共查询到20条相似文献,搜索用时 15 毫秒
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安芬芬 白羽 陈春晖 陈新 陈振兴 Joao Guimaraes da Costa 崔振崴 方亚泉 付成栋 高俊 高艳彦 高原宁 葛韶锋 顾嘉荫 郭方毅 郭军 韩涛 韩爽 何红建 何显柯 何小刚 胡继峰 徐士杰 金山 荆茂强 Susmita Jyotishmati Ryuta Kiuchi 郭家铭 赖培筑 李博扬 李聪乔 李刚 李海峰 李亮 李数 李通 李强 梁浩 梁志均 廖立波 刘波 刘建北 刘涛 刘真 娄辛丑 马连良 Bruce Mellado 莫欣 Mila Pandurovic 钱剑明 钱卓妮 Nikolaos Rompotis 阮曼奇 Alex Schuy 单连友 史静远 史欣 苏淑芳 王大勇 王锦 王连涛 王贻芳 魏彧骞 许悦 杨海军 杨迎 姚为民 于丹 张凯栗 张照茹 赵明锐 赵祥虎 周宁 《中国物理C(英文版)》2019,(4)
The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics.The Higgs boson will be the subject of extensive studies of the ongoing LHC program.At the same time,lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC,with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs boson.The Circular Electron Positron Collider(CEPC)is one of such proposed Higgs factories.The CEPC is an e~+e~- circular collider proposed by and to be hosted in China.Located in a tunnel of approximately 100 km in circumference,it will operate at a center-of-mass energy of 240 GeV as the Higgs factory.In this paper,we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements. 相似文献
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The recent LHC indications of a SM-like Higgs boson near 125 GeV are consistent not only with the Standard Model (SM) but also with Supersymmetry (SUSY). However naturalness arguments disfavour the Minimal Supersymmetric Standard Model (MSSM). We consider the Next-to-Minimal Supersymmetric Standard Model (NMSSM) with a SM-like Higgs boson near 125 GeV involving relatively light stops and gluinos below 1 TeV in order to satisfy naturalness requirements. We are careful to ensure that the chosen values of couplings do not become non-perturbative below the grand unification (GUT) scale, although we also examine how these limits may be extended by the addition of extra matter to the NMSSM at the two-loop level. We then propose four sets of benchmark points corresponding to the SM-like Higgs boson being the lightest or the second lightest Higgs state in the NMSSM or the NMSSM-with-extra-matter. With the aid of these benchmark points we discuss how the NMSSM Higgs boson near 125 GeV may be distinguished from the SM Higgs boson in future LHC searches. 相似文献
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E. E. Boos V. E. Bunichev I. P. Volobuev 《Journal of Experimental and Theoretical Physics》2017,124(5):722-730
We discuss the impact of the constraints from the measurements of the parameters of the observed 125 GeV Higgs boson and from the unconfirmed 750 GeV diphoton excess in the LHC experiments on the properties of a possible extra scalar boson predicted in various Standard Model extensions. We consider an SM extension based on a stabilized brane-world model, in which the effective low-energy Lagrangian for the scalar degrees of freedom turns out to be very general and, for different values of the model parameters, reproduces the scalar field Lagrangians of various SM extensions by a singlet scalar. It is shown that in the simplest variant of the model, where only the gravitational degrees of freedom propagate in the bulk, the 125 GeV scalar state can be consistently interpreted as a Higgs-dominated state for a rather wide range of the model parameters, whereas the production cross section of a heavier radion-dominated state with mass 750 GeV or more turns out to be too small in the allowed region of the model parameter space for producing the wouldbe diphoton excess. 相似文献
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The Majorana nature of neutrinos may only be experimentally verified via lepton-number violating processes involving charged leptons. We explore the Delta L = 2 like-sign dilepton production at hadron colliders to search for signals of Majorana neutrinos. We find significant sensitivity for resonant production of a Majorana neutrino in the mass range of 10-80 GeV at the current run of the Tevatron with 2 fb(-1) integrated luminosity and in the range of 10-400 GeV at the CERN LHC with 100 fb(-1). 相似文献
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In light of the recently obtained LHC Higgs data, we examine the parameter space of the type II twoHiggs-doublet model, in which the 125 GeV Higgs bosons exhibit wrong sign Yukawa couplings. Combining the relevant theoretical and experimental limits, we find that the LHC Higgs data exclude most of the parameter space of the wrong sign Yukawa coupling. For m_H 600 GeV, the allowed samples are mainly distributed across several corners and narrow bands of m_A 20 GeV, 30 m_A 120 GeV, 240 GeV m_A 300 GeV, 380 GeV m_A 430 GeV, and480 GeV m_A 550 GeV. For m_A 600 GeV, m_H is required to be lower than 470 GeV. The light pseudo-scalar with a mass of 20 GeV is still permitted in the case of the wrong sign Yukawa coupling of 125 GeV Higgs bosons. 相似文献
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Rohini M Godbole 《Pramana》2006,67(5):835-847
In this talk I discuss some aspects of CP violation (CPV) in supersymmetry (SUSY) as well as in the Higgs sector. Further,
I discuss ways in which these may be probed at hadronic colliders. In particular I will point out the ways in which studies
in the
sector at the Tevatron may be used to provide information on this and how the search can be extended to the LHC. I will then
follow this by a discussion of the CP mixing induced in the Higgs sector due to the above-mentioned CPV in the soft SUSY breaking
parameters and its effects on the Higgs phenomenology at the LHC. I would then point out some interesting aspects of the phenomenology
of a moderately light charged Higgs boson, consistent with the LEP constraints, in this scenario. Decay of such a charged
Higgs boson would also allow a probe of a light (≲50 GeV), CP-violating (CPV) Higgs boson. Such a light neutral Higgs boson
might have escaped detection at LEP and could also be missed at the LHC in the usual search channels. 相似文献
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New physics that exhibits irregular tracks such as kinks, intermittent hits, or decay in flight may easily be missed at hadron colliders. We demonstrate this by studying viable models of light, O(10 GeV), colored particles that decay predominantly inside the tracker. Such particles can be produced at staggering rates, and yet, may not be identified or triggered on at the LHC, unless specifically searched for. In addition, the models we study provide an explanation for the original measurement of the anomalous charged track distribution by CDF. The presence of irregular tracks in these models reconcile that measurement with the subsequent reanalysis and the null results of ATLAS and CMS. Our study clearly illustrates the need for a comprehensive study of irregular tracks at the LHC. 相似文献
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Recent LHC data showed excesses of Higgs-like signals at the Higgs mass of around 125 GeV. This may indicate supersymmetric models with relatively heavy scalar fermions to enhance the Higgs mass. The desired mass spectrum is realized in the anomaly-mediated supersymmetry breaking model, in which the Wino can naturally be the lightest superparticle (LSP). We discuss possibilities for confirming such a scenario, particularly detecting signals from Wino LSP at direct detection experiments, indirect searches at neutrino telescopes and at the LHC. 相似文献
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Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abramowicz H Abreu H Acerbi E Acharya BS Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Akesson TP Akimoto G Akimov AV Akiyama A Alam MS Alam MA Albert J Albrand S Aleksa M Aleksandrov IN Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J Aliyev M Allport PP 《Physical review letters》2012,108(4):041805
A search for new phenomena in tt events with large missing transverse momentum in proton-proton collisions at a center-of-mass energy of 7 TeV is presented. The measurement is based on 1.04 fb(-1) of data collected with the ATLAS detector at the LHC. Contributions to this final state may arise from a number of standard model extensions. The results are interpreted in terms of a model where new top-quark partners are pair produced and each decay to an on-shell top (or antitop) quark and a long-lived undetected neutral particle. The data are found to be consistent with standard model expectations. A limit at 95% confidence level is set excluding a cross section times branching ratio of 1.1 pb for a top-partner mass of 420 GeV and a neutral particle mass less than 10 GeV. In a model of exotic fourth generation quarks, top-partner masses are excluded up to 420 GeV and neutral particle masses up to 140 GeV. 相似文献
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N. Becerici?Schmidt S. A. ?etin S. I?tin S. Sultansoy 《The European Physical Journal C - Particles and Fields》2010,66(1-2):119-126
The impact of the fourth Standard Model family on Higgs boson search at Tevatron and LHC is reviewed. The enhancement due to a fourth SM family in the production of Higgs boson via gluon fusion already enables the Tevatron experiments to become sensitive to Higgs masses between 140 and 200 GeV and could increase this sensitivity up to about 300 GeV until the LHC is in shape. The same effect could enable the LHC running even at 7 TeV center of mass energy to scan Higgs masses between 200 and 300 GeV only with a few hundred pb?1 of integrated luminosity. 相似文献
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Inclusive standard model Higgs boson pair production and subsequent decay to same-sign dileptons via weak gauge W+/- bosons at the CERN Large Hadron Collider (LHC) has the capability to determine the Higgs boson self-coupling, lambda. The large top quark mass limit is found not to be a good approximation for the signal if one wishes to utilize differential distributions in the analysis. We find that it should be possible at the LHC with design luminosity to establish that the standard model Higgs boson has a nonzero self-coupling and that lambda/lambda(SM) can be restricted to a range of 0-3.7 at 95% confidence level if its mass is between 150 and 200 GeV. 相似文献
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Results for the complete NLO electroweak corrections to Standard Model Higgs production via gluon fusion are included in the total cross section for hadronic collisions. Artificially large threshold effects are avoided working in the complex-mass scheme. The numerical impact at LHC (Tevatron) energies is explored for Higgs mass values up to 500 GeV (200 GeV). Assuming a complete factorization of the electroweak corrections, one finds a +5% shift with respect to the NNLO QCD cross section for a Higgs mass of 120 GeV both at the LHC and the Tevatron. Adopting two different factorization schemes for the electroweak effects, an estimate of the corresponding total theoretical uncertainty is computed. 相似文献
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《理论物理通讯》2016,(12)
We calculate the large mass dileptons production from the jet-dilepton conversion in spherical expanding quark-gluon plasma at Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) energies.The jetdilepton production exceeds the thermal and Drell Yan dilepton production in the large mass region of 4.5 GeVM 5.5 GeV and 7 GeV M 9 GeV in central Pb+Pb collisions at SNNS~(1/2)=2.76 TeV and 5.5 TeV,respectively.We present the solution of(1+3)-dimensional fluid hydrodynamics with spherical symmetry.We find that the transverse flow of the QGP leads to a rapid cooling of the fire ball and suppression of the jet-dilepton conversion.The suppression is also evident at intermediate and large mass at LHC energies.The energy loss of the jet-dilepton conversion is concerned. 相似文献
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I. A. Pshenichnov E. V. Karpechev A. B. Kurepin I. N. Mishustin 《Physics of Atomic Nuclei》2011,74(1):139-150
Beam nuclei accelerated at the Large Hadron Collider (LHC) at CERN are lost due to interactions with the counter-rotating
beam, residual gas, and accelerator elements. Proper modelling of the beam transport and radiation load on accelerator components
requires reliable prediction of the yields of nuclear fragments produced in electromagnetic dissociation and hadronic fragmentation
of beam nuclei. We investigate electromagnetic and hadronic fragmentation of lead nuclei in collisions with various nuclei
and single electrons at the injection and collision energies of the LHC. The consideration is based on the RELDIS and abrasion-ablation
models. Since this approach well describes Pb fragmentation data at 30 and 158 A GeV, its validity for Pb nuclei at the LHC collision energy is also expected. 相似文献
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Stoponium, a bound state of the top squark and its antiparticle in a supersymmetric model, may be found in the ongoing Higgs searches at the LHC. Its WW and ZZ detection ratios relative to the standard model Higgs boson can be more than unity from the WW* threshold to the two Higgs threshold. The γγ channel is equally promising. Some regions of the stoponium mass below 150 GeV are already being probed by the ATLAS and CMS experiments. 相似文献
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A. De Roeck V.A. Khoze A.D. Martin R. Orava M.G. Ryskin 《The European Physical Journal C - Particles and Fields》2002,25(3):391-403
We summarize the possible processes which may be used to search for a Higgs boson, of mass in the range 114-130 GeV, at the
LHC. We discuss, in detail, two processes with rapidity gaps: exclusive Higgs production with tagged outgoing protons and
production by Weak Boson Fusion, in each case taking as the signal. We make an extensive study of all possible backgrounds, and discuss the relevant experimental issues. We emphasize the special features of these signals, and of their
background processes, and show that they could play an important role in identifying a light Higgs boson at the LHC.
Received: 5 July 2002 / Published online: 30 August 2002 相似文献
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C. Beskidt W. de Boer D. I. Kazakov F. Ratnikov 《The European Physical Journal C - Particles and Fields》2012,72(10):1-8
The ATLAS and CMS experiments did not find evidence for Supersymmetry using close to 5/fb of published LHC data at a center-of-mass energy of 7 TeV. We combine these LHC data with data on $B^{0}_{s}\to \mu^{+}\mu^{-}$ (LHCb experiment), the relic density (WMAP and other cosmological data) and upper limits on the dark matter scattering cross sections on nuclei (XENON100 data). The excluded regions in the constrained Minimal Supersymmetric SM (CMSSM) lead to gluinos excluded below 1270 GeV and dark matter candidates below 220 GeV for values of the scalar masses (m 0) below 1500 GeV. For large m 0 values the limits of the gluinos and the dark matter candidate are reduced to 970 GeV and 130 GeV, respectively. If a Higgs mass of 125 GeV is imposed in the fit, the preferred SUSY region is above this excluded region, but the size of the preferred region is strongly dependent on the assumed theoretical error. 相似文献
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The Compact Linear Collider(CLIC) is a future e+e- linear collider. The CLIC study concentrated on a design of center-of-mass energy of 3 TeV and demonstrated the feasibility of the technology. However, the physics also demands lower energy collision. To satisfy this, CLIC can be built in stages. The actual stages will depend on LHC results. Some specific scenarios of staged constructions have been shown in CLIC Concept Design Report(CDR). In this paper, we concentrate on the main linac lattice design for Ecm=1 TeV CLIC aiming to upgrade from Ecm=500 GeV CLIC and then to Ecm=3 TeV one. This main linac accelerates the electron or positron beam from9 GeV to 500 GeV. A primary lattice design based on the 3 TeV CLIC main linac design and its optimization based on the beam dynamics study will be presented. As we use the same design principles as 3TeV CLIC main linac, this optimization is basically identical to the 3 TeV one. All the simulations results are obtained using the tracking code PLACET. 相似文献