摘要:
A method of spectrometric photon dosimetry for integrally and nuclide-specifically determining a gamma dose rate for X-ray and gamma radiation. The method includes measuring a spectrum in at least one energy group or at least one interval group. The pulse height distribution is with a spectrometer and a pulse height analyzer. The number of channels of the spectrometer is such that a map of the pulse height distribution at a requisite resolution over an energy can be made. The measured pulse height distribution is converted into a photon spectrum using a deconvolution procedure that uses response functions having the same energy resolution as the pulse height distribution. The dose spectrum is calculated using dose conversion factors that are energy-dependent and related to the mean energy of a respective corresponding energy interval. The integral dose or dose rate is determined by summing the dose spectrum. The spectrometer is switched to a low-resolution mode of operation in order to ascertain an integral dose rate and switched to a high-resolution mode of operation in order to analyze radiation sources for which nuclides that cause higher dose rates are to be identified.
摘要:
A radiation shielding arrangement for shielding high-energy neutron radiation and gamma radiation from high-energy particle accelerators or storage rings includes a shielding element made of water-containing material, for example with chemically bound water or water of crystallization, in particular gypsum. The water component of the material preferably makes up at least 5, 10 or 20 percent by weight. The hydrogen nuclei or protons contained therein moderate neutrons in a virtually ideal manner because of the almost identical mass and the maximum pulse transformation associated with this.
摘要:
An area dosimeter for measuring the ambient equivalent dose of photon radiation with a diffuser, and a detector card with at least one pair of detection elements, preferably LiF-chips. A first of the two detection elements is positioned between two filters in order to spectrally filter the photon radiation. A second of the two detection elements is not positioned between such filters in order that the photon radiation arriving at the second detection element will have a different spectral distribution from the spectrally filtered photon radiation arriving at the first detection element. The two measurement values are used to obtain a weighted sum in order to achieve an optimized response characteristic.
摘要:
A dosimeter for detecting high-energy neutron radiation having a neutron converter and a detection element is proposed which is characterized by the neutron converter comprising metal atoms which convert the energy of the neutrons into protons, alpha particles and other charged nuclei in a suitable energy range so that they are detectable.
摘要:
The invention consists of an area dosimeter for measuring the ambient equivalent dose (H*(10)) of photon radiation with a diffuser, a detector card with at least one pair of detection elements, preferably LiF-chips, whereby the first of the two detection elements is positioned between two filters in order to spectrally filter the photon radiation, whereby the second of the two detection elements is not positioned between such filters as those of the first detection element, in order that the photon radiation arriving at the second detection element have a different spectral distribution as the spectrally filtered photon radiation arriving at the first detection element. The two measurement values are used to obtain a weighted sum in order to achieve an optimized response characteristic, in particular in the range below 30 keV and if applicable in the range above 1.3 MeV.
摘要:
A method of spectrometric photon dosimetry for integrally and nuclide-specifically determining a gamma dose rate for X-ray and gamma radiation. The method includes measuring a spectrum in at least one energy group or at least one interval group. The pulse height distribution is with a spectrometer and a pulse height analyzer. The number of channels of the spectrometer is such that a map of the pulse height distribution at a requisite resolution over an energy can be made. The measured pulse height distribution is converted into a photon spectrum using a deconvolution procedure that uses response functions having the same energy resolution as the pulse height distribution. The dose spectrum is calculated using dose conversion factors that are energy-dependent and related to the mean energy of a respective corresponding energy interval. The integral dose or dose rate is determined by summing the dose spectrum. The spectrometer is switched to a low-resolution mode of operation in order to ascertain an integral dose rate and switched to a high-resolution mode of operation in order to analyze radiation sources for which nuclides that cause higher dose rates are to be identified.
摘要:
Disclosed is a dosimeter (1) for the detection of neutron radiation within an energy range of 0.025 eV to several hundred GeV, comprising a substantially spherical base body (3) which is used as a moderation body and which comprises hydrogenous material, a detection element (5) which is arranged in the center of the base body (3), and a neutron converter (7) surrounding the detection element (5). The neutron converter (7) comprises metal atoms which convert the energy of the high-energy neutron radiation essentially into neutrons within a suitable energy range. The dosimeter (1) is characterized in that the base body (3) is provided with an access (19) through which the detection element (5) can be introduced into the neutron converter (7) and removed therefrom, and in that the neutron converter (7) is embodied in the form of a cylinder.
摘要:
The invention relates to a multi-layered radiation protection wall for shielding against the gamma and/or the particle radiation of a reaction site on an accelerator facility, wherein the radiation protection wall comprises a sandwich-like structure with at least a first and a second layer arrangement, wherein the first layer arrangement has at least a primary shielding layer and the second layer arrangement has at least a secondary shielding layer.Thereby, at least one of the first and the second layer arrangement is sub-divided into a plurality of partial sections, whereby a selected disposal is made possible. Thus an increased cost efficiency is achieved and the environmental impact is lowered.
摘要:
In a shielded chamber for neutron therapy including a therapy room which has a main axis as determined by the direction of a high-energy neutron therapy beam surrounded by shielding and includes at one end a labyrinth entrance with at least two shielding wall sections displaced longitudinally along the main axis and extending into the room from opposite side walls, the wall sections include means for causing spallation of the incident high energy neutrons to thereby generate from the high energy neutrons in the high energy neutron beam a plurality of low energy neutrons which are then moderated.
摘要:
Irradiation device for proton and/or ion beam therapy, said device comprising a radiation source, a beam guiding device, and a therapy room comprising a treatment site and an access, wherein the therapy room is arranged in a first plane, and the treatment beam is directed into the therapy room from a second plane above or below the first plane, and oriented towards the treatment site so that the treatment beam is directed away from the access. In the therapy room, a shielding is provided, which is open towards the treatment site and associated with the entrance region of the treatment beam into the therapy room so that the access is arranged on the side of the shielding opposing the treatment site, and a labyrinth leading from the access to the treatment site is provided laterally offset to the treatment beam proceeding in the therapy room and to the shielding.