THE EGS5 CODE SYSTEM

More documents

Recommendations

Info

Figure 4.2: UCBEND simulation at 8.5 MeV (B=2.6 kG).poverb=p/(bfield*0.3)u0=u(np)v0=v(np)w0=w(np)rcurv=-iq(np)*poverbif (ustep.gt.0.1) thenustep=dmin1(ustep,0.1*abs(poverb))end ifustep0=ustepirnew=irlalpha=ustep/rcurvrenorf=1./sqrt(1.+alpha*alpha)w(np)=(w0-u0*alpha)*renorfu(np)=(u0+w0*alpha)*renorfv(np)=v0call plan2p(6,11,1,3,3,-1)call plan2p(7,5,1,11,12,-1)elsecall plan2p(6,11,1,3,3,-1)call plan2p(7,5,1,11,12,-1)end ifThe result of running UCBEND at 8.5 and 3.5 MeV is shown in Figure 4.2 and Figure 4.3,respectively, for 100 incident electrons (the red lines are electrons and the yellow lines are photons). 11 These figures were created by using a freely distributed program called “cgview,” which is briefly described insection 4.3.196
Figure 4.3: UCBEND simulation at 3.5 MeV (B=1.0 kG).It becomes clear from pictures such as these that it is easier to focus the 8.5 MeV electrons throughthe slit than the 3.5 MeV ones. A number of <strong>EGS5</strong> “experiments” can be performed rather easilynow that the basic geometry and magnetic field transport is established. For example, one canreplace the air regions and/or the copper window with vacuum in order to determine what effectthey have. What was discovered by doing this is that the copper window has the greatest effecton the transmission through the slit. Note that Figure 4.4, illustrates what happens when themagnetic field is turned off. Users interested in charged particle transport in an electric field shouldsee Rawlinson, Bielajew, Munro and Galbraith [133].4.3 Using Combinatorial Geometry with <strong>EGS5</strong>All of the user codes presented thus far have treated problems with simple geometries involvingfew regions and only basic shapes (parallel slabs and right circular cylinders). Construction of subroutineHOWFAR for such geometries is rather straight-forward, as distances to boundaries are easilydetermined for planar and cylindrical surfaces, and identifying new region numbers subsequent toboundary crossings is almost trivial when there are few regions with limited intersections. However,for simulations involving complex devices such as radiotherapy accelerator heads or high energyphysics detectors, subroutine HOWFAR can be quite cumbersome to construct. In such applications,regions can have complex shapes for which distance to boundary computations are more involved(e.g., in concave regions there can be multiple intersection points on the same surface), and/or havesurfaces which are bordered on one side by a large number of distinct volumes (e.g., at a collimatorsinterface), making region identification more difficult.As the need to simulate complex geometry is a common problem in Monte Carlo modeling,197
Page 1 and 2:
THE EGS5 CODE SYSTEM 1Hideo Hirayam
Page 6 and 7:
4.1 UCCYL - Cylinder-Slab Geometry
Page 8 and 9:
E CONTENTS OF THE EGS5 DISTRIBUTION
Page 10 and 11:
2.17 Convergence of energy depositi
Page 12 and 13:
List of Tables2.1 Symbols used in E
Page 14 and 15:
C.2 Goudsmit-Saunderson-related sub
Page 16:
With the release of the EGS4 versio
Page 19 and 20:
“shower book”.For various reaso
Page 21 and 22:
1.2.2 EGS1About this time Nelson be
Page 23 and 24:
MSCAT.These versions of EGS, PEGS,
Page 25 and 26:
ten for energies less than 100 MeV
Page 27 and 28:
- Molière multiple scattering (i.e
Page 29 and 30:
EGS5. The primary advantages of thi
Page 31 and 32:
ICRU37-compliant using the NIST dat
Page 33 and 34:
high Z materials. Del Guerra et al.
Page 35 and 36:
One of these six cross sections is
Page 37 and 38:
at low energies. The latter, couple
Page 39 and 40:
If E 1 and E 2 are expressions invo
Page 41 and 42:
The result of this algorithm is tha
Page 43 and 44:
2.4 Particle Transport SimulationTh
Page 45 and 46:
from appropriate distribution funct
Page 47 and 48:
parameters which may be needed. The
Page 49 and 50:
arrived at their values in a very m
Page 51 and 52:
Math FORTRAN ProgramTable 2.1 (cont
Page 53 and 54:
Figure 2.2: Feynman diagrams for br
Page 55 and 56:
defined byδ ij = 1 if i = j,0 othe
Page 57 and 58:
Davies, Bethe and Maximon[49] (e.g.
Page 59 and 60:
cross section given in Equation 2.4
Page 61 and 62:
and use this as the variable to be
Page 63 and 64:
we haveNow defineδ ′ = ∆ C ∆
Page 65 and 66:
This agrees with formula (10) of Bu
Page 67 and 68:
That is, using Equations 2.122 and
Page 69 and 70:
d˘Σ P air, Run−timedE=[23 − 1
Page 71 and 72:
Angular distribution formulasThe fo
Page 73 and 74:
at either x = 0, x = (πE 0 ) 2 (i.
Page 75 and 76:
The following table, derived from t
Page 77 and 78:
Figure 2.3: Feynman diagrams for tw
Page 79 and 80:
whereX 0 = radiation length (cm),n
Page 81 and 82:
whereα ′ 1 =α ′ 2 =k 0′k 0
Page 83 and 84:
+ 1 E 2′ − 1 E 1′− C 2 ln E
Page 85 and 86:
PEGS functions BHABDM, BHABRM, and
Page 87 and 88:
To find the limits of E, we first c
Page 89 and 90:
Figure 2.5: Feynman diagram for sin
Page 91 and 92:
Ī adj = average adjusted mean ioni
Page 93 and 94:
Table 2.2 (cont.)Z Symbol Atomic De
Page 95 and 96:
Table 2.3 (cont.)LABEL a m s x 0 x
Page 97 and 98:
(c) If 10.5 ≤ −C < 11.0 then x
Page 99 and 100:
obtain the real scattering angle. E
Page 101 and 102:
ρ = material mass density (g/cm 3
Page 103 and 104:
Hence,so thatln [1.13 + 3.76(αZ i
Page 105 and 106:
g 3 (θ) =θ4 ()λf (0) (θ) + f (1
Page 107 and 108:
Actually, b = 0 does not correspond
Page 109 and 110:
Assume that an electron starts off
Page 111 and 112:
At small path lengths t, a very lar
Page 113 and 114:
xFinalDirectionφΘ∆xtInitialDire
Page 115 and 116:
shown that this version of the rand
Page 117 and 118:
and as we noted earlier, they are d
Page 119 and 120:
FinalDirectionxEnergy HingesφΘt(
Page 121 and 122:
Transport Steps,∆ E = E x ESTEPEt
Page 123 and 124:
tranport step 1DEINITIAL1 DERESID1t
Page 125 and 126:
= ∆E( ∣ ∣∣∣ dE−1 ∣ )
Page 127 and 128:
Since the CSDA range is uniquely de
Page 129 and 130:
short steps accurate, but slowstep
Page 131 and 132:
Table 2.4: Materials used in refere
Page 133 and 134:
Average Lateral Displacement (cm)0.
Page 135 and 136:
100 MeV Electrons0.010.001LiCLWAlST
Page 137 and 138:
actions involving photons with ener
Page 139 and 140:
Cu 40 keVCounts (/keV/sr/source)10
Page 141 and 142:
Table 2.6: Data sources for general
Page 143 and 144:
2.16.2 Photoelectron Angular Distri
Page 145 and 146:
where r 0 is the classical electron
Page 147 and 148:
second term on the right-hand side
Page 149 and 150:
ZθkYOφe0Xk0Figure 2.23: Photon sc
Page 151 and 152:
Note the similarities and differenc
Page 153 and 154:
XZωk0Oe0YFigure 2.25: Direction of
Page 155 and 156:
W = Atomic, molecular and mixture w
Page 157 and 158:
In order to use EGS5 to answer the
Page 159 and 160:
write(6,100)100 FORMAT(’ PEGS5-ca
Page 161 and 162: ! plate is 1 mm thick!-------------
Page 163 and 164: implicit noneinclude ’include/egs
Page 165 and 166: 0.989 MeV kinetic energyBrem photon
Page 167 and 168: ! locally (in fact EDEP = particles
Page 169 and 170: inmax=max(binmax,ebin(j))end dowrit
Page 171 and 172: 0.40 0.0058 *0.60 0.0054 *0.80 0.00
Page 173 and 174: !----------------------------------
Page 175 and 176: endifif(loop.lt.3) thenwrite(6,120)
Page 177 and 178: 180 FORMAT(/’ Knock-on electrons
Page 179 and 180: common/score/escore(3), iscore(3)re
Page 181 and 182: Brem photons can be created and any
Page 183 and 184: in any combination of 31 well speci
Page 185 and 186: end doend do! nmed and dunit defaul
Page 187 and 188: ! ------------------------------clo
Page 189 and 190: if (iarg.eq.17) then! A Compton sca
Page 191 and 192: ! the general purpose geometry subr
Page 193 and 194: eturnend!--------------------------
Page 195 and 196: open(UNIT= 6,FILE=’egs5job.out’
Page 197 and 198: write(6,130)130 format(/’ Start t
Page 199 and 200: icol=* int(dlog10(ebin(j)*10000.0/f
Page 201 and 202: 0.0300 0.0000*0.0320 0.0001*0.0340
Page 203 and 204: 0.0780 0.0014 *0.0800 0.0012 *0.082
Page 205 and 206: The main purpose of this section, h
Page 207 and 208: 4.1.3 Leading Particle BiasingThe s
Page 209 and 210: • Sum the weighted energy deposit
Page 211: 4z6Vac115Pb65Air749 1012AirAir8Vac
Page 215 and 216: necessary geometry input. The follo
Page 217 and 218: Appendix AEGS5 FLOW DIAGRAMSHideo H
Page 219 and 220: subroutineannihVersion051219-1435ia
Page 221 and 222: ¡eq1anormr = 1./sqrt(anorm2)sineta
Page 223 and 224: 1br = max(br,0.D0)ekse2 = br*ekines
Page 225 and 226: 12 3br = br*pesg = eie*bryesesg.lt.
Page 227 and 228: ¤ne¤nesubroutinecollis(lelec,irl,
Page 229 and 230: ¦ne¦necallausgab(iarg)6iq(np).eq.
Page 231 and 232: subroutinecomptVersion051219-1435ic
Page 233 and 234: 3456icprof(medium).eq.3noyescallran
Page 235 and 236: subroutinecounters_outVersion051227
Page 237 and 238: 1234567noii.ne.jjyesnoledgb(ii,medi
Page 239 and 240: ©ne1 2 3neispl = (2*neispl + 1)/3f
Page 241 and 242: subroutineelectr(ircode)ielectr = i
Page 243 and 244: 7 8 9 10 11 12 13detot = e(np)-ecut
Page 245 and 246: 2324 25 26 27 282930ustep.gt.dnear(
Page 247 and 248: 4142 43 44 45 4647 48 49ecut(irnew)
Page 249 and 250: 5859 60 61 6263 64tmscat.eq.0.0noye
Page 251 and 252: 73 7475 76noedep.lt.e(np)yescallran
Page 253 and 254: subroutinehardx(charge,kEnergy,keIn
Page 255 and 256: 1 2 3 4 5iz = izziz.eq.0noxsi = zer
Page 257 and 258: 13 14 15 16 17sint.ne.0.yesrdev = m
Page 259 and 260: 19im=1im=im+1im >nmednoyesnoiprofm(
Page 261 and 262: 2223write(kmpo,1610)read(kmpi,1260)
Page 263 and 264:
26 27 28iprofm(im).ne.1noyeswrite(6
Page 265 and 266:
30 31 32 33 34esig0(i,im) = esig0(i
Page 267 and 268:
36 37 38noiedgfl(ii).ne.0.or.iauger
Page 269 and 270:
nokaug.eq.6calllshell(3)kaug.eq.7ka
Page 271 and 272:
subroutinekxrayVersion051219-1435ik
Page 273 and 274:
123dfl3aug(5,iz).eq.0.nonauger = na
Page 275 and 276:
12 3 4rnnow.le.omegal2(iz) + f23(iz
Page 277 and 278:
1 2dflx3(6,iz).eq.0.nonxray=nxray+1
Page 279 and 280:
1impacr(ir(np)).eq.1.and.iedgfl(ir(
Page 281 and 282:
12fject = (ktot - k1grd(iprt,ik1))
Page 283 and 284:
56789thr = 1./eta"Central correctio
Page 285 and 286:
1 2 3delta = delcm(medium)*del"Reje
Page 287 and 288:
89101112galpha.ge.0.0yesnoximid = 0
Page 289 and 290:
subroutinephotoVersion051219-1435"C
Page 291 and 292:
4 5 6 7 8rnnow.le.pbran(i)noyesiz =
Page 293 and 294:
121314beta = sqrt((eelec - RM)*(eel
Page 295 and 296:
subroutinephotonVersion051219-1435i
Page 297 and 298:
678910idisc.gt.0yesnoedep = 0.iarg
Page 299 and 300:
1718192021iausfl(iarg+1)ne0nocallpa
Page 301 and 302:
2728iausfl(iarg+1)ne0noircode = 2np
Page 303 and 304:
subroutinerk1Version060313-0945open
Page 305 and 306:
4 5 6j=1j=j+1j>neke-1noyesj.eq.1noj
Page 307 and 308:
18 19 20 21 22 23elkeold = elkek1ol
Page 309 and 310:
1 2"end of file; go to 13"read(17,*
Page 311 and 312:
4 5"go to 30"noabs(k1mine-k1grd(1,1
Page 313 and 314:
7 8read(17,'(72a1)') bufferread(17,
Page 315 and 316:
subroutine shower(iqi,ei,xi,yi,zi,u
Page 317 and 318:
subroutineuphi(ientry,lvl)Version05
Page 319 and 320:
subroutinerandomset(rndum)Version05
Page 321 and 322:
subroutinerluxinitVersion051219-143
Page 323 and 324:
1i=1i=i+1i>24noyesseeds(i) = real(i
Page 325 and 326:
subroutinerluxinVersion051219-1435w
Page 327 and 328:
Appendix BEGS5 USER MANUALHideo Hir
Page 329 and 330:
Table B.1: Variable descriptions fo
Page 331 and 332:
Page 333 and 334:
Page 335 and 336:
Page 337 and 338:
Table B.12: Variable descriptions f
Page 339 and 340:
Optional parameter modificationsThe
Page 341 and 342:
the call to PEGS5 may be skipped if
Page 343 and 344:
egions. Execution of EGS5 is termin
Page 345 and 346:
of the transport in the walls of el
Page 347 and 348:
call rluxinitafter specifying LUXLE
Page 349 and 350:
END OF FILE ON UNIT 12PROGRAM STOPP
Page 351 and 352:
do i=1,ncasesuf(1)=ufivf(1)=vfiwf(1
Page 353 and 354:
crossed, then USTEP should be set t
Page 355 and 356:
subroutine howfarimplicit noneinclu
Page 357 and 358:
Table B.18: IARG values program sta
Page 359 and 360:
As an example of how to write an AU
Page 361 and 362:
!**********************************
Page 363 and 364:
nreg=3do i=2,nregecut(i)=100.0pcut(
Page 365 and 366:
nlines=0nwrite=15!-----------------
Page 367 and 368:
if (nlines.lt.nwrite) thenwrite(6,1
Page 369 and 370:
Appendix CPEGS USER MANUALHideo Hir
Page 371 and 372:
is entered. On each pass through th
Page 373 and 374:
(from previous figure)(to previous
Page 375 and 376:
(from previous figure)||+ ---------
Page 377 and 378:
+------+|BREMTR|+------+|V+------+|
Page 379 and 380:
+------+|PAIRTR|+------+|V+------+|
Page 381 and 382:
NameDCSLOADDCSSTORDCSTABELASTINOELI
Page 383 and 384:
NameAFFACTAINTPALKEALKEIALINALINIAD
Page 385 and 386:
Table C.5: Functions in PEGS, part
Page 387 and 388:
+------+ +------+ +------+ +------+
Page 389 and 390:
Table C.8: ELEM option input data l
Page 391 and 392:
Table C.10: MIXT option input data
Page 393 and 394:
Table C.12: PWLF option input data
Page 395 and 396:
Table C.17: PLTN option input data
Page 397 and 398:
ICPROF is set to 3, the user must c
Page 399 and 400:
ColumnLine 123456789112345678921234
Page 401 and 402:
interiors of the intervals. If FEXA
Page 403 and 404:
C.3.6The TEST OptionThe TEST option
Page 405 and 406:
C.3.9The HPLT OptionThe Histogram P
Page 407 and 408:
Appendix DEGS5 INSTALLATION GUIDEHi
Page 409 and 410:
egs5 directory (preferably using th
Page 411 and 412:
6. The user is then asked to key-in
Page 413 and 414:
* User code tutor1.f has been compi
Page 415 and 416:
Appendix ECONTENTS OF THE EGS5DISTR
Page 417 and 418:
All of the actual FORTRAN source co
Page 419 and 420:
aprime.data Data for empirical brem
Page 421 and 422:
ismuth krypton silverboron lanthanu
Page 423 and 424:
The tutorial problems and advanced
Page 425 and 426:
Bibliography[1] R. G. Alsmiller Jr.
Page 427 and 428:
[28] A. F. Bielajew. HOWFAR and HOW
Page 429 and 430:
[59] K. Flöttmann. Investigations
Page 431 and 432:
[92] H. Kolbenstvedt. Simple theory
Page 433 and 434:
[123] Y. Namito, H. Hirayama, A. Ta
Page 435 and 436:
[156] Y. A. Shreider, editor. The M
Page 437 and 438:
Index“shower book”, 37AE, 28, 3
Page 439 and 440:
Klein-Nishina formula, 62Landau dis
show all

THE EGS5 CODE SYSTEM

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?