1,497 research outputs found
Inducing the mu and the B mu Term by the Radion and the 5d Chern-Simons Term
In 5-dimensional models with gauge-Higgs unification, the F-term vacuum
expectation value of the radion provides, in close analogy to the
Giudice-Masiero mechanism, a natural source for the mu and B mu term. Both the
leading order gauge theory lagrangian and the supersymmetric Chern-Simons term
contain couplings to the radion superfield which can be used for this purpose.
We analyse the basic features of this mechanism for mu term generation and
provide an explicit example, based on a variation of the SU(6) gauge-Higgs
unification model of Burdman and Nomura. This construction contains all the
relevant features used in our generic analysis. More generally, we expect our
mechanism to be relevant to many of the recently discussed orbifold GUT models
derived from heterotic string theory. This provides an interesting way of
testing high-scale physics via Higgs mass patterns accessible at the LHC.Comment: 23 pages, LaTeX, 1 figure, concrete model significantly improved,
references adde
Big Bang Synthesis of Nuclear Dark Matter
We investigate the physics of dark matter models featuring composite bound
states carrying a large conserved dark "nucleon" number. The properties of
sufficiently large dark nuclei may obey simple scaling laws, and we find that
this scaling can determine the number distribution of nuclei resulting from Big
Bang Dark Nucleosynthesis. For plausible models of asymmetric dark matter, dark
nuclei of large nucleon number, e.g. > 10^8, may be synthesised, with the
number distribution taking one of two characteristic forms. If
small-nucleon-number fusions are sufficiently fast, the distribution of dark
nuclei takes on a logarithmically-peaked, universal form, independent of many
details of the initial conditions and small-number interactions. In the case of
a substantial bottleneck to nucleosynthesis for small dark nuclei, we find the
surprising result that even larger nuclei, with size >> 10^8, are often finally
synthesised, again with a simple number distribution. We briefly discuss the
constraints arising from the novel dark sector energetics, and the extended set
of (often parametrically light) dark sector states that can occur in complete
models of nuclear dark matter. The physics of the coherent enhancement of
direct detection signals, the nature of the accompanying dark-sector form
factors, and the possible modifications to astrophysical processes are
discussed in detail in a companion paper.Comment: 27 pages, 5 figures, v3; minor additional comments - matches
published versio
Schoolwide behavior support: creating urban schools that accommodate diverse learners
Journal ArticleToday's educators face a growing challenge to meet both the instructional and behavioral needs of all students (Kame'enui & Carnine, 1998; Martella, Nelson, & Marchand-Martella, 2003; Sugai, Kame'enui, Horner, & Simmons, 2002). The No Child Left Behind Act of 2001 has called for educational practices that will prepare all children to be responsible and positive contributors to society
The Population Dynamics of Two Rodents in Two Coastal Marshes in Virginia
The communities of small mammals were evaluated for 13 months with capture-mark-recapture methods in two Spartina-Juncus marshes of the Atlantic coast in Northampton County, Virginia. Small mammals were trapped for three days each month using live traps placed on floats on two study grids. Two rodents were numerically dominant (~90% of small mammals) there: marsh rice rat, Oryzomys palustris, and meadow vole, Microtus pennsylvanicus. Monthly estimates of population density were greater for rice rats (peak: 45/ha) than for those of meadow voles (peak: 30/ha). Survival rates were generally low, especially for rice rats, indicating highly vagile populations. Both species had greatest breeding activity in spring and autumn, with lower rates in summer and winter. Sex ratios favored males in rice rats but were unity in meadow voles. Although marsh rice rats, being semi-aquatic and capable swimmers, are more highly adapted to living in flooded marsh environments, meadow voles can thrive there too
Ressenya a Vicent J. Escartí (ed.), Nunc dimittis. Estudis dedicats al professor Antoni Ferrando, València, 2019
Ressenya a Vicent J. Escartí (ed.), Nunc dimittis. Estudis dedicats al professor Antoni Ferrando, València, PUV, 2019, pp. 596, ISBN: 978-84-9134-370-7 Review to Vicent J. Escartí (ed.), Nunc dimittis. Estudis dedicats al professor Antoni Ferrando, València, PUV, 2019, pp. 596, ISBN: 978-84-9134-370-
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