filled in completely and constitutes an area (fig. 6).
yae needs
the present dose response curve RSE
in principle @ separate,
enrirtcally deterintned “cutve™,
¢
*y
fallacy and fucility of
This
agent cacrlers (particles) of every ccaceivirie type and energy so that aay
venerality of
made
the RBE concept is
in order for
The fact
additional variaole
Thac ts
requiced.
This
keV um) ig
or,
is
to say,
tissues.
irea also indicates
the
three-dinensiconal plot tn Fiz. 3 ts
varlable
has
been
tnoughe
to
be
LET,
expresse: us
Such a continuous function, representec by a gr3up
the curve representing
is presented in Fig. 3a.
been well appreciated
ire
the mean of a segment of the
The separated points represent
in radtattion protection, assigned values of Q.
clear from
thac an
involved as well as an unexpressec continuous
missing
‘separated points on
curve,
~silo
the system to be workatle at all.
that the curves can f{li an
function.
Thusce severe contramuises
Lllusur:.
that LET is nut adequate
the A=
However, {it has icng
fur the purpose.
It i3
the above discussion that this missing function ts not LET, in
the sense of
transfer of energy to tissues.
specific~-to
the cell TCV,
Rather,
to constitute cell dose.
the
transfer is quite
Thus high- ang isw=LivT
radiacions are in fact large- and small cell dose radiations.
High-Level Exposure
In the above discussion, exposure
discussed.
to luw-LzT radtation only was
The differences between lew- and hign-LET radiations are shown
for a low-LET racta fon only.
cr
in Figure 7,
Flott<d on
exposuce, expressed in units of Ny/Nh ze or 2,.
is
the mean hit size,
figure.
On
On the left orcinate
the number of discrete hits per cell,
to the straight diagonal line,
curve for the mean hit size.
S00 THb 3
tre
corresponding to the heavy curved line shown in the
the right ordinate is
corresponding
the siscissa 13
22
part of which overlaps we