9,857 research outputs found
Determining the quantum numbers through a Kaon induced reaction
We study the reaction with kinematical condition suited to
the production of the resonance. It is shown that in this reaction
with the polarization experiment, a combined consideration of the strength at
the peak and the angular dependence of cross section can help determine the
quantum numbers.Comment: 4 pages, 3 figures, Talk given at International Workshop PENTAQUARK04
at SPring-8, Japan, July 20-23, 200
The scalar glueball spectrum
We discuss scenarios for scalar glueballs using arguments based on sum rules,
spectral decomposition, the approximation, the scales of the
strong interaction and the topology of the flux tubes. We analyze the
phenomenological support of those scenarios and their observational
implications. Our investigations hint a rich low lying glueball spectrum.Comment: 11 pages: New title, figure, table and a more detailed comparison
with experiment
Relationship between the column density distribution and evolutionary class of molecular clouds as viewed by ATLASGAL
We present the first study of the relationship between the column density
distribution of molecular clouds within nearby Galactic spiral arms and their
evolutionary status as measured from their stellar content. We analyze a sample
of 195 molecular clouds located at distances below 5.5 kpc, identified from the
ATLASGAL 870 micron data. We define three evolutionary classes within this
sample: starless clumps, star-forming clouds with associated young stellar
objects, and clouds associated with HII regions. We find that the N(H2)
probability density functions (N-PDFs) of these three classes of objects are
clearly different: the N-PDFs of starless clumps are narrowest and close to
log-normal in shape, while star-forming clouds and HII regions exhibit a
power-law shape over a wide range of column densities and log-normal-like
components only at low column densities. We use the N-PDFs to estimate the
evolutionary time-scales of the three classes of objects based on a simple
analytic model from literature. Finally, we show that the integral of the
N-PDFs, the dense gas mass fraction, depends on the total mass of the regions
as measured by ATLASGAL: more massive clouds contain greater relative amounts
of dense gas across all evolutionary classes.Comment: Accepted for publication in A&A (25th June 15) 23 pages, 12 figures.
Additional appendix figures will appear in the journal version of this pape
Evaluation of the scattering amplitude in the -channel at finite density
The scattering amplitude in the -channel is studied at
finite baryonic density in the framework of a chiral unitary approach which
successfully reproduces the meson meson phase shifts and generates the
and resonances in vacuum. We address here a new variety of mechanisms
recently suggested to modify the interaction in the medium, as well as
the role of the wave selfenergy, in addition to the wave, in the
dressing of the pion propagators.Comment: 26 pages, 17 figure
Out-of-plane seismic response of stone masonry walls: experimental and analytical study of real piers
This paper presents the application of an existing simplified displacement-based procedure to the
characterization of the nonlinear force-displacement relationship for the out-of-plane behaviour of
unreinforced traditional masonry walls. According to this procedure, tri-linear models based on three
different energy based criteria were constructed and confronted with three experimental tests on
existing stone masonry constructions. Moreover, a brief introduction is presented regarding the main
characteristics of the in situ cyclic testing recently carried out using distributed loads, as well as results
obtained during the experimental campaigns performed. The comparison between the experimental and the analytical results are presented and discussed
Lepton flavor violation in SUSY left-right symmetric theories
The seesaw mechanism is the most popular explanation for the smallness of
neutrino masses. However, its high scale makes direct tests impossible and only
indirect signals at low energies are reachable for collider experiments. One of
these indirect links with the high scale is lepton flavor violation (LFV). We
discuss LFV decays of sleptons in the context of a SUSY left-right symmetric
model that naturally incorporates the seesaw mechanism. This non-minimal
embedding of the seesaw leads to observable LFV effects in the right-handed
sleptons sector, contrary to minimal models where these are found to be totally
negligible. Therefore, LFV observables can be used as a powerful tool to study
physics right below the GUT scale.Comment: To appear in the proceedings of PASCOS 2010, the 16th International
Symposium on Particles, Strings and Cosmology, Valencia, Spai
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