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- Als Skyshine (engl. sky „Himmel“ und shine „Leuchten“) wird die von einer kerntechnischen oder nuklearmedizinischen Anlage ausgehende ionisierende Strahlung bezeichnet, die die Umgebung der Anlage nicht auf direktem Weg erreicht, sondern von der Atmosphäre auf die Erdoberfläche zurück reflektiert und gestreut wird. Dieser Effekt tritt auf, wenn die Abschirmung um die Strahlungsquelle nach oben offen ausgeführt ist. Im weiteren Sinn wird auch die im Inneren von kerntechnischen Anlagen etwa über die Hallendecke zurückgestreute Strahlung als Skyshine bezeichnet. Die Intensität der am Boden gemessenen Strahlung steigt dabei zunächst mit zunehmendem Abstand von der Abschirmung bis zu einem Maximum an und fällt danach kontinuierlich ab. Das Maximum tritt je nach Art der Strahlung in unterschiedlichen Abständen von der Strahlungsquelle auf. In Studien wurden z. B. für Röntgenstrahlung aus medizinischen Linearbeschleunigern Maxima bei 13,6 m für 18 MeV und bei 4,6 m für 6 MeV gemessen. Von 1967 bis 1975 kam es zu deutlichen Belastungen durch Skyshine auf dem und außerhalb des Geländes des Versuchsreaktors AVR Jülich, der keine Strahlenabschirmung nach oben besaß. 2011 erfuhr der Effekt im Rahmen der Diskussion um das Atommülllager Gorleben mediale Aufmerksamkeit, nachdem außerhalb der Anlage, deren Abschirmung u. a. als Schutzwall ausgeführt ist, erhöhte Strahlungswerte gemessen wurden. (de)
- (Radiation) skyshine describes the ionizing radiation emitted by a nuclear technical or medical facility, reaching the facility's surroundings not directly, but indirectly through reflection and scattering at the atmosphere back to earth's surface. This effect can happen when the shielding barrier around the source of radiation is open at the top. This effect can also happen when the shielding in the vault room of a linear particle accelerator in radiation therapy is not sufficient to reduce the intensity of the primary incident beam down to a very low level. For example, a member of the public may be positioned outside of such a room or vault in a nearby parking lot. For a radiation therapy facility with limited shielding in the vault ceiling, even if the radiation is directed straight upward through the ceiling into the atmosphere, there can still be a significant amount of radiation scattering off of the atmosphere backward and at an angle. This skyshine can be measured by a medical physicist at the position of the pedestrian standing on the ground in the nearby parking lot. Such radiation is generally measured in terms of exposure-rate or dose-rate. It has been shown that this downward intensity is heavily dependent on the shape of the beam. Regardless of whether the upward incident beam is shaped like a circle, square or rectangle, specific calculation formalism has been described. The intensity of radiation measured at the surface immediately surrounding the facility increases with growing distance from the shielding barrier to reach a maximum and then fall again continuously with further increasing distance. Depending on the energy of the scattering radiation, the intensity maximum is reached at different distances from the vault. For example, x-rays emitted from linear accelerators reached maxima of 18 MeV at a distance of 13.6 m and 6 MeV at 4.6 m in studies. Between 1967 and 1975 significant radiation damage of the surroundings was caused by radiation skyshine at and near the AVR reactor in Jülich, Germany, which, in its original BBC construction, lacked a top shielding barrier. In 2011, the skyshine effect reached media attention in the controversy around the radioactive waste repository after higher levels of radiation were measured outside the facility, despite it being shielded by a shielding wall. (en)
- L'effetto cielo skyshine descrive la radiazione ionizzante emessa da un centro di ricerca medico o nucleare, che raggiunge indirettamente l'area circostante a causa di riflessioni e diffusioni nell'atmosfera. Questo effetto si verifica solitamente quando la schermatura del tetto del centro di ricerca è assente o insufficiente. In senso lato, con skyshine si descrive anche la radiazione riflessa dal soffitto all'interno di un centro di ricerca nucleare. Nelle immediate vicinanze del centro di ricerca, l'intensità della radiazione misurata aumenta con la distanza dalla schermatura fino a raggiungere un massimo da cui decresce quindi con continuità. Il punto di intensità massima è raggiunto a varie distanze dalla sorgente, in base al tipo di radiazione. Per esempio: per dei raggi x di 18 MeV emessi dagli acceleratori lineari, il massimo si raggiunge a 13.6 m; questa distanza si riduce a 4.6 m se l'energia è di 6 MeV. Schema di un originariamente senza tetto schermato Tra il 1967 e il 1975 l'area circostante il di Jülich, in Germania, fu colpita da ingenti a causa dell'effetto skyshine. In base a quanto riportato dalla BBC, questo avvenne a causa della mancanza di un tetto schermato. (it)
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- Als Skyshine (engl. sky „Himmel“ und shine „Leuchten“) wird die von einer kerntechnischen oder nuklearmedizinischen Anlage ausgehende ionisierende Strahlung bezeichnet, die die Umgebung der Anlage nicht auf direktem Weg erreicht, sondern von der Atmosphäre auf die Erdoberfläche zurück reflektiert und gestreut wird. Dieser Effekt tritt auf, wenn die Abschirmung um die Strahlungsquelle nach oben offen ausgeführt ist. Im weiteren Sinn wird auch die im Inneren von kerntechnischen Anlagen etwa über die Hallendecke zurückgestreute Strahlung als Skyshine bezeichnet. (de)
- (Radiation) skyshine describes the ionizing radiation emitted by a nuclear technical or medical facility, reaching the facility's surroundings not directly, but indirectly through reflection and scattering at the atmosphere back to earth's surface. This effect can happen when the shielding barrier around the source of radiation is open at the top. This effect can also happen when the shielding in the vault room of a linear particle accelerator in radiation therapy is not sufficient to reduce the intensity of the primary incident beam down to a very low level. For example, a member of the public may be positioned outside of such a room or vault in a nearby parking lot. For a radiation therapy facility with limited shielding in the vault ceiling, even if the radiation is directed straight up (en)
- L'effetto cielo skyshine descrive la radiazione ionizzante emessa da un centro di ricerca medico o nucleare, che raggiunge indirettamente l'area circostante a causa di riflessioni e diffusioni nell'atmosfera. Questo effetto si verifica solitamente quando la schermatura del tetto del centro di ricerca è assente o insufficiente. In senso lato, con skyshine si descrive anche la radiazione riflessa dal soffitto all'interno di un centro di ricerca nucleare. Schema di un originariamente senza tetto schermato (it)
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- Skyshine (de)
- Effetto cielo skyshine (it)
- Skyshine (en)
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