2001 4 17 1 ICRP90 (AP ) ICRP 2 2.1 (photoelectric eect) (coherent scattering) (incoherent scattering) ( (pair creation) (triplet creation)) = photo + coh + incoh + pair (cm ;1 ) (1) (linear attenuation coecient) (mass attenuation coecient, m (cm 2 =g), ATMU) m N 0 (t cm) ( ) N 0 exp(;t) (Buildup Factor) (ATMUKN) ANS-6.4.3[1] 1
[2] ATMUKN [3] (ATMU ATMUKN)[4] 1 2.2 ( ) X tr = f photo photo + f incoh incoh + f pair pair = E h 0 (2) h 0 E 1 f photo =1; X h 0 f incoh f pair =1; <h>+x h 0 =1; 2mec2 h 0 =1; 2mec2 +X h 0 for pair creation for triplet creation X: 1 X <h>: m e c 2 : X KX- X X 1993 Seltzer [5] 1961 Berger [6] Al Fe X Hubbell 1969 [7] 18 K Higgins 29 14 NIST [8] Hubbell [5] [13] [9] 2 9 >= > (3)
K = E tr m : (4) E tr m (Gy=J/kg) (2) ( tr = cm 2 /g) (h 0 MeV/cm 2 ) K = tr = h 0 (MeV=g) = 1:602 10 ;10 tr = h 0 (Gy) (5) ICRP 74[10] (Table A.1) ICRU- 47[11] 1982 Hubbell [12] ( ) Seltzer g ( X Private communication Table A.1 1-g ) (Table A.21) 1995 Hubbell [13] g K a = 1995 Hubbell ( ) ICRP 1 1982 Hubbell ICRU 47Table A.1 1 ; g Higgins [8] 2.3 X X (collision loss) X (radiation loss) (E c ) " c = 800 (MeV) (6) Z +1:2 [14] X ( X g) en en = tr (1 ; g) (7) g X Hubbell [6, 15, 7, 16, 12, 8, 13] [13] NIST (http://physics.nist.gov/ Physics and Reference Data) 3
1 1982 Hubbell Higgins g 1 1 MeV 0 1 1 Habbell 1.04 Ratio to µ (Hubbell - 1995) en 1.03 1.02 1.01 1 0.99 0.98 µ tr (Hubbell-1982) µ en (Hubbell -1982) µ tr (Higgins - 1992) 0.97 0.01 0.1 1 10 Photon Energy (MeV) 1: (Hubbell en (1995 ) ) (collision kerma) K C = en = h 0 (MeV=g) = 1:602 10 ;10 en = h 0 (Gy) (8) D = E m (9) E m 4
\ " D = K C = 1:602 10 ;10 en = h 0 (Gy) (10) Carlsson [17] 1 MeV g =0 10MeV 4% 2.4 1cm X = Q (11) m Q m X = e W (1 ; g)k = e W K C: (12) W 1 33.97 J/C(=33.97 ev/e) [11] C=kg (R) 0 C 1 1cm 3 (0.001293g) 1esu 1R = 2:58 10 ;4 C/kg W ICRU 47 Table A.1 \The exposure, X, is not accurately determined at energies above 3 MeV since there is signicant departure from electronic equilibrium." 3 MeV 5
1 1 ; g[11] [12, 13] Energy m m tr = 1 1 ; g[11] en =[12] tr =[8] en =[13] ATMU ATMUKN (MeV) (cm 2 /g) (cm 2 /g) (cm 2 /g) (cm 2 /g) (cm 2 /g) (cm 2 /g) 0.01 5.120 4.9580 4.640 1.00 4.640 4.742 4.742 0.015 1.614 1.5240 1.300 1.00 1.300 1.334 1.334 0.02 0.7779 0.7206 0.5255 1.00 0.5255 0.5391 0.5389 0.03 0.3538 0.3247 0.1501 1.00 0.1501 0.1538 0.1537 0.04 0.2485 0.2311 0.06694 1.00 0.06694 0.0684 0.06833 0.05 0.2080 0.1964 0.04031 1.00 0.04031 0.0410 0.04098 0.06 0.1875 0.1791 0.03004 1.00 0.03004 0.0304 0.03041 0.08 0.1662 0.1614 0.02393 1.00 0.02393 0.0241 0.02407 0.10 0.1541 0.1509 0.02318 1.00 0.02318 0.0233 0.02325 0.15 0.1356 0.1341 0.02494 1.00 0.02494 0.0250 0.02496 0.20 0.1233 0.1225 0.02672 1.00 0.02672 0.0267 0.02672 0.30 0.1067 0.1063 0.02872 1.00 0.02872 0.0287 0.02872 0.40 0.09549 0.09524 0.02949 1.00 0.02949 0.0295 0.02949 0.50 0.08712 0.08694 0.02966 1.00 0.02966 0.0297 0.02966 0.60 0.08055 0.08041 0.02953 1.00 0.02953 0.0296 0.02953 0.80 0.07074 0.07065 0.02882 1.00 0.02882 0.0289 0.02882 1.0 0.06358 0.06349 0.02787 1.00 0.02787 0.0279 0.02789 1.5 0.05175 0.05168 0.02552 0.996 0.02545 0.0256 0.02547 2.0 0.04447 0.04449 0.02354 0.995 0.02342 0.0236 0.02345 3.0 0.03581 0.03573 0.02073 0.991 0.02054 0.0207 0.02057 4.0 0.03079 0.03072 0.01886 0.988 0.01866 0.0189 0.01870 5.0 0.02751 0.02745 0.01765 0.984 0.01737 0.0177 0.01740 6.0 0.02522 0.02517 0.01678 0.980 0.01644 0.0168 0.01647 8.0 0.02225 0.02220 0.01565 0.972 0.01521 0.0157 0.01525 10.0 0.02045 0.02040 0.01500 0.964 0.01446 0.0150 0.01450 1 Hubbell 1982 ICRU 47Table A.1 1 ; g 6
3 2 10 2 [18] X 2 [18] Primary Secondary Secondary Charged Energy Energy Particle Energy (E E ) c (E L ) c (E E ) u (E L ) u (E R ) u e ; e + 1.5 - - - 0 0.5.5 0 2.5 -.5 -.3 0 0 0 0 3.5 -.5-0 0.5 0 0 4.5 -.5-0.2.5 0 0 5 1.0.5.5 -.3 0.5.5 0 6 1.0.5.5-0 0 1.0.5 0 7 1.0.5.5-0.2 1.0.5 0 8 3.0-0.989 0.989.8 0 0 0 0 9 3.0-0.989 0.989 0 0 3.0 1.022 0 P 10 3.0-0.989 0.989 0 1.0 3.0 0 1.022 1.4 1.4 10.0 3.022 1.022 (E E ) c : (E L ) c : (E E ) u : (E L ) u : (E R ) u : (E E ) c ; (E L ) c =1:4 ; 1:4 =0 K =0:5+0:5+0:5+0:5+1:978 + 1:978 = 5:956 (MeV) (13) E E = (E E ) c ; (E L ) c +(E E ) u ; (E L ) u ; (E R ) u = 1:4 ; 1:4+10:0 ; 3:022 ; 1:022 = 5:956 (MeV) (14) X 3 X (E E ) c =(E L ) c =0 E tr > E X K C = D 7
Photoelectric effect 1 2 3 4 5 Compton Scattering 6 7 Pair creation 8 9 10 2: ( )[18] 3: D 6= K [18] 6 MeV Al Al 4 EGS4[19] [7] [13] 1mm 1mm 5 1mm Al Al 1cm 5 8
0.115 0.11 0.105 Kerma Collision Kerma Absorbed Dose cm 2 MeV g -1 0.1 0.095 0.09 0.085 0.08 0 1 2 3 4 5 Depth in Al (cm) 4: 6 MeV Al 0.1 0.004 (E E ) C -(E L ) C (MeV cm 2 /g) 0-0.1-0.2-0.3 6 MeV photon (E E ) C -(E L ) C (MeV cm 2 /g) 0.0035 0.003 0.0025 0.002 0.0015 0.001 0.0005 6 MeV photon -0.4 0 0.2 0.4 0.6 0.8 1 Depth in Al (cm) 0 1 1.5 2 2.5 3 3.5 4 4.5 5 Depth in Al (cm) 5: 1mm ((E E ) C ) ((E L ) C ) 4 9
W W 100keV 3 [20] 5 MeV 2.5cm MeV 3 [20] (MeV) a (g cm ;2 ) 0.02 0.0008 0.05 0.0042 0.1 0.014 0.2 0.044 0.5 0.17 1.0 0.43 2.0 0.96 5.0 2.5 10.0 4.9 a 5 (AP) 2 (AP) ICRP90 ( ) (AP) 4 4 1982 Hubbell[12] Seltzer g ICRP 74[10] Table A.1 ( cm ;2 ) (AP) 4 4 en =[13] (K C, ) (X, R) (AP) 6 ICRP (5), (8) (11) 10
ICRP 74 4 ICRP 47 11
4 (AP) Energy K 1 2 KC 3 X 3 MeV SvGy ;1 psvcm 2 SvGy ;1 msvr ;1 0.01 0.00653 0.0485 0.00639 0.0560 0.015 0.0402 0.125 0.0392 0.343 0.02 0.122 0.205 0.119 1.042 0.03 0.416 0.300 0.406 3.557 0.04 0.788 0.338 0.772 6.763 0.05 1.106 0.357 1.088 9.531 0.06 1.308 0.378 1.295 11.34 0.08 1.433 0.440 1.423 12.47 0.10 1.394 0.517 1.391 12.19 0.15 1.256 0.752 1.253 10.98 0.20 1.173 1.004 1.172 10.27 0.30 1.093 1.508 1.092 9.566 0.40 1.056 1.996 1.056 9.251 0.50 1.036 2.466 1.037 9.084 0.60 1.024 2.908 1.023 8.962 0.80 1.010 3.727 1.009 8.839 1.0 1.003 4.483 1.003 8.786 2.0 0.992 7.490 0.998 8.743 4.0 0.993 12.02 1.004 8.795 6.0 0.993 15.99 1.013 8.874 8.0 0.991 19.92 1.020 8.935 10.0 0.990 23.76 1.024 8.970 1 1 tr = 4 2 ICRU Report 47[11] Table A.1 2 1 en =[13] 12
[1] Prepared byd.k.trubey, \New Gamma-Ray Buildup Factor Data for Point Kernel Calculations: ANS-6.4.3 Standard Reference Data", NEUREG/CR-5740, ORNL/RSIC-49/RI(1991). [2] H. Hirayama and D. K. Trubey, \Eects of Incoherent and Coherent Scattering on the Exposure Buildup Factors of Low-Energy Gamma Rays", Nucl. Sci. Eng. 99(1988) 145-156. [3] Y. Namito, S. Ban and H. Hirayama, \Eects of Linear Polarization and Doppler Broadening on the Exposure Buildup Factors of Low-Energy Gamma Rays", Nucl. Sci. Eng. 120(1995)199-210. [4] \Photon Interaction Cross Section Library", Radiation Shielding Information Center Data Package DLC-136/PHOTX, National Institute of Standards and Technology. [5] S. M. Seltzer, \Calculation of Photon Mass Energy-Transfer and Mass Energy-Absorption Coef- cients", Rad. Res. 136 (1993)147-170. [6] R. T. Berger, \The X- or Gamma-Ray Energy Absorption or Energy Transfer Coecient: Tabulation and Discussion", Rad. Res. 15(1961)1-29. [7] J. H. Hubbell, \Photon Cross Sections, Attenuation Coecients, and Energy Absorption Coecients from 10 kev to 100 GeV, NSRDS-NBS 29 (1969). [8] P. D. Higgins, F. H. Attix, J. H. Hubbell, S. M. Seltzer, M. J. Berger and C. H. Sibata, \Mass Energy-Transfer and Mass Energy-Absorption Coecients, Including In-Flight Positron Annihilation for Photon Energies 1 kev to 100 MeV, NISTIR 4812(1992). [9] Private communication. [10] ICRP Publication 74,\Conversion Coecients for use in Radiological Protection against External Radiation", Annals of ICRP 26, No.3/4(1996). [11] ICRU Report 47, \Measurement of Dose Equivalents from External Photon and Electron Radiations", 15 April 1992. [12] J. H. Hubbell,\Photon mass attenuation and energy absorption coecients from 1 kev to 20 MeV", Int. J. Appl. Radiat. Isot. 33(1982)1269-1290. [13] J. H. Hubbell and S. M. Seltzer, \Tables of X-Ray Mass Attenuation Coecients and Mass Energy-Absorption Coecients 1 kev to 20 MeV for Elements Z=1 to 92 and 48 Additional Substances of Dosimetric Interest", NSTIR 5632, (1995). [14] M. J. Berger and S. M. Seltzer, \Tables of Energy Losses and Ranges of Electrons and Positrons", NASA-SP-3012, National Aeronautics and Space Administration (1964). [15] J. H. Hubbell and M. J. Berger,\Sec. 4.1: Attenuation Coecients, Energy Absorption Coef- cients, and Related Quantities", in Engineering Compendium on Radiation Shielding, Vol. 1, R. G. Jaeger, ed. (Springer, Berlin), 167-184(1968). [16] J. H. Hubbell, \Photon Mass Attenuation and Mass Energy-Absorption Coecients for H, C, N, O, Ar, and Seven Mixtures from 0.1 kev to 20 MeV", Rad. Res. 70(1977)58-81. 13
[17] G. A. Charlsson, \Theoretical Basis for Dosimetry", in The Dosimetry of Ionizing Radiation, Vol. 1, pp.1-75, Academic Press, INC. (1985). [18] K. R. Kase, W. R. Nelson, \Concepts of Radiation Dosimetry", SLAC-153, Stanford Linear Accelerator Center (1972) ibid. Pergamon Press, New York(1978). [19] W. R. Nelson, H. Hirayama and D. W. O.Rogers, \The EGS4 Code System", SLAC-265, Stanford Linear Accelerator Center (1985). [20] G. F. Knoll, \Radiation Detection and Measurements", (John Wiley & Son), 1979. 14