27,712 research outputs found
Semiclassical Meson-Baryon Dynamics from Large-Nc QCD
The large- limit of the meson-baryon effective Lagrangian is shown to
reduce to a semiclassical field theory. A chiral bag structure emerges
naturally in the limit. A possible connection between
the chiral bag picture and the Skyrme model is discussed. The classical
meson-baryon theory is used to reproduce the non-analytic correction
to the baryon mass obtained previously as a loop correction in chiral
perturbation theory.Comment: (13 pages, 1 figure, uses harvmac and uufiles), UCSD/PTH 94-1
Minimally Allowed Neutrinoless Double Beta Decay Rates From Approximate Flavor Symmetries
Neutrinoless double beta decay () is among the only realistic
probes of Majorana neutrinos. In the standard scenario, dominated by light
neutrino exchange, the process amplitude is proportional to , the
element of the Majorana mass matrix. Naively, current data allows for vanishing
, but this should be protected by an appropriate flavor symmetry. All
such symmetries lead to mass matrices inconsistent with oscillation
phenomenology. I perform a spurion analysis to break all possible Abelian
symmetries that guarantee vanishing rates and search for
minimally allowed values. I survey 230 broken structures to yield
values and current phenomenological constraints under a variety of scenarios.
This analysis also extracts predictions for both neutrino oscillation
parameters and kinematic quantities. Assuming reasonable tuning levels, I find
that eV at 99% confidence. Bounds below this value
might indicate the Dirac neutrino nature or the existence of new light (eV-MeV
scale) degrees of freedom that can potentially be probed elsewhere.Comment: 19 Pages, 4 .eps Figures, 3 Table
Ichthyofaunal Diversification and Distribution in the Big Creek Watershed, Craighead and Greene Counties, Arkansas
Big Creek is a relatively small deltaic stream, in northeastern Arkansas, in an area of intense cultivation. Recently it has been dredged in the interest of flood control. Lost Creek and Mud Creek are the major tributaries of Big Creek and collectively drain the Big Creek watershed. The streams were found to have relatively low alkalinity, moderate carbon dioxide, adequate oxygen values, and relatively high turbidity. Channeling of Big Creek and Lost Creek has effectively destroyed distinct pool-riffle biocies and reduced the number of acceptable spawning areas. Lost Creek, also, receives effluent from residential dwellings, a secondary treatment sewage plant, and a meat rendering plant. Mud Creek, in the absence of channeling and deleterious effects of effluents, provided a relatively greater diversity of habitat than did Big Creek or Lost Creek
Heavy Baryon Masses in Large N_c HQET
We argue that in the large N_c HQET, the masses of the s-wave low-spin heavy
baryons equal to the heavy quark mass plus proton mass approximately. To the
subleading order, the heavy baryon mass 1/N_c expansion not only has the same
form, but also has the same coefficients as that of the light baryon. Based on
this, numerical analysis is made.Comment: 7 pages, latex, no figures, to appear in Phys. Lett.
A model for the onset of oscillations near the stopping angle in an inclined granular flow
We propose an explanation for the onset of oscillations seen in numerical
simulations of dense, inclined flows of inelastic, frictional spheres. It is
based on a phase transition between disordered and ordered collisional states
that may be interrupted by the formation of force chains. Low frequency
oscillations between ordered and disordered states take place over weakly bumpy
bases; higher-frequency oscillations over strongly bumpy bases involve the
formation of particle chains that extend to the base and interrupt the phase
change. The predicted frequency and amplitude of the oscillations induced by
the unstable part of the equation of state are similar to those seen in the
simulations and they depend upon the contact stiffness in the same way. Such
oscillations could be the source of sound produced by flowing sand
Was the Accounting Profession Really That Bad?
To gain insight into the extent of malpractice in the State of California prior to the Passage of Sarbanes-Oxley, we examined the nature and magnitude of complains filed with the California Board of Accountancy (CBA) against both licensed and unlicensed accountants during the fiscal years 2000, 2001, and 2002. The CBA currently licenses and regulates over 73,000 licenses, with 1,431 complaints filed during the period reviewed. Disciplinary actions were taken against 283 different licensees for the three fiscal years reviewed. SEC issues were involved in 19 cases, theft or embezzlement 46 cases, public accounting malpractice 146 cases, improper retention of client records 11 cases, cheating on the CPA examination 9 cases, and miscellaneous other 52 cases. Over half of the complaints involved public accounting issues. Audit related complaints accounted for 48%, tax related complaints 36%, and compilations or reviews accounted for 16% of the complaints. These statistics were in line with the experience of the AICPA Professional Liability program. Within the above sections, the paper contains specifics with regards to the most common problems identified as a result of this work. While a number of interesting facts were discovered, one item of particularly interest was the significant number of claims that involved non-profit organizations. CBA administrators do not believe there is any greater tendency for non profit reporting versus for profit reporting, thus appearing to indicate this is just an area that has a greater possibility of accounting malpractice
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