相关论文: Standard Model Higher Order Corrections to the WW\…
Grinstein, O'Connell and Wise have recently presented an extension of the Standard Model (SM), based on the ideas of Lee and Wick (LW), which demonstrates an interesting way to remove the quadratically divergent contributions to the Higgs…
It is shown how the S-matrix pinch technique may be extended to the cases of external scalar and gauge boson fields. Using this extension, the universality of the pinch technique gauge-independent one-loop gauge boson self-energy in a…
We evaluate at one loop the self-energies in generic D dimensions for the W,Z mesons in the Electroweak model where the gauge group is nonlinearly realized. In this model the Higgs boson parameters are absent, while a second mass parameter…
Motivated by the possibility of experimental determination of top quark form factors in upcoming e+ e- experiments, as recently discussed by Atwood and Soni, we show at the one loop level that the conventionally defined magnetic dipole…
We consider a class of sigma models that appears from a generalisation of the gauged WZW model parametrised by a constant matrix $Q$. Particular values of $Q$ correspond to the standard gauged WZW models, chiral gauged WZW models and a…
The invariance of extensions of the Standard Model under the full SU(3)XSU(2)XU(1) gauge group can be used to classify general vector bosons and to write their interactions in a model-independent fashion. This description is useful for both…
The standard model $SU(2)_L\times U(1)_Y$ gauging of the Wess-Zumino-Witten term requires a modified counterterm when background fields, needed to generate the full set of currents, are introduced. The modified counterterm plays an…
We review the role of the Higgs boson in preserving unitarity of the scattering amplitudes in the Standard Model (SM). We will look at the processes $\nu_e + \bar{\nu}_e \rightarrow W^-_L +W^+_L $, $ W^-_L + W^+_L \rightarrow W^-_L +W^+_L $…
Following the thread of R. Gastmans, S. L. Wu and T. T. Wu, the calculation in the unitary gauge for the $H \to \gamma \gamma$ process via one W loop is repeated, but without the specific choice of the independent loop momentum for the…
A summary of recent results obtained for higher-order corrections to precision observables in the Standard Model and the Minimal Supersymmetric Standard Model is given. In the Standard Model electroweak two-loop results valid for arbitrary…
We study QED corrections to operator matrix elements involving heavy composite particles (e.g., heavy-mesons, nuclei, and atoms). We define a new notion of reducible and irreducible graphs which is useful for systems with many discrete…
Using local gauge invariance in the form of the Ward-Takahashi identity and the fact that properly constructed current operators must be free of kinematic singularities, it is shown that the magnetic moment $\mu$ and the quadrupole moment…
Precision experiments, such as those performed at LEP and SLC, offer us an excellent opportunity to constrain extended gauge model parameters. To this end, it is often assumed, that in order to obtain more reliable estimates, one should…
The BRS invariance of the electroweak gauge theory leads to relationships between amplitudes with external massive gauge bosons and amplitudes where some of these gauge bosons are replaced with their corresponding Nambu-Goldstone bosons.…
The Global Color-symmetry Model of QCD is extended to deal with a background electromagnetic field and the associated conserved current is identified for composite $\bar{q}q$ pion modes of the model. Although the analysis is limited to tree…
Low energy effects of generic extensions of the Standard Model can be comprehensively parametrized in terms of higher dimensional effective operators. After the success of all the recent precission tests on the Standard Model, we argue that…
For gauge theory, the matrix element for any physical process is independent of the gauge used. Since this is a formal statement and examples are known where gauge invariance is violated, for any specific process this gauge invariance needs…
We systematically analyze the anomalous dipole $\Delta k_{\gamma}$ and quadrupole $\Delta Q_{\gamma}$ moments of the W gauge bosons in the context of the minimal supersymmetric standard model as functions of the soft SUSY breaking…
Non-decoupling effects of heavy particles present in beyond-the-standard models are studied for the triple gauge boson vertices $\gamma W^+W^-$ and $Z^0W^+W^-$. We show from a general argument that the non-decoupling effects are described…
A systematic method is given for obtaining consistent approximations to the Schwinger-Dyson(SD) and Bethe-Salpeter(BS) equations which maintain the external gauge invariance. We show that for any order of approximation to the SD equation…