12,572 research outputs found
Crystal Barrel Results on Two-Body Decays of the Scalar Glueball
The Crystal Barrel Collaboration observes scalar meson resonances in annihilation. Based on the measurements and partial wave analyses these are
candidates for the P groundstate nonet. The supernummerary
resonance is identified as a scalar groundstate glueball. Important information
for its characterization comes from the decay pattern into pseudoscalar and
scalar mesons. Data on kaonic decays in the mass region up to 1700 MeV are now
avaible at Crystal Barrel. New analysis results are presented.Comment: 5 pages, Latex, 3 eps figures, talk presented at EPS-HEP'97
conference in Jerusalem, Israel, 19-26 Aug. 199
A spatially resolved SSC Shock-in-Jet model
In this paper a spatially resolved, fully self-consistent SSC model is
presented. The observable spectral energy distribution (SED) evolves entirely
from a low energetic delta distribution of injected electrons by means of the
implemented microphysics of the jet. These are in particular the properties of
the shock and the ambient plasma, which can be varied along the jet axis. Hence
a large variety of scenarios can be computed, e.g. the acceleration of
particles via multiple shocks. Two acceleration processes, shock acceleration
and stochastic acceleration, are taken into account. From the resulting
electron distribution the SED is calculated taking into account synchrotron
radiation, inverse Compton scattering (full cross section) and synchrotron self
absorption. The model can explain SEDs where cooling processes are crucial. It
can verify high variability results from acausal simulations and produce
variability not only via injection of particles, but due to the presence of
multiple shocks. Furthermore a fit of the data, obtained in the 2010
multi-frequency campaign of Mrk501, is presented.Comment: 4 pages, 2 figures; appeared in the proceedings of the conference:
"High Energy Phenomena in Relativistic Outflows (HEPRO) III", held in
Barcelona, Spain, June 27th-July 1st 2011 (IJMPCS
Three-wave interactions of dispersive plasma waves propagating parallel to the magnetic field
Three-wave interactions of plasma waves propagating parallel to the mean
magnetic field at frequencies below the electron cyclotron frequency are
considered. We consider Alfv\'en--ion-cyclotron waves,
fast-magnetosonic--whistler waves, and ion-sound waves. Especially the weakly
turbulent low-beta plasmas like the solar corona are studied, using the
cold-plasma dispersion relation for the transverse waves and the
fluid-description of the warm plasma for the longitudinal waves. We analyse the
resonance conditions for the wave frequencies and wavenumbers , and
the interaction rates of the waves for all possible combinations of the three
wave modes, and list those reactions that are not forbidden.Comment: accepted for publication in Advanced Science Letter
The radio morphology of a spatially resolved SSC model
One of the main, unresolved questions about the nature of quasars is the
position of the acceleration site responsible for the highest energies. The
attempt to investigate this question in the energy regime with the highest
resolution, the radio band, has the downside that no theoretical model exists
that can connect these two regimes. The model in this work tries to shrink this
gap by extending the general synchrotron self Compton (SSC) model up to length
scales in the order of the resolution of radio observations. The resulting
spectral energy distributions (SED) show a qualitative improvement in the
representation of the radio spectrum. Furthermore the obtained emission
morphology shows similar properties to the radio structures observed in jets of
quasars. A complete and quantitative connection will however need either much
higher numerical effort or an improved methodology
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