- CdZnTe. À.À. Çàõàð åíêî, À.À. Âåðåâêèí... Ìîäåëèðîâàíèå ôóíêöèè îòêëèêà... [1, 2]. [1 4]. (, 241 Am, 137 Cs, 60 Co)., [5]. CdZnTe (, 661,67, CdZnTe

Transcription

1 «Â³ñíèê Õàðê³âñüêîãî óí³âåðñèòåòó», ¹ 832, 2008 ñåð³ÿ ô³çè íà «ßäðà, àñòèíêè, ïîëÿ», âèï. 4 /40/ 71 Ìîäåëèðîâàíèå ôóíêöèè îòêëèêà CdZnTe -..,..,..,..,.. «-» 61108,.,. 1 rybka@kipt.kharkov.ua CdZnTe -. CdZnTe Am 137 Cs. : 241 Am, 152 Eu 137 Cs. CdZnTe. :, CdZnTe,, -,, -, EGSnrc. ( ) E - E. - [1, 2]. -, - [1 4].,, (, 241 Am, 137 Cs, 60 Co).,.,, [5]. CdZnTe, -, - ( 59,54, 241 Am 122, 57 Co) [6]. (, 661,67, 137 Cs) ( Si Ge ) -, [7]. CdZnTe 5 % [8].,,, -, [9]. CdZnTe, -,. - (< 90 %), 10 %. [10], [6]. CdZnTe - ~ CdZnTe. CdZnTe 241 Am 137 Cs Am, 137 Cs 60 Co.

2 72 «Â³ñíèê Õàðê³âñüêîãî óí³âåðñèòåòó», ¹ 832, 2008 CdZnTe [11]. - ( 241 Am, 137 Cs).. 1. (ENC), (e ) [12]. 3,, ENC 140 e [15]. 1.. Cd 0,9 Zn 0,1 Te ( ) ( ), 2 /, ( ) e 1, ( ) h 1,3 10 5, 6 6 3, 300, < 3, / 0,75, 1, / 1,0 (ENC), e 290, [12], - ( ), 100% E Si., Y, E 0 [13]., Si CdZnTe - w (3,2 Si 4,64 CdZnTe). q adc 16,6±0,1 e /, 4..2 CdZnTe, Am ,.3 - Si Cs., PeakFit [14],. 2. (CCE). 2 - E N phqadc CCE, (1) E w N ph,. CCE, ( ) e,h (. 1). 661,67 ( / ~ 4:1) [15]., ,, (FWHM). [7],,,.

3 ñåð³ÿ ô³çè íà «ßäðà, àñòèíêè, ïîëÿ», âèï. 4 /40/ Ìîäåëèðîâàíèå ôóíêöèè îòêëèêà Cs CdZnTe Am CdZnTe 230 (1) 300 (2) (1) 300 (2). - (184,3 ). / 2:1, FWHM. 2. CdZnTe. 241 Am -, 59,54 661,67 (U ), FWHM, e ± , % 20,7 0,2 17,0 0,3 10,3 0,2 9,1 0,2 CCE, % 28,4 0,2 36,1 0,2 28,9 0,2 36,1 0,2 / 8:1 8,6:1 4,4:1 3,7:1 CdZnTe, [3, 15]. - EGSnrc [16]. EGSnrc -,., EGSnrc, -. - E E i,. CCE,. CdZnTe w. [17]. [18, 19] E i /w 2 2 Ei 2 Ei F enc a1, (2) w w F ( 0,1 CdZnTe) [20], enc ENC, [12], a 1, -. (2), t 10 2 [7]. a 1 E i, ~ 100 a 1 [18]. 137 Cs

4 74 «Â³ñíèê Õàðê³âñüêîãî óí³âåðñèòåòó», ¹ 832, 2008 CdZnTe - ( ) e,h a 1 (2). FWHM/2,35. (2) E i E, -. 59,54 ( 241 Am) 661,67 ( 137 Cs). (. 2) 241 Am (13,9 17,2 ) 137 Cs ( 32,2 ), (2) Cs, 184,3 (.3)..4 2 E U = 300,., E.4 w. a 1 = (1,9 0,12) CdZnTe..5. CdZnTe - 59,54 ( 241 Am). U =300. a 1 ( 2, ) [4]. [7], CdZnTe, Ge..5 CdZnTe,. 1, - 59,54 ( 241 Am)., (,, FWHM).. 6 CdZnTe 137 Cs (. 6 ) (. 6 ). PeakFit, ,67 á.,,.,,, ( ) h, (. 1) [5, 7]. (. 6 ) ~ (184,3 ).,, a 1 (E ) (2). - (184,3 ) 137 Cs (.3) CdZnTe, FWHM. a Eu, (13,5 ) -,

5 ñåð³ÿ ô³çè íà «ßäðà, àñòèíêè, ïîëÿ», âèï. 4 /40/ Ìîäåëèðîâàíèå ôóíêöèè îòêëèêà CdZnTe U = Eu., a 1 121,8, 244,7 344,3. ) ). 6. CdZnTe 137 Cs (U =300 ) ) 661,67, ). CdZnTe - [21] (. 8) Am, 137 Cs 60 Co.. 7. CdZnTe Eu.. 8. CdZnTe U =300., 661, Cs CdZnTe : 214 Am 137 Cs., 661,67,,, 57 Co (122 ) 152 Eu. a 1, -, 152 Eu., a 1 121,8; 244,7 344,3 152 Eu., CdZnTe 241 Am, 137 Cs 152 Eu. CdZnTe Am, 137 Cs 60 Co,. CdZnTe - -.

6 76 «Â³ñíèê Õàðê³âñüêîãî óí³âåðñèòåòó», ¹ 832, Sood A., Gardner R. A new Monte Carlo assisted approach to detector response functions // Nucl. Instr. & Meth. B Vol P ,..,... - // , ,..,... CdTe (CdZnTe) - // Stelji M., Miloševi M., Beli ev P. Monte Carlo simulations of the pulse-height response function of germanium detector // Proceedings 52nd ETRAN Conference, Pali, June 8-12, NT Sato G., Parsons A., Hullinger D. et al. Development of a spectral model based on charge transport for the Swift/BAT 32K CdZnTe detector array // Nucl. Instr. & Meth. A Vol P Liu J.C., Nelson W.R., Seefred R. Response Calculations of the CdZnTe Detector Using EGS4 // Proceedings of the Second International Workshop on EGS, 8 12 August 2000, Tsukuba, Japan KEK Proceedings P Bolotnikov A.E., Camarda G.C., Wright G.W., James R.B. Factors Limiting the Performance of CdZnTe Detectors // IEEE Trans. on Nucl. Sci Vol. 52, 3. P Budtz-Jorgensen C., Kuvvetli I., Westergaard N.J. et al. The X-ray imager on AXO // Nuclear Instr. & Meth. A Vol P Kalemci E., Matteson J.L. Investigation of charge sharing among electrode strips for a CdZnTe detector // Nuclear Instr. & Meth. A Vol P Gunnink R., Arlt R. Methods for evaluating and analyzing CdTe and CdZnTe spectra // Nuclear Instr. & Meth. A Vol P Rybka A.V., Davydov L.N., Shlyakhov I.N. et al. Gamma-radiation dosimetry with semiconductor CdTe and CdZnTe detectors // Nucl. Instr. & Meth. A Vol P ,..,... //. :,, (15) Matz R., Weidner M. Charge collection efficiency and space charge formation in CdTe gamma and X-ray detectors // Nucl. Instr. & Meth. A Vol P URL ,..,... CdZnTe - // Kawrakow I. Accurate condensed history Monte Carlo simulation of electron transport. I. EGSnrc, the new EGS4 version // Med. Phys Vol. 27, 4. P Akutagawa W., Zanio K. Gamma response of semi-insulating material in the presence of trapping and detrapping // J. Appl. Phys Vol. 40, 9. P Kozorezov A.G., Wigmore J.K., Owens A. et al. Resolution degradation of semiconductor detectors due to carrier trapping // Nucl. Instr. & Meth. A Vol P Owens A. Semiconductor materials and radiation detection // J. Synchrotron Rad Vol. 13. P Devanathan R., Corrales L.R., Gao F., Weber W.J. Signal variance in gamma-ray detectors A review // Nucl. Instr. & Meth. A Vol P ,..,... CdTe, CdZnTe ( 4.15) //, /..,...., SIMULATION OF RESPONSE FUNCTION OF CdZnTe DETECTORS FOR GAMMA-RADIATION DOSIMETRY A.A. Zakharchenko, A.A. Veryovkin, V.E. Kutny, A.V. Rybka, M.A. Khazhmuradov National Science Center Kharkov Institute of Physics and Technology 1, Academicheskaya St., Kharkov, Ukraine, rybka@kipt.kharkov.ua A procedure allowing to obtain a response function of CdZnTe planar detector used for gamma-ray dosimetry is developed based on the Monte-Carlo method. For reliable reconstruction of the detector response function the experimental spectra only from three sources: 241 Am, 152 Eu and 137 Cs will suffice. The proposed method was used for the calculation of the discrete sensitivity of CdZnTe dosimeter detector module. KEY WORDS: response function, CdZnTe, detector, gamma-radiation, dosimetry, Monte-Carlo method, EGSnrc.