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An evolutionary analysis of economic hubs and transmission mechanisms for wastewater discharge

Li, XuefengSubjects: Management Science >> Other Disciplines of Management Science

Due to the destruction of aquatic ecology and pollution of the water environment, policy formulation needs to pay more attention to factors other than economic benefits. Past research mainly relied on the average propagation lengths (APL) of wastewater discharge to empirically analyze the wastewater propagation between sectors. The hub sectors of wastewater discharge, which are densely-connected to other sectors, play key roles in reflecting wastewater discharge or wastewater treatment in the overall economic system. However, there is current ambiguity deficiency in analytic results of economic hubs and transmission mechanisms of wastewater discharge. At the same time, analyzing the transmission mechanism of wastewater discharge, proposing wastewater management and containment strategies are essential to sustainable development of water resource. This paper calculates the wastewater discharge APL based on the compiled sequential water input-occupancy-output tables of 49 sectors for 2002, 2007, 2012 and 2017 in China. Then, we introduce more broadly marginal dependence linkages into APL. A coupled model named APL-HCG (APL with hub covariance graph) is proposed to analyze the hub wastewater discharge sectors and hub propagation chains overall. The results illustrate the evolutionary pattern of the hub sectors of wastewater discharge and the transmission mechanism implicit in the key wastewater propagation chains nationwide from 2002 to 2017. |

submitted time
2021-01-18
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Realistic Flipped SU(5) from Orbifold SO(10)

Balazs,C; Kang,Z; Li,T; Wang,F; Yang,JMSubjects:

We propose a realistic flipped SU(5) model derived from a five-dimensional orbifold SO(10) model. The Standard Model (SM) fermion masses and mixings are explained by combining the traditional Froggatt-Nielsen mechanism with the five-dimensional wave funct |

submitted time
2016-12-28
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Realistic Flipped SU(5) from Orbifold SO(10)

Balazs,C; Kang,Z; Li,T; Wang,F; Yang,JMSubjects:

We propose a realistic flipped SU(5) model derived from a five-dimensional orbifold SO(10) model. The Standard Model (SM) fermion masses and mixings are explained by combining the traditional Froggatt-Nielsen mechanism with the five-dimensional wave funct |

submitted time
2016-12-28
Hits*1865*，
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Efficient numerical evaluation of Feynman integrals

Zhao Li; Jian Wang; Qi-Shu Yan; Xiaoran ZhaoSubjects: Physics >> Nuclear Physics

Feynman loop integrals are a key ingredient for the calculation of higher order radiation effects, and are responsible for reliable and accurate theoretical prediction. We improve the efficiency of numerical integration in sector decomposition by implementing a quasi-Monte Carlo method associated with the CUDA/GPU technique. For demonstration we present the results of several Feynman integrals up to two loops in both Euclidean and physical kinematic regions in comparison with those obtained from FIESTA3. It is shown that both planar and non-planar two-loop master integrals in the physical kinematic region can be evaluated in less than half a minute with?O(10?3)accuracy, which makes the direct numerical approach viable for precise investigation of higher order effects in multi-loop processes, e.g. the next-to-leading order QCD effect in Higgs pair production via gluon fusion with a finite top quark mass. |

Landau-Yang theorem and decays of a Z ' boson into two Z bosons

Keung, Wai-Yee; Low, Ian; Shu, JingSubjects: Physics >> The Physics of Elementary Particles and Fields

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. |

submitted time
2016-07-11
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Higgs mechanism and loop-induced decays of a scalar into two Z bosons

Cao, Qing-Hong; Jackson, C. B.; Keung, Wai-Yee; Low, Ian; Shu, JingSubjects: Physics >> The Physics of Elementary Particles and Fields

We discuss general on-shell couplings of a scalar with two Z bosons using an operator analysis. In addition to the operator that originated from the Higgs mechanism, two dimension-five operators, one CP even and one CP odd, are generated only at the loop level. Simple formulas are derived for the differential decay distributions when the Z pair subsequently decays into four leptons by computing the helicity amplitudes, from which it is shown the CP-odd operator merely induces a phase shift in the azimuthal angular distribution between the two decay planes of the Z bosons. We also investigate new physics scenarios giving rise to loop-induced decays of a scalar into the ZZ pair, and argue that the total decay width of such a scalar would be an order-of-magnitude smaller than that of a Higgs boson, should such decays be observed in the early running of the LHC. Therefore, the total decay width alone is a strong indicator of the Higgs nature, or the lack thereof, of a scalar resonance in ZZ final states. In addition, we study the possibility of using the azimuthal angular distribution to disentangle effects among all three operators. |

submitted time
2016-07-08
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Dimension-six CP-violating operators of the third-family quarks and their effects at colliders

Yang, JM; Young, BLSubjects: Physics >> The Physics of Elementary Particles and Fields

We list all possible dimension-six CP-violating SUc(3) x SUL(2) x U-Y(1)-invariant operators involving the third-family quarks, which can be generated by new physics at a higher energy scale. The expressions of these operators after electroweak symmetry breaking and the induced effective couplings Wt (b) over bar,Xb (b) over bar, and Xt (t) over bar (X = Z,gamma,g,H) are also presented. We evaluate sample contributions of these operators to CP-odd asymmetries of transverse polarization of the top quark in single top quark production at the upgraded Fermilab Tevatron, the same polarization effect in top-quark-top-antiquark pair production at the NLC, and the CP-odd observables of momentum correlations among the top quark decay products at the NLC. The energy and luminosity sensitivity in probing this CP-violating new physics is also studied. |

Subjects: Physics >> The Physics of Elementary Particles and Fields

If the sparticles are relatively heavy (a few TeV) while the Higgs sector is not so heavy (m(A) is not so large), the Higgs boson Yukawa couplings can harbor sizable quantum effects of sparticles and these large residual effects may play a special role in probing supersymmetry at foreseeable colliders. In this work, focusing on the supersymmetric QCD effects in the hb (b) over bar coupling (h is the lightest CP-even Higgs boson), we give a comparative study for the two popular supersymmetric models: the MSSM and NMSSM. While for both models the supersymmetric QCD can leave over large residual quantum effects in hb (b) over bar coupling, the NMSSM can allow for a much broader region of such effects. Since these residual effects can be over 20% for the hb (b) over bar coupling (and thus over 40% for the ratio Br(h -> b (b) over bar)/Br(h -> tau(+)tau(-))), future measurements may unravel the effects of heavy sparticles or even distinguish the two models. (C) 2009 Elsevier B.V. All rights reserved. |

Subjects: Physics >> The Physics of Elementary Particles and Fields

Inspired by the recent LHC Higgs data and null search results of supersymmetry (SUSY), we scan the parameter space of the Minimal Supersymmetric Standard Model (MSSM) with relatively heavy sparticles (1-3 TeV). Then in the parameter space allowed by current collider experiments and dark matter detections, we calculate the complete one) SUSY QCD corrections to pp -> b (b) over barh at the LHC with root s = 14 TeV and obtain the following observations: (1) For the large values of tan beta and low values of m(A), the SUSY QCD effects can be quite large, which, however, have been excluded by the latest results of LHC search for H/A -> tau(+)tau(-); (ii) For modest values of tan beta and m(A) which so far survived all experimental constraints, the SUSY QCD corrections can maximally reach about -9%. |

Higgs boson mass in NMSSM with right-handed neutrino

Wang, Wenyu; Yang, Jin Min; You, Lin LinSubjects: Physics >> The Physics of Elementary Particles and Fields

In order to have massive neutrinos, the right-handed neutrino/sneutrino superfield (N) need to be introduced in supersymmetry. In the framework of NMSSM (the MSSM with a singlet S) such an extension will dynamically lead to a TeNT-scale Majorana mass for the right-handed neutrino through the S N N coupling when S develops a vev (the free Majorana mass term is forbidden by the assumed Z(3) symmetry). Also, through the couplings S N N and SHuHd the SM-like Higgs boson (a mixture of H-u, H-d and S) can naturally couple with the right-handed neutrino/sneutrino. As a result, the TeV-scale right-handed neutrino/sneutrino may significantly contribute to the Higgs boson mass. Through an explicit calculation, we find that the Higgs boson mass can indeed be sizably altered by the right-handed neutrino/sneutrino. Such new contribution can help to push up the SM-like Higgs boson mass and thus make the NMSSM more natural. |