54,718 research outputs found
Decaying dark matter with heavy axino
A TeV scale decaying dark matter chiral multiplet N is introduced in addition
to the minimal supersymmetric standard model(MSSM). For a calculable abundance
of N, we introduce heavy axino decaying to N and MSSM particles including the
lightest supersymmetric particle(LSP). In the scenario that heavy axino, once
dominating the energy density of the universe, decays after the LSP decouples,
it is possible to estimate the relative cosmic abundances of N and the LSP.
Dimension 6 interactions allow the lifetime of the fermionic or the bosonic
superpartner of N in the 10^{27} s range to be compatible with the recent
astrophysical bounds. A diagrammatic strategy obtaining a suppression factor
1/M^2 is also given.Comment: 5 pages with 2 figure
BRST Invariant Higher Derivative Operators in 4D Quantum Gravity based on CFT
We continue the study of physical fields for the background free 4D quantum
gravity based on the Riegert-Wess-Zumino action, developed in Phys. Rev. D {\bf
85} (2012) 024028. The background free model is formulated in terms of a
certain conformal field theory on M^4 in which conformal symmetry arises as
gauge symmetry, namely diffeomorphism invariance. In this paper, we construct
the physical field operator corresponding to any integer power of Ricci scalar
curvature in the context of the BRST quantization. We also discuss how to
define the correlation function and its physical meanings.Comment: 22 pages, minor typo corrected, published versio
Distribution of slip from 11 M_w > 6 earthquakes in the northern Chile subduction zone
We use interferometric synthetic aperture radar, GPS, and teleseismic data to constrain the relative location of coseismic slip from 11 earthquakes on the subduction interface in northern Chile (23°–25°S) between the years 1993 and 2000. We invert body wave waveforms and geodetic data both jointly and separately for the four largest earthquakes during this time period (1993 M_w 6.8; 1995 M_w 8.1; 1996 M_w 6.7; 1998 M_w 7.1). While the location of slip in the teleseismic-only, geodetic-only, and joint slip inversions is similar for the small earthquakes, there are differences for the 1995 M_w 8.1 event, probably related to nonuniqueness of models that fit the teleseismic data. There is a consistent mislocation of the Harvard centroid moment tensor locations of many of the 6 6 earthquakes, as well as three M_w > 7 events from the 1980s. All of these earthquakes appear to rupture different portions of the fault interface and do not rerupture a limited number of asperities
On baryon-antibaryon coupling to two photons
We discuss recent claims that may be described
by a generalized parton picture. We propose that quark-hadron duality provides
a justification for the effective dominance of the "handbag" diagram assumed in
recent literature, and that handbag diagrams may dominate phenomena in
kinematic regions far more extensive than that might be expected from pQCD
alone.Comment: 11 pages, 2 eps figures, minor modifications made, version to appear
on Phys. Lett.
Background Free Quantum Gravity based on Conformal Gravity and Conformal Field Theory on M^4
We study four dimensional quantum gravity formulated as a certain conformal
field theory at the ultraviolet fixed point, whose dynamics is described by the
combined system of Riegert-Wess-Zumino and Weyl actions. Background free nature
comes out as quantum diffeomorphism symmetry by quantizing the conformal factor
of the metric field nonperturbatively. In this paper, Minkowski background M^4
is employed in practice. The generator of quantum diffeomorphism that forms
conformal algebra is constructed. Using it, we study the composite scalar
operator that becomes a good conformal field. We find that physical fields are
described by such scalar fields with conformal dimension 4. Consequently,
tensor fields outside the unitarity bound are excluded. Computations of quantum
algebra on M^4 are carried out in the coordinate space using operator products
of the fields. The nilpotent BRST operator is also constructed.Comment: 43 pages, eqs.(3.9) and (6.18) correcte
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