Energistyrning degree bending magnet S/H * PRF e- PRF Power amplifier Pulse transformer Computer * ADC program DAC High voltage Gun BBd/2008 1

Transkript

1 Energistyrning degree bending magnet S/H e - PRF * PRF Power amplifier Pulse transformer * ADC Computer program DAC High voltage Gun BBd/2008 1

2 Accelerator wave-guide Energistyrning 5 Gun Comparator Control Target Updown counter PROM DAC Ionisation chamber In modulator Thyratron Thyratron driver BBd/2008 2

3 Energy switch BBd/2008 3

4 BBd/2008 4

5 e - 90 Magnet Böjmagneter E 0 + E 270 E 0 E 0, E 0 ± E B N S E 0 - E E 0 E 0 + E e - E 0 - E Magnet Slalom Magnet E 0 + E e - E 0 - E Magnet Slits Target BBd/2008 5

6 90 -böjmagnet E 0, e - E 0 ± E B E 0 - E E 0 E 0 + E e - e - E 0 B E 0 B BBd/2008 6

7 Siemens 270 -böjmagnet BBd/2008 7

8 Slalom-böjkammare BBd/2008 8

9 Slalom-böjmagnet BBd/2008 9

10 Vad finns i strålhuvudet? BBd/

11 Strålhuvud; fotoner Bending magnet Accelerator wave-guide e - Bellow photons e - Bending chamber Electron window Primary collimator Target Primary scatter foil Filter Secondary scatter foils Ionisation chamber Wedge Mirror Lamp MLC MLC Collimators BBd/

12 Strålhuvud; elektroner Bending magnet Bending chamber Accelerator wave-guide e - Bellow photons e - Electron window Primary collimator Target Primary scatter foil Secondary scatter foils Filter Ionisation chamber Mirror Wedge Sänkt elektronström med en faktor ca 100 Lamp MLC MLC Collimators BBd/2008 Electron 12 applicator

13 Dålig effektivitet i target e - 0.5MV Target N Energispektrum Fotoner Elektroner γ 1MV 2MV E 5MV 8MV BBd/

14 Utjämningsfilter Target Avstånd Profiler på olika djup i patienten N N Avstånd i vatten Energi Energi BBd/

15 Filterkarusell BBd/

16 Scattering foil 1 Dubbla spridningsfolier Scattering foil 2 Treatment plane BBd/

17 Elektronapplikatorer Single scattering foil Diaphragms Double scattering foils a) b) BBd/

18 Skannande elektronstråle Scanning magnets Collimators BBd/

19 Jonisationskammare BBd/

20 Zero Dosimetrisystem - + Reference v Comparator Mono stable Counter v Figure 137.ppt Output voltage Digital comparator Set absorb Time dose register BBd/ Terminate radiation

21 Dosimetrisystem 300V Ionisation chamber 300V Monitoring In software Integrator and tracker Integrator and tracker Dummy dose-rate generator from software Control Status latches Control Dummy dose-rate generator from software Dose-rate Dose 1 and timer 1 in software Dose difference in software Dose 2 and timer 2 in software Dose-rate Excess dose-rate Air temperature and air Pressure compensation Excess dose-rate BBd/

22 Elektroner träffar target Primärkollimator Primärkollimator A B C D A B C D BBd/

23 Elektronbehandling N E Ytan av objektet Vid bendingmagneten Vid 2cm djup BBd/

24 Primärkollimering BBd/

25 Sekundärkollimering BBd/

26 Asymmetrisk kollimering och block Isocenter BBd/

27 Flerbladskollimator (MLC) BBd/

28 Flerbladskollimator (MLC) Monitor Control To leaf motors Video Target Light projector Mirror Video camera Mylar mirror Reflector Leaf Semi permeable mirror Mirror Patient plane Leaf motors BBd/

29 Flerbladskollimator (MLC) Monitor Flexible cables Multi- Frame plexer grabber Demultiplexer Video camera Leaf motors BBd/

30 Kil Physical Wedge Flying Wedge Dynamisk Wedge BBd/

31 Kil BBd/

32 Kompensatorer BBd/

33 Bildgivande system (EPID), film 6MV Rtg 25cm Luft Vatten Ben 100% 30% 25% BBd/

34 Jonisationskammare BBd/

35 Epid med fosforskärm och kamera BBd/

36 Indirekt detektering Elekta iview EPID Cablon Theraview Siemens Beamview Eliav PORTpro Direkt detektering BBd/

37 Panel från PerkinElmer Rtg - - Aluminium Luftgap Koppar Grafit Lanex Fast TM (Gd 2 O 2 S:Tb) Attenuator Fotodioder, amorft kisel BBd/ Jöns Jacob Berzelius

38 CT-system på acceleratorn BBd/

39 Elektas XVI-system BBd/

40 Intensitets Modulerad Radioterapi (IMRT) aspx... BBd/

41 Tomotherapy BBd/

42 BBd/

43 GammaKnife och CyberKnife BBd/

44 Enhanced dielectric-wall linear accelerator 09/22/1998 Document Type and Number: United States Patent Link to this page: Abstract: A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. BBd/

45 Dielectric Wall Accelerator Ett pulsat accelerationsfält bildas i asymmetriska Blumlein Korta pulser <10 ns och hög ström >1 ka. Användning av höggradientisolatorer. Mål: 250 MV på 2.5 m. BBd/

46 Vad är en transmissionsledning? i(z,t) koaxialkabel i(z+δz,t) ε Δz 0 Ekvivalent schema BBd/

47 Single line Högspänningskälla (V 0 ) Hur ser spänningen ut längs kabeln? l 2R 2R Om den karakteristiska impedansen Z 0 = R Slås till vid t=0 Spänning över kabeln V 0 V 0 V 0 V 0 t=0 l längd t=l/2ν p l t=l/2ν p l t=3l/2ν p l Utspänning V 0 /2 2l/ν p tid BBd/

48 Blumlein line l Högspänningskälla (V 0 ) Induktans ε ε ε ε Öppnar vid V 0 R V 0 Utspänning l/ν p 3l/ν p tid BBd/

49 Stackade Blumlein line 0 ε l l/ν p <t<3l/ν p V 0 0 V 0 0 ε ε ε ε 0 = 0 V 0 0 ε Kortslut vid t=0 t<0 t>3l/ν p BBd/

50 Symmetrisk Blumlein - t 1 t t t t ε ε ε ε ε ε ε ε ε ε V t 1 t 2 t 3 t 4 t 5 BBd/ t

51 Höggradientisolator (HGI) Överslag (elektriskt fält) 1000kV/cm HGI Motsvarande isolator 10 4 ns Pulsbredd BBd/

52 BBd/

53 Gitterstuktur Silicon Carbide (SiC) crystals BBd/

54 Silicon Carbide (SiC) crystals BBd/2008 /Caporaso et. 54 al.

55 Olika längd på ljusledarna => olika tillslagstider BBd/2008 /Caporaso et. 55 al.

56 BBd/

57 Fotoledande switch BBd/

58 Vakuum ytöverslag-switching di/dt >10 13 A/s 200kV Vakuum Laser Fotoledare eller elektronstråle inducerad solid-state switchar. Gaser under högt tryck och flytande dielektriska switchar BBd/

59 Jacqueline McBride/LLNL Above: Engineer John Harris prepares the vacuum test chamber used to subject high-gradient insulators (HGIs) to highvoltage electric fields. The HGI is the candidate dielectric wall material that will be used for the beam tube in LLNL?s compact proton-beam accelerator. Since it can sustain a very high electric field parallel to its surface, it will be able to provide a high accelerating gradient for the proton beam. Below: A time-integrated open-shutter photo of an HGI flashing over in a 150,000- to 200,000-volt-per-centimeter electric field. Elevating the flashover threshold of these insulators is key to the success of the project. BBd/

60 Proton-Tomotherapy In the Works: Compact, Low-cost Proton Therapy System It looks like proton therapy will be developed into a compact device, after a technology transfer agreement between Lawrence Livermore National Laboratory and TomoTherapy Inc., a Madison, Wisconsin company, was announced just a few days ago. The DWA, currently being built as a prototype at Livermore, can accelerate protons to up to 100 million electron volts in just a meter. A two-meter DWA could potentially supply protons of sufficiently high energy to treat all tumors, including those buried deep in the body, while fitting in a conventional radiation treatment room. medgadget.com/archives/nuclear_medicine BBd/

61 Intensity Modulated Proton Therapy (IMPT) BBd/

62 Fixed Field Alternating Gradient BBd/

63 Skillnader mellan olika fabrikat (konventionella linjäracceleratorer) Elekta Varian Siemens 1. Traveling Wave 2. Magnetron 3. Flying wedge 4. 3 fotonenergier 5. Slalom böjmagnet 6. MLC, 80 blad 7. MLC placerad ovanför kollimatorerna 8. Dubbla spridningsfolier 9. Diod-GUN 10.Modulator med tyratron 11.Step and shoot IMRT 12.MLC linjär rörelse 13.Starttid: ca 2 sek 14.Tillverkas i England 15.Ingen doshastighetsreglering 1. Standing Wave 2. Klystron 3. Dynamisk wedge 4. 2 fotonenergier böjmagnet 6. MLC, 120 blad 7. MLC placerad under kollimatorerna 8. Dubbla spridningsfolier 9. Triod-GUN 10.Modulator med tyratron 11.Sliding window IMRT 12.MLC linjär rörelse 13.Starttid: ca 200 ms 14.Tillverkas i USA 15.Lägger till PRF-pulser 1. Standing Wave 2. Magnetron, klystron 3. Dynamisk wedge 4. 2 fotonenergier böjmagnet 6. MLC, 82 blad 7. MLC placerad under kollimatorerna 8. Dubbla spridningsfolier 9. Diod-GUN 10.Kompakt modulator 11.Sliding window IMRT 12.MLC cirkulär rörelse 13.Starttid ca 200 ms 14.Tillverkas USA 15.Spänningsstyrd oscillator BBd/