the electroweak theory which unifies these forces is given first. Its essential feature is the prediction of the existence of the W+- and Z0 bosons with rest masses of about ninety times the proton mass and lifetimes around 10-24s. Then the experimental methods used at CERN to produce and to detect these very massive and short-lived particles are described. (author)
Discovery of the intermediate W boson
1983-01-01
Press conference on 25 January 1983 when the announcement was made of the discovery of the intermediate W boson at CERN. From right to left: Carlo Rubbia, spokesman of the UA1 experiment; Simon van der Meer, responsible for developing the stochastic cooling technique; Herwig Schopper, Director- General of CERN; Erwin Gabathuler, Research Director at CERN, and Pierre Darriulat, spokesman of the UA2 experiment, whose results confirmed those from Carlo Rubbia's experiment.
International Nuclear Information System (INIS)
In this thesis a method was developed to reconstruct and identify hadronically decaying τ leptons. It was studied using a realistic simulation of the ATLAS detector. The method has become the standard strategy in the ATLAS experiment. The performance was parametrised for the use in the fast detector simulation. In Supersymmetry, if charge-parity (CP) symmetry is assumed, the neutral Higgs bosons are called A for the CP-odd, and H and h for the CP-even states. A study of a search for A/H → ττ was carried out in three production and decay modes A/H → τ(l)τ(h), b anti b A/H → b anti b τ(l)τ(h) and b anti b A/H → b anti b τ(h)τ(h). The analysis was performed using the fast detector simulation updated with the new parametrisation of the identification of τ leptons. If CP is not conserved, the neutral Higgs bosons are ordered in mass and denoted with H1, H2 and H3. A search for H2/3 → H1H1 → b anti b ττ was investigated the first time for the ATLAS experiment assuming CP violation in the Higgs sector of Supersymmetry. From these studies the ATLAS discovery potential in these scenarios was extracted and is shown at the end of this Ph.D. thesis. 2 (orig.)
Study of the Higgs boson discovery potential in the process pp→H/A→μ+μ-/τ+τ- with the ATLAS detector
International Nuclear Information System (INIS)
In this thesis, the discovery potential of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN for the heavy neutral Higgs bosons H/A of theMinimal Supersymmetric extension of the Standard Model of particle physics (MSSM) in the decay channels H/A→τ+τ-→e/μ+X and H/A→μ+μ- has been studied. The ATLAS detector is designed to study the full spectrum of the physics phenomena occuring in the proton-proton collisions at 14 TeV center-of-mass energy and to provide answers to the question of the origin of particle masses and of electroweak symmetry breaking. For the studies, the ATLAS muon spectrometer plays an important role. The spectrometer allows for a precise muon momentum measurement independently of other ATLAS subdetectors. The performance of the muon spectrometer depends strongly on the performance of the muon tracking detectors, the Monitored Drift Tube Chambers (MDT). Computer programs have been developed in order to test and verify the ATLAS muon spectrometer simulation, an essential ingredient for data analysis. In addition, dedicated programs for the monitoring of the quality of the data collected by the muon spectrometer have been developed and tested with data from cosmic ray muons. High-quality cosmic ray muon data have been used for the calibration of the MDT-chambers. A new calibration method, called analytical autocalibration, has been tested. The proposed method achieved the required accuracy of 20 μm in the determination of the space-to-drift-time relationship of the drift tubes of the MDT chambers with only 2000 muon tracks per chamber. Reliable muon detector simulation and calibration are essential for the study of the MSSM Higgs boson decays H/A→τ+τ-→e/μ+X and H/A→μ+μ- and of the corresponding background processes. The signal selection and background rejection requirements have been optimized for maximum signal significance. The following results have been obtained for different assumptions on the MSSM Higgs boson
Prospects for Higgs boson discovery and measurement in the H → τ τ decay mode
International Nuclear Information System (INIS)
We present the potential for measurement of a low-mass Higgs boson at the LHC using WH and ttH production, with the Higgs boson decaying to τ pairs. We find that these modes can enhance discovery and coupling-ratio sensitivity with 30/fb and 300/fb of 14 TeV collision data, respectively, for a Higgs boson with mass between 115 and 135 GeV. (authors)
The Higgs boson discovery at the Large Hadron Collider
Wolf, Roger
2015-01-01
This book provides a comprehensive overview of the field of Higgs boson physics. It offers the first in-depth review of the complete results in connection with the discovery of the Higgs boson at CERN’s Large Hadron Collider and based on the full dataset for the years 2011 to 2012. The fundamental concepts and principles of Higgs physics are introduced and the important searches prior to the advent of the Large Hadron Collider are briefly summarized. Lastly, the discovery and first mensuration of the observed particle in the course of the CMS experiment are discussed in detail and compared to the results obtained in the ATLAS experiment.
Zhao, Xiaoran; Li, Zhao; Yan, Qi-Shu
2016-01-01
We explore the discovery potential of Higgs pair production at a 100 TeV collider via full leptonic mode. The same mode can be explored at the LHC when Higgs pair production is enhanced by new physics. We examine two types of fully leptonic final states and propose a partial reconstruction method. The reconstruction method can reconstruct some kinematic observables. It is found that the $m_{T2}$ variable determined by this reconstruction method and the reconstructed visible Higgs mass are important and crucial to discriminate the signal and background events. It is also noticed that a new variable, denoted as $\\Delta m$ which is defined as the mass difference of two possible combinations, is very useful as a discriminant. We also investigate the interplay between the direct measurements of $t\\bar{t} h$ couplings and other related couplings and trilinear Higgs coupling at hadron colliders and electron-positron colliders.
The discovery and measurements of a Higgs boson
International Nuclear Information System (INIS)
The discovery of a Higgs-like boson with a mass of approximately 125 GeV by the ATLAS and CMS experiments at the Large Hadron Collider was announced at CERN on 4 July 2012. The data-set of 5 fb−1 of proton–proton collisions with √s=7 TeV collected during 2011 and 6 fb−1 with √s=8 TeV collected in 2012 up to the July discovery was supplemented by an additional 15 fb−1 of data with √s=8 TeV collected during the rest of 2012. The measurements of the properties of the new boson with the combined data-set have substantially strengthened the evidence that this new particle is indeed the Higgs boson predicted to exist as a consequence of the Brout–Englert–Higgs-mechanism that takes responsibility for generating masses of fundamental particles and for the electroweak symmetry breaking. (paper)
Technicolor with Scalar Doublet After the Discovery of Higgs Boson
Zheng, Sibo
2013-01-01
The SM-like Higgs boson with mass of 125 GeV discovered at the LHC is subject to a natural interpretation of electroweak symmetry breaking. As a successful theory in offering this naturalness, technicolor with a fundamental scalar doublet and two colored techni-scalars is proposed after the discovery of SM-like Higgs boson. At present status, the model can be consistent with both the direct and indirect experimental limits. In particular, the consistency with precision electroweak measurements is realized by the colored techni-scalars, which give rise to a large {\\it negative} contribution to $S$ parameter. It is also promising to detect techni-pions and colored techni-scalars at the 14-TeV LHC.
Discovery potential of the Standard Model Higgs at the LHC
International Nuclear Information System (INIS)
We discuss the discovery potential of a Standard Model Higgs at the LHC. We focus on a channel of the Higgs HSM0->ττ in a vector boson fusion process, where one tau decays leptonically and the other hadronically. This channel plays an important role for the Higgs discovery in the low mass region (115HSM0<140GeV). We describe a method of hadronic tau identification, which is one of key issues for this discovery, at ATLAS
Energy Technology Data Exchange (ETDEWEB)
Dedes, Georgios
2008-04-22
In this thesis, the discovery potential of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN for the heavy neutral Higgs bosons H/A of theMinimal Supersymmetric extension of the Standard Model of particle physics (MSSM) in the decay channels H/A{yields}{tau}{sup +}{tau}{sup -}{yields}e/{mu}+X and H/A{yields}{mu}{sup +}{mu}{sup -} has been studied. The ATLAS detector is designed to study the full spectrum of the physics phenomena occuring in the proton-proton collisions at 14 TeV center-of-mass energy and to provide answers to the question of the origin of particle masses and of electroweak symmetry breaking. For the studies, the ATLAS muon spectrometer plays an important role. The spectrometer allows for a precise muon momentum measurement independently of other ATLAS subdetectors. The performance of the muon spectrometer depends strongly on the performance of the muon tracking detectors, the Monitored Drift Tube Chambers (MDT). Computer programs have been developed in order to test and verify the ATLAS muon spectrometer simulation, an essential ingredient for data analysis. In addition, dedicated programs for the monitoring of the quality of the data collected by the muon spectrometer have been developed and tested with data from cosmic ray muons. High-quality cosmic ray muon data have been used for the calibration of the MDT-chambers. A new calibration method, called analytical autocalibration, has been tested. The proposed method achieved the required accuracy of 20 {mu}m in the determination of the space-to-drift-time relationship of the drift tubes of the MDT chambers with only 2000 muon tracks per chamber. Reliable muon detector simulation and calibration are essential for the study of the MSSM Higgs boson decays H/A{yields}{tau}{sup +}{tau}{sup -}{yields}e/{mu}+X and H/A{yields}{mu}{sup +}{mu}{sup -} and of the corresponding background processes. The signal selection and background rejection requirements have been optimized for maximum signal
Discovery of the Higgs boson by the ATLAS and CMS experiments at the LHC
Wang, HaiChen
2014-01-01
The Standard Model (SM) Higgs boson was predicted by theorists in the 1960s during the development of the electroweak theory. Prior to the startup of the CERN Large Hadron Collider (LHC), experimental searches found no evidence of the Higgs boson. In July 2012, the ATLAS and CMS experiments at the LHC reported the discovery of a new boson in their searches for the SM Higgs boson. Subsequent experimental studies have revealed the spin-0 nature of this new boson and found its couplings to SM particles consistent to those of a Higgs boson. These measurements confirmed the newly discovered boson is indeed a Higgs boson. More measurements will be performed to compare the properties of the Higgs boson with the SM predictions.
Khosa, Charanjit K.; Pandita, P. N.
2016-06-01
We consider the measurement of the trilinear couplings of the neutral Higgs bosons in the minimal supersymmetric standard model (MSSM) at a high energy e+e‑ linear collider in the light of the discovery of a Higgs boson at the CERN Large Hadron Collider (LHC). We identify the state observed at the LHC with the lightest Higgs boson (h0) of the MSSM, and impose the constraints following from this identification, as well as other experimental constraints on the MSSM parameter space. In order to measure trilinear neutral Higgs couplings, we consider different processes where the heavier Higgs boson (H0) of the MSSM is produced in electron-positron collisions, which subsequently decays into a pair of lighter Higgs boson. We identify the regions of the MSSM parameter space where it may be possible to measure the trilinear couplings of the Higgs boson at a future electron-positron collider. A measurement of the trilinear Higgs couplings is a crucial step in the construction of the Higgs potential, and hence in establishing the phenomena of spontaneous symmetry breaking in gauge theories.
Khosa, Charanjit K
2016-01-01
We consider the measurement of the trilinear couplings of the neutral Higgs bosons in the Minimal Supersymmetric Standard Model~(MSSM) at a high energy $e^+ e^-$ linear collider in the light of the discovery of a Higgs boson at the CERN Large Hadron Collider~(LHC). We identify the state observed at the LHC with the lightest Higgs boson~($h^0$) of the MSSM, and impose the constraints following from this identification, as well as other experimental constraints on the MSSM parameter space. In order to measure trilinear neutral Higgs couplings, we consider different processes where the heavier Higgs boson ($H^0$) of the MSSM is produced in electron-positron collisions, which subsequently decays into a pair of lighter Higgs bosons. We identify the regions of the MSSM parameter space where it may be possible to measure the trilinear couplings of the Higgs boson at a future electron-positron collider. A measurement of the trilinear Higgs couplings is a crucial step in the construction of the Higgs potential, and he...
1994-01-01
Bosonization is a useful technique for studying systems of interacting fermions in low dimensions. It has applications in both particle and condensed matter physics.This book contains reprints of papers on the method as used in these fields. The papers range from the classic work of Tomonaga in the 1950's on one-dimensional electron gases, through the discovery of fermionic solitons in the 1970's, to integrable systems and bosonization on Riemann surfaces. A four-chapter pedagogical introduction by the editor should make the book accessible to graduate students and experienced researchers alik
Smartphones: A Potential Discovery Tool
Starkweather, Wendy; Stowers, Eva
2009-01-01
The anticipated wide adoption of smartphones by researchers is viewed by the authors as a basis for developing mobile-based services. In response to the UNLV Libraries’ strategic plan’s focus on experimentation and outreach, the authors investigate the current and potential role of smartphones as a valuable discovery tool for library users.
Low-Data Investigation of Higgs Boson Discovery at the LHC
Scoby, Cheyne M
2006-01-01
The Standard Model (SM) remains as a complete and effective tool for understanding fundamental particles and their interactions. There is only one particle that the model predicts that has not yet been discovered. The Higgs boson is required as part of the mechanism behind electroweak symmetry breaking, and explains how the weak vector bosons, as well as the charged quarks and leptons gain mass, proportional to their coupling to the Higgs field. The SM predicts many properties of the Higgs, but cannot give a precise value to its mass. Experiment and theoretical arguments have put limits on the Higgs mass to within 114.7 GeV/c2 < MH < 1000 GeV/c2. The Large Hadron Collider at CERN will provide access to a new energy regime that will offer many channels for a potential discovery of the Higgs. In the Compact Muon Solenoid (CMS) detector experiment, the “Golden mode” for Higgs discovery features decay to two Z0, with both Z0 decaying to leptonic final states. Full reconstruction analyses suffer from the...
The theoretical physics ecosystem behind the discovery of the Higgs boson
Wells, James D
2016-01-01
The discovery of the Higgs boson in 2012 was one of the most significant developments of science in the last half century. A simplified history has Peter Higgs positing it in the mid-1960s followed by a long wait while experimentalists progressively turned up collider energies until it appeared several decades later. However, in order for both the hypothesis and the experimental discovery to occur, a vast and complex theory ecosystem had to thrive in the years before Higgs's hypothesis and in the years that followed, building up to its discovery. It is further claimed that the Higgs boson hypothesis was an immoderate speculation, and therefore faith in theory argumentation and speculation was mandatory for the discovery program to proceed and reach its fulfillment. The Higgs boson could not have been discovered experimentally by accident.
Discovery and Characterization of a Higgs boson using four-lepton events from the CMS
Energy Technology Data Exchange (ETDEWEB)
Martin, Christopher Blake [Johns Hopkins Univ., Baltimore, MD (United States)
2015-07-01
A new particle decaying to a pair of vector bosons was discovered in 2012 by the ATLAS and CMS experiments at the Large Hadron Collider. In the wake of this discovery a rush of measurements was made to characterize this particle. The fourlepton final state has been instrumental in both the discovery and characterization of this new particle. With only about 20 events seen in the resonance peak at 125 GeV the CMS experiment has been able to make considerable progress in characterizing the Higgs-like boson using the wealth of information in this final state in concert with other decay modes. In addition to the search for this new boson we present three recent results in the study of the Higgs-like boson properties: studies of the production mode, total width, and spin-parity quantum numbers.
The Higgs boson and the physics of $WW$ scattering before and after Higgs discovery
Szleper, Michał
2014-01-01
This work presents a comprehensive overview of the physics of vector boson scattering (VBS) in the dawn of Run 2 of the Large Hadron Collider (LHC). Recalled here are some of its most basic physics principles, the historical relation between vector boson scattering and the Higgs boson, then discussed is the physics of VBS processes after Higgs discovery, and the prospects for future VBS measurements at the LHC and beyond. This monograph reviews the work of many people, including previously published theoretical work as well as experimental results, but also contains a portion of original simulation-based studies that have not been published before.
The search and discovery of the Higgs boson a brief introduction to particle physics
Flores Castillo, Luis Roberto
2015-01-01
This book provides a general description of the search for and discovery of the Higgs boson (particle) at CERN's Large Hadron Collider. The goal is to provide a relatively brief overview of the issues, instruments and techniques relevant for this search; written by a physicist who was directly involved. The Higgs boson may be the one particle that was studied the most before its discovery and the story from postulation in 1964 to detection in 2012 is a fascinating one. The story is told here while detailing the fundamentals of particle physics.
High-energy vector boson scattering after the Higgs discovery
International Nuclear Information System (INIS)
Weak vector boson scattering (VBS)at high energies will be one of the key measurements in the upcoming LHC runs. It is very sensitive to any new physics associated with electroweak symmetry breaking. But a conventional EFT analysis will fail at high energies, especially in the presence of the light 125 GeV Higgs boson. In this talk I present how to extend the EFT to a simplified model by adding additional resonances to VBS and therefore increase the energy validity of the theoretical description. Furthermore I introduce the T-matrix unitarization scheme as an extension of the K-matrix unitarization prescription. It provides an asymptotically consistent reference model, which has been matched to the low-energy effective theory of arbitrary non-perturbative and perturbative models.
High-energy vector boson scattering after the Higgs discovery
Energy Technology Data Exchange (ETDEWEB)
Kilian, Wolfgang; Sekulla, Marco [University of Siegen, Siegen (Germany); Ohl, Thorsten [Wuerzburg University, Wuerzburg (Germany); Reuter, Juergen [DESY, Hamburg (Germany)
2015-07-01
Weak vector boson scattering (VBS)at high energies will be one of the key measurements in the upcoming LHC runs. It is very sensitive to any new physics associated with electroweak symmetry breaking. But a conventional EFT analysis will fail at high energies, especially in the presence of the light 125 GeV Higgs boson. In this talk I present how to extend the EFT to a simplified model by adding additional resonances to VBS and therefore increase the energy validity of the theoretical description. Furthermore I introduce the T-matrix unitarization scheme as an extension of the K-matrix unitarization prescription. It provides an asymptotically consistent reference model, which has been matched to the low-energy effective theory of arbitrary non-perturbative and perturbative models.
Resummation of Goldstone boson contributions to the MSSM effective potential
Kumar, Nilanjana; Martin, Stephen P.
2016-07-01
We discuss the resummation of the Goldstone boson contributions to the effective potential of the minimal supersymmetric Standard Model. This eliminates the formal problems of spurious imaginary parts and logarithmic singularities in the minimization conditions when the tree-level Goldstone boson squared masses are negative or approach zero. The numerical impact of the resummation is shown to be almost always very small. We also show how to write the two-loop minimization conditions so that Goldstone boson squared masses do not appear at all, and so that they can be solved without iteration.
Resummation of Goldstone boson contributions to the MSSM effective potential
Kumar, Nilanjana
2016-01-01
We discuss the resummation of the Goldstone boson contributions to the effective potential of the Minimal Supersymmetric Standard Model (MSSM). This eliminates the formal problems of spurious imaginary parts and logarithmic singularities in the minimization conditions when the tree-level Goldstone boson squared masses are negative or approach zero. The numerical impact of the resummation is shown to be almost always very small. We also show how to write the two-loop minimization conditions so that Goldstone boson squared masses do not appear at all, and so that they can be solved without iteration.
Higgs bosons in supersymmetric model with CP-violating potential
Oshimo, Noriyuki
2015-01-01
In the supersymmetric standard model which is not minimal, the Higgs potential does not conserve CP symmetry generally. Assuming that there exists an SU(2)-triplet Higgs field, we discuss resultant CP-violating effects on the Higgs bosons. The experimentally observed Higgs boson, which should be CP-even in the standard model, could decay into two photons of CP-odd polarization state non-negligibly. For the second lightest Higgs boson, in sizable region of parameter space, the dominant decay m...
Particle Physics after the Higgs-Boson Discovery: Opportunities for the Large Hadron Collider
Quigg, Chris
2015-01-01
The first run of the Large Hadron Collider at CERN brought the discovery of the Higgs boson, an apparently elementary scalar particle with a mass of 125 GeV, the avatar of the mechanism that hides the electroweak symmetry. A new round of experimentation is beginning, with the energy of the proton--proton colliding beams raised to 6.5 TeV per beam, from 4 TeV at the end of the first run. This article summarizes what we have learned about the Higgs boson, and calls attention to some issues that will be among our central concerns in the near future.
Discovery and Characterization of a Higgs boson using four-lepton events from the CMS experiment
AUTHOR|(SzGeCERN)678846
2015-01-01
A new particle decaying to a pair of vector bosons was discovered in 2012 by the ATLAS and CMS experiments at the Large Hadron Collider. In the wake of this discovery a rush of measurements was made to characterize this particle. The four-lepton final state has been instrumental in both the discovery and characterization of this new particle. With only about 20 events seen in the resonance peak at 125GeV the CMS experiment has been able to make considerable progress in characterizing the Higgs-like boson using the wealth of information in this final state in concert with other decay modes. In addition to the search for this new boson we present three recent results in the study of the Higgs-like boson properties: studies of the production mode, total width, and spin-parity quantum numbers. First we present the search for this new resonance using the H to ZZ to 4l decay channel. Then we discuss the production mode measurement using this final state. Next, we present two results that provided breakthroughs in t...
The discovery of the Higgs boson at the Large Hadron Collider
Nisati, A.; Tonelli, G.
2015-11-01
This paper summarises the work done by the ATLAS and CMS collaborations, and by the teams of the Large Hadron Collider at CERN, that led to the discovery of a new particle, with mass near 125GeV and properties consistent with the ones predicted for the Standard Model Higgs boson. An overview of the Standard Model, with a description of the role of the Higgs boson in the theory, and a summary of the searches for this particle prior to the LHC operations is also given. The paper presents the results obtained by ATLAS and CMS from the analysis of the full data set produced in the first physics run of LHC. After a short discussion on the implications of the discovery, the future prospects for the precision study of the new particle are lastly discussed.
The Standard Model Higgs : Discovery Potentials and Branching Fraction Measurements at the NLC
Sachwitz, M.; Schreiber, H. J.; Shichanin, S.
1997-01-01
We discuss discovery potentials for a 140 GeV Standard Model Higgs boson produced in e+e- collisions at 360 GeV, including all potential irreducible and reducible background contributions. In the second part of the study, we estimate the uncertainties expected for the branching fractions of the Higgs into bb-bar, tau+tau-, WW* and into cc-bar+gg including a realistic error estimation of the inclusive bremsstrahlung Higgs production cross section.
Boson-exchange nucleon-nucleon potential and nuclear structure
International Nuclear Information System (INIS)
A fully momentum-dependent one-boson-exchange potential is derived which takes into account the mesons, π, eta, sigma, rho, ω and phi. Scattering bound states and nuclear matter properties are studied in momentum space. The use of such potential is shown to be as easy as the use of more simple phenomenological interactions. In nuclear matter the formalism of Bethe-Goldstone is chosen to compute the binding energy versus density in the approximation of two-body and three-body correlations. The three-body correlated wave function obtained is then used
Forward-Backward Asymmetry as a Discovery Tool for Z' Bosons at the LHC
Accomando, E; Fiaschi, J; Mimasu, K; Moretti, S; Shepherd-Themistocleous, C
2015-01-01
The Forward-Backward Asymmetry (AFB) in Z' physics is commonly only perceived as the observable which possibly allows one to interpret a Z' signal by distinguishing different models of such (heavy) spin-1 bosons. In this paper, we examine the potential of AFB in setting bounds on or even discovering a Z' boson at the Large Hadron Collider (LHC) and show that it might be a powerful tool for this purpose. We analyse two different scenarios: Z' bosons with a narrow and wide width, respectively. We find that, in the first case, the significance of the AFB search can be comparable with that of the bump search usually adopted by the experimental collaborations; however, being a ratio of (differential) cross sections the AFB has the advantage of reducing systematical errors. In the second case, the AFB search can win over the bump search in terms of event shape, as the structure of the AFB distribution as a function of the invariant mass of the reconstructed Z'boson could nail down the new broad resonance much bette...
Influence of Finite Chemical Potential on Critical Boson Mass in QED3
Institute of Scientific and Technical Information of China (English)
ZHANG Yun-Qiang; LI Zhen; FENG Hong-Tao
2007-01-01
Using the coupled Dyson-Schwinger equation for the fermion propagator at finite chemical potential μ,we investigate the fermion chiral condensate when the gauge boson mass is nonzero in QED3. We show that the chiral symmetry restores when the boson mass is large enough, and the critical boson mass depends little on μ.
Light charged Higgs discovery potential of CMS in the H± → τντ decay with single lepton trigger
International Nuclear Information System (INIS)
In this note the CMS discovery potential for the light charged Higgs boson in the minimal supersymmetric standard model framework is presented. Different Higgs boson production mechanisms were studied to cover the mass range 125 H± 2. The analysis is based on the CMS full simulation and reconstruction. Systematic uncertainties on the background determination are included. It is shown that the systematic uncertainties reduce the observability of H± mainly at low tan β. Finally the 5σ discovery contour for an integrated luminosity of 30 fb-1 is presented. (research note from collaboration)
Nonlinear boson exchange potentials from quantum field theory
International Nuclear Information System (INIS)
To calculate scattering amplitudes in the boson exchange model for nucleon-nucleon scattering we make use of a relativistic nonlinear Quantum Field Theory for self interacting pseudoscalar and vector mesons. The boson fields satisfy a modified Klein-Gordon equation which contains nonlinear currents. In particular we select currents of Sine Gordon and polynomial type which have known solitary wave solutions. The propagator for these fields contains a series of Feynman propagators with different masses and energy dependent factors predicted by the form of the interaction current. The pseudoscalar and vector fields are determined by the known pion and rho meson masses and two self interaction coupling constants. No form factors or other meson masses of the conventional OBEP models enter. The nonlinearity of this model describes quantitively the three regions of nucleon-nucleon potentials, the long range OPEP tail, the medium range attraction as well as the short range repulsion. We compare our results with the Bonn-B model. A crucial test of the nonlinear currents are production processes above 300MeV
The discovery potential of laser polarization experiments
International Nuclear Information System (INIS)
Currently, a number of experiments are searching for vacuum magnetic birefringence and dichroism, i.e. for dispersive and absorptive features in the propagation of polarized light along a transverse magnetic field in vacuum. In this note we calculate the Standard Model contributions to these signatures, thereby illuminating the discovery potential of such experiments in the search for new physics. We discuss the three main sources for a Standard Model contribution to a dichroism signal: photon splitting, neutrino pair production and production of gravitons. (orig.)
AFB as a discovery tool for Z' bosons at the LHC
Accomando, E.; Belyaev, A.; Fiaschi, J.; Mimasu, K.; Moretti, S.; Shepherd-Themistocleous, C.
2016-07-01
The Forward-Backward Asymmetry (AFB) in Z' physics is commonly only perceived as the observable which possibly allows one to interpret a Z' signal by distinguishing different models of such (heavy) spin-1 bosons. In this article, we examine the potential of AFB in setting bounds on or even discovering a Z' at the Large Hadron Collider (LHC) and show that it might be a powerful tool for this purpose. We analyze two different scenarios: Z' s with a narrow and wide width, respectively. We find that in both cases AFB can complement the cross section in accessing Z' signals.
$A_{FB}$ as a discovery tool for $Z^\\prime$ bosons at the LHC
Accomando, E; Fiaschi, J; Mimasu, K; Moretti, S; Shepherd-Themistocleous, C
2015-01-01
The Forward-Backward Asymmetry (AFB) in $Z^\\prime$ physics is commonly only perceived as the observable which possibly allows one to interpret a $Z^\\prime$ signal by distinguishing different models of such (heavy) spin-1 bosons. In this article, we examine the potential of AFB in setting bounds on or even discovering a $Z^\\prime$ at the Large Hadron Collider (LHC) and show that it might be a powerful tool for this purpose. We analyze two different scenarios: $Z^\\prime$s with a narrow and wide width, respectively. We find that in both cases AFB can complement the cross section in accessing $Z^\\prime$ signals.
Accomando, Elena; Fiaschi, Juri; Mimasu, Ken; Moretti, Stefano; Shepherd-Themistocleous, Claire
2015-01-01
The Forward-Backward Asymmetry (AFB) in Z' physics is commonly only thought of as an observable which possibly allows one to profiling a Z' signal by distinguishing different models embedding such (heavy) spin-1 bosons. In this brief review, we examine the potential of AFB in setting bounds on or even discovering a Z' at the Large Hadron Collider (LHC) and proof that it might be a powerful tool for this purpose. We analyse two different scenarios: Z's with a narrow and wide width, respectively. We find that, in both cases, AFB can complement the conventional searches in accessing Z' signals traditionally based on cross section measurements only.
$3d$ fermion-boson map with imaginary chemical potential
Filothodoros, E G; Vlachos, N D
2016-01-01
We study the three-dimensional $U(N)$ Gross-Neveu and CP$^{N-1}$ models in the canonical formalism with fixed $U(1)$ charge. For large-$N$ this is closely related to coupling the models to abelian Chern-Simons in a monopole background. We show that the presence of the imaginary chemical potential for the $U(1)$ charge makes the phase structure of the models remarkably similar. We calculate their respective large-$N$ free energy densities and show that they are mapped into each other in a precise way. Intriguingly, the free energy map involves the Bloch-Wigner function and its generalizations introduced by Zagier. We expect that our results are connected to the recently discussed $3d$ bosonization.
ATLAS discovery potential of supersymmetry with tau final states
International Nuclear Information System (INIS)
Supersymmetry is a theory that postulates a symmetry between bosons and fermions in order to solve some of the problems that are present in our current understanding of particles and their interactions. When the Large Hadron Collider will start taking data, supersymmetric particles could be created leading to relatively long cascade decays involving multiple jets, some leptons and large missing transverse energy. Depending on which parameters define the supersymmetric theory, the third generation quarks and leptons could play an important role and also help to characterise the excess with respect to the Standard Model predictions. In this talk, an inclusive search for supersymmetry using taus in the final state is shown. Hadronically decaying taus are challenging objects to identify and to reject against multijet processes and electrons. Some proposed identification cuts are shown together with the current ATLAS approach to reduce the Standard Model background contribution. The discovery potential with this set of cuts and some ideas on how to improve it are also presented. (orig.)
Forward-backward asymmetry as a discovery tool for Z' bosons at the LHC
Accomando, Elena; Belyaev, Alexander; Fiaschi, Juri; Mimasu, Ken; Moretti, Stefano; Shepherd-Themistocleous, Claire
2016-01-01
The Forward-Backward Asymmetry (AFB) in Z' physics is commonly only perceived as the observable which possibly allows one to interpret a Z' signal appearing in the Drell-Yan channel by distinguishing different models of such (heavy) spin-1 bosons. In this paper, we revisit this issue, showing that the absence of any di-lepton rapidity cut, which is commonly used in the literature, can enhance the potential of the observable at the LHC. We moreover examine the ability of AFB in setting bounds on or even discovering a Z' at the Large Hadron Collider (LHC) concluding that it may be a powerful tool for this purpose. We analyse two different scenarios: Z'-bosons with a narrow and wide width, respectively. We find that, in the first case, the significance of the AFB search can be comparable with that of the `bump' search usually adopted by the experimental collaborations; however, in being a ratio of (differential) cross sections, the AFB has the advantage of reducing experimental systematics as well as theoretical errors due to PDF uncertainties. In the second case, the AFB search can outperform the bump search in terms of differential shape, meaning the AFB distribution may be better suited for new broad resonances than the event counting strategy usually adopted in such cases.
Search for the Higgs boson: a statistical adventure of exclusion and discovery
International Nuclear Information System (INIS)
The 40 years old Standard Model, the theory of particle physics, seems to describe all experimental data very well. All of its elementary particles were identified and studied apart from the Higgs boson until 2012. For decades many experiments were built and operated searching for it, and finally, the two main experiments of the Large Hadron Collider at CERN, CMS and ATLAS, in 2012 observed a new particle with properties close to those predicted for the Higgs boson. In this talk we describe the search process: the exclusion of the Higgs boson at LEP, the Large Electron Positron collider, and the observation at LHC of a new boson with properties close to those predicted for the Higgs boson of the Standard Model. We try to pay special attention on the statistical methods used.
Large Hadron Collider's discovery of a new particle with Higgs boson properties
International Nuclear Information System (INIS)
We outline the results of the ATLAS and CMS collaborations, which announced a new particle with properties consistent with those expected from the Standard Model Higgs boson. At a qualitative level, we describe the roles played by the Englert–Brout–Higgs field and the Higgs boson in the theory of fundamental particles and their interactions. We also discuss prospects for theoretical and experimental studies in the new area of elementary particle physics. (physics of our days)
Relationship of field-theory based single-boson-exchange potentials to static ones
International Nuclear Information System (INIS)
It is shown that field-theory based single-boson-exchange potentials cannot be identified to those of the Yukawa or Coulomb type that are currently inserted in the Schroedinger equation. The potential which is obtained rather correspond to this current single-boson-exchange potential corrected for the probability that the system under consideration is in a two-body component, therefore missing contributions due to the interaction of these two bodies while bosons are exchanged. The role of these contributions, which involve at least two-boson exchanges, is examined. The conditions that allow one to recover the usual single-boson-exchange potential are given. It is shown that the present results have some relation: (i) to the failure of the Bethe-Salpeter equation in reproducing the Dirac or Klein-Gordon equations in the limit where one of the constituents has a large mass, (ii) to the absence of corrections of relative order α log 1/α to a full calculation of the binding energy in the case of neutral massless bosons or (iii) to large corrections of wave-functions calculated perturbatively in some light-front approaches. Refs. 48 (author)
The Electroweak Fit of the Standard Model after the Discovery of a New Boson at the LHC
Baak, M
2012-01-01
In view of the discovery of a new boson by the ATLAS and CMS Collaborations at the LHC, we present an update of the global Standard Model (SM) fit to electroweak precision data. Assuming the new particle to be the SM Higgs boson, all fundamental parameters of the SM are known allowing, for the first time, to overconstrain the SM at the electroweak scale and assert its validity. Including the effects of radiative corrections and the experimental and theoretical uncertainties, the global fit exhibits a p-value of 0.07. The mass measurements by ATLAS and CMS agree within 1.3sigma with the indirect determination M_H=(94 +25 -22) GeV. Within the SM the W boson mass and the effective weak mixing angle can be accurately predicted to be M_W=(80.359 +- 0.011) GeV and sin^2(theta_eff^ell)=(0.23150 +- 0.00010) from the global fit. These results are compatible with, and exceed in precision, the direct measurements. For the indirect determination of the top quark mass we find m_t=(175.8 +2.7 -2.4) GeV, in agreement with t...
Discovery potential for heavy t-tbar resonances in dilepton+jets final states
Iashvili, Ia; Kharchilava, Avto; Prosper, Harrison B
2013-01-01
We examine the prospects for probing heavy top quark-antiquark (t-tbar) resonances at the upgraded LHC in pp collisions at $\\root_s = 14 TeV. Heavy t-tbar resonances (Z' bosons) are predicted by several theories that go beyond the standard model. We consider scenarios in which each top quark decays leptonically, either to an electron or a muon, and the data sets correspond to integrated luminosities of \\int L dt = 300 /fb and \\int L dt = 3000 /fb. We present the expected 5-sigma discovery potential for a Z' resonance as well as the expected upper limits at 95% C.L. on the Z' production cross section and mass in the absence of a discovery.
Is the New Resonance Spin 0 or 2? Taking a Step Forward in the Higgs Boson Discovery
Alves, Alexandre
2012-01-01
The observation of a new boson of mass $\\sim 125\\gev$ at the CERN LHC may finally have revealed the existence of a Higgs boson. Now we have the opportunity to scrutinize its properties, determining its quantum numbers and couplings to the standard model particles, in order to confirm or not its discovery. We show that by the end of the 8 TeV run, combining the entire data sets of ATLAS and CMS, it will be possible to discriminate between the following discovery alternatives: a scalar $J^P=0^+$ or a tensor $J^P=2^+$ particle with minimal couplings to photons, at a $5\\sigma$ statistical confidence level at least, using only diphotons events. Our results are based on the calculation of a center-edge asymmetry measure of the reconstructed {\\it sPlot} scattering polar angle of the diphotons. The results based on asymmetries are shown to be rather robust against systematic uncertainties with comparable discrimination power to a log likelihood ratio statistic.
Energy Technology Data Exchange (ETDEWEB)
Bimbot, St
2006-10-15
The first chapter presents the theoretical background on which the Higgs mechanism is based within the framework of the standard model. The second chapter reviews the past and present attempts aiming at the discovery of the Higgs boson. The specific features of the Large Hadron Collider (LHC) and of one of its detector: the CMS (Compact Muon Solenoid) detector are given in the third chapter. The author details the track detector and the ECAL electronic calorimeter that are key components of CMS in the detection of the Higgs boson via the following decay channel: H {yields} ZZ{sup *} {yields} 2e{sup +}2e{sup -} (where Z and Z{sup *} represents the Z{sup O} boson in a real state and in a virtual state respectively). The chapters 4 and 5 are dedicated to the calibration of the ECAL calorimeter via the use of an electron beam and to the triggering system. The data analysis that will lead to the reconstruction of the events detected by CMS is presented in the chapter 6. The last chapter is devoted to the optimization of the extraction of the Higgs boson signal from an abundant background noise. (A.C.)
Discovery limit of the charged Higgs boson via top quark decay at future hadron colliders
International Nuclear Information System (INIS)
We study the kinematic cuts which can be used to enhance the charged Higgs signal over the W boson background, for mH±>mW, in the decay of a heavy top quark at LHC energy. With suitable cuts it is possible to ensure a sizeable signal and a signal-to-background ratio > or approx.1 up to mH±≅mt-20 GeV, which hold throughout the allowed coupling parameter (tan β) space in the minimal SUSY model. Thus one should be able to search for the charged Higgs boson to within 20 GeV of the parent top quark mass at the LHC/SSC colliders, i.e., up to 130 GeV for mt≅150 GeV, going up to 180 GeV for mt≅200 GeV. (orig.)
Constrained Supersymmetry after the Higgs Boson Discovery: A global analysis with Fittino
Bechtle, Philip; Dreiner, Herbert K; Hamer, Matthias; Krämer, Michael; O'Leary, Ben; Porod, Werner; Prudent, Xavier; Sarrazin, Björn; Stefaniak, Tim; Uhlenbrock, Mathias; Wienemann, Peter
2013-01-01
We present preliminary results from the latest global fit analysis of the constrained minimal supersymmetric standard model (CMSSM) performed within the Fittino framework. The fit includes low-energy and astrophysical observables as well as collider constraints from the non-observation of new physics in supersymmetric searches at the LHC. Furthermore, the Higgs boson mass and signal rate measurements from both the LHC and Tevatron experiments are included via the program HiggsSignals. Although the LHC exclusion limits and the Higgs mass measurements put tight constraints on the viable parameter space, we find an acceptable fit quality once the Higgs signal rates are included.
Topological phases of two-component bosons in species-dependent artificial gauge potentials
Wu, Ying-Hai; Shi, Tao
2016-08-01
We study bosonic atoms with two internal states in artificial gauge potentials whose strengths are different for the two components. A series of topological phases for such systems is proposed using the composite fermion theory and the parton construction. It is found in exact diagonalization that some of the proposed states may be realized for simple contact interaction between bosons. The ground states and low-energy excitations of these states are modeled using trial wave functions. The effective field theories for these states are also constructed and reveal some interesting properties.
The one-boson exchange potential and the shell-model of mass 18 nuclei
International Nuclear Information System (INIS)
A shell model calculation of spectra of mass 18 nuclei is performed using as nucleon-nucleon interaction the momentum space one-boson exchange potentials. The calculations were done using the Brueckuer reaction G-matrix bare matrix elements only and bare plus core polarization
Influence of trapping potentials on the phase diagram of bosonic atoms in optical lattices
Giampaolo, S. M.; Illuminati, F.; Mazzarella, G.; De Siena, S.
2004-01-01
We study the effect of external trapping potentials on the phase diagram of bosonic atoms in optical lattices. We introduce a generalized Bose-Hubbard Hamiltonian that includes the structure of the energy levels of the trapping potential, and show that these levels are in general populated both at finite and zero temperature. We characterize the properties of the superfluid transition for this situation and compare them with those of the standard Bose-Hubbard description. We briefly discuss s...
Flavor Nuclei and One-Boson-Exchange Potentials
Bando, H.; Nagata, S.
1983-02-01
Binding energies of a flavour baryon, Λ(strange), Λc(charmed) and Λb(beauty), in nuclear matter and in the α-particle are investigated within the framework of the lowest-order Brueckner theory by employing the OBE potentials derived on the basis of the Nijmegen model D interaction.
Ribas, M O; Devecchi, F P; Kremer, G M
2015-01-01
In this work we investigate a model for the early Universe in a Bianchi type-I metric, where the sources of the gravitational field are a fermionic and a bosonic field, interacting through a Yukawa potential, following the standard model of elementary particles. It is shown that the fermionic field has a negative pressure, while the boson has a small positive pressure. The fermionic field is the responsible for an accelerated regime at early times, but since the total pressure tends to zero for large times, a transition to a decelerated regime occurs. Here the Yukawa potential answers for the duration of the accelerated regime, since by decreasing the value of its coupling constant the transition accelerated-decelerated occurs in later times. The isotropization which occurs for late times is due to the presence of the fermionic field as one of the sources of the gravitational field.
Martin, Stephen P.
2002-01-01
I present a method for accurately calculating the pole mass of the lightest Higgs scalar boson in supersymmetric extensions of the Standard Model, using a mass-independent renormalization scheme. The Higgs scalar self-energies are approximated by supplementing the exact one-loop results with the second derivatives of the complete two-loop effective potential in Landau gauge. I discuss the dependence of this approximation on the choice of renormalization scale, and note the existence of partic...
The Higgs Boson Mass from Three-loop Effective Potential of Massless Standard Model
Alrebdi, H I; Barakat, T
2016-01-01
The effective potential of massless standard model (SM) is calculated up to three-loop order. The stability of the effective potential and the Higgs boson mass are investigated up to three-loop order. We found that, Higgs boson mass $m_{H}$ of one-loop order is large. The two-loop and three-loop results are not appreciably different from each other. The two-loop and three-loop radiative corrections have led to an improvement of Higgs boson mass and the value of the scalar coupling. For the value $m_{t}=170$ GeV at the energy scale $\\mu\\approx 5.68\\times10^2$GeV, we get $m_{H2-loop}\\approx 125.4$ GeV. At the energy scale $\\mu\\geq28\\times10^2$, the scalar coupling $\\lambda$ at two-loop becomes negative and leads to metastable vacuum while the three-loop level is stable even at high $\\mu$ $\\approx 10^{19}$ GeV. For the larger $\\mu$-range $(3 \\times 10^{3} \\text{GeV}\\leq \\mu \\leq 20 \\times 10^{3} \\text{GeV})$ spontaneous symmetry breaking for one-loop and three-loop occurs at approximately the same scalar couplin...
Influence of trapping potentials on the phase diagram of bosonic atoms in optical lattices
International Nuclear Information System (INIS)
We study the effect of external trapping potentials on the phase diagram of bosonic atoms in optical lattices. We introduce a generalized Bose-Hubbard Hamiltonian that includes the structure of the energy levels of the trapping potential, and show that these levels are in general populated both at finite and zero temperature. We characterize the properties of the superfluid transition for this situation and compare them with those of the standard Bose-Hubbard description. We briefly discuss similar behaviors for fermionic systems
Search for the Higgs Boson in the H→ ZZ(*)→4μ Channel in CMS Using a Multivariate Analysis
International Nuclear Information System (INIS)
This note presents a Higgs boson search analysis in the CMS detector of the LHC accelerator (CERN, Geneva, Switzerland) in the H→ ZZ(*)→4μ channel, using a multivariate method. This analysis, based in a Higgs boson mass dependent likelihood, constructed from discriminant variables, provides a significant improvement of the Higgs boson discovery potential in a wide mass range with respect to the official analysis published by CMS, based in orthogonal cuts independent of the Higgs boson mass. (Author) 8 refs
Vortex lattices for ultracold bosonic atoms in a non-Abelian gauge potential
Komineas, Stavros; Cooper, Nigel R.
2012-01-01
The use of coherent optical dressing of atomic levels allows the coupling of ultracold atoms to effective gauge fields. These can be used to generate effective magnetic fields, and have the potential to generate non-Abelian gauge fields. We consider a model of a gas of bosonic atoms coupled to a gauge field with U(2) symmetry, and with constant effective magnetic field. We include the effects of weak contact interactions by applying Gross-Pitaevskii mean-field theory. We study the effects of ...
Search of the Higgs boson decaying into tau-leptons at ATLAS
International Nuclear Information System (INIS)
The search for the Higgs boson is one of the main goals of the Large Hadron Collider experiments. Both in the Standard Model (SM) and in its minimal supersymmetric extensions (MSSM), one or several new bosons are expected as manifestations of the Higgs field. The tau lepton will be essential for Higgs(es) discovery. In fact, both in SM and in the MSSM, the Higgs boson(s) decaying into tau-pairs is one of the favourite discovery channels, especially at low masses. The discovery potential of the ATLAS experiment for neutral Higgs bosons decaying into tau-pairs is shown both in the SM and the MSSM. For the latter, the results on the charged Higgs boson decaying into tau lepton plus neutrino are also discussed.
Academic Training Lecture: Higgs Boson Searches at Hadron Colliders
HR Department
2010-01-01
Regular Programme 21, 22, 23 & 24 June 2010 from 11:00 to 12:00 - Main Auditorium, Bldg. 500-1-001 Higgs Boson Searches at Hadron Colliders by Dr. Karl Jakobs (University of Freiburg) In these Academic Training lectures, the phenomenology of Higgs bosons and search strategies at hadron colliders are discussed. After a brief introduction on Higgs bosons in the Standard Model and a discussion of present direct and indirect constraints on its mass the status of the theoretical cross section calculations for Higgs boson production at hadron colliders is reviewed. In the following lectures important experimental issues relevant for Higgs boson searches (trigger, measurements of leptons, jets and missing transverse energy) are presented. This is followed by a detailed discussion of the discovery potential for the Standard Model Higgs boson for both the Tevatron and the LHC experiments. In addition, various scenarios beyond the Standard Model, primarily the MSSM, are considered. Finally, the potential and ...
Sensitivity and Discovery Potential of the PROSPECT Experiment
,
2015-01-01
Measurements of the reactor antineutrino flux and spectrum compared to model predictions have revealed an apparent deficit in the interaction rates of reactor antineutrinos and an unexpected spectral deviation. PROSPECT, the Precision Reactor Oscillation Spectrum measurement, is designed to make a precision measurement of the antineutrino spectrum from a research reactor and search for signs of an eV-scale sterile neutrino. PROSPECT will be located at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory and make use of a Highly Enriched Uranium reactor for a measurement of the pure U-235 antineutrino spectrum. An absolute measurement of this spectrum will constrain reactor models and improve our understanding of the reactor antineutrino spectrum. Additionally, the planned 3-ton lithium-doped liquid scintillator detector is ideally suited to perform a search for sterile neutrinos. This talk will focus on the sensitivity and discovery potential of PROSPECT and the detector design to achieve the...
Three-Higgs-doublet models: symmetries, potentials and Higgs boson masses
Energy Technology Data Exchange (ETDEWEB)
Keus, Venus [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Department of Physics, Royal Holloway, University of London,Egham Hill, Egham TW20 0EX (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom); King, Stephen F. [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Moretti, Stefano [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom)
2014-01-13
We catalogue and study three-Higgs-doublet models in terms of all possible allowed symmetries (continuous and discrete, Abelian and non-Abelian), where such symmetries may be identified as flavour symmetries of quarks and leptons. We analyse the potential in each case, and derive the conditions under which the vacuum alignments (0,0,v), (0,v,v) and (v,v,v) are minima of the potential. For the alignment (0,0,v), relevant for dark matter models, we calculate the corresponding physical Higgs boson mass spectrum. Motivated by supersymmetry, we extend the analysis to the case of three up-type Higgs doublets and three down-type Higgs doublets (six doublets in total). Many of the results are also applicable to flavon models where the three Higgs doublets are replaced by three electroweak singlets.
A Jacobian generalization of the pseudo Nambu-Goldstone bosons potential
Hipólito-Ricaldi, W S
2015-01-01
We enlarge the classes of inflaton and quintessence fields by generalizing the pseudo Nambu-Goldstone boson potential by means of elliptic Jacobian functions characterized by a parameter $k$. We use such generalization to implement an inflationary era and a late acceleration of the universe. As an inflationary model the Jacobian generalization leads us to a number of e-foldings and a primordial spectrum of perturbations compatible with the Planck collaboration 2015. As a quintessence model, a study of the evolution of its Equation of State (EoS) and its $w'$-$w$ plane, helps us to classify it as a thawing model. This allows us to consider analytical approximations for the EoS recently discovered for thawing quintessence. By using Union 2.1 Supernova Ia and Hubble parameter $H(z)$ data we determine the range of $k$-values which give rise to viable models for the late acceleration of the universe.
Energy Technology Data Exchange (ETDEWEB)
Carena, M.; Heinemeyer, S.; Stål, O.; Wagner, C.E.M.; Weiglein, G.
2013-09-01
A Higgs-like particle with a mass of about 125.5 GeV has been discovered at the LHC. Within the current experimental uncertainties, this new state is compatible with both the predictions for the Standard Model (SM) Higgs boson and with the Higgs sector in the Minimal Supersymmetric Standard Model (MSSM). We propose new low-energy MSSM benchmark scenarios that, over a wide parameter range, are compatible with the mass and production rates of the observed signal. These scenarios also exhibit interesting phenomenology for the MSSM Higgs sector. We propose a slightly updated version of the well-known mh-max scenario, and a modified scenario (mh-mod), where the light CP-even Higgs boson can be interpreted as the LHC signal in large parts of the MA-tan \\beta\\ plane. Furthermore, we define a light stop scenario that leads to a suppression of the lightest CP-even Higgs gluon fusion rate, and a light stau scenario with an enhanced decay rate of h to \\gamma\\gamma\\ at large tan \\beta. We also suggest a \\tau-phobic Higgs scenario in which the lightest Higgs can have suppressed couplings to down-type fermions. We propose to supplement the specified value of the \\mu\\ parameter in some of these scenarios with additional values of both signs. This has a significant impact on the interpretation of searches for the non SM-like MSSM Higgs bosons. We also discuss the sensitivity of the searches to heavy Higgs decays into light charginos and neutralinos, and to decays of the form H to hh. Finally, in addition to all the other scenarios where the lightest CP-even Higgs is interpreted as the LHC signal, we propose a low-MH scenario, where instead the heavy CP-even Higgs boson corresponds to the new state around 125.5 GeV.
2014-01-01
Thursday, 12 June 2014 at 16:00 in the Library (52-1-052). The “Nobel Symposium on LHC results” took place at Krusenberg mansion, Uppsala, Sweden on 13-17 May 2013. The aim of the Symposium was to give an overview of the latest experimental and theoretical results pertaining to the LHC programme but also to give an occasion to ponder over the implications of these results in the broader context of the past, present and future evolution of the field of Particle Physics. “Nobel Symposium 154: The Higgs Boson Discovery and Other Recent LHC Results”, ed. by Tord Ekelöf, Physica Scripta T154, IOP, 2013, ISBN 9789789789781. * Coffee will be served from 15:30 * E-proceedings available here.
Energy Technology Data Exchange (ETDEWEB)
Carena, M. [Fermilab, Batavia, IL (United States). Theoretical Physics Dept.; Chicago Univ., IL (United States). Enrico Fermi Inst.; Chicago Univ., IL (United States). Kavli Inst. for Cosmological Physics; Heinemeyer, S. [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Staal, O. [Stockholm Univ. (Sweden). Dept. of Physics; Wagner, C.E.M. [Chicago Univ., IL (United States). Enrico Fermi Inst.; Chicago Univ., IL (United States). Kavli Inst. for Cosmological Physics; Argonne National Laboratory, Argonne, IL (United States). HEP Division; Weiglein, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2013-02-15
A Higgs-like particle with a mass of about 125.5 GeV has been discovered at the LHC. Within the current experimental uncertainties, this new state is compatible with both the predictions for the Standard Model (SM) Higgs boson and with the Higgs sector in the Minimal Supersymmetric Standard Model (MSSM). We propose new low- energy MSSM benchmark scenarios that, over a wide parameter range, are compatible with the mass and production rates of the observed signal. These scenarios also exhibit interesting phenomenology for the MSSM Higgs sector. We propose a slightly updated version of the well-known m{sup max}{sub h} scenario, and a modified scenario (m{sup mod}{sub h}), where the light CP-even Higgs boson can be interpreted as the LHC signal in large parts of the M{sub A}-tan {beta} plane. Furthermore, we define a light stop scenario that leads to a suppression of the lightest CP-even Higgs gluon fusion rate, and a light stau scenario with an enhanced decay rate of h{yields}{gamma}{gamma} at large tan {beta}. We also suggest a {tau}-phobic Higgs scenario in which the lightest Higgs can have suppressed couplings to down-type fermions. We propose to supplement the specified value of the {mu} parameter in some of these scenarios with additional values of both signs. This has a significant impact on the interpretation of searches for the non SM-like MSSM Higgs bosons. We also discuss the sensitivity of the searches to heavy Higgs decays into light charginos and neutralinos, and to decays of the form H{yields}{gamma}{gamma}. Finally, in addition to all the other scenarios where the lightest CP-even Higgs is interpreted as the LHC signal, we propose a low-M{sub H} scenario, where instead the heavy CP-even Higgs boson corresponds to the new state around 125.5 GeV.
Carena, M; Stål, O; Wagner, C E M; Weiglein, G
2013-01-01
A Higgs-like particle with a mass of about 125.5 GeV has been discovered at the LHC. Within the current experimental uncertainties, this new state is compatible with both the predictions for the Standard Model (SM) Higgs boson and with the Higgs sector in the Minimal Supersymmetric Standard Model (MSSM). We propose new low-energy MSSM benchmark scenarios that, over a wide parameter range, are compatible with the mass and production rates of the observed signal. These scenarios also exhibit interesting phenomenology for the MSSM Higgs sector. We propose a slightly updated version of the well-known mh-max scenario, and a modified scenario (mh-mod), where the light CP-even Higgs boson can be interpreted as the LHC signal in large parts of the MA-tan \\beta\\ plane. Furthermore, we define a light stop scenario that leads to a suppression of the lightest CP-even Higgs gluon fusion rate, and a light stau scenario with an enhanced decay rate of h to \\gamma\\gamma\\ at large tan \\beta. We also suggest a \\tau-phobic Higgs...
Symmetry-improved 2PI approach to the Goldstone-boson IR problem of the SM effective potential
Directory of Open Access Journals (Sweden)
Apostolos Pilaftsis
2016-05-01
Full Text Available The effective potential of the Standard Model (SM, from three loop order and higher, suffers from infrared (IR divergences arising from quantum effects due to massless would-be Goldstone bosons associated with the longitudinal polarizations of the W± and Z bosons. Such IR pathologies also hinder accurate evaluation of the two-loop threshold corrections to electroweak quantities, such as the vacuum expectation value of the Higgs field. However, these divergences are an artifact of perturbation theory, and therefore need to be consistently resummed in order to obtain an IR-safe effective potential. The so-called Two-Particle-Irreducible (2PI effective action provides a rigorous framework to consistently perform such resummations, without the need to resort to ad hoc subtractions or running into the risk of over-counting contributions. By considering the recently proposed symmetry-improved 2PI formalism, we address the problem of the Goldstone-boson IR divergences of the SM effective potential in the gaugeless limit of the theory. In the same limit, we evaluate the IR-safe symmetry-improved 2PI effective potential, after taking into account quantum loops of chiral fermions, as well as the renormalization of spurious custodially breaking effects triggered by fermionic Yukawa interactions. Finally, we compare our results with those obtained with other methods presented in the literature.
Symmetry-improved 2PI approach to the Goldstone-boson IR problem of the SM effective potential
Pilaftsis, Apostolos; Teresi, Daniele
2016-05-01
The effective potential of the Standard Model (SM), from three loop order and higher, suffers from infrared (IR) divergences arising from quantum effects due to massless would-be Goldstone bosons associated with the longitudinal polarizations of the W± and Z bosons. Such IR pathologies also hinder accurate evaluation of the two-loop threshold corrections to electroweak quantities, such as the vacuum expectation value of the Higgs field. However, these divergences are an artifact of perturbation theory, and therefore need to be consistently resummed in order to obtain an IR-safe effective potential. The so-called Two-Particle-Irreducible (2PI) effective action provides a rigorous framework to consistently perform such resummations, without the need to resort to ad hoc subtractions or running into the risk of over-counting contributions. By considering the recently proposed symmetry-improved 2PI formalism, we address the problem of the Goldstone-boson IR divergences of the SM effective potential in the gaugeless limit of the theory. In the same limit, we evaluate the IR-safe symmetry-improved 2PI effective potential, after taking into account quantum loops of chiral fermions, as well as the renormalization of spurious custodially breaking effects triggered by fermionic Yukawa interactions. Finally, we compare our results with those obtained with other methods presented in the literature.
Symmetry-Improved 2PI Approach to the Goldstone-Boson IR Problem of the SM Effective Potential
Pilaftsis, Apostolos
2015-01-01
The effective potential of the Standard Model (SM), from three loop order and higher, suffers from infra-red (IR) divergences arising from quantum effects due to massless would-be Goldstone bosons associated with the longitudinal polarizations of the W and Z bosons. Such IR pathologies also hinder accurate evaluation of the two-loop threshold corrections to electroweak quantities, such as the vacuum expectation value of the Higgs field. However, these divergences are an artifact of perturbation theory, and therefore need to be consistently resummed in order to obtain a IR-safe effective potential. The so-called Two-Particle-Irreducible (2PI) effective action provides a rigorous framework to consistently perform such resummations, without the need to resort to ad hoc subtractions or running into the risk of over-counting contributions. By considering the recently proposed symmetry-improved 2PI formalism, we address the problem of the Goldstone-boson IR divergences of the SM effective potential in the gaugeless...
International Nuclear Information System (INIS)
An evaluation of the discovery potential for NMSSM Higgs bosons of the ATLAS experiment at the LHC is presented. For this purpose, seven two-dimensional benchmark planes in the six-dimensional parameter space of the NMSSM Higgs sector are defined. These planes include different types of phenomenology for which the discovery of NMSSM Higgs bosons is especially challenging and which are considered typical for the NMSSM. They are subsequently used to give a detailed evaluation of the Higgs boson discovery potential based on Monte Carlo studies from the ATLAS collaboration. Afterwards, the possibility of discovering NMSSM Higgs bosons via the H1→A1A1→4τ→4μ+8ν decay chain and with the vector boson fusion production mode is investigated. A particular emphasis is put on the mass reconstruction from the complex final state. Furthermore, a study of the jet reconstruction performance at the ATLAS experiment which is of crucial relevance for vector boson fusion searches is presented. A good detectability of the so-called tagging jets that originate from the scattered partons in the vector boson fusion process is of critical importance for an early Higgs boson discovery in many models and also within the framework of the NMSSM. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Rottlaender, Iris
2008-08-15
An evaluation of the discovery potential for NMSSM Higgs bosons of the ATLAS experiment at the LHC is presented. For this purpose, seven two-dimensional benchmark planes in the six-dimensional parameter space of the NMSSM Higgs sector are defined. These planes include different types of phenomenology for which the discovery of NMSSM Higgs bosons is especially challenging and which are considered typical for the NMSSM. They are subsequently used to give a detailed evaluation of the Higgs boson discovery potential based on Monte Carlo studies from the ATLAS collaboration. Afterwards, the possibility of discovering NMSSM Higgs bosons via the H{sub 1}{yields}A{sub 1}A{sub 1}{yields}4{tau}{yields}4{mu}+8{nu} decay chain and with the vector boson fusion production mode is investigated. A particular emphasis is put on the mass reconstruction from the complex final state. Furthermore, a study of the jet reconstruction performance at the ATLAS experiment which is of crucial relevance for vector boson fusion searches is presented. A good detectability of the so-called tagging jets that originate from the scattered partons in the vector boson fusion process is of critical importance for an early Higgs boson discovery in many models and also within the framework of the NMSSM. (orig.)
SM Higgs boson searches in the early ATLAS data
Tsukerman, I
2010-01-01
ATLAS exclusion and discovery potentials of Standard Model Higgs boson searches at the LHC at 14 TeV, 10 TeV and 7 TeV center-of-mass energy are reviewed. For the total LHC energy of 7 TeV and the integrated luminosity of 1 $fb^{-1}$, contributions from important decay channels $H \\rightarrow WW^{*} \\rightarrow l\
Liew, T. C. H.; Glazov, M. M.; Kavokin, K. V.; Shelykh, I. A.; Kaliteevski, M A; Kavokin, A.V.
2012-01-01
We propose a concept of a quantum cascade laser based on transitions of bosonic quasiparticles (excitons and exciton-polaritons) in a parabolic potential trap in a semiconductor microcavity. This laser would emit terahertz radiation due to bosonic stimulation of excitonic transitions. Dynamics of a bosonic cascade is strongly different from the dynamics of a conventional fermionic cascade laser. We show that populations of excitonic ladders are parity-dependent and quantized if the laser oper...
International Nuclear Information System (INIS)
Experimentalists and theorists are still celebrating the Nobel-worthy discovery of the Higgs boson that was announced in July 2012 at CERN’s Large Hadron Collider. Now they are working on the profound implications of that discovery
Energy Technology Data Exchange (ETDEWEB)
Pangilinan, Monica [Brown Univ., Providence, RI (United States)
2010-05-01
The top quark produced through the electroweak channel provides a direct measurement of the V_{tb} element in the CKM matrix which can be viewed as a transition rate of a top quark to a bottom quark. This production channel of top quark is also sensitive to different theories beyond the Standard Model such as heavy charged gauged bosons termed W'. This thesis measures the cross section of the electroweak produced top quark using a technique based on using the matrix elements of the processes under consideration. The technique is applied to 2.3 fb^{-1} of data from the D0 detector. From a comparison of the matrix element discriminants between data and the signal and background model using Bayesian statistics, we measure the cross section of the top quark produced through the electroweak mechanism σ(p$\\bar{p}$ → tb + X, tqb + X) = 4.30_{-1.20}^{+0.98} pb. The measured result corresponds to a 4.9σ Gaussian-equivalent significance. By combining this analysis with other analyses based on the Bayesian Neural Network (BNN) and Boosted Decision Tree (BDT) method, the measured cross section is 3.94 ± 0.88 pb with a significance of 5.0σ, resulting in the discovery of electroweak produced top quarks. Using this measured cross section and constraining |V_{tb}| < 1, the 95% confidence level (C.L.) lower limit is |V_{tb}| > 0.78. Additionally, a search is made for the production of W' using the same samples from the electroweak produced top quark. An analysis based on the BDT method is used to separate the signal from expected backgrounds. No significant excess is found and 95% C.L. upper limits on the production cross section are set for W' with masses within 600-950 GeV. For four general models of W{prime} boson production using decay channel W' → t$\\bar{p}$, the lower mass limits are the following: M(W'_{L} with SM couplings) > 840 GeV; M(W'_{R}) > 880 GeV or 890 GeV if the
de Oliveira, L P
2015-01-01
The scattering of spin-1 bosons in a nonminimal vector double-step potential is described in terms of eigenstates of the helicity operator and it is shown that the transmission coefficient is insensitive to the choice of the polarization of the incident beam. Poles of the transmission amplitude reveal the existence of a two-fold degenerate spectrum. The results are interpreted in terms of solutions of two coupled effective Schr\\"{o}dinger equations for a finite square well with additional $\\delta $-functions situated at the borders.
Indian Academy of Sciences (India)
SATYAKI BHATTACHARYA; SHILPI JAIN
2016-09-01
In this review we have outlined a very brief history of the Higgs boson search and the development of the strategies for searching for the Higgs boson in its diphoton decay channel.We have reviewed the methodology and tools that led to the first observation of the Higgs boson decaying to a pair of photons. We have presented the latest results from the measured properties of the newly found boson.We concentrate for most part on the analysis developed by the CMS experiment, but also present the latest results of the ATLAS experiment along with CMS results.
Stefania Pandolfi
2016-01-01
CERN celebrated the fourth anniversary of the historical Higgs boson announcement with special pizzas. 400 pizzas were served on Higgs pizza day in Restaurant 1 at CERN to celebrate the fourth anniversary of the announcement of the discovery of the Higgs Boson (Image: Maximilien Brice/ CERN) What do the Higgs boson and a pizza have in common? Pierluigi Paolucci, INFN and CMS collaboration member, together with INFN president Fernando Ferroni found out the answer one day in Naples: the pizza in front of them looked exactly like a Higgs boson event display. A special recipe was then created in collaboration with the chef of the historic “Ettore” pizzeria in the St. Lucia area of Naples, and two pizzas were designed to resemble two Higgs boson decay channel event displays. The “Higgs Boson Pizza Day” was held on Monday, 4 July 2016, on the fourth anniversary of the announcement of the discovery of the Higgs boso...
Particle physics discovery potential using dark matter detectors
International Nuclear Information System (INIS)
Many of the present directions suggested for going ''beyond the Standard Model'' show promise for tests utilizing astrophysical sources. Some astrophysical puzzles suggest particle physics solutions requiring new, unconventional particles. In order to capitalize on these opportunities for progress in particle physics new detection techniques are required. Present technology has already permitted some important tests but the technology is near its limit. Intense activity is underway particularly in the area of cryogenic detectors. These developments have created an exciting new frontier at the intersection of condensed matter, astrophysics and particle physics. The nature of this frontier and its implications for progress in particle physics and its complementarity to the SSC potential are emphasized. Examples of dark matter and solar neutrino experiments are used to illustrate. 59 refs., 3 figs., 2 tabs
Kellerstein, M; Verbaarschot, J J M
2016-01-01
The behavior of quenched Dirac spectra of two-dimensional lattice QCD is consistent with spontaneous chiral symmetry breaking which is forbidden according to the Coleman-Mermin-Wagner theorem. One possible resolution of this paradox is that, because of the bosonic determinant in the partially quenched partition function, the conditions of this theorem are violated allowing for spontaneous symmetry breaking in two dimensions or less. This goes back to work by Niedermaier and Seiler on nonamenable symmetries of the hyperbolic spin chain and earlier work by two of the auhtors on bosonic partition functions at nonzero chemical potential. In this talk we discuss chiral symmetry breaking for the bosonic partition function of QCD at nonzero isospin chemical potential and a bosonic random matrix theory at imaginary chemical potential and compare the results with the fermionic counterpart. In both cases the chiral symmetry group of the bosonic partition function is noncompact.
Search for Higgs boson in beyond standard model scenarios at large hadron collider
Indian Academy of Sciences (India)
Kajari Mazumdar; on behalf of the ATLAS and CMS Collaborations
2007-11-01
The principal physics motivation of the LHC experiments is to search for the Higgs boson and to probe the physics of TeV energy scale. Potential of discovery for Higgs bosons in various scenarios beyond standard model have been estimated for both CMS and ATLAS experiments through detailed detector simulations. Main results from the recently published studies of CMS collaboration are only included in this write-up.
Charged Higgs boson searches and SemiConductor Tracker commissioning for the ATLAS experiment
Mohn, Bjarte Alsaker
2007-01-01
The ATLAS (A Toroidal Lhc ApparatuS) experiment is one of four major experiments presently being installed at the upcoming Large Hadron Collider (LHC) at the European Centre for Nuclear Research (CERN) outside Geneva. In this thesis we present work done on both the simulation of the ATLAS physics potential for a charged Higgs boson and the construction of the Semiconductor Tracker (SCT) - a subdetector within the ATLAS Inner Detector. The discovery of a charged Higgs boson w...
Higgs boson production at the LHC
Peters, Krisztian; The ATLAS collaboration
2015-01-01
After the discovery at the LHC, the main goal of the Higgs boson measurements at ATLAS and CMS is to fully elucidate the nature of this new particle. In this contribution we will discuss the Higgs boson production and decay properties at the LHC and the main analyses which build the fundation for the current Higgs boson property measurements. Inclusive rates as well as differential measurements in the main bosonic and fermionic channels, and searches for rarer decay modes will be presented.
Intrinsically Unstructured Proteins: Potential Targets for Drug Discovery
Directory of Open Access Journals (Sweden)
Pathan Salma
2009-01-01
Full Text Available Problem statement: The function of a protein is dependent on its three-dimensional structure. However, numerous proteins lacking intrinsic globular 3D structure under physiological conditions had been recognized. These proteins are frequently involved in some of the most critical cellular control mechanisms and it appears that their rapid turnover, aided by their unstructured nature in the unbound state, provides a level of control that allows rapid and accurate responses of the cell to changing environmental conditions. Approach: A significant number of proteins known to be involved in protein deposition disorders were now considered to Be Intrinsically Unstructured Proteins (IUPs. For example, Aß peptide and tau protein in Alzheimers disease, PrP in Prions disease and a-Synuclein in Parkinsons disease. The disorder of intrinsically unstructured proteins (IUP's was crucial to their functions. They may adopt defined but extended structures when bound to cognate ligands. Their amino acid compositions were less hydrophobic than those of soluble proteins. They lack hydrophobic cores and hence did not become insoluble when heated. About 40% of eukaryotic proteins had at least one long (>50 residues disordered region. Roughly 10% of proteins in various genomes had been predicted to be fully disordered. Presently over 100 IUP's had been identified; none are enzymes. Obviously, IUP's were greatly underrepresented in the Protein Data Bank, although there were few cases of an IUP bound to a folded (intrinsically structured protein. Results: The five functional categories for intrinsically unstructured proteins and domains were entropic chains (bristles to ensure spacing, springs, flexible spacers/linkers, effectors (inhibitors and disassemblers, scavengers, assemblers and display sites. These IUPs could serve as potential targets for Structure Based Drug Design (SBDD which stress on the transition
DEFF Research Database (Denmark)
Poulsen, Michael; Oh, Dong-Chan; Clardy, Jon;
2011-01-01
Identifying new sources for small molecule discovery is necessary to help mitigate the continuous emergence of antibiotic-resistance in pathogenic microbes. Recent studies indicate that one potentially rich source of novel natural products is Actinobacterial symbionts associated with social and...
Cinzia De Melis
2016-01-01
Four years after the historic announcement of the Higgs boson discovery at CERN, a collaboration between INFN and CERN has declared 4 July 2016 as “Higgs Boson Pizza Day”. The idea was born in Naples, by Pierluigi Paolucci and INFN president Fernando Ferroni, who inspired the chef of the historic “Ettore” pizzeria in St. Lucia to create the Higgs boson pizza in time for the opening of a Art&Science exhibition on 15 September 2015 in Naples. The animation shows the culinary creation of a Higgs boson in form of a vegetarian and ham&salami pizza. Ham&Salami: A two asparagus (proton-proton) collision produces a spicy Higgs boson (chorizo) decaying into two high-energy salami (photon) clusters and a lot of charged (sliced ham) and neutral (olive) particles that are detected in the pizza (detector) entirely covered with mozzarella sensors. A two asparagus (proton-proton) collision produces a juicy Higgs boson (cherry tomato) decaying into four high-energy (charged) peppers producing a tasty sign...
Hierarchy in Sampling Gaussian-correlated Bosons
Huh, Joonsuk
2016-01-01
Boson Sampling represents a class of physical processes potentially intractable for classical devices to simulate. The Gaussian extension of Boson Sampling remains a computationally hard problem, where the input state is a product of uncorrelated Gaussian modes. Besides, motivated by molecular spectroscopy, Vibronic Boson Sampling involves operations that can generate Gaussian correlation among different Boson modes. Therefore, Gaussian Boson Sampling is a special case of Vibronic Boson Sampling. However, this does not necessarily mean that Vibronic Boson Sampling is more complex than Gaussian Boson Sampling. Here we develop a hierarchical structure to show how the initial correlation in Vibronic Boson Sampling can be absorbed in Gaussian Boson Sampling with ancillary modes and in a scattershot fashion. Since every Gaussian state is associated with a thermal state, our result implies that every sampling problem in molecular vibronic transitions, at any temperature, can be simulated by Gaussian Boson Sampling ...
Rodríguez, Arturo
2016-01-01
The FCC project as well as the Pythia + Delphes analysis within the FCC software are introduced. The ROOT analysis carried out to reconstruct main observables, such the invariant mass of the bb system, transverse mass and momentum of the W boson together with the lepton pT and distribution is explained. The resulting reconstructed invariant mass of the bb system showed a peak near the 125 GeV in correspondence with the Higgs boson. Future steps towards estimating the physics potential of the FCC-hh machine in this channel are discussed.
Energy Technology Data Exchange (ETDEWEB)
Alonso Diaz, A.
2007-12-28
This note presents a Higgs boson search analysis in the CMS detector of the LHC accelerator (CERN, Geneva, Switzerland) in the H{yields} ZZ{sup (*)}{yields}4{mu} channel, using a multivariate method. This analysis, based in a Higgs boson mass dependent likelihood, constructed from discriminant variables, provides a significant improvement of the Higgs boson discovery potential in a wide mass range with respect to the official analysis published by CMS, based in orthogonal cuts independent of the Higgs boson mass. (Author) 8 refs.
Statistics of population difference for cold bosons in a double-well potential
International Nuclear Information System (INIS)
We study fluctuations in the atom number difference between halves of harmonically trapped Bose gas split by a delta potential. It is shown that the splitting potential affects fluctuations significantly. An analytical expression for the variance of atom number difference for the impenetrable potential barrier is given. Calculations are performed in the grand canonical ensemble. (paper)
International Nuclear Information System (INIS)
The vector couplings in the Duffin-Kemmer-Petiau (DKP) theory have been revised. It is shown that minimal and nonminimal vector potentials behave differently under charge-conjugation and time-reversal transformations. In particular, it is shown that nonminimal vector potentials have been erroneously applied to the description of elastic meson-nucleus scatterings and that the space component of the nonminimal vector potential plays a crucial role for the confinement of bosons. The DKP equation with nonminimal vector linear potentials is mapped into the nonrelativistic harmonic oscillator problem and the behavior of the solutions for this sort of DKP oscillator is discussed in detail. Furthermore, the absence of Klein's paradox and the localization of bosons in the presence of nonminimal vector interactions are discussed.
Discovering the Higgs boson with low mass muon pairs
International Nuclear Information System (INIS)
Many models of electroweak symmetry breaking have an additional light pseudoscalar. If the Higgs boson can decay to a new pseudoscalar, LEP searches for the Higgs can be significantly altered and the Higgs can be as light as 86 GeV. Discovering the Higgs boson in these models is challenging when the pseudoscalar is lighter than 10 GeV because it decays dominantly into tau leptons. In this paper, we discuss discovering the Higgs in a subdominant decay mode where one of the pseudoscalars decays to a pair of muons. This search allows for potential discovery of a cascade-decaying Higgs boson with the complete Tevatron data set or early data at the LHC.
Potential for optimizing Higgs boson CP measurement in H to tau tau decay at LHC and ML techniques
Józefowicz, R; Was, Z
2016-01-01
We investigate potential for measuring CP state of the Higgs boson in the H to tau tau$ decay with consecutive tau-lepton decays in channels: tau^+- to rho^+- nu_tau and tau^+- to a1^+- nu_tau combined. Subsequent decays rho^+- to pi^+- pi^0, a1^+- to rho^0 pi^+- and rho^0 to pi^+ pi^- are taken into account. We will explore extensions of the method, where acoplanarity angle for the planes build on the visible decay products, pi^+- pi^0 of tau^+- to pi^pm pi^0 nu_tau, was used. The angle is sensitive to transverse spin correlations, thus to parity. We show, that in the case of the cascade decays of tau to a1 nu, information on the CP state of Higgs can be extracted from the acoplanarity angles as well. Because in the cascade decay a1^+- to rho^0 pi^pm,rho^0 to pi^+ pi^- up to four planes can be defined, up to 16 distinct acoplanarity angles are available for H \\to tau tau to a1^+ a1^- nu nu decays. These acoplanarities carry in part supplementary but also correlated information. It is thus cumbersome to evalu...
Modified bosonic gas trapped in a generic 3-dim power law potential
Energy Technology Data Exchange (ETDEWEB)
Castellanos, E., E-mail: elias@zarm.uni-bremen.de; Laemmerzahl, C., E-mail: claus.laemmerzahl@zarm.uni-bremen.de
2014-04-04
We analyze the consequences caused by an anomalous single-particle dispersion relation suggested in several quantum-gravity models, upon the thermodynamics of a Bose–Einstein condensate trapped in a generic 3-dimensional power-law potential. We prove that the condensation temperature is shifted as a consequence of such deformation and show that this fact could be used to provide bounds on the deformation parameters. Additionally, we show that the shift in the condensation temperature, described as a non-trivial function of the number of particles and the trap parameters, could be used as a criterion to analyze the effects caused by a deformed dispersion relation in weakly interacting systems and also in finite size systems.
Modified bosonic gas trapped in a generic 3-dim power law potential
International Nuclear Information System (INIS)
We analyze the consequences caused by an anomalous single-particle dispersion relation suggested in several quantum-gravity models, upon the thermodynamics of a Bose–Einstein condensate trapped in a generic 3-dimensional power-law potential. We prove that the condensation temperature is shifted as a consequence of such deformation and show that this fact could be used to provide bounds on the deformation parameters. Additionally, we show that the shift in the condensation temperature, described as a non-trivial function of the number of particles and the trap parameters, could be used as a criterion to analyze the effects caused by a deformed dispersion relation in weakly interacting systems and also in finite size systems.
2014-01-01
The ATLAS & CMS Experiments Celebrate the 2nd Anniversary of the Discovery of the Higgs boson. Here, are some images of the path from LHC startup to Nobel Prize, featuring a musical composition by Roger Zare, performed by the Donald Sinta Quartet, called “LHC”. Happy Discovery Day!
International Nuclear Information System (INIS)
Introduction: Previously, development of novel brain radiotracers has largely relied on simple screening tools. Improved selection methods at the early stages of radiotracer discovery and an increased understanding of the relationships between in vitro physicochemical and in vivo radiotracer properties are needed. We investigated if high performance liquid chromatography (HPLC) methodologies could provide criteria for lead candidate selection by comparing HPLC measurements with radiotracer properties in humans. Methods: Ten molecules, previously used as radiotracers in humans, were analysed to obtain the following measures: partition coefficient (Log P); permeability (Pm); percentage of plasma protein binding (%PPB); and membrane partition coefficient (Km). Relationships between brain entry measurements (Log P, Pm and %PPB) and in vivo brain percentage injected dose (%ID); and Km and specific binding in vivo (BPND) were investigated. Log P values obtained using in silico packages and flask methods were compared with Log P values obtained using HPLC. Results: The modelled associations with %ID were stronger for %PPB (r2=0.65) and Pm (r2=0.77) than for Log P (r2=0.47) while 86% of BPND variance was explained by Km. Log P values were variable dependant on the methodology used. Conclusions: Log P should not be relied upon as a predictor of blood-brain barrier penetration during brain radiotracer discovery. HPLC measurements of permeability, %PPB and membrane interactions may be potentially useful in predicting in vivo performance and hence allow evaluation and ranking of compound libraries for the selection of lead radiotracer candidates at early stages of radiotracer discovery.
Higgs boson decays into single photon plus unparticle
International Nuclear Information System (INIS)
The decay of the standard model Higgs boson into a single photon and a vector unparticle through a one-loop process is studied. For an intermediate-mass Higgs boson, this single photon plus unparticle mode can have a branching ratio comparable with the two-photon discovery mode. The emitted photon has a continuous energy spectrum encoding the nature of the recoil unparticle. It can be measured in precision studies of the Higgs boson after its discovery.
Bosonic Coherent Motions in the Universe
Kim, Jihn E; Tsujikawa, Shinji
2014-01-01
We mini-review the role of fundamental spin-0 bosons as bosonic coherent motion (BCM) in the Universe. The fundamental spin-0 bosons have the potential to account for the baryon number generation, cold dark matter (CDM) via BCM, dark energy, and inflation. Among these, here we focus on the CDM possibility because it can be experimentally tested with the current experimental techniques. We also comment briefly on the panoply of the other roles of spin-0 bosons.
Rafehi, Haloom; Khan, Abdul Waheed; El-Osta, Assam
2016-04-01
Many epigenetic-based therapeutics, including drugs such as histone deacetylase inhibitors, are now used in the clinic or are undergoing advanced clinical trials. The study of chromatin-modifying proteins has benefited from the rapid advances in high-throughput sequencing methods, the organized efforts of major consortiums and by individual groups to profile human epigenomes in diverse tissues and cell types. However, while such initiatives have carefully characterized healthy human tissue, disease epigenomes and drug-epigenome interactions remain very poorly understood. Reviewed here is how high-throughput sequencing improves our understanding of chromatin regulator proteins and the potential implications for the study of human disease and drug development and discovery. PMID:26923902
CMS standard model Higgs boson results
Directory of Open Access Journals (Sweden)
Garcia-Abia Pablo
2013-11-01
Full Text Available In July 2012 CMS announced the discovery of a new boson with properties resembling those of the long-sought Higgs boson. The analysis of the proton-proton collision data recorded by the CMS detector at the LHC, corresponding to integrated luminosities of 5.1 fb−1 at √s = 7 TeV and 19.6 fb−1 at √s = 8 TeV, confirm the Higgs-like nature of the new boson, with a signal strength associated with vector bosons and fermions consistent with the expectations for a standard model (SM Higgs boson, and spin-parity clearly favouring the scalar nature of the new boson. In this note I review the updated results of the CMS experiment.
Directory of Open Access Journals (Sweden)
Michael Poulsen
Full Text Available Identifying new sources for small molecule discovery is necessary to help mitigate the continuous emergence of antibiotic-resistance in pathogenic microbes. Recent studies indicate that one potentially rich source of novel natural products is Actinobacterial symbionts associated with social and solitary Hymenoptera. Here we test this possibility by examining two species of solitary mud dauber wasps, Sceliphron caementarium and Chalybion californicum. We performed enrichment isolations from 33 wasps and obtained more than 200 isolates of Streptomyces Actinobacteria. Chemical analyses of 15 of these isolates identified 11 distinct and structurally diverse secondary metabolites, including a novel polyunsaturated and polyoxygenated macrocyclic lactam, which we name sceliphrolactam. By pairing the 15 Streptomyces strains against a collection of fungi and bacteria, we document their antifungal and antibacterial activity. The prevalence and anti-microbial properties of Actinobacteria associated with these two solitary wasp species suggest the potential role of these Streptomyces as antibiotic-producing symbionts, potentially helping defend their wasp hosts from pathogenic microbes. Finding phylogenetically diverse and chemically prolific Actinobacteria from solitary wasps suggests that insect-associated Actinobacteria can provide a valuable source of novel natural products of pharmaceutical interest.
Moss, Ian G
2015-01-01
The discovery of the Standard Model Higgs boson opens up a range of speculative cosmological scenarios, from the formation of structure in the early universe immediately after the big bang, to relics from the electroweak phase transition one nanosecond after the big bang, on to the end of the present-day universe through vacuum decay. Higgs physics is wide-ranging, and gives an impetus to go beyond the Standard Models of particle physics and cosmology to explore the physics of ultra-high energies and quantum gravity.
Baglio, Julien
2016-03-01
After the discovery of a Higgs boson in 2012 at the CERN Large Hadron Collider (LHC) the detailed study of its properties, and most importantly its couplings to other particles, has started. This is a very important task to be completed, in particular to test whether it is indeed the Higgs boson predicted by the Standard Model (SM). The precise study of the Higgs couplings to gauge bosons is of particular importance and requires as much information as possible. In this view this paper provides the next-to-leading order (NLO) QCD corrections to the production cross sections and differential distributions of a SM Higgs boson in association with a pair of weak bosons W+W- , W±Z and Z Z , matched with parton shower (PS) in the POWHEG-BOX framework. The NLO QCD corrections are found to be significant and PS effects are sizable at low pT in the jet differential distributions, as expected, while these effects are negligible in other distributions. We will also provide a detailed study of the theoretical uncertainties affecting the total production rates at the LHC and at the Future Circular Collider in hadron-hadron mode, the potential 100 TeV follow-up of the LHC machine: the scale uncertainty calculated by the variation of the renormalization and factorization scales, the parton distribution function and related αs errors as well as the parametric uncertainties on the input weak boson masses.
Recent developments in l-asparaginase discovery and its potential as anticancer agent.
Shrivastava, Abhinav; Khan, Abdul Arif; Khurshid, Mohsin; Kalam, Mohd Abul; Jain, Sudhir K; Singhal, Pradeep K
2016-04-01
l-Asparaginase (EC3.5.1.1) is an enzyme, which is used for treatment of acute lymphoblastic leukaemia (ALL) and other related blood cancers from a long time. This enzyme selectively hydrolyzes the extracellular amino acid l-asparagine into l-aspartate and ammonia, leading to nutritional deficiencies, protein synthesis inhibition, and ultimately death of lymphoblastic cells by apoptosis. Currently, bacterial asparaginases are used for treatment purpose but offers scepticism due to a number of toxicities, including thrombosis, pancreatitis, hyperglycemia, and hepatotoxicity. Resistance towards bacterial asparaginase is another major disadvantage during cancer management. This situation attracted attention of researchers towards alternative sources of l-asparaginase, including plants and fungi. Present article discusses about potential of l-asparaginase as an anticancer agent, its mechanism of action, and adverse effects related to current asparaginase formulations. This article also provides an outlook for recent developments in l-asparaginase discovery from alternative sources and their potential as a less toxic alternative to current formulations. PMID:25630663
Directory of Open Access Journals (Sweden)
Yuri Pevzner
2014-05-01
Full Text Available Inherent biological viability and diversity of natural products make them a potentially rich source for new therapeutics. However, identification of bioactive compounds with desired therapeutic effects and identification of their protein targets is a laborious, expensive process. Extracts from organism samples may show desired activity in phenotypic assays but specific bioactive compounds must be isolated through further separation methods and protein targets must be identified by more specific phenotypic and in vitro experimental assays. Still, questions remain as to whether all relevant protein targets for a compound have been identified. The desire is to understand breadth of purposing for the compound to maximize its use and intellectual property, and to avoid further development of compounds with insurmountable adverse effects. Previously we developed a Virtual Target Screening system that computationally screens one or more compounds against a collection of virtual protein structures. By scoring each compound-protein interaction, we can compare against averaged scores of synthetic drug-like compounds to determine if a particular protein would be a potential target of a compound of interest. Here we provide examples of natural products screened through our system as we assess advantages and shortcomings of our current system in regards to natural product drug discovery.
Cosmic gamma ray detection and discovery potential with the AMS-2 spectrometer
International Nuclear Information System (INIS)
Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release γ-ray studies, in the energy range from GeV to TeV, using the tracker system, for γ-rays converted in e+e- pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for γ-astrophysics is presented. While exposure maps of the γ--sky are computed for one year of data taking with the γ--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the Galactic Center. (author)
Development and exploration of potential routes of discovery of new superconductors
Energy Technology Data Exchange (ETDEWEB)
Lin, Xiao [Iowa State Univ., Ames, IA (United States)
2013-01-01
This thesis summarizes our efforts to develop and explore potential routes for the discovery of new superconductors. The development of viable solutions for sulfur-bearing compounds is presented. It also provides the details of searching for quantum critical points (QCPs) and possible superconductors by suppressing ferromagnetic states via chemical substitution and the application of pressure. The ferromagnetism in La(V_{x}Cr_{1-x})Ge_{3} was successfully suppressed by pressure, and, in addition, a potential QCP at ambient pressure was discovered for x = 0.16. On the other hand, the La(V_{x}Cr_{1-x})Sb_{3} series is likely to evolve into new magnetic state with V-substitution with the Cr-based magnetism appearing to be more local-moment like than for the case of LaCrGe_{3}. We also performed detailed characterization on BaSn_{5} superconductor, giving further understanding of its superconducting state, and on R_{3}Ni_{2-x}Sn_{7} and RNi_{1-x}Bi_{2±y }series putting to rest spurious claims of superconductivity.
Brunet, S
2014-01-01
ATLAS Higgs poster targeted to general public, explaining the Brout-Englert-Higgs mechanism and why it is important. It also explains the role of the Higgs Boson, how we look for it, the journey of the discovery and what comes after the discovery. Also available in French (http://cds.cern.ch/record/1697501). Don’t hesitate to use it in your institute’s corridors and in your outreach events! The poster is in A0 format. You can click on the image to download the high-quality .pdf version and print it at your favorite printshop. For any questions or comments you can contact atlas-outreach-coordination@cern.ch.
Bosonic interactions with a domain wall
Morris, J R
2016-01-01
We consider here the interaction of scalar bosons with a topological domain wall. Not only is there a continuum of scattering states, but there is also an interesting "quasi-discretuum" of positive energy bosonic bound states, describing bosons entrapped within the wall's core. The full spectrum of the scattering and bound state energies and eigenstates is obtainable from a Schr\\"odinger-type of equation with a P\\"oschl-Teller potential. We also consider the presence of a boson gas within the wall and high energy boson emission.
LHC Phenomenology of Z' and Z" bosons in the SU(4)_L \\times U(1)_X little Higgs model
Lee, Kang Young
2014-01-01
We examine direct limits on masses of the extra neutral gauge bosons in the SU(4)_L \\times U(1)_X model with a little Higgs mechanism confronted with the LHC data. There exist two extra neutral gauge bosons, calling Z' and Z", in this model. The lower exclusion limit of the mass of the lighter extra neutral gauge boson is about 3 TeV while that of the heavier one 5 TeV. For comparison, we examine the mass limit of Z'_3 boson in the SU(3)_L \\times U(1)_X model as well, and discuss the implication of our result in the SU(4)_L \\times U(1)_X model with a standard Higgs mechanism. We also discuss the discovery potential of Z' and Z" at the future LHC with the center-of-momentum energy of 14 TeV.
New constraints and discovery potential for Higgs to Higgs cascade decays through vectorlike leptons
Dermisek, Radovan; Shin, Seodong
2016-01-01
One of the cleanest signatures of a heavy Higgs boson in models with vectorlike leptons is $H\\to e_4^\\pm \\ell^\\mp \\to h\\ell^+\\ell^-$ which, in two Higgs doublet model type-II, can even be the dominant decay mode of heavy Higgses. Among the decay modes of the standard model like Higgs boson, $h$, we consider $b \\bar b$ and $\\gamma \\gamma$ as representative channels with sizable and negligible background, respectively. We obtained new model independent limits on production cross section for this process from recasting existing experimental searches and interpret them within the two Higgs doublet model. In addition, we show that these limits can be improved by about two orders of magnitude with appropriate selection cuts immediately with existing data sets. We also discuss expected sensitivities with integrated luminosity up to 3 ab$^{-1}$ and present a brief overview of other channels.
International Nuclear Information System (INIS)
The CMS (compact muon solenoid) detector that will be set on the future LHC (large hadron collider) accelerator will enable us to continue our search for the Higgs boson as well as to look for any hint for a new physics beyond the standard model. CMS is composed of an efficient muon detector, an electromagnetic calorimeter and of a tracker with high spatial resolution, this tracker is the topic of this thesis. The tracker will allow an accurate reconstruction of charged-particles trajectories and the reconstruction of the primary interaction vertex. The tracker's technology is based on micro-strip Si detectors, tests performed with the SPS particle beam show that these detectors have an impact reconstruction efficiency greater than 98% and a piling-up rate limited to 6%. The spatial resolution concerning particle trajectories is about 45 μm for an interval of 183 μm between 2 strips. The simulation for the search for a light charged Higgs boson show that an excess of τντ + bb-bar + qq-bar' events is possible to be observed for any value of tan(β) up to MA = 122 GeV/c2 during the first year of operation and up to 136 GeV/c2 afterwards. With the assumption that this event excess is due to the decay of charged Higgs bosons we can state that the assessment of its mass will be possible till mH = 150 GeV/c2 with an accuracy of 15 GeV/c2. (A.C.)
Interference of composite bosons
Brougham, Thomas; Barnett, Stephen M.; Jex, Igor
2010-01-01
We investigate multi-boson interference. A Hamiltonian is presented that treats pairs of bosons as a single composite boson. This Hamiltonian allows two pairs of bosons to interact as if they were two single composite bosons. We show that this leads to the composite bosons exhibiting novel interference effects such as Hong-Ou-Mandel interference. We then investigate generalizations of the formalism to the case of interference between two general composite bosons. Finally, we show how one can ...
Sparticle Discovery Potentials in the CMSSM and GUT-less Supersymmetry-Breaking Scenarios
Ellis, Jonathan Richard; Sandick, Pearl
2008-01-01
We consider the potentials of the LHC and a linear e^+e^- collider (LC) for discovering supersymmetric particles in variants of the MSSM with soft supersymmetry-breaking mass parameters constrained to be universal at the GUT scale (CMSSM) or at some lower scale M_{in} (GUT-less models), as may occur in some scenarios with mirage unification. Whereas the LHC should be able to discover squarks and/or gluinos along all the CMSSM coannihilation strip where the relic neutralino LSP density lies within the range favoured for cold dark matter, many GUT-less models could escape LHC detection. In particular, if M_{in} < 10^{11} GeV, the LHC would not detect sparticles if the relic density lies within the favoured range. For any given discovery of supersymmetry at the LHC, in such GUT-less models the lightest neutralino mass and hence the threshold for sparticle pair production at a LC increases as M_{in} decreases, and the CMSSM offers the best prospects for measuring sparticles at a LC. For example, if the LHC dis...
The ATLAS discovery potential for a charged slepton as next-to-lightest supersymmetric particle
International Nuclear Information System (INIS)
Supersymmetric models with conserved R-parity require the lightest supersymmetric particle (LSP) to be stable. This means that, if neutral, the LSP may provide a good candidate for (cold) dark matter (DM). The most popular LSP candidate is the lightest neutralino, a particle already present in minimal supersymmetric extension of the Standard Model (MSSM). However, new possibilities arise if one considers particles which are not part of the MSSM such as the axino, the spin-1/2 superpartner of the axion, and the gravitino, the spin-3/2 superpartner of the graviton. Both the axino and the gravitino allow a long-lived charged slepton to be the next-to-lightest SUSY particle (NLSP): the stau τ, i.e. the superpartner of the tau lepton. Being also weakly-interacting and penetrating, the stau will escape the hadronic calorimeters of the ATLAS detector and will appear as a track in the muon system. It will therefore look like and reconstructed as a slow-moving massive muon. A direct consequence of R-parity conservation is that we expect exactly two of such tracks per event. The discovery potential of the ATLAS detector is investigated for different values of the parameters of the SUSY model
Deep-sea hydrothermal vents: potential hot spots for natural products discovery?
Thornburg, Christopher C; Zabriskie, T Mark; McPhail, Kerry L
2010-03-26
Deep-sea hydrothermal vents are among the most extreme and dynamic environments on Earth. However, islands of highly dense and biologically diverse communities exist in the immediate vicinity of hydrothermal vent flows, in stark contrast to the surrounding bare seafloor. These communities comprise organisms with distinct metabolisms based on chemosynthesis and growth rates comparable to those from shallow water tropical environments, which have been rich sources of biologically active natural products. The geological setting and geochemical nature of deep-sea vents that impact the biogeography of vent organisms, chemosynthesis, and the known biological and metabolic diversity of Eukarya, Bacteria, and Archaea, including the handful of natural products isolated to date from deep-sea vent organisms, are considered here in an assessment of deep-sea hydrothermal vents as potential hot spots for natural products investigations. Of critical importance too are the logistics of collecting deep vent organisms, opportunities for re-collection considering the stability and longevity of vent sites, and the ability to culture natural product-producing deep vent organisms in the laboratory. New cost-effective technologies in deep-sea research and more advanced molecular techniques aimed at screening a more inclusive genetic assembly are poised to accelerate natural product discoveries from these microbial diversity hot spots. PMID:20099811
Directory of Open Access Journals (Sweden)
Dey Dipak K
2008-01-01
Full Text Available Abstract Background The discovery of biomarkers is an important step towards the development of criteria for early diagnosis of disease status. Recently electrospray ionization (ESI and matrix assisted laser desorption (MALDI time-of-flight (TOF mass spectrometry have been used to identify biomarkers both in proteomics and metabonomics studies. Data sets generated from such studies are generally very large in size and thus require the use of sophisticated statistical techniques to glean useful information. Most recent attempts to process these types of data model each compound's intensity either discretely by positional (mass to charge ratio clustering or through each compounds' own intensity distribution. Traditionally data processing steps such as noise removal, background elimination and m/z alignment, are generally carried out separately resulting in unsatisfactory propagation of signals in the final model. Results In the present study a novel semi-parametric approach has been developed to distinguish urinary metabolic profiles in a group of traumatic patients from those of a control group consisting of normal individuals. Data sets obtained from the replicates of a single subject were used to develop a functional profile through Dirichlet mixture of beta distribution. This functional profile is flexible enough to accommodate variability of the instrument and the inherent variability of each individual, thus simultaneously addressing different sources of systematic error. To address instrument variability, all data sets were analyzed in replicate, an important issue ignored by most studies in the past. Different model comparisons were performed to select the best model for each subject. The m/z values in the window of the irregular pattern are then further recommended for possible biomarker discovery. Conclusion To the best of our knowledge this is the very first attempt to model the physical process behind the time-of flight mass
International Nuclear Information System (INIS)
The 4 of July 2012, the CERN physicists announced the discovery of the Higgs boson, a particle which existence is essential to the understanding of our world. The paper relates this day which will remain in the history of the physics of particles, and gives some details of the results of the CMS and Atlas experiments on the CERN Large Hadron Collider (LHC). Results from the Fermilab's Tevatron accelerator are also mentioned
Cotner, Eric
2016-01-01
Scalar particles are a common prediction of many beyond the Standard Model theories. If they are light and cold enough, there is a possibility they may form Bose-Einstein condensates, which will then become gravitationally bound. These boson stars are solitonic solutions to the Einstein-Klein-Gordon equations, but may be approximated in the non-relativistic regime with a coupled Schr\\"odinger-Poisson system. General properties of single soliton states are derived, including the possibility of quartic self-interactions. Binary collisions between two solitons are then studied, and the effects of different mass ratios, relative phases, self-couplings, and separation distances are characterized, leading to an easy conceptual understanding of how these parameters affect the collision outcome in terms of conservation of energy. Applications to dark matter are discussed.
Reconstruction of Higgs bosons in the di-tau channel via 3-prong decay
Gripaios, Ben; Nojiri, Mihoko; Sakurai, Kazuki; Webber, Bryan
2012-01-01
We propose a method for reconstructing the mass of a particle, such as the Higgs boson, decaying into a pair of tau leptons, of which one subsequently undergoes a 3-prong decay. The kinematics is solved using information from the visible decay products, the missing transverse momentum, and the 3-prong tau decay vertex, with the detector resolution taken into account using a likelihood method. The method is shown to give good discrimination between a 125 GeV Higgs boson signal and the dominant backgrounds, such as Z decays to tau tau and W plus jets production. As a result, we find an improvement, compared to existing methods for this channel, in the discovery potential, as well as in measurements of the Higgs boson mass and production cross section times branching ratio.
Reconstruction of Higgs bosons in the di-tau channel via 3-prong decay
Energy Technology Data Exchange (ETDEWEB)
Gripaios, Ben; Webber, Bryan [Cambridge Univ. (United Kingdom). Cavendish Lab.; Nagao, Keiko [KEK Theory Center, Tsukuba (Japan); Nojiri, Mihoko [KEK Theory Center, Tsukuba (Japan); The Graduate Univ. for Advanced Studies (Sokendai) IPNS, KEK, Tsukuba (Japan); Kavli Institute of the Physics and Mathematics of the Universe (Kavli IPMU), Chiba (Japan); Sakurai, Kazuki [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2012-10-15
We propose a method for reconstructing the mass of a particle, such as the Higgs boson, decaying into a pair of {tau} leptons, of which one subsequently undergoes a 3-prong decay. The kinematics is solved using information from the visible decay products, the missing transverse momentum, and the 3-prong {tau} decay vertex, with the detector resolution taken into account using a likelihood method. The method is shown to give good discrimination between a 125 GeV Higgs boson signal and the dominant backgrounds, such as Z{sup 0} decays to {tau}{tau} and W{sup {+-}} plus jets production. As a result, we find an improvement, compared to existing methods for this channel, in the discovery potential, as well as in measurements of the Higgs boson mass and production cross section times branching ratio.
DEFF Research Database (Denmark)
Tichy, Malte C.; Bouvrier, P. Alexander; Mølmer, Klaus
2013-01-01
Composite bosons made of two bosonic constituents exhibit deviations from ideal bosonic behavior due to their substructure. This deviation is reflected by the normalization ratio of the quantum state of N composites. We find a set of saturable, efficiently evaluable bounds for this indicator, which...... quantifies the bosonic behavior of composites via the entanglement of their constituents. We predict an abrupt transition between ordinary and exaggerated bosonic behavior in a condensate of two-boson composites....
Charged Higgs boson searches and SemiConductor Tracker commissioning for the ATLAS experiment
Mohn, Bjarte Alsaker
The ATLAS (A Toroidal Lhc ApparatuS) experiment is one of four major experiments presently being installed at the upcoming Large Hadron Collider (LHC) at the European Centre for Nuclear Research (CERN) outside Geneva. In this thesis we present work done on both the simulation of the ATLAS physics potential for a charged Higgs boson and the construction of the Semiconductor Tracker (SCT) - a subdetector within the ATLAS Inner Detector. The discovery of a charged Higgs boson would be an unambiguous sign of physics beyond the Standard Model (SM) and it is thus of great interest to study the ATLAS potential for a charged Higgs discovery. Two such studies have been conducted for this thesis. In the first study a large-mass-splitting Minimal Supersymmetric Standard Model (MSSM) is assumed in which the charged Higgs boson decays into a W boson and a neutral Higgs may receive a large branching ratio.We conclude, however, that charged Higgs searches in this decay channel are made difficult by a large irreducible SM ba...
Potential of knowledge discovery using workflows implemented in the C3Grid
Engel, Thomas; Fink, Andreas; Ulbrich, Uwe; Schartner, Thomas; Dobler, Andreas; Fritzsch, Bernadette; Hiller, Wolfgang; Bräuer, Benny
2013-04-01
alteration of surface cyclones. A specific feature of C3Grid is the flexible Workflow Scheduling Service (WSS) which also allows for automated nightly analysis runs of CT, Stormtrack, etc. with different input parameter sets. The statistical results of these workflows can be accumulated afterwards by a scheduled final analysis step, thereby providing a tool for data intensive analytics for the massive amounts of climate model data accessible through C3Grid. First tests with these automated analysis workflows show promising results to speed up the investigation of high volume modeling data. This example is relevant to the thorough analysis of future changes in storminess in Europe and is just one example of the potential of knowledge discovery using automated workflows implemented in the C3Grid architecture.
Wells, James D
2015-01-01
With the Higgs boson discovery and no new physics found at the LHC, confidence in Naturalness as a guiding principle for particle physics is under increased pressure. We wait to see if it proves its mettle in the LHC upgrades ahead, and beyond. In the meantime, in a series of "realistic intellectual leaps" I present a justification {\\it a posteriori} of the Naturalness criterion by suggesting that uncompromising application of the principle to quantum electrodynamics leads toward the Standard Model and Higgs boson without additional experimental input. Potential lessons for today and future theory building are commented upon.
Directory of Open Access Journals (Sweden)
Samuel Arbesman
Full Text Available BACKGROUND: The search for a habitable extrasolar planet has long interested scientists, but only recently have the tools become available to search for such planets. In the past decades, the number of known extrasolar planets has ballooned into the hundreds, and with it, the expectation that the discovery of the first Earth-like extrasolar planet is not far off. METHODOLOGY/PRINCIPAL FINDINGS: Here, we develop a novel metric of habitability for discovered planets and use this to arrive at a prediction for when the first habitable planet will be discovered. Using a bootstrap analysis of currently discovered exoplanets, we predict the discovery of the first Earth-like planet to be announced in the first half of 2011, with the likeliest date being early May 2011. CONCLUSIONS/SIGNIFICANCE: Our predictions, using only the properties of previously discovered exoplanets, accord well with external estimates for the discovery of the first potentially habitable extrasolar planet and highlight the the usefulness of predictive scientometric techniques to understand the pace of scientific discovery in many fields.
INSECTS AND THEIR CHEMICAL WEAPONRY: GREAT POTENTIAL AND NEW DISCOVERIES FROM THE ORDER PHASMATODEA
With over 1,000,000 species of insects known, Class Insecta (Phyllum Arthropoda), the largest and most diverse group of organisms, is one of the least explored in natural product drug discovery (Dossey, A. T., Nat. Prod Rep. 2010, 27, 1737–1757). Over the past five our research stick insect chemical...
Identification of extra neutral gauge bosons at the International Linear Collider
Osland, P; Tsytrinov, A V
2009-01-01
Heavy neutral gauge bosons, Z's, are predicted by many theoretical schemes of physics beyond the Standard Model, and intensive searches for their signatures will be performed at present and future high energy colliders. It is quite possible that Z's are heavy enough to lie beyond the discovery reach expected at the CERN Large Hadron Collider LHC, in which case only indirect signatures of Z' exchanges may occur at future colliders, through deviations of the measured cross sections from the Standard Model predictions. We here discuss in this context the foreseeable sensitivity to Z's of fermion-pair production cross sections at an e^+e^- linear collider, especially as regards the potential of distinguishing different Z' models once such deviations are observed. Specifically, we assess the discovery and identification reaches on Z' gauge bosons pertinent to the E_6, LR, ALR and SSM classes of models, that should be attained at the planned International Linear Collider (ILC). With the high experimental accuracies...
International Nuclear Information System (INIS)
The discovery of the Z boson 7 years ago verified a key prediction of the unified theory of electromagnetic and weak forces. Today an experimental program is beginning at two electron-positron colliders to study the properties of the Z particle in great detail. The data accumulated will subject the unified theory to more rigorous tests and will probe with great sensitivity for new physics not encompassed by the existing standard model of the elementary particles and forces. Questions under study include the number of quark and lepton families, the mass of the still undiscovered top quark, and the search for the still unknown fifth force of nature required by the theory to generate the masses of the elementary particles. 48 refs., 3 figs., 1 tab
Evidence of Higgs Boson Production through Vector Boson Fusion
AUTHOR|(INSPIRE)INSPIRE-00333580
The discovery of the Higgs boson in 2012 provided confirmation of the proposed mechanism for preserving the electroweak $SU(2) \\times U(1)$ gauge symmetry of the Standard Model of particle physics. It also heralded in a new era of precision Higgs physics. This thesis presents a measurement of the rate at which the Higgs boson is produced by vector boson fusion in the \\wwlnln decay channel. With gauge boson couplings in both the production and decay vertices, a VBF measurement in this channel is a powerful probe of the $VVH$ vertex strength. Using $4.5$~fb$^{-1}$ and $20.3$~fb$^{-1}$ of $pp$ collision data collected at respective center-of-mass energies of 7 and $8 \\tev$ in the ATLAS detector, measurements of the statistical significance and the signal strength are carried out in the Higgs mass range $100 \\leq m_H \\leq 200 \\gev$. These measurements are enhanced with a boosted decision tree that exploits the correlations between eight kinematic inputs in order to separate signal and background processes. At the...
Cracking the particle code of the universe the hunt for the Higgs boson
Moffat, John W
2014-01-01
Among the current books that celebrate the discovery of the Higgs boson, Cracking the Particle Code of the Universe is a rare objective treatment of the subject. The book is an insider's behind-the-scenes look at the arcane, fascinating world of theoretical and experimental particle physics leading up to the recent discovery of a new boson. If the new boson is indeed the Higgs particle, its discovery represents an important milestone in the history of particle physics. However, despite the pressure to award Nobel Prizes to physicists associated with the Higgs boson, John Moffat argues that the
Acquiring a taste for the Higgs boson
Caroline Duc
2012-01-01
Before CERN's scientists had even announced the discovery of the Higgs boson, others were already attributing some interesting characteristics to it: flavoursome, sparkling and liquid... The artisan brewery Hopfenstark in Quebec launched its new "Higgs boson" beer in November 2010. Ever since, it has been intriguing enthusiasts with its unique taste explosion. The boson was a source of inspiration for brewer Frédéric Cormier, the Hopfenstark brewery's owner, who is a big fan of science programmes. "I returned from a trip to Europe in 2010 with the idea for a new beer that would be unlike any other," he explains. "I was always reading and hearing about CERN's particle accelerator in the media, so I did some research on the famous Higgs boson and decided to give my new creation the same name." For Frédéric Cormier, it's important that the names of his beers refle...
International Nuclear Information System (INIS)
A focused strategy has been directed towards the structural characterization of selected proteins from the bacterial pathogen P. aeruginosa. The objective is to exploit the resulting structural data, in combination with ligand-binding studies, and to assess the potential of these proteins for early-stage antimicrobial drug discovery. Bacterial infections are increasingly difficult to treat owing to the spread of antibiotic resistance. A major concern is Gram-negative bacteria, for which the discovery of new antimicrobial drugs has been particularly scarce. In an effort to accelerate early steps in drug discovery, the EU-funded AEROPATH project aims to identify novel targets in the opportunistic pathogen Pseudomonas aeruginosa by applying a multidisciplinary approach encompassing target validation, structural characterization, assay development and hit identification from small-molecule libraries. Here, the strategies used for target selection are described and progress in protein production and structure analysis is reported. Of the 102 selected targets, 84 could be produced in soluble form and the de novo structures of 39 proteins have been determined. The crystal structures of eight of these targets, ranging from hypothetical unknown proteins to metabolic enzymes from different functional classes (PA1645, PA1648, PA2169, PA3770, PA4098, PA4485, PA4992 and PA5259), are reported here. The structural information is expected to provide a firm basis for the improvement of hit compounds identified from fragment-based and high-throughput screening campaigns
International Nuclear Information System (INIS)
We investigate the discovery potential of the LHC experiments for R-parity violating supersymmetric models with a stau as the lightest supersymmetric particle (LSP) in the framework of minimal supergravity. We classify the final states according to their phenomenology for different R-parity violating decays of the LSP. We then develop event selection cuts for a specific benchmark scenario with promising signatures for the first beyond the standard model discoveries at the LHC. For the first time in this model, we perform a detailed signal over background analysis. We use fast detector simulations to estimate the discovery significance taking the most important standard model backgrounds into account. Assuming an integrated luminosity of 1 fb-1 at a center-of-mass energy of √(s)=7 TeV, we perform scans in the parameter space around the benchmark scenario we consider. We then study the feasibility to estimate the mass of the stau LSP. We briefly discuss difficulties, which arise in the identification of hadronic tau decays due to small tau momenta and large particle multiplicities in our scenarios.
Open Innovation Drug Discovery (OIDD): a potential path to novel therapeutic chemical space.
Alvim-Gaston, Maria; Grese, Timothy; Mahoui, Abdelaziz; Palkowitz, Alan D; Pineiro-Nunez, Marta; Watson, Ian
2014-01-01
The continued development of computational and synthetic methods has enabled the enumeration or preparation of a nearly endless universe of chemical structures. Nevertheless, the ability of this chemical universe to deliver small molecules that can both modulate biological targets and have drug-like physicochemical properties continues to be a topic of interest to the pharmaceutical industry and academic researchers alike. The chemical space described by public, commercial, in-house and virtual compound collections has been interrogated by multiple approaches including biochemical, cellular and virtual screening, diversity analysis, and in-silico profiling. However, current drugs and known chemical probes derived from these efforts are contained within a remarkably small volume of the predicted chemical space. Access to more diverse classes of chemical scaffolds that maintain the properties relevant for drug discovery is certainly needed to meet the increasing demands for pharmaceutical innovation. The Lilly Open Innovation Drug Discovery platform (OIDD) was designed to tackle barriers to innovation through the identification of novel molecules active in relevant disease biology models. In this article we will discuss several computational approaches towards describing novel, biologically active, drug-like chemical space and illustrate how the OIDD program may facilitate access to previously untapped molecules that may aid in the search for innovative pharmaceuticals. PMID:24283973
Potential Approaches and Recent Advances in Biomarker Discovery in Clear-Cell Renal Cell Carcinoma
Majer, Weronika; Kluzek, Katarzyna; Bluyssen, Hans; Wesoły, Joanna
2015-01-01
The early diagnosis and monitoring of clear-cell Renal Cell Carcinoma (ccRCC), which is the most common renal malignancy, remains challenging. The late diagnosis and lack of tools that can be used to assess the progression of the disease and metastasis significantly influence the chance of survival of ccRCC patients. Molecular biomarkers have been shown to aid the diagnosis and disease monitoring for other cancers, but such markers are not currently available for ccRCC. Recently, plasma and serum circulating nucleic acids, nucleic acids present in urine, and plasma and urine proteins gained interest in the field of cancer biomarker discovery. Here, we describe the applicability of plasma and urine nucleic acids as cancer biomarkers with a particular focus on DNA, small RNA, and protein markers for ccRCC. PMID:26516358
Energy Technology Data Exchange (ETDEWEB)
Hartmann, Betti [School of Engineering and Science, Jacobs University, Postfach 750 561, D-28725 Bremen (Germany); Kleihaus, Burkhard; Kunz, Jutta [Institut fuer Physik, Universitaet Oldenburg, Postfach 2503, D-26111 Oldenburg (Germany); Schaffer, Isabell, E-mail: i.schaffer@jacobs-university.de [School of Engineering and Science, Jacobs University, Postfach 750 561, D-28725 Bremen (Germany)
2012-07-24
We consider compact boson stars that arise for a V-shaped scalar field potential. They represent a one parameter family of solutions of the scaled Einstein-Gordon equations. We analyze the physical properties of these solutions and determine their domain of existence. Along their physically relevant branch emerging from the compact Q-ball solution, their mass increases with increasing radius. Employing arguments from catastrophe theory we argue that this branch is stable, until the maximal value of the mass is reached. There the mass and size are on the order of magnitude of the Schwarzschild limit, and thus the spiraling respectively oscillating behaviour, well known for compact stars, sets in.
Sharma, Charu; Sadek, Bassem; Goyal, Sameer N; Sinha, Satyesh; Kamal, Mohammad Amjad; Ojha, Shreesh
2015-01-01
The cannabinoid molecules are derived from Cannabis sativa plant which acts on the cannabinoid receptors types 1 and 2 (CB1 and CB2) which have been explored as potential therapeutic targets for drug discovery and development. Currently, there are numerous cannabinoid based synthetic drugs used in clinical practice like the popular ones such as nabilone, dronabinol, and Δ(9)-tetrahydrocannabinol mediates its action through CB1/CB2 receptors. However, these synthetic based Cannabis derived compounds are known to exert adverse psychiatric effect and have also been exploited for drug abuse. This encourages us to find out an alternative and safe drug with the least psychiatric adverse effects. In recent years, many phytocannabinoids have been isolated from plants other than Cannabis. Several studies have shown that these phytocannabinoids show affinity, potency, selectivity, and efficacy towards cannabinoid receptors and inhibit endocannabinoid metabolizing enzymes, thus reducing hyperactivity of endocannabinoid systems. Also, these naturally derived molecules possess the least adverse effects opposed to the synthetically derived cannabinoids. Therefore, the plant based cannabinoid molecules proved to be promising and emerging therapeutic alternative. The present review provides an overview of therapeutic potential of ligands and plants modulating cannabinoid receptors that may be of interest to pharmaceutical industry in search of new and safer drug discovery and development for future therapeutics. PMID:26664449
Directory of Open Access Journals (Sweden)
Charu Sharma
2015-01-01
Full Text Available The cannabinoid molecules are derived from Cannabis sativa plant which acts on the cannabinoid receptors types 1 and 2 (CB1 and CB2 which have been explored as potential therapeutic targets for drug discovery and development. Currently, there are numerous cannabinoid based synthetic drugs used in clinical practice like the popular ones such as nabilone, dronabinol, and Δ9-tetrahydrocannabinol mediates its action through CB1/CB2 receptors. However, these synthetic based Cannabis derived compounds are known to exert adverse psychiatric effect and have also been exploited for drug abuse. This encourages us to find out an alternative and safe drug with the least psychiatric adverse effects. In recent years, many phytocannabinoids have been isolated from plants other than Cannabis. Several studies have shown that these phytocannabinoids show affinity, potency, selectivity, and efficacy towards cannabinoid receptors and inhibit endocannabinoid metabolizing enzymes, thus reducing hyperactivity of endocannabinoid systems. Also, these naturally derived molecules possess the least adverse effects opposed to the synthetically derived cannabinoids. Therefore, the plant based cannabinoid molecules proved to be promising and emerging therapeutic alternative. The present review provides an overview of therapeutic potential of ligands and plants modulating cannabinoid receptors that may be of interest to pharmaceutical industry in search of new and safer drug discovery and development for future therapeutics.
Sharma, Charu; Sadek, Bassem; Goyal, Sameer N.; Sinha, Satyesh; Ojha, Shreesh
2015-01-01
The cannabinoid molecules are derived from Cannabis sativa plant which acts on the cannabinoid receptors types 1 and 2 (CB1 and CB2) which have been explored as potential therapeutic targets for drug discovery and development. Currently, there are numerous cannabinoid based synthetic drugs used in clinical practice like the popular ones such as nabilone, dronabinol, and Δ9-tetrahydrocannabinol mediates its action through CB1/CB2 receptors. However, these synthetic based Cannabis derived compounds are known to exert adverse psychiatric effect and have also been exploited for drug abuse. This encourages us to find out an alternative and safe drug with the least psychiatric adverse effects. In recent years, many phytocannabinoids have been isolated from plants other than Cannabis. Several studies have shown that these phytocannabinoids show affinity, potency, selectivity, and efficacy towards cannabinoid receptors and inhibit endocannabinoid metabolizing enzymes, thus reducing hyperactivity of endocannabinoid systems. Also, these naturally derived molecules possess the least adverse effects opposed to the synthetically derived cannabinoids. Therefore, the plant based cannabinoid molecules proved to be promising and emerging therapeutic alternative. The present review provides an overview of therapeutic potential of ligands and plants modulating cannabinoid receptors that may be of interest to pharmaceutical industry in search of new and safer drug discovery and development for future therapeutics. PMID:26664449
Luo, J; Fort, D M; Carlson, T J; Noamesi, B K; nii-Amon-Kotei, D; King, S R; Tsai, J; Quan, J; Hobensack, C; Lapresca, P; Waldeck, N; Mendez, C D; Jolad, S D; Bierer, D E; Reaven, G M
1998-05-01
Evidence has been published that a wide array of plant-derived active principles, representing numerous classes of chemical compounds, demonstrate activity consistent with their possible use in the treatment of patients with Type 2 diabetes mellitus (DM). Despite these interesting observations, to date, metformin is the only ethical drug approved for treatment of Type 2 DM derived from a medicinal plant. Why is this so, given the fact that higher plants are such a potential source of new drugs? The answer to this rhetorical question may lie in the reliance of most pharmaceutical companies on random, in vitro, mechanism-based, high throughput screening in the initial phases of plant drug research. In this article we describe an alternative pathway to discovery of drugs for the treatment of Type 2 DM: on based on an ethnomedical approach, involving ethnobotany and traditional medicine. In particular, we present evidence that cryptolepine, an indoloquinolone alkaloid isolated from Cryptolepis sanguinolenta, significantly lowers glucose when given orally to a mouse model of diabetes. The antihyperglycaemic effect of cryptolepine leads to a significant decline in plasma insulin concentration, associated with evidence of an enhancement in insulin-mediated glucose disposal. Finally, cryptolepine increases glucose uptake by 3T3-L1 cells. These data permit us to conclude that an ethnobotanical approach to drug discovery can identify a potentially useful drug for the treatment of Type 2 DM. PMID:9609357
Veltman, Martinus J. G.
1986-01-01
Reports recent findings related to the particle Higgs boson and examines its possible contribution to the standard mode of elementary processes. Critically explores the strengths and uncertainties of the Higgs boson and proposed Higgs field. (ML)
Mesua beccariana (Clusiaceae, A Source of Potential Anti-cancer Lead Compounds in Drug Discovery
Directory of Open Access Journals (Sweden)
Soek Sin Teh
2012-09-01
Full Text Available An investigation on biologically active secondary metabolites from the stem bark of Mesua beccariana was carried out. A new cyclodione, mesuadione (1, along with several known constituents which are beccamarin (2, 2,5-dihydroxy-1,3,4-trimethoxy anthraquinone (3, 4-methoxy-1,3,5-trihydroxyanthraquinone (4, betulinic acid (5 and stigmasterol (6 were obtained from this ongoing research. Structures of these compounds were elucidated by extensive spectroscopic methods, including 1D and 2D-NMR, GC-MS, IR and UV techniques. Preliminary tests of the in vitro cytotoxic activities of all the isolated metabolites against a panel of human cancer cell lines Raji (lymphoma, SNU-1 (gastric carcinoma, K562 (erythroleukemia cells, LS-174T (colorectal adenocarcinoma, HeLa (cervical cells, SK-MEL-28 (malignant melanoma cells, NCI-H23 (lung adenocarcinoma, IMR-32 (neuroblastoma and Hep-G2 (hepatocellular liver carcinoma were carried out using an MTT assay. Mesuadione (1, beccamarin (2, betulinic acid (5 and stigmasterol (6 displayed strong inhibition of Raji cell proliferation, while the proliferation rate of SK-MEL-28 and HeLa were strongly inhibited by stigmasterol (6 and beccamarin (2, indicating these secondary metabolites could be anti-cancer lead compounds in drug discovery.
Therapeutic Potential of Plants as Anti-Microbials for Drug Discovery
Directory of Open Access Journals (Sweden)
Ramar Perumal Samy
2010-01-01
Full Text Available The uses of traditional medicinal plants for primary health care have steadily increased worldwide in recent years. Scientists are in search of new phytochemicals that could be developed as useful anti-microbials for treatment of infectious diseases. Currently, out of 80% of pharmaceuticals derived from plants, very few are now being used as anti-microbials. Plants are rich in a wide variety of secondary metabolites that have found anti-microbial properties. This review highlights the current status of traditional medicine, its contribution to modern medicine, recent trends in the evaluation of anti-microbials with a special emphasis upon some tribal medicine, in vitro and in vivo experimental design for screening, and therapeutic efficacy in safety and human clinical trails for commercial outlet. Many of these commercially available compounds are crude preparations administered without performing human clinical trials. Recent methods are useful to standardize the extraction for scientific investigation of new phytochemicals and anti-microbials of traditionally used plants. It is concluded that once the local ethnomedical preparations of traditional sources are scientifically evaluated before dispensing they should replace existing drugs commonly used for the therapeutic treatment of infection. This method should be put into practice for future investigations in the field of ethnopharmacology, phytochemistry, ethnobotany and other biological fields for drug discovery.
Potential of Glutamate-Based Drug Discovery for Next Generation Antidepressants
Directory of Open Access Journals (Sweden)
Shigeyuki Chaki
2015-09-01
Full Text Available Recently, ketamine has been demonstrated to exert rapid-acting antidepressant effects in patients with depression, including those with treatment-resistant depression, and this discovery has been regarded as the most significant advance in drug development for the treatment of depression in over 50 years. To overcome unwanted side effects of ketamine, numerous approaches targeting glutamatergic systems have been vigorously investigated. For example, among agents targeting the NMDA receptor, the efficacies of selective GluN2B receptor antagonists and a low-trapping antagonist, as well as glycine site modulators such as GLYX-13 and sarcosine have been demonstrated clinically. Moreover, agents acting on metabotropic glutamate receptors, such as mGlu2/3 and mGlu5 receptors, have been proposed as useful approaches to mimicking the antidepressant effects of ketamine. Neural and synaptic mechanisms mediated through the antidepressant effects of ketamine have been being delineated, most of which indicate that ketamine improves abnormalities in synaptic transmission and connectivity observed in depressive states via the AMPA receptor and brain-derived neurotrophic factor-dependent mechanisms. Interestingly, some of the above agents may share some neural and synaptic mechanisms with ketamine. These studies should provide important insights for the development of superior pharmacotherapies for depression with more potent and faster onsets of actions.
Higgs boson : production and decays into bosons
Escalier, Marc; The ATLAS collaboration
2016-01-01
The results on the Higgs boson with decay channels into bosons from the ATLAS and CMS experiments at LHC Run 1 and early Run 2 are reviewed in the context of the Standard Model. : observation of a signal, measurement of mass, width, spin, cross-sections, search for decay channels and production modes, Higgs couplings to various particles.
Bosonization and quantum hydrodynamics
Indian Academy of Sciences (India)
Girish S Setlur
2006-03-01
It is shown that it is possible to bosonize fermions in any number of dimensions using the hydrodynamic variables, namely the velocity potential and density. The slow part of the Fermi field is defined irrespective of dimensionality and the commutators of this field with currents and densities are exponentiated using the velocity potential as conjugate to the density. An action in terms of these canonical bosonic variables is proposed that reproduces the correct current and density correlations. This formalism in one dimension is shown to be equivalent to the Tomonaga-Luttinger approach as it leads to the same propagator and exponents. We compute the one-particle properties of a spinless homogeneous Fermi system in two spatial dimensions with long-range gauge interactions and highlight the metal-insulator transition in the system. A general formula for the generating function of density correlations is derived that is valid beyond the random phase approximation. Finally, we write down a formula for the annihilation operator in momentum space directly in terms of number conserving products of Fermi fields.
Neutral Higgs boson search at Tevatron
Energy Technology Data Exchange (ETDEWEB)
Yao, Wei-Ming; /LBL, Berkeley
2004-11-01
The authors review searches for neutral Higgs Boson performed by the CDF and D0 collaborations using approximately 200 pb{sup -1} of the dataset accumulated from p{bar p} collisions at the center-of-mass energy of 1.96 TeV. No signals are found and limits on the Standard Model (SM) Higgs or SM-like Higgs production cross section times branching ratio and couplings of the Higgs boson in MSSM are presented, including the future prospects of discovery Higgs at the end of Run II.
Searches for BSM Higgs Bosons with ATLAS
Navarro, Gabriela; The ATLAS collaboration
2015-01-01
The discovery of a Higgs-like boson with a mass of about 125GeV has prompted the question of whether or not this particle is part of a much larger and more complex Higgs sector than that envisioned in the Standard Model. In this talk, the current results from the ATLAS Experiment regarding Beyond-the-Standard Model (BSM) Higgs hypothesis tests are outlined. Searches for additional Higgs bosons are presented and interpreted in well-motivated BSM Higgs frameworks, such as two-Higgs-doublet Models and the Minimal Supersymmetric Standard Model.
Various Models Mimicking the SM Higgs Boson
Chang, Jung; Tseng, Po-Yan; Yuan, Tzu-Chiang; 10.1142/S0217751X1230030X
2012-01-01
This review is based on the talk presented at the SUSY 2012 (Beijing). The new particle around 125 GeV observed at the Large Hadron Collider (LHC) is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. While at the LHC the dominant production mechanism for the Higgs boson of the standard model and some other extensions is via the gluon fusion process, the alternative vector-boson fusion is more sensitive to electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.
The potential use of SUISEKI as a protein interaction discovery tool.
Blaschke, C; Valencia, A
2001-01-01
Relevant information about protein interactions is stored in textual sources. This sources are commonly used not only as archives of what is already known but also as information for generating new knowledge, particularly to pose hypothesis about new possible interactions that can be inferred from the existing ones. This task is the more creative part of scientific work in experimental systems. We present a large-scale analysis for the prediction of new interactions based on the interaction network for the ones already known and detected automatically in the literature. During the last few years it has became clear that part of the information about protein interactions could be extracted with automatic tools, even if these tools are still far from perfect and key problems such as detection of protein names are not completely solved. We have developed a integrated automatic approach, called SUISEKI (System for Information Extraction on Interactions), able to extract protein interactions from collections of Medline abstracts. Previous experiments with the system have shown that it is able to extract almost 70% of the interactions present in relatively large text corpus, with an accuracy of approximately 80% (for the best defined interactions) that makes the system usable in real scenarios, both at the level of extraction of protein names and at the level of extracting interaction between them. With the analysis of the interaction map of Saccharomyces cerevisiae we show that interactions published in the years 2000/2001 frequently correspond to proteins or genes that were already very close in the interaction network deduced from the literature published before these years and that they are often connected to the same proteins. That is, discoveries are commonly done among highly connected entities. Some biologically relevant examples illustrate how interactions described in the year 2000 could have been proposed as reasonable working hypothesis with the information
Walhart, Tara
2015-01-01
Persistent oncogenic human papillomavirus (HPV) infection increases the probability that precancerous anal high-grade squamous intraepithelial lesions will progress to invasive anal cancer. Anal neoplasia associated with HPV disproportionately affects HIV-infected individuals, especially men who have sex with men. Prevention is limited to HPV vaccine recommendations, highlighting the need for new treatments. The purpose of this review is to provide HIV information to nurse clinical scientists about HPV-related cancer to highlight the connection between: (a) HPV biology and pathogenesis and (b) the development of drugs and novel therapeutic methods using high-throughput screening. PubMed and CINAHL were used to search the literature to determine HPV-related epidemiology, biology, and use of high-throughput screening for drug discovery. Several events in the HPV life cycle have the potential to be developed into biologic targets for drug discovery using the high-throughput screening technique, which has been successfully used to identify compounds to inhibit HPV infections. PMID:26277046
Lundkvist, Johan; Halldin, Magnus M.; Sandin, Johan; Nordvall, Gunnar; Forsell, Pontus; Svensson, Samuel; Jansson, Liselotte; Johansson, Gunilla; Winblad, Bengt; Ekstrand, Jonas
2014-01-01
Alzheimer’s Disease (AD) is the most common form of dementia, affecting approximately 36 million people worldwide. To date there is no preventive or curative treatment available for AD, and in absence of major progress in therapeutic development, AD manifests a concrete socioeconomic threat. The awareness of the growing problem of AD is increasing, exemplified by the recent G8 Dementia Summit, a meeting held in order to set the stage and steer the compass for the future. Simultaneously, and paradoxically, we have seen key players in the pharmaceutical industry that have recently closed or significantly decreased their R&D spending on AD and other CNS disorders. Given the pressing need for new treatments in this area, other actors need to step-in and enter this drug discovery arena complementing the industrial efforts, in order to turn biological and technological progress into novel therapeutics. In this article, we present an example of a novel drug discovery initiative that in a non-profit setting, aims to integrate with both preclinical and clinical academic groups and pharmaceutical industry to explore the therapeutic potential of new concepts in patients, using novel biology, state of the art technologies and rapid concept testing. PMID:24847271
Directory of Open Access Journals (Sweden)
Johan eLundkvist
2014-05-01
Full Text Available Alzheimer Disease (AD is the most common form of dementia, affecting approximately 36 million people worldwide. To date there is no preventive or curative treatment available for AD, and in absence of major progress in therapeutic development, AD manifests a concrete socioeconomic threat. The awareness of the growing problem of AD is increasing, exemplified by the recent G8 Dementia Summit, a meeting held in order to set the stage and steer the compass for the future. Simultaneously, and paradoxically, we have seen key players in the pharmaceutical industry that have recently closed or significantly decreased their R&D spending on AD and other CNS disorders. Given the pressing need for new treatments in this area, other actors need to step-in and enter this drug discovery arena complementing the industrial efforts, in order to turn biological and technological progress into novel therapeutics. In this article, we present an example of a novel drug discovery initiative that in a non-profit setting, aims to integrate with both preclinical and clinical academic groups and pharmaceutical industry to explore the therapeutic potential of new concepts in patients, using novel biology, state of the art technologies and rapid concept
In Silico discovery of transcription factors as potential diagnostic biomarkers of ovarian cancer
Kaur, Mandeep
2011-09-19
Background: Our study focuses on identifying potential biomarkers for diagnosis and early detection of ovarian cancer (OC) through the study of transcription regulation of genes affected by estrogen hormone.Results: The results are based on a set of 323 experimentally validated OC-associated genes compiled from several databases, and their subset controlled by estrogen. For these two gene sets we computationally determined transcription factors (TFs) that putatively regulate transcription initiation. We ranked these TFs based on the number of genes they are likely to control. In this way, we selected 17 top-ranked TFs as potential key regulators and thus possible biomarkers for a set of 323 OC-associated genes. For 77 estrogen controlled genes from this set we identified three unique TFs as potential biomarkers.Conclusions: We introduced a new methodology to identify potential diagnostic biomarkers for OC. This report is the first bioinformatics study that explores multiple transcriptional regulators of OC-associated genes as potential diagnostic biomarkers in connection with estrogen responsiveness. We show that 64% of TF biomarkers identified in our study are validated based on real-time data from microarray expression studies. As an illustration, our method could identify CP2 that in combination with CA125 has been reported to be sensitive in diagnosing ovarian tumors. 2011 Kaur et al; licensee BioMed Central Ltd.
Discovery Potential for the Neutral Charmonium-Like Z0(4200) by p-p Annihilation
International Nuclear Information System (INIS)
Inspired by the observation of charmonium-like Z(4200), we explore the discovery potential of the neutral Z0(4200) production by antiproton-proton annihilation with an effective Lagrangian approach. By investigating the p-p→J/ψπ0 process including the Z0(4200) signal and background contributions, it is found that the center of mass energy Ec.m.≃ 4.0–4.5 GeV is the best energy window for searching the neutral Z0(4200), where the signal can be clearly distinguished from background. The relevant calculations not only are helpful to search for the neutral Z0(4200) in the future experiment but also will promote the understanding of the nature and production mechanism of neutral Z0(4200) better
Directory of Open Access Journals (Sweden)
Shuwei Feng
2015-01-01
Full Text Available The prevalence of vascular dementia (VaD is high among the elderly. Acupuncture, a popular therapeutic method in China, can improve memory, orientation, calculation, and self-managing ability in VaD patients. However, in clinical acupuncture and acupuncture research, the selection of acupoints to treat VaD remains challenging. This study aimed to discover acupoints and acupoint combinations with potential for VaD based on data mining. After database searching and screening for articles on clinical trials evaluating the effects of acupuncture on VaD, 238 acupuncture prescriptions were included for further analysis. Baihui (GV 20, Sishencong (EX-HN 1, Fengchi (GB 20, Shuigou (GV 26, and Shenting (GV 24 appeared most frequently in the modern literature and are potential acupoints for VaD. Combinations between Baihui (GV 20, Sishencong (EX-HN 1, Fengchi (GB 20, Shenting (GV 24, Shuigou (GV 26, and Zusanli (ST 36 were most frequent and represent potential combinations for VaD treatment. These results provide a reference for the selection and combination of acupoints to treat VaD in clinical acupuncture and acupuncture research.
Macchines per scoprire - Discovery Machines
Auditorium, Rome
2016-01-01
During the FCC week 2016 a public event entitled “Discovery Machines: The Higgs Boson and the Search for New Physics took place on 14 April at the Auditorium in Rome. The event, brought together physicists and experts from economics to discuss intriguing questions on the origin and evolution of the Universe and the societal impact of large-scale research projects.
Searches for the Higgs-like boson decaying into bottom quarks in the WH channel
International Nuclear Information System (INIS)
The most important finding of the LHC so far was the discovery of the Higgs-like boson at 125 GeV in 2012. We present the most recent results of the search for the Higgs-like boson decaying into bottom quarks, when produced in association with a W boson. Only events where the leptonically decaying W boson and the Higgs boson possess large transverse momenta are selected. The full proton-proton collision data recorded by the CMS detector in 2011 and 2012 at 7 and 8 TeV respectively, corresponding to an integrated luminosity of 24/fb, is used for the search. (authors)
Verma, Priyanka; Dalal, Krishna; Chopra, Madhu
2016-08-01
In the development of osteoarthritis, aggrecan degrades prior to cartilage destruction. Aggrecanase-1 (ADAMTS-4) is considered to be the major enzyme responsible for cleaving the Glu373-Ala374 bond in the interglobular domain of aggrecan in humans. Therefore, inhibitors of ADAMTS-4 have therapeutic potential in the treatment of osteoarthritis. In the present work, we developed a chemical feature based pharmacophore model of ADAMTS-4 inhibitors using the HipHop module within the Catalyst program package in order to elucidate the structure-activity relationship and to carry out in-silico screening. The Maybridge database was screened using Hypo1 as a 3D query, and the best-fit hits that followed Lipinski's rule of five were subsequently screened to select the compounds. The hit compounds were then docked into the active site of ADAMTS-4, and interactions were visualized to determine the potential lead molecules. After subjecting all of the hits to various screening and filtering processes, 13 compounds were finally evaluated for their in vitro inhibitory activities. This study resulted in the identification of two lead compounds with potent inhibitory effects on ADAMTS-4 activity, with IC50 values of 0.042 μM and 0.028 μM, respectively. These results provide insight into the pharmacophoric requirements for the development of more potent ADAMTS-4 inhibitors. Graphical Abstract The aggrecan-degrading metalloprotease ADAMTS-4 has been identified as a novel therapeutic target for osteoarthritis. In this work, we used HipHop-based pharmacophore modeling and virtual screening of the Maybridge database to identify novel ADAMTS-4 inhibitors. These novel lead compounds act as potent and specific inhibitors for the ADAMTS-4 enzyme and could have therapeutic potential in the treatment of OA. PMID:27401455
Kanhed, Ashish M; Sinha, Anshuman; Machhi, Jatin; Tripathi, Ashutosh; Parikh, Zalak S; Pillai, Prakash P; Giridhar, Rajani; Yadav, Mange Ram
2015-08-01
This article describes discovery of a novel and new class of cholinesterase inhibitors as potential therapeutics for Alzheimer's disease. A series of novel isoalloxazine derivatives were synthesized and biologically evaluated for their potential inhibitory outcome for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). These compounds exhibited high activity against both the enzymes AChE as well as BuChE. Of the synthesized compounds, the most potent isoalloxazine derivatives (7m and 7q) showed IC50 values of 4.72 μM and 5.22 μM respectively against AChE; and, 6.98 μM and 5.29 μM respectively against BuChE. These two compounds were further evaluated for their anti-aggregatory activity for β-amyloid (Aβ) in presence and absence of AChE by performing Thioflavin-T (ThT) assay and Congo red (CR) binding assay. In order to evaluate cytotoxic profile of these two potential compounds, cell viability assay of SH-SY5Y human neuroblastoma cells was performed. Further, to understand the binding behavior of these two compounds with AChE and BuChE enzymes, docking studies have been reported. PMID:26042530
Discovery and Identification of W' and Z' in SU(2) x SU(2) x U(1) Models at the LHC
Cao, Qing-Hong; Li, Zhao; Yu, Jiang-Hao; Yuan, C.-P.
2012-01-01
We explore the discovery potential of W' and Z' boson searches for various SU(2) x SU(2) x U(1) models at the Large Hadron Collider (LHC), after taking into account the constraints from low energy precision measurements and direct searches at both the Tevatron (1.96 TeV) and the LHC (7 TeV). In such models, the W' and Z' bosons emerge after the electroweak symmetry is spontaneously broken. Two patterns of the symmetry breaking are considered in this work: one is SU(2)_L x SU(2)_2 x U(1)_X to ...
A light Higgs Boson would invite Supersymmmetry
Ellis, Jonathan Richard; Ellis, John; Ross, Douglas
2001-01-01
If the Higgs boson weighs about 115 GeV, the effective potential of the Standard Model becomes unstable above a scale of about 10^6 GeV. This instability may be rectified only by new bosonic particles such as stop squarks. However, avoiding the instability requires fine-tuning of the model couplings, in particular if the theory is not to become non-perturbative before the Planck scale. Such fine-tuning is automatic in a supersymmetric model, but is lost if there are no Higgsinos. A light Higgs boson would be prima facie evidence for supersymmetry in the top-quark and Higgs sectors.
Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery
Directory of Open Access Journals (Sweden)
Cheeptham N.
2013-01-01
Full Text Available Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the f irst study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locat ions were plot ted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca, iron (Fe, and aluminum (Al were the most abundant components while magnesium (Mg, sodium (Na, arsenic (As, lead (Pb, chromium (Cr, and barium (Ba were second most abundant with cadmium (Cd and potassium (K were the least abundant in our samples. Scanning electron microscopy (SEM showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3% of the strains belong to the Streptomyces genus and 5 (6.1% were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6% of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. ezbiocloud.net/ to determine whether
Discovery potential for supernova relic neutrinos with slow liquid scintillator detectors
Wei, Hanyu; Chen, Shaomin
2016-01-01
The detection of supernova relic neutrinos would provide a key support for our current understanding of stellar and cosmological evolution, and precise measurements of them would further give us an insight of the profound universe. In this paper we study the potential to detect supernova relic neutrinos using linear alkyl benzene, LAB, as a slow liquid scintillator, which features a good separation of Cherenkov and scintillation lights, thus providing a new ability in particle identification. We also address key issues of current experiments, including 1) the charged current background of atmospheric neutrinos in water Cherenkov detectors, and 2) the neutral current background of atmospheric neutrinos in typical liquid scintillator detectors. With LAB, a kiloton-scale detector, like the SNO, KamLAND, and the future Jinping neutrino detectors, with $\\mathcal{O}$(10) years of data, would have the sensitivity to discover supernova relic neutrinos, which is comparable to large-volume water Cherenkov, typical liqu...
Sumoylation in gene regulation and cardiac disease: potential for drug discovery
Directory of Open Access Journals (Sweden)
Beketaev I
2014-11-01
Full Text Available Ilimbek Beketaev, Jun Wang Center for Stem Cell Engineering, Department of Basic Research Laboratories, Texas Heart Institute at St Luke’s Episcopal Hospital, Houston, TX, USA Abstract: Small ubiquitin-related modifier (SUMO proteins are members of ubiquitin-like super-family proteins that can be covalently conjugated to their targets through multistep enzymatic reactions. Sumoylation has caught much attention due to its versatility, wide involvement in cellular events, and disease association. Sumoylation has been well studied at cellular and molecular levels. A newly emerging role that SUMO conjugation plays is in cardiac pathophysiology. In this review we will update new advances in the study of implications of the sumoylation pathway in the pathogenesis of cardiac diseases, discuss promise of the SUMO pathway as a potential therapeutic target, and conclude with future directions for SUMO research in the heart field. Keywords: posttranslational modification, SUMO, SENP, heart
Bosonic behavior of entangled fermions
DEFF Research Database (Denmark)
C. Tichy, Malte; Alexander Bouvrie, Peter; Mølmer, Klaus
2012-01-01
Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle does not affect the behavior of many such composite bosons. The departure of ideal bosonic behavior is quantified by the normalization ratio of multi-composite-boson st......Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle does not affect the behavior of many such composite bosons. The departure of ideal bosonic behavior is quantified by the normalization ratio of multi...
Prospects for Higgs boson searches at the Large Hadron Collider
Indian Academy of Sciences (India)
B Mellado
2009-01-01
These proceedings summarize the sensitivity for the CMS and ATLAS experiments at the LHC to discover a Standard Model Higgs boson with relatively low integrated luminosity per experiment. The most relevant discovery modes are dealt with. A brief discussion on the expected performance from these experiments in searches for one or more of the Higgs bosons from the minimal version of the supersymmetric theories is also included.
Enhanced Higgs boson to τ(+)τ(-) search with deep learning.
Baldi, P; Sadowski, P; Whiteson, D
2015-03-20
The Higgs boson is thought to provide the interaction that imparts mass to the fundamental fermions, but while measurements at the Large Hadron Collider (LHC) are consistent with this hypothesis, current analysis techniques lack the statistical power to cross the traditional 5σ significance barrier without more data. Deep learning techniques have the potential to increase the statistical power of this analysis by automatically learning complex, high-level data representations. In this work, deep neural networks are used to detect the decay of the Higgs boson to a pair of tau leptons. A Bayesian optimization algorithm is used to tune the network architecture and training algorithm hyperparameters, resulting in a deep network of eight nonlinear processing layers that improves upon the performance of shallow classifiers even without the use of features specifically engineered by physicists for this application. The improvement in discovery significance is equivalent to an increase in the accumulated data set of 25%. PMID:25839260
Enhanced Higgs Boson to τ+τ- Search with Deep Learning
Baldi, P.; Sadowski, P.; Whiteson, D.
2015-03-01
The Higgs boson is thought to provide the interaction that imparts mass to the fundamental fermions, but while measurements at the Large Hadron Collider (LHC) are consistent with this hypothesis, current analysis techniques lack the statistical power to cross the traditional 5 σ significance barrier without more data. Deep learning techniques have the potential to increase the statistical power of this analysis by automatically learning complex, high-level data representations. In this work, deep neural networks are used to detect the decay of the Higgs boson to a pair of tau leptons. A Bayesian optimization algorithm is used to tune the network architecture and training algorithm hyperparameters, resulting in a deep network of eight nonlinear processing layers that improves upon the performance of shallow classifiers even without the use of features specifically engineered by physicists for this application. The improvement in discovery significance is equivalent to an increase in the accumulated data set of 25%.
Higgs Quantum Numbers in Weak Boson Fusion
Englert, Christoph; Gonçalves-Netto, Dorival; Mawatari, Kentarou; Plehn, Tilman
2012-01-01
Recently, the ATLAS and CMS experiments have reported the discovery of a Higgs like resonance at the LHC. The next analysis step will include the determination of its spin and CP quantum numbers or the form of its interaction Lagrangian channel-by-channel. We show how weak-boson-fusion Higgs production and associated ZH production can be used to separate different spin and CP states.
Taratuta, Rostislav
2015-01-01
The main purpose of this paper is to introduce the new bosonic mechanism and newtreatment of dark energy. The bosonic mechanism focuses on obtaining masses by gauge bosonswithout assuming the existence of Higgs boson. The hypothesis on dark energy as the energy ofa postulated dark field was made and a combined gravitational-dark field was introduced. This fieldis the key to a specified approach and allows addressing the fundamental starting points of the mechanism.i. Complex scalar field is i...
A comparison of the Higgs sectors of the CMSSM and NMSSM for a 126 GeV Higgs boson
International Nuclear Information System (INIS)
The recent discovery of a Higgs-like boson at the LHC with a mass of 126 GeV has revived the interest in supersymmetric models, which predicted a Higgs boson mass below 130 GeV long before its discovery. We compare systematically the allowed parameter space in the constrained Minimal Supersymmetric Standard Model (CMSSM) and the Next-to-Minimal Supersymmetric Model (NMSSM) by minimizing the χ2 function with respect to all known constraints from accelerators and cosmology using GUT scale parameters. For the CMSSM the Higgs boson mass at tree level is below the Z0 boson mass and large radiative corrections are needed to obtain a Higgs boson mass of 126 GeV, which requires stop squark masses in the multi-TeV range. In contrast, for the NMSSM light stop quarks are allowed, since in the NMSSM at tree level the Higgs boson mass can be above the Z0 boson mass from mixing with the additional singlet Higgs boson. Predictions for the scalar boson masses are given in both models with emphasis on the unique signatures of the NMSSM, where the heaviest scalar Higgs boson decays in the two lighter scalar Higgs bosons with a significant branching ratio, in which case one should observe double Higgs boson production at the LHC. Such a signal is strongly suppressed in the CMSSM. In addition, since the LSP is higgsino-like, Higgs boson decays into LSPs can be appreciable, thus leading to invisible Higgs decays
Production of electroweak bosons at hadron colliders: theoretical aspects
Mangano, Michelangelo L
2015-01-01
Since the W and Z discovery, hadron colliders have provided a fertile ground, in which continuously improving measurements and theoretical predictions allow to precisely determine the gauge boson properties, and to probe the dynamics of electroweak and strong interactions. This article will review, from a theoretical perspective, the role played by the study, at hadron colliders, of electroweak boson production properties, from the better understanding of the proton structure, to the discovery and studies of the top quark and of the Higgs, to the searches for new phenomena beyond the Standard Model.
Searching for Additional Higgs Bosons via Higgs Cascades
Gao, Christina; Mulhearn, Michael; Neill, Nicolás A; Wang, Zhangqier
2016-01-01
The discovery of a 125 GeV Higgs boson at the Large Hadron Collider strongly motivates direct searches for additional Higgs bosons. In a type I two Higgs doublet model there is a large region of parameter space at $\\tan\\beta > 5$ that is currently unconstrained experimentally. We show that the process $gg \\to H \\to A Z \\to ZZh$ can probe this region, and can be the discovery mode for an extended Higgs sector at the LHC. We analyze 9 promising decay modes for the $ZZh$ state, and we find that the most sensitive final states are $\\ell\\ell\\ell\\ell bb$, $\\ell\\ell jjbb$, $\\ell\\ell\
Spontaneous Emission of Charged Bosons from Supercritical Point Charges
Kim, Sang Pyo
2013-01-01
We study the spontaneous emission of charged bosons from supercritical Coulomb potentials and charged black holes. We find the exact emission rate from the Bogoliubov transformation by applying the tunneling boundary condition on the Jost functions at the asymptotic boundaries. The emission rate for charged bosons in the supercritical Coulomb potential increases as the charge $Z\\alpha > 1/2$ of the superatom and the energy of the bosons increase but is suppressed for large angular momenta. We discuss physical implications of the emission of charged bosons from superatoms and charged black holes.
Search for the Higgs boson in fermionic channels using the ATLAS detector
Directory of Open Access Journals (Sweden)
Hageböck Stephan
2015-01-01
Full Text Available Since the discovery of the Higgs boson by the ATLAS and CMS experiments at the LHC, the emphasis has shifted towards measurements of its properties. Of particular importance is the direct observation of the coupling of the Higgs boson to fermions. A review of ATLAS results in the search for the Higgs boson in tau, muon and b-quark pairs is presented.
International Nuclear Information System (INIS)
We present two open-source (BSD) implementations of ellipsoidal harmonic expansions for solving problems of potential theory using separation of variables. Ellipsoidal harmonics are used surprisingly infrequently, considering their substantial value for problems ranging in scale from molecules to the entire solar system. In this paper, we suggest two possible reasons for the paucity relative to spherical harmonics. The first is essentially historical—ellipsoidal harmonics developed during the late 19th century and early 20th, when it was found that only the lowest-order harmonics are expressible in closed form. Each higher-order term requires the solution of an eigenvalue problem, and tedious manual computation seems to have discouraged applications and theoretical studies. The second explanation is practical: even with modern computers and accurate eigenvalue algorithms, expansions in ellipsoidal harmonics are significantly more challenging to compute than those in Cartesian or spherical coordinates. The present implementations reduce the 'barrier to entry' by providing an easy and free way for the community to begin using ellipsoidal harmonics in actual research. We demonstrate our implementation using the specific and physiologically crucial problem of how charged proteins interact with their environment, and ask: what other analytical tools await re-discovery in an era of inexpensive computation?
Energy Technology Data Exchange (ETDEWEB)
Warsinsky, Markus
2008-09-15
This thesis presents a Monte Carlo study of neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) decaying into muons at the ATLAS experiment at the CERN Large Hadron Collider. Signal and background processes are simulated using novel Monte Carlo generators that incorporate parts of higher order corrections and are expected to give a more accurate prediction than previous programs. The SHERPA Monte Carlo generator is validated for its use in the analysis and compared to results obtained with other programs. Where possible, the Monte Carlo event samples are normalized to higher order calculations. To increase the available Monte Carlo statistics, this study is based on the ATLAS fast detector simulation ATLFAST. Differences between ATLFAST and the detailed detector simulation of ATLAS are examined, and, where possible, correction procedures are devised. A cut based analysis is performed assuming an integrated luminosity of 30 fb{sup -1}, and optimized with respect to the discovery potential for MSSM Higgs bosons. The systematic uncertainties of the event selection and the Monte Carlo predictions are estimated. A method that can be used to estimate the background from data is presented and evaluated. Last, the discovery potential of the ATLAS experiment in the CP conserving benchmark scenarios of the MSSM is evaluated. One or more of the neutral Higgs bosons of the MSSM can be discovered in the muonic decay mode using 30 fb{sup -1} of data for low masses of the pseudoscalar boson A{sup 0}, if the model parameter tan {beta} is at least 20. For higher masses of the A{sup 0}, tan {beta} would need to be significantly higher to ensure a discovery in the studied decay channel. The sensitivity of ATLAS to MSSM Higgs bosons is multiple times larger than the one of previous and currently running experiments. (orig.)
International Nuclear Information System (INIS)
This thesis presents a Monte Carlo study of neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) decaying into muons at the ATLAS experiment at the CERN Large Hadron Collider. Signal and background processes are simulated using novel Monte Carlo generators that incorporate parts of higher order corrections and are expected to give a more accurate prediction than previous programs. The SHERPA Monte Carlo generator is validated for its use in the analysis and compared to results obtained with other programs. Where possible, the Monte Carlo event samples are normalized to higher order calculations. To increase the available Monte Carlo statistics, this study is based on the ATLAS fast detector simulation ATLFAST. Differences between ATLFAST and the detailed detector simulation of ATLAS are examined, and, where possible, correction procedures are devised. A cut based analysis is performed assuming an integrated luminosity of 30 fb-1, and optimized with respect to the discovery potential for MSSM Higgs bosons. The systematic uncertainties of the event selection and the Monte Carlo predictions are estimated. A method that can be used to estimate the background from data is presented and evaluated. Last, the discovery potential of the ATLAS experiment in the CP conserving benchmark scenarios of the MSSM is evaluated. One or more of the neutral Higgs bosons of the MSSM can be discovered in the muonic decay mode using 30 fb-1 of data for low masses of the pseudoscalar boson A0, if the model parameter tan β is at least 20. For higher masses of the A0, tan β would need to be significantly higher to ensure a discovery in the studied decay channel. The sensitivity of ATLAS to MSSM Higgs bosons is multiple times larger than the one of previous and currently running experiments. (orig.)
2008-01-01
Quantum physicists think they know the answer. Probabilistic calculations reveal than the data provided by previous experiments has been miscalculated and that the Higgs boson has in fact been discovered. Weird! The Higgs boson is the only particle predicted by the Standard Model that hasn't been discovered yet.
Ravat, O
2004-01-01
CMS The quest for the Higgs boson, is one of the mains goals of the CMS detector, which will be operated at the next proton-proton collider LHC. In this thesis, the electromagnetic calorimeter is involved.In the first part of this thesis the ECAL performance is evaluated with the data taken during the 2003 beam tests. The choices concerning the electronics readout have been made.The second part uses the ECAL in order to evaluate the discovery potential of the Higgs boson in the associated ...
Higgs to gamma gamma in association with Z/W bosons
Brelier, B
2008-01-01
Electro-weak precision measurements strongly suggest that the mass of the Standard Model Higgs boson, if it exists, should not be much higher than the present experimental limit of 114.4 GeV. The LHC experiments will allow us to look for a Higgs boson in this mass range for which the decay into photons is one of the most important channels. The isolation of events from Higgs boson production in association with Z/W bosons may increase the statistical significance of the Higgs boson discovery and these production modes can be used to measure directly the Higgs boson couplings to the weak bosons, thus helping to confirm the nature of the observed resonance.
Pimenta, Jean Jûnio Mendes; Natti, Érica Regina Takano; Natti, Paulo Laerte
2013-01-01
The Higgs boson was predicted in 1964 by British physicist Peter Higgs. The Higgs is the key to explain the origin of the mass of other elementary particles of Nature. However, only with the coming into operation of the LHC, in 2008, there were technological conditions to search for the Higgs boson. Recently, a major international effort conducted at CERN, by means of ATLAS and CMS experiments, has enabled the observation of a new bosonic particle in the region of 125 GeVs. In this paper, by means of known mechanisms of symmetry breaking that occur in the BCS theory of superconductivity and in the theory of nuclear pairing, we discuss the Higgs mechanism in the Standard Model. Finally, we present the current state of research looking for the Higgs boson and the alternative theories and extensions of the Standard Model for the elementary particle physics. Keywords: Higgs boson, BCS theory, nuclear pairing, Higgs mechanism, Standard Model.
International Nuclear Information System (INIS)
We report on the development of search methods for point-like and extended neutrino sources, utilizing the tracking and energy estimation capabilities of an underwater, Very Large Volume Neutrino Telescope (VLVnT). We demonstrate that the developed techniques offer a significant improvement on the telescope's discovery potential. We also present results on the potential of the Mediterranean KM3NeT to discover galactic neutrino sources
Enberg, Rikard; Moretti, Stefano; Munir, Shoaib; Wouda, Glenn
2015-01-01
The recent observation of a 125 GeV neutral Higgs boson ($H_{\\rm obs}$) provides additional input for charged Higgs boson searches in the $H^\\pm \\to W^\\pm H_{\\rm obs}$ decay channel at the Large Hadron Collider (LHC). We reassess the discovery potential in this channel, which is important for $H^\\pm$ heavier than the top quark mass. When $H_{\\rm obs}$ decays to a $b\\bar{b}$ pair, knowledge of the Higgs mass aids in the kinematic selection of signal events. We perform a signal-to-background analysis to demonstrate the LHC prospects for charged Higgs discovery in the resulting channel $pp\\to t(\\bar{b})H^-\\to \\ell^\\pm\
Csorgo, T
2013-01-01
One of the highlights of 2012 in physics is related to two papers, published by the ATLAS and the CMS Collaborations, that announced the discovery of at least one new particle in pp collisions at CERN LHC. At least one of the properties of this new particle is found to be similar to that of the Higgs boson, the last and most difficult to find building block from the Standard Model of particle physics. Physics teachers are frequently approached by their media-educated students, who inquire about the properties of the Higgs boson, but physics teachers are rarely trained to teach this elusive aspect of particle physics in elementary, middle or junior high schools. In this paper I describe a card-game, that can be considered as a hands-on and easily accessible tool that allows interested teachers, students and also motivated lay-persons to play with the properties of the newly found Higgs-like particle. This new particle was detected through its decays to directly observable, final state particles. Many of these ...
Stephanie McClellan
2013-01-01
Before embarking on a successful career as a musician, Alan Parsons started out as a sound engineer - earning his first credit on The Beatles’ Abbey Road. Over the years, he has worked and collaborated with various artists, but 30 September 2013 marks a unique collaboration. For CERN’s ‘Bosons & More’ party, Alan Parsons Live Project will be sharing the stage with the Orchestre de la Suisse Romande. Having already visited CERN in 2011, Alan Parsons provides an insight into his views on science and his upcoming performance at the ‘Bosons & More’ event. Alan Parsons during his visit to CERN in August 2011. Since visiting CERN in 2011, how have your feelings towards the Organization developed? I was thrilled to hear about the recent discovery and how years of work had paid off. Together with my wife, Lisa, and my band, we were very privileged to come to CERN a couple of years ago, hav...
Search for a Higgs boson produced in association with a W boson at ATLAS
Energy Technology Data Exchange (ETDEWEB)
Ruckert, Benjamin
2009-11-23
The Large Hadron Collider at CERN the most modern proton-proton collider and data taking will start in 2009, with a centre-of-mass energy of {radical}(s) = 7 TeV. The ATLAS detector, which is one of two multi-purpose detectors at the Large Hadron Collider, is able to detect a Standard Model Higgs boson if it exists. This is one of the main tasks of the ATLAS experiment. This thesis deals with a Standard Model Higgs boson produced in association with a W boson. The Monte Carlo study is based on physics events generated at the nominal centre-of-mass energy of the Large Hadron Collider of {radical}(s) = 14 TeV. Large parts of this analysis have been done using the global Grid infrastructure of the Large Hadron Collider experiments. A mass range of the Higgs boson of m{sub H} = 130 - 190 GeV has been taken into account. In this mass range, the Higgs boson dominantly decays into a pair of W bosons, leading to initially three W bosons: WH{yields}WWW. Two orthogonal analysis channels have been investigated in detailed studies of the background properties. The first channel considers the leptonic decay of two W bosons, such that the leptons are of opposite charge. The third W boson then decays hadronically. The analysis is based on one-dimensional cuts, where the best cuts found are strict cuts on the transverse momenta of the leptons, a cut on the invariant mass of the jets, as well as a cut on the transverse jet momenta and the missing transverse energy. The second decay channel studied is dedicated to the leptonic decay of all three W bosons. Again, cuts on the transverse momenta of the leptons and the jets have been proven to be efficient, as well as the use of the spatial correlation of the decay products of the Higgs boson. The invariant mass of the leptons with opposite sign has been emerged as a very efficient cut to reject dominant diboson background contributions. The discovery reach of both channels separately as well as the combination has been calculated using
Search for a Higgs boson produced in association with a W boson at ATLAS
International Nuclear Information System (INIS)
The Large Hadron Collider at CERN the most modern proton-proton collider and data taking will start in 2009, with a centre-of-mass energy of √(s) = 7 TeV. The ATLAS detector, which is one of two multi-purpose detectors at the Large Hadron Collider, is able to detect a Standard Model Higgs boson if it exists. This is one of the main tasks of the ATLAS experiment. This thesis deals with a Standard Model Higgs boson produced in association with a W boson. The Monte Carlo study is based on physics events generated at the nominal centre-of-mass energy of the Large Hadron Collider of √(s) = 14 TeV. Large parts of this analysis have been done using the global Grid infrastructure of the Large Hadron Collider experiments. A mass range of the Higgs boson of mH = 130 - 190 GeV has been taken into account. In this mass range, the Higgs boson dominantly decays into a pair of W bosons, leading to initially three W bosons: WH→WWW. Two orthogonal analysis channels have been investigated in detailed studies of the background properties. The first channel considers the leptonic decay of two W bosons, such that the leptons are of opposite charge. The third W boson then decays hadronically. The analysis is based on one-dimensional cuts, where the best cuts found are strict cuts on the transverse momenta of the leptons, a cut on the invariant mass of the jets, as well as a cut on the transverse jet momenta and the missing transverse energy. The second decay channel studied is dedicated to the leptonic decay of all three W bosons. Again, cuts on the transverse momenta of the leptons and the jets have been proven to be efficient, as well as the use of the spatial correlation of the decay products of the Higgs boson. The invariant mass of the leptons with opposite sign has been emerged as a very efficient cut to reject dominant diboson background contributions. The discovery reach of both channels separately as well as the combination has been calculated using Bayesian methods. The
Directory of Open Access Journals (Sweden)
ChangJiang eXu
2014-01-01
Full Text Available When analyzing the data arising from exome or whole-genome sequencing studies, window-based tests, i.e. tests that jointly analyze all genetic data in a small genomic region, are very popular. However, power is known to be quite low for finding associations with phenotypes using these tests, and hence a variety of analytic strategies may be employed to potentially improve power. Using sequencing data from all of chromosome 3 in an interim release of data on 2,432 individuals from the UK10K project, we simulated phenotypes associated with rare genetic variation, and used the results to explore the window-based test power, and to ask two specific questions. Firstly, we asked whether there could be substantial benefits associated with incorporating information from external annotation on the genetic variants, and secondly we asked whether the false discovery rate (FDRs would be a useful metric for assessing significance. Although, as expected, there are benefits to using additional information (such as annotation when it is associated with causality, we confirmed the general pattern of low sensitivity and power for window-based tests. At least for our chosen example, even when power is high to detect some associations, many of the regions containing causal variants cannot be detected, despite using lax significance thresholds and optimal analytic methods. Furthermore, our estimated FDR values tended to be much smaller than the true FDRs. Long-range correlations between variants—due to linkage disequilibrium—likely explains some of this bias. A more sophisticated approach to using the annotation information may help the power, but many causal variants of realistic effect sizes may simply be undetectable, at least with this sample size. Perhaps annotation information could assist in distinguishing windows containing causal variants from windows that are merely correlated with causal variants.
Search for a charged Higgs boson in $\\tau\
AUTHOR|(INSPIRE)INSPIRE-00011001; Gallinaro, Michele
The Large Hadron Collider (LHC) started the first proton-proton collisions at a center-of-mass energy of 7 TeV in 2010. Soon thereafter, the experiments started collecting data and were able to rediscover the Standard Model (SM) in a few months, thanks to the very good understanding of the detectors, and their already precise calibrations. The LHC took data at $\\sqrt{s}=7$~TeV and 8~TeV in the years 2010-2011 and 2012, respectively: the peak of his intensive data taking has been, in 2012, the discovery, by the CMS and ATLAS experiment s, of a neutral boson with a mass of approximately 125\\unit{\\GeV}. The properties of the new boson are consistent with those predicted for the Standard Model (SM) Higgs boson, and models with an extended Higgs sector are constrained by the measured properties of the new boson: the discovery of another scalar boson, neutral or charged, would represent unambig uous evidence for the presence of physics beyond the SM. Charged Higgs bosons are predicted in models consisting of at...
Nonminimally coupled topological-defect boson stars: Static solutions
Reid, Graham D
2015-01-01
We consider spherically symmetric static composite structures consisting of a boson star and a global monopole, minimally or non-minimally coupled to the general relativistic gravitational field. In the non-minimally coupled case, Marunovic and Murkovic have shown that these objects, so-called boson D-stars, can be sufficiently gravitationally compact so as to potentially mimic black holes. Here, we present the results of an extensive numerical parameter space survey which reveals additional new and unexpected phenomenology in the model. In particular, focusing on families of boson D-stars which are parameterized by the central amplitude of the boson field, we find configurations for both the minimally and non-minimally coupled cases that contain one or more shells of bosonic matter located far from the origin. In parameter space, each shell spontaneously appears as one tunes through some critical central amplitude of the boson field. In some cases the shells apparently materialize at spatial infinity: in the...
International Nuclear Information System (INIS)
We study the discovery potential of the CERN LHC, Fermilab Tevatron and CERN LEP colliders in the search for the neutral CP-even Higgs boson of the MSSM which couples to the weak gauge bosons with a strength close to the standard model one and, hence, plays a relevant role in the mechanism of electroweak symmetry breaking. We place special emphasis on the radiative effects which influence the discovery reach of these colliders. We concentrate on the Vb(ovr b) channel, with V=Z or W, and on the channels with diphoton final states, which are the dominant ones for the search for a light standard model Higgs boson at LEP or Tevatron and LHC, respectively. By analyzing the parameters of the MSSM for which the searches become difficult at one or more of these three colliders, we demonstrate their complementarity in the search for a light Higgs boson which plays a relevant role in the mechanism of electroweak symmetry breaking
Pimenta, Jean Jûnio Mendes; Belussi, Lucas Francisco Bosso; Natti, Érica Regina Takano; Natti, Paulo Laerte
2013-01-01
The Higgs boson was predicted in 1964 by British physicist Peter Higgs. The Higgs is the key to explain the origin of the mass of other elementary particles of Nature. However, only with the coming into operation of the LHC, in 2008, there were technological conditions to search for the Higgs boson. Recently, a major international effort conducted at CERN, by means of ATLAS and CMS experiments, has enabled the observation of a new bosonic particle in the region of 125 GeVs. In this paper, by ...
Photoproduction of leptophobic bosons
Fanelli, Cristiano
2016-01-01
We propose a search for photoproduction of leptophobic bosons that couple to quarks at the GlueX experiment at Jefferson Lab. We study in detail a new gauge boson that couples to baryon number $B$, and estimate that $\\gamma p \\to p B$ will provide the best sensitivity for $B$ masses above 0.5 GeV. This search will also provide sensitivity to other proposed dark-sector states that couple to quarks. Finally, our results motivate a similar search for $B$ boson electroproduction at the CLAS experiment.
Search for a Higgs-like boson decaying into bottom quarks in the Z(IIH channel
Directory of Open Access Journals (Sweden)
Eller Philipp
2013-11-01
Full Text Available After the discovery of a Higgs-like Boson with a mass close to 125 GeV at the LHC in summer 2012, we are showing the update on the analysis of the VH cannel. In this channel the Higgs-like Boson is produced in association with a vector boson and decaying into b quarks. We present the updated results on the full 2011 and 2012 7+8 TeV dataset. This poster will focus on one of the tree modes that are combined in this analysis, where the associated vector boson is a Z boson that is decaying leptonically into two electrons or muons, respectively.
Search for a Higgs-like boson decaying into bottom quarks in the Z(II)H channel
International Nuclear Information System (INIS)
After the discovery of a Higgs-like Boson with a mass close to 125 GeV at the LHC in summer 2012, we are showing the update on the analysis of the VH cannel. In this channel the Higgs-like Boson is produced in association with a vector boson and decaying into b quarks. We present the updated results on the full 2011 and 2012 7+8 TeV dataset. This poster will focus on one of the tree modes that are combined in this analysis, where the associated vector boson is a Z boson that is decaying leptonically into two electrons or muons, respectively. (authors)
Determination of the Higgs boson spin at ATLAS
Sanchez Pineda, A; The ATLAS collaboration
2013-01-01
In 2012 ATLAS and CMS collaborations announced the discovery of a new resonance in the search for the Standard Model (SM) Higgs boson. The next step is the experimental determination of its properties in order to understand if it’s the SM Higgs Boson or “someone” beyond. This presentation will resume the state of the art of the ATLAS studies of the spin/parity (JP) quantum numbers of the new boson, due to its production and decay nature, is a neutral boson. To distinguishing between different hypotheses, including that from the Standard Model, ATLAS relies on discriminant observables chosen to be sensitive to the spin and parity of the signal for each channel considered, using data recorded in 2011 and 2012.
Direct search for the standard model Higgs boson
Janot, Patrick
2002-01-01
For twelve years, LEP revolutionized the knowledge of electroweak symmetry breaking within the standard model, and the direct discovery of the Higgs boson would have been the crowning achievement. Searches at the Z resonance and above the W/sup +/W/sup -/ threshold allowed an unambiguous lower limit on the mass of the standard model Higgs boson to set be at 114.1 GeV.c/sup -2/. After years of efforts to push the LEP performance far beyond the design limits, hints of what could be the first signs of the existence of a 115 GeV-c/sup -2/ Higgs boson appeared in June 2000, were confirmed in September, and were then confirmed again in November. An additional six-month period of LEP operation was enough to provide a definite answer, with an opportunity to make a fundamental discovery of prime importance. (37 refs).
Arkhipov, Alex
2011-01-01
We motivate and prove a version of the birthday paradox for $k$ identical bosons in $n$ possible modes. If the bosons are in the uniform mixed state, also called the maximally mixed quantum state, then we need $k \\sim \\sqrt{n}$ bosons to expect two in the same state, which is smaller by a factor of $\\sqrt{2}$ than in the case of distinguishable objects (boltzmannons). While the core result is elementary, we generalize the hypothesis and strengthen the conclusion in several ways. One side result is that boltzmannons with a randomly chosen multinomial distribution have the same birthday statistics as bosons. This last result is interesting as a quantum proof of a classical probability theorem; we also give a classical proof.
International Nuclear Information System (INIS)
We report on the evaluation of the performance of a Mediterranean very large volume neutrino telescope. We present results of our studies concerning the capability of the telescope in detecting/discovering Galactic (steady point sources) and extragalactic, transient (Gamma Ray Bursts) high energy neutrino sources as well as measuring ultra high energy diffuse neutrino fluxes. The neutrino effective area and angular resolution are presented as a function of the neutrino energy, and the background event rate (atmospheric neutrinos and muons) is estimated. The discovery potential of the neutrino telescope is evaluated and the experimental time required for a significant discovery of potential neutrino emitters (known from their gamma ray emission, assumedly produced by hadronic interactions) is estimated. For the simulation we use the HOU Reconstruction and Simulation (HOURS) software package
Barkhofen, Sonja; Bartley, Tim J.; Sansoni, Linda; Kruse, Regina; Hamilton, Craig S.; Jex, Igor; Silberhorn, Christine
2016-01-01
Sampling the distribution of bosons that have undergone a random unitary evolution is strongly believed to be a computationally hard problem. Key to outperforming classical simulations of this task is to increase both the number of input photons and the size of the network. We propose driven boson sampling, in which photons are input within the network itself, as a means to approach this goal. When using heralded single-photon sources based on parametric down-conversion, this approach offers ...
Search for the Higgs Boson in the Channel H->ZZ*->4l with the ATLAS Detector
Rebuzzi, D; The ATLAS collaboration
2009-01-01
The decay channel H->ZZ*->4l provides a clean signature for the Higgs boson in the mass range between ~120 GeV and 2MZ, above which the "gold-plated" channel with two real Z bosons in the final state opens up. The signal cross section is several orders of magnitude smaller than those for the backgrounds, therefore a thorough understanding of the multi-lepton processes is needed to obtain a high background rejection. Crucial for this channel is also a very good knowledge of the trigger and detector response for lepton identification and reconstruction. The observability of the signal on top of the reducible tt, Zbb and of the irreducible ZZz backgrounds with the ATLAS Detector is discussed in the following, with particular emphasis on lepton reconstruction. The ATLAS discovery potential for the H->4l, including the most realistic and up-to-date description of the detector performance, is presented.
Phenomenological Study of W′ Boson Decaying to Muon and Missing Transverse Energy at 14 TeV
International Nuclear Information System (INIS)
Many possible extensions of the Standard Model (SM) are predicted by theories. A possible abstracted extension of the SM is the so-called Sequentail Standard Model (SSM). The SSM model predicts signature of new charged gauge boson W′. In this paper, the discovery potential of new heavy charged gauge boson (W′) decaying to a muon and a neutrino at center of mass energy 14 TeV has been studied. An assumption has been made that the early data of the second run of the Large Hadron Collider (LHC) correspond to an integrated luminosity of 300 fb-1. The Monte Carlo (MC) signal samples are generated with the multipurpose event generator Pythia 6, while the background samples are generated with the matrix element generator Mad Graph 5 followed by hadronization and parton showering by using Pythia 8 and then we used Delphes for fast detector simulation
Carena, M S; Herfurth, F; Ames, F; Audi, G; Beck, D; Blaum, K; Bollen, G; Kellerbauer, A G; Kluge, H J; Kuckein, M; Lunney, M D; Moore, R B; Oinonen, M; Rodríguez, D; Sauvan, E; Scheidenberger, C
2003-01-01
Precision electroweak data presently-favors a weakly-coupled Higgs sector as the mechanism responsible for electroweak symmetry breaking. Low-energy supersymmetry provides a natural framework for weakly-coupled elementary scalars. In this review, we summarize the theoretical properties of the Standard Model (SM) Higgs boson and the Higgs sector of the minimal super-symmetric extension of the Standard Model (MSSM). We then survey the phenomenology of the SM and MSSM Higgs bosons at the Tevatron, LHC and a future e**+e**- linear collider. We focus on the Higgs discovery potential of present and future colliders and stress the importance of precision measurements of Higgs boson properties. 459 Refs.31 The Penning trap mass spectrometer ISOLTRAP is a facility for high- precision mass measurements of short-lived radioactive nuclei installed at ISOLDE/CERN in Geneva. More than 200 masses have been measured with relative uncertainties of 1 multiplied by 10**-**7 or even close to 1 multiplied by 10**-**8 in special c...
Bosonic behavior of entangled fermions
International Nuclear Information System (INIS)
Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle remains irrelevant. The bosonic character of the composite is intimately linked to the entanglement of the fermions: Large entanglement implies good bosonic properties. The deviation from perfect bosonic behavior manifests itself in the statistical properties of the composites and in their collective interference. As a consequence, the counting statistics exhibited by composites allow one to infer the form of the two-fermion wave-function. Bosonic behavior can thus be used as a probe for the underlying structure of composite particles without directly accessing their constituents.
Search for Charged Higgs Bosons with the ATLAS Detector at the LHC
Czodrowski, Patrick
2013-07-30
The discovery of a charged Higgs boson, $H^+$, would be an unambiguous evidence for physics beyond the Standard Model. In this thesis a search for the $H^+$, with the ATLAS experiment at the Large Hadron Collider, LHC, at CERN based on data taken in 2011, are described. A re-analysis of the charged Higgs boson search, utilising the ratio-method, was performed, which greatly enhanced the sensitivity compared to the traditional direct search approach. Light charged Higgs bosons, with a mass lower than the top quark mass, can be produced in top quark decays. Due to the large production cross-section of top quark pairs the light charged Higgs bosons are accessible with early LHC data, in contrast to charged Higgs bosons heavier than the top quark mass. For light charged Higgs bosons the decay via $H^\\pm \\to \\tau^\\pm \
Kiiskinen, A P
2004-01-01
This thesis describes direct searches for pair production of charged Higgs bosons performed in the data collected by the DELPHI detector at the LEP collider at CERN. In addition, the possibilities to discover and study heavy charged Higgs bosons at possible future high-energy linear colliders are presented. The existence of charged Higgs bosons is predicted by many extensions of the Standard Model. A possible discovery of these particles would be a solid proof for physics beyond the Standard Model. Discovery of charged Higgs bosons, and measurement of their properties, would also provide useful information about the structure of the more general theory. New analysis methods were developed for the searches performed at LEP. A large, previously unexplored, mass range for cover but no evidence for the existence of the charged Higgs bosons was found. This allowed setting new lower mass limits for the charged Higgs boson within the framework of general two Higgs doublet models. Results have been interpreted and pr...
Directory of Open Access Journals (Sweden)
Kooren Joel A
2011-09-01
Full Text Available Abstract Introduction Early diagnosis of Oral Squamous Cell Carcinoma (OSCC increases the survival rate of oral cancer. For early diagnosis, molecular biomarkers contained in samples collected non-invasively and directly from at-risk oral premalignant lesions (OPMLs would be ideal. Methods In this pilot study we evaluated the potential of a novel method using commercial PerioPaper absorbent strips for non-invasive collection of oral lesion exudate material coupled with mass spectrometry-based proteomics for oral cancer biomarker discovery. Results Our evaluation focused on three core issues. First, using an "on-strip" processing method, we found that protein can be isolated from exudate samples in amounts compatible with large-scale mass spectrometry-based proteomic analysis. Second, we found that the OPML exudate proteome was distinct from that of whole saliva, while being similar to the OPML epithelial cell proteome, demonstrating the fidelity of our exudate collection method. Third, in a proof-of-principle study, we identified numerous, inflammation-associated proteins showing an expected increase in abundance in OPML exudates compared to healthy oral tissue exudates. These results demonstrate the feasibility of identifying differentially abundant proteins from exudate samples, which is essential for biomarker discovery studies. Conclusions Collectively, our findings demonstrate that our exudate collection method coupled with mass spectrometry-based proteomics has great potential for transforming OSCC biomarker discovery and clinical diagnostics assay development.
Arbesman, Samuel; Laughlin, Gregory
2010-01-01
Background The search for a habitable extrasolar planet has long interested scientists, but only recently have the tools become available to search for such planets. In the past decades, the number of known extrasolar planets has ballooned into the hundreds, and with it, the expectation that the discovery of the first Earth-like extrasolar planet is not far off. Methodology/Principal Findings Here, we develop a novel metric of habitability for discovered planets and use this to arrive at a pr...
Scattering problem for four-boson system
International Nuclear Information System (INIS)
The s-wave phase shift of boson-triboson scattering has been obtained by solving the Faddeev-Osborn equation in the exact approach based on rigorous Faddeev theory. The Schmidt expansion theorem is used to express the 3+1- and 2+2-subamplitudes at energies in the continuous spectrum region as an infinite series of separable terms. Employing the pole term decomposition for these subamplitudes expressed in terms of the Schmidt expansion we can define, in conformity with the Faddeev residue prescription, respective four-nucleon amplitudes that describe elastic/rearrangement, partial breakup and full breakup scattering processes. Acquired simultaneous equations of these amplitudes take the form of multichannel two-particle Lippmann-Schwinger type, which we call Faddeev-Osborn equation. Assuming as an s-wave spin-independent, rank one separable potential of the Yamaguchi type for the two-particle interaction, are derived the Faddeev-Osborn equation for the boson-triboson elastic scattering. To treat singularities appeared in our equation, the numerical calculation is performed in the framework of the complex-valued analysis by introducing contour rotation method. The boson-triboson elastic scattering amplitude for L=0 state of a four-boson system is obtained numerically in the incident boson laboratory energy region of 0.01-24.0 Mev, including only 1=0 state for the 3+1-subamplitude. The results of the phase shift obtained from the amplitudes are plotted as dots in Fig. 1. (author)
Charged Higgs boson in the W± Higgs channel at the Large Hadron Collider
Directory of Open Access Journals (Sweden)
Rikard Enberg
2015-04-01
Full Text Available In light of the recent discovery of a neutral Higgs boson, Hobs, with a mass near 125 GeV, we reassess the LHC discovery potential of a charged Higgs boson, H±, in the W±Hobs decay channel. This decay channel can be particularly important for a H± heavier than the top quark, when it is produced through the pp→tH± process. The knowledge of the mass of Hobs provides an additional handle in the kinematic selection when reconstructing a Breit–Wigner resonance in the Hobs→bb¯ decay channel. We consider some extensions of the Standard Model Higgs sector, with and without supersymmetry, and perform a dedicated signal-to-background analysis to test the scope of this channel for the LHC running at the design energy (14 TeV, for 300 fb−1 (standard and 3000 fb−1 (high integrated luminosities. We find that, while this channel does not show much promise for a supersymmetric H± state, significant portions of the parameter spaces of several two-Higgs doublet models are testable.
HNC variational calculations of boson matter
International Nuclear Information System (INIS)
A simple and reliable numerical technique is given for determining the two-body distribution function which minimizes the HNC energy of boson matter. Numerical results are presented for the neutron matter homework problem and the 4He Lennard-Jones potential. The resulting distribution function is found to have proper asymptotic behaviour and yields reasonable binding energies. (Auth.)
Search for doubly charged Higgs bosons through vector boson fusion at the LHC and beyond
Bambhaniya, G.; Chakrabortty, J.; Gluza, J.; Jeliński, T.; Szafron, R.
2015-07-01
Production and decays of doubly charged Higgs bosons at the LHC and future hadron colliders triggered by a vector boson fusion mechanism are discussed in the context of the minimal left-right symmetric model. Our analysis is based on the Higgs boson mass spectrum compatible with available constraints which include flavor changing neutral current (FCNC) effects and vacuum stability of the scalar potential. Though the parity breaking scale vR is large (˜ few TeV) and scalar masses which contribute to FCNC effects are even larger, a consistent Higgs boson mass spectrum still allows us to keep doubly charged scalar masses below 1 TeV which is an interesting situation for LHC and future circular collider (FCC). We have shown that the allowed Higgs boson mass spectrum constrains the splittings (MH1±±-MH1± ), closing the possibility of H1±±→W1±H1± decays. Assuming that doubly charged Higgs bosons decay predominantly into a pair of same-sign charged leptons through the process p p →H1/2 ±±H1/2 ∓∓j j →ℓ±ℓ±ℓ∓ℓ∓j j , we find that for the LHC operating at √{s }=14 TeV with an integrated luminosity at the level of 3000 fb-1 (HL-LHC), there is practically no chance to detect such particles at the reasonable significance level through this channel. However, at 33 TeV HE-LHC and (or) 100 TeV FCC-hh, a wide region opens up for exploring the doubly charged Higgs boson mass spectrum. In FCC-hh, the doubly charged Higgs bosons mass up to 1 TeV can be easily probed.
Marino, Eduardo
The electron, discovered by Thomson by the end of the nineteenth century, was the first experimentally observed particle. The Weyl fermion, though theoretically predicted since a long time, was observed in a condensed matter environment in an experiment reported only a few weeks ago. Is there any linking thread connecting the first and the last observed fermion (quasi)particles? The answer is positive. By generalizing the method known as bosonization, the first time in its full complete form, for a spacetime with 3+1 dimensions, we are able to show that both electrons and Weyl fermions can be expressed in terms of the same boson field, namely the Kalb-Ramond anti-symmetric tensor gauge field. The bosonized form of the Weyl chiral currents lead to the angle-dependent magneto-conductance behavior observed in these systems.
Liebling, Steven L
2012-01-01
The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.
Directory of Open Access Journals (Sweden)
Steven L. Liebling
2012-05-01
Full Text Available The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s, John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called geons, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name boson stars. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single Killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.
Tsekov, R
2016-01-01
Thermodynamically, bosons and fermions differ by their statistics only. A general entropy functional is proposed by superposition of entropic terms, typical for different quantum gases. The statistical properties of the corresponding Janus particles are derived by variation of the weight of the boson/fermion fraction. It is shown that di-bosons and anti-fermions separate in gas and liquid phases, while three-phase equilibrium appears for poly-boson/fermion Janus particles.
International Nuclear Information System (INIS)
We study the phenomenology of Higgs bosons close to 126 GeV within the scale invariant unconstrained Next-to-Minimal Supersymmetric Standard Model (NMSSM), focusing on the regions of parameter space favoured by low fine-tuning considerations, namely stop masses of order 400 GeV to 1 TeV and an effective μ parameter between 100–200 GeV, with large (but perturbative) λ and low tanβ=2–4. We perform scans over the above parameter space, focusing on the observable Higgs cross sections into γγ, WW, ZZ, bb, ττ final states, and study the correlations between these observables. We show that the γγ signal strength may be enhanced up to a factor of about two not only due to the effect of singlet–doublet mixing, which occurs more often when the 126 GeV Higgs boson is the next-to-lightest CP-even one, but also due to light stops (and to a lesser extent light chargino and charged Higgs loops). There may be also smaller enhancements in the Higgs decay channels into WW, ZZ, correlated with the γγ enhancement. However there is no such correlation observed involving the Higgs decay channels into bb, ττ. The requirement of having perturbative couplings up to the GUT scale favours the interpretation of the 126 GeV Higgs boson as being the second lightest NMSSM CP-even state, which can decay into pairs of lighter neutralinos, CP-even or CP-odd Higgs bosons, leading to characteristic signatures of the NMSSM. In a non-negligible part of the parameter range the increase in the γγ rate is due to the superposition of rates from nearly degenerate Higgs bosons. Resolving these Higgs bosons would rule out the Standard Model, and provide evidence for the NMSSM
Search for the Standard Model Higgs boson in the $H\\rightarrow W^{+}W^{-}\\rightarrow\\ell^{+}\
Schmidt, Evelyn
2013-06-06
Modern particle physics research is dedicated to study the fundamental constituents of matter and their interactions. Scientific research findings on both theoretical and experimental sides during the past decades have been condensed in the Standard Model of particle physics. In this model, the interactions between fundamental particles are described by gauge fields and the exchange of corresponding gauge bosons. The Standard Model contains several such bosons, for example the massive and charged W bosons and a neutral Z boson, that have been observed experimentally. The simplest and most popular implementation of electroweak symmetry breaking to attribute mass to the W and Z bosons is the Higgs mechanism. This mechanism implies the existence of one additional particle, the Higgs boson, that is the only remaining particle of the Standard Model to be established experimentally. In July 2012, the discovery of a new neutral boson with a measured mass of about 126 GeV was announced by the ATLAS and CMS collaborat...
Anomalous gauge boson interactions
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We discuss the direct measurement of the trilinear vector boson couplings in present and future collider experiments. The major goals of such experiments will be the confirmation of the Standard Model (SM) predictions and the search for signals of new physics. We review our current theoretical understanding of anomalous trilinear gauge-boson self interactions. If the energy scale of the new physics is ∼ 1 TeV, these low energy anomalous couplings are expected to be no larger than Ο(10-2). Constraints from high precision measurements at LEP and low energy charged and neutral current processes are critically reviewed
International Nuclear Information System (INIS)
This is the summary report of the Higgs Boson Working Group. We discuss a variety of search techniques for a Higgs boson which is lighter than the Z. The processes K → πH, η prime → ηH,Υ → Hγ and e+e- → ZH are examined with particular attention paid to theoretical uncertainties in the calculations. We also briefly examine new features of Higgs phenomenology in a model which contains Higgs triplets as well as the usual doublet of scalar fields. 33 refs., 6 figs., 1 tab
Nonexotic Neutral Gauge Bosons
Appelquist, Thomas; Dobrescu, Bogdan A.; Hopper, Adam R.
2002-01-01
We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may be described by a gauge theory in which the Abelian gauge groups are the usual hypercharge along with another U(1) component in a kinetic-diagonal basis. Assuming that the observed quarks and leptons have generation-independent U(1) charges, and that no new...
International Nuclear Information System (INIS)
This paper is the summary report of the Higgs Boson Working Group. The authors discuss a variety of search techniques for a Higgs boson which is lighter than the Z. The processes K → πH, η' → ηH, Υ → Hγ and e+e- → ZH are examined with particular attention paid to theoretical uncertainties in the calculations. The authors also briefly examine new features of Higgs phenomenology in a model which contains Higgs triplets as well as the usual doublet of scalar fields
Bosonic variables in nuclear matters
International Nuclear Information System (INIS)
It is shown that the boson theoretical interpretation of nuclear forces nessecitates the introduction of bosonic variables within the state function of nuclear matter. In this framework the 2-boson exchange plays a decisive role and calls for the introduction of special selfenergy diagrams. This generalized scheme is discussed with the help of a solvable field theoretical model. (orig.)
Intermediate mass Higgs boson(s)
International Nuclear Information System (INIS)
Finding and understanding the spectrum of scalar bosons is the central problem of particle physics today. Considerable work has been done to learn how to study Standard Model heavy and obese Higgs bosons; simulations including the problems induced by standard model backgrounds are underway, and some results are reported elsewhere in these proceedings. The mass region MH Z/2 will be covered at SLC and LEP. LEPII will be able to extend this range to about 85 GeV. Above MH > 2MZ the search is easy for a Standard Model H degree at the SSC, though not so simple for the neutral scalars of a supersymmetric theory. The intermediate region, MZ/2 ≤ MH ≤ 2MZ is one of the most difficult mass regions to study, and it is the subject of this report. The authors concentrate on a neutral Standard Model scalar to be specific. The lightest scalar of a supersymmetric theory behaves very much like a Standard Model scalar for most ranges of parameters, so the results generally apply to that case as well, and for any form the scalar spectrum might take our results indicate how the analysis might go. Ultimately, to fully understand spontaneous symmetry breaking and the origin of mass, it will be necessary to find any intermediate mass scalar and to know in what mass ranges no scalars exist. Their analysis is only in progress, and their results reported here must be regarded as tentative
From neutral currents to vector bosons
International Nuclear Information System (INIS)
The history of the postulated electroweak interactions, the unified theory of electromagnetic and weak interactions is reviewed. The theoretical basis of the unified description of quantum electrodynamics (QED) and Fermi weak interaction theory as well as the first experimental facts showing the existence of symmetry breaking in QED are described. The Weinberg-Salam unified theory of electroweak interaction predicted the weak neutral currents which were first detected in 1973 and later honoured with Nobel Prize, and it predicted also the existence of intermediate vector bosons W and Z detected in CERN in 1983. The experimental problems of the discovery of W and Z involving particle detection and identification methods are discussed in detail. Detectors and data acquisition methods used in the CERN experiments are described. The importance of the new discovery is emphasized. (D.Gy.)
Higgs boson: the winner takes it all?
Antonella Del Rosso
2015-01-01
Since its discovery in 2012, the Higgs boson has been in the spotlight for both experimentalists and theorists. In addition to its confirmed role in the mass mechanism, recent papers have discussed its possible role in the inflation of the universe and in the matter-antimatter imbalance. Can a single particle be responsible for everything? “Since 2012 we have known that the Higgs boson exists, but its inner properties are yet to be completely uncovered,” says Gian Giudice, a member of the CERN Theory Unit. “Precise measurements of its decay modes are still ongoing and the LHC Run 2 will be essential to understand the nature of this particle at a deeper level.” What we know is that this boson is not “yet another particle” among the hundreds that we deal with every day in physics labs. In agreement with the Standard Model theory, the recent experimental data confirms that the particle discovered by the CERN experiments is the key pa...
Discovering Higgs Bosons of the MSSM using Jet Substructure
Energy Technology Data Exchange (ETDEWEB)
Kribs, Graham D.; Martin, Adam; Roy, Tuhin S.; Spannowsky, Michael
2010-06-01
We present a qualitatively new approach to discover Higgs bosons of the MSSM at the LHC using jet substructure techniques applied to boosted Higgs decays. These techniques are ideally suited to the MSSM, since the lightest Higgs boson overwhelmingly decays to b{bar b} throughout the entire parameter space, while the heavier neutral Higgs bosons, if light enough to be produced in a cascade, also predominantly decay to b{bar b}. The Higgs production we consider arises from superpartner production where superpartners cascade decay into Higgs bosons. We study this mode of Higgs production for several superpartner hierarchies: m{sub {tilde q}},m{sub {tilde g}} > m{sub {tilde W}},{sub {tilde B}} > m{sub h} + {mu}; m{tilde q};m{sub {tilde q}},m{sub {tilde g}} > m{sub {tilde W}},{sub {tilde B}} > m {sub h,H,A} + {mu}; and m{sub {tilde q}},m{sub {tilde g}} > m{sub {tilde W}} > m{sub h} + {mu} with m{sub {tilde B}} {approx} {mu}. In these cascades, the Higgs bosons are boosted, with pT > 200 GeV a large fraction of the time. Since Higgs bosons appear in cascades originating from squarks and/or gluinos, the cross section for events with at least one Higgs boson can be the same order as squark/gluino production. Given 10 fb{sup -1} of 14 TeV LHC data, with m{sub {tilde q}} {approx}< 1 TeV, and one of the above superpartner mass hierarchies, our estimate of S{radical} B of the Higgs signal is sufficiently high that the b{bar b} mode can become the discovery mode of the lightest Higgs boson of the MSSM.
Mixtures of Bosonic and Fermionic Atoms in Optical Lattices
Albus, Alexander; Illuminati, Fabrizio; Eisert, Jens
2003-01-01
We discuss the theory of mixtures of Bosonic and Fermionic atoms in periodic potentials at zero temperature. We derive a general Bose--Fermi Hubbard Hamiltonian in a one--dimensional optical lattice with a superimposed harmonic trapping potential. We study the conditions for linear stability of the mixture and derive a mean field criterion for the onset of a Bosonic superfluid transition. We investigate the ground state properties of the mixture in the Gutzwiller formulation of mean field the...
Jora, Renata
2009-01-01
We propose an electroweak model based on the identification of the Higgs with the dilaton. We show that it is possible in this context to have a massless Higgs boson at tree and one loop levels without contradicting the main experimental and theoretical constraints.
AUTHOR|(CDS)2077480; Müller, Katharina; Anderson, Jonathan
In this thesis several measurements of the $Z$ boson production cross section in the LHCb detector are presented. After an introduction with the description of the underlying theory; the detector and the properties of the collisions the machine provided to us in LHC run I in Chapter 1, in Chapter 2 the details of the $Z$ reconstruction in the $Z\\rightarrow\\mu^+\\mu^-$ final state is discussed. In Chapter 3 jets are added to the $Z$ bosons. Several aspects of jet reconstruction are presented and a cross section measurement for the associated production of $Z$ bosons with jets at $\\sqrt{s}=7$ TeV is presented for two transverse momentum thresholds of the jets. In Chapter 4 the capability of the LHCb detector to reconstruct charmed mesons is used to establish a $ZD^{0}$ and a $ZD^{+}$ signal and to measure the total cross section. In Chapter 5 the cross section of inclusive $Z$ boson production is measured at a low statistics sample of $3.3~\\text{pb}^{-1}$ at $\\sqrt{s}=2.76$ TeV.
Standard electroweak interactions and Higgs bosons
Energy Technology Data Exchange (ETDEWEB)
Cox, B.; Gilman, F.J.
1984-09-01
In the standard model, only one basic component remains to be found: the Higgs boson. The specifics of Higgs boson production and detection, with decay to t anti t and a particular t quark mass range in mind, have not been examined in detail. As such, the working group on Standard Electroweak Interactions and Higgs Bosons at this meeting decided to concentrate on Higgs boson production and detection at SSC energies in the particular case where the Higgs mass is in the range so as to make t anti t quark-antiquark pairs the dominant decay mode. The study of this case, that of the so-called intermediate mass Higgs, had already been launched in the Berkeley PSSC Workshop on Electroweak Symmetry Breaking, and was continued and extended here. The problems of t quark jet identification and detection efficiency and the manner of rejection of background (especially from b quark jets) with realistic detectors then occupied much of the attention of the group. The subject of making precise measurements of parameters in the standard model at SSC energies is briefly examined. Then we delve into the Higgs sector, with an introduction to the neutral Higgs of the standard model together with its production cross-sections in various processes and the corresponding potential backgrounds. A similar, though briefer, discussion for a charged Higgs boson (outside the Standard Model) follows. The heart of the work on identifying and reconstructing the t and then the Higgs boson in the face of backgrounds is discussed. The problems with semileptonic decays, low energy jet fragments, mass resolution, and b-t discrimination all come to the fore. We have tried to make a serious step here towards a realistic assessment of the problems entailed in pulling a signal out of the background, including a rough simulation of calorimeter-detector properties. 25 references.
The Higgs boson saga - Hundred years of particles, the Higgs boson, and after?
International Nuclear Information System (INIS)
A first article recalls the history of the theoretical conception and discovery of particles since the beginning of the twentieth century. It outlines that particles like neutrino, antiproton or quark have been foreseen by theoreticians before a clue of their existence has been experimentally observed. These theories and experiments are based on the standard model which describes weak and strong interactions within a coherent set, and this model is confirmed by the recent evidence of a particle which could be the Higgs boson. A second article discusses this last issue (was it really the Higgs boson?), the work to be done to check this, and also the numerous issues associated with this particle which are now to be addressed, for example the nature of dark matter
Bosonic Decays of Charged Higgs Bosons in a 2HDM Type-I
Arhrib, Abdesslam; Moretti, Stefano
2016-01-01
In this study, we focus on the bosonic decays of light charged Higgs bosons in the 2-Higgs Doublet Model (2HDM) Type-I. We quantify the Branching Ratios (BRs) of the $H^\\pm \\to W^\\pm h$ and $H^\\pm\\to W^\\pm A$ channels and show that they could be substantial over several areas of the parameter space of the 2HDM Type-I that are still allowed by Large Hadron Collider (LHC) and other experimental data as well as theoretical constraints. We suggest that $H^\\pm \\to W^\\pm h$ and/or $H^\\pm \\to W^\\pm A$ could be used as a feasible discovery channel alternative to $H^\\pm \\to \\tau\
Higgs boson masses in supersymmetric models
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Imposing supersymmetry on a Higgs potential constrains the parameters that define the potential. In supersymmetric extensions to the stranded model containing only Higgs SU(2)L doublets there exist Higgs boson mass sum rules and bounds on the Higgs masses at tree level. The prescription for renormalizing these sum rules is derived. An explicit calculation is performed in the minimal supersymmetric extension to the standard model (MSSM). In this model at tree level the mass sum rule is MH2 + Mh2 = MA2 + MZ2. The results indicate that large corrections to the sum rules may arise from heavy matter fields, e.g. a heavy top quark. Squarks significantly heavier than their fermionic partners contribute large contributions when mixing occurs in the squark sector. These large corrections result from squark-Higgs couplings that become large in this limit. Contributions to individual Higgs boson masses that are quadratic in the squark masses cancel in the sum rule. Thus the naturalness constraint on Higgs boson masses is hidden in the combination of Higgs boson masses that comprise the sum rule. 39 refs., 13 figs
Mixtures of bosonic and fermionic atoms in optical lattices
International Nuclear Information System (INIS)
We discuss the theory of mixtures of bosonic and fermionic atoms in periodic potentials at zero temperature. We derive a general Bose-Fermi Hubbard Hamiltonian in a one-dimensional optical lattice with a superimposed harmonic trapping potential. We study the conditions for linear stability of the mixture and derive a mean-field criterion for the onset of a bosonic superfluid transition. We investigate the ground-state properties of the mixture in the Gutzwiller formulation of mean-field theory, and present numerical studies of finite systems. The bosonic and fermionic density distributions and the onset of quantum phase transitions to demixing and to a bosonic Mott-insulator are studied as a function of the lattice potential strength. The existence is predicted of a disordered phase for mixtures loaded in very deep lattices. Such a disordered phase possessing many degenerate or quasidegenerate ground states is related to a breaking of the mirror symmetry in the lattice
HIGGS BOSON PRODUCTION IN ASSOCIATION WITH BOTTOM QUARKS
International Nuclear Information System (INIS)
In the Standard Model, the coupling of the Higgs boson to b quarks is weak, leading to small cross sections for producing a Higgs boson in association with b quarks. However, Higgs bosons with enhanced couplings to b quarks, such as occur in supersymmetric models for large values of tan β, will be copiously produced at both the Tevatron and the LHC in association with b quarks which will be an important discovery channel. We investigate the connections between the production channels, bg → bh and gg → b(bar b)h, at next-to-leading order (NLO) in perturbative QCD and present results for the case with two high-pT b jets and with one high-pT b jet at both the Tevatron and the LHC. Finally, the total cross sections without cuts are compared between gg → b(bar b)h at NLO and b(bar b) → h at NNLO
International Nuclear Information System (INIS)
Circle contact lenses, also known as color contact lenses and big eye contact lenses, are a type of cosmetic contact lens. It is not generally known that a circle contact lens usually contains iron oxide and other metals, which means their use during magnetic resonance imaging (MRI) is a potential hazard. We present a rare case of incidental discovery of circle contact lenses by MRI and MRI images of circle lenses in vitro. Circle contact lenses usually contain iron oxide, which is a known source of susceptibility artifact on MRI. Not only radiologists and radiographers but also referring physicians should be familiar with the imaging findings and potential risk of scanning circle contact lenses by MRI
International Nuclear Information System (INIS)
The only particle of the Standard Model that has not yet been discovered is the Higgs boson, which explains the origin of the masses of elementary particles. In the Minimal Supersymmetric extension to the Standard Model (MSSM), the Higgs sector consists of five bosons, two of which are charged. The search for a charged Higgs boson in the gg → t-bar bH+(H+ → tb-bar) channel, is the main topic of this analysis. We present an analysis that uses a likelihood function to resolve combinatorial possibilities while reconstructing the charged Higgs boson, and the b-tagging to suppress the tt-bar + jets background. We also present the difficulties due to the combinatorial background reducing the discovery potential of this channel. The presence of 4 b quarks in the final state that we are looking for, makes the b-tagging an important tool for the analysis. Therefore, a part of this work is dedicated to the study of b-tagging. We present in the context of the preparation for the first data, several studies dedicated to the optimisation and the understanding of the b-tagging performance. We also present the commissioning of a simple tagger (JetProb) to be used with first data analysis. (author)
International Nuclear Information System (INIS)
The physics program of the ATLAS experiment at the Large Hadron Collider (CERN) covers a wide area going from the search for a Standard Model Higgs boson to the search for new physics (supersymmetry, extra-dimensions...). This thesis focuses on two main axes: First, some studies on the liquid argon calorimeter electronics are presented. Studies related to the search for the Standard Model Higgs boson in the H →γγ decay channel (which is one of the most promising discovery channels in the low mass region, between the LEP limit mH > 144.4 GeV and 150 GeV) are also detailed. In particular the reconstruction of photons and the use of photons conversion into electron-positron pair are detailed. The aim of these studies is to increase the discovery potential of the Higgs boson. Aspects related to the validation of the fast simulation package of the ATLAS experiment are also discussed: The performances of the photon reconstruction (for both unconverted and converted photons) as well as the ability to reproduce full simulation results are emphasized. (author)
Fermion-fermion and boson-boson amplitudes: surprising similarities
Dvoeglazov, Valeri V
2007-01-01
Amplitudes for fermion-fermion, boson-boson and fermion-boson interactions are calculated in the second order of perturbation theory in the Lobachevsky space. An essential ingredient of the model is the Weinberg's 2(2j+1)-component formalism for describing a particle of spin j. The boson-boson amplitude is then compared with the two-fermion amplitude obtained long ago by Skachkov on the basis of the Hamiltonian formulation of quantum field theory on the mass hyperboloid, p_0^2 - p^2=M^2, proposed by Kadyshevsky. The parametrization of the amplitudes by means of the momentum transfer in the Lobachevsky space leads to same spin structures in the expressions of T-matrices for the fermion case and the boson case. However, certain differences are found. Possible physical applications are discussed.
On the origins and the historical roots of the Higgs boson research from a bibliometric perspective
Barth, Andreas; Bornmann, Lutz; Mutz, Ruediger
2014-01-01
Subject of our present paper is the analysis of the origins or historical roots of the Higgs boson research from a bibliometric perspective, using a segmented regression analysis in a reference publication year spectroscopy (RPYS). Our analysis is based on the references cited in the Higgs boson publications published since 1974. The objective of our analysis consists of identifying concrete individual publications in the Higgs boson research context to which the scientific community frequently had referred to. As a consequence, we are interested in seminal works which contributed to a high extent to the discovery of the Higgs boson. Our results show that researchers in the Higgs boson field preferably refer to more recently published papers - particular papers published since the beginning of the sixties. For example, our analysis reveals seven major contributions which appeared within the sixties: Englert and Brout (1964), Higgs (1964, 2 papers), and Guralnik et al. (1964) on the Higgs mechanism as well as ...
Searching for the Higgs Boson in Pairs of Tau Leptons in Data from the ATLAS Experiment
Rosendahl, Peter Lundgaard
2013-01-01
One of the key questions in particle physics today, is the origin of the electroweak symmetry breaking. The answer to this question will most likely be solved with the data provided by the Large Hadron Collider which started colliding protons in 2008. Many ideas have been posed to how particles gain their masses. The most promising of these ideas is the Higgs mechanism which predicts the existence of a new massive scalar boson, the Higgs boson. Since the discovery of a new part...
Spring, Justin B; Humphreys, Peter C; Kolthammer, W Steven; Jin, Xian-Min; Barbieri, Marco; Datta, Animesh; Thomas-Peter, Nicholas; Langford, Nathan K; Kundys, Dmytro; Gates, James C; Smith, Brian J; Smith, Peter G R; Walmsley, Ian A
2013-01-01
While universal quantum computers ideally solve problems such as factoring integers exponentially more efficiently than classical machines, the formidable challenges in building such devices motivate the demonstration of simpler, problem-specific algorithms that still promise a quantum speedup. We construct a quantum boson sampling machine (QBSM) to sample the output distribution resulting from the nonclassical interference of photons in an integrated photonic circuit, a problem thought to be exponentially hard to solve classically. Unlike universal quantum computation, boson sampling merely requires indistinguishable photons, linear state evolution, and detectors. We benchmark our QBSM with three and four photons and analyze sources of sampling inaccuracy. Our studies pave the way to larger devices that could offer the first definitive quantum-enhanced computation.
Prospects for measurements of the Higgs boson couplings at TLEP
Bachtis, M
2014-01-01
The discovery by the ATLAS and CMS experiments of a new boson with mass around 125 GeV and with measured properties compatible with those of a Standard-Model Higgs boson, coupled with the absence of discoveries of phenomena beyond the Standard Model up to scales of sev- eral hundred GeV, has triggered interest in ideas for future Higgs factories. A new circular e + e collider hosted in a 80 to 100 km tunnel, TLEP, is among the most attractive solutions proposed so far. It has a clean experimental environment, produces high luminosity for Higgs boson stud- ies, accommodates multiple detectors, and can reach energies up to the t ̄ t threshold and beyond. Moreover, being the natural precursor of the VHE-LHC, a 100 TeV hadron machine in the same tunnel, it builds up a long-term vision for particle physics. This paper describes the expected precision on the measurement of the Higgs boson couplings with a TLEP run between 250 and 350 GeV.
Effects of Family Nonuniversal Z' Boson on Leptonic Decays of Higgs and Weak Bosons
Chiang, Cheng-Wei; Nomura, Takaaki; Tandean, Jusak
2013-01-01
Though not completely a surprise according to the standard model and existing indirect constraints, the Higgs-like particle, h, of mass around 125 GeV recently observed at the LHC may offer an additional window to physics beyond the standard model. In particular, its decay pattern can be modified by the existence of new particles. One of the popular scenarios involves a Z' boson associated with an extra Abelian gauge group. In this study, we explore the potential effects of such a boson with ...
Interacting boson approximation
International Nuclear Information System (INIS)
Lectures notes on the Interacting Boson Approximation are given. Topics include: angular momentum tensors; properties of T/sub i//sup (n)/ matrices; T/sub i//sup (n)/ matrices as Clebsch-Gordan coefficients; construction of higher rank tensors; normalization: trace of products of two s-rank tensors; completeness relation; algebra of U(N); eigenvalue of the quadratic Casimir operator for U(3); general result for U(N); angular momentum content of U(3) representation; p-Boson model; Hamiltonian; quadrupole transitions; S,P Boson model; expectation value of dipole operator; S-D model: U(6); quadratic Casimir operator; an O(5) subgroup; an O(6) subgroup; properties of O(5) representations; quadratic Casimir operator; quadratic Casimir operator for U(6); decomposition via SU(5) chain; a special O(3) decomposition of SU(3); useful identities; a useful property of D/sub αβγ/(α,β,γ = 4-8) as coupling coefficients; explicit construction of T/sub x//sup (2)/ and d/sub αβγ/; D-coefficients; eigenstates of T3; and summary of T = 2 states
International Nuclear Information System (INIS)
A study of the expected sensitivity of the ATLAS experiment to discover the Standard Model Higgs boson produced via vector boson fusion (VBF) and its decay to H→ ττ→ ll+4ν is presented. The study is based on simulated proton-proton collisions at a centre-of-mass energy of 14 TeV. For the first time the discovery potential is evaluated in the presence of additional proton-proton interactions (pile-up) to the process of interest in a complete and consistent way. Special emphasis is placed on the development of background estimation techniques to extract the main background processes Z→ττ and t anti t production using data. The t anti t background is estimated using a control sample selected with the VBF analysis cuts and the inverted b-jet veto. The dominant background process Z→ττ is estimated using Z→μμ events. Replacing the muons of the Z→μμ event with simulated τ-leptons, Z→ττ events are modelled to high precision. For the replacement of the Z boson decay products a dedicated method based on tracks and calorimeter cells is developed. Without pile-up a discovery potential of 3σ to 3.4σ in the mass range 115 GeVH-1. In the presence of pile-up the signal sensitivity decreases to 1.7σ to 1.9σ mainly caused by the worse resolution of the reconstructed missing transverse energy.
Energy Technology Data Exchange (ETDEWEB)
Schmitz, Martin
2011-05-17
A study of the expected sensitivity of the ATLAS experiment to discover the Standard Model Higgs boson produced via vector boson fusion (VBF) and its decay to H{yields} {tau}{tau}{yields} ll+4{nu} is presented. The study is based on simulated proton-proton collisions at a centre-of-mass energy of 14 TeV. For the first time the discovery potential is evaluated in the presence of additional proton-proton interactions (pile-up) to the process of interest in a complete and consistent way. Special emphasis is placed on the development of background estimation techniques to extract the main background processes Z{yields}{tau}{tau} and t anti t production using data. The t anti t background is estimated using a control sample selected with the VBF analysis cuts and the inverted b-jet veto. The dominant background process Z{yields}{tau}{tau} is estimated using Z{yields}{mu}{mu} events. Replacing the muons of the Z{yields}{mu}{mu} event with simulated {tau}-leptons, Z{yields}{tau}{tau} events are modelled to high precision. For the replacement of the Z boson decay products a dedicated method based on tracks and calorimeter cells is developed. Without pile-up a discovery potential of 3{sigma} to 3.4{sigma} in the mass range 115 GeV
Boson stars with nonminimal coupling
Marunovic, Anja
2015-01-01
Boson stars coupled to Einstein's general relativity possess some features similar to gravastars, such as the anisotropy in principal pressures and relatively large compactness ($\\mu_{max} = 0.32$). However, no matter how large the self-interaction is, the ordinary boson star cannot obtain arbitrarily large compression and as such does not represent a good black hole mimicker. When the boson star is nonminimally coupled to gravity, the resulting configurations resemble more the dark energy stars then the ordinary boson stars, with compactness significantly larger then that in ordinary boson stars (if matter is not constrained with the energy conditions). The gravitationally bound system of a boson star and a global monopole represents a good black hole mimicker.
The Constrained NMSSM with a 126 GeV Higgs boson: A global analysis
Kowalska, Kamila; Munir, Shoaib; Roszkowski, Leszek; Sessolo, Enrico Maria; Trojanowski, Sebastian; Tsai, Yue-Lin Sming
2012-01-01
We present the first global analysis of the Constrained NMSSM that investigates the impact of the recent discovery of a 126 GeV Higgs-like boson, of the observation of a signal for BR(B_s->\\mu^+\\mu^-), and of constraints on supersymmetry from ~5/fb of data accumulated at the LHC, as well as of other relevant constraints from colliders, flavor physics and dark matter. We consider three possible cases, assuming in turn that the discovered Higgs boson is: i) the lightest Higgs boson of the model...
The second Kaluza-Klein neutral Higgs bosons in the minimal Universal Extra Dimension model
Chang, Sanghyeon; Lee, Kang Young; Song, Jeonghyeon
2011-01-01
Loop-induced decay of a neutral Higgs boson into a pair of gluons or photons has great implications for the Higgs discovery at the LHC. If the Higgs boson is heavy with mass above $\\sim 500\\gev$, however, these radiative branching ratios are very suppressed in the standard model (SM), as the new decay channels are kinematically open. We note that these radiative decays can be sizable for the heavy CP-odd second Kaluza-Klein (KK) mode of the Higgs boson, $\\chi^\\tw$, in the minimal universal ex...
Higgs boson production with one bottom quark including higher-order soft-gluon corrections
Field, B.; Jackson, C.B.(Department of Physics, University of Texas at Arlington, Arlington, TX 76019, USA); Reina, L.
2007-01-01
A Higgs boson produced in association with one or more bottom quarks is of great theoretical and experimental interest to the high-energy community. A precise prediction of its total and differential cross-section can have a great impact on the discovery of a Higgs boson with large bottom-quark Yukawa coupling, like the scalar (h^0 and H^0) and pseudoscalar (A^0) Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) in the region of large \\tan\\beta. In this paper we apply the thres...
The Curious Ontology of a Light Higgs Boson
Riordan, Michael
2016-03-01
When the Superconducting Super Collider was being contemplated and designed in the mid-1980s, few high-energy physicists considered it likely that a light Higgs boson, as was eventually discovered at the Large Hadron Collider, would exist. Most theorists expected that the Higgs boson would occur at a mass near the TeV scale, and accelerator physicists designed the Super Collider accordingly. The possibility of a light Higgs boson with a mass less than 200 GeV began to be taken seriously during the 1990s, especially after the 1995 Fermilab discovery of the top quark near 175 GeV, but it was too late to influence the SSC design. With a peak collision energy of 40 TeV, this collider was guaranteed to discover the Higgs boson -- or whatever other mass-generating phenomenon might be occurring in the Standard Model -- even if it were to appear at masses or energies up to 2 TeV. As it turned out, therefore, the SSC was overdesigned for its principal physics goal. A substantially smaller Fermilab project known as the Dedicated Collider, which never made it beyond the drawing boards, could probably have allowed the 125 GeV Higgs boson to be discovered at least a decade earlier than it occurred at the LHC.
LHC Signals for Warped Electroweak Charged Gauge Bosons
Agashe, Kaustubh; Han, Tao; Huang, Gui-Yu; Soni, Amarjit
2008-01-01
We study signals at the Large Hadron Collider (LHC) for the Kaluza-Klein (KK) excitations of electroweak charged gauge bosons in the framework of the Standard Model (SM) fields propagating in the bulk of a warped extra dimension. Such a scenario can solve both the Planck-weak and flavor hierarchy problems of the SM. There are two such charged states in this scenario with couplings to light quarks and leptons being suppressed relative to those in the SM, whereas the couplings to top/bottom quarks are enhanced, similar to the case of electroweak neutral gauge bosons previously studied. However, unlike the case of electroweak neutral gauge bosons, there is no irreducible QCD background (including pollution from possibly degenerate KK gluons) for decays to top + bottom final state so that this channel is useful for the discovery of the charged states. Moreover, decays of electroweak charged gauge bosons to longitudinal W, Z and Higgs are enhanced just as for the neutral bosons. However, unlike for the neutral gau...
Study of Higgs Boson Pair Production at Linear Collider
Desch, Klaus; Kühl, T; Raspereza, A V
2004-01-01
We study the potential of the TESLA linear collider operated at a center-of-mass energy of 500 to 1000 GeV for the measurement of the neutral Higgs boson properties within the framework of the MSSM. The process of associated Higgs boson production with subsequent decays of Higgs bosons into b-quark and tau-lepton pairs is considered. An integrated luminosity of 500 fb^{-1} is assumed at each energy. The Higgs boson masses and production cross sections are measured by reconstructing the bbbb and bb\\tau\\tau final states. The precision of these measurements is evaluated in dependence of the Higgs boson masses. Under the assumed experimental conditions a statistical accuracy ranging from 0.1 to 1.0 GeV is achievable on the Higgs boson mass. The topological cross section \\sigma(e+e- -> HA -> bbbb) can be determined with the relative precision of 1.5 - 6.6 % and cross sections \\sigma(e+e- -> HA -> bb \\tau\\tau) and \\sigma(e+e- -> HA -> \\tau\\tau bb) with precision of 4 - 30 %. Constraints on the Higgs boson widths ca...
Compact (A)dS Boson Stars and Shells
Hartmann, Betti; Kunz, Jutta; Schaffer, Isabell
2013-01-01
We present compact Q-balls in an (Anti-)de Sitter background in D dimensions, obtained with a V-shaped potential of the scalar field. Beyond critical values of the cosmological constant compact Q-shells arise. By including the gravitational back-reaction, we obtain boson stars and boson shells with (Anti-)de Sitter asymptotics. We analyze the physical properties of these solutions and determine their domain of existence. In four dimensions we address some astrophysical aspects.
Big bang machine searching for the Higgs boson particle
2015-01-01
On July 4, 2012, scientists at the giant atom smashing facility at CERN announced the discovery of a subatomic particle that seems like a tantalizingly close match to the elusive Higgs Boson, thought to be responsible for giving all the stuff in the universe its mass. Since it was first proposed nearly fifty years ago, the Higgs has been the holy grail of particle physicists: in finding it they validate the “standard model” that underlies all of modern physics and open the door to new discoveries when CERN’s giant collider switches on at higher power in 2015.
Boson star at finite temperature
Latifah, S; Mart, T
2014-01-01
By using a simple thermodynamical method we confirm the finding of Chavanis and Harko that stable Bose-Einstein condensate stars can form. However, by using a thermodynamically consistent boson equation of state, we obtain a less massive Bose-Einstein condensate star compared to the one predicted by Chavanis and Harko. We also obtain that the maximum mass of a boson star is insensitive to the change of matter temperature. However, the mass of boson star with relatively large radius depends significantly on the temperature of the boson matter.
Bosonization and Lie Group Structure
Ha, Yuan K
2015-01-01
We introduce a concise quantum operator formula for bosonization in which the Lie group structure appears in a natural way. The connection between fermions and bosons is found to be exactly the connection between Lie group elements and the group parameters. Bosonization is an extraordinary way of expressing the equation of motion of a complex fermion field in terms of a real scalar boson in two dimensions. All the properties of the fermion field theory are known to be preserved under this remarkable transformation with substantial simplification and elucidation of the original theory, much like Lie groups can be studied by their Lie algebras.
Production of electroweak bosons at colliders
Indian Academy of Sciences (India)
Matthias U Mozer
2012-10-01
The collider experiments at the Tevatron and LHC are accumulating samples of electroweak bosons of unprecedented size. These huge samples can be used to observe rare processes, such as diboson production which have the potential to show enhancements due to new physics. Alternatively, the great statistical power of the samples allows for detailed studies of electroweak production mechanisms and correspondingly QCD and the proton structure.
mu_x boosted-bottom-jet tagging and Z-prime boson searches
Pedersen, Keith
2015-01-01
We present a new technique for tagging heavy-flavor jets with p_T > 500 GeV called "mu_x tagging." Current track-based methods of b-jet tagging lose efficiency and experience a large rise in fake rate in the boosted regime. Using muons from B hadron decay, we combine angular information and jet substructure to tag b jets, c jets, light jets, and "light-heavy" jets (those containing B hadrons from gluon splitting). We find tagging efficiencies of epsilon_b = 14%, epsilon_c = 6.5%, epsilon_{light-light} = 0.14%, and epsilon_{light-heavy} = 0.5%, respectively, that are nearly independent of transverse momentum at high energy. We demonstrate the usefulness of this new scheme by examining the discovery potential for multi-TeV leptophobic Z-prime bosons in the boosted-b-tagged dijet channel at the Large Hadron Collider.
μx boosted-bottom-jet tagging and Z' boson searches
Pedersen, Keith; Sullivan, Zack
2016-01-01
We present a new technique for tagging heavy-flavor jets with pT>500 GeV called "μx tagging." Current track-based methods of b -jet tagging lose efficiency and experience a large rise in fake rate in the boosted regime. Using muons from B hadron decay, we combine angular information and jet substructure to tag b jets, c jets, light jets, and "light-heavy" jets (those containing B hadrons from gluon splitting). We find tagging efficiencies of ɛb=14 %, ɛc=6.5 %, ɛlight-light=0.14 % , and ɛlight-heavy=0.5 %, respectively, that are nearly independent of transverse momentum at high energy. We demonstrate the usefulness of this new scheme by examining the discovery potential for multi-TeV leptophobic Z' bosons in the boosted-b -tagged dijet channel at the Large Hadron Collider.
Chips for discovering the Higgs boson and other particles at CERN: Present and future
Snoeys, W
2015-01-01
Integrated circuits and devices revolutionized particle physics experiments, and have been essential in the recent discovery of the Higgs boson by the ATLAS and CMS experiments at the Large Hadron Collider at CERN [1,2]. Particles are accelerated and brought into collision at specific interaction points where detectors, giant cameras of about 40 m long by 20 m in diameter, take pictures of the collision products as they fly away from the collision point. These detectors contain millions of channels, often implemented as reverse biased silicon pin diode arrays covering areas of up to 200 m2 in the center of the experiment, generating a small (~1fC) electric charge upon particle traversals. Integrated circuits provide the readout, and accept collision rates of about 40 MHz with on-line selection of potentially interesting events before data storage. Important limitations are power consumption, radiation tolerance, data rates, and system issues like robustness, redundancy, channel-to-channel uniformity, timing d...
Van Oosten, L.N.; M. Pieterse; Pinkse, M.W.H.; Verhaert, P.D.E.M.
2015-01-01
Animal venoms and toxins are a valuable source of bioactive peptides with pharmacologic relevance as potential drug leads. A large subset of biologically active peptides discovered up till now contain disulfide bridges that enhance stability and activity. To discover new members of this class of peptides, we developed a workflow screening specifically for those peptides that contain inter- and intra-molecular disulfide bonds by means of three-dimensional (3D) mass mapping. Two intrinsic prope...
The ATLAS collaboration
2016-01-01
The High Luminosity Large Hadron Collider is expected to be completed and operational in the second half of 2026, and will necessitate substantial upgrades to the ATLAS inner tracker detector. The impact of increased tracking coverage in the forward direction was investigated in terms of the separation of vector-boson fusion and gluon fusion-mediated Higgs-boson decays to four leptons in association with two jets. For an analysis dominated by statistical uncertainty, with vector-boson fusion production events treated as signal on top of gluon fusion background, the extension of tracking from pseudorapidity $|\\eta| < 2.7$ to $|\\eta| < 4.0$ improved the prospective vector-boson fusion discovery significance by 16%, while the relative uncertainty on the signal strength $\\Delta\\mu/\\mu$ was reduced by 6%.
International Nuclear Information System (INIS)
We study the dynamic structure factor of a one-dimensional Bose gas confined in an optical lattice and modeled by the Bose–Hubbard Hamiltonian, using a variety of numerical and analytical approaches. The dynamic structure factor, experimentally measurable by Bragg spectroscopy, is studied in three relevant cases: in the clean regime, featuring either a superfluid or a Mott phase; and in the presence of two types of (quasi-)disordered external potentials: a quasi-periodic potential obtained from a bichromatic superlattice and a random box disorder—both featuring a Bose-glass phase. In the clean case, we show the emergence of a gapped doublon mode (corresponding to a repulsively bound state) for incommensurate filling, well separated from the low-energy acoustic mode. In the disordered case, we show that the dynamic structure factor provides direct insight into the spatial structure of the excitations, unveiling their localized nature, which represents a fundamental signature of the Bose-glass phase. Furthermore, it provides a clear fingerprint of the very nature of the localization mechanism which differs for the two kinds of disorder potentials we consider. In special cases, the dynamic structure factor may provide an estimate of the position of the localization transition from superfluid to Bose glass, in a complementary manner to the information deduced from the momentum distribution. (paper)
Mott-superfluid transition of q-deformed bosons
International Nuclear Information System (INIS)
The effect of q-deformation of the bosonic algebra on the Mott-superfluid transition for interacting lattice bosons described by the Bose–Hubbard model is studied using mean-filed theory. It has been shown that the Mott state proliferates and the initial periodicity of the Mott lobes as a function of the chemical potential disappears as the q-deformation increases. The ground state phase diagram as a function of the q-parameter exhibits superfluid order, which intervenes in narrow regions between Mott lobes, demonstrating the new concept of statistically induced quantum phase transition. - Highlights: • We study the effect of q-deformed bosons on superfluid transition. • A mean-field theory is employed. • Bosons can change statistics due to deformation of the commutation rules. • Statistically induced quantum phase transition is found
Mott-superfluid transition of q-deformed bosons
Energy Technology Data Exchange (ETDEWEB)
Kopeć, T.K., E-mail: kopec@int.pan.wroc.pl
2015-10-16
The effect of q-deformation of the bosonic algebra on the Mott-superfluid transition for interacting lattice bosons described by the Bose–Hubbard model is studied using mean-filed theory. It has been shown that the Mott state proliferates and the initial periodicity of the Mott lobes as a function of the chemical potential disappears as the q-deformation increases. The ground state phase diagram as a function of the q-parameter exhibits superfluid order, which intervenes in narrow regions between Mott lobes, demonstrating the new concept of statistically induced quantum phase transition. - Highlights: • We study the effect of q-deformed bosons on superfluid transition. • A mean-field theory is employed. • Bosons can change statistics due to deformation of the commutation rules. • Statistically induced quantum phase transition is found.
Directory of Open Access Journals (Sweden)
Steven M Valles
Full Text Available BACKGROUND: Nylanderia pubens (Forel is an invasive ant species that in recent years has developed into a serious nuisance problem in the Caribbean and United States. A rapidly expanding range, explosive localized population growth, and control difficulties have elevated this ant to pest status. Professional entomologists and the pest control industry in the United States are urgently trying to understand its biology and develop effective control methods. Currently, no known biological-based control agents are available for use in controlling N. pubens. METHODOLOGY AND PRINCIPAL FINDINGS: Metagenomics and pyrosequencing techniques were employed to examine the transcriptome of field-collected N. pubens colonies in an effort to identify virus infections with potential to serve as control agents against this pest ant. Pyrosequencing (454-platform of a non-normalized N. pubens expression library generated 1,306,177 raw sequence reads comprising 450 Mbp. Assembly resulted in generation of 59,017 non-redundant sequences, including 27,348 contigs and 31,669 singlets. BLAST analysis of these non-redundant sequences identified 51 of potential viral origin. Additional analyses winnowed this list of potential viruses to three that appear to replicate in N. pubens. CONCLUSIONS: Pyrosequencing the transcriptome of field-collected samples of N. pubens has identified at least three sequences that are likely of viral origin and, in which, N. pubens serves as host. In addition, the N. pubens transcriptome provides a genetic resource for the scientific community which is especially important at this early stage of developing a knowledgebase for this new pest.
Lykken, Joseph D.
1996-01-01
A broad class of supersymmetric extensions of the standard model predict a Z' vector boson whose mass is naturally in the range 250 GeV < M_Z' < 2 TeV. To avoid unacceptably large mixing with the Z, one requires either a discrete tuning of the U(1)' charges or a leptophobic Z'. Both cases are likely to arise as the low energy limits of heterotic string compactifications, but a survey of existing realistic string models provides no acceptable examples. A broken U(1)' leads to additional D-term...
DEFF Research Database (Denmark)
Sannino, Francesco
2013-01-01
via first principle lattice simulations with encouraging results. The new findings show that the recent naive claims made about new strong dynamics at the electroweak scale being disfavoured by the discovery of a not-so-heavy composite Higgs are unwarranted. I will then introduce the more speculative......I discuss the impact of the discovery of a Higgs-like state on composite dynamics starting by critically examining the reasons in favour of either an elementary or composite nature of this state. Accepting the standard model interpretation I re-address the standard model vacuum stability within a...... has been challenged by the discovery of a not-so-heavy Higgs-like state. I will therefore review the recent discovery \\cite{Foadi:2012bb} that the standard model top-induced radiative corrections naturally reduce the intrinsic non-perturbative mass of the composite Higgs state towards the desired...
DEFF Research Database (Denmark)
Dias, Gustavo Fruet; Scherrer, Cristina; Papailias, Fotis
There is a large literature that investigates how homogenous securities traded on different markets incorporate new information (price discovery analysis). We extend this concept to the stochastic volatility process and investigate how markets contribute to the efficient stochastic volatility whi...
Deformation quantization of bosonic strings
International Nuclear Information System (INIS)
Deformation quantization of bosonic strings is considered. We show that the light-cone gauge is the most convenient classical description to perform the quantization of bosonic strings in the deformation quantization formalism. Similar to the field theory case, the oscillator variables greatly facilitates the analysis. The mass spectrum, propagators and the Virasoro algebra are finally described within this deformation quantization scheme. (author)
Top partner discovery in the T→tZ channel at the LHC
International Nuclear Information System (INIS)
In this paper we study the discovery potential of the LHC run II for heavy vector-like top quarks in the decay channel to a top and a Z boson. Despite the usually smaller branching ratio compared to charged-current decays this channel is rather clean and allows a complete mass reconstruction of the heavy top. The latter is achieved in the fully hadronic top channel using boosted jet and jet substructure techniques. To be as model-independent as possible, a simplified model approach with only two free parameters has been applied. The results are presented in terms of parameter space regions for 3σ evidence or 5σ discovery for such new states in that channel.
A Minimally Symmetric Higgs Boson
Low, Ian
2014-01-01
Models addressing the naturalness of a light Higgs boson typically employ symmetries, either bosonic or fermionic, to stabilize the Higgs mass. We consider a setup with the minimal amount of symmetries: four shift symmetries acting on the four components of the Higgs doublet, subject to the constraints of linearly realized SU(2)xU(1) electroweak symmetry. Up to terms that explicitly violate the shift symmetries, the effective lagrangian can be derived, irrespective of the spontaneously broken group G in the ultraviolet, and is universal in all models where the Higgs arises as a pseudo-Nambu-Goldstone boson (PNGB). Very high energy scatterings of vector bosons could provide smoking gun signals of a minimally symmetric Higgs boson.
Bardhan, Jaydeep P
2012-01-01
We present two open-source (BSD) implementations of ellipsoidal harmonic expansions for solving problems of potential theory using separation of variables. Ellipsoidal harmonics are used surprisingly infrequently, considering their substantial value for problems ranging in scale from molecules to the entire solar system. In this article, we suggest two possible reasons for the paucity relative to spherical harmonics. The first is essentially historical---ellipsoidal harmonics developed during the late 19th century and early 20th, when it was found that only the lowest-order harmonics are expressible in closed form. Each higher-order term requires the solution of an eigenvalue problem, and tedious manual computation seems to have discouraged applications and theoretical studies. The second explanation is practical: even with modern computers and accurate eigenvalue algorithms, expansions in ellipsoidal harmonics are significantly more challenging to compute than those in Cartesian or spherical coordinates. The...
Malami, Ibrahim; Abdul, Ahmad Bustamam; Abdullah, Rasedee; Bt Kassim, Nur Kartinee; Waziri, Peter; Christopher Etti, Imaobong
2016-01-01
Uridine-cytidine kinase 2 is implicated in uncontrolled proliferation of abnormal cells and it is a hallmark of cancer, therefore, there is need for effective inhibitors of this key enzyme. In this study, we employed the used of in silico studies to find effective UCK2 inhibitors of natural origin using bioinformatics tools. An in vitro kinase assay was established by measuring the amount of ADP production in the presence of ATP and 5-fluorouridine as a substrate. Molecular docking studies revealed an interesting ligand interaction with the UCK2 protein for both flavokawain B and alpinetin. Both compounds were found to reduce ADP production, possibly by inhibiting UCK2 activity in vitro. In conclusion, we have identified flavokawain B and alpinetin as potential natural UCK2 inhibitors as determined by their interactions with UCK2 protein using in silico molecular docking studies. This can provide information to identify lead candidates for further drug design and development. PMID:27070566
Degenerate states in the scalar boson spectrum. Is the Higgs Boson a Twin ?
Stech, Berthold
2013-01-01
The extension of the standard model to $SU(3)_L\\times SU(3)_R \\times SU(3)_C$ is considered. Spontaneous symmetry breaking requires two $(3^*, 3, 1)$ Higgs field multiplets with a strong hierarchical structure of their vacuum expectation values. An invariant potential is constructed to provide for these vacuum expectation values. This potential gives masses to all scalar fields apart from the 15 Goldstone bosons. In case there exists a one-to-one correspondence between the vacuum expectation ...
Higgs Boson and the Large Hadron Collider
International Nuclear Information System (INIS)
The Standard Model of particle physics has been extremely successful in explaining all the precision data collected during the past few decades. The model, however, was incomplete with one of the key particles still not experimentally observed till 2012. This particle is predicted by the theory in the context of providing mass to the fundamental constituents as well as the exchange particles W and Z bosons. In the recent past, two experiments, ATLAS and CMS operating at the Large Hadron Collider, CERN have observed the evidence of a new state. Search signal of this object has been motivated by the Higgs boson within the Standard Model. These results have been consolidated with newer data and some attempt has gone to determine some of the properties of this newly observed state. Some of the most important recent results in this context are presented in this lecture. Several groups from India have participated in the LHC program and contributed to various aspects like the machine, computing grid and the experiments. In particular, 3 institutes and 2 University groups have been a member of the CMS collaboration and took part in the discovery of the new state. The participation of the Indian groups are also highlighted. (author)
Multi-Higgs systems in bosonic technicolor
International Nuclear Information System (INIS)
Multi-Higgs systems are combined with bosonic technicolor to construct a viable model of TeV physics. In such models, there is potentially a flavor problem in either the supersymmetric or the Higgs sector. However, the naturally larger mass scales for supersymmetry breaking and Higgs masses, which is a salient feature of bosonic technicolor, allows one to resolve the GUT-hierarchy problem without large flavor violation. With a judicious choice of the Higgs system, hierarchies of family masses and mixing angles of the right order of magnitude are achieved without resorting to small Yukawa couplings. Some of these masses and mixing angles are generated by radiative corrections. At energies below 100 GeV the standard model is reproduced, whereas at TeV energies a rich phenomenology of supersymmetric states and techni-hadrons is predicted. This paper presents precise formulas to describe many aspects of the model and its phenomenology at tree and one-loop levels
Directory of Open Access Journals (Sweden)
Marine E. Bozdaganyan
2014-01-01
Full Text Available Molecular docking is a common method for searching new potential drugs. Improvement of the results of docking can be achieved by different ways-one of them is molecular dynamics simulations of protein-ligand complexes. As a model for our research we chose M2 membrane protein from influenza virus. M2 protein is a high selective tetrameric pH-gated proton channel. It was previously shown that Omeprazole Family Compounds (OFC block the "proton pump", though we hypothesized further that they could interfere with the mechanism of fusion of the virus envelope and endosomal membrane, thereby hindering the M2 proton pump mechanism of influenza viruses. We carried out a Molecular Dynamics (MD simulation in order to predict constant of binding for OFC. We simulated M2 Protein (PDB code 3C9J in complex with its ligands: Amantadine, rimantadine as positive controls and omeprazole as putative ligand. We made use of molecular docking as well as the thermodynamic integration method to estimate binding free energies of the ligands. We demonstrate that the thermodynamic integration method predicts free energies of ligand binding better than molecular docking while embedding of M2 protein in a membrane further improves the calculated free energy values. Free energy calculations imply omeprazole as a potent anti-viral drug.
Discovery of potential drugs for human-infecting H7N9 virus containing R294K mutation
Directory of Open Access Journals (Sweden)
He JY
2014-12-01
Full Text Available Jiao-Yu He,1,* Cheng Li,2,* Guo Wu3 1College of Life Sciences and Key Laboratory for Bio-resources of Ministry of Education, Sichuan University, 2College of Agronomy, Sichuan Agricultural University, 3College of Life Sciences, Sichuan Normal University, Chengdu, People’s Republic of China *These authors contributed equally to this work Background: After the first epidemic wave from February through May 2013, the influenza A (H7N9 virus emerged and has followed a second epidemic wave since June 2013. As of June 27, 2014, the outbreak of H7N9 had caused 450 confirmed cases of human infection, with 165 deaths included. The case-fatality rate of all confirmed cases is about 36%, making the H7N9 virus a significant threat to people’s health. At present, neuraminidase inhibitors are the only licensed antiviral medications available to treat H7N9 infections in humans. Oseltamivir is the most commonly used inhibitor, and it is also a front-line drug for the threatening H7N9. Unfortunately, it has been reported that patients treated with oseltamivir can induce R294K (Arg294Lys substitution in the H7N9 virus, which is a rare mutation and can reduce the antiviral efficacy of inhibitors. Even worse, deaths caused by such mutation after oseltamivir treatment have already been reported, indicating that the need to find substitutive neuraminidase inhibitors for currently available drugs to treat drug-resistant H7N9 is really pressing.Materials and methods: First, the structure of H7N9 containing the R294K substitution was downloaded from the Protein Data Bank, and structural information of approved drugs was downloaded from the ZINC (ZINC Is Not Commercial database. Taking oseltamivir carboxylate as a reference drug, we then filtered these molecules through virtual screening to find out potential inhibitors targeting the mutated H7N9 virus. For further evaluation, we carried out a 14 ns molecular dynamic simulation for each H7N9–drug complex and
Energy Technology Data Exchange (ETDEWEB)
Girard, L
2004-12-15
Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release {gamma}-ray studies, in the energy range from GeV to TeV, using the tracker system, for {gamma}-rays converted in e{sup +}e{sup -} pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for {gamma}-astrophysics is presented. While exposure maps of the {gamma}--sky are computed for one year of data taking with the {gamma}--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the Galactic Center. (author)
van Oosten, Luuk N.; Pieterse, Mervin; Pinkse, Martijn W. H.; Verhaert, Peter D. E. M.
2015-12-01
Animal venoms and toxins are a valuable source of bioactive peptides with pharmacologic relevance as potential drug leads. A large subset of biologically active peptides discovered up till now contain disulfide bridges that enhance stability and activity. To discover new members of this class of peptides, we developed a workflow screening specifically for those peptides that contain inter- and intra-molecular disulfide bonds by means of three-dimensional (3D) mass mapping. Two intrinsic properties of the sulfur atom, (1) its relatively large negative mass defect, and (2) its isotopic composition, allow for differentiation between cysteine-containing peptides and peptides lacking sulfur. High sulfur content in a peptide decreases the normalized nominal mass defect (NMD) and increases the normalized isotopic shift (NIS). Hence in a 3D plot of mass, NIS, and NMD, peptides with sulfur appear in this plot with a distinct spatial localization compared with peptides that lack sulfur. In this study we investigated the skin secretion of two frog species; Odorrana schmackeri and Bombina variegata. Peptides from the crude skin secretions were separated by nanoflow LC, and of all eluting peptides high resolution zoom scans were acquired in order to accurately determine both monoisotopic mass and average mass. Both the NMD and the NIS were calculated from the experimental data using an in-house developed MATLAB script. Candidate peptides exhibiting a low NMD and high NIS values were selected for targeted de novo sequencing, and this resulted in the identification of several novel inter- and intra-molecular disulfide bond containing peptides.
The Discovery of the Top Quark
Sinervo, P.K.
1995-12-01
The top quark and the Higgs boson are the heaviest elementary particles predicted by the standard model. The four lightest quark flavours, the up, down, strange and charm quarks, were well-established by the mid-1970's. The discovery in 1977 of the {Tau} resonances, a new family of massive hadrons, required the introduction of the fifth quark flavour. Experimental and theoretical studies have indicated that this quark also has a heavier partner, the top quark.
Energy Technology Data Exchange (ETDEWEB)
Kanemura, Shinya, E-mail: kanemu@sci.u-toyama.ac.jp [Department of Physics, University of Toyama, Toyama 930-8555 (Japan); Yokoya, Hiroshi, E-mail: hyokoya@sci.u-toyama.ac.jp [Department of Physics, University of Toyama, Toyama 930-8555 (Japan); Zheng, Ya-Juan, E-mail: yjzheng218@gmail.com [CTS, CASTS and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China)
2014-09-15
We discuss complementarity of discovery reaches of heavier neutral Higgs bosons and charged Higgs bosons at the LHC and the International Linear Collider (ILC) in two Higgs doublet models (2HDMs). We perform a comprehensive analysis on their production and decay processes for all types of Yukawa interaction under the softly-broken discrete symmetry which is introduced to avoid flavour changing neutral currents, and we investigate parameter spaces of discovering additional Higgs bosons at the ILC beyond the LHC reach. We find that the 500 GeV run of the ILC with the integrated luminosity of 500 fb{sup −1} shows an advantage for discovering the additional Higgs bosons in the region where the LHC cannot discover them with the integrated luminosity of 300 fb{sup −1}. For the 1 TeV run of the ILC with the integrated luminosity of 1 ab{sup −1}, production processes of an additional Higgs boson associated with the top quark can be useful as discovery channels in some parameter spaces where the LHC with the integrated luminosity of 3000 fb{sup −1} cannot reach. It is emphasized that the complementary study at the LHC and the ILC is useful not only to survey additional Higgs bosons at the TeV scale, but also to discriminate types of Yukawa interaction in the 2HDM.
International Nuclear Information System (INIS)
We discuss complementarity of discovery reaches of heavier neutral Higgs bosons and charged Higgs bosons at the LHC and the International Linear Collider (ILC) in two Higgs doublet models (2HDMs). We perform a comprehensive analysis on their production and decay processes for all types of Yukawa interaction under the softly-broken discrete symmetry which is introduced to avoid flavour changing neutral currents, and we investigate parameter spaces of discovering additional Higgs bosons at the ILC beyond the LHC reach. We find that the 500 GeV run of the ILC with the integrated luminosity of 500 fb−1 shows an advantage for discovering the additional Higgs bosons in the region where the LHC cannot discover them with the integrated luminosity of 300 fb−1. For the 1 TeV run of the ILC with the integrated luminosity of 1 ab−1, production processes of an additional Higgs boson associated with the top quark can be useful as discovery channels in some parameter spaces where the LHC with the integrated luminosity of 3000 fb−1 cannot reach. It is emphasized that the complementary study at the LHC and the ILC is useful not only to survey additional Higgs bosons at the TeV scale, but also to discriminate types of Yukawa interaction in the 2HDM
Report of the Working Group on Photon and Weak Boson Production
Baur, Ulrich; Diehl, H T; Errede, D; Casey, D; Dorigo, T; Huston, J; Owens, J; Womersley, J; Apanasevich, L; Begel, M; Gershtein, Yu; Kelly, M; Kuhlmann, S E; Leone, S; Partos, D S; Rainwater, D L; Sakumoto, W; Steinbruck, G; Zielinski, M; Zutshi, V
2000-01-01
This report discusses physics issues which can be addressed in photon and weak boson production in Run II at the Tevatron. The current understanding and the potential of Run II to expand our knowledge of direct photon production in hadronic collisions is discussed. We explore the prospects for using the W-boson cross section to measure the integrated luminosity, improving the measurement of the W and Z boson transverse momentum distributions, the Z -> b\\bar b signal, and the lepton angular distribution in W decays. Finally, we consider the prospects for measuring the trilinear gauge boson couplings in Run II.
DEFF Research Database (Denmark)
Korsgaard, Steffen; Sassmannshausen, Sean Patrick
2015-01-01
In this chapter we explore four alternatives to the dominant discovery view of entrepreneurship; the development view, the construction view, the evolutionary view, and the Neo-Austrian view. We outline the main critique points of the discovery presented in these four alternatives, as well as their...... central concepts and conceptualization of the entrepreneurial function. On this basis we discuss three central themes that cut across the four alternatives: process, uncertainty, and agency. These themes provide new foci for entrepreneurship research and can help to generate new research questions and...
He, Hong-Jian
1998-08-01
We review the recent progress in studying the anomalous electroweak quartic gauge boson couplings (QGBCs) at the LHC and the next generation high energy e±e- linear colliders (LCs). The main focus is put onto the strong electroweak symmetry breaking scenario in which the non-decoupling guarantees sizable new physics effects for the QGBCs. After commenting upon the current low energy indirect bounds and summarizing the theoretical patterns of QGBCs predicted by the typical resonance/non-resonance models, we review our systematic model-independent analysis on bounding them via WW-fusion and WWZ/ZZZ-production. The interplay of the two production mechanisms and the important role of the beam-polarization at the LCs are emphasized. The same physics may be similarly and better studied at a multi-TeV muon collider with high luminosity.
International Nuclear Information System (INIS)
This is a pedagogical introduction to the general technique of bosonization of one-dimensional systems starting from scratch and assuming very little besides basic quantum mechanics and second quantization. The formalism is developed in a self-contained fashion and applied to the spinless and spin-1/2 Luttinger models, working out both single and two particle correlation functions. The implications of these results for the specific cases of the (anisotropic) Heisenberg and the Hubbard models are discussed. Although everything in these notes can be found in the published literature, detailed and explicit calculations of most of the results are given, which may prove useful to beginning graduate students or researchers in this area. (author)
Cele, Favourite N; Ramesh, Muthusamy; Soliman, Mahmoud Es
2016-01-01
A novel virtual screening approach is implemented herein, which is a further improvement of our previously published "target-bound pharmacophore modeling approach". The generated pharmacophore library is based only on highly contributing amino acid residues, instead of arbitrary pharmacophores, which are most commonly used in the conventional approaches in literature. Highly contributing amino acid residues were distinguished based on free binding energy contributions obtained from calculation from molecular dynamic (MD) simulations. To the best of our knowledge; this is the first attempt in the literature using such an approach; previous approaches have relied on the docking score to generate energy-based pharmacophore models. However, docking scores are reportedly unreliable. Thus, we present a model for a per-residue energy decomposition, constructed from MD simulation ensembles generating a more trustworthy pharmacophore model, which can be applied in drug discovery workflow. This work is aimed at introducing a more rational approach to the field of drug design, rather than comparing the validity of this approach against those previously reported. We recommend additional computational and experimental work to further validate this approach. This approach was used to screen for potential reverse transcriptase inhibitors using the pharmacophoric features of compound GSK952. The complex was subjected to docking, thereafter, MD simulation confirmed the stability of the system. Experimentally determined inhibitors with known HIV-reverse transcriptase inhibitory activity were used to validate the protocol. Two potential hits (ZINC46849657 and ZINC54359621) showed a significant potential with regard to free binding energy. Reported results obtained from this work confirm that this new approach is favorable in the future of the drug design industry. PMID:27114700
Cele, Favourite N; Ramesh, Muthusamy; Soliman, Mahmoud ES
2016-01-01
A novel virtual screening approach is implemented herein, which is a further improvement of our previously published “target-bound pharmacophore modeling approach”. The generated pharmacophore library is based only on highly contributing amino acid residues, instead of arbitrary pharmacophores, which are most commonly used in the conventional approaches in literature. Highly contributing amino acid residues were distinguished based on free binding energy contributions obtained from calculation from molecular dynamic (MD) simulations. To the best of our knowledge; this is the first attempt in the literature using such an approach; previous approaches have relied on the docking score to generate energy-based pharmacophore models. However, docking scores are reportedly unreliable. Thus, we present a model for a per-residue energy decomposition, constructed from MD simulation ensembles generating a more trustworthy pharmacophore model, which can be applied in drug discovery workflow. This work is aimed at introducing a more rational approach to the field of drug design, rather than comparing the validity of this approach against those previously reported. We recommend additional computational and experimental work to further validate this approach. This approach was used to screen for potential reverse transcriptase inhibitors using the pharmacophoric features of compound GSK952. The complex was subjected to docking, thereafter, MD simulation confirmed the stability of the system. Experimentally determined inhibitors with known HIV-reverse transcriptase inhibitory activity were used to validate the protocol. Two potential hits (ZINC46849657 and ZINC54359621) showed a significant potential with regard to free binding energy. Reported results obtained from this work confirm that this new approach is favorable in the future of the drug design industry. PMID:27114700
Directory of Open Access Journals (Sweden)
Cele FN
2016-04-01
Full Text Available Favourite N Cele, Muthusamy Ramesh, Mahmoud ES Soliman Molecular Modelling and Drug Design Research Group, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa Abstract: A novel virtual screening approach is implemented herein, which is a further improvement of our previously published “target-bound pharmacophore modeling approach”. The generated pharmacophore library is based only on highly contributing amino acid residues, instead of arbitrary pharmacophores, which are most commonly used in the conventional approaches in literature. Highly contributing amino acid residues were distinguished based on free binding energy contributions obtained from calculation from molecular dynamic (MD simulations. To the best of our knowledge; this is the first attempt in the literature using such an approach; previous approaches have relied on the docking score to generate energy-based pharmacophore models. However, docking scores are reportedly unreliable. Thus, we present a model for a per-residue energy decomposition, constructed from MD simulation ensembles generating a more trustworthy pharmacophore model, which can be applied in drug discovery workflow. This work is aimed at introducing a more rational approach to the field of drug design, rather than comparing the validity of this approach against those previously reported. We recommend additional computational and experimental work to further validate this approach. This approach was used to screen for potential reverse transcriptase inhibitors using the pharmacophoric features of compound GSK952. The complex was subjected to docking, thereafter, MD simulation confirmed the stability of the system. Experimentally determined inhibitors with known HIV-reverse transcriptase inhibitory activity were used to validate the protocol. Two potential hits (ZINC46849657 and ZINC54359621 showed a significant potential with regard to free binding energy. Reported results obtained from
Top quark and Higgs boson masses in supersymmetric models
International Nuclear Information System (INIS)
We study the implications for bounds on the top quark pole mass mt in models with low scale supersymmetry following the discovery of the Standard Model-like Higgs boson. In the minimal supersymmetric standard model, we find that mt≥164 GeV, if the light CP even Higgs boson mass mh=125±2 GeV. We also explore the top quark and Higgs boson masses in two classes of supersymmetric SO(10) models with t-b-τ Yukawa coupling unification at MGUT. In particular, assuming SO(10) compatible non-universal gaugino masses, setting mh=125 GeV and requiring 5% or better Yukawa unification, we obtain the result 172 GeV≤mt≤175 GeV. Conversely, demanding 5% or better t-b-τ Yukawa unification and setting mt=173.2 GeV, the Higgs boson mass is predicted to lie in the range 122 GeV≤mh≤126 GeV
Higgs boson pizza day | 4 July 2016 | Restaurant 1
2016-01-01
Four years after the historic announcement of the discovery of the Higgs boson at CERN, a collaboration between INFN and CERN has declared 4 July 2016 “Higgs Boson Pizza Day”. The Novae Restaurant 1 at CERN will offer two special “Higgs Boson Pizzas” (one vegetarian and one ham and cheese), from 11.30 a.m. to 2.15 p.m., for the usual pizza price. The idea was born in Naples (where else?), the hometown of Pierluigi Paolucci, who - while chatting with INFN president Fernando Ferroni - realised the striking resemblance between Higgs boson event displays and the delicious pizzas in front of them. A specially designed pizza was then created by the chef of the historic “Ettore” pizzeria in St. Lucia, in time for the opening of an Art&Science exhibition on 15 September 2015 in Naples. The owner of the restaurant, Ms Iolanda Canale, has been invited by INFN to come to CERN and help Novae in the preparation of 400 pizzas on thi...
How to Detect `Decoupled' Heavy Supersymmetric Higgs Bosons
Bisset, Mike; Li, Jun
2007-01-01
Heretofore neglected decay modes of heavy MSSM Higgs bosons into a variety of neutralino pairs may push the LHC discovery reach for these crucial elements of an extended Higgs sector to nearly the TeV-scale -- if sparticle-sector MSSM input parameters are favorable. This is well into the so-called decoupling region, including moderate to low tan(beta) values, where no known signals exist for said heavy Higgs bosons via decays involving solely SM daughter particles, and the lighter h^0 mimics the lone SM Higgs boson. While the expanse of the Higgs to sparticle discovery region is sensitive to a number of MSSM parameters, including in particular those for the sleptons, its presence is primarily linked to the gaugino inputs -- in fact, to just one parameter, M_2, if gaugino unification is invoked. Thus consideration of high vs. low M_2 realms in the MSSM should be placed on a par with the extensive consideration already given to high vs. low tan(beta) regimes.
LHC signals of a BLSSM CP-even Higgs boson
Hammad, A; Moretti, S
2016-01-01
We study the scope of the Large Hadron Collider in accessing a neutral Higgs boson of the $B-L$ Supersymmetric Standard Model. After assessing the surviving parameter space configurations following the Run 1 data taking, we investigate the possibilities of detecting this object during Run 2. For the model configurations in which the mixing between such a state and the discovered Standard Model-like Higgs boson is non-negligible, there exist several channels enabling its discovery over a mass range spanning from $\\approx 140$ to $\\approx$ 500 GeV. For a lighter Higgs state, with mass of order 140 GeV, three channels are accessible: $\\gamma\\gamma$, $Z\\gamma$ and $ZZ$, wherein the $Z$ boson decays leptonically. For a heavier Higgs state, with mass above 250 GeV (i.e., twice the mass of the Higgs state discovered in 2012), the hallmark signature is its decay in two such 125 GeV scalars, $h'\\to hh$, where $hh\\to b\\bar b \\gamma\\gamma$. In all such cases, significances above discovery can occur for already planned l...
Supersymmetric Decays of the Z' Boson
Chang, Chun-Fu; Yuan, Tzu-Chiang
2011-01-01
The decay of the Z' boson into supersymmetric particles is studied. We investigate how these supersymmetric modes affect the current limits from the Tevatron and project the expected sensitivities at the LHC. Employing three representative supersymmetric Z' models, namely, E_6, U(1)_{B-L}, and the sequential model, we show that the current limits of the Z' mass from the Tevatron could be reduced substantially due to the weakening of the branching ratio into leptonic pairs. The mass reach for the E_6 Z' bosons is about 1.3-1.5 TeV at the LHC-7 (1 fb^{-1}), about 2.5 - 2.6 TeV at the LHC-10 (10 fb^{-1}), and about 4.2 - 4.3 TeV at the LHC-14 (100 fb^{-1}). A similar mass reach for the U(1)_{B-L} Z' is also obtained. We also examine the potential of identifying various supersymmetric decay modes of the Z' boson because it may play a crucial role in the detailed dynamics of supersymmetry breaking.
The Higgs Boson as a Window to Beyond the Standard Model
Energy Technology Data Exchange (ETDEWEB)
Vega-Morales, Roberto [Northwestern Univ., Evanston, IL (United States)
2013-08-01
The recent discovery of a Higgs boson at the LHC with properties resembling those predicted by the Standard Model (SM) gives strong indication that the final missing piece of the SM is now in place. In particular, the mechanism responsible for Electroweak Symmetry Breaking (EWSB) and generating masses for the Z and W vector bosons appears to have been established. Even with this amazing discovery there are still many outstanding theoretical and phenomenological questions which suggest that there must be physics Beyond the Standard Model (BSM). As we investigate in this thesis, the Higgs boson offers the exciting possibility of acting as a window to this new physics through various avenues which are experimentally testable in the coming years. We investigate a subset of these possibilities and begin by discussing them briefly below before a detailed examination in the following chapters.
Zhou, Meng; Zhong, Lei; Xu, Wanying; Sun, Yifan; Zhang, Zhaoyue; Zhao, Hengqiang; Yang, Lei; Sun, Jie
2016-01-01
Deregulation of long non-coding RNAs (lncRNAs) expression has been proven to be involved in the development and progression of cancer. However, expression pattern and prognostic value of lncRNAs in breast cancer recurrence remain unclear. Here, we analyzed lncRNA expression profiles of breast cancer patients who did or did not develop recurrence by repurposing existing microarray datasets from the Gene Expression Omnibus database, and identified 12 differentially expressed lncRNAs that were closely associated with tumor recurrence of breast cancer patients. We constructed a lncRNA-focus molecular signature by the risk scoring method based on the expression levels of 12 relapse-related lncRNAs from the discovery cohort, which classified patients into high-risk and low-risk groups with significantly different recurrence-free survival (HR = 2.72, 95% confidence interval 2.07-3.57; p = 4.8e-13). The 12-lncRNA signature also represented similar prognostic value in two out of three independent validation cohorts. Furthermore, the prognostic power of the 12-lncRNA signature was independent of known clinical prognostic factors in at least two cohorts. Functional analysis suggested that the predicted relapse-related lncRNAs may be involved in known breast cancer-related biological processes and pathways. Our results highlighted the potential of lncRNAs as novel candidate biomarkers to identify breast cancer patients at high risk of tumor recurrence. PMID:27503456
Molasses or Crowds: Making Sense of the Higgs Boson with Two Popular Analogies
Alsop, S.; Beale, S.
2013-01-01
The recent discovery of the Higgs boson at the Large Hadron Collider (LHC) has contributed to a surge of interest in particle physics and science education in general. Given the conceptual difficulty of the phenomenon in question, it is inevitable that teachers and science communicators rely on analogies to explain the Higgs physics and its…
International Nuclear Information System (INIS)
It was 20 years ago this month that particle physicists caught their first glimpse of the W boson. Now they have measured its mass so precisely that the Standard Model is facing an unprecedented challenge. (U.K.)
Spectroscopy of family gauge bosons
International Nuclear Information System (INIS)
Spectroscopy of family gauge bosons is investigated based on a U(3) family gauge boson model proposed by Sumino. In his model, the family gauge bosons are in mass eigenstates in a diagonal basis of the charged lepton mass matrix. Therefore, the family numbers are defined by (e1,e2,e3)=(e,μ,τ), while the assignment for quark sector are free. For possible family-number assignments (q1,q2,q3), under a constraint from K0–K¯0 mixing, we investigate possibilities of new physics, e.g. production of the lightest family gauge boson at the LHC, μ−N→e−N, rare K and B decays, and so on.
Is geometry bosonic or fermionic?
Hughes, Taylor L
2011-01-01
It is generally assumed that the gravitational field is bosonic. Here we show that a simple propagating torsional theory can give rise to localized geometric structures that can consistently be quantized as fermions under exchange. To demonstrate this, we show that the model can be formally mapped onto the Skyrme model of baryons, and we use well-known results from Skyrme theory. This begs the question: {\\it Is geometry bosonic or fermionic (or both)?}
From Bosonic Strings to Fermions
Sidharth, B. G.
2006-01-01
Early string theory described Bosonic particles at the real life Compton scale. Later developments to include Fermions initiated by Ramond and others have lead through Quantum Super Strings to M-theory operating at the as yet experimentally unattainable Planck scale. We describe an alternative route from Bosonic Strings to Fermions, by directly invoking a non commutative geometry, an approach which is closer to experiment.
The model-independent analysis for Higgs boson
Indian Academy of Sciences (India)
M D NAIMUDDIN; SHIVALI MALHOTRA
2016-09-01
The discovery of a 125 GeV particle, announced by the ATLAS and CMS Collaborations on July 04, 2012, is one of the most important events in the recent history of particle physics. This particle could be the last missing particle of the Standard Model of particle physics or it could be the beginning of the long list of particles predicted by the physics beyond the Standard Model. Before we jump to make the final conclusion about this particle, it is imperative to study all the properties of this newly discovered particle. Since the model-dependentanalyses always have this danger of being biased, we can perform a model-independent search for the Higgs boson and also check if the 125 GeV particle is indeed the Standard Model Higgs boson or a particle belonging to the physics beyond the Standard Model.
Energy Technology Data Exchange (ETDEWEB)
Yazgan, E.; /Middle East Tech. U., Ankara /Fermilab; Damgov, J.; /Sofiya, Inst. Nucl. Res. /Fermilab; Akchurin, N.; /Texas Tech.; Genchev, V.; /Sofiya, Inst. Nucl. Res.; Green, D.; /Fermilab; Kunori, S.; /Maryland U.; Schmitt, M.; /Northwestern U.; Wu, W.; /Fermilab; Zeyrek, M.T.; /Middle East Tech. U., Ankara
2007-06-01
We present the potential for discovering the Standard Model Higgs boson produced by the vector-boson fusion mechanism. We considered the decay of Higgs bosons into the W{sup +}W{sup -} final state, with both W-bosons subsequently decaying leptonically. The main background is t{bar t} with one or more jets produced. This study is based on a full simulation of the CMS detector, and up-to-date reconstruction codes. The result is that a signal of 5{sigma} significance can be obtained with an integrated luminosity of 12 - 72 fb{sup -1} for Higgs boson masses between 130 < m{sub H} < 200 GeV . In addition, the major background can be measured directly to 7% from the data with an integrated luminosity of 30 fb{sup -1}. In this study, we suggested a method to obtain information in Higgs mass using the transverse mass distributions.
Lenzi, Bruno; Nicolaidou, Rosy
2010-01-01
The central subject of this thesis is the evaluation of the discovery potential of the Higgs boson through its decay into four leptons (electrons and muons) in the ATLAS experiment installed at the Large Hadron Collider (LHC). The LHC was designed to accelerate proton beams at a center of mass energy of 14~TeV and started its physics program with 7~TeV collisions in the beginning of 2010. An inclusive analysis involving all the production modes and an exclusive one aiming at production through vector boson fusion (VBF), studied for the first time in the collaboration, are presented. Both are capable of discovering the Higgs boson after a few years of LHC operation, with integrated luminosities of 30~fb$^{-1}$. The first one covers most part of a Higgs mass window from 130 to 500~GeV. The second one concentrates on masses around 180~GeV and above, exploiting the presence of high energy jets with large separations in pseudo-rapidity to increase the signal over background ratio. An important part of the document...
Analytic boosted boson discrimination
Larkoski, Andrew J.; Moult, Ian; Neill, Duff
2016-05-01
Observables which discriminate boosted topologies from massive QCD jets are of great importance for the success of the jet substructure program at the Large Hadron Collider. Such observables, while both widely and successfully used, have been studied almost exclusively with Monte Carlo simulations. In this paper we present the first all-orders factorization theorem for a two-prong discriminant based on a jet shape variable, D 2, valid for both signal and background jets. Our factorization theorem simultaneously describes the production of both collinear and soft subjets, and we introduce a novel zero-bin procedure to correctly describe the transition region between these limits. By proving an all orders factorization theorem, we enable a systematically improvable description, and allow for precision comparisons between data, Monte Carlo, and first principles QCD calculations for jet substructure observables. Using our factorization theorem, we present numerical results for the discrimination of a boosted Z boson from massive QCD background jets. We compare our results with Monte Carlo predictions which allows for a detailed understanding of the extent to which these generators accurately describe the formation of two-prong QCD jets, and informs their usage in substructure analyses. Our calculation also provides considerable insight into the discrimination power and calculability of jet substructure observables in general.
Energy Technology Data Exchange (ETDEWEB)
Schmitz, Martin
2011-05-15
A study of the expected sensitivity of the ATLAS experiment to discover the Standard Model Higgs boson produced via vector boson fusion (VBF) and its decay to H{yields} {tau}{tau} {yields} ll + 4{nu} is presented. The study is based on simulated proton-proton collisions at a centre-of-mass energy of 14 TeV. For the rst time the discovery potential is evaluated in the presence of additional proton-proton interactions (pile-up) to the process of interest in a complete and consistent way. Special emphasis is placed on the development of background estimation techniques to extract the main background processes Z{yields} {tau}{tau} and t anti t production using data. The t anti t background is estimated using a control sample selected with the VBF analysis cuts and the inverted b-jet veto. The dominant background process Z {yields} {tau}{tau} is estimated using Z{yields} {mu}{mu} events. Replacing the muons of the Z{yields} {mu}{mu} event with simulated {tau}-leptons, Z {yields} {tau}{tau} events are modelled to high precision. For the replacement of the Z boson decay products a dedicated method based on tracks and calorimeter cells is developed. Without pile-up a discovery potential of 3{sigma} to 3.4{sigma} in the mass range 115 GeV
Excited Weak Bosons and Dark Matter
Fritzsch, Harald
2016-01-01
The weak bosons are bound states of new constituents, the haplons. The p-wave excitations are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be the excited weak tensor boson. The stable fermion, consisting of three haplons, provides the dark matter in our universe.
Electrophobic Scalar Boson and Muonic Puzzles
Liu, Yu-Sheng; Miller, Gerald A
2016-01-01
A new scalar boson which couples to the muon and proton can simultaneously solve the proton radius puzzle and the muon anomalous magnetic moment discrepancy. Using a variety of measurements, we constrain the mass of this scalar and its couplings to the electron, muon, neutron, and proton. Making no assumptions about the underlying model, these constraints and the requirement that it solve both problems limit the mass of the scalar to between about 100 keV and 100 MeV. We identify two unexplored regions in the coupling constant-mass plane. Potential future experiments and their implications for theories with mass-weighted lepton couplings are discussed.
On the spin of gravitational bosons
Ahluwalia, D V; Kirchbach, M
2002-01-01
We unearth spacetime structure of massive vector bosons, gravitinos, and gravitons. While the curvatures associated with these particles carry a definite spin, the underlying potentials cannot be, and should not be, interpreted as single spin objects. For instance, we predict that a spin measurement in the rest frame of a massive gravitino will yield the result 3/2 with probability one half, and 1/2 with probability one half. The simplest scenario leaves the Riemannian curvature unaltered; thus avoiding conflicts with classical tests of the theory of general relativity. However, the quantum structure acquires additional contributions to the propagators, and it gives rise to additional phases.
Precision Higgs boson measurement at CLIC
Pandurovic, Mila
2016-01-01
The design of the next generation collider in high energy physics will primarily focus on the possibility to achieve high precision of the measurements of interest. The necessary precision limits are set, in the first place, by the measurement of the Higgs boson but also by measurements that are sensitive to signs of New Physics. The Compact Linear Collider (CLIC) is an attractive option for a future multi-TeV linear electron-positron collider, with the potential to cover a rich physics program with high precision. In this lecture the CLIC accelerator, detector and backgrounds will be presented with emphesis on the capabilities of CLIC for precision Higgs physics.
Gelmini, Graciela B
2014-01-01
The last particle that completes the Standard Model of Elementary Particles, the most sophisticated theory of nature in human history, was discovered in 2012. Although the present formulation of the theory comes from the 1960s and 70s, it incorporates all discoveries that thousands of scientists made about elementary particles and their interactions (except for gravity) since the 1700s. Even if briefly, here we review the development of the major concepts included in the theory and explain the relevance of the new particle and the mechanism for which F. Englert and P. Higgs received the Nobel Prize in Physics 2013
Degenerate states in the scalar boson spectrum. Is the Higgs Boson a Twin ?
Stech, Berthold
2013-01-01
The extension of the standard model to $SU(3)_L\\times SU(3)_R \\times SU(3)_C$ is considered. Spontaneous symmetry breaking requires two $(3^*, 3, 1)$ Higgs field multiplets with a strong hierarchical structure of their vacuum expectation values. An invariant potential is constructed to provide for these vacuum expectation values. This potential gives masses to all scalar fields apart from the 15 Goldstone bosons. In case there exists a one-to-one correspondence between the vacuum expectation values of the two field multiplets, the scalar boson spectrum contains degenerate eigenstates. The lowest eigenstate has a mass near 123 GeV close to the Higgs-like particle discovered at the LHC. In one class of solutions this lowest state is a nearly degenerate twin state. Each member is a superposition of fields from both multiplets with about equal strength. The twins are non identical twins, namely different combinations of a conventional Higgs and a Higgs field which is not coupled to fermions, only to gauge bosons....
International Nuclear Information System (INIS)
The framework of the studies presented in this thesis is the search for the Higgs boson in the 4 leptons channel with the ATLAS experiment. The Higgs boson is a particle whose existence is predicted by the Electroweak theory but has not yet been observed, and its search is one of the main research subjects at the LHC, since its discovery would complete the Standard Model. First, a study of the electromagnetic calorimeter level-one trigger system is presented. Based on data recorded in 2010, it has helped improve the behaviour of the system for very high energy deposits. It has also provided trigger efficiency uncertainties for the analyses searching for W0 and Z0 bosons. Then the measurement with 2010 data of the cross-section of b-jets production in association with Z bosons is discussed. This measurement, which is in agreement with Standard Model computations, constrains one of the important backgrounds in the search for the Higgs boson in 4 leptons: namely the production of a Z boson and b-quark pair. In order to increase the selection efficiency for the Higgs boson decaying into four electrons, an improved electron reconstruction is studied. Its validation is presented for electrons from heavy flavour decays. The search analysis of the Higgs boson in the 4 lepton channel is then described, and several possibilities are studied, to increase the sensitivity of the analysis for low-mass searches. (author)
Search for the Higgs boson in the di-photon decay with the Atlas detector at LHC
International Nuclear Information System (INIS)
The goal of this thesis is the preparation of the Higgs boson search in its di-photon decay at LHC with the ATLAS detector. The issues that have been studied deal with the Higgs→ γγ vertex reconstruction, with the electromagnetic calorimeter and the inner detector, and the di-photon invariant mass resolution. Different simulations of the ATLAS detector and the effects of additional material and of detector misalignments have been studied. Issues concerning the statistical significance calculation have also been discussed and the discovery potential has been evaluated. A part if this thesis is done with CSC data, that use the most recent detector simulation and new reconstruction methods. Every step of the signal and background treatment has been discussed. We finally evaluate that with an integrated luminosity of 10 fb-1 we will be able to see a Higgs→ γγ signal with a statistical significance of 3 σ. (author)
Zhu, S
2006-01-01
The $O$(MeV) spin-1 U-boson has been proposed to mediate the interaction among electron-positron and $O$(MeV) dark matter, in order to account for the 511 keV $\\gamma$-ray observation by SPI/INTEGRAL. In this paper the observability of such kind of U-boson at BESIII is investigated through the processes $e^+e^- \\to U \\gamma$ and $e^+e^- \\to J/\\Psi \\to e^+e^- U$. We find that BESIII and high luminosity B-factories have the comparable capacity to detect such U-boson. If U-boson decays mainly into dark matter, i.e. invisibly, BESIII can measure the coupling among U-boson and electron-positron $g_{eR}$ (see text) down to $O(10^{-5})$, and cover large parameter space which can account for 511 keV $\\gamma$-ray observation. On the other hand, provided that U decays mainly into electron-positron, BESIII can detect $g_{eR}$ down to $O(10^{-3})$, and it is hard to explore 511 keV $\\gamma$-ray measurement allowed parameter space due to the irreducible QED backgrounds.
Spin models and boson sampling
Garcia Ripoll, Juan Jose; Peropadre, Borja; Aspuru-Guzik, Alan
Aaronson & Arkhipov showed that predicting the measurement statistics of random linear optics circuits (i.e. boson sampling) is a classically hard problem for highly non-classical input states. A typical boson-sampling circuit requires N single photon emitters and M photodetectors, and it is a natural idea to rely on few-level systems for both tasks. Indeed, we show that 2M two-level emitters at the input and output ports of a general M-port interferometer interact via an XY-model with collective dissipation and a large number of dark states that could be used for quantum information storage. More important is the fact that, when we neglect dissipation, the resulting long-range XY spin-spin interaction is equivalent to boson sampling under the same conditions that make boson sampling efficient. This allows efficient implementations of boson sampling using quantum simulators & quantum computers. We acknowledge support from Spanish Mineco Project FIS2012-33022, CAM Research Network QUITEMAD+ and EU FP7 FET-Open Project PROMISCE.
Energy Technology Data Exchange (ETDEWEB)
Tisserand, V. [Paris-11 Univ., 91 - Orsay (France). Lab. de l' Accelerateur Lineaire]|[Universite de Paris Sud, 91 - Orsay (France)
1997-02-03
The two photon decay channel is the most clear and promising way to detect a Higgs boson of an intermediate mass between 80 GeV/c{sup 2} and 150 GeV/c{sup 2} at the future large proton collider of CERN (LHC). As the Higgs mass is narrow in this range, the observation of this channel relies on the performance of the electromagnetic calorimeter. A full simulation study has been performed to evaluate the discovery potential of the ATLAS detector. The results of this simulation have been confirmed by beam tests with a prototype. This simulation includes different contributions such as energy resolution sampling term, electronic and pile-up noise, global constant term and angular measurement of the two photon opening angle. The levels of the irreducible background from prompt di-photon production and the reducible background from jets with isolated leading neutrals pions have been estimated, taking into account the rejection capability of the detector. After the computation of the two photon invariant mass resolution, and the evaluation of signal and background rates, the discovery potential of the Higgs boson with the ATLAS detector was calculated. The Higgs can be discovered at five sigma confidence level after less than a year of data taking at LHC with the nominal luminosity of 10{sup 34} cm{sup -2}.s{sup -1} if the Higgs mass is between 100 GeV/c{sup 2} and 150 GeV/c{sup 2}. The Higgs mass window between 80 GeV/c{sup 2} and 150 GeV/c{sup 2} will be covered with an integrated luminosity of 3.10{sup 5} pb{sup -1}. In the case of the Minimal Supersymmetric Model (MSSM) the plane (m{sub A{sup 0}}, tan({beta})) will be fully explored if m{sub A{sup 0}} > 175 GeV/c{sup 2}. (author)
Iron K$\\alpha$ line of boson stars
Cao, Zheng; Zhou, Menglei; Bambi, Cosimo; Herdeiro, Carlos A R; Radu, Eugen
2016-01-01
The present paper is a sequel to our previous work [Y. Ni et al., JCAP 1607, 049 (2016)] in which we studied the iron K$\\alpha$ line expected in the reflection spectrum of Kerr black holes with scalar hair. These metrics are solutions of Einstein's gravity minimally coupled to a massive, complex scalar field. They form a continuous bridge between a subset of Kerr black holes and a family of rotating boson stars depending on one extra parameter, the dimensionless scalar hair parameter $q$, ranging from 0 (Kerr black holes) to 1 (boson stars). Here we study the limiting case $q=1$, corresponding to rotating boson stars. For comparison, spherical boson stars are also considered. We simulate observations with XIS/Suzaku. Using the fact that current observations are well fit by the Kerr solution and thus requiring that acceptable alternative compact objects must be compatible with a Kerr fit, we find that some boson star solutions are relatively easy to rule out as potential candidates to explain astrophysical bla...
A Z' Boson and the Higgs Boson Mass
Chanowitz, Michael S.
2008-01-01
The Standard Model fit prefers values of the Higgs boson mass that are below the 114 GeV direct lower limit from LEP II. The discrepancy is acute if the 3.2 sigma disagreement for the effective weak interaction mixing angle from the two most precise measurements is attributed to underestimated systematic error. In that case the data suggests new physics to raise the predicted value of the Higgs mass. One of the simplest possibilities is a Z' boson, which would generically increase the predict...
Massive the Higgs boson and the greatest hunt in science
Sample, Ian
2013-01-01
Now fully updated -- this is the dramatic and gripping account of the greatest scientific discovery of our time. In the early 1960s, three groups of physicists, working independently in different countries, stumbled upon an idea that would change physics and fuel the imagination of scientists for decades. That idea was the Higgs boson -- to find it would be to finally understand the origins of mass -- the last building block of life itself. Now, almost 50 years later, that particle has finally been discovered.
Invisible decays of low mass Higgs bosons in supersymmetric models
Pandita, P. N.; Patra, Monalisa
2014-01-01
The discovery of a 126 GeV Higgs like scalar at the LHC along with the non observation of the supersymmetric particles, has in turn lead to constraining various supersymmetric models through the Higgs data. We here consider the case of both MSSM, as well its extension containing an additional chiral singlet superfield, NMSSM. We concentrate on the case where we identify the second lightest Higgs boson as the 126 GeV state discovered at the CERN LHC and consider the invisible decays of the low...
Boson spectra and correlations for thermal locally equilibrium systems
Sinyukov, Yu M
1999-01-01
The single- and multi- particle inclusive spectra for strongly inhomogeneous thermal boson systems are studied using the method of statistical operator. The thermal Wick's theorem is generalized and the analytical solution of the problem for an boost-invariant expanding boson gas is found. The results demonstrate the effects of inhomogeneity for such a system: the spectra and correlations for particles with wave-lengths larger than the system's homogeneity lengths change essentially as compared with the results based on the local Bose-Einstein thermal distributions. The effects noticeable grow for overpopulated media, where the chemical potential associated with violation of chemical equilibrium is large enough.
Dimensional structural constants from chiral and conformal bosonization of QCD
Andrianov, A A; Ebert, D; Mann, T F; Mann, Th. Feld
1997-01-01
We derive the dimensional non-perturbative part of the QCD effective ac= tion for scalar and pseudoscalar meson fields by means of chiral and conformal bosonization. The related structural coupling constants L_5 and L_8 of th= e chiral lagrangian are estimated using general relations which are valid i= n a variety of chiral bosonization models without explicit reference to model parameters. The asymptotics for large scalar fields in QCD is elaborated,= and model-independent constraints on dimensional coupling constants of the effective meson lagrangian are evaluated. We determine also the interacti= on between scalar quarkonium and the gluon density and obtain the scalar glueball-quarkonium potential.
PDF uncertainties at large x and gauge boson production
Energy Technology Data Exchange (ETDEWEB)
Accardi, Alberto [Hampton U., JLAB
2012-10-01
I discuss how global QCD fits of parton distribution functions can make the somewhat separated fields of high-energy particle physics and lower energy hadronic and nuclear physics interact to the benefit of both. In particular, I will argue that large rapidity gauge boson production at the Tevatron and the LHC has the highest short-term potential to constrain the theoretical nuclear corrections to DIS data on deuteron targets necessary for up/down flavor separation. This in turn can considerably reduce the PDF uncertainty on cross section calculations of heavy mass particles such as W' and Z' bosons.
Boson spectra and correlations for thermal locally equilibrium systems
International Nuclear Information System (INIS)
The single- and multi-particle inclusive spectra for strongly inhomogeneous thermal boson systems are studied using the method of statistical operator. The thermal Wick's theorem is generalized and the analytical solution of the problem for a boost-invariant expanding boson gas is found. The results demonstrate the effects of inhomogeneity for such a system: the spectra and correlations for particles with wavelengths larger than the system's homogeneity lengths change essentially as compared with the results based on the local Bose-Einstein thermal distributions. The effects noticeably grow for overpopulated media, where the chemical potential associated with violation of chemical equilibrium is large enough. (author)
The mass spectrum of Diquark Boson in the color superconductor
Energy Technology Data Exchange (ETDEWEB)
Yamaguchi, K.; Miyamura, O. [Hiroshima Univ., Dept. of Physics, Higashi-Hiroshima, Hiroshima (Japan)
2000-08-01
In this work we apply the functional integral method to the study of the color superconducting phase and compute the mass spectrum of the Diquark Boson at finite temperature and nonzero chemical potential. We find the different aspect with QED superconductor. (author)
Inclusion of g boson in the microscopic sdgIBM and the g boson effect
International Nuclear Information System (INIS)
The inclusion of g boson in the microscopic sdgIBM is presented. The collectivity of g boson, the relationship between g boson properties and the strengths of the effective nucleon-nucleon interaction, and the influence of g boson on the sdIBM are discussed in detail
Light Front Boson Model Propagation
Institute of Scientific and Technical Information of China (English)
Jorge Henrique Sales; Alfredo Takashi Suzuki
2011-01-01
stract The scope and aim of this work is to describe the two-body interaction mediated by a particle (either the scalar or the gauge boson) within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x+ = 0 to x+ ＞ O. It corresponds to the definition of the time ordering operation in the light front time x+. We calculate the light-front Green's function for 2 interacting bosons propagating forward in x+. We also show how to write down the light front Green's function from the Feynman propagator and finally make a generalization to N bosons.
Energy Technology Data Exchange (ETDEWEB)
Hartmann, Betti, E-mail: b.hartmann@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany); Riedel, Jürgen, E-mail: j.riedel@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany); Faculty of Physics, University Oldenburg, 26111 Oldenburg (Germany); Suciu, Raluca, E-mail: r.suciu@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany)
2013-11-04
We construct boson stars in (4+1)-dimensional Gauss–Bonnet gravity. We study the properties of the solutions in dependence on the coupling constants and investigate in detail their properties. While the “thick wall” limit is independent of the value of the Gauss–Bonnet coupling, we find that the spiraling behaviour characteristic for boson stars in standard Einstein gravity disappears for large enough values of the Gauss–Bonnet coupling. Our results show that in this case the scalar field can not have arbitrarily high values of the scalar field at the center of the boson star and that it is hence impossible to reach the “thin wall” limit. Moreover, for large enough Gauss–Bonnet coupling we find a unique relation between the mass and the radius (qualitatively similar to those of neutron stars) which is not present in the Einstein gravity limit.
2003-01-01
Many people don't realise quite how much is going on at CERN. Would you like to gain first-hand knowledge of CERN's scientific and technological activities and their many applications? Try out some experiments for yourself, or pick the brains of the people in charge? If so, then the «Lundis Découverte» or Discovery Mondays, will be right up your street. Starting on May 5th, on every first Monday of the month you will be introduced to a different facet of the Laboratory. CERN staff, non-scientists, and members of the general public, everyone is welcome. So tell your friends and neighbours and make sure you don't miss this opportunity to satisfy your curiosity and enjoy yourself at the same time. You won't have to listen to a lecture, as the idea is to have open exchange with the expert in question and for each subject to be illustrated with experiments and demonstrations. There's no need to book, as Microcosm, CERN's interactive museum, will be open non-stop from 7.30 p.m. to 9 p.m. On the first Discovery M...
An introduction to boson-sampling
Gard, Bryan T; Motes, Keith R.; Olson, Jonathan P.; Rohde, Peter P.; Dowling, Jonathan P.
2014-01-01
Boson-sampling is a simplified model for quantum computing that may hold the key to implementing the first ever post-classical quantum computer. Boson-sampling is a non-universal quantum computer that is significantly more straightforward to build than any universal quantum computer proposed so far. We begin this chapter by motivating boson-sampling and discussing the history of linear optics quantum computing. We then summarize the boson-sampling formalism, discuss what a sampling problem is...
Vectorial versus axial goldstone bosons
International Nuclear Information System (INIS)
The Yukawa interactions of fermions with Goldstone bosons are given in closed form for an arbitrary renormalizable field theory to all orders of perturbation theory or for a general effective Lagrangian. Although the diagonal couplings are always pseudoscalar there is an important difference between spontaneously broken vector and axial-vector global symmetries. Compared to the axial case, the diagonal douplings of 'vectorial' Goldstone bosons to charged fermions are suppressed by mixing angles or appear only via radiative corrections involving gauge fields. This general result may be relevant for the problem of flavour symmetry breaking in composite models. (Author)
Boson stars in the centre of galaxies?
Schunck, Franz E
2008-01-01
We investigate the possible gravitational redshift values for boson stars with a self-interaction, studying a wide range of possible masses. We find a limiting value of z_lim \\simeq 0.687 for stable boson star configurations. We can exclude the direct observation of boson stars. X-ray spectroscopy is perhaps the most interesting possibility.
A generalization of boson normal ordering
International Nuclear Information System (INIS)
In this Letter we define generalizations of boson normal ordering. These are based on the number of contractions whose vertices are next to each other in the linear representation of the boson operator function. Our main motivation is to shed further light onto the combinatorics arising from algebraic and Fock space properties of boson operators
Introduction to the physics of Higgs bosons
Energy Technology Data Exchange (ETDEWEB)
Dawson, S.
1994-11-01
A basic introduction to the physics of the Standard Model Higgs boson is given. We discuss Higgs boson production in e{sup +}e{sup {minus}} and hadronic collisions and survey search techniques at future accelerators. The Higgs bosons of the minimal SUSY model are briefly considered. Indirect limits from triviality arguments, vacuum stability and precision measurements at LEP are also presented.
Charged Higgs Bosons in the LHCHXSWG
Heinemeyer, S
2014-01-01
Searches for charged Higgs bosons are an integral part of current and future investigations at the LHC. The LHC Higgs Cross Section Working Group (LHCHXSWG) was created to provide cross sections, branching ratios, analysis strategies etc. for Higgs boson searches at the LHC. We briefly review progress and results for charged Higgs bosons in and for the LHCHXSWG.
Introduction to the physics of Higgs bosons
International Nuclear Information System (INIS)
A basic introduction to the physics of the Standard Model Higgs boson is given. We discuss Higgs boson production in e+e- and hadronic collisions and survey search techniques at future accelerators. The Higgs bosons of the minimal SUSY model are briefly considered. Indirect limits from triviality arguments, vacuum stability and precision measurements at LEP are also presented
Twisted bosonization in two dimensional noncommutative spacetime
Haque, Asrarul
2012-01-01
We study the twisted bosonization of massive Thirring model to relate to sine-Gordon model in Moyal spacetime using twisted commutation relations. We obtain the relevant twisted bosonization rules. We show that there exists dual rela- tionship between twisted bosonic and fermionic operators. The strong-weak duality is also observed to be preserved as its commutative counterpart.
International Nuclear Information System (INIS)
The central subject of this thesis is the evaluation of the discovery potential of the Higgs boson through its decay into four leptons (electrons and muons) in the ATLAS experiment installed at the Large Hadron Collider (LHC). The LHC was designed to accelerate proton beams at a center of mass energy of 14 TeV and started its physics program with 7 TeV collisions in the beginning of 2010. An inclusive analysis involving all the production modes and an exclusive one aiming at production through vector boson fusion (VBF), studied for the first time in the collaboration, are presented. Both are capable of discovering the Higgs boson after a few years of LHC operation, with integrated luminosities of 30 fb-1. The first one covers most part of a Higgs mass window from 130 to 500 GeV. The second one concentrates on masses around 180 GeV and above, exploiting the presence of high energy jets with large separations in pseudo-rapidity to increase the signal over background ratio. An important part of the document is devoted to the reconstruction of muon isolation and energy loss in the ATLAS calorimeters. A software package that optimized the way of treating the energy deposits was developed and tested on simulated data and cosmic-ray events, leading to improvements in the muon momentum resolution and the distinction between muons from heavy quark and vector boson decays. As a consequence of the last result, one of the dominant backgrounds to the H → 4μ channel, Zb b-bar, is expected to be reduced by almost a factor of two. (author)
Low-Mass Higgs Bosons in the NMSSM and Their LHC Implications
Christensen, Neil D.; Han, Tao; Liu, Zhen; Su, Shufang
2013-01-01
We study the Higgs sector of the Next to Minimal Supersymmetric Standard Model (NMSSM) in light of the discovery of the SM-like Higgs boson at the LHC. We perform a broad scan over the NMSSM parameter space and identify the regions that are consistent with current Higgs search results at colliders. In contrast to the commonly studied "decoupling" scenario in the literature where the Minimal Supersymmetric Standard Model CP-odd Higgs boson mass is large mA >> mZ, we pay particular attention to...
Search for the Higgs boson in the ZH to llbb channel at CDF Run II
Energy Technology Data Exchange (ETDEWEB)
Efron, Jonathan Zvi; /Ohio State U.
2007-08-01
The Standard Model of particle physics is in excellent agreement with the observed phenomena of particle physics. Within the Standard Model, the weak and electromagnetic forces are successfully combined. However, this combination is only valid if the masses of the force carriers of the weak force, the Z and W bosons, are massless. In fact, these two particles are the second and third most massive observed elementary particles. Within the minimal Standard Model, the Higgs mechanism is introduced to reconcile this contradiction. Conclusive proof of this theory would come with the discovery of the Higgs boson.
Higgs boson flavor-changing neutral coupling and h→t*c decay at a muon collider
International Nuclear Information System (INIS)
We study the discovery potential of the flavor-changing neutral coupling (FCNC) htc of the Higgs boson and the top quark through the rare tree-body decay h→Wbc at muon colliders for a light Higgs boson with mass 114≤mh≤145 GeV. This decay mode may compete with the standard model (SM) background induced by the hWW coupling in some models with a tree-level htc coupling and with models that predict this coupling at the one-loop level in the range 10-2-10-1. A future muon collider could test the scalar FCNC decay t→hc via Higgs decay h→t*c→bW+c down to values of the coupling gtc=0.5[that are equivalent to BR(t→hc)∼5x10-3]. The LHC could probe values of gtc 1 order of magnitude smaller, unless other processes beyond the SM appear that through intense multijet activity may clutter the t→hc signal.
Rosendahl, Peter Lundgaard
One of the key questions in particle physics today, is the origin of the electroweak symmetry breaking. The answer to this question will most likely be solved with the data provided by the Large Hadron Collider which started colliding protons in 2008. Many ideas have been posed to how particles gain their masses. The most promising of these ideas is the Higgs mechanism which predicts the existence of a new massive scalar boson, the Higgs boson. Since the discovery of a new particle consistent with a Standard Model Higgs boson was made on July 4 by the ATLAS and CMS experiment, the solution for the puzzle of the electroweak symmetry breaking might be very near. However, in order to fully claim a discovery of the Standard Model Higgs boson, the new particle has to be proven to be a scalar boson and its decay has to be observed in both bosonic and fermionic final states with the corrected branching ratios predicted by the Standard Model. So far the new boson has only been seen in the bosonic gamma-gamma, ZZ and ...
Higgs boson physics and broken flavor symmetry -- LHC phenomenology
Berger, Edmond L
2014-01-01
The LHC implications are presented of a simplified model of broken flavor symmetry in which a new scalar (a flavon) emerges with mass in the TeV range. We summarize the influence of the model on Higgs boson physics, notably on the production cross section and decay branching fractions. Limits are obtained on the flavon $\\varphi$ from heavy Higgs boson searches at the LHC at 7 and 8 TeV. The branching fractions of the flavon are computed as a function of the flavon mass and the Higgs-flavon mixing angle. We explore possible discovery of the flavon at 14 TeV, particularly via the $\\varphi \\rightarrow Z^0Z^0$ decay channel in the $2\\ell2\\ell'$ final state, and through standard model Higgs boson pair production $\\varphi \\rightarrow hh$ in the $b\\bar{b}\\gamma\\gamma$ final state. The flavon mass range up to $500$ GeV could probed down to quite small values of the Higgs-flavon mixing angle with 100 fb$^{-1}$ of integrated luminosity at 14 TeV.
Baglio, Julien
2015-01-01
After the discovery of a Higgs boson in 2012 at the CERN Large Hadron Collider (LHC) the detailed study of its properties, and most importantly its couplings to other particles, has started. This is a very important task to be completed, in particular to test wether it is indeed the Higgs boson predicted by the Standard Model (SM). The precise study of the Higgs couplings to gauge bosons is of particular importance and requires as much information as possible. In this view this paper provides with the next-to-leading order (NLO) QCD corrections to the production cross sections and differential distributions of an SM Higgs boson in association with a pair of weak bosons $W^+W^-$, $W^\\pm Z$ and $ZZ$, matched with parton shower (PS) in the POWHEG-BOX framework. The NLO QCD corrections are found to be significant and PS effects are sizable at low $p_T$ in the jet differential distributions, as expected, while these effects are negligible in other distributions. We will also provide with a detailed study of the th...
Excited Weak Bosons and Dark Matter
Fritzsch, Harald
2016-01-01
The weak bosons are bound states of new constituents, the haplons. The p-wave excitations are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be the excited weak tenso...
Gravitational Stability of Boson Stars
Kusmartsev, Fjodor V; Schunck, Franz E
1991-01-01
We investigate the stability of general-relativistic boson stars by classifying singularities of differential mappings and compare it with the results of perturbation theory. Depending on the particle number, the star has the following regimes of behavior: stable, metastable, pulsation, and collapse.
Cheung, Kingman; Lee, Jae Sik; Park, Jubin; Tseng, Po-Yan
2015-01-01
We interpret the potential observation of the 750 GeV di-photon resonance at the LHC in models, in which an $SU(2)$ isospin-singlet scalar boson mixes with the Standard Model (SM) Higgs boson through an angle $\\alpha$. Allowing the singlet scalar boson to have renormalizable couplings to vector-like leptons and quarks, we can explain the large production cross section $\\sigma(H_2) \\times B(H_2 \\to \\gamma\\gamma)$ as well as the apparent large total width of the boson without conflicts from the results obtained by previous global fits to the SM Higgs boson data.
Search for Higgs bosons in the final state ZZ(*)-->llqq with the ATLAS detector at the LHC
AUTHOR|(INSPIRE)INSPIRE-00009427; Kourkoumelis, Christine; Polychronakos, Venetios
2016-04-25
This dissertation presents the search for Higgs-like bosons, in the decay mode H->ZZ(*)->llqq, using data collected with the ATLAS detector, at the CERN Large Hadron Collider (LHC). Despite the fact that this channel is mostly sensitive in the Higgs boson mass range above 200 GeV, before the discovery of the Standard Model Higgs boson the search was extended over the mass interval 120-180 GeV. Reasonable sensitivity is observed above 140 GeV. The search uses 4.7 ifb of proton–proton collision data, at a centre-of-mass energy of 7 TeV. After the discovery of the Higgs boson, the search focused towards the detection of additional, heavy Higgs bosons, in the mass range 200-1000 GeV. Proton–proton collision data, at a centre-of-mass energy of 8 TeV, are used, corresponding to an integrated luminosity of 20.3 ifb. Since no significant excess of events is observed over the Standard Model prediction, upper limits are set, at 95% confidence level (CL), on the production cross-section of a heavy Higgs boson times ...
The future (and past) of quantum theory after the Higgs boson: a quantum-informational viewpoint.
Plotnitsky, Arkady
2016-05-28
Taking as its point of departure the discovery of the Higgs boson, this article considers quantum theory, including quantum field theory, which predicted the Higgs boson, through the combined perspective of quantum information theory and the idea of technology, while also adopting anon-realistinterpretation, in 'the spirit of Copenhagen', of quantum theory and quantum phenomena themselves. The article argues that the 'events' in question in fundamental physics, such as the discovery of the Higgs boson (a particularly complex and dramatic, but not essentially different, case), are made possible by the joint workings of three technologies: experimental technology, mathematical technology and, more recently, digital computer technology. The article will consider the role of and the relationships among these technologies, focusing on experimental and mathematical technologies, in quantum mechanics (QM), quantum field theory (QFT) and finite-dimensional quantum theory, with which quantum information theory has been primarily concerned thus far. It will do so, in part, by reassessing the history of quantum theory, beginning with Heisenberg's discovery of QM, in quantum-informational and technological terms. This history, the article argues, is defined by the discoveries of increasingly complex configurations of observed phenomena and the emergence of the increasingly complex mathematical formalism accounting for these phenomena, culminating in the standard model of elementary-particle physics, defining the current state of QFT. PMID:27091170
The sensitivity of the Higgs boson branching ratios to the W boson width
Murray, William
2016-07-01
The Higgs boson branching ratio into vector bosons is sensitive to the decay widths of those vector bosons because they are produced with at least one boson significantly off-shell. Γ (H → VV) is approximately proportional to the product of the Higgs boson coupling and the vector boson width. ΓZ is well measured, but ΓW gives an uncertainty on Γ (H → WW) which is not negligible. The ratio of branching ratios, BR (H → WW) / BR (H → ZZ) measured by a combination of ATLAS and CMS at LHC is used herein to extract a width for the W boson of ΓW =1.8-0.3+0.4 GeV by assuming Standard Model couplings of the Higgs bosons. This dependence of the branching ratio on ΓW is not discussed in most Higgs boson coupling analyses.
The sensitivity of the Higgs boson branching ratios to the W boson width
Murray, William
2016-01-01
The Higgs boson branching ratio into vector bosons is sensitive to the decay widths of those vector bosons because they are produced with at least one boson significantly off-shell. Gamma(H to V V ) is approximately proportional to the product of the Higgs boson coupling and the vector boson width. Gamma Z is well known, but Gamma W gives an uncertainty on Gamma(H to W W ) which is not negligible. The ratio of branching ratios, BR(H to W W )/BR(H to ZZ) measured by a combination of ATLAS and CMS at LHC is used herein to extract a width for the W boson of Gamma W = 1.8+0.4-0.3 GeV by assuming Standard Model couplings of the Higgs bosons. This dependence of the branching ratio on Gamma W is not discussed in most Higgs boson coupling analyses.
Search for a neutral Higgs boson
Energy Technology Data Exchange (ETDEWEB)
Malmgren, T.G.M.
1997-04-01
The mass of the neutral Higgs boson cannot be predicted by models. Therefore, the particle is scanned for at different assumed masses. The search described here was done using data taken at the DELPHI detector in 1993. The Bjorken process was searched for where the decay of the Z{sup 0*} into two neutrinos was assumed. In order to reduce the background to a level where a discovery would be possible, an artificial feed-forward neural network was used. This led to a very good background rejection and high signal efficiency. An efficiency of around 30-50% was reached for a H{sup 0} mass ranging from 35-60 GeV/c{sup 2} leaving zero background events. One event was selected from the real data with a H{sup 0} mass of 27.5(3.6) GeV/c{sup 2}. These results were translated into a limit m{sub H}>58.3 GeV/c{sup 2} at 95% confidence level.
De-pinning of disordered bosonic chains
Vogt, N.; Cole, J. H.; Shnirman, A.
2016-05-01
We consider onset of transport (de-pinning) in one-dimensional bosonic chains with a repulsive boson–boson interaction that decays exponentially on large length-scales. Our study is relevant for (i) de-pinning of Cooper-pairs in Josephson junction arrays; (ii) de-pinning of magnetic flux quanta in quantum-phase-slip ladders, i.e. arrays of superconducting wires in a ladder-configuration that allow for the coherent tunneling of flux quanta. In the low-frequency, long wave-length regime these chains can be mapped onto an effective model of a one-dimensional elastic field in a disordered potential. The standard de-pinning theories address infinitely long systems in two limiting cases: (a) of uncorrelated disorder (zero correlation length); (b) of long range power-law correlated disorder (infinite correlation length). In this paper we study numerically chains of finite length in the intermediate case of long but finite disorder correlation length. This regime is of relevance for, e.g., the experimental systems mentioned above. We study the interplay of three length scales: the system length, the interaction range, the correlation length of disorder. In particular, we observe the crossover between the solitonic onset of transport in arrays shorter than the disorder correlation length to onset of transport by de-pinning for longer arrays.
Modeling small dark energy scale with quintessential pseudoscalar boson
Kim, Jihn E.(Department of Physics, Kyung Hee University, 26 Gyungheedaero, Dongdaemun-Gu, Seoul 130-701, Republic of Korea)
2013-01-01
Democracy among the same type of particles is a useful paradigm in studying masses and interactions of particles with supersymmetry(SUSY) or without SUSY. This simple idea predicts the presence of massless particles. We attempt to use one of these massless pseudoscalar particles as generating the cosmological dark energy(DE) potential. To achieve the extremely shallow potential of DE, the pseudoscalar boson is required not to couple to the QCD anomaly. So, we consider two pseudoscalars, one c...
The role of the top quark in the stability of the SM Higgs potential
Degrassi, Giuseppe
2014-01-01
I discuss the stability of the SM scalar potential in view of the discovery of a Higgs boson with mass around 125 GeV. The role played by the top quark mass in the choice between the full stability and the metastability conditions is analyzed in detail. The present experimental value of the top mass do not support the possibility that the SM potential is stable up to the Planck scale but favor an electroweak vacuum sufficiently long-lived to be metastable.
Inclusive Search for the SM Higgs Boson in the H->gammagamma channel at the LHC
Ganjour, Serguei
2008-01-01
A prospective for the inclusive search of the Standard Model Higgs boson in the decay channel H->gammagamm is presented with the CMS experiment at the LHC. The analysis relies on a strategy to determine the background characteristics and systematics from data. The strategy is applied to a Monte Model of the QCD background, with full simulation of the detector response. The discrimination between signal and background exploits information on photon isolation and kinematics. The resolution for the reconstructed Higgs boson mass profits from the excellent energy resolution of the CMS crystal calorimeter. A discovery significance above 5 sigma is expected at integrated LHC luminosities below 30 inverse femtobarn for Higgs boson masses below 140 GeV/c^2.
Mixed QCD-EW corrections for Higgs boson production at $e^+e^-$ colliders
Gong, Yinqiang; Xu, Xiaofeng; Yang, Li Lin
2016-01-01
Since the discovery of the Higgs boson at the Large Hadron Collider, a future electron-position collider has been proposed for precisely studying its properties. We investigate the production of the Higgs boson at such an $e^+e^-$ collider and calculate for the first time the mixed QCD-electroweak corrections to the total cross sections. We find that the $\\mathcal{O}(\\alpha\\alpha_s)$ corrections amount to a $1.2\\%$ increase of the cross section for a center-of-mass energy around 250 GeV. This is larger than the expected experimental accuracy and has to be included for extracting the properties of the Higgs boson from the measurements of the cross sections in the future.
Search for the Standard Model Higgs boson decaying into two photons
Spiezia, Aniello
2014-01-01
With the discovery of a Higgs boson, the standard model of particle physics has been successfully proved giving an answer to the origin of the masses issue, through the electroweak symmetry breaking mechanism. The Higgs decaying to two gammas is presented in this document. Although this channel has a low branching ratio, it provides a clean final state topology, with a peak that can be observed over the background, due mainly to irreducible direct diphoton production and to reducible gamma+jets and jet+jet. The analysis is performed using 2011 and 2012 datasets recorded by the CMS experiment from pp collisions at centre of mass energies of 7 TeV (5.1/fb) and 8 TeV (19.7/fb) and shows the presence of a new boson with a mass of about 125 GeV, that is in agreement with the standard model Higgs boson hypotheses.
3-Loop Corrections to the Higgs Boson Mass and Implications for Supersymmetry at the LHC
Feng, Jonathan L; Profumo, Stefano; Sanford, David
2013-01-01
In supersymmetric models with minimal particle content and without left-right squark mixing, the conventional wisdom is that the 125.6 GeV Higgs boson mass implies top squark masses of ~10 TeV, far beyond the reach of colliders. This conclusion is subject to significant theoretical uncertainties, however, and we provide evidence that it may be far too pessimistic. We evaluate the Higgs boson mass, including the dominant three-loop terms at O(\\alpha_t \\alpha_s^2), in currently viable models. For multi-TeV stops, the three-loop corrections can increase the Higgs boson mass by as much as 3 GeV and lower the required stop mass to 3 to 4 TeV, greatly improving prospects for supersymmetry discovery at the upcoming run of the LHC and its high-luminosity upgrade.
Top quark polarization as a probe of models with extra gauge bosons
International Nuclear Information System (INIS)
New heavy gauge bosons exist in many models of new physics beyond the standard model of particle physics. Discovery of these W(prime) and Z(prime) resonances and the establishment of their spins, couplings, and other quantum numbers would shed light on the gauge structure of the new physics. The measurement of the polarization of the SM fermions from the gauge boson decays would decipher the handedness of the coupling of the new states, an important relic of the primordial new physics symmetry. Since the top quark decays promptly, its decay preserves spin information. We show how decays of new gauge bosons into third generation fermions (W(prime) → tb, Z(prime) → t(bar t)) can be used to determine the handedness of the couplings of the new states and to discriminate among various new physics models.
Qin, Yang; The ATLAS collaboration
2015-01-01
After the discovery of the new particle consistent with the Higgs boson in 2012, the direct observation and measurement of the coupling of this particle to top quarks has become increasingly important. In this talk, a review of the latest ATLAS results on the search for the Higgs boson produced in association with top quarks, ttH, is presented. In particular, three analyses aiming at different ttH final states are reviewed. These include a search with the Higgs boson decaying to bb, a search in multileptonic final states and a search with H\\rightarrow~\\gamma\\gamma. The results from these analyses are combined, giving a ttH signal strength of $1.8\\pm0.8$ and excluding a ttH signal 3.2 larger than the SM expectation at 95\\% confidence level for a SM Higgs boson with a mass of 125.36 GeV.
Prospects for the search for Higgs bosons with vector boson fusion processes at the LHC
Rottlaender, Iris
2007-01-01
The search for the Higgs boson is one of the main physics goals of the Large Hadron Collider (LHC) and its two multi-purpose experiments, ATLAS and CMS. Vector boson fusion is the second largest production process for a standard model Higgs boson at the LHC and offers excellent means for background suppression. This paper gives an overview of the prospects of Higgs boson searches using vector boson fusion at the LHC. For a standard model Higgs boson, the decay channels H->tautau, H->WW and H-...
CERN Video Productions
2012-01-01
Peter Higgs answers questions about his feelings following the announcement of the discovery of a new particle by ATLAS and CMS that looks like the Higgs boson, at a seminar at CERN on July 4, 2012. He also explains his role in the proposal of a Higgs mechanism.
High-Temperature Atomic Superfluidity in Lattice Boson-Fermion Mixtures
Illuminati, F.; Albus, A
2003-01-01
We consider atomic Bose-Fermi mixtures in optical lattices and study the superfluidity of fermionic atoms due to s-wave pairing induced by boson-fermion interactions. We prove that the induced fermion-fermion coupling is always {\\it attractive} if the boson-boson on site interaction is repulsive, and predict the existence of an enhanced BEC--BCS crossover as the strength of the lattice potential is varied. We show that for direct on-site fermion-fermion {\\it repulsion}, the induced attraction...
Marzocchi,
2015-01-01
The discovery of the Higgs boson at the LHC completes the standard model (SM) of particle interactions. Albeit very successful, the SM does not provide answers to critical questions, such as the nature of dark matter or the hierarchy problem. For this reason, theories that predict the existence of new phenomena beyond the standard model (BSM theories) have been proposed. Many BSM theories predict the existence of new particles coupled to the Higgs boson. Therefore, the consistency of the SM a...
Introduction to bosonic string theory
International Nuclear Information System (INIS)
This is an introductory set of five lectures on bosonic string theory. The first one deals with the classical theory of bosonic strings. The second and third lectures cover quantization. Three basic quantization methods are sketched: the old covariant formalism, the light-cone gauge quantization, where the spectrum is derived and the Polyakov path integral formalism and in particular the partition function at one loop. Finally, the last lecture covers interactions, low energy effective action, the general idea of compactification and in particular toroidal compactification. The notes are based on books by Green, Schwarz and Witten, Polchinski, Lust and Theissen and Kaku and review papers by D'Hocker and Phong and O. Alvarez. (author)
A general approach to bosonization
Indian Academy of Sciences (India)
Girish S Setulur; V Meera
2007-10-01
We summarize recent developments in the ﬁeld of higher dimensional bosonization made by Setlur and collaborators and propose a general formula for the ﬁeld operator in terms of currents and densities in one dimension using a new ingredient known as a `singular complex number'. Using this formalism, we compute the Green function of the homogeneous electron gas in one spatial dimension with short-range interaction leading to the Luttinger liquid and also with long-range interactions that lead to a Wigner crystal whose momentum distribution computed recently exhibits essential singularities. We generalize the formalism to ﬁnite temperature by combining with the author's hydrodynamic approach. The one-particle Green function of this system with essential singularities cannot be easily computed using the traditional approach to bosonization which involves the introduction of momentum cutoffs, hence the more general approach of the present formalism is proposed as a suitable alternative.
Barbieri, Riccardo; Kannike, Kristjan; Sala, Filippo; Tesi, Andrea
2013-01-01
Now that one has been found, the search for signs of more scalars is a primary task of current and future experiments. In the motivated hypothesis that the extra Higgs bosons of the next-to-minimal supersymmetric Standard Model (NMSSM) be the lightest new particles around, we outline a possible overall strategy to search for signs of the CP-even states. This work complements Ref. arXiv:1304.3670.
Bosonic colored group field theory
Energy Technology Data Exchange (ETDEWEB)
Ben Geloun, Joseph [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France); University of Abomey-Calavi, Cotonou (BJ). International Chair in Mathematical Physics and Applications (ICMPA-UNESCO Chair); Universite Cheikh Anta Diop, Departement de Mathematiques et Informatique, Faculte des Sciences et Techniques, Dakar (Senegal); Magnen, Jacques [Ecole Polytechnique, Centre de Physique Theorique, Palaiseau Cedex (France); Rivasseau, Vincent [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France)
2010-12-15
Bosonic colored group field theory is considered. Focusing first on dimension four, namely the colored Ooguri group field model, the main properties of Feynman graphs are studied. This leads to a theorem on optimal perturbative bounds of Feynman amplitudes in the ''ultraspin'' (large spin) limit. The results are generalized in any dimension. Finally, integrating out two colors we write a new representation, which could be useful for the constructive analysis of this type of models. (orig.)
Electroweak boson production at LHCb
Directory of Open Access Journals (Sweden)
Wallace Ronan
2013-11-01
Full Text Available Measurements of W and Z boson production provide important tests of the Standard Model as well as being inputs for determining the parton density functions of the proton. W and Z production cross-sections, and their ratios, have been measured using the LHCb detector and are reported here. Datasets of up to 1 fb−1 at √s = 7 TeV are used.
Domains of bosonic functional integrals
International Nuclear Information System (INIS)
We propose a mathematical framework for bosonic Euclidean quantum field functional integrals based on the theory of integration on the dual algebraic vector space of classical field sources. We present a generalization of the Minlos-Dao Xing theorem and apply it to determine exactly the domain of integration associated to the functional integral representation of the two-dimensional quantum electrodynamics Schwinger generating functional. (author)
Collider Signatures of Goldstone Bosons
Cheung, Kingman; Yuan, Tzu-Chiang
2014-01-01
Recently Weinberg suggested that Goldstone bosons arising from the spontaneous breakdown of some global hidden symmetries can interact weakly in the early Universe and account for a fraction of the effective number of neutrino species N_{eff}, which has been reported persistently 2\\sigma away from its expected value of three. In this work, we study in some details a number of experimental constraints on this interesting idea based on the simplest possibility of a global U(1), as studied by Weinberg. We work out the decay branching ratios of the associated light scalar field \\sigma and suggest a possible collider signature at the Large Hadron Collider (LHC). In some corners of the parameter space, the scalar field \\sigma can decay into a pair of pions with a branching ratio of order 10% while the rest is mostly a pair of Goldstone bosons. The collider signature would be gluon fusion into the standard model Higgs boson gg -> H followed by H -> \\sigma \\sigma -> (\\pi\\pi) (\\alpha\\alpha) where \\alpha is the Goldsto...
Distinguishing a SM-like MSSM Higgs boson from SM Higgs boson at muon collider
Indian Academy of Sciences (India)
Jai Kumar Singhal; Sardar Singh; Ashok K Nagawat
2007-06-01
We explore the possibility of distinguishing the SM-like MSSM Higgs boson from the SM Higgs boson via Higgs boson pair production at future muon collider. We study the behavior of the production cross-section in SM and MSSM with Higgs boson mass for various MSSM parameters tan and A. We observe that at fixed CM energy, in the SM, the total cross-section increases with the increase in Higgs boson mass whereas this trend is reversed for the MSSM. The changes that occur for the MSSM in comparison to the SM predictions are quantified in terms of the relative percentage deviation in cross-section. The observed deviations in cross-section for different choices of Higgs boson masses suggest that the measurements of the cross-section could possibly distinguish the SM-like MSSM Higgs boson from the SM Higgs boson.
An Introduction to Boson-Sampling
Gard, Bryan T.; Motes, Keith R.; Olson, Jonathan P.; Rohde, Peter P.; Dowling, Jonathan P.
2015-06-01
Boson-sampling is a simplified model for quantum computing that may hold the key to implementing the first ever post-classical quantum computer. Boson-sampling is a non-universal quantum computer that is significantly more straightforward to build than any universal quantum computer proposed so far. We begin this chapter by motivating boson-sampling and discussing the history of linear optics quantum computing. We then summarize the boson-sampling formalism, discuss what a sampling problem is, explain why boson-sampling is easier than linear optics quantum computing, and discuss the Extended Church-Turing thesis. Next, sampling with other classes of quantum optical states is analyzed. Finally, we discuss the feasibility of building a boson-sampling device using existing technology.
Dutta, Bhaskar; Gao, Yu; Ghosh, Tathagata; Kamon, Teruki
2014-01-01
This paper studies the pair production of the doubly charged Higgs boson of the left-right symmetric models using multilepton final state in the vector boson fusion (VBF)-like processes. The study is performed in the framework consistent with the model's correction to the standard model $\\rho_{EW}$ parameter. VBF topological cuts, number of leptons in the final state and $p_T$ cuts on the leptons are found to be effective in suppressing the background. Significant mass reach can be achieved for exclusion/discovery of the doubly charge Higgs boson for the upcoming LHC run with a luminosity of $\\mathcal{O}(10^3)$ fb$^{-1}$.
New Results on Charged Compact Boson Stars
Kumar, Sanjeev; Kulshreshtha, Daya Shankar
2016-01-01
In this work we present some new results which we have obtained in a study of the phase diagram of charged compact boson stars in the theory involving massive complex scalar fields coupled to the U(1) gauge field and gravity in a conical potential in the presence of a cosmological constant $\\Lambda$ which we treat as a free parameter taking positive and negative values and thereby allowing us to study the theory in the de Sitter and Anti de Sitter spaces respectively. In our studies, we obtain four bifurcation points (possibility of more bifurcation points being not ruled out) in the de Sitter region. We present a detailed discussion of the various regions in our phase diagram with respect to four bifurcation points. Our theory is seen to have rich physics in a particular domain for positive values of $\\Lambda$ which is consistent with the accelerated expansion of the universe.
New results on charged compact boson stars
Kumar, Sanjeev; Kulshreshtha, Usha; Kulshreshtha, Daya Shankar
2016-05-01
In this work we present some new results that we have obtained in a study of the phase diagram of charged compact boson stars in the theory involving massive complex scalar fields coupled to the U(1) gauge field and gravity in a conical potential in the presence of a cosmological constant Λ , which we treat as a free parameter taking positive and negative values and thereby allowing us to study the theory in de Sitter and anti de Sitter spaces, respectively. We obtain four bifurcation points (the possibility of more bifurcation points not being ruled out) in the de Sitter region. We present a detailed discussion of the various regions in our phase diagram with respect to four bifurcation points. Our theory is seen to have rich physics in a particular domain for positive values of Λ , which is consistent with the accelerated expansion of the Universe.
Black holes as bosonic Gaussian channels
Bradler, Kamil
2014-01-01
We identify the quantum channels corresponding to the interaction of a Gaussian quantum state with an already formed Schwarzschild black hole. Using recent advances in the classification of one-mode bosonic Gaussian channels we find that (with one exception) the black hole Gaussian channels lie in the non-entanglement breaking subset of the lossy channels $\\mathcal{C}({\\rm loss})$, amplifying channels $\\mathcal{C}({\\rm amp})$ and classical-noise channels $\\mathcal{B}_2$. We show that the channel parameters depend on the black hole mass and the properties of the potential barrier surrounding it. This classification enables us to calculate the classical and quantum capacity of the black hole and to estimate the quantum capacity where no tractable quantum capacity expression exists today. We discuss these findings in the light of the black hole quantum information loss problem.
On the origins and the historical roots of the Higgs boson research from a bibliometric perspective
Barth, A.; Marx, W.; Bornmann, L.; Mutz, R.
2014-06-01
The subject of our present paper is the analysis of the origins or historical roots of the Higgs boson research from a bibliometric perspective, using a segmented regression analysis in combination with a method named reference publication year spectroscopy (RPYS). Our analysis is based on the references cited in the Higgs boson publications published since 1974. The objective of our analysis consists of identifying specific individual publications in the Higgs boson research context to which the scientific community frequently had referred to. We are interested in seminal works which contributed to a high extent to the discovery of the Higgs boson. Our results show that researchers in the Higgs boson field preferably refer to more recently published papers —particularly papers published since the beginning of the sixties. For example, our analysis reveals seven major contributions which appeared within the sixties: Englert and Brout (1964), Higgs (1964, 2 papers), and Guralnik et al. (1964) on the Higgs mechanism as well as Glashow (1961), Weinberg (1967), and Salam (1968) on the unification of weak and electromagnetic interaction. Even if the Nobel Prize award highlights the outstanding importance of the work of Peter Higgs and Francois Englert, bibliometrics offer the additional possibility of getting hints to other publications in this research field (especially to historical publications), which are of vital importance from the expert point of view.
Evidence for the direct decay of the 125 GeV Higgs boson to fermions
Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hartl, Christian; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Treberer-Treberspurg, Wolfgang; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Alderweireldt, Sara; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Knutsson, Albert; Luyckx, Sten; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Heracleous, Natalie; Kalogeropoulos, Alexis; Keaveney, James; Kim, Tae Jeong; Lowette, Steven; Maes, Michael; Olbrechts, Annik; Python, Quentin; Strom, Derek; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Caillol, Cécile; Clerbaux, Barbara; De Lentdecker, Gilles; Favart, Laurent; Gay, Arnaud; Léonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Perniè, Luca; Reis, Thomas; Seva, Tomislav; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Benucci, Leonardo; Cimmino, Anna; Costantini, Silvia; Crucy, Shannon; Dildick, Sven; Garcia, Guillaume; Klein, Benjamin; Lellouch, Jérémie; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Salva Diblen, Sinem; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Beluffi, Camille; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Da Silveira, Gustavo Gil; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Jez, Pavel; Komm, Matthias; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Popov, Andrey; Quertenmont, Loic; Selvaggi, Michele; Vidal Marono, Miguel; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; Dos Reis Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Chinellato, Jose; Custódio, Analu; Da Costa, Eliza Melo; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Malek, Magdalena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santaolalla, Javier; Santoro, Alberto; Sznajder, Andre; Tonelli Manganote, Edmilson José; Vilela Pereira, Antonio; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Marinov, Andrey; Piperov, Stefan; Rodozov, Mircho; Sultanov, Georgi; Vutova, Mariana; Dimitrov, Anton; Glushkov, Ivan; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Chen, Mingshui; Du, Ran; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Plestina, Roko; Tao, Junquan; Wang, Xianyou; Wang, Zheng; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Qiang; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Chaparro Sierra, Luisa Fernanda; Florez, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Morovic, Srecko; Sudic, Lucija; Attikis, Alexandros; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Bodlak, Martin; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Mahmoud, Mohammed; Mahrous, Ayman; Radi, Amr; Kadastik, Mario; Müntel, Mait; Murumaa, Marion; Raidal, Martti; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Wendland, Lauri; Tuuva, Tuure; Besancon, Marc; Couderc, Fabrice; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Favaro, Carlotta; Ferri, Federico; Ganjour, Serguei; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Nayak, Aruna; Rander, John; Rosowsky, André; Titov, Maksym; Baffioni, Stephanie; Beaudette, Florian; Busson, Philippe; Charlot, Claude; Daci, Nadir; Dahms, Torsten; Dalchenko, Mykhailo; Dobrzynski, Ludwik; Filipovic, Nicolas; Florent, Alice; Granier de Cassagnac, Raphael; Mastrolorenzo, Luca; Miné, Philippe; Mironov, Camelia; Naranjo, Ivo Nicolas; Nguyen, Matthew; Ochando, Christophe; Paganini, Pascal; Sabes, David; Salerno, Roberto; Sauvan, Jean-baptiste; Sirois, Yves; Veelken, Christian; Yilmaz, Yetkin; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Bloch, Daniel; Brom, Jean-Marie; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Drouhin, Frédéric; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Goetzmann, Christophe; Juillot, Pierre; Le Bihan, Anne-Catherine; Van Hove, Pierre; Gadrat, Sébastien; Beauceron, Stephanie; Beaupere, Nicolas; Boudoul, Gaelle; Brochet, Sébastien; Carrillo Montoya, Camilo Andres; Chasserat, Julien; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Fan, Jiawei; Fay, Jean; Gascon, Susan; Gouzevitch, Maxime; Ille, Bernard; Kurca, Tibor; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Ruiz Alvarez, José David; Sgandurra, Louis; Sordini, Viola; Vander Donckt, Muriel; Verdier, Patrice; Viret, Sébastien; Xiao, Hong; Tsamalaidze, Zviad; Autermann, Christian; Beranek, Sarah; Bontenackels, Michael; Calpas, Betty; Edelhoff, Matthias; Feld, Lutz; Hindrichs, Otto; Klein, Katja; Ostapchuk, Andrey; Perieanu, Adrian; Raupach, Frank; Sammet, Jan; Schael, Stefan; Sprenger, Daniel; Weber, Hendrik; Wittmer, Bruno; Zhukov, Valery; Ata, Metin; Caudron, Julien; Dietz-Laursonn, Erik; Duchardt, Deborah; Erdmann, Martin; Fischer, Robert; Güth, Andreas; Hebbeker, Thomas; Heidemann, Carsten; Hoepfner, Kerstin; Klingebiel, Dennis; Knutzen, Simon; Kreuzer, Peter; Merschmeyer, Markus; Meyer, Arnd; Olschewski, Mark; Padeken, Klaas; Papacz, Paul; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Teyssier, Daniel; Thüer, Sebastian; Weber, Martin; Cherepanov, Vladimir; Erdogan, Yusuf; Flügge, Günter; Geenen, Heiko; Geisler, Matthias; Haj Ahmad, Wael; Hoehle, Felix; Kargoll, Bastian; Kress, Thomas; Kuessel, Yvonne; Lingemann, Joschka; Nowack, Andreas; Nugent, Ian Michael; Perchalla, Lars; Pooth, Oliver; Stahl, Achim; Asin, Ivan; Bartosik, Nazar; Behr, Joerg; Behrenhoff, Wolf; Behrens, Ulf; Bell, Alan James; Bergholz, Matthias; Bethani, Agni; Borras, Kerstin; Burgmeier, Armin; Cakir, Altan; Calligaris, Luigi; Campbell, Alan; Choudhury, Somnath; Costanza, Francesco; Diez Pardos, Carmen; Dooling, Samantha; Dorland, Tyler; Eckerlin, Guenter; Eckstein, Doris; Eichhorn, Thomas; Flucke, Gero; Geiser, Achim; Grebenyuk, Anastasia; Gunnellini, Paolo; Habib, Shiraz; Hauk, Johannes; Hellwig, Gregor; Hempel, Maria; Horton, Dean; Jung, Hannes; Kasemann, Matthias; Katsas, Panagiotis; Kieseler, Jan; Kleinwort, Claus; Krämer, Mira; Krücker, Dirk; Lange, Wolfgang; Leonard, Jessica; Lipka, Katerina; Lohmann, Wolfgang; Lutz, Benjamin; Mankel, Rainer; Marfin, Ihar; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mnich, Joachim; Mussgiller, Andreas; Naumann-Emme, Sebastian; Novgorodova, Olga; Nowak, Friederike; Ntomari, Eleni; Perrey, Hanno; Petrukhin, Alexey; Pitzl, Daniel; Placakyte, Ringaile; Raspereza, Alexei; Ribeiro Cipriano, Pedro M; Riedl, Caroline; Ron, Elias; Sahin, Mehmet Özgür; Salfeld-Nebgen, Jakob; Saxena, Pooja; Schmidt, Ringo; Schoerner-Sadenius, Thomas; Schröder, Matthias; Stein, Matthias; Vargas Trevino, Andrea Del Rocio; Walsh, Roberval; Wissing, Christoph; Aldaya Martin, Maria; Blobel, Volker; Centis Vignali, Matteo; Enderle, Holger; Erfle, Joachim; Garutti, Erika; Goebel, Kristin; Görner, Martin; Gosselink, Martijn; Haller, Johannes; Höing, Rebekka Sophie; Kirschenmann, Henning; Klanner, Robert; Kogler, Roman; Lange, Jörn; Lapsien, Tobias; Lenz, Teresa; Marchesini, Ivan; Ott, Jochen; Peiffer, Thomas; Pietsch, Niklas; Rathjens, Denis; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schlieckau, Eike; Schmidt, Alexander; Seidel, Markus; Sibille, Jennifer; Sola, Valentina; Stadie, Hartmut; Steinbrück, Georg; Troendle, Daniel; Usai, Emanuele; Vanelderen, Lukas; Barth, Christian; Baus, Colin; Berger, Joram; Böser, Christian; Butz, Erik; Chwalek, Thorsten; De Boer, Wim; Descroix, Alexis; Dierlamm, Alexander; Feindt, Michael; Guthoff, Moritz; Hartmann, Frank; Hauth, Thomas; Held, Hauke; Hoffmann, Karl-Heinz; Husemann, Ulrich; Katkov, Igor; Kornmayer, Andreas; Kuznetsova, Ekaterina; Lobelle Pardo, Patricia; Martschei, Daniel; Mozer, Matthias Ulrich; Müller, Thomas; Niegel, Martin; Nürnberg, Andreas; Oberst, Oliver; Quast, Gunter; Rabbertz, Klaus; Ratnikov, Fedor; Röcker, Steffen; Schilling, Frank-Peter; Schott, Gregory; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Ulrich, Ralf; Wagner-Kuhr, Jeannine; Wayand, Stefan; Weiler, Thomas; Wolf, Roger; Zeise, Manuel; Anagnostou, Georgios; Daskalakis, Georgios; Geralis, Theodoros; Giakoumopoulou, Viktoria Athina; Kesisoglou, Stilianos; Kyriakis, Aristotelis; Loukas, Demetrios; Markou, Athanasios; Markou, Christos; Psallidas, Andreas; Topsis-Giotis, Iasonas; Gouskos, Loukas; Panagiotou, Apostolos; Saoulidou, Niki; Stiliaris, Efstathios; Aslanoglou, Xenofon; Evangelou, Ioannis; Flouris, Giannis; Foudas, Costas; Jones, John; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Paradas, Evangelos; Bencze, Gyorgy; Hajdu, Csaba; Hidas, Pàl; Horvath, Dezso; Sikler, Ferenc; Veszpremi, Viktor; Vesztergombi, Gyorgy; Zsigmond, Anna Julia; Beni, Noemi; Czellar, Sandor; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Karancsi, János; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Swain, Sanjay Kumar; Beri, Suman Bala; Bhatnagar, Vipin; Dhingra, Nitish; Gupta, Ruchi; Kaur, Manjit; Mittal, Monika; Nishu, Nishu; Sharma, Archana; Singh, Jasbir; Kumar, Ashok; Kumar, Arun; Ahuja, Sudha; Bhardwaj, Ashutosh; Choudhary, Brajesh C; Kumar, Ajay; Malhotra, Shivali; Naimuddin, Md; Ranjan, Kirti; Sharma, Varun; Shivpuri, Ram Krishen; Banerjee, Sunanda; Bhattacharya, Satyaki; Chatterjee, Kalyanmoy; Dutta, Suchandra; Gomber, Bhawna; Jain, Sandhya; Jain, Shilpi; Khurana, Raman; Modak, Atanu; Mukherjee, Swagata; Roy, Debarati; Sarkar, Subir; Sharan, Manoj; Singh, Anil; Abdulsalam, Abdulla; Dutta, Dipanwita; Kailas, Swaminathan; Kumar, Vineet; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Topkar, Anita; Aziz, Tariq; Chatterjee, Rajdeep Mohan; Ganguly, Sanmay; Ghosh, Saranya; Guchait, Monoranjan; Gurtu, Atul; Kole, Gouranga; Kumar, Sanjeev; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Parida, Bibhuti; Sudhakar, Katta; Wickramage, Nadeesha; Banerjee, Sudeshna; Dewanjee, Ram Krishna; Dugad, Shashikant; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Behnamian, Hadi; Etesami, Seyed Mohsen; Fahim, Ali; Jafari, Abideh; Khakzad, Mohsen; Mohammadi Najafabadi, Mojtaba; Naseri, Mohsen; Paktinat Mehdiabadi, Saeid; Safarzadeh, Batool; Zeinali, Maryam; Grunewald, Martin; Abbrescia, Marcello; Barbone, Lucia; Calabria, Cesare; Chhibra, Simranjit Singh; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Fiore, Luigi; Iaselli, Giuseppe; Maggi, Giorgio; Maggi, Marcello; My, Salvatore; Nuzzo, Salvatore; Pacifico, Nicola; Pompili, Alexis; Pugliese, Gabriella; Radogna, Raffaella; Selvaggi, Giovanna; Silvestris, Lucia; Singh, Gurpreet; Venditti, Rosamaria; Verwilligen, Piet; Zito, Giuseppe; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Brigliadori, Luca; Campanini, Renato; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Codispoti, Giuseppe; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Grandi, Claudio; Guiducci, Luigi; Marcellini, Stefano; Masetti, Gianni; Meneghelli, Marco; Montanari, Alessandro; Navarria, Francesco; Odorici, Fabrizio; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gian Piero; Tosi, Nicolò; Travaglini, Riccardo; Albergo, Sebastiano; Cappello, Gigi; Chiorboli, Massimiliano; Costa, Salvatore; Giordano, Ferdinando; Potenza, Renato; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Gallo, Elisabetta; Gonzi, Sandro; Gori, Valentina; Lenzi, Piergiulio; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Fabbri, Franco; Piccolo, Davide; Fabbricatore, Pasquale; Ferro, Fabrizio; Lo Vetere, Maurizio; Musenich, Riccardo; Robutti, Enrico; Tosi, Silvano; Dinardo, Mauro Emanuele; Fiorendi, Sara; Gennai, Simone; Gerosa, Raffaele; Ghezzi, Alessio; Govoni, Pietro; Lucchini, Marco Toliman; Malvezzi, Sandra; Manzoni, Riccardo Andrea; Martelli, Arabella; Marzocchi, Badder; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Tabarelli de Fatis, Tommaso; Buontempo, Salvatore; Cavallo, Nicola; Di Guida, Salvatore; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Meola, Sabino; Merola, Mario; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bisello, Dario; Branca, Antonio; Carlin, Roberto; Checchia, Paolo; Dorigo, Tommaso; Galanti, Mario; Gasparini, Fabrizio; Gasparini, Ugo; Giubilato, Piero; Gonella, Franco; Gozzelino, Andrea; Kanishchev, Konstantin; Lacaprara, Stefano; Lazzizzera, Ignazio; Margoni, Martino; Meneguzzo, Anna Teresa; Montecassiano, Fabio; Pazzini, Jacopo; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Vanini, Sara; Zotto, Pierluigi; Zucchetta, Alberto; Zumerle, Gianni; Gabusi, Michele; Ratti, Sergio P; Riccardi, Cristina; Salvini, Paola; Vitulo, Paolo; Biasini, Maurizio; Bilei, Gian Mario; Fanò, Livio; Lariccia, Paolo; Mantovani, Giancarlo; Menichelli, Mauro; Romeo, Francesco; Saha, Anirban; Santocchia, Attilio; Spiezia, Aniello; Androsov, Konstantin; Azzurri, Paolo; Bagliesi, Giuseppe; Bernardini, Jacopo; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; Ciocci, Maria Agnese; Dell'Orso, Roberto; Donato, Silvio; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Grippo, Maria Teresa; Kraan, Aafke; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Moon, Chang-Seong; Palla, Fabrizio; Rizzi, Andrea; Savoy-Navarro, Aurore; Serban, Alin Titus; Spagnolo, Paolo; Squillacioti, Paola; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Vernieri, Caterina; Barone, Luciano; Cavallari, Francesca; Del Re, Daniele; Diemoz, Marcella; Grassi, Marco; Jorda, Clara; Longo, Egidio; Margaroli, Fabrizio; Meridiani, Paolo; Micheli, Francesco; Nourbakhsh, Shervin; Organtini, Giovanni; Paramatti, Riccardo; Rahatlou, Shahram; Rovelli, Chiara; Soffi, Livia; Traczyk, Piotr; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Bellan, Riccardo; Biino, Cristina; Cartiglia, Nicolo; Casasso, Stefano; Costa, Marco; Degano, Alessandro; Demaria, Natale; Finco, Linda; Mariotti, Chiara; Maselli, Silvia; Migliore, Ernesto; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Ortona, Giacomo; Pacher, Luca; Pastrone, Nadia; Pelliccioni, Mario; Pinna Angioni, Gian Luca; Potenza, Alberto; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Solano, Ada; Staiano, Amedeo; Tamponi, Umberto; Belforte, Stefano; Candelise, Vieri; Casarsa, Massimo; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; La Licata, Chiara; Marone, Matteo; Montanino, Damiana; Schizzi, Andrea; Umer, Tomo; Zanetti, Anna; Chang, Sunghyun; Kim, Tae Yeon; Nam, Soon-Kwon; Kim, Dong Hee; Kim, Gui Nyun; Kim, Ji Eun; Kim, Min Suk; Kong, Dae Jung; Lee, Sangeun; Oh, Young Do; Park, Hyangkyu; Sakharov, Alexandre; Son, Dong-Chul; Kim, Jae Yool; Kim, Zero Jaeho; Song, Sanghyeon; Choi, Suyong; Gyun, Dooyeon; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Yongsun; Lee, Byounghoon; Lee, Kyong Sei; Park, Sung Keun; Roh, Youn; Choi, Minkyoo; Kim, Ji Hyun; Park, Chawon; Park, Inkyu; Park, Sangnam; Ryu, Geonmo; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Kwon, Eunhyang; Lee, Jongseok; Seo, Hyunkwan; Yu, Intae; Juodagalvis, Andrius; Komaragiri, Jyothsna Rani; Castilla-Valdez, Heriberto; De La Cruz-Burelo, Eduard; Heredia-de La Cruz, Ivan; Lopez-Fernandez, Ricardo; Martínez-Ortega, Jorge; Sánchez Hernández, Alberto; Villasenor-Cendejas, Luis Manuel; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Salazar Ibarguen, Humberto Antonio; Casimiro Linares, Edgar; Morelos Pineda, Antonio; Krofcheck, David; Butler, Philip H; Doesburg, Robert; Reucroft, Steve; Ahmad, Ashfaq; Ahmad, Muhammad; Asghar, Muhammad Irfan; Butt, Jamila; Hassan, Qamar; Hoorani, Hafeez R; Khan, Wajid Ali; Khurshid, Taimoor; Qazi, Shamona; Shah, Mehar Ali; Shoaib, Muhammad; Bialkowska, Helena; Bluj, Michal; Boimska, Bożena; Frueboes, Tomasz; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Wrochna, Grzegorz; Zalewski, Piotr; Brona, Grzegorz; Bunkowski, Karol; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Misiura, Maciej; Wolszczak, Weronika; Bargassa, Pedrame; Beirão Da Cruz E Silva, Cristóvão; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Nguyen, Federico; Rodrigues Antunes, Joao; Seixas, Joao; Varela, Joao; Vischia, Pietro; Golutvin, Igor; Gorbunov, Ilya; Karjavin, Vladimir; Konoplyanikov, Viktor; Korenkov, Vladimir; Kozlov, Guennady; Lanev, Alexander; Malakhov, Alexander; Matveev, Viktor; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Savina, Maria; Shmatov, Sergey; Shulha, Siarhei; Skatchkov, Nikolai; Smirnov, Vitaly; Zarubin, Anatoli; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Vorobyev, Andrey; Andreev, Yuri; Dermenev, Alexander; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Pashenkov, Anatoli; Tlisov, Danila; Toropin, Alexander; Epshteyn, Vladimir; Gavrilov, Vladimir; Lychkovskaya, Natalia; Popov, Vladimir; Safronov, Grigory; Semenov, Sergey; Spiridonov, Alexander; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Leonidov, Andrey; Mesyats, Gennady; Rusakov, Sergey V; Vinogradov, Alexey; Belyaev, Andrey; Boos, Edouard; Dubinin, Mikhail; Dudko, Lev; Ershov, Alexander; Gribushin, Andrey; Klyukhin, Vyacheslav; Kodolova, Olga; Lokhtin, Igor; Obraztsov, Stepan; Perfilov, Maxim; Petrushanko, Sergey; Savrin, Viktor; Azhgirey, Igor; Bayshev, Igor; Bitioukov, Sergei; Kachanov, Vassili; Kalinin, Alexey; Konstantinov, Dmitri; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Djordjevic, Milos; Ekmedzic, Marko; Milosevic, Jovan; Aguilar-Benitez, Manuel; Alcaraz Maestre, Juan; Battilana, Carlo; Calvo, Enrique; Cerrada, Marcos; Chamizo Llatas, Maria; Colino, Nicanor; De La Cruz, Begona; Delgado Peris, Antonio; Domínguez Vázquez, Daniel; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Ferrando, Antonio; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M; Josa, Maria Isabel; Merino, Gonzalo; Navarro De Martino, Eduardo; Pérez Calero Yzquierdo, Antonio María; Puerta Pelayo, Jesus; Quintario Olmeda, Adrián; Redondo, Ignacio; Romero, Luciano; Soares, Mara Senghi; Willmott, Carlos; Albajar, Carmen; de Trocóniz, Jorge F; Missiroli, Marino; Brun, Hugues; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Lloret Iglesias, Lara; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Duarte Campderros, Jordi; Fernandez, Marcos; Gomez, Gervasio; Gonzalez Sanchez, Javier; Graziano, Alberto; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Piedra Gomez, Jonatan; Rodrigo, Teresa; Rodríguez-Marrero, Ana Yaiza; Ruiz-Jimeno, Alberto; Scodellaro, Luca; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Bachtis, Michail; Baillon, Paul; Ball, Austin; Barney, David; Benaglia, Andrea; Bendavid, Joshua; Benhabib, Lamia; Benitez, Jose F; Bernet, Colin; Bianchi, Giovanni; Bloch, Philippe; Bocci, Andrea; Bonato, Alessio; Bondu, Olivier; Botta, Cristina; Breuker, Horst; Camporesi, Tiziano; Cerminara, Gianluca; Christiansen, Tim; Coarasa Perez, Jose Antonio; Colafranceschi, Stefano; D'Alfonso, Mariarosaria; D'Enterria, David; Dabrowski, Anne; David Tinoco Mendes, Andre; De Guio, Federico; De Roeck, Albert; De Visscher, Simon; Dobson, Marc; Dupont-Sagorin, Niels; Elliott-Peisert, Anna; Eugster, Jürg; Franzoni, Giovanni; Funk, Wolfgang; Giffels, Manuel; Gigi, Dominique; Gill, Karl; Girone, Maria; Giunta, Marina; Glege, Frank; Gomez-Reino Garrido, Robert; Gowdy, Stephen; Guida, Roberto; Hammer, Josef; Hansen, Magnus; Harris, Philip; Hegeman, Jeroen; Innocente, Vincenzo; Janot, Patrick; Karavakis, Edward; Kousouris, Konstantinos; Krajczar, Krisztian; Lecoq, Paul; Lourenco, Carlos; Magini, Nicolo; Malgeri, Luca; Mannelli, Marcello; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moortgat, Filip; Mulders, Martijn; Musella, Pasquale; Orsini, Luciano; Palencia Cortezon, Enrique; Pape, Luc; Perez, Emmanuelle; Perrozzi, Luca; Petrilli, Achille; Petrucciani, Giovanni; Pfeiffer, Andreas; Pierini, Maurizio; Pimiä, Martti; Piparo, Danilo; Plagge, Michael; Racz, Attila; Reece, William; Rolandi, Gigi; Rovere, Marco; Sakulin, Hannes; Santanastasio, Francesco; Schäfer, Christoph; Schwick, Christoph; Sekmen, Sezen; Sharma, Archana; Siegrist, Patrice; Silva, Pedro; Simon, Michal; Sphicas, Paraskevas; Steggemann, Jan; Stieger, Benjamin; Stoye, Markus; Treille, Daniel; Tsirou, Andromachi; Veres, Gabor Istvan; Vlimant, Jean-Roch; Wöhri, Hermine Katharina; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; König, Stefan; Kotlinski, Danek; Langenegger, Urs; Renker, Dieter; Rohe, Tilman; Bachmair, Felix; Bäni, Lukas; Bianchini, Lorenzo; Bortignon, Pierluigi; Buchmann, Marco-Andrea; Casal, Bruno; Chanon, Nicolas; Deisher, Amanda; Dissertori, Günther; Dittmar, Michael; Donegà, Mauro; Dünser, Marc; Eller, Philipp; Grab, Christoph; Hits, Dmitry; Lustermann, Werner; Mangano, Boris; Marini, Andrea Carlo; Martinez Ruiz del Arbol, Pablo; Meister, Daniel; Mohr, Niklas; Nägeli, Christoph; Nef, Pascal; Nessi-Tedaldi, Francesca; Pandolfi, Francesco; Pauss, Felicitas; Peruzzi, Marco; Quittnat, Milena; Rebane, Liis; Ronga, Frederic Jean; Rossini, Marco; Starodumov, Andrei; Takahashi, Maiko; Theofilatos, Konstantinos; Wallny, Rainer; Weber, Hannsjoerg Artur; Amsler, Claude; Canelli, Maria Florencia; Chiochia, Vincenzo; De Cosa, Annapaola; Hinzmann, Andreas; Hreus, Tomas; Ivova Rikova, Mirena; Kilminster, Benjamin; Millan Mejias, Barbara; Ngadiuba, Jennifer; Robmann, Peter; Snoek, Hella; Taroni, Silvia; Verzetti, Mauro; Yang, Yong; Cardaci, Marco; Chen, Kuan-Hsin; Ferro, Cristina; Kuo, Chia-Ming; Li, Syue-Wei; Lin, Willis; Lu, Yun-Ju; Volpe, Roberta; Yu, Shin-Shan; Bartalini, Paolo; Chang, Paoti; Chang, You-Hao; Chang, Yu-Wei; Chao, Yuan; Chen, Kai-Feng; Chen, Po-Hsun; Dietz, Charles; Grundler, Ulysses; Hou, George Wei-Shu; Hsiung, Yee; Kao, Kai-Yi; Lei, Yeong-Jyi; Liu, Yueh-Feng; Lu, Rong-Shyang; Majumder, Devdatta; Petrakou, Eleni; Shi, Xin; Shiu, Jing-Ge; Tzeng, Yeng-Ming; Wang, Minzu; Wilken, Rachel; Asavapibhop, Burin; Suwonjandee, Narumon; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dozen, Candan; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gokbulut, Gul; Gurpinar, Emine; Hos, Ilknur; Kangal, Evrim Ersin; Kayis Topaksu, Aysel; Onengut, Gulsen; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, Ayse; Sogut, Kenan; Sunar Cerci, Deniz; Tali, Bayram; Topakli, Huseyin; Vergili, Mehmet; Akin, Ilina Vasileva; Aliev, Takhmasib; Bilin, Bugra; Bilmis, Selcuk; Deniz, Muhammed; Gamsizkan, Halil; Guler, Ali Murat; Karapinar, Guler; Ocalan, Kadir; Ozpineci, Altug; Serin, Meltem; Sever, Ramazan; Surat, Ugur Emrah; Yalvac, Metin; Zeyrek, Mehmet; Gülmez, Erhan; Isildak, Bora; Kaya, Mithat; Kaya, Ozlem; Ozkorucuklu, Suat; Bahtiyar, Hüseyin; Barlas, Esra; Cankocak, Kerem; Günaydin, Yusuf Oguzhan; Vardarli, Fuat Ilkehan; Yücel, Mete; Levchuk, Leonid; Sorokin, Pavel; Brooke, James John; Clement, Emyr; Cussans, David; Flacher, Henning; Frazier, Robert; Goldstein, Joel; Grimes, Mark; Heath, Greg P; Heath, Helen F; Jacob, Jeson; Kreczko, Lukasz; Lucas, Chris; Meng, Zhaoxia; Newbold, Dave M; Paramesvaran, Sudarshan; Poll, Anthony; Senkin, Sergey; Smith, Vincent J; Williams, Thomas; Bell, Ken W; Belyaev, Alexander; Brew, Christopher; Brown, Robert M; Cockerill, David JA; Coughlan, John A; Harder, Kristian; Harper, Sam; Ilic, Jelena; Olaiya, Emmanuel; Petyt, David; Shepherd-Themistocleous, Claire; Thea, Alessandro; Tomalin, Ian R; Womersley, William John; Worm, Steven; Baber, Mark; Bainbridge, Robert; Buchmuller, Oliver; Burton, Darren; Colling, David; Cripps, Nicholas; Cutajar, Michael; Dauncey, Paul; Davies, Gavin; Della Negra, Michel; Ferguson, William; Fulcher, Jonathan; Futyan, David; Gilbert, Andrew; Guneratne Bryer, Arlo; Hall, Geoffrey; Hatherell, Zoe; Hays, Jonathan; Iles, Gregory; Jarvis, Martyn; Karapostoli, Georgia; Kenzie, Matthew; Lane, Rebecca; Lucas, Robyn; Lyons, Louis; Magnan, Anne-Marie; Marrouche, Jad; Mathias, Bryn; Nandi, Robin; Nash, Jordan; Nikitenko, Alexander; Pela, Joao; Pesaresi, Mark; Petridis, Konstantinos; Pioppi, Michele; Raymond, David Mark; Rogerson, Samuel; Rose, Andrew; Seez, Christopher; Sharp, Peter; Sparrow, Alex; Tapper, Alexander; Vazquez Acosta, Monica; Virdee, Tejinder; Wakefield, Stuart; Wardle, Nicholas; Cole, Joanne; Hobson, Peter R; Khan, Akram; Kyberd, Paul; Leggat, Duncan; Leslie, Dawn; Martin, William; Reid, Ivan; Symonds, Philip; Teodorescu, Liliana; Turner, Mark; Dittmann, Jay; Hatakeyama, Kenichi; Kasmi, Azeddine; Liu, Hongxuan; Scarborough, Tara; Charaf, Otman; Cooper, Seth; Henderson, Conor; Rumerio, Paolo; Avetisyan, Aram; Bose, Tulika; Fantasia, Cory; Heister, Arno; Lawson, Philip; Lazic, Dragoslav; Richardson, Clint; Rohlf, James; Sperka, David; St John, Jason; Sulak, Lawrence; Alimena, Juliette; Bhattacharya, Saptaparna; Christopher, Grant; Cutts, David; Demiragli, Zeynep; Ferapontov, Alexey; Garabedian, Alex; Heintz, Ulrich; Jabeen, Shabnam; Kukartsev, Gennadiy; Laird, Edward; Landsberg, Greg; Luk, Michael; Narain, Meenakshi; Segala, Michael; Sinthuprasith, Tutanon; Speer, Thomas; Swanson, Joshua; Breedon, Richard; Breto, Guillermo; Calderon De La Barca Sanchez, Manuel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Conway, Rylan; Cox, Peter Timothy; Erbacher, Robin; Gardner, Michael; Ko, Winston; Kopecky, Alexandra; Lander, Richard; Miceli, Tia; Mulhearn, Michael; Pellett, Dave; Pilot, Justin; Ricci-Tam, Francesca; Rutherford, Britney; Searle, Matthew; Shalhout, Shalhout; Smith, John; Squires, Michael; Tripathi, Mani; Wilbur, Scott; Yohay, Rachel; Andreev, Valeri; Cline, David; Cousins, Robert; Erhan, Samim; Everaerts, Pieter; Farrell, Chris; Felcini, Marta; Hauser, Jay; Ignatenko, Mikhail; Jarvis, Chad; Rakness, Gregory; Takasugi, Eric; Valuev, Vyacheslav; Weber, Matthias; Babb, John; Clare, Robert; Ellison, John Anthony; Gary, J William; Hanson, Gail; Heilman, Jesse; Jandir, Pawandeep; Lacroix, Florent; Liu, Hongliang; Long, Owen Rosser; Luthra, Arun; Malberti, Martina; Nguyen, Harold; Shrinivas, Amithabh; Sturdy, Jared; Sumowidagdo, Suharyo; Wimpenny, Stephen; Andrews, Warren; Branson, James G; Cerati, Giuseppe Benedetto; Cittolin, Sergio; D'Agnolo, Raffaele Tito; Evans, David; Holzner, André; Kelley, Ryan; Kovalskyi, Dmytro; Lebourgeois, Matthew; Letts, James; Macneill, Ian; Padhi, Sanjay; Palmer, Christopher; Pieri, Marco; Sani, Matteo; Sharma, Vivek; Simon, Sean; Sudano, Elizabeth; Tadel, Matevz; Tu, Yanjun; Vartak, Adish; Wasserbaech, Steven; Würthwein, Frank; Yagil, Avraham; Yoo, Jaehyeok; Barge, Derek; Bradmiller-Feld, John; Campagnari, Claudio; Danielson, Thomas; Dishaw, Adam; Flowers, Kristen; Franco Sevilla, Manuel; Geffert, Paul; George, Christopher; Golf, Frank; Incandela, Joe; Justus, Christopher; Magaña Villalba, Ricardo; Mccoll, Nickolas; Pavlunin, Viktor; Richman, Jeffrey; Rossin, Roberto; Stuart, David; To, Wing; West, Christopher; Apresyan, Artur; Bornheim, Adolf; Bunn, Julian; Chen, Yi; Di Marco, Emanuele; Duarte, Javier; Kcira, Dorian; Mott, Alexander; Newman, Harvey B; Pena, Cristian; Rogan, Christopher; Spiropulu, Maria; Timciuc, Vladlen; Wilkinson, Richard; Xie, Si; Zhu, Ren-Yuan; Azzolini, Virginia; Calamba, Aristotle; Carroll, Ryan; Ferguson, Thomas; Iiyama, Yutaro; Jang, Dong Wook; Paulini, Manfred; Russ, James; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Drell, Brian Robert; Ford, William T; Gaz, Alessandro; Luiggi Lopez, Eduardo; Nauenberg, Uriel; Smith, James; Stenson, Kevin; Ulmer, Keith; Wagner, Stephen Robert; Alexander, James; Chatterjee, Avishek; Chu, Jennifer; Eggert, Nicholas; Gibbons, Lawrence Kent; Hopkins, Walter; Khukhunaishvili, Aleko; Kreis, Benjamin; Mirman, Nathan; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Ryd, Anders; Salvati, Emmanuele; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Tucker, Jordan; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Apollinari, Giorgio; Bauerdick, Lothar AT; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C; Burkett, Kevin; Butler, Joel Nathan; Chetluru, Vasundhara; Cheung, Harry; Chlebana, Frank; Cihangir, Selcuk; Elvira, Victor Daniel; Fisk, Ian; Freeman, Jim; Gao, Yanyan; Gottschalk, Erik; Gray, Lindsey; Green, Dan; Grünendahl, Stefan; Gutsche, Oliver; Hare, Daryl; Harris, Robert M; Hirschauer, James; Hooberman, Benjamin; Jindariani, Sergo; Johnson, Marvin; Joshi, Umesh; Kaadze, Ketino; Klima, Boaz; Kwan, Simon; Linacre, Jacob; Lincoln, Don; Lipton, Ron; Liu, Tiehui; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Martinez Outschoorn, Verena Ingrid; Maruyama, Sho; Mason, David; McBride, Patricia; Mishra, Kalanand; Mrenna, Stephen; Musienko, Yuri; Nahn, Steve; Newman-Holmes, Catherine; O'Dell, Vivian; Prokofyev, Oleg; Ratnikova, Natalia; Sexton-Kennedy, Elizabeth; Sharma, Seema; Soha, Aron; Spalding, William J; Spiegel, Leonard; Taylor, Lucas; Tkaczyk, Slawek; Tran, Nhan Viet; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitbeck, Andrew; Whitmore, Juliana; Wu, Weimin; Yang, Fan; Yun, Jae Chul; Acosta, Darin; Avery, Paul; Bourilkov, Dimitri; Cheng, Tongguang; Das, Souvik; De Gruttola, Michele; Di Giovanni, Gian Piero; Dobur, Didar; Field, Richard D; Fisher, Matthew; Fu, Yu; Furic, Ivan-Kresimir; Hugon, Justin; Kim, Bockjoo; Konigsberg, Jacobo; Korytov, Andrey; Kropivnitskaya, Anna; Kypreos, Theodore; Low, Jia Fu; Matchev, Konstantin; Milenovic, Predrag; Mitselmakher, Guenakh; Muniz, Lana; Rinkevicius, Aurelijus; Shchutska, Lesya; Skhirtladze, Nikoloz; Snowball, Matthew; Yelton, John; Zakaria, Mohammed; Gaultney, Vanessa; Hewamanage, Samantha; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Todd; Askew, Andrew; Bochenek, Joseph; Chen, Jie; Diamond, Brendan; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Johnson, Kurtis F; Prosper, Harrison; Veeraraghavan, Venkatesh; Weinberg, Marc; Baarmand, Marc M; Dorney, Brian; Hohlmann, Marcus; Kalakhety, Himali; Yumiceva, Francisco; Adams, Mark Raymond; Apanasevich, Leonard; Bazterra, Victor Eduardo; Betts, Russell Richard; Bucinskaite, Inga; Cavanaugh, Richard; Evdokimov, Olga; Gauthier, Lucie; Gerber, Cecilia Elena; Hofman, David Jonathan; Khalatyan, Samvel; Kurt, Pelin; Moon, Dong Ho; O'Brien, Christine; Silkworth, Christopher; Turner, Paul; Varelas, Nikos; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Clarida, Warren; Dilsiz, Kamuran; Duru, Firdevs; Haytmyradov, Maksat; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Ogul, Hasan; Onel, Yasar; Ozok, Ferhat; Penzo, Aldo; Rahmat, Rahmat; Sen, Sercan; Tan, Ping; Tiras, Emrah; Wetzel, James; Yetkin, Taylan; Yi, Kai; Barnett, Bruce Arnold; Blumenfeld, Barry; Bolognesi, Sara; Fehling, David; Gritsan, Andrei; Maksimovic, Petar; Martin, Christopher; Swartz, Morris; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Gray, Julia; Kenny III, Raymond Patrick; Murray, Michael; Noonan, Daniel; Sanders, Stephen; Sekaric, Jadranka; Stringer, Robert; Wang, Quan; Wood, Jeffrey Scott; Barfuss, Anne-Fleur; Chakaberia, Irakli; Ivanov, Andrew; Khalil, Sadia; Makouski, Mikhail; Maravin, Yurii; Saini, Lovedeep Kaur; Shrestha, Shruti; Svintradze, Irakli; Gronberg, Jeffrey; Lange, David; Rebassoo, Finn; Wright, Douglas; Baden, Drew; Calvert, Brian; Eno, Sarah Catherine; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G; Kolberg, Ted; Lu, Ying; Marionneau, Matthieu; Mignerey, Alice; Pedro, Kevin; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Tonwar, Suresh C; Apyan, Aram; Barbieri, Richard; Bauer, Gerry; Busza, Wit; Cali, Ivan Amos; Chan, Matthew; Di Matteo, Leonardo; Dutta, Valentina; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Gulhan, Doga; Klute, Markus; Lai, Yue Shi; Lee, Yen-Jie; Levin, Andrew; Luckey, Paul David; Ma, Teng; Paus, Christoph; Ralph, Duncan; Roland, Christof; Roland, Gunther; Stephans, George; Stöckli, Fabian; Sumorok, Konstanty; Velicanu, Dragos; Veverka, Jan; Wyslouch, Bolek; Yang, Mingming; Yoon, Sungho; Zanetti, Marco; Zhukova, Victoria; Dahmes, Bryan; De Benedetti, Abraham; Gude, Alexander; Kao, Shih-Chuan; Klapoetke, Kevin; Kubota, Yuichi; Mans, Jeremy; Pastika, Nathaniel; Rusack, Roger; Singovsky, Alexander; Tambe, Norbert; Turkewitz, Jared; Acosta, John Gabriel; Cremaldi, Lucien Marcus; Kroeger, Rob; Oliveros, Sandra; Perera, Lalith; Sanders, David A; Summers, Don; Avdeeva, Ekaterina; Bloom, Kenneth; Bose, Suvadeep; Claes, Daniel R; Dominguez, Aaron; Gonzalez Suarez, Rebeca; Keller, Jason; Knowlton, Dan; Kravchenko, Ilya; Lazo-Flores, Jose; Malik, Sudhir; Meier, Frank; Snow, Gregory R; Dolen, James; Godshalk, Andrew; Iashvili, Ia; Jain, Supriya; Kharchilava, Avto; Kumar, Ashish; Rappoccio, Salvatore; Alverson, George; Barberis, Emanuela; Baumgartel, Darin; Chasco, Matthew; Haley, Joseph; Massironi, Andrea; Nash, David; Orimoto, Toyoko; Trocino, Daniele; Wood, Darien; Zhang, Jinzhong; Anastassov, Anton; Hahn, Kristan Allan; Kubik, Andrew; Lusito, Letizia; Mucia, Nicholas; Odell, Nathaniel; Pollack, Brian; Pozdnyakov, Andrey; Schmitt, Michael; Stoynev, Stoyan; Sung, Kevin; Velasco, Mayda; Won, Steven; Berry, Douglas; Brinkerhoff, Andrew; Chan, Kwok Ming; Drozdetskiy, Alexey; Hildreth, Michael; Jessop, Colin; Karmgard, Daniel John; Kellams, Nathan; Kolb, Jeff; Lannon, Kevin; Luo, Wuming; Lynch, Sean; Marinelli, Nancy; Morse, David Michael; Pearson, Tessa; Planer, Michael; Ruchti, Randy; Slaunwhite, Jason; Valls, Nil; Wayne, Mitchell; Wolf, Matthias; Woodard, Anna; Antonelli, Louis; Bylsma, Ben; Durkin, Lloyd Stanley; Flowers, Sean; Hill, Christopher; Hughes, Richard; Kotov, Khristian; Ling, Ta-Yung; Puigh, Darren; Rodenburg, Marissa; Smith, Geoffrey; Vuosalo, Carl; Winer, Brian L; Wolfe, Homer; Wulsin, Howard Wells; Berry, Edmund; Elmer, Peter; Halyo, Valerie; Hebda, Philip; Hunt, Adam; Jindal, Pratima; Koay, Sue Ann; Lujan, Paul; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Piroué, Pierre; Quan, Xiaohang; Raval, Amita; Saka, Halil; Stickland, David; Tully, Christopher; Werner, Jeremy Scott; Zenz, Seth Conrad; Zuranski, Andrzej; Brownson, Eric; Lopez, Angel; Mendez, Hector; Ramirez Vargas, Juan Eduardo; Alagoz, Enver; Benedetti, Daniele; Bolla, Gino; Bortoletto, Daniela; De Mattia, Marco; Everett, Adam; Hu, Zhen; Jha, Manoj; Jones, Matthew; Jung, Kurt; Kress, Matthew; Leonardo, Nuno; Lopes Pegna, David; Maroussov, Vassili; Merkel, Petra; Miller, David Harry; Neumeister, Norbert; Radburn-Smith, Benjamin Charles; Shipsey, Ian; Silvers, David; Svyatkovskiy, Alexey; Wang, Fuqiang; Xie, Wei; Xu, Lingshan; Yoo, Hwi Dong; Zablocki, Jakub; Zheng, Yu; Parashar, Neeti; Adair, Antony; Akgun, Bora; Ecklund, Karl Matthew; Geurts, Frank JM; Li, Wei; Michlin, Benjamin; Padley, Brian Paul; Redjimi, Radia; Roberts, Jay; Zabel, James; Betchart, Burton; Bodek, Arie; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Ferbel, Thomas; Garcia-Bellido, Aran; Goldenzweig, Pablo; Han, Jiyeon; Harel, Amnon; Miner, Daniel Carl; Petrillo, Gianluca; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Ciesielski, Robert; Demortier, Luc; Goulianos, Konstantin; Lungu, Gheorghe; Malik, Sarah; Mesropian, Christina; Arora, Sanjay; Barker, Anthony; Chou, John Paul; Contreras-Campana, Christian; Contreras-Campana, Emmanuel; Duggan, Daniel; Ferencek, Dinko; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Lath, Amitabh; Panwalkar, Shruti; Park, Michael; Patel, Rishi; Rekovic, Vladimir; Robles, Jorge; Salur, Sevil; Schnetzer, Steve; Seitz, Claudia; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Thomassen, Peter; Walker, Matthew; Rose, Keith; Spanier, Stefan; Yang, Zong-Chang; York, Andrew; Bouhali, Othmane; Eusebi, Ricardo; Flanagan, Will; Gilmore, Jason; Kamon, Teruki; Khotilovich, Vadim; Krutelyov, Vyacheslav; Montalvo, Roy; Osipenkov, Ilya; Pakhotin, Yuriy; Perloff, Alexx; Roe, Jeffrey; Rose, Anthony; Safonov, Alexei; Sakuma, Tai; Suarez, Indara; Tatarinov, Aysen; Toback, David; Akchurin, Nural; Cowden, Christopher; Damgov, Jordan; Dragoiu, Cosmin; Dudero, Phillip Russell; Faulkner, James; Kovitanggoon, Kittikul; Kunori, Shuichi; Lee, Sung Won; Libeiro, Terence; Volobouev, Igor; Appelt, Eric; Delannoy, Andrés G; Greene, Senta; Gurrola, Alfredo; Johns, Willard; Maguire, Charles; Mao, Yaxian; Melo, Andrew; Sharma, Monika; Sheldon, Paul; Snook, Benjamin; Tuo, Shengquan; Velkovska, Julia; Arenton, Michael Wayne; Boutle, Sarah; Cox, Bradley; Francis, Brian; Goodell, Joseph; Hirosky, Robert; Ledovskoy, Alexander; Li, Hengne; Lin, Chuanzhe; Neu, Christopher; Wood, John; Gollapinni, Sowjanya; Harr, Robert; Karchin, Paul Edmund; Kottachchi Kankanamge Don, Chamath; Lamichhane, Pramod; Belknap, Donald; Borrello, Laura; Carlsmith, Duncan; Cepeda, Maria; Dasu, Sridhara; Duric, Senka; Friis, Evan; Grothe, Monika; Hall-Wilton, Richard; Herndon, Matthew; Hervé, Alain; Klabbers, Pamela; Klukas, Jeffrey; Lanaro, Armando; Lazaridis, Christos; Levine, Aaron; Loveless, Richard; Mohapatra, Ajit; Ojalvo, Isabel; Perry, Thomas; Pierro, Giuseppe Antonio; Polese, Giovanni; Ross, Ian; Sarangi, Tapas; Savin, Alexander; Smith, Wesley H; Woods, Nathaniel
2014-01-01
The discovery of a new boson with a mass of approximately 125 GeV in 2012 at the LHC has heralded a new era in understanding the nature of electroweak symmetry breaking and possibly completing the standard model of particle physics. Since the first observation in decays to gamma-gamma, WW, and ZZ boson pairs, an extensive set of measurements of the mass and couplings to W and Z bosons, as well as multiple tests of the spin-parity quantum numbers, have revealed that the properties of the new boson are consistent with those of the long-sought agent responsible for electroweak symmetry breaking. An important open question is whether the new particle also couples to fermions, and in particular to down-type fermions, since the current measurements mainly constrain the couplings to the up-type top quark. Determination of the couplings to down-type fermions requires direct measurement of the corresponding Higgs boson decays, as recently reported by the CMS experiment in the study of Higgs decays to bottom quarks and...
Invisible decays of the heavier Higgs boson in the minimal supersymmetric standard model
Ananthanarayan, B.; Lahiri, Jayita; Pandita, P. N.
2015-01-01
We consider the possibility that the heavier CP-even Higgs boson~($H^0$) in the minimal supersymmetric standard model (MSSM) decays invisibly into neutralinos in the light of the recent discovery of the 126 GeV resonance at the CERN Large Hadron Collider (LHC). For this purpose we consider the minimal supersymmetric standard model with universal, non-universal and arbitrary boundary conditions on the supersymmetry breaking gaugino mass parameters at the grand unified scale. Typically, scenari...
Particles and the universe from the Ionian school to the Higgs boson and beyond
Narison, Stephan
2016-01-01
This book aims to present the history and developments of particle physics from the introduction of the notion of particles by the Ionian school until the discovery of the Higgs boson at LHC in 2012 and discuss the future developments of the field. The evolution of accelerators where different particles have been discovered is reviewed and details about the CERN accelerators are presented. A short presentation of some features of astrophysics and its connection to particle physics is also included.
A semiclassical approach for the Higgs boson
Fariborz, Amir H; Schechter, Joseph
2014-01-01
Starting from the equations of motion of the fields involved in a theory with spontaneous symmetry breaking and by making simple assumptions regarding their behavior we derive simple tree level relations between the mass of the Higgs boson in the theory and the masses of the gauge bosons corresponding to the broken generators. We show that these mass relations have a clear meaning if both the scalars and the gauge bosons are composite states made of two fermions.
Probing anomalous gauge boson couplings at LEP
International Nuclear Information System (INIS)
We bound anomalous gauge boson couplings using LEP data for the Z → bar ∫∫ partial widths. We use an effective field theory formalism to compute the one-loop corrections resulting from non-standard model three and four gauge boson vertices. We find that measurements at LEP constrain the three gauge boson couplings at a level comparable to that obtainable at LEPII
Fermionic subspaces of the bosonic string
Energy Technology Data Exchange (ETDEWEB)
Chattaraputi, Auttakit [Department of Physics, University of Chulalongkorn, Bangkok 10330 (Thailand); Englert, Francois [Service de Physique Theorique, Universite Libre de Bruxelles, Campus Plaine, CP 225, Boulevard du Triomphe, B-1050 Bruxelles (Belgium); Houart, Laurent [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles, Campus Plaine CP 231, Boulevard du Triomphe, B-1050 Brussells (Belgium); Taormina, Anne [Department of Mathematical Sciences, University of Durham, South Road, DH1 3LE Durham (United Kingdom)
2003-06-21
A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates spacetime fermions out of bosons dynamically within the framework of bosonic string theory.
Fermionic Subspaces of the Bosonic String
Chattaraputi, A; Houart, L; Taormina, A; Chattaraputi, Auttakit; Englert, Francois; Houart, Laurent; Taormina, Anne
2003-01-01
A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates space-time fermions out of bosons dynamically within the framework of bosonic string theory.
Fermionic Subspaces of the Bosonic String
Chattaraputi, A.; Englert, F.; Houart, L.; Taormina, A.
A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates space-time fermions out of bosons dynamically within the framework of bosonic string theory.
Testing the Higgs Boson Coupling to Gluons
Langenegger, Urs; Strebel, Ivo
2015-01-01
We study the possibility to separate in gluon fusion loop-induced Higgs boson production from point-like production. The Higgs boson is reconstructed in the Hgg final state at very large transverse momentum. Using the Higgs boson yields (normalized to the overall rate) and the shape of the Higgs boson pt distribution the two hypotheses can be separated with 2 standard deviations with an integrated luminosity of about 500 fb^-1. The largest experimental uncertainty affecting this estimate is the background event yield. The theoretical uncertainties from missing top mass effects are large, but can be decreased with dedicated calculations.
Mele, S
2004-01-01
The high-energy and high-luminosity data-taking campaigns of the LEP e+e- collider provided the four collaborations, ALEPH, DELPHI, L3 and OPAL, with about 50 000 W-boson pairs and about a thousand singly-produced W bosons. This unique data sample has an unprecedented reach in probing some aspects of the Standard Model of the electroweak interactions, and this article reviews several achievements in the understanding of W-boson physics at LEP. The measurements of the cross sections for W-boson production are discussed, together with their implication on the existence of the coupling between Z and W bosons. The precision measurements of the magnitude of triple gauge-boson couplings are presented. The observation of the longitudinal helicity component of the W-boson spin, related to the mechanism of electroweak symmetry breaking, is described together with the techniques used to probe the CP and CPT symmetries in the W-boson system. A discussion on the intricacies of the measurement of the mass of the W boson, ...
Rotating Boson Stars and Q-Balls
Kleihaus, B; List, M; Kleihaus, Burkhard; Kunz, Jutta; List, Meike
2005-01-01
We consider axially symmetric, rotating boson stars. Their flat space limits represent spinning Q-balls. We discuss their properties and determine their domain of existence. Q-balls and boson stars are stationary solutions and exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the boson stars. We address the flat space limit and the limit of strong gravitational coupling. For comparison we also determine the properties of spherically symmetric Q-balls and boson stars.
The Discovery of the W and Z Particles
Di Lella, Luigi
2015-01-01
This article describes the scientific achievements that led to the discovery of the weak intermediate vector bosons, W± and Z, from the original proposal to modify an existing high-energy proton accelerator into a proton–antiproton collider and its implementation at CERN, to the design, construction and operation of the detectors which provided the first evidence for the production and decay of these two fundamental particles.
Phase transitions in Bose-Fermi-Hubbard model in the heavy fermion limit: Hard-core boson approach
Directory of Open Access Journals (Sweden)
I.V. Stasyuk
2015-12-01
Full Text Available Phase transitions are investigated in the Bose-Fermi-Hubbard model in the mean field and hard-core boson approximations for the case of infinitely small fermion transfer and repulsive on-site boson-fermion interaction. The behavior of the Bose-Einstein condensate order parameter and grand canonical potential is analyzed as functions of the chemical potential of bosons at zero temperature. The possibility of change of order of the phase transition to the superfluid phase in the regime of fixed values of the chemical potentials of Bose- and Fermi-particles is established. The relevant phase diagrams are built.
DEFF Research Database (Denmark)
Vester, Jan Kjølhede; Glaring, Mikkel Andreas; Stougaard, Peter
2014-01-01
to these conditions. Since only a small fraction of the total microbial diversity can be cultured in the laboratory, a combined approach involving functional screening of a strain collection and a metagenomic library was undertaken for discovery of novel enzymes from the ikaite columns.Results: A strain collection......-amylases and β-galactosidases were characterized in more detail with respect to temperature and pH profiles and one of the β-galactosidases, BGalI17E2, was able to hydrolyze lactose at 5°C. A metagenome sequence of the expression library indicated that the majority of enzymatic activities were not detected....../or alkaline-active enzymes of industrial relevance were identified in the culture based approach and the majority of the enzyme-producing isolates were closely related to previously characterized strains. The function-based metagenomic approach, on the other hand, identified several enzymes (β...
Chen, Xinde; Wang, Kai; Xu, Wenwei; Ma, Quanxin; Chen, Minli; Du, Lili; Mo, Mingguang; Wang, Yiping; Shen, Jianhua
2016-03-24
Lipoprotein-associated phospholipase A2 (Lp-PLA2) is considered to be a promising therapeutic target for several inflammation-associated diseases. Herein, we describe the discovery of a series of pyrimidone derivatives as Lp-PLA2 inhibitors. Systematic structural modifications led to the identification of several pyrimidone compounds with promising in vitro inhibitory potency and pharmacokinetic properties. Compound 14c, selected for in vivo evaluation, demonstrated decent pharmacokinetic profiles and robust inhibitory potency against Lp-PLA2 in Sprague-Dawley (SD) rats. Furthermore, 14c significantly inhibited retinal thickening in STZ-induced diabetic SD rats as a model of diabetic macular edema (DME) after oral dosing for 4 weeks. Taken together, these results suggested that 14c can serve as a valuable lead in the search for new Lp-PLA2 inhibitors for prevention and/or treatment of DME. PMID:26927682
Directory of Open Access Journals (Sweden)
Bradley J. Blitvich
2015-04-01
Full Text Available There has been a dramatic increase in the number of insect-specific flaviviruses (ISFs discovered in the last decade. Historically, these viruses have generated limited interest due to their inability to infect vertebrate cells. This viewpoint has changed in recent years because some ISFs have been shown to enhance or suppress the replication of medically important flaviviruses in co-infected mosquito cells. Additionally, comparative studies between ISFs and medically important flaviviruses can provide a unique perspective as to why some flaviviruses possess the ability to infect and cause devastating disease in humans while others do not. ISFs have been isolated exclusively from mosquitoes in nature but the detection of ISF-like sequences in sandflies and chironomids indicates that they may also infect other dipterans. ISFs can be divided into two distinct phylogenetic groups. The first group currently consists of approximately 12 viruses and includes cell fusing agent virus, Kamiti River virus and Culex flavivirus. These viruses are phylogenetically distinct from all other known flaviviruses. The second group, which is apparently not monophyletic, currently consists of nine viruses and includes Chaoyang virus, Nounané virus and Lammi virus. These viruses phylogenetically affiliate with mosquito/vertebrate flaviviruses despite their apparent insect-restricted phenotype. This article provides a review of the discovery, host range, mode of transmission, superinfection exclusion ability and genomic organization of ISFs. This article also attempts to clarify the ISF nomenclature because some of these viruses have been assigned more than one name due to their simultaneous discoveries by independent research groups.
Towards an alternative unification of massless and massive vector bosons
International Nuclear Information System (INIS)
A possible extension of the gauge principle is presented where two distinct gauge potentials are introduced in association with a single U(1) gauge group, each of them being taken to interact with a different kind of matter field. In such a picture, a massive vector boson naturally shows up in the physical spectrum. A massive photon without Higgs can be introduced. Renormalizability is seen to be a feature of the model. Possible supersymmetrizations are also contemplated. (Author)
Boson Pairs in a One-dimensional Split Trap
Murphy, Domhnall; McCann, Jim; J. Goold; Busch, T
2007-01-01
We describe the properties of a pair of ultracold bosonic atoms in a one-dimensional harmonic trapping potential with a tunable zero-ranged barrier at the trap center. The full characterization of the ground state is done by calculating the reduced single-particle density, the momentum distribution, and the two-particle entanglement. We derive several analytical expressions in the limit of infinite repulsion (Tonks-Girardeau limit) and extend the treatment to finite interparticle interactions...
International Nuclear Information System (INIS)
The LHC (Large Hadron Collider) provides proton-proton collisions to CERN (European Organization for Nuclear Research) experiments at a 7 TeV center of mass energy since March 2010. The LHC has been designed in particular to allow the Higgs boson searches, particle predicted in the standard model but still not discovered until today, in the whole mass range where it is expected. This work is a contribution to the Higgs boson searches in CMS (Compact Muon Solenoid), one of the four big detectors at LHC. The thesis develops several tools which allow to measure the backgrounds and to improve the discovery potential. A new tool for recovery of photons emitted by leptons in the final state: H → ZZ(*) → 4l (l=e, μ) has been developed in this thesis. This method that recovers a variable number of photons per event, performs better than the method previously used in CMS and improves Z0 and Higgs boson mass resolution. A 5% gain on the significance to observe a Higgs boson in this channel is reached. The second part of this work deals with studies of the backgrounds and the search for a light Higgs boson (110 H 0 discrimination with a neural network has been developed to reject photons coming from π0 decays, copiously produced in QCD jets. The neural network performance is examined in details. The neural network is then used as 'template' variable to measure γ+X process in data with 10 nb-1 of integrated luminosity. The measurement of γγ+X process is also prepared with simulation in the hypothesis of a 10 pb-1 luminosity. Taking into account higher order kinematic effects is necessary to perform the best prediction of H → γγ signal and backgrounds. In the thesis this is carried out with a reweighing method, at NNLO for gg → H → γγ process and for the first time at NLO for γγ+X process, in both cases with doubly differential distributions. Reweighing procedure and γ/π0 neural network are then integrated in the H → γγ analysis to improve CMS
The standard model of particle physics - From the electron to the Higgs boson
International Nuclear Information System (INIS)
This bibliographical note presents the content and proposes the table of content of a book which gives a historical review of the development of the standard model of particle physics which supposes that any matter is made of quarks and leptons (1/2 spin point particles). The chapters address particle physics and the concept of matter, the early stages of the modern matter atomic theory, the photon, photon-related discoveries between 1985 and 1902, the discovery of the electron, radioactivity and radiations, the discovery of the proton by Rutherford, antiparticles, cosmic rays and the discovery of the positron, the Compton effect, the spin, the wave-particle duality, quantum electrodynamics, Fermi theory of β radioactivity, the discovery of the neutron, the Yukawa theory, strangeness, Yang and Mills theory and gauge theories, quarks, full formulation of the weak interaction and the discovery of W and Z bosons, discovery of the tau lepton, quantum chromodynamics, discovery of the massive neutrinos, the Brout-Englert-Higgs mechanism, the four interactions, the standard model and its limitations
Landau-Yang theorem and decays of a Z' boson into two Z bosons.
Keung, Wai-Yee; Low, Ian; Shu, Jing
2008-08-29
We study the decay of a Z' boson into two Z bosons by extending the Landau-Yang theorem to a parent particle decaying into two Z bosons. For a spin-1 parent the theorem predicts that (1) there are only two possible couplings and (2) the normalized differential cross section depends on kinematics only through a phase shift in the azimuthal angle between the two decay planes of the Z boson. When the parent is a Z' the two possible couplings are anomaly induced and CP violating, respectively. At the CERN Large Hadron Collider their effects could be disentangled when both Z bosons decay leptonically. PMID:18851602
Precision Higgs Boson Physics and Implications for Beyond the Standard Model Physics Theories
International Nuclear Information System (INIS)
The discovery of the Higgs boson is one of science's most impressive recent achievements. We have taken a leap forward in understanding what is at the heart of elementary particle mass generation. We now have a significant opportunity to develop even deeper understanding of how the fundamental laws of nature are constructed. As such, we need intense focus from the scientific community to put this discovery in its proper context, to realign and narrow our understanding of viable theory based on this positive discovery, and to detail the implications the discovery has for theories that attempt to answer questions beyond what the Standard Model can explain. This project's first main object is to develop a state-of-the-art analysis of precision Higgs boson physics. This is to be done in the tradition of the electroweak precision measurements of the LEP/SLC era. Indeed, the electroweak precision studies of the past are necessary inputs to the full precision Higgs program. Calculations will be presented to the community of Higgs boson observables that detail just how well various couplings of the Higgs boson can be measured, and more. These will be carried out using state-of-the-art theory computations coupled with the new experimental results coming in from the LHC. The project's second main objective is to utilize the results obtained from LHC Higgs boson experiments and the precision analysis, along with the direct search studies at LHC, and discern viable theories of physics beyond the Standard Model that unify physics to a deeper level. Studies will be performed on supersymmetric theories, theories of extra spatial dimensions (and related theories, such as compositeness), and theories that contain hidden sector states uniquely accessible to the Higgs boson. In addition, if data becomes incompatible with the Standard Model's low-energy effective lagrangian, new physics theories will be developed that explain the anomaly and put it into a more
Higgs-like boson at 750 GeV and genesis of baryons
Davoudiasl, Hooman; Giardino, Pier Paolo; Zhang, Cen
2016-07-01
We propose that the diphoton excess at 750 GeV reported by ATLAS and CMS is due to the decay of an exo-Higgs scalar η associated with the breaking of a new S U (2 )e symmetry, dubbed exo-spin. New fermions, exo-quarks and exo-leptons, get TeV-scale masses through Yukawa couplings with η and generate its couplings to gluons and photons at one loop. The matter content of our model yields a B -L anomaly under S U (2 )e, whose breaking we assume entails a first-order phase transition. A nontrivial B -L asymmetry may therefore be generated in the early Universe, potentially providing a baryogenesis mechanism through the Standard Model (SM) sphaleron processes. The spontaneous breaking of S U (2 )e can, in principle, directly lead to electroweak symmetry breaking, thereby accounting for the proximity of the mass scales of the SM Higgs and the exo-Higgs. Our model can be distinguished from those comprising a singlet scalar and vector fermions by the discovery of TeV scale exo-vector bosons, corresponding to the broken S U (2 )e generators, at the LHC.
LHC accessible second Higgs boson in the left-right model
Mohapatra, Rabindra N.; Zhang, Yongchao
2014-03-01
A second Higgs doublet arises naturally as a parity partner of the standard model (SM) Higgs, once the SM is extended to its left-right symmetric version (LRSM) to understand the origin of parity violation in weak interactions, as well as to accommodate small neutrino masses via the seesaw mechanism. The flavor-changing neutral Higgs (FCNH) effects in the minimal version of this model (LRSM), however, push the second Higgs mass to more than 15 TeV, making it inaccessible at the LHC. Furthermore, since the second Higgs mass is directly linked to the WR mass, discovery of a "low" mass WR (MWR≤5-6 TeV) at the LHC would require values for some Higgs self-couplings larger than 1. In this paper we present an extension of LRSM by adding a vectorlike SU(2)R quark doublet which weakens the FCNH constraints, allowing the second Higgs mass to be near or below the TeV range and a third neutral Higgs below 3 TeV for a WR mass below 5 TeV. It is then possible to search for these heavier Higgs bosons at the LHC without conflicting with FCNH constraints. A right-handed WR mass in the few TeV range is quite natural in this class of models without having to resort to large scalar coupling parameters. The CKM mixings are intimately linked to the vectorlike quark mixings with the known quarks, which is the main reason why the constraints on the second Higgs mass are relaxed. We present a detailed theoretical and phenomenological analysis of this extended left-right model and point out some tests as well as its potential for discovery of a second Higgs at the LHC. Two additional features of the model are a 5/3-charged quark and a fermionic top partner with masses in the TeV range.
Electroweak Boson Production in Association with Jets
Focke, Christfried Hermann
The high energies involved in modern collider experiments lead to hadronic final states that are often boosted inside collimated jets and surrounded by soft radiation. Together with tracking and energy information from leptons and photons, these jets contain essential information about a collision event. A good theoretical understanding is vital for measurements within the Standard Model (SM) as well as for background modeling required for new physics searches. Often one is interested in hadronic final states with cuts on jets in order to reduce backgrounds. For example, by imposing a central jet veto pcut in H → WW → lnulnu one can greatly reduce contamination from tt¯ → WW bb¯. Imposing such a jet veto comes at the cost of introducing potentially large logarithms L = ln pcut/Q into the cross section (Q is the hard scale), since the cuts restrict the cancellation of soft and collinear divergences between real and virtual diagrams. There are at most two powers of L for each power of the strong coupling constant alphas and this can spoil the convergence of the perturbative series when alpha sL2 ˜ 1 . We resume these logarithmically enhanced terms to all orders within the framework of Soft-Collinear Effective Theory (SCET) in order to recover the convergence and obtain reliable predictions for several processes. Another focus of this dissertation is the application of SCET in fixed order predictions of electroweak boson production in association with an exclusive number of final state jets. We employ the N-jettiness event-shape TN to resolve the infrared singularity structure of QCD in the presence of N signal jets. This allows us to obtain the first complete next-to-next-to leading order predictions for W, Z and Higgs boson production in association with one jet.
On Nonlinear Bosonic Coherent States
Genovese, Marco; Rasetti, Mario
2009-01-01
Nonlinear coherent states are an interesting resource for quantum technologies. Here we investigate some critical features of the single-boson nonlinear coherent states, which are theoretically constructed as eigenstates of the annihilation operator and experimentally realized as stationary states of a trapped laser-driven ion. We show that the coherence and the minimum-uncertainty properties of such states are broken for values of the Lamb-Dicke parameter corresponding to the roots of the Laguerre polynomials, which enter their explicit expression. The case of the multiboson nonlinear coherent states is also discussed.
Energy Technology Data Exchange (ETDEWEB)
Varganov, Alexei Valerievich
2004-04-01
The theory that describes the fundamental particle interactions is called the Standard Model, which is a gauge field theory that comprises the Glashow-Weinberg-Salam model [1, 2, 3] of the weak and electromagnetic interactions and quantum chromodynamics (QCD) [4, 5, 6], the theory of the strong interactions. The discovery of the W [7, 8] and Z [9, 10] bosons in 1983 by the UA1 and UA2 collaborations at the CERN p{bar p} collider provided a direct confirmation of the unification of the weak and electromagnetic interactions. Since then, many experiments have refined our understanding of the characteristics of the W and Z bosons.
Buchmüller, O L; Thompson, J C
2002-01-01
the status of the measurement of the W boson mass at LEP-2 is reviewed. Properties of the W such as branching ration into quarks and leptons and couplings to other neutral gauge bosons are reported. 4-fermion production cross-sections in e sup + e sup - collisions are also presented. (authors)
Analysis of boson cascade laser characteristics
Ivanov, K. A.; Kaliteevskaya, N. A.; Gubaidullin, A. R.; Kaliteevski, M. A.
2015-11-01
The dependence of the level population on pumping in a boson cascade laser has been theoretically studied. Analytical expressions for the population of various cascade levels and the terahertz mode below and above the pumping threshold are obtained. Formulas for the pumping threshold and external quantum efficiency of the boson cascade laser are derived.
Jalilian-Marian, Jamal
1994-01-01
We study radiative decay modes of the Z-boson into heavy quark bound states. We find that the widths for these decays are extremely small. We conclude that these decays will not be detectable for the time being unless there is a significant increase in the number of Z-bosons produced at the electron- positron colliders.
Diffractive Higgs Boson photoproduction in peripheral collisions
International Nuclear Information System (INIS)
An alternative process is proposed for the diffractive Higgs boson production inspired in the Durham model, exploring it through the photon-proton interaction. In this sense, we estimate the production cross section of the Higgs boson, comparing some sets of parton distributions in the proton and confronting this results with those from other processes. (author)
Goldstone Bosons as Fractional Cosmic Neutrinos
Weinberg, Steven
2013-01-01
It is suggested that Goldstone bosons may be masquerading as fractional cosmic neutrinos, contributing about 0.39 to what is reported as the effective number of neutrino types in the era before recombination. The broken symmetry associated with these Goldstone bosons is further speculated to be the conservation of the particles of dark matter.
Zanzi, Daniele; Kortner, Sandra
The discovery of a Higgs boson in di-boson decays, the evidence of its decays into fermion pairs and the compatibility of its measured properties with the Standard Model predictions support the electroweak symmetry breaking mechanism of the Standard Model. The topic of this thesis is the search for the Higgs boson decays into a pair of $\\tau$ leptons, important for probing the coupling of the Higgs boson to fermions. The search is performed in final states where both $\\tau$ leptons decay hadronically using $4.6\\,\\rm{fb}^{-1}$ and $20.3\\,\\rm{fb}^{-1}$ of data collected by the ATLAS detector in proton-proton collisions at the Large Hadron Collider at center-of-mass energies of 7 and 8 TeV, respectively. The signal selection is optimised for events with highly boosted Higgs bosons produced via gluon fusion with additional jet or via vector boson fusion. In order to reduce systematic uncertainties, the major background contributions from $Z\\to\\tau\\tau$ and multi-jet production processes have been measured using s...
Electroweak gauge boson polarisation at the LHC
Stirling, W J
2012-01-01
We study the polarisation of gauge bosons produced at the LHC. Polarisation effects for W bosons manifest themselves in the angular distributions of the lepton and in the distributions of lepton transverse momentum and missing transverse energy. The distributions also depend on the selection cuts, with kinematic effects competing with polarisation effects. The polarisation is discussed for a range of different processes producing W bosons: W+jets, W from top (single and pair) production, W pair production and W production in association with a Z or Higgs boson. The relative contributions of the different polarisation states varies from process to process, reflecting the dynamics of the underlying hard-scattering process. We also present results for the polarisation of the Z boson produced in association with QCD jets at the LHC, and comment on the differences between W and Z production.
The Boson peak in supercooled water.
Kumar, Pradeep; Wikfeldt, K Thor; Schlesinger, Daniel; Pettersson, Lars G M; Stanley, H Eugene
2013-01-01
We perform extensive molecular dynamics simulations of the TIP4P/2005 model of water to investigate the origin of the Boson peak reported in experiments on supercooled water in nanoconfined pores, and in hydration water around proteins. We find that the onset of the Boson peak in supercooled bulk water coincides with the crossover to a predominantly low-density-like liquid below the Widom line TW. The frequency and onset temperature of the Boson peak in our simulations of bulk water agree well with the results from experiments on nanoconfined water. Our results suggest that the Boson peak in water is not an exclusive effect of confinement. We further find that, similar to other glass-forming liquids, the vibrational modes corresponding to the Boson peak are spatially extended and are related to transverse phonons found in the parent crystal, here ice Ih. PMID:23771033
Search for new heavy charged gauge bosons
Energy Technology Data Exchange (ETDEWEB)
Magass, Carsten Martin [RWTH Aachen Univ. (Germany)
2007-11-02
Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W' decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb^{-1}. Since no significant excess is observed in the data, an upper limit is set on the production cross section times branching fraction σ_{W'}xBr (W' → ev). Using this limit, a W' boson with mass below ~1 TeV can be excluded at the 95% confidence level assuming that the new boson has the same couplings to fermions as the Standard Model W boson.
Search for new heavy charged gauge bosons
Energy Technology Data Exchange (ETDEWEB)
Magass, Carsten Martin; /RWTH Aachen U.
2007-11-01
Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W{prime} decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb{sup -1}. Since no significant excess is observed in the data, an upper limit is set on the production cross section times branching fraction {sigma}{sub W{prime}}xBr (W{prime} {yields} e{nu}). Using this limit, a W{prime} boson with mass below {approx}1 TeV can be excluded at the 95% confidence level assuming that the new boson has the same couplings to fermions as the Standard Model W boson.
Orbital dynamics of binary boson star systems
International Nuclear Information System (INIS)
We extend our previous studies of head-on collisions of boson stars by considering orbiting binary boson stars. We concentrate on equal-mass binaries and study the dynamical behavior of boson/boson and boson/antiboson pairs. We examine the gravitational wave output of these binaries and compare with other compact binaries. Such a comparison lets us probe the apparent simplicity observed in gravitational waves produced by black hole binary systems. In our system of interest however, there is an additional internal freedom which plays a significant role in the system's dynamics, namely, the phase of each star. Our evolutions show rather simple behavior at early times, but large differences occur at late times for the various initial configurations
Boson Sampling for Molecular Vibronic Spectra
Huh, Joonsuk; Peropadre, Borja; McClean, Jarrod R; Aspuru-Guzik, Alán
2014-01-01
Quantum computers are expected to be more efficient in performing certain computations than any classical machine. Unfortunately, the technological challenges associated with building a full-scale quantum computer have not yet allowed the experimental verification of such an expectation. Recently, boson sampling has emerged as a problem that is suspected to be intractable on any classical computer, but efficiently implementable with a linear quantum optical setup. Therefore, boson sampling may offer an experimentally realizable challenge to the Extended Church-Turing thesis and this remarkable possibility motivated much of the interest around boson sampling, at least in relation to complexity-theoretic questions. In this work, we show that the successful development of a boson sampling apparatus would not only answer such inquiries, but also yield a practical tool for difficult molecular computations. Specifically, we show that a boson sampling device with a modified input state can be used to generate molecu...
Yu, Taozhe
2016-01-01
After the discovery of Higgs boson,the final particle in Stand Model was discovered.We are interested in the coupling between Higgs and Top quark.We define three variables to search for the ttHbb channel.
Probing the charged Higgs boson at the LHC in the CP-violating type-II 2HDM
Basso, L.; Lipniacka, A.; Mahmoudi, F.; Moretti, S.; Osland, P.; Pruna, G. M.; Purmohammadi, M.
2012-01-01
We present a phenomenological study of a CP-violating two-Higgs-doublet Model with type-II Yukawa couplings at the Large Hadron Collider (LHC). In the light of recent LHC data, we focus on the parameter space that survives the current and past experimental constraints as well as theoretical bounds on the model. Once the phenomenological scenario is set, we analyse the scope of the LHC in exploring this model through the discovery of a charged Higgs boson produced in association with a W boson...
Z' boson decay in the SU(3)L \\otimes U(1)N electroweak model with heavy leptons
Abad, David Romero; Ravinez, Orlando Pereyra
2011-01-01
Based on the expectation generated by the discovery of new particles by current colliders, we analyze the decay of the Z' boson in the frame of one of the SU(3)L \\otimes U(1)N electroweak extensions of the standard model. The main objective is calculate the decay rate of this exotic boson in the aforementioned model at the tree level. With this purpose we need to develop the gauge sector, where we find thirty-three interaction terms. Mentioned particle (Z') has not yet been observed experimen...
Neutrino Jets from High-Mass $W_R$ Gauge Bosons in TeV-Scale Left-Right Symmetric Models
Mitra, Manimala; Scott, Darren J; Spannowsky, Michael
2016-01-01
We re-examine the discovery potential at hadron colliders of high-mass right-handed (RH) gauge bosons $W_R$ - an inherent ingredient of Left-Right Symmetric Models (LRSM). We focus on the regime where the $W_R$ is very heavy compared to the heavy Majorana neutrino $N$, and investigate an alternative signature for $W_R \\rightarrow N$ decays. The produced neutrinos are highly boosted in this mass regime. Subsequently, their decays via off-shell $W_R$ bosons to jets, i.e., $N \\rightarrow \\ell^\\pm j j$ are highly collimated, forming a single neutrino jet $(j_N)$. The final-state collider signature is then $\\ell^\\pm j_N$, instead of the widely studied $\\ell^\\pm\\ell^\\pm jj$. Present search strategies are not sensitive to this hierarchical mass regime due to the breakdown of the collider signature definition. We take into account QCD corrections beyond next-to-leading order (NLO) that are important for high-mass Drell-Yan processes at the 13 TeV Large Hadron Collider (LHC). For the first time, we evaluate $W_R$ prod...
Bosonic Matrix Theory and Matrix Dbranes
Chaudhuri, S
2002-01-01
We develop new tools for an in-depth investigation of our recent proposal for Matrix Theory. We construct the anomaly-free and finite planar continuum limit of the ground state with SO(2^{13}) symmetry matching with the tadpole and tachyon free IR stable high temperature ground state of the open and closed bosonic string. The correspondence between large N limits and spacetime effective actions is demonstrated more generally for an arbitrary D25brane ground state which might include brane-antibrane pairs or NS-branes and which need not have an action formulation. Closure of the finite N matrix Lorentz algebra nevertheless requires that such a ground state is simultaneously charged under all even rank antisymmetric matrix potentials. Additional invariance under the gauge symmetry mediated by the one-form matrix potential requires a ground state charged under the full spectrum of antisymmetric (p+1)-form matrix potentials with p taking any integer value less than 26. Matrix Dbrane democracy has a beautiful larg...
International Nuclear Information System (INIS)
A Higgs boson is a particle whose existence is predicted in a class of quantum field theories in which a symmetry under a Lie group of transformations of the fields is spontaneously broken by an asymmetric vacuum state. It is a quantum of certain excitations of the order parameter. Such spontaneous symmetry breaking was first proposed as a feature of theories of elementary particles in 1960, but it has a much longer history in the contest of condensed matter theory: in ferromagnetism as early as 1928, in superfluidity and also in superconductivity. It was Nambu who in 1960 first proposed relativistic models inspired by BCS theory as a means of generating fermion masses in elementary particle physics but the hadronic models he proposed lacked the local gauge invariance of their prototype. The connection between spontaneous symmetry and Goldstone bosons in relativistic theories were formally proved in 1962 but the experimental evidence against the existence of such particles in the real world cast a doubt on the viability of Nambu's ideas. Between 1962 and 1964 a debate developed in the literature about whether the Goldstone theorem could be evaded. The resolution of this difficulty finally came in 1964, when Higgs realized that theories with a local gauge invariance fail to satisfy one of the axioms on which the 1962 proof of the Goldstone theorem depends. By the end of July 1964, Higgs had also written down the simplest field-theoretic model that is now known as the Higgs model. (A.C.)
Exclusive Higgs Boson Production with bottom quarks at Hadron Colliders
Dawson, S; Reina, L; Wackeroth, D; 10.1103/PhysRevD.69.074027
2004-01-01
We present the next-to-leading order QCD corrected rate for the production of a scalar Higgs boson with a pair of high p_T bottom and anti-bottom quarks at the Tevatron and at the Large Hadron Collider. Results are given for both the Standard Model and the Minimal Supersymmetric Standard Model. The exclusive b-bbar-h production rate is small in the Standard Model, but it can be greatly enhanced in the Minimal Supersymmetric Standard Model for large tan(beta), making b-bbar-h an important discovery mode. We find that the next-to-leading order QCD results are much less sensitive to the renormalization and factorization scales than the lowest order results, but have a significant dependence on the choice of the renormalization scheme for the bottom quark Yukawa coupling.
W Boson Production in Association with Hadronic Jets at ATLAS
Fiascaris, Maria
2010-01-01
The Large Hadron Collider (LHC) offers unprecedented opportunities to explore unknown kinematic regions and discover new Physics. Its discovery capabilities, however, strongly depend on our understanding of the Standard Model. Leptonic decays of the W boson produced in association with jets are one of the dominant backgrounds to Physics beyond the Standard Model, particularly Supersymmetry. These processes can also serve as testing ground for the theory of strong interactions. Their study is therefore of great importance at the LHC. The aim of this thesis is to prepare the essential tools for an early data measurement of W(enu) + jets processes, assuming an integrated luminosity of 100 pb^{-1}. Based on Monte Carlo simulations, several aspects of the analysis are discussed, from the treatment of backgrounds, to the calculation of electron efficiencies and acceptances. The focus is on data-driven techniques, which are going to be crucial, particularly in the early-data phase, to minimise dependence on Monte C...
On the structure, masses and thermodynamics of the W± bosons
Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.
2016-05-01
Using Newton's universal gravitational law but with gravitational instead of rest masses, and the de Broglie wavelength equation, we show by computing from first principles their mass that the W+ and W- bosons correspond to relativistic e+ -νe and e- -νe rotating pairs. This appears consistent with the fact that W+ and W- bosons are known to decay to e+ -νe and e- -νe couples, respectively. The model contains no adjustable parameters and in addition to the computed masses, potential energies, decomposition temperatures, and lifetimes, are in good agreement with experiment. This agreement can be further improved upon considering, in addition to the relativistic gravitational force, the Coulombic charge-induced dipole interactions between the charged components (positrons or electrons) and the polarizable neutrinos.
Measuring Resonance Parameters of Heavy Higgs Bosons at TESLA
Meyer, N
2003-01-01
This study investigates the potential of the TESLA Linear Collider for measuring resonance parameters of Higgs bosons beyond the mass range studied so far. The analysis is based on the reconstruction of events from the Higgsstrahlung process e+e- -> HZ. It is shown that the total width, the mass and the event rate for Higgs production can be measured from the mass spectrum in a model independent fit. Also, the branching ratios to W- and Z-bosons can be measured, assuming these are the only relevant Higgs decay modes. The simulation includes realistic detector effects and all relevant Standard Model background processes. Results are given for mH=200-320 GeV assuming 500 fb^-1 integrated luminosity at collision energies of 500 GeV.
Measuring rare and exclusive Higgs boson decays into light resonances
Chisholm, Andrew S; Nikolopoulos, Konstantinos; Spannowsky, Michael
2016-01-01
We evaluate the LHC's potential of observing Higgs boson decays into light elementary or composite resonances through their hadronic decay channels. We focus on the Higgs boson production processes with the largest cross sections, $pp\\to h$ and $pp\\to h+\\mathrm{jet}$, with subsequent decays $h \\to ZA$ or $h\\to Z\\,\\eta_c$, and comment on the production process $pp\\to hZ$. By exploiting track-based jet substructure observables and extrapolating to $3000~\\mathrm{fb}^{-1}$ we find ${\\cal BR}(h \\to ZA) \\simeq {\\cal BR}(h \\to Z \\eta_c) \\lesssim 0.02$ at 95% CL. We interpret this limit in terms of the 2HDM Type 1. We find that searches for $h\\to ZA$ are complementary to existing measurements and can constrain large parts of the currently allowed parameter space.
Goldstone bosons in the Appelquist-Terning ETC model
Balaji, B
1995-01-01
It is demonstrated that the extended technicolor model proposed recently by Appelquist and Terning has pair of potentially light U(1) Goldstone bosons coupling to ordinary matter with strength 2m_f\\over F_{\\pi}, where m_f is the mass of the fermion and F_{\\pi} \\approx 125\\,\\GeV. These Goldstone bosons could get a mass if the spontaneously broken U(1) symmetries are also explicitly broken, by physics beyond that specified in the model. An attempt to break these symmetries by embedding the model into a larger gauge group seems to be inadequate. The problem is because there are too many representations and there is a mismatch between the number of condensates and the number of gauge symmetries broken.
The Higgs boson resonance from a chiral Higgs-Yukawa model on the lattice
International Nuclear Information System (INIS)
upper and lower Higgs boson mass bound is studied. All numerical results presented in this work involve extensive finite volume analysis. In particular the Higgs boson mass significantly depends on the lattice volume and thus an extrapolation to infinite volume is inevitable. Both mass bounds are revised in the presence of a quark doublet with a mass around 700 GeV. The upper bound of the Higgs boson mass is only slightly enhanced by about 200 GeV with respect to the standard model. The lower bound however, is altered significantly by a factor of about five to ten. The strong dependence of the lower mass bound on the quark mass motivated to explore the Higgs boson mass bounds at a fixed cut off of 1500 GeV and varying quark masses. Preliminary data for the upper Higgs boson mass are presented. A detailed analysis at strong Yukawa couplings of both, the lower and the upper, mass bounds in a non perturbative fashion is certainly needed and may provide a reliable basis in favour or disfavour of a potential fourth generation of heavy quarks. (orig.)
The Higgs boson resonance from a chiral Higgs-Yukawa model on the lattice
Energy Technology Data Exchange (ETDEWEB)
Kallarackal, Jim
2011-04-28
upper and lower Higgs boson mass bound is studied. All numerical results presented in this work involve extensive finite volume analysis. In particular the Higgs boson mass significantly depends on the lattice volume and thus an extrapolation to infinite volume is inevitable. Both mass bounds are revised in the presence of a quark doublet with a mass around 700 GeV. The upper bound of the Higgs boson mass is only slightly enhanced by about 200 GeV with respect to the standard model. The lower bound however, is altered significantly by a factor of about five to ten. The strong dependence of the lower mass bound on the quark mass motivated to explore the Higgs boson mass bounds at a fixed cut off of 1500 GeV and varying quark masses. Preliminary data for the upper Higgs boson mass are presented. A detailed analysis at strong Yukawa couplings of both, the lower and the upper, mass bounds in a non perturbative fashion is certainly needed and may provide a reliable basis in favour or disfavour of a potential fourth generation of heavy quarks. (orig.)
International Nuclear Information System (INIS)
A report is given on the theoretical prediction and the experimental discovery of elementary particles from the electron to the weak intermediate vector bosons. The work of Lattes, Occhialini and Powell which put in evidence the pions predicted by Yukawa was the starting point of the modern experimental particle physics. (Author)
International Nuclear Information System (INIS)
A report is given on the theoretical prediction and the experimental discovery of elementary particles from the electron to the weak intermediate vector bosons. The work of Lattes, Occhialini and Powell which put in evidence the pions predicted by Yukawa was the starting point of the modern experimental particle physics
Farzinnia, Arsham
2015-11-01
We examine the impact of the expected reach of the LHC and the XENON1T experiments on the parameter space of the minimal classically scale invariant extension of the standard model (SM), where all the mass scales are induced dynamically by means of the Coleman-Weinberg mechanism. In this framework, the SM content is enlarged by the addition of one complex gauge-singlet scalar with a scale invariant and C P -symmetric potential. The massive pseudoscalar component, protected by the C P symmetry, forms a viable dark matter candidate, and three flavors of the right-handed Majorana neutrinos are included to account for the nonzero masses of the SM neutrinos via the seesaw mechanism. The projected constraints on the parameter space arise by applying the ATLAS heavy Higgs discovery prospects, with an integrated luminosity of 300 and 3000 fb-1 at √{s }=14 TeV , to the pseudo-Nambu-Goldstone boson of the (approximate) scale symmetry, as well as by utilizing the expected reach of the XENON1T direct detection experiment for the discovery of the pseudoscalar dark matter candidate. A null-signal discovery by these future experiments implies that vast regions of the model's parameter space can be thoroughly explored; the combined projections are expected to confine a mixing between the SM and the singlet sector to very small values while probing the viability of the TeV scale pseudoscalar's thermal relic abundance as the dominant dark matter component in the Universe. Furthermore, the vacuum stability and triviality requirements of the framework up to the Planck scale are studied, and the viable region of the parameter space is identified. The results are summarized in extensive exclusion plots, incorporating additionally the prior theoretical and experimental bounds for comparison.
International Nuclear Information System (INIS)
The CMS and ATLAS experiments at the LHC have announced the discovery of a Higgs boson with mass at approximately 125~GeV/c2 in the search for the Standard Model Higgs boson via notably the γγ and ZZ to four leptons final states. Considering the recent results on the Higgs boson searches from the LHC, we study the lightest scalar Higgs boson h1 in the Next-to-Minimal Supersymmetric Standard Model by restricting the next-to-lightest scalar Higgs boson h2 to be the observed 125~GeV/c2 state. We perform a scan over the relevant NMSSM parameter space that is favoured by low fine-tuning considerations. Moreover, we also take the experimental constraints from direct searches, B-physics observables, relic density and anomalous magnetic moment of the muon measurements as well as the theoretical considerations into account in our specific scan. We find that the signal rate in the two-photon final state for the NMSSM Higgs boson h1 with the mass range from about 80~GeV/c2 to about 122~GeV/c2 can be enhanced by a factor up to 3.5, when the Higgs boson h2 is required to be compatible with the excess from latest LHC results. This motivates the extension of the search at the LHC for the Higgs boson h1 in the diphoton final state down to masses of 80~GeV/c2, in particular with the upcoming proton-proton collision data to be taken at center-of-mass energies of 13--14~TeV
Higgs boson research in e+e- collisions
International Nuclear Information System (INIS)
This lesson is about the experimental results obtained in 1990, at LEP concerning Higgs boson research. The main topics studied are: Higgs boson research of minimal Standard Model, then beyond the minimal model, the charged Higgs boson research in 2-doublets model, and finally, neutral Higgs boson research in a specific 2-doublets model, the minimal supersymmetric standard model
Search for doubly charged Higgs bosons through VBF at the LHC, and beyond
Bambhaniya, G; Gluza, J; Jelinski, T; Szafron, R
2015-01-01
Production and decays of doubly charged Higgs bosons at the LHC and future hadron colliders triggered by vector boson fusion mechanism are discussed in the context of the Minimal Left-Right Symmetric Model. Our analysis is based on the Higgs boson mass spectrum compatible with available constraints which include FCNC effects and vacuum stability of the scalar potential. Though the parity breaking scale $v_R$ is large ($\\sim$ few TeV) and scalar masses which contribute to FCNC effects are even larger, consistent Higgs boson mass spectrum still allows us to keep doubly charged scalar masses below 1 TeV which is an interesting situation for LHC and future FCC colliders. We have shown that allowed Higgs bosons mass spectrum constrains the splittings ($M_{H_{1}^{\\pm \\pm}}-M_{H_{1}^\\pm}$), closing the possibility of $H_{1}^{\\pm\\pm}\\to W_{1}^\\pm H_{1}^\\pm$ decays. Assuming that doubly charged Higgs bosons decay predominantly into a pair of same sign charged leptons through the process $p p \\rightarrow H_{1/2}^{\\pm \\...
Christensen, Neil; Su, Shufang
2012-01-01
The recent results on Higgs boson searches from LHC experiments provide significant guidance in exploring the Minimal Supersymmetric (SUSY) Standard Model (MSSM) Higgs sector. If we accept the existence of a SM-like Higgs boson in the mass window of 123 GeV-127 GeV as indicated by the observed gamma,gamma events, there are two distinct mass regions (in mA) left in the MSSM Higgs sector: (a) the lighter CP-even Higgs boson being SM-like and the non-SM-like Higgs bosons all heavy and nearly degenerate above 300 GeV (an extended decoupling region); (b) the heavier CP-even Higgs boson being SM-like and the neutral non-SM-like Higgs bosons all nearly degenerate around 100 GeV (a small non-decoupling region). On the other hand, due to the strong correlation between the Higgs decays to W+W- and to gamma,gamma predicted in the MSSM, the apparent absence of a W+W- final state signal is in direct conflict with the gamma,gamma peak. If the deficit in the W+W- channel persists, it would imply that the SM-like Higgs boson...
Direct search for Higgs boson in LHCb
Currat, C
2001-01-01
The LHCb detector is a forward one-arm spectrometer to precision measurements of CP violation in the B-meson systems. The motivation of the present work is to assess the potential of LHCb to observe a Standard Model (SM) Higgs signal. The recent results obtained at LEP give a hint of a SM Higgs boson with a mass mH = 115.0 +1.3 –0.9 GeV/c2 with a statistical significance of 2.9 standard deviations. Because of the high longitudinal boost encountered by the products in the pp collisions at LHC, a significant fraction (~30%) of light Higgs (mH = 115 GeV/c2) are produced in the LHCb acceptance 1.8 < h < 4.9. These facts potentially place LHCb in the race for the observation of the SM Higgs. Given a relatively low running luminosity of 2 x 1032 cm-2s-1- compared to the nominal 1034 cm-2s-1 at LHC and a limited geometrical acceptance, we have shown that the channels accessible to LHCb are H + WÂ± Z0 b`b + lÂ± X for Higgs masses in the range 100-130 GeV/c2. This work pioneered a setup for the pro...
Daphney Bucher, Thifhelimbilu
2015-10-01
François Englert shared the 2013 Nobel Prize in Physics with Peter Higgs for the theoretical discovery of a mechanism that gives mass to subatomic particles. For this work, he collaborated with Robert Brout, who died in 2011. He looks back on his contribution to science with Thifhelimbilu Daphney Bucher.
Composite Weak Bosons at the Large Hadronic Collider
Fritzsch, Harald
2016-01-01
In a composite model of the weak bosons the p-wave bosons are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be an excited weak tensor boson.
Search for a Higgs Boson Decaying to Weak Boson Pairs at LEP
Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hakobyan, R S; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Nowak, H; Ofierzynski, R A; Organtini, G; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofiev, D O; Prokofev, D; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Roux, B; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Sanders, M P; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M
2003-01-01
A Higgs particle produced in association with a Z boson and decaying into weak boson pairs is searched for in 336.4 1/pb of data collected by the L3 experiment at LEP at centre-of-mass energies from 200 to 209 GeV. Limits on the branching fraction of the Higgs boson decay into two weak bosons as a function of the Higgs mass are derived. These results are combined with the L3 search for a Higgs boson decaying to photon pairs. A Higgs produced with a Standard Model e+e- --> Zh cross section and decaying only into electroweak boson pairs is excluded at 95% CL for a mass below 107 GeV.
Bosonic string theory with dust
International Nuclear Information System (INIS)
We study a modified bosonic string theory that has a pressureless ‘dust’ field on the string worldsheet. The dust is a real scalar field with unit gradient which breaks conformal invariance. Hamiltonian analysis reveals a time reparametrization constraint linear in the dust field momentum and a spatial diffeomorphism constraint. This feature provides a natural ‘dust time’ gauge in analogy with the parametrized particle. In this gauge we give a Fock quantization of the theory, which is complete and self-consistent in d < 26. The Hamiltonian of the theory is not a constraint; as a consequence the Hilbert space and mass spectrum are characterized by an additional parameter, and includes the usual string spectrum as a special case. The other sectors provide new particle spectra, some of which do not have tachyons. (paper)
Leptogenesis and neutral gauge bosons
Heeck, Julian
2016-01-01
We consider low-scale leptogenesis via right-handed neutrinos $N$ coupled to a $Z'$ boson, with gauged $U(1)_{B-L}$ as a simple realization. Keeping the neutrinos sufficiently out of equilibrium puts strong bounds on the $Z'$ coupling strength and mass, our focus being on light $Z'$ and $N$, testable in the near future by SHiP, HPS, Belle II, and at the LHC. We show that leptogenesis could be robustly falsified in a large region of parameter space by the double observation of $Z'$ and $N$, e.g. in the channel $pp\\to Z' \\to NN$ with displaced $N$-decay vertex, and by several experiments searching for light $Z'$, according to the mass of $N$.
Bentivegna, Marco; Spagnolo, Nicolò; Sciarrino, Fabio
2016-04-01
Is it possible to assess the correct functioning of a quantum device which eludes efficient computation of the expected results? The BosonSampling protocol is one of the best candidates to experimentally demonstrate the superior computational power of quantum mechanics, but the problem of its results certification requires the development of new methodologies, when the size of the problem becomes too large for a complete classical simulation. A recent work (Walschaers et al 2016 New J. Phys. 18 032001) has provided a significant step forward in this direction, by developing a statistical test to identify particle types in a many-body interference pattern. This tool can be applied in a general scenario to assess and investigate multi-particle coherent dynamics.
Vector Boson Scattering at ATLAS
Ozcan, V E
2009-01-01
While the Higgs model is the best studied scenario of electroweak symmetry breaking, there is no fundamental reason for the physics responsible for the symmetry breaking to be weakly-coupled. Many alternatives exist, predicting highly model-dependent signatures. By measuring the cross-section for the W and Z scattering at the LHC, it will be possible to obtain model-independent evidence for strong symmetry breaking or to constrain these various models. ATLAS Collaboration has recently performed a realistic simulation of this process and its backgrounds, which takes into account the detector effects and has developed new jet-analysis techniques for identifying vector bosons within the immense QCD backgrounds expected at the LHC. These techniques and the prospects for measuring the scattering signal will be presented.
Weak gauge boson radiation in parton showers
International Nuclear Information System (INIS)
The emission of W and Z gauge bosons off quarks is included in a traditional QCD + QED shower. The unitarity of the shower algorithm links the real radiation of the weak gauge bosons to the negative weak virtual corrections. The shower evolution process leads to a competition between QCD, QED and weak radiation, and allows for W and Z boson production inside jets. Various effects on LHC physics are studied, both at low and high transverse momenta, and effects at higher-energy hadron colliders are outlined
Masses of Higgs bosons in supersymmetric theories
International Nuclear Information System (INIS)
A simple method for Higgs boson mass calculation in the MSSM and in its minimal extension, the so-called next-to-minimal supersymmetric standard model (NMSSM), is suggested. The approach is based on the hierarchic structure of the mass matrix. Such matrices are obtained within the framework of MSSM and NMSSM. The simple analytical expression for Higgs boson spectrum in both these models are obtained. It was shown that the mass of the lightest Higgs boson in the NMSSM can be essentially lighter than its upper bound
Improved effective vector boson approximation revisited
Bernreuther, Werner
2015-01-01
We reexamine the improved effective vector boson approximation which is based on two-vector-boson luminosities $\\mathrm{\\mathbf{L}}_{\\rm pol}$ for the computation of weak gauge-boson hard scattering subprocesses $V_1 V_2\\to {\\cal W}$ in high-energy hadron-hadron or $e^-e^+$ collisions. We calculate these luminosities for the nine combinations of the transverse and longitudinal polarizations of $V_1$ and $V_2$. The quality of this approach is investigated for the reactions $e^-e^+ \\to W^- W^+ \
Bosonic thermoelectric transport and breakdown of universality
International Nuclear Information System (INIS)
We discuss the general principles of transport in normal phase atomic gases, comparing Bose and Fermi systems. Our study shows that two-dimensional bosonic transport is non-universal with respect to different dissipation mechanisms. Near the superfluid transition temperature Tc, a striking similarity between the fermionic and bosonic transport emerges because super-conducting (fluid) fluctuation transport for Fermi gases is dominated by the bosonic, Cooper pair component. As in fluctuation theory, one finds that the Seebeck coefficient changes sign at Tc and the Lorenz number approaches zero at Tc. Our findings appear quantitatively consistent with recent Bose gas experiments. (paper)
An enigma called the Higgs boson
International Nuclear Information System (INIS)
The search for the Higgs boson, the missing pillar of the currently prevailing theory of weak and electromagnetic interactions, is a prime goal of the Large Hadron Collider (LHC) experiment. We review the circumstances, based on which our expectation of the existence of the Higgs boson has grown, how it is expected to be seen at the LHC, and where we stand in the drop of the presently available data. Moreover, we touch upon the fact that the very existence of the Higgs boson as an elementary particle provides a strong hint on possible new laws of physics. (author)
Mapping the genuine bosonic quartic couplings
Eboli, O J P
2016-01-01
The larger center-of-mass energy of the Large Hadron Collider Run 2 opens up the possibility of a more detailed study of the quartic vertices of the electroweak gauge bosons. Our goal in this work is to classify all operators possessing quartic interactions among the electroweak gauge bosons that do not exhibit triple gauge-boson vertices associated to them. We obtain all relevant operators in the non-linear and linear realizations of the $SU(2)_L \\otimes U(1)_Y$ gauge symmetry.
The Goldstone boson equivalence theorem with fermions
Durand, Loyal; Riesselmann, Kurt
1995-01-01
The calculation of the leading electroweak corrections to physical transition matrix elements in powers of $M_H^2/v^2$ can be greatly simplified in the limit $M_H^2\\gg M_W^2,\\, M_Z^2$ through the use of the Goldstone boson equivalence theorem. This theorem allows the vector bosons $W^\\pm$ and $Z$ to be replaced by the associated scalar Goldstone bosons $w^\\pm$, $z$ which appear in the symmetry breaking sector of the Standard Model in the limit of vanishing gauge couplings. In the present pape...
International Nuclear Information System (INIS)
This thesis presents three years of work with the CMS experiment, in the context of the first LHC collisions. Electron objects were studied in particular, as major tools for multi-lepton analyses, in particular the H → ZZ(*) → 4l analysis. During the first months of collisions, we took part in the validation of data registered by the electromagnetic calorimeter. We also measured the efficiency of the level-1 electron and photon trigger during the whole 2010 year. The plateau efficiency is of 99.6% (resp. 98.5 %) on electrons in the barrel part (resp. in the end cap part) of the calorimeter. In order to optimize the discovery potential, we built a new electron charge measurement algorithm. In CMS, this measurement is affected by the large amount of material present in the inner tracker. The performance of this algorithm was measured on 2010 data, for electrons from Z boson decay passing a standard selection. The probability of charge mis-identification is of 1.06% (0.19% with a specific selection), in agreement with the simulation. The physics analysis that was built during this PhD searches doubly charged Higgs bosons decaying into lepton pairs. For the amount of data registered in 2010, one background event is expected to pass the selection, while the amount of signal events depends on the mass hypothesis and on the model. One event was found on data, in agreement with the background expectation, hence the signal was excluded on larger mass ranges than previous experiments: a mass limit was set between 122 GeV/c2 and 176 GeV/c2, depending on the model. (author)
Searches for heavy Higgs bosons decaying to light Higgs bosons with a mass of 125 GeV
Lane, Rebecca
2015-01-01
Searches for Higgs bosons decaying to a pair of Higgs bosons (hh or hA) or for a Higgs boson decaying to Zh/ZA are presented. Different analyses involving Higgs boson decays into bottom-quarks, tau pairs, and diphotons will be summarized in this talk.
International Nuclear Information System (INIS)
The most promising channels for an intermediate mass Higgs boson discovery at LHC are leptonic and photonic decays. Therefore, a good uniformity of response of the electromagnetic calorimeter is required to reach the 0.7% constant term needed. This thesis deals with the absolute calibration of this detector. An electrical description of the calibration system, the detector and its read-out chain has been made for a better comprehension of the signal pulse shapes. A method, using a convolution of the calibration waveforms, has been developed to predict physics response, leading to absolute calibration. The level of accuracy obtained allows to reach the 0.3% contribution to the constant term required. Test beam analysis of a prototype module showed the performance of the electromagnetic calorimeter in terms of local resolution and linearity. A uniformity study has been made, leading to a 0.8% dispersion on a Δη x Δφ = 1.2 x 0.75 area. In a second part, the observability of an invisible Higgs boson produced via weak boson fusion at the LHC is presented. A level 1 trigger strategy for this purely jet and missing ET final states is discussed. A method to measure the level of background using physics events is presented. This analysis shows that an invisible branching ratio of 25% could be reached at 95% CL with only 30 fb-1 for a Higgs boson mass of 120 GeV/c2. (author)
Search for the SM Higgs Boson in the Channel $WH \\to l\
Will, Jonas Zacharias
One of the most important scientific challenges of ATLAS and CMS, multi-purpose de- tectors at CERN’s Large Hadron Collider (LHC), is the discovery or exclusion of the longly sought standard model Higgs boson predicted almost fifty years ago. In summer 2012, both ATLAS and CMS discovered a new particle. Its mass is determined to be 126 . 0 ± 0 . 4 (stat) ± 0 . 4 (sys) GeV (ATLAS) and 125 . 3 ± 0 . 4 (stat) ± 0 . 5 (sys) GeV (CMS) [ 1 , 2 ]. Its further properties are so far consistent with the predicted properties of a standard model Higgs boson within large uncertainties. Besides the Higgs search in the sensitive bosonic channels, H → γγ , H → ZZ , and H → WW , the fermionic channels H → ττ and H → b b contributed to the exclusion of a standard model Higgs boson below the observed excess and are essential for measuring the couplings of the new particle to fermions. In the analysis presented here, the associated Higgs production WH in the Higgs decay channel H → b b is studied on the co...
Higgs Spin Determination and Unitarity of Vector-boson Scattering at the LHC
Frank, Jessica
After the discovery of a new particle at the Large Hadron Collider (LHC), it is crucial to definitely verify or disprove whether this new 125 − 126 GeV resonance is the Higgs boson of the Standard Model (SM). Thus, its features, including its spin, have to be determined. In order to distinguish the two most likely spin hypotheses, spin-0 or spin-2, the phenomenology of light spin-2 resonances produced in different gluon-fusion and vectorboson-fusion processes at the LHC is studied. Starting from an effective model for the interaction of a spin-2 particle with SM gauge bosons, cross sections and differential distributions are calculated within the Monte Carlo program Vbfnlo. Whereas with specific model parameters, such a spin-2 resonance can mimic rates and transverse-momentum distributions of a SM Higgs boson in the main decay channels γγ, WW and ZZ, several distributions allow to separate spin-2 from spin-0, almost independently of model parameters. Since the SM Higgs boson ensures the unitarity of the S...
Light NMSSM Higgs boson in SUSY cascade decays at the LHC
International Nuclear Information System (INIS)
An interesting feature of the next-to-minimal supersymmetric standard model (NMSSM) is that one or more Higgs bosons may be comparably light (MHiZ) without being in conflict with current experimental bounds. Due to a large singlet component, their direct production in standard channels at the Large Hadron Collider (LHC) is suppressed. We demonstrate that there are good prospects for observing such a light Higgs boson in decays of heavy neutralinos and charginos. We consider an example scenario with 20 GeVH1Z and show that a large fraction of the cascade decays of gluinos and squarks involves the production of at least one Higgs boson. Performing a Monte Carlo analysis at the level of fast detector simulation, it is demonstrated how the Higgs signal can be separated from the main backgrounds, giving access to the Yukawa coupling of the Higgs to bottom quarks. Analyzing the resulting b anti b mass spectrum could provide an opportunity for light Higgs boson discovery already with 5 fb-1 of LHC data at 7 TeV. (orig.)
Light NMSSM Higgs boson in SUSY cascade decays at the LHC
Energy Technology Data Exchange (ETDEWEB)
Staal, O.; Weiglein, G.
2011-08-15
An interesting feature of the next-to-minimal supersymmetric standard model (NMSSM) is that one or more Higgs bosons may be comparably light (M{sub H{sub i}}
The Constrained NMSSM with a 125 GeV Higgs boson -- A global analysis
Kowalska, Kamila; Roszkowski, Leszek; Sessolo, Enrico Maria; Trojanowski, Sebastian; Tsai, Yue-Lin Sming
2013-01-01
We present the first global analysis of the Constrained NMSSM that investigates the impact of the recent discovery of a 125 GeV Higgs-like boson, of limits on supersymmetry from ~5/fb of data accumulated at the LHC, as well as of other relevant constraints from colliders, flavor physics and dark matter. We consider three possible cases, assuming in turn that the discovered Higgs boson is: i) the lightest Higgs boson of the model; ii) the next-to-lightest Higgs boson; and iii) a combination of both roughly degenerate in mass. The likelihood function for the Higgs signal uses signal rates in the \\gamma\\gamma\\ and ZZ --> 4l channels, while that for the Higgs exclusion limits assumes decay through the \\gamma\\gamma, \\tau\\tau, ZZ and W^+W^- channels. In all cases considered we identify the 68% and 95% credible posterior probability regions in a Bayesian approach. We find that, when the constraints are applied with their respective uncertainties, the first case shows strong CMSSM-like behavior, with the stau coannih...
Searching for a Heavy Higgs boson in a Higgs-portal B-L Model
Banerjee, Shankha; Spannowsky, Michael
2015-01-01
We study the discovery prospects of a heavy neutral scalar arising from a $U(1)_{B-L}$ extension of the Standard Model (SM) during the Large Hadron Collider's high luminosity runs (HL-LHC). This heavy neutral scalar mixes with the SM Higgs boson through a Higgs portal and interacts with the SM particles with an interaction strength proportional to the sine of the mixing angle. The mixing between the two Higgs bosons is constrained by direct and indirect measurements. We choose an experimentally viable mixing angle and explore in detail the $ZZ$ and $WW$ decay modes of the heavy Higgs boson. For the $ZZ$ case, we focus on the cleanest $4\\ell$ and $2\\ell 2j$ final states and find that a heavy Higgs boson of mass smaller than 500 GeV can be discovered at the HL-LHC. For the $WW$ decay mode, we analyze the $\\ell jj \\slashed{E}_T$ signature. We implement novel background reduction techniques in order to tackle the huge background by performing both cut-based and multivariate analyses. However, large backgrounds re...
Four-lepton LHC events from MSSM Higgs boson decays into neutralino and chargino pairs
Bisset, Mike; Kersting, Nick; Moortgat, Filip; Moretti, Stefano
2009-01-01
Heavy neutral Higgs boson production and decay into neutralino and chargino pairs is studied at the Large Hadron Collider in the context of the Minimal Supersymmetric Standard Model. Higgs boson decays into the heavier neutralino and chargino states, i.e., H^0 or A^0 to tilde{chi}_i^0 tilde{chi}_j^0 (i,j = 2,3,4) as well as H^0 or A^0 to tilde{chi}_1^{pm} tilde{chi}_2^{mp}, tilde{chi}_2^+ tilde{chi}_2^- (all leading to four-lepton plus missing transverse energy final states), is found to improve the possibilities of discovering such Higgs states beyond those previously identified by considering H^0 or A^0 to tilde{chi}_2^0 tilde{chi}_2^0 decays only. In particular, H^0,A^0 bosons with quite heavy masses, approaching ~800 GeV in the so-called `decoupling region' where no clear SM signatures for the heavier MSSM Higgs bosons are known to exist, can now be discerned, for suitable but not particularly restrictive configurations of the low energy supersymmetric parameters. The high M_A discovery reach for the H^0 ...
Search for nonminimal neutral Higgs bosons from Z-boson decays
International Nuclear Information System (INIS)
Using the Mark II detector at the SLAC Linear Collider, we search for decays of the Z boson to a pair of nonminimal Higgs bosons (Z→Hs0Hp0), where one of them is relatively light (approx-lt 10 GeV). We find no evidence for these decays and we obtain limits on the ZHs0Hp0 coupling as a function of the Higgs-boson masses
Unveiling the MSSM Neutral Higgs Bosons with Leptons and a Bottom Quark
Altunkaynak, Baris; Yang, Kesheng
2013-01-01
We investigate the prospects for the discovery of neutral Higgs bosons produced with a bottom quark where the Higgs decays into a pair of tau leptons and the taus decay into an electron-muon pair, i.e. $bg \\to b\\phi^0 \\to b\\tau^+\\tau^- \\to be^\\pm\\mu^\\mp + E\\!\\!\\!/_T$, $\\phi^0 = h^0, H^0, A^0$. Our study has been done within the framework of the Minimal Supersymmetric Standard Model. We consider the dominant physics backgrounds including the production of Drell-Yan processes ($b\\tau^+\\tau^-$ and $j\\tau^+\\tau^-, j = q, g$), top quark pair ($t\\bar{t}$), $tW$ and $jWW$ with realistic acceptance cuts and efficiencies. We present $5\\sigma$ discovery contours for the neutral Higgs bosons in the ($M_A,\\tan\\beta$) plane as well as the region with a favored light Higgs mass (123 GeV $\\le m_h\\le$ 129 GeV). Promising results are found for the CP-odd pseudoscalar ($A^0$) and the heavier CP-even scalar ($H^0$) Higgs bosons with masses up to 800 GeV and $\\tan\\beta \\simeq 50$ at the LHC with a center of mass energy ($\\sqrt{s...
LHC signals of a B -L supersymmetric standard model C P -even Higgs boson
Hammad, A.; Khalil, S.; Moretti, S.
2016-06-01
We study the scope of the Large Hadron Collider in accessing a neutral Higgs boson of the B -L supersymmetric standard model. After assessing the surviving parameter space configurations following the Run 1 data taking, we investigate the possibilities of detecting this object during Run 2. For the model configurations in which the mixing between such a state and the discovered standard-model-like Higgs boson is non-negligible, there exist several channels enabling its discovery over a mass range spanning from ≈140 to ≈500 GeV . For a heavier Higgs state, with mass above 250 GeV (i.e., twice the mass of the Higgs state discovered in 2012), the hallmark signature is its decay in two such 125 GeV scalars, h'→h h , where h h →b b ¯ γ γ . For a lighter Higgs state, with mass of order 140 GeV, three channels are accessible: γ γ , Z γ , and Z Z , wherein the Z boson decays leptonically. In all such cases, significances above discovery can occur for already planned luminosities at the CERN machine.
Research on Higgs bosons by positron-electron collisions
International Nuclear Information System (INIS)
The experimental results obtained at LEP concerning Higgs bosons research are discussed. The existence of the Higgs bosons, from the Standard Model principles, is reviewed. The investigations on charged and neutral Higgs bosons are discussed taking into account a two-doublets model. The investigations show: that the Higgs bosons cannot be found between zero and 41 GeV, and that the Higgs boson mass is approximately 40 GeV
From the Higgs boson to the search for new physics: the prospects for the LHC programme at CERN
CERN. Geneva
2013-01-01
The discovery of the Higgs boson, which was the subject of this year's Nobel prize for physics, has brought us the missing piece of the Standard Model of Particle Physics. However, many observations (such as the predominance of matter over antimatter in the Universe, the existence of dark matter observed by the cosmologists and even the fact that the Higgs boson has a relatively small mass) underline that our knowledge of the structure of matter and its interactions is incomplete. A wide-ranging programme of research spanning several decades to come thus awaits us at the LHC. Philippe Bloch will begin his lecture by giving us the latest news on the Higgs boson, and will then go on to explain how developments at the LHC and its experiments, which will resume in 2015, will explore these fund...
Kooren Joel A; Rhodus Nelson L; Tang Chuanning; Jagtap Pratik D; Horrigan Bryan J; Griffin Timothy J
2011-01-01
Abstract Introduction Early diagnosis of Oral Squamous Cell Carcinoma (OSCC) increases the survival rate of oral cancer. For early diagnosis, molecular biomarkers contained in samples collected non-invasively and directly from at-risk oral premalignant lesions (OPMLs) would be ideal. Methods In this pilot study we evaluated the potential of a novel method using commercial PerioPaper absorbent strips for non-invasive collection of oral lesion exudate material coupled with mass spectrometry-bas...
Weak boson production via vector-boson fusion rate at NLO matched with Powheg
International Nuclear Information System (INIS)
The production of weak vector-bosons in association with two jets is an important background to Higgs-boson searches in vector-Boson fusion (VBF) at the LHC. In order to make reliable predictions, the combination of fixed-order NLO-calculations and parton-showers is indispensable. We present the implementation of the weak boson production via VBF in the Powheg-Box. This is a first step to interface Vbfnlo, a fully flexible Monte Carlo program, with the Powheg-Box.
Landau-Yang Theorem and Decays of a Z' Boson into Two Z Bosons
Keung, Wai-Yee; Low, Ian; Shu, Jing
2008-01-01
We study the decay of a Z' boson into two Z bosons by extending the Landau-Yang theorem to a parent particle decaying into two Z bosons. For a spin-1 parent the theorem predicts: 1) there are only two possible couplings and 2) the normalized differential cross-section depends on kinematics only through a phase shift in the azimuthal angle between the two decay planes of the Z boson. When the parent is a Z' the two possible couplings are anomaly-induced and CP-violating, respectively. At the L...
Bosonic superconformal Toda model and dressing transformation
International Nuclear Information System (INIS)
The authors show the dressing transformations of the basic field and the classical chiral operators in the Bosonic Superconformal Toda model. After quantization, The related quantum algebra is obtained
A Historical Profile of the Higgs Boson
Energy Technology Data Exchange (ETDEWEB)
Ellis, John; Gaillard, Mary K.; Nanopoulos, Dimitri V.
2012-01-31
The Higgs boson was postulated in 1964, and phenomenological studies of its possible production and decays started in the early 1970s, followed by studies of its possible productionin e{sup +} e{sup -}, {anti p}p and pp collisions, in particular. Until recently, the most sensitive searches for the Higgs boson were at LEP between 1989 and 2000, which have been complemented bysearches at the Fermilab Tevatron. The LHC has recently entered the hunt, excluding a Higgs boson over a large range of masses and revealing a tantalizing hint in the range 119 to125 GeV, and there are good prospects that the existence or otherwise of the Higgs boson will soon be established. One of the most attractive possibilities is that the Higgs bosonis accompanied by supersymmetry, though composite options have yet to be excluded. This article reviews some of the key historical developments in Higgs physics over the past half-century.
Quantum geometry of bosonic strings - revisited
International Nuclear Information System (INIS)
We review the original paper by A.M. Polyakov (Quantum Geometry of Bosonic Strings) with corrections and improvements the concepts exposed there and following as closely as possible to the original A.M. Polyakov's paper. (author)
Boson representation of the asymmetric rotator
International Nuclear Information System (INIS)
The yrast states, as well as the wobbling frequency are analyzed using alternatively the Holstein-Primakoff and Dyson boson expansions. Both the prolate and oblate shapes are treated using Oz as quantization axis. (author)