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PL
Audyty dozymetryczne są niezbędnym elementem zapewnienia spójności dozymetrycznej i bezpiecznej radioterapii. Audyt dozymetrii referencyjnej dla wiązek radioterapeutycznych jest częścią kompletnego systemu zapewnienia jakości. W 1991 roku IPSM utworzyło regionalne grupy audytowe, dzieląc Wielką Brytanię na osiem regionów geograficznych. Grupy te przeprowadzają audyty między zrzeszonymi ośrodkami co roku i ad hoc na żądanie w przypadku nowo zainstalowanego systemu radioterapii, systemu planowania leczenia, nowej techniki i modeli obliczeniowych. W 1994 roku IPEM zaprosił NPL do przeprowadzenia niezależnych audytów, które miały stanowić powiązanie z pierwotnym wzorcem metrologicznym dla dawki, początkowo przeprowadzając jeden audyt dozymetrii fotonów MV na region rocznie, a później rozszerzono go o audyty dozymetrii referencyjnej elektronów oraz kV. Obecnie dotyczy to również technik specjalnych, takich jak SABR w przypadku leczenia nowotworów płuca, SRS dla leczenia nowotworów kręgosłupa i mózgowia.
EN
Audit is imperative in delivering consistent and safe radiotherapy. Audit of reference dosimetry for radiotherapy beams forms part of a complete quality assurance system. In 1991 the IPSM formed regional audit groups, dividing the UK into eight geographical regions. These groups conduct audits between the associated centres on an annual basis and ad hoc when requested for the new installed raditherapy system, tretament planning system, new technique and calculation models. In 1994, NPL was invited by IPEM to provide independent audits to act as a link to the primary standard, initially performing one MV photon dosimetry audit per region per year and later expanded to include electron and kV reference dosimetry audits. Currently it is also escaleted to special techniques like i.e SABR fro lung, spine and intracranial SRS for spine.
PL
W artykule przybliżono problematykę kriomodułów, urządzeń stosowanych w akceleratorach cząstek naładowanych. Podkreślono znaczenie wykorzystania materiałów nadprzewodnikowych w ich konstrukcji i zalety takich rozwiązań. Usystematyzowano specyfikę występujących tu zagadnień i wskazano przykłady zastosowania.
EN
The article presents the subject of cryomodules, devices employed in charged particle accelerators. The authors emphasize the importance of using superconducting materials in the construction of cryomodules and the advantages of such a solution. A systematic approach to the specific problems is presented and supported by the examples of application.
EN
The paper reports results of the recent experimental studies of pulsed electron beams and soft X-rays in plasma-focus (PF) experiments carried out within a modifi ed PF-360U facility at the NCBJ, Poland. Particular attention was focused on time-resolved measurements of the fast electron beams by means of two different magnetic analyzers, which could record electrons of energy ranging from about 41 keV to about 715 keV in several (6 or 8) measuring channels. For discharges performed with the pure deuterium fi lling, many strong electron signals were recorded in all the measuring channels. Those signals were well correlated with the fi rst hard X-ray pulse detected by an external scintillation neutron-counter. In some of the analyzer channels, electron spikes (lasting about dozens of nanoseconds) and appearing in different instants after the current peculiarity (so-called current dip) were also recorded. For several discharges, fast ion beams, which were emitted along the z-axis and recorded with nuclear track detectors, were also investigated. Those measurements confi rmed a multibeam character of the ion emission. The time-integrated soft X-ray images, which were taken side-on by means of a pinhole camera and sensitive X-ray fi lms, showed the appearance of some fi lamentary structures and so-called hot spots. The application of small amounts of admixtures of different heavy noble gases, i.e. of argon (4.8% volumetric), krypton (1.6% volumetric), or xenon (0.8% volumetric), decreased intensity of the recorded electron beams, but increased intensity of the soft X-ray emission and showed more distinct and numerous hot spots. The recorded electron spikes have been explained as signals produced by quasi-mono-energetic microbeams emitted from tiny sources (probably plasma diodes), which can be formed near the observed hot spots.
EN
The most powerful now in the world, American X-ray laser LCLS (Linac Coherent Light Source), has been working as a research and user facility since 2009. It is further developed to LCLS II machine at the Stanford National Accelerator Laboratory SLAC in Menlo Park CA. In a certain sense, LCLS II is a response to the EXFEL machine and a logical extension of LCLS. All these machines are light sources of the fifth generation. EXFEL is expected to open user facility in 2016, at a cost of over 1 mld Euro. LCLS II, which design started in 2010, will be operational in 2017. The lasers LCLS, LCLS II and EXFEL use SASE and SEED methods to generate light and are powered by electron linacs, LCLS by a warm one, and EXFEL by a cold one. The linacs have energies approaching 20 GeV, and are around 2 - 3 km in length. EXFEL linac uses SRF TESLA microwave cavity technology at 1,3 GHz. A prototype of EXFEL was FLASH laser. SLAC Laboratory uses effectively over 50 years experience in research, building and exploitation of linear electron accelerators. In 2009, a part of the largest 3 km SLAC linac was used to build the LCLS machine. For the LCLS II machine a new infrastructure is build for two new laser beams and a number of experimental stations. A number of experts and young researchers from Poland participate in the design, construction and research of the biggest world linear and elliptical accelerators and FEL lasers like LCLS (Stanford), EXFEL (DESY) and CEBAF (JLab), and a few more. The paper concentrates on the development state-of-the-art of large laser infrastructure and its global and local impact, in the competitive world of R&D. LCLS infrastructure implications in Poland are considered.
EN
ILC machine–International Liner Collider, is one of two accelerators e+e-just under design and advanced consideration to be built with final energy of colliding electron and positron beams over 1 TeV. An alternative project to ILC is CLIC in CERN The ILC machine is an important complementary addition for the research potential of the LHC accelerator complex. The required length of ILC is minimally 30 km, but some versions of the TDR estimates mention nearly 50km. Superconducting RF linacs will be built using well established 1,3 GHz TESLA technology using ultrapure niobium or Nb3Sn resonant microwave cavities of RRR class, of ultimate finesse, working with gradients over 35MV/m, while some versions of the design mention ultimate confinement as high as 50MV/m. Several teams from Poland (Kraków. Warszawa, Wrocław – IFJ-PAN, AGH, UJ, NCBJ, UW, PW, PWr, INT-PAN) participate in the global design effort for this machine – including detectors, cryogenics, and SRF systems. Now it seems that the ILC machine will be built in Japan, during the period of 2016-2026. If true, Japan will turn to a world super-power in accelerator technology no.3 after CERN and USA. The paper summarizes the state-of-the-art of technical and administration activities around the immense ILC and CLIC machines, with emphasis on potential participation of Polish teams in the global effort of newly established LCC –The Linear Collider Consortium.
PL
Najpotężniejszy obecnie na świecie, Amerykański Laser Rentgenowski LCLS (Liniac Coherent Ligt Source), czyli liniakowe koherentne źródło światła, działa od roku 2009, jako urządzenie badawcze i użytkowe, i jest dalej rozwijane do postaci LCLS II na terenie narodowego Amerykańskiego laboratorium SLAC przy uniwersytecie Stanforda, zlokalizowanego w miejscowości Menlo Park w Kalifornii. W pewnym sensie LCLS II jest odpowiedzią na budowę maszyny EXFEL. Jest to źródło światła piątej generacji. Przewiduje się uruchomienie EXFEL w latach 2015/16, kosztem znacznie ponad 1 mid Euro. LCLS II, którego projekt rozpoczął się w 2010, będzie uruchomiony w roku 2017. Lasery LCLS, LCLS II oraz EXFEL, wykorzystują metody SASE oraz SEED do generacji światła, i są zasilane liniakami elektronowymi, LCLS ciepłym a EXFEL zimnym, o energii kilkanaście GeV i długości ponad 2 km. Liniak EXFEL wykorzystuje technologię nadprzewodzącą SRF TESLA o częstotliwości 1,3 GHz. Prototypem maszyny EXFEL jest laser FLASH. Laboratorium SLAC korzysta z ponad 50-letniego doświadczenia budowy i eksploatacji liniowych akceleratorów elektronowych. W roku 2009 fragment największego, 3 km elektronowego akceleratora liniowego SLAC został wykorzystany do budowy maszyny LCLS. Dla maszyny LCLS II budowana jest nowa infrastruktura dla dwóch nowych wiązek laserowych. W badaniach i budowie największych światowych akceleratorów liniowych i pierścieniowych oraz laserów FEL takich jak LCLS (Stanford), EXFEL (DESY) i CEBAF (JLab) biorą udział specjaliści i młodzi uczeni z Polski.
EN
The most powerful now in the world, American X-ray laser LCLS (Linac Coherent Light Source), has been working as a research and user facility since 2009. It is further developed to LCLSII machine at the Stanford National Accelerator Laboratory SLAC in Menlo Park CA. In a certain sense, LCLS is a response to the EXFEL machine and a logical extension of LCLS. All these machines are light sources of the fifth generation. EXFE-Lis expected to open user facility in 2016, at a cost of over 1 bil Euro. LCLS II, which design started in 2010, will be operational in 2017. The lasers LCLS, LCLS II and EXFEL use SASE and SEED methods to generate light and are powered by electron liniacs, LCLS by a wrm one, and EXFEL by a cold one. The liniacs have energies approaching 20 GeV, and are around 2 - 3 km in length. EXFEL liniac uses SRF TESLA cavity technology at 1,3GHz. A prototype of EXFEL was FLASH laser. SLAC Laboratory uses effectively over 50-years experience in research, building and exploitation of linear electron accelerators. In 2009, a part of the largest 3 km SLAC liniac was used to build the LCLS machine. For the LCLS II machine a new infrastructure is build for two new laser beams and a number of experimental stations. A number of experts and young researchers from Poland participate in the design, construction and research of the biggest world linear and elliptical accelerators and FEL lasers like LCLS (Stanford), EXFEL (DESY) and CEBAF (JLab), and a few more.
PL
Europejski Laser Rentgenowski EXFEL jest budowany na terenie laboratorium Niemieckiego Synchrotronu Elektronowego DESY w Hamburgu. Przewiduje się jego uruchomienie w latach 2015/16, kosztem ponad 1 mld Euro. Laser, wykorzystujący metodę SASE, zasilany jest liniakiem elektronowym o energii 17,5 GeV i długości ponad 2 km. Liniak wykorzystuje technologię nadprzewodzącą SRF TESLA o częstotliwości 1,3 GHz. Prototypem maszyny EXFEL jest laser FLASH (o długości ok. 200 m), gdzie sprawdzono "proof of principle" i technologie transferowane do większej maszyny. Projekt rozpoczęto w latach dziewięćdziesiątych budową w DESY laboratorium TTF – Tesla Test Facility. Laser EXFEL jest pokłosiem większego (obecnie zarzuconego w Niemczech a podjętego przez środowisko międzynarodowe w postaci projektu ILC) projektu budowy wielkiego zderzacza teraelektronowoltowego TESLA. W budowie i badaniach laserów FLASH i EXFEL biorą udział specjaliści i młodzi uczeni z Polski.
EN
European X-Ray FEL - free electron laser is under construction in DESY Hamburg. It is scheduled to be operational at 2015/16 at a cost more than 1 billion Euro. The laser uses SASE method to generate x-ray light. It is propelled by an electron linac of 17,5 GeV energy and more than 2 km in length. The linac uses superconducting SRF TESLA technology working at 1,3 GHz in freguency. The prototype of EXFEL is FLASH Laser (200 m in length), where the "proof of principle" was checked, and from the technologies were transferred to the bigger machine. The project was started in the nineties by building a TTF Laboratory -Tesla Test Facility. The EXFEL laser is a child of a much bigger teraelectronovolt collider project TESLA (now abandoned in Germany but undertaken by international community in a form the ILC). A number of experts and young researchers from Poland participate in the design, construction and research of the FLASH and EXFEL lasers.
PL
TIARA jest Europejskim Konsorcjum Techniki Akceleratorowej, które poprzez prowadzenie projektów badawczych, technicznych, sieciowych i infrastrukturalnych ma doprowadzić do integracji środowiska naukowo-technicznego oraz zasobów materialnych w skali całej Europy. Konsorcjum gromadzi wszystkie ośrodki europejskie posiadające dużą infrastrukturę akceleratorową. Pozostałe ośrodki, jak np. uniwersytety, są afiliowane jako członkowie stowarzyszeni. TIARA-PP (faza przygotowawcza) jest projektem europejskim prowadzonym przez Konsorcjum i wykonywanym w ramach EU FP7. W artykule przedstawiono ogólny zakres działań Konsorcjum TIARA, poprzedzając to portretem współczesnej techniki akceleratorowej oraz przeglądem jej zastosowań w nowoczesnym społeczeństwie.
EN
TIARA is an European Collaboration of Accelerator Technology, which by running research projects, technical, networks and infrastructural has a duty to integrate the research and technical communities and infrastructures in the global scale of Europe. The Collaboration gathers all research centers with large accelerator infrastructures. Other ones, like universities, are affiliated as associate members. TIARA-PP (preparatory phase) is an European infrastructural project run by this Consortium and realized inside EU-FP7. The paper presents a general overview of TIARA activities, with an introduction containing a portrait of contemporary accelerator technology and a digest of its applications in modern society.
EN
The Monte Carlo (MC) simulation of radiation transport is considered to be one of the most accurate methods of radiation therapy dose calculation. With the rapid development of computer technology, MC-based treatment planning for radiation therapy is becoming practical. A basic requirement for MC treatment planning is a detailed knowledge of radiation beams of medical linear accelerators (linacs). A practical approach to acquire this knowledge is to perform MC simulation of radiation transport for linacs. The aims of this study were: modeling of the electron beams from the NEPTUN 10PC linear accelerator (linac) with the MC method, obtaining of the energy spectra of electron beams, and providing the phase-space files for the electron beams of this linac at different field sizes. Electron beams produced by the linac were modeled using the BEAMnrc MC system. Central axis depth-dose curves and dose profiles of the electron beams were measured experimentally and also calculated with the MC system for different field sizes and energies. In order to benchmark the simulated models, the percent depth dose (PDD) and dose-profile curves calculated with the MC system were compared with those measured experimentally with diode detectors in an RFA 300 water phantom. The results of this study showed that the PDD and dose-profile curves calculated by the MC system using the phase-space data files matched well with the measured values. This study demonstrates that the MC phase-space data files can be used to generate accurate MC dose distributions for electron beams from NEPTUN 10PC medical linac.
PL
Przedstawiono podstawowe zjawiska towarzyszące oddziaływaniu wiązki elektronów (WE) z materiałem i mechanizm powstawania spoiny. Pokazano najważniejsze zespoły urządzenia do spawania WE i omówiono ich działanie i parametry.
EN
The phenomena accompanying of EB-material interaction and the mechanism of EB weld creation were presented. The most important units of the welding machines were shown and their principle of working and parameters were described.
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