The High-Altitude Water Cherenkov (HAWC) TeV Gamma-Ray Observatory located at a site about two hours drive east of Puebla, Mexico on the Sierra Negra plateau (4100 m a.s.l.) was inaugurated in March ...2015. The array of 300 water Cherenkov detectors can observe large portions of the sky simultaneously and, with an energy range of 100 GeV to 100 TeV, is currently one of the most sensitive instruments capable of probing particle acceleration near PeV energies. HAWC has already started science operation in the Summer of 2013 and preliminary sky maps have been produced from 260 days of data taken with a partial array. Multiple > 5 σ (pre-trials) hotspots are visible along the galactic plane and some appear to coincide with known TeV sources from the H.E.S.S. catalog, SNRs and molecular cloud associations, and pulsars wind nebulae (PWNe). The sky maps based on partial HAWC array data are discussed as well as the scientific potential of the completed instrument especially in the context of multi-wavelengths studies.
The High Altitude Water Cherenkov (HAWC) Observatory is a wide-field-of-view gamma-ray observatory that is optimized to detect gamma rays between 300 GeV and several hundred TeV. The HAWC ...Collaboration recently released their third source catalog (3HWC), which contains 65 sources. One of these sources, the ultra-high-energy gamma-ray source 3HWC J1908+063, may exhibit a hardening of the spectral index at the highest energies (above 56 TeV). At least two populations of particles are needed to satisfactorily explain the highest energy emission. This second component could be leptonic or hadronic in origin. If it is hadronic in origin, it would imply the presence of protons with energies up to ~1 PeV near the source. We have searched other 3HWC sources for the presence of this spectral hardening feature. If observed, this would imply that the sources could make good PeVatron candidates.
The Ultra-High-Energy Source MGRO J1908+06 Malone, Kelly; Abeysekara, Anushka Udara; Albert, Andrea ...
Pos : proceedings of science,
07/2021, Letnik:
395
Journal Article
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The TeV gamma-ray source MGRO J1908+06 is one of the highest-energy sources known, with observed emission by the High Altitude Water Cherenkov (HAWC) Observatory extending well past 100 TeV. The ...source exhibits both energy-dependent morphology and a spatially-dependent spectral index. The emission is likely to be dominantly leptonic, and associated with the radio-quiet PSR J1907+0602. However, one-population models do not describe the data well; a second particle population is needed to explain the shape of the spectral energy distribution at the highest energies. This component can be well-described by either leptonic or hadronic hypotheses. We discuss this feature and implications for detection by multi-wavelength and multi-messenger experiments.
Gammastrahlung von der Sonne Fleischhack, Henrike; Huentemeyer, Petra
Physik in unserer Zeit,
11/2023, Letnik:
54, Številka:
6
Journal Article
Die Sonne leuchtet im gesamten elektromagnetischen Spektrum. Erstmals gelang mithilfe von Daten des HAWC‐Observatoriums nun der Nachweis, dass die Sonne Photonen mit Energien bis in den TeV‐Bereich ...aussendet. Diese hochenergetischen Gammastrahlen sind intensiver, wenn sich die Sonnenaktivität in einem Minimum befindet. Theoretische Modelle können diesen Effekt noch nicht vollständig erklären.
Galaktische Protonenkanone Fleischhack, Henrike; Huentemeyer, Petra
Physik in unserer Zeit,
11/2022, Letnik:
53, Številka:
6
Journal Article
Schon lange wird nach Pevatronen gesucht, kosmischen Teilchenbeschleunigern, die subatomare Teilchen auf extreme Energien im Bereich von Petaelektronenvolt beschleunigen. Nun gelang der Nachweis, ...dass der Supernovaüberrest SNR G106.3+2.7 solch ein Pevatron enthält.
The charge collection properties of CVD diamond Behnke, Ties; Hüntemeyer, Petra; Oh, Alexander ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/1998, Letnik:
414, Številka:
2
Journal Article
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The charge collection properties of CVD diamond have been investigated with ionising radiation. In this study two CVD diamond samples, prepared with electrical contacts have been used as solid state ...ionisation chambers. The diamonds have been studied with beta particles and 10
keV photons, providing a uniform ionisation density and with protons and alpha particles which are absorbed in a thin surface layer. For the latter case a strong decrease of the signal as function of time is observed, which is attributed to polarisation effects inside the diamond. Spatially resolved measurements with protons show a large variation of the charge collection efficiency, whereas for photons and minimum ionising particles the response is much more uniform and in the order of 18%. These results indicate that the applicability of CVD diamond as a position sensitive particle detector depends on the ionisation type and appears to be promising for uniform ionisation densities as provided by relativistic charged particles.
Nucl.Instrum.Meth. A414 (1998) 340-356 The charge collection properties of CVD diamond have been investigated with
ionising radiation. In this study two CVD diamond samples, prepared with
electrical ...contacts have been used as solid state ionisation chambers. The
diamonds have been studied with beta particles and 10 keV photons, providing a
homogeneous ionisation density and with protons and alpha particles which are
absorbed in a thin surface layer. For the latter case a strong decrease of the
signal as function of time is observed, which is attributed to polarisation
effects inside the diamond. Spatially resolved measurements with protons show a
large variation of the charge collection efficiency, whereas for photons and
minimum ionising particles the response is much more uniform and in the order
of 18%. These results indicate that the applicability of CVD diamond as a
position sensitive particle detector depends on the ionisation type and appears
to be promising for homogeneous ionisation densities as provided by
relativistic charged particles.
The charge collection properties of CVD diamond have been investigated with ionising radiation. In this study two CVD diamond samples, prepared with electrical contacts have been used as solid state ...ionisation chambers. The diamonds have been studied with beta particles and 10 keV photons, providing a homogeneous ionisation density and with protons and alpha particles which are absorbed in a thin surface layer. For the latter case a strong decrease of the signal as function of time is observed, which is attributed to polarisation effects inside the diamond. Spatially resolved measurements with protons show a large variation of the charge collection efficiency, whereas for photons and minimum ionising particles the response is much more uniform and in the order of 18%. These results indicate that the applicability of CVD diamond as a position sensitive particle detector depends on the ionisation type and appears to be promising for homogeneous ionisation densities as provided by relativistic charged particles.
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