9MeV电子直线加速器X射线测量Ξ

166Vol.16,No.620046HIGHPOWERLASERANDPARTICLEBEAMSJun.,2004:100124322(2004)06208052049MeVXX,,,,,,(,621900):CT9MeV,XXXCT;XX,9MeVCT:Farmer;LiF;;X:O571.436;TL53:A9MeVCT,9MeVX,,[1]:Im0.2A;m4s;fm50250HzX9MeV,1m77.4C/kgX80%;X,0.1%11.1X,,0.6cm3Farmer,Unidos,20m,46MV,68MV,810MV30keV50MeV,0.14ms,5.0Gy/s(99.5%)10Gy/s(99%),0.46mGy(99.5%)0.91mGy(99%),130kV,810MV(17.8mm)(68MV)138145kV-1.5483.096nC/(kgs),138145kV,24.768nC/(kgs),01258C/(kgs)1.2LiFLiF,,LiF,654TLDLiFLiF,LiFs15%s23%,654TLD0.3%,ss=s21+s22=5.9%(1)Cs137,1LiFX:2003210216;:2004202210::(1968),,,,,;91921014©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.Fig.1ExposureresponseofLiF1LiF,10312C/kg26132mC/kg,X2X1X2=0.989X1(2)LiF4mm4mm0.8mmLiF17mm()9LiF,138145kV,3mLiF(,),2[2],DK,DK(3)K,K,LiF;,X,LiF2,138kV,1517mm,LiF;145kV,1618mm,LiF,17mm,DXD33.97X(4):DGy,XC/kgFig.2AbsorptioncurvesofPMMAforXraysfrom9MeVlinearelectronaccelerator29MeVX29MeVX2.11m145kV,100Hz,1mX8.77mC/(kgs),87.72C/kg(50250Hz),145kV,LiF1m108,X9.75mC/kg,90.3C/kg2.23ÛXL,1m,1m1/L2,ÛX(L)=34.021L-2ÛX1m2.3X9MeVXXd0,5.0,7.5,12.5cm,X,4X/X0=0.994e-0.104d(5)60816©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.Xeff0.104cm-1,(eff/)0.039gcm-2,[3][4]X2.6218MeVXX1/3,X7.8814MeV2.41m,1mX51m144kV(a)LiF1m-7+7,-3.5+3.580%;,5,(b)1m015;[5](6)8.02MeV,X=X0exp[-(E+0.5)/120](6):E,MeV;,()Fig.3Inrightfrontoftheanodetarget,therelationbetweenexposureanddistance3Fig.4AbsorptionofAlforXraysfrom9MeVlinearelectronaccelerator49MeVXFig.5Angledistributionsofexposureat1minfrontoftheanodetarget51m2.5,1mX,6,1m61m66mm,80%18mm,3%18mm2.6,X0.1%X,,X,,,,2.5cm,5cm0.1%7086:9MeVX©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.Fig.6Transversedistributionsofexposureat1minfrontoftheanodetargetaftercollimation6,1mX,(),,,,,,1.40mm[6]3X,9MeVCTVanianCTLinatron23000AX9MeV,1m774mC/kgmin9MeVX8.02MeV,1m877.2mC/kgmin(200Hz),,,X9MeV,,200Hz,,,,,1m,,,200Hz:[1].[M].:,1985.133.(ZhangHC.Applicationoflow2energyaccelerator.Beijing:ChinaMechinePress,1985.133)[2].[M].:,1981.40.(LiSJ.Ionizationradiationdosimetry.Beijing:AtomicEnergyPress,1981.40)[3]FH,WC,,.()[M].:,1981.118.(AttixFH,RoeschWC,ShiXQ,etal.Radiationdosimetry(vol.)frndamental(inChinese).Beijing:AtomicEnergyPress,1981.118)[4].[M].:,1983.211.(JiangM.Introductionofnucleonics.Beijing:AtomicEnergyPress,1981.118)[5].CAEPX[A]..[C].:,1995.84.(TaoZC.DevelopmentofflashX2raymachinesatCAEP.LiuXS.ThedecadeselectedworksofhighpulsedpowerinChina.SichuanMianyang:TheA2cademyofParticleAcceleratorinChina,1995.84)[6],,,.CTX[J].,2004,16(3):390394.(ChenH,XuZ,JinX,etal.MeasurementofnewtypeX2raysource.HighPowerLaserandParticleBeams,2004,16(3):390394)X2raydosimetryof9MeVLINACPANQing,HUHe2ping,CHENHao,LIUXi2san,LIMing,JINXiao,XUZhou(InstituteofAppliedElectronics,CAEP,P.O.Box91921014,Mianyang621900,China)Abstract:IndustrialCTadoptselectronacceleratortoproducethehighenergyX2raybremsstrahlung,andmakesuseoftheprin2cipleofdifferentabsorptioncoefficientandscatteringcoefficientwhentheX2raycutsthroughdifferentmaterialstochecktheinternalblemishorinternalstructureofthematerial.ThequantityandthespeedofcreatingimageoftheindustrialCTcloselyrelatetotheaccel2eratorsfocus,thehighestX2rayenergy,Xraysdoseanddoseuniformity.ProtectingtheelectronicscircuitofthedetectoragainstX2rayrelatetothedetectorsservicelife.TheXraysmeasuringresultsgiveninthisarticleshowthatthe9MeVLINACcansatisfiethere2quirementsforcheckingthematerialstructureandblemishbythehighenergyindustrialCT.Keyword:Farmerchamber;LiFthermoluminescentdosemeter;LINAC;DoseofX2ray80816©1995-2005TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.