摘要:

Closed forms are derived for the effective actions for free, massive spinless fields in maximally-symmetric spacetimes in arbitrary dimensions. The results have simple expressions in terms of elementary functions (for odd dimensions) or multiple Gamma functions (for even dimensions). ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57077

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Conformal (Weyl) gravity has been advanced in the recent past as an alternative to General Relativity (GR). The theory has had some success in fitting galactic rotation curves without the need for copious amounts of dark matter. To check the viability of Weyl gravity, we calculate the deflection of light in the exterior of a static spherically symmetric source. The result for the deflection of light is remarkably simple: besides the usual positive (attractive) Einstein deflection of4GM/r0we obtain an extra deflection term of−&ggr;r0where &ggr; is a constant andr0is the radius of closest approach. With a negative &ggr;, the extra term can increase the deflection on large distance scales (galactic or greater) and therefore imitate the effect of dark matter. Notably, the negative sign required for &ggr; is opposite to the sign of &ggr; used to fit galactic rotation curves by Mannheim and Kazanas. We explain why the signs in the two analyses are different. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57069

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Leptoquarks can be produced in substantial numbers for masses very close to the collider center of mass energy ine+e−,e&ggr;,and&mgr;+&mgr;−collisions due to the quark content of the photon resulting in equivalently high discovery limits. Using polarization asymmetries in ane&ggr;collider the ten different types of leptoquarks listed by Buchmu¨ller, Ru¨ckl and Wyler can be distinguished from one another for leptoquark masses essentially up to the kinematic limit. Thus, if a leptoquark were discovered, ane&ggr;collider could play a crucial role in determining its origins. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57078

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

We study the effects of gluon radiation on top production and decay processes at ane+e−collider. The matrix elements are computed without any approximations, using spinor techniques. We use a Monte Carlo event generator which takes into account the infrared singularity due to soft gluons and differences in kinematics associated with radiation in the production versus decay process. The calculation is illustrated for several strategies of top mass reconstruction. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57081

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

TheSU(2Nf)⊗O(3)constituent quark model symmetry of the light diquark system are used to analyze single pion transitions of S-wave to S-wave and P-wave to S-wave heavy baryons. We show that the Heavy Quark Symmetry (HQS) coupling factors are given in terms of the three independent couplingsg&Sgr;Q&Lgr;Q&pgr;,f&Lgr;Q1&Sgr;Q&pgr;andf&Lgr;Q1*&Sgr;Q&pgr;.Light-Front quark model spin wave functions are, then, employed to calculate these couplings and to predict decay rates of single pion transitions between charm baryon states. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57062

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The CP-angles &agr;, &bgr; and &ggr; can be extracted from CP-violating asymmetries in theBsystem, but only up to discrete ambiguities. These discrete ambiguities make it difficult to determine with certainty whether or not new physics is present. I show that, if the condition&agr;+&bgr;+&ggr;=&pgr;is imposed, there remains a twofold ambiguity in the CP-angle set (&agr;,&bgr;,&ggr;), and I discuss ways to cleanly resolve this final discrete ambiguity. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57063

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

We consider the possibility of observing CP violation in quasi-inclusive decays of the typeB−→K−X,B−→K*−X,B¯0→K−XandB¯0→K*−X,whereXdoes not contain strange quarks. We present estimates of rates and asymmetries for these decays in the Standard Model and comment on the experimental feasibility of observing CP violation in these decays at futureBfactories. We find the rate asymmetries can be quite sizeable. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57085

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

One way to detect the presence of physics beyond the Standard Model is to look for new kinds of particles which are not predicted by the Standard Model. One example is a particle with lepton number ±2, called a dilepton. We have studied the production of vector dileptons at hadron colliders in the context of a specific model: the 3-3-1 model. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57064

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

We discuss the feasibility of spontaneous CP violation being induced by radiative corrections in 2HDM’s. Specifically, we analyze the cases of gaugino/higgsino effect on MSSM, and a new model with an extra exotic quark doublet. The new model, while demonstrating well the Georgi-Pais theorem, is also expected to be phenomenlogically interesting. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57065

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

Hermitian mass matrices for the up and down quarks with texture zeroes but with the minimum number of parameters, ten, are investigated. We show how theseminimum parameterforms can be obtained from a general set of hermitian matrices through weak basis transformations. For the most simple forms we show that one can derive exact and compact parameterizations of the CKM mixing matrix in terms of the elements of these mass matrices (and the quark masses). ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57066

出版商:AIP    

年代:1998

数据来源: AIP