BodyBuilder Errata

A few discrepancies have been noted in previous versions (version 1.21 and lower) of BodyBuilder:

In the 5 year old model, small overlaps were found among the small intestine, ascending color, and transverse colon. The following modified cell descriptions fix the problem

c SMALL INTESTINE
220 1 -1.04 -91 221 -222 223 -7
c                exclude         Transverse Colon
                        (240 :241 :-242 : -232 : -221)
c original                        (240 :241 :-242)
c                exclude         Descending Colon
                        (232:250:-223)
                  vol=   265.00 imp:n,p,e = 1
c
c         ASCENDING COLON
230   1 -1.04       -230 231 -232
                  vol=    47.00 imp:n,p,e = 1
c
c         TRANSVERSE COLON
240   1 -1.04       -240 -241 242 232 221
c original 240   1 -1.04       -240 -241 242
            vol=    61.80 imp:n,p,e = 1
c

The 9 Month pregnant model with no skin references surface 551, but surface 551 is not defined. To Fix, delete surface 551 where it appears in the cell descriptions (or include skin in the model).
An extremely small overlap was found in the transverse colon of the 15 year (adult) female model (it is not known if the problem affects other models). To fix, modify the description of cell 240:
240 1 -1.04 -240 -241 242 -7 221
by adding surfaces -7 and 221.
The newborn transverse colon volume is given as 61.5. The correct value is 6.15.
Importances are written with the incorrect syntax
imp: n,p,e = 1
The correct syntax is
imp:n,p,e = 1
Several cells omit the importance.
The Liver cell description should be:
320 1 -1.04 -320 -321 7 -322 -132
The Liver exclusion for cell 15 should be changed to
#320
instead of
(320:321:322:-7)
The Kidneys and Adrenals slightly overlap in the newborn model. The overlap is prevented by modifying the Kidney cell definition:
310 1 -1.04 (-310 312 -162):(-311 -313 -162)
and similarly when the Kidneys are modeled separate left and right cells. The overlap may be present in other models as well.
The Weight given on the BodyBuilder window is correct. The Weight written to the Statistics comments of the MCNP file is incorrect.
The Height on the BodyBuilder window are the Height written to the MCNP file are incorrect. Both values use A_H (the X radius of the head) instead of C_H2. The value for the window omits C_H0. Both values add the skin thickness S on top and bottom. The top of the head is
C_T + C_H0 + C_H1 + C_H2 + 2S
(C_H0 = 0 in the old head/neck model.)
The Height and Weight are not recalculated immediately when the head/neck model (old or new) is changed.
When viewed in the MCNP geometry plotter with
PY 0
there is an apparent geometry error caused by the viewing plane being coincident with a surface in the model.
To ensure no overlap between the legs, use the following cell descriptions for the legs skin:
34 1 -1.04 (-4 34 -31 36 32):(-31 33 -36 32)
35 1 -1.04 (-4 35 -32 36 31):(-32 33 -36 31)
The sigmoid colon is modeled with 2 torus surfaces. Torii can cause an occasional lost particle in MCNP.
The ZAIDs in the material definitions need to be modified for neutron and/or electron transport.
c SMALL INTESTINE
220 1 -1.04 -91 221 -222 223 -7
C exclude Ascending Colon
(232:230:-223)

Last modified: September, 2004

Kenneth A. Van Riper / email