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A Higher-Order Energy Expansion to Two-Dimensional Singularly Neumann Problems
Of concern is the
following singularly perturbed semilinear elliptic problem
\begin{equation*}
\left\{ \begin{array}{c}
\mbox{ in }\\
\mbox{ in and on },
\end{array}
\right.
\end{equation*}
where is a bounded domain in with smooth
boundary , is a small constant and
. Associated with the
above problem is the energy functional defined by
\begin{equation*}
J_{\epsilon}[u]:=\int_{\Omega}\left(\frac{\epsilon^2}{2}{|\nabla
u|}^2 +\frac{1}{2}u^2 -F(u)\right)dx
\end{equation*}
for , where .
Ni and Takagi (\cite{nt1}, \cite{nt2}) proved that for a single
boundary spike solution , the following asymptotic
expansion holds:
\begin{equation*}
(1) \ \ \ \ \ \ \ \ J_{\epsilon}[u_{\epsilon}]=\epsilon^{N}
\left[\frac{1}{2}I[w]-c_1 \epsilon
H(P_{\epsilon})+o(\epsilon)\right],
\end{equation*}
where is the energy of the ground state, is a
generic constant, is the unique local maximum point
of and is the boundary mean
curvature function at . Later,
Wei and Winter (\cite{ww3}, \cite{ww4}) improved the result and
obtained a higher-order expansion of :
\begin{equation*}
(2) \ \ \ \ \ \ J_{\epsilon}[u_{\epsilon}]=\epsilon^{N}
\left[\frac{1}{2}I[\omega]-c_{1} \epsilon
H(P_{\epsilon})+\epsilon^2 [c_2(H(P_\epsilon))^2 +c_{3}
R(P_\epsilon)]+o(\epsilon^2)\right],
\end{equation*}
where and are generic constants and
is the scalar curvature at . However, if , the
scalar curvature is always zero. The expansion (2) is no longer sufficient to distinguish spike locations with same mean curvature.
In this paper, we consider
this case and assume that . Without loss of generality, we may assume that the
boundary near P\in\partial\Om is represented by the graph . Then we have the following higher order expansion of
\begin{equation*}
(3) \ \ \ \ \ J_\epsilon [u_\epsilon]
=\epsilon^N \left[\frac{1}{2}I[w]-c_1
\epsilon H({P_\epsilon})+c_2 \epsilon^2(H({P_\epsilon}))^2 ]
+\epsilon^3
[P(H({P_\epsilon}))+c_3S({P_\epsilon})]+o(\epsilon^3)\right],
\end{equation*}
where H(P_\ep)= \rho_{P_\ep}^{''} (0) is the curvature, is a polynomial,
, , and , , are generic real
constants and S(P_\epsilon)= \rho_{P_\ep}^{(4)} (0). In
particular . Some applications of this expansion are given
Large gauge invariant non-standard neutrino interactions
Theories beyond the Standard Model must necessarily respect its gauge
symmetry. This implies strict constraints on the possible models of
non-standard neutrino interactions, which we analyze. The focus is set on the
effective low-energy dimension six and eight operators involving four leptons,
decomposing them according to all possible tree-level mediators, as a guide for
model building. The new couplings are required to have sizeable strength, while
processes involving four charged leptons are required to be suppressed. For
non-standard interactions in matter, only diagonal tau-neutrino interactions
can escape these requirements and can be allowed to result from dimension six
operators. Large non-standard neutrino interactions from dimension eight
operators alone are phenomenologically allowed in all flavour channels and
shown to require at least two new mediator particles. The new couplings must
obey general cancellation conditions both at the dimension six and eight
levels, which result from expressing the operators obtained from the mediator
analysis in terms of a complete basis of operators. We illustrate with one
example how to apply this information to model building.Comment: 34 pages, 4 figures, 5 tables. Final version in PR
Optical and X-ray Properties of the Swift BAT-detected AGN
The Swift Gamma-Ray Burst satellite has detected a largely unbiased towards
absorption sample of local () AGN, based solely on their
14--195 keV flux. In the first 9 months of the survey, 153 AGN sources were
detected. The X-ray properties in the 0.3--10 keV band have been compiled and
presented based on analyses with XMM-Newton, Chandra, Suzaku, and the Swift XRT
(Winter et al. 2009). Additionally, we have compiled a sub-sample of sources
with medium resolution optical ground-based spectra from the SDSS or our own
observations at KPNO. In this sample of 60 sources, we have classified the
sources using standard emission line diagnostic plots, obtained masses for the
broad line sources through measurement of the broad H emission line, and
measured the [OIII] 5007\AA luminosity of this sample. Based on continuum fits
to the intrinsic absorption features, we have obtained clues about the stellar
populations of the host galaxies. We now present the highlights of our X-ray
and optical studies of this unique sample of local AGNs, including a comparison
of the 2--10 keV and 14--195 keV X-ray luminosities with the [OIII] 5007\AA
luminosity and the implications of our results towards measurements of
bolometric luminosities.Comment: 4 pages, 2 figures, to appear in proceedings for 'X-ray Astronomy
2009', Bologna 09/2009, AIP Conference Series, Eds. A. Comastri, M. Cappi, L.
Angelin
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