30 research outputs found
Modeling of chemical processes in the low pressure capacitive RF discharges in a mixture of Ar/C2H2
We study the properties of a capacitive 13.56 MHz discharge properties with a
mixture of Ar/C2H2 taking into account the plasmochemistry and growth of heavy
hydrocarbons. A hybrid model was developed to combine the kinetic description
for electron motion and the fluid approach for negative and positive ions
transport and plasmochemical processes. A significant change of plasma
parameters related to injection of 5.8% portion of acetylene in argon was
observed and analyzed. We found that the electronegativity of the mixture is
about 30%. The densities of negatively and positively charged heavy
hydrocarbons are sufficiently large to be precursors for the formation of
nanoparticles in the discharge volume.Comment: 11 pages, 14 figure
Observation of VHE Gamma Radiation from HESS J1834-087/W41 with the MAGIC Telescope
Recently, the HESS array has reported the detection of gamma-ray emission
above a few hundred GeV from eight new sources located close to the Galactic
Plane. The source HESS J1834-087 is spatially coincident with SNR G23.3-0.3
(W41). Here we present MAGIC observations of this source, resulting in the
detection of a differential gamma-ray flux consistent with a power law,
described as dN/(dA dt dE) = (3.7 +/- 0.6)*10^(-12) (E/TeV)^(-2.5 +/- 0.2) \
cm^(-2)s^(-1)TeV^(-1). We confirm the extended character of this flux. We
briefly discuss the observational technique used, the procedure implemented for
the data analysis, and put this detection in the perspective of the molecular
environment found in the region of W41. We present 13CO and 12CO emission maps
showing the existence of a massive molecular cloud in spatial superposition
with the MAGIC detection.Comment: Accepted by ApJ Letter