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Comment on "Material Evidence of a 38 MeV Boson"
In the recent preprint 1202.1739 it was claimed that preliminary data
presented by COMPASS at recent conferences confirm the existence of a resonant
state of mass 38 MeV decaying to two photons. This claim was made based on
structures observed in two-photon mass distributions which however were shown
only to demonstrate the purity and mass resolution of the {\pi}0 and {\eta}
signals. The additional structures are understood as remnants of secondary
interactions inside the COMPASS spectrometer. Therefore, the COMPASS data do
not confirm the existence of this state.Comment: 2 pages, 7 figure
Killing spinors in supergravity with 4-fluxes
We study the spinorial Killing equation of supergravity involving a torsion
3-form \T as well as a flux 4-form \F. In dimension seven, we construct
explicit families of compact solutions out of 3-Sasakian geometries, nearly
parallel \G_2-geometries and on the homogeneous Aloff-Wallach space. The
constraint \F \cdot \Psi = 0 defines a non empty subfamily of solutions. We
investigate the constraint \T \cdot \Psi = 0, too, and show that it singles
out a very special choice of numerical parameters in the Killing equation,
which can also be justified geometrically
Application of a novel method for subsequent evaluation of sinusoids and postsinusoidal venules after ischemia-reperfusion injury of rat liver
Although several intravital fluorescence microscopic studies demonstrated that microcirculatory derangement is induced during liver ischemia-reperfusion, these data were obtained from randomly selected microvascular areas and microvessels, Repeated observation of the identical microvessels has not been performed yet. Using a specially designed cover glass, it is now possible to relocate desired sites of observation repeatedly over the whole reperfusion time, The aim of this study was to determine the impact of reperfusion time on hepatic microvascular perfusion state. Twenty minutes of ischemia induced a significant decrease in sinusoidal perfusion rate (29.1 +/- 10.2%) as compared with baseline values (98.0 +/- 0.3%). At 30, 60, and 120 min of reperfusion, the percentage of perfused sinusoids recovered to 62.8 +/- 6.6, 67.5 +/- 5.7, and 77.2 +/- 5.4%. The number of stagnant leukocytes in the same sinusoids was 6.2 +/- 1.9/lobule at baseline and increased to 22.3 +/- 3.6/lobule at 120 min of reperfusion. The number of leukocytes adhering within postsinusoidal venules was 53.5 +/- 12.5/mm(2) before ischemia and increased to 414.2 +/- 62.5/mm(2) at 120 min of reperfusion. We have demonstrated that during 120 min of reperfusion, there was a steady increase in both sinusoidal and venular leukocyte adhesion along with an attenuation of the initially severely depressed sinusoidal perfusion. a no-reflow phenomenon at an early phase of reperfusion and subsequent reflow were proven
Numerical treatment of the hyperboloidal initial value problem for the vacuum Einstein equations. I. The conformal field equations
This is the first in a series of articles on the numerical solution of
Friedrich's conformal field equations for Einstein's theory of gravity. We will
discuss in this paper why one should be interested in applying the conformal
method to physical problems and why there is good hope that this might even be
a good idea from the numerical point of view. We describe in detail the
derivation of the conformal field equations in the spinor formalism which we
use for the implementation of the equations, and present all the equations as a
reference for future work. Finally, we discuss the implications of the
assumptions of a continuous symmetry.Comment: 19 pages, LaTeX2
Deformed Base Antisymmetrized Molecular Dynamics and its Application to ^{20}Ne
A new theoretical framework named as deformed base antisymmetrized molecular
dynamics that uses the localized triaxially deformed Gaussian as the single
particle wave packet is presented. The model space enables us to describe
sufficiently well the deformed mean-field structure as well as the cluster
structure and their mixed structure within the same framework. The improvement
over the original version of the antisymmetrized molecular dynamics which uses
the spherical Gaussian is verified by the application to
nucleus. The almost pure cluster structure of the
= band, the distortion of the cluster structure in the
= band and the dominance of the deformed mean-field structure of
the = band are confirmed and their observed properties are
reproduced. Especially, the intra-band E2 transition probabilities in
= and bands are reproduced without any effective charge.
Since it has been long known that the pure
cluster model underestimates the intra-band transitions in the
= band by about 30%, we consider that this success is due to the
sufficient description of the deformed mean-field structure in addition to the
cluster structure by the present framework. From the successful description of
, we expect that the present framework presents us with a
powerful approach for the study of the coexistence and interplay of the
mean-field structure and the cluster structure
On a choice of the Bondi radial coordinate and news function for the axisymmetric two-body problem
In the Bondi formulation of the axisymmetric vacuum Einstein equations, we
argue that the ``surface area'' coordinate condition determining the ``radial''
coordinate can be considered as part of the initial data and should be chosen
in a way that gives information about the physical problem whose solution is
sought. For the two-body problem, we choose this coordinate by imposing a
condition that allows it to be interpreted, near infinity, as the (inverse of
the) Newtonian potential. In this way, two quantities that specify the problem
-- the separation of the two particles and their mass ratio -- enter the
equations from the very beginning. The asymptotic solution (near infinity) is
obtained and a natural identification of the Bondi "news function" in terms of
the source parameters is suggested, leading to an expression for the radiated
energy that differs from the standard quadrupole formula but agrees with recent
non-linear calculations. When the free function of time describing the
separation of the two particles is chosen so as to make the new expression
agree with the classical result, closed-form analytic expressions are obtained,
the resulting metric approaching the Schwarzschild solution with time. As all
physical quantities are defined with respect to the flat metric at infinity,
the physical interpretation of this solution depends strongly on how these
definitions are extended to the near-zone and, in particular, how the "time"
function in the near-zone is related to Bondi's null coordinate.Comment: 13 pages, LaTeX, submitted to Classical and Quantum Gravity; v2
corrected a few typos and added some comments; v3 expanded discussion and
added references -- Rejected by CQG; v4: 8 pages revtex4 2 column,
extensively revised, submitted to Phys Rev D; v5: 21 pages revtex4 preprint;
further discussion of physical interpretation; v6: 21 pages revtex4 preprint
-- final version to appear in Phys. Rev. D (2006
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