DAI HOC QUOC GIA HA NOI TRLTCJNG DAI HOC KHOA HOC TI/ NHIEN TEN DE TAI NGHIEN ClTU MOT SO DAC TRlTNG CUA CO CHE SINHBlTC XA HAM VA NOTRON TREN MAY GIA TOG ELECTRON VA MOT SO ITNG DUNG MA SO: QG-07-06 Chu nhiem de tai: TS Bui Van Loat Cac can bo tham gia: CN Vu Thanh Mai -Truang Dai hoc Khoa hoc Tu nhien, DHQGHN CN Tran The Anh - Truang Dai hoc Khoa hoc Tu nhien, DHQGHN CN Phung Thi Nguyet Sinh vien K49 nganh Vat ly, Truang DHKHTN CN Nguyen Tiln Quan, SV K49 nganh CNHN, Truang DHKHTN TS Pham Due Khue- Vien Vat ly, Vien Khoa hoc va Cong nghe Viet Nam r ThS Kim Tien Thanh- Vien Vat ly, Vien Khoa hoc & Cong nghe Viet Nam TS Nguyen Quang Mien- Vien Khao c6 hoc Viet Nam ThS Hoang Hun Due- Vien H6a hoc Quan sir ThS Ngu>'cn Xuan KOr- Benh vien K CN Nguyen Thi Thanh Tarn- Truang THPT Tran Hung Dao Ha Noi HaNoi, 2008 BAO CAO TOM TAT a Ten de tai Tilng Viet: Nghien cuu mot so dac trimg ciia ca che sinh biic xa ham va natron tren may gia toe electron va mot so ung dung Tilng Anh: Study of the characteristics of bremsstrahlung photons and neutrons on the electron accelerator and applications Ma s6: QG-07-06 b Chu tri dk tai: TS Bui Van Loat c Can bg tham gia: CN Vu Thanh Mai CN Tr4n Thi Anh CN Nguyen Thj Thanh Tam SV Nguyen Tien Quan SV Phung Thi Nguyet TS Pham Due Khue ThS Kim Tien Thanh TS Nguyen Quang Mien ThS Nguyin Xuan Ku ThS Hoang Huu Due d Muc tieu va noi dung nghien cuu: Muc tieu ciia De tai la nghien cuu dac trung ca ban nhu nang lugng, phan bo thong lugng ciia buc xa ham va natron sinh tren may gia toe electron - Nghien cuu tong quan ve ca che sinh buc xa ham va natron electron tuang tac vai vat chat sinh -Ket hgp giua tinh toan ly thuyet theo phuang phap mo phong Monte- Carlo va phuang phap thuc nghiem xac dinh mot so dac trung ciia buc xa ham: + Phan bo theo goc ciia thong lugng chum buc xa ham nang lugng cue dai 15MeVva65MeV + Phan b6 cua buc xa ham theo khoang each tinh tu bia + Ph6 nang lugng cua buc xa ham + Phan bo ciia natron theo be day bia Ta,W - Mot s6 ung dung nghien cuu so lieu hat nhan va phan tich kich boat, e Ket qua chinh cua de tai V€ mat ly thuyet: - Da tim hieu ca che sinh buc xa ham va natron electron nang lugng cao tuang tac vai hat nhan nang - Tim hieu dac trung ciia phan ung quang hat nhan duai tac dung ciia chum photon nang lugng cao - Tim hieu phuang phap va ky thuat thuc nghiem phan tich gamma, phuang phap hieu chinh nang cao chinh xac ciia phep Ve mat thuc nghiem: - Sir dung cac phan ung quang hat nhan c6 nguang de xac dinh thong lugng vi phan ciia chum buc xa ham nang lugng cue dai 15 MeV phat tir bia W mong Bang phuang phap mo phong Monte - Carlo vai chuong trinh mo phong ESG4, tinh toan ly thuyet ciia buc xa ham phat electron nang lugng 15MeV tuang tac vai bia W Pho buc xa ham thu dugc bang each lam khop tinh toan tu ly thuyet vai vi phan thu dugc tu thuc nghiem - Thong qua viec xac djnh suat lugng phan ung quang hat nhan ^^''Auiy.n)^'^^An da khao sat phan bo theo goc ciia chum buc xa ham nang lugng cue dai 15MeV, 65 MeV phat tir bia W dang la mong Ket qua thuc nghiem chi rang cac buc xa ham bay theo huang iru tien ve phia truac - Bang thiet bj lieu true tiep va gian tiep da xac dinh su suy giam cua thong lugng chum buc xa ham nang lugng 15 MeV tu may gia toe electron diing xa tri tai Benh vien K theo khoang each tai bia - Bang phuang phap kich boat phong xa cac foil ^''AI va '^''AU dat tai cac vi tri khac cua bia da xac dinh dugc phan bo thong lugng cua natron sinh theo be day bia Vai chum electron nana luona 65 MeV doi vai Pb thong lugng natron nhiet dat gia tri cue dai ca 2,0 cm thong lugng natron nhanh cue dai be day bia ca 0,7 cm Doi vai Ta thong lugng natron nhiet dat gia tri cue dai ca 1cm - Xac dinh ti so tiet dien dong phan ciia phan ung "^^Fe(y,xnp)^^'^'^Mn vai chum buc xa ham c6 nang lugng cue dai 50 MeV, 60MeV va 70 MeV Kit qua dao tao + Da huang dan 03 khoa luan tot nghiep: Nguyen Tien Quan, K49 nganh Cong nghe Hat nhan: Xac dinh bang thuc nghiem dac trung phan bo goc ciia buc xa ham nang lugng cue dai 15 MeV va 65MeV Tran The Anh, K49 chuyen nganh Vat ly hat nhan: Xac djnh bang thuc nghiem phan bo thong lugng ciia natron theo be day bia Pb ban pha chum electron 65 MeV Phung Thj Nguyet, K49 chuyen nganh Vat ly hat nhan: Xac dinh ty so Isomer cua phan img ""' Pe (/,jc;?i/?)"""•' Mn vai chum buc xa ham nang lugng cue dai 70MeV + Ten cao hoc va de tai luan van thac sT da bao ve cone: • • • • o Nguyen Hun Duc-Khoa 2005-2007 ''Xac dinh suat luang cua phan ung "' All (/,jrA7)"' Au vai chiim buc xa ham nang lugng cue dai 65MeV'\ Nguyen Thi Thanh Tam- Khoa 2006-2008 ''Xac dinh ty so Isomer cua phan img ""' Pe (y,xn\p)-^""' Mn vai chum buc xa ham nang lugng cue dai 50MeV,60MeV va 70MeV + Co 03 bao cao va bai bao: Determination of the annualbeta dose by measuring beta activity using the liquid scintilation technique VNU Journal of Science, Mathematics - Physics Vohime 24 No 1, (2008)pp 36-4L Determination of the 15 MeV bremsstrahlung spectrum from thin W targit on the microtron MT-17 accelerator VNU Journal of Science, Mathematics Physics 24,No 2, (2008) pp 81- 87 Isomeric yield ratios for "^^Fe(Y,xnp)^^"''^Mn reaction induced 50,60 and 70 MeV bremsstrahlung photons VNU Journal of Science, Mathematics Physic 24, No 18 (2008)218-223 ^ f Tinh hinh kinh phf cua de tai: T6ng kinh phi cua da tai: 60.000.000d Chi phi dugc su dung dung qui djnh: Thanh toan dien nuac: 2.400.000d Chi phi mua vat tu hoa chSt: 9.200.000d Thue chuyen gia nuac: 28.000.000d Cong tac phi: 10.200.000d Hoi nghi: 7.500.000d Van phong pham: soo.oood Cac chi khac (quan ly phi): KHOA QUAN LY 2.400.000d CHU TRI DE TAI PGS.TS Nguyen The Binh TS Bui van Loat TRirOTVG DAI HOC KHOA HOC TU" ^fHIEN PHOHI^U TRUONO Ji qwi'^.^./Moa/n^^LdSnaf SCIENTIFIC PROJECT Branch: Physics Project category: National Level Title: Code: QG 07-06 Managing Institution: Vietnam National University, Hanoi Implementing Institution: Hanoi univercity of Science, Faculty of Physics Collaborating Institution Coordinator Key Implementers Via Thanh Mai Tran The Anh Nguyen Thi Thanh Tam Nguyen Tien Quan Phiing Thi Nguyet TS Pham Due Khue ThS Kim Tien Thanh TS Nguyen Quang Mien ThS Nguyen Xuan Ku ThS Hoang Huu Due Duration: From 1/5/2007 to 20/1/2009 Main results: Investigate the energy spectrum of bremsstrahlung photons emitted from the thin W bombarded by 15 MeV electron beam Bremsstrahlung energy spectrum from thin W target produced by 15 MeV incident electrons was determined by a combination of measurements and theoretical calculation The shape of spectrum was calculated by Monte-Carlo method using the code EGS4 The photon flux measurements were performed based on the activation technique using the high pure metallic foils The radioactivities of the irradiated foils were measured by using a gamma spectrometer with a high energy resolution HPGe detector Neutron yields from thick Ta and Pb target bombarded by 65 MeV electron beam was determined by photon activation technique and the radioactivities of the irradiated foils were measured by using a gamma spectrometer with a high energy resolution HPGe detector Angular characterization of 15 MeV and 65 MeV bremsstrahlung photons from W-target were determined The isomeric yield ratios for the "^^Fe(y,xnp)^^"^^^Mn reaction induced by 50,60 and 70 MeV bremsstrahlung photons were determined using the activation and y-ray spectroscopic methods The bremsstrahlung beams were provided from the test Pohang electron linac The isomeric yield ratios were determined from the measured activities of the produced nuclei in irradiated foil samples The y-ray activities were measured by with a calibrated highpurity germanium detector, HPGe The present results for the reaction "''^Fe(y,xnp)^^"''^Mn measured at 50,60and 70 MeV bremsstrahlung photons are 0.27+0.03, 0.33±0.04 and 0.34±0.04 The present results measured at 50 and 60 MeV bremsstrahlung are the first time reported So, our data contribute to fill in the energy between 30 and 100 MeV MUC LUC • • M6DAU 11 C H U O N G C O C H E SINH BLTC X A H A M V A N O T R O N T R E N M A Y GIA TOC ELECTRON 12 1.1 Ca che sinh buc xa ham tren may gia toe electron 12 1.1.1 Do mat nang lugng ciia electron moi truang vat chat 12 1.1.2 Cac dac trung ciia buc xa ham 19 1.2 Ca che sinh natron tren may gia toe 25 1.2.1 Phan ung quang hat nhan sinh natron 25 1.2.2 Dac trung cua quang natron 31 1.2.3 Co che sinh notron tu chum bii'c xa gamma nang lugng cao 34 CHLTONG P H U O N G PHAP VA KY THUAT THU^C NGHIEM TRONG NGHIEN CLTU DAC TRU>JG CUA BUC XA HAM VA NOTRON 35 2.1 Phuang phap xac dinh dac trung cua birc xa ham va natron sinh tir may gia toe electron 35 2.1.1 Mad^u 35 2.1 Phuang phap kich boat phong xa 36 2.1.3 Xac dinh thong lugng ciia biic xa ham 42 2.1.4 Xac dinh thong lugng ciia natron 42 2.2 Ky thuat ghi nhan va phan tich gamma 43 2.2.1 Ph6k8 gamma 43 2.2.2 Xac dinh hieu suat ghi ciia detector 44 2.2.3 Phan tich ph6 gamma 46 2.3 Mot s5 hieu chinh xac dinh cac dac trung birc xa ham va natron theo phuang phap kich boat phong xa 48 2.3.1 Hieu chinh sir suy giam cua thong lugng buc xa kich boat 48 2.3.2 Hieu chinh sir tu hap thu ciia mau 49 2.3.3 Hieu chinh thai gian chet va chong chat xung 49 2.3.4 Hieu chinh can nhilu phong xa 51 2.3.5.Ty so tiet dien dong phan 52 CHUONG NGHIEN ClTU PHAN BO CUA BlTC XA H A M VA NOTRON TREN MAY GIA TOC ELECTRON 53 3.1 Xac dinh dac trung phan bo theo goc cua buc xaham 53 •J 3.2 Xac dinh nang lugng ciia hue xaham 57 3.3 Suphu thugc ciia buc xaham vao khoang each 62 3.4 Phan bo thong lugng ciia natron 64 3.4.1 Phuang phap xac dinh phan bo natron theo be day bia 65 3.4.2 Phan bo thong lugng ciia natron nhiet bia Pb,Ta .66 3.4.3.Phan bo thong lugng ciia natron nhanh bia Pb 71 3.4.4 Phan bo theo goc natron phat tu bia W mong 74 KET LUAN 76 TAI LIEU THAM KHAO 78 MdoAu Hien ton tai nhieu nguon buc xa natron va gamma khac nhau: Nguon dong vi, may gia toe, 16 phan ung Cac nguon khac ve hinh hoc, kich thuac, suat lugng va ca che sinh cac buc xa gamma va natron Cac buc xa natron va buc xa gamma dugc phat tu cac nguon khac co dang nang lugng va phan bo goc khac De khai thac va sii dung cac buc xa tren vao muc dich nghien cuu can phai hieu ro nhung dac diem phan bo nang lugng va phan bo theo goc ciia thong lugng buc xa phat xa Vi vay viec nghien cuu ca che phat cac loai hue xa tren va nhat la xac dinh bang thuc nghiem nhirng dac trung ciia ciia chung la mot doi hoi thuc te khach quan Vai viec xuat hien may gia toe electron c6 nang lugng cang Ian cho phep tao chum buc xa gamma va natron c6 nang lugng cao va thong lugng Ian Chum buc xa ham va notron sinh tu may gia toe nang lugng cao dugc ung dung nhieu ITnh virc khoa hoc cong nghe va cac linh virc khac t r Buc xa ham dugc phat tu may gia toe electron la ket qua tuang tac ciia chum electron dugc gia toe vai bia thuong lam bang nhung kim loai nang Trong may gia toe electron, ncrtron dugc phat thuc chat la buc xa thu cSp dugc sinh chu yeu tu cac phan ung quang hat nhan(7',xn)va qua trinh phan bach dugc gay bai hue xa gamma nang lugng cao Cac dac trung nang lugng va phan bo theo g6c ciia biic xa ham va buc xa natron dugc sinh tu may gia toe phu thugc vao nang lugng ciia electron va hinh dang kich thuac cua bia Mu6n khai thac co hieu qua cac nguon buc xa noi chung va chum buc xa ham va natron sinh tu may gia toe electron noi rieng can phai nSm dugc ca chi tao va cac dac trung ciia chiing Vi vay nghien cuu co chi sinh buc xa ham va natron dugc sinh tuang tac ciia electron vai bia CO y nghTa khoa hoc va thirc te Ket qua xac dinh bang thuc nghiem cac dac trung nhu ph6 nang lugng, phan bo thong lugng cua buc xa gamma va natron 10 Tom t^t ket qua nghien cihi: - Da tim hieu ca chS sinh buc xa ham va natron electron dugc gia toe tuane tac vai vat chSt, dac diSm cua ph6 birc xa ham va natron dugc sinh I - Xac dinh bang thuc nghiem suat luong cua mot s6 phan hat quang hat nhan ; - Xac dinh bang thuc nghiem dac trung phan b6 theo goc cua chiim buc xa ham phat nang lugng cue dai 65 MeV phat tu bia W mong thong qua viec xac dinli sir ' phu thuoc cua suat lugng phan ung quang hat nhan "'/lw(x,«)''"/l2/ Ket qua thuc i nghiem chi rang cac bijc xa ham co xu tha bay theo huang uu tien ve phia truac i - Bang phuang phap mo phong ket hgp vai s6 lieu thuc nghiem da ti6n hanh xac dinh ph6 ! nang lugng ciia birc xa ham sinh chum electron nang lugng cue dai 15 MeV tir may ' I gia toe MT-17 tuang tac vai bia mong KSt qua thu dugc dang ph6 nang lugng cua buc xa ham nang lugng cue dai 15 MeV phat tu bia W mong eo dang phu hgp vai ket qua thu | dugc tu cac tac gia khac da cong bo j I - Bang phuang phap lieu true tiep va detecta nhiet huynh quang da xac dinh dugc dang ; buc xa photon nang lugng cue dai 15 MeV phat tu may xa tri tai benh vien K ket : qua chi rang khoang 20 em tinh tu tam cua true thong lugng ciia chum photon ! bang phang Kien nghi ve quy mo va doi tugng ap dung nghien cuu: Phuang phap xac dinh phan bo thong luang cua hue xa photon phut tir may gia loc dung xg tri co the dp dung doi vai cac bai toan xac dinh phan bo lieu buc xa hat nhan Chu nhiem de tai Ho va Ten Thii truang ca quan Chii tich Hoi d o n g Chu tri dc lai danh eia chinh vi Ky ten va dong dau Ouan i\ di- lai Bui Van Loat i Hgc ham, hgc Thu truong ca quan TS.GVC TI.GIAM06C ' pfr WydNG m t^HOA HQC - c6Nb NGH^ DAI HOC QUOC GIA HA NOI f)t TAI OAC BIET CAP DHQGHN Ten de tai Tieng Viet: Nghien cihi met so dac iiiitig ciia co che sinh burc xa ham va notron trfin may gia t6c electron va m6t so ling dung Tieng Anh: Study of the characteristics of bremsstrahlung photons and neutrons on the electron accelerators and applications Ma s6: QG- 07-06 Thdi gian tbijrc hien: 24 thang Bdt d£u ti^ thang 05 nam 2007 defn thang 05 nam 2009 £>€ tai tliuoc linh vuc uu tien Tang cudng dao tao va nghien cihi khoa hgc nganh Cong nghe hat nhan Be tai co trung vol mot de tai da ho^c dang tien hanh khong? Neu co neu ly Khong ChiJtri detai - Ho va r^fr BLiI VAN LO VT /Vc;/r? ' ••''''' - • Nam smh: 1958 - Chuven mon dao iao: V|L ly Hat nhiin -fguyCM] ui - Hoc ham hoc vi: Tien >I - Chicc vu: Can bo giang liay - E),m \' rong tdc: Khoa V^t iy Tnri.-mg Da; hoc Kh(^a hoc Tir nhien DHQGHN - Diit cn: ';•:-: he: 334 - Nguv;'n "'V^i - ~^;iiv^ '^ n Hii Noi Tom tit hoat dong nghien ciru cua chu tri de tai fCic cnu(^n^ n-inli de hn nghien cihi khoa hoc da (hum gia, cac cong trinh da c.-n L^ 06 tien quan tin phucfng hu&ng cua de tai} Ten di tai/c6n? trinh Tli each Tham sia Cap quan ly/ncn cong bd Tac gia Tuydn tap bao cao khoa hoc H6i nghi Khoa hoc Tiirong Dai hoc Khoa hoc lin thii 3, Ha N6i 11-2002, Tr, 98-102, BQi Van Loai: Su dung Solur - cell ghi nhan manh phan chia hat nhfln D Karamatis, M pedt, RV.loat, L ^QQj I Penot, M.ftavicff, J.6.TTK)mas c^xure radioactive de neutrons par le '^Th entre 60 Key et MeV Le H6ng Khiem, Nguyen Quang Mien, Biii Van Loat (2004) "Die tnmg tham s6 ddng hoc nhiet huynh quang cua LiF (Cu, Mg, P) NhQng v& (M hien dai ciia vat iy ch& ran, tap i n - A Tr 81 - 85 2005 Nguyen Quang Mien, Kli Van Loat (2(X)5) "Thermoluminescence properties of the different size grains" , Mcxiem problems in optics and Spetroscopy, Vol 3., tr: 190- 195 Nguyen C^ang Mien, Bui Van Loat, Lt Khanh Ph6n, Le Canh Lam (2006) •'Nghien cuu dO nhay nhiet huynh quang 2006 i ciia thach anh, cajLxi va fenspat, Tuy^n tap cac bao cao Hb va Trdn Diic Thiep (2005) Doi voi cac nsuon biic xa ham va natron sinh tircmg tac cua electron vcyi cac bia ham la'kim loai nang cung nhu cac nguon biic xa sinh tir electron nang Itrcmg cao (hang tram MeV va GeV) so lieu thuc nghiem chua nhieu sir phu^hcfp giua cac ket'^qua thirc nghiem va tien doan ly thuyet chua cao Vi vay nhung nam gan day tren the gioi va Viet Nam nhieu tac gia da tap trung nghien cuu dac trung phan bo nang lugng va goc cua notron va biic xa ham dugc sinh tren cac bia kim loai nang dac biet doi vdi chum electron nang lugng cao tir ham tram MeV tro len, 'Vrilla kitamuna (2003) Nguyen Van D6 (2006) Viec tnen khai va thuc hien thiuih cong de tai gop phan lam sang to ca che tao biic xa ham va notron tuong tac cua electron dugc gia toe voi kim loai nang dona thm h6 sung cac so lieu thuc nghiem ve dac trung cua birc xa notron vii'biic xa ham electron nang lucmg cao vm vat chat tao Cac kcL qua thu duoc cua Je lai ia ca sa khua hoc de ine'n co hicu c;ua viec x'k dinh cac dac tnms ciia birc xa ham va natron inri tren may gia toe electron se dt'oc trang^bi tai Bo mon Vat ly hat nhan Khoa Vat !y Tru-ong Dai hoc Khoa I w Tu nhTen CJc thong -^o dac irung ve phan bo goc thong s(5 dac trims cua '-u'c xa ham 'a natron ,!.nh tren may gia loc elcctr-n ua B(p , mon Vat iy hat nhan la ca sa de' trien khai cac nghien ciru ca ban va utnii dung tiep theo Ddi vdi dao tao, ke't qua ciia de iai se cho phep xay dung mgt so' bai thirc tap xac dinh cac dac trung cua phci biic xa ham va natron sinh tren mav gia tdc electron tai Bo mdn, gop phdn nang cao chat lugng dao tao ngfinh cong nghe hat nhan tai Trudng Dai hgc Khoa hgc Tu nhien A.Facure, R.CFalcao, A.X.Silva, V.R.Crispim, J.C.Vitoidli A sUidy of neutron spectra from medical linear accelerators .Applied Radiation and Isotopes 62(2005)69-72 G.N.Kim, et al Measurement of photoneutron spectrum at Pohane Neutron Facility Nucl Instr and Meth A 485 (2002) 458-467 M.Yuly et al A test of high-energy electron bremsstrahlung calculations Nucl Instr and Meth A 488 (2002) 262-270 Marshall R.Cleland, Lewis A.Parks Medium and high-energy electron beam radiation processing equipment for comercial applications Nucl Instr and Meth B 208 (2003) 74-89 Nguyen Van Do and Pham Due Khue Neutron yields from thick Ta target bombarded by 65 MeV electron beam Communications in Physics Communications in Physics Vol 14, No (2004), pp.209-214 Nguyen Van Do, T.D.Thiep, P.D.Khue, N.N.Son Bremsstrahlung ladiation production frx)m 15 MeV electron beam and its applications Proc of the International Workshop on Particle Beam and Plasma Interaction on Material, ChiangMai, Thailand, Januaiy 31- Febmaiy 1, 2002 pp.39-42 Yuri M.Tsipennyuk The Microtron development and appbcation Taylor & Francis, 2002 Van Do NGUYEN, Due Khue PHAM, Due Thiep TRAN, Van Duan PHUNG Young Seok LEE, Hee-Seock LEE, Moo-Hyun CHO In Soo KO and Won NAMKUNG , A.K.M Moinul Haque MEAZE, K DEVAN and Guinyun KIM Measurement of Neutron and Photon Distributions by Using an Activation Technique at the Pohang Neutron Facility Toumal of Korean Phvsical Society, Vol 48 No 3, March 2006 pp 382-389 • Ly chgn de tai : May gia tdc electron !a thiet bi tao eric electron nang lugng t;ao B.ang each sir dung fiang tac cua cac electron da dugc gia tdc vdi vat chiit co the Iao cac ngudn burc xa ham va notron c6 nang lugng va cudng idn Cac qua trinh vat Iv xav chiim electron dugc gia tdc ban vao bia ham Ui rat phiic tap Co che m.at nang lugng ciia electron, co che sinh biic xa ham va natron cung nhu dac trung cua cac birc xa la nhflng v^n de luon cin dugc lam sang t6, diic bie: la r vung nang lugng cao Cic dac rimo cua phd nang Immg cung nhu pnin b5 ciia biic \a hanri a notron iren c^: ",Ay gia :dc eieciron khong chi phu 'h':dc \iio nang iirrng cua cnum eiccirun -ai nvi phii thc-cc y.iv -.ii i cu, >>.:•.n livjoc •-:» :n li'c UJ bia hiinv Do i'' O'^ !chai thac cd hieu qua ca ngiuin ' K VJ n:'y cwi ;.ha vj., dinh ch:nh x.' c i : ihong ih::o nan; iuc^ig ua rx va h.-.-i sinh^a tren cac hat nhan bia nang 'r^n hem c-c-.:: ^n na may gu [cc Nghien cmi phan bo ncrtron tao bcri chiim electron nang iuong 15 MeV 12.Cau true dir kien bao cao ket qua cua de tai (chi net hod cac chumg muc) Muc luc Madiu Chirofng 1: Ca ch€ sinh biic xa ham va ncrtron tren may gia t6c i, Ccr ch^ sinh biirc xa ham tren may gia toe electron l.l.M^t mat nang cua electron txong vSt ch^t 1.1.2.Cac dac tnnig cua bu:c xa ham l.2.Ca ch^sinh notron tren may gia toe electron 1.2.1 -Co ch^ sinh sinh notron L2.2.Cac dac tnmg cua quang ncnron 1.2.3.Co che sinh notrdn tir chum electron nang luong cao Chircmg 2: Phuang phap va ky thuat thuc nghiem six dung nghien cull dac tnrng biic xa ham va ncrtron, 2,L Phircmg phap ncrtron va birc xa ham 2-Ll.Xac dinh hoat phong Ka 2.1.2.Xac dinh tiiong luotig cua narron va bic xa ham 2.I3.Xac difih r,cri:on nhar.h 2.2,Ky thuat ghi nhar; va phdn tich pr^o gwwrui 2.3.Cac hieu chiuh nhi^u phong xa ^, ^ v t_^ ^: >n uv Ml-* h'fc xa h\}^ vi nettion tren may gia toc I l l fii • • t rr:.-! ^'^3.! Pho o^n^: y.:j )i :,rH'\';,^\- \,i H; in - • : - - a ^::rc ; i-i'-: ^^.: 'i- r-r-' ,!MVV ^ l a l'"> Nghien cihi phan bo ncrtron tao bcri chum electron nang lirong 15 MeV 12.Cau true du kien bao cao ket qua cua de tai (chi net hod cac chucmg muc) Muc luc Mad^u Chuang 1: Ca c\\€ sinh biic xa ham va natron tren may gia tdc 1.1 Ca ch^ sinh buc xa ham tr6n may gia toe electron l.LM^ mat nang cua electron vat ch^t L2.Cac date trung cua biic xa ham l.2.Ca chtf sinh natron tr^n may gia toe electron 1.2.1 Ca ch^ sinh sinh notron 1.2,2.Cac dac tnmg ciia quang natron 1.2.3.Ca che sinh notrdn tir chum electron nang lugng cao Chuang 2: Phuang phap va ky thuat thuc nghiem sir dung nghien cuu dac trung buc xa ham va natron 2.1 Phuang phap ncrtron va birc xa ham 2.1.1 -Xac dinh hoat phong \a 2.1.2.Xac dinh tliong liforig cua nafron vii b^Jc xa ham 2.1.3.Xac dinh pht5 ccnron nhar.b 2.2.Kv thuat uhi nhan va phan tich pno g;imn^a 2.3.Cac hicu chinh nhi^u phong xa Chucms 3: Nghien cuu phan be CULI b^fc xa nan va nLnion iren may gm toe , 3.; P'-^'i 3.1.: _ • ' ^ ^ b^- • pr TI {}) :\ ! ! '"Ii u ; 's , i '.'- > M- Ph'M- »a^l!2 M.' \ J •• re y:^ ' ' [ : ' ^ • ' • • • ' :\'' ^ ' \']\ I : • :^A.3 Phan bo' cua buc xa ham theo khoang each 3.2 Nghien cihi dac trung ph^ ^ ^'