1,166 research outputs found
H.E.S.S. observations of the Large Magellanic Cloud
The Large Magellanic Cloud (LMC) is a satellite galaxy of the Milky Way at a
distance of approximately 48 kpc. Despite its distance it harbours several
interesting targets for TeV gamma-ray observations. The composite supernova
remnant N 157B/PSR J05367-6910 was discovered by H.E.S.S. being an emitter of
very high energy (VHE) gamma-rays. It is the most distant pulsar wind nebula
ever detected in VHE gamma-rays. Another very exciting target is SN 1987A, the
remnant of the most recent supernova explosion that occurred in the
neighbourhood of the Milky Way. Models for Cosmic Ray acceleration in this
remnant predict gamma-ray emission at a level detectable by H.E.S.S. but this
has not been detected so far. Fermi/LAT discovered diffuse high energy (HE)
gamma-ray emission from the general direction of the massive star forming
region 30 Doradus but no clear evidence for emission from either N 157B or SN
1987A has been published. The part of the LMC containing these objects has been
observed regularly with the H.E.S.S. telescopes since 2003. With deep
observations carried out in 2010 a very good exposure of this part of the sky
has been obtained. The current status of the H.E.S.S. LMC observations is
reported along with new results on N 157B and SN 1987A.Comment: 4 pages, 3 figures, proceedings of the 32nd Internatioal Cosmic Ray
Conference, Beijing 201
A Population of Teraelectronvolt Pulsar Wind Nebulae in the H.E.S.S. Galactic Plane Survey
The most numerous source class that emerged from the H.E.S.S. Galactic Plane
Survey are Pulsar Wind Nebulae (PWNe). The 2013 reanalysis of this survey,
undertaken after almost 10 years of observations, provides us with the most
sensitive and most complete census of gamma-ray PWNe to date. In addition to a
uniform analysis of spectral and morphological parameters, for the first time
also flux upper limits for energetic young pulsars were extracted from the
data. We present a discussion of the correlation between energetic pulsars and
TeV objects, and their respective properties. We will put the results in
context with the current theoretical understanding of PWNe and evaluate the
plausibility of previously non-established PWN candidates.Comment: 4 pages, 5 figures. In Proceedings of the 33rd International Cosmic
Ray Conference (ICRC2013), Rio de Janeiro (Brazil
Phase Relations in the Li2O-V2O3-V2O5 System at 700 C: Correlations with Magnetic Defect Concentration in Heavy Fermion LiV2O4
The phase relations in the Li2O-V2O3-V2O5 ternary system at 700 C for
compositions in equilibrium with LiV2O4 are reported. This study clarified the
synthesis conditions under which low and high magnetic defect concentrations
can be obtained within the spinel structure of LiV2O4. We confirmed that the
LiV2O4 phase can be obtained containing low (0.006 mol%) to high (0.83 mol%)
magnetic defect concentrations n{defect} and with consistently high magnetic
defect spin S values between 3 and 6.5. The high n{defect} values were obtained
in the LiV2O4 phase in equilibrium with V2O3, Li3VO4, or LiVO2 and the low
values in the LiV2O4 phase in equilibrium with V3O5. A model is suggested to
explain this correlation.Comment: 6 pages, 7 figures; Phys. Rev. B (accepted
The Full Spectrum Galactic Terrarium: MHz to TeV Observations of Various Critters
Multi-wavelength studies at radio, infrared, optical, X-ray, and TeV
wavelengths have discovered probable counterparts to many Galactic sources of
GeV emission detected by EGRET. These include pulsar wind nebulae, high mass
X-ray binaries, and mixed morphology supernova remnants. Here we provide an
overview of the observational properties of Galactic sources which emit across
19 orders of magnitude in energy. We also present new observations of several
sources.Comment: 4 pages, 5 figures, Proceedings of the The 4th Heidelberg
International Symposium on High Energy Gamma-Ray Astronomy, eds. Aharonian,
Hofmann, Riege
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