5,900 research outputs found
Light-cone Gauge Superstring Field Theory and Dimensional Regularization II
We propose a dimensional regularization scheme to deal with the divergences
caused by colliding supercurrents inserted at the interaction points, in the
light-cone gauge NSR superstring field theory. We formulate the theory in
dimensions and define the amplitudes as analytic functions of . With an
appropriately chosen three-string interaction term and large negative , the
tree level amplitudes for the (NS,NS) closed strings can be recast into a BRST
invariant form, using the superconformal field theory proposed in
Ref.[arXiv:0911.3704]. We show that in the limit they coincide with
the results of the first quantized theory. Therefore we obtain the desired
results without adding any contact interaction terms to the action.Comment: 23 pages; v2: minor modifications; v3: revised argument in section 3,
added appendix C, results unchanged; v4: added clarifications, two figures
and a footnote; v5: minor modification
Quality Management of the Accounting Services
Often, the accounting services are vital for the success of a business, and their quality is very important, both for the users of accounting information, as well as for the providers of services.The present paper highlights the role of the accounting services in the processes of planning, coordination and development of the management policies of the economic entities. There a re identified a series of factors which are responsible for the quality of the accounting process and for the efficiency of the activity undertaken by the accountants
Spacetime Fermions in Light-cone Gauge Superstring Field Theory and Dimensional Regularization
We consider the dimensional regularization of the light-cone gauge type II
superstring field theories in the NSR formalism. In the previous work, we have
calculated the tree-level amplitudes with external lines in the (NS,NS) sector
using the regularization and shown that the desired results are obtained
without introducing contact term interactions. In this work, we study the
tree-level amplitudes with external lines in the Ramond sector. In order to
deal with them, we propose a worldsheet theory to be used instead of that for
the naive dimensional regularization. With the worldsheet theory, we regularize
and define the tree-level amplitudes by analytic continuation. We show that the
results coincide with those of the first quantized formulation.Comment: 28 pages, 5 figures; v2: more details of our manipulations in
subsection 3.2 added, figures and references added; v3: clarifications adde
Compositon of Tantalum Nitride Thin Films Grown by Low-Energy Nitrogen Implantation: A Factor Analysis Study of the Ta 4f XPS Core Level
Tantalum nitride thin films have been grown by in situ nitrogen implantation
of metallic tantalum at room temperature over the energy range of 0.5-5keV.
X-ray photoelectron spectroscopy (XPS) and Factor Analysis (FA) have been used
to characterise the chemical composition of the films. The number of the
different Ta-N phases formed during nitrogen implantation, as well as their
spectral shape and concentrations, have been obtained using principal component
analysis (PCA) and iterative target transformation factor analysis (ITTFA),
without any prior assumptions. According to FA results, the composition of the
tantalum nitride films depends on both the ion dose and ion energy, and is
mainly formed by a mixture of metallic tantalum, beta-TaN0.05, gamma-Ta2N and
cubic/hexagonal TaN phases.Comment: 24 pages, 5 figures submitted to Applied Physics
Light-cone Gauge NSR Strings in Noncritical Dimensions II -- Ramond Sector
Light-cone gauge superstring theory in noncritical dimensions corresponds to
a worldsheet theory with nonstandard longitudinal part in the conformal gauge.
The longitudinal part of the worldsheet theory is a superconformal field theory
called X^{\pm} CFT. We show that the X^{\pm} CFT combined with the
super-reparametrization ghost system can be described by free variables. It is
possible to express the correlation functions in terms of these free variables.
Bosonizing the free variables, we construct the spin fields and BRST invariant
vertex operators for the Ramond sector in the conformal gauge formulation. By
using these vertex operators, we can rewrite the tree amplitudes of the
noncritical light-cone gauge string field theory, with external lines in the
(R,R) sector as well as those in the (NS,NS) sector, in a BRST invariant way.Comment: 33 pages; v2: minor modification
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