8,012 research outputs found
BRST invariant formulation of spontaneously broken gauge theory in generalized differential geometry
Noncommutative geometry(NCG) on the discrete space successfully reproduces
the Higgs mechanism of the spontaneously broken gauge theory, in which the
Higgs boson field is regarded as a kind of gauge field on the discrete space.
We could construct the generalized differential geometry(GDG) on the discrete
space which is very close to NCG in case of .
GDG is a direct generalization of the differential geometry on the ordinary
manifold into the discrete one. In this paper, we attempt to construct the BRST
invariant formulation of spontaneously broken gauge theory based on GDG and
obtain the BRST invariant Lagrangian with the t'Hooft-Feynman gauge fixing
term.Comment: 15 page
Dense and Warm Molecular Gas between Double Nuclei of the Luminous Infrared Galaxy NGC 6240
High spatial resolution observations of the 12CO(1-0), HCN(1-0), HCO+(1-0),
and 13CO(1-0) molecular lines toward the luminous infrared merger NGC 6240 have
been performed using the Nobeyama Millimeter Array and the RAINBOW
Interferometer. All of the observed molecular emission lines are concentrated
in the region between the double nuclei of the galaxy. However, the
distributions of both HCN and HCO+ emissions are more compact compared with
that of 12CO, and they are not coincident with the star-forming regions. The
HCN/12CO line intensity ratio is 0.25; this suggests that most of the molecular
gas between the double nuclei is dense. A comparison of the observed high
HCN/13CO intensity ratio, 5.9, with large velocity gradient calculations
suggests that the molecular gas is dense [n(H_2)=10^{4-6} cm^-3] and warm
(T_kin>50 K). The observed structure in NGC 6240 may be explained by time
evolution of the molecular gas and star formation, which was induced by an
almost head-on collision or very close encounter of the two galactic nuclei
accompanied with the dense gas and star-forming regions.Comment: 25 pages, 8 figures, To be appeared in PASJ 57, No.4 (August 25,
2005) issu
Numerical Computation of Thermoelectric and Thermomagnetic Effects
Phenomenological equations describing the Seebeck, Hall, Nernst, Peltier,
Ettingshausen, and Righi-Leduc effects are numerically solved for the
temperature, electric current, and electrochemical potential distributions of
semiconductors under magnetic field. The results are compared to experiments.Comment: 4 pages, 7 figures. Submitted to Proceedings of XVII International
Conference on Thermoelectrics (ICT98), 1998 Nagoya, Japa
Modified Reconstruction of Standard Model in Non-Commutative Differential Geometry
Sogami recently proposed the new idea to express Higgs particle as a kind of
gauge particle by prescribing the generalized covariant derivative with gauge
and Higgs fields operating on quark and lepton fields. The field strengths for
both the gauge and Higgs fields are defined by the commutators of the covariant
derivative by which he could obtain the Yang-Mills Higgs Lagrangian in the
standard model. Inspired by Sogami's work, we present a modification of our
previous scheme to formulate the spontaneously broken gauge theory in
non-commutative geometry on the discrete space; Minkowski space multiplied by
two points space by introducing the generation mixing matrix in operation of
the generalized derivative on the more fundamental fields a_i(x,y) which
compose the gauge and Higgs fields. The standard model is reconstructed
according to the modified scheme, which does not yields not only any special
relations between the particle masses but also the special restriction on the
Higgs potential.Comment: 21 page
Photodissociation of Cl_2O at 248 and 308 nm
Molecular beam studies of Cl_2O photolysis at 248 and 308 nm have been repeated and the analysis refined. At 248 nm, three distinct dissociation pathways that led to Cl+ClO products were resolved. At 308 nm, the angular distribution was slightly more isotropic than previously reported, leaving open the possibility that Cl_2O excited at 308 nm lives longer than a rotational period
The Role of Torsion/Torsion Coupling in the Vibrational Spectrum of Cis−Cis HOONO
A three-dimensional model of the vibrational dynamics of HOONO is investigated. This model focuses on the couplings between the OH stretch vibration and the two torsions. The model is based on electronic energies, calculated at the CCSD(T)/cc-pVTZ level of theory and basis and dipole moment functions calculated at the CCSD/aug-cc-pVDZ level. The resulting points were fit to explicit functional forms, and the energies, wave functions, and intensities were evaluated using an approach in which the OH stretching motion was adiabatically separated from the torsional modes. It is found that the HOON torsion is strongly coupled to both the OONO torsion and OH stretch. Despite this, many of the conclusions that were drawn from earlier two-dimensional treatments, which did not include the OONO torsion, hold up on a semiquantitative level. In addition, we use this model to investigate the assignment of recently reported matrix isolated spectra of HOONO and DOONO. Finally, by comparing the results of this three-dimensional calculation to two-dimensional calculations and to the results of second-order perturbation theory, we investigate the question of how one determines the size of the reduced-dimensional system that is needed to describe the vibrational spectrum of molecules, like HOONO, that contain several large amplitude motions
BRST invariant Lagrangian of spontaneously broken gauge theories in noncommutative geometry
The quantization of spontaneously broken gauge theories in noncommutative
geometry(NCG) has been sought for some time, because quantization is crucial
for making the NCG approach a reliable and physically acceptable theory. Lee,
Hwang and Ne'eman recently succeeded in realizing the BRST quantization of
gauge theories in NCG in the matrix derivative approach proposed by Coquereaux
et al. The present author has proposed a characteristic formulation to
reconstruct a gauge theory in NCG on the discrete space .
Since this formulation is a generalization of the differential geometry on the
ordinary manifold to that on the discrete manifold, it is more familiar than
other approaches. In this paper, we show that within our formulation we can
obtain the BRST invariant Lagrangian in the same way as Lee, Hwang and Ne'eman
and apply it to the SU(2)U(1) gauge theory.Comment: RevTeX, page
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