irpa 11 guidelines for authors on the preparation of the full papers

First, in order to acquire the characteristic of the glass dosimeter which equipping with a filter of
uni<strong>for</strong>m thickness, a basic model which covered the reading portion of the glass element with a
uni<strong>for</strong>m thickness filter of Sn in the range of 0-0.75 mm was created, and this model was included in
the EGS4 code <strong>for</strong> per<strong>for</strong>ming a photon irradiation simulation. Next, the simulation which irradiates
monochromatic photons in the range of 0.01-10 MeV to the model was carried out, and the amount of
energy absorption in the dose reading portion of the glass element was calculated. The characteristic of
this model was obtained by breaking that absorption energy by the air Kama. This operation was
carried out to the other model to which the thickness of Sn filter was changed, and some different
characteristic curves were collected. These characteristic curves were used <strong>for</strong> the development of a
practical filter model which gives a new characteristic required <strong>for</strong> the measurement of an effective
dose or a dose equivalent. The new characteristic was calculated by the method of weight averaging
those characteristics with the suitable coefficients defined experientially. The coefficients were used
<strong>for</strong> the design of the practical filter, and determined the area of each part of a filter which covers the
dose reading part of the glass element. The glass dosimeter equipped with the new designed filter was
built into the EGS4 code, and it was examined whether the characteristic of the glass element shows
the target characteristic.
2.3. Acquisition of the basic characteristic data based on a simulation
The glass dosimeter model which equipped with the filter of uni<strong>for</strong>m thickness as shown in the
following Figure 1 was created into the EGS4 code. Then, 100 million photons were equally irradiated
from the 2 m away point of the model sides to the area of 3x3 cm 2 centering on the model, the energy
absorption characteristic of the glass element was acquired <strong>for</strong> 42 kinds of photon energy in the range
of 0.01~10MeV. Moreover, nine kinds of thickness of a tin (Sn) filter was gradually changed with 0,
0.1, 0.2,..., 0.7, and 0.75 mm, and the characteristic fi(x) (i=1to9) about each case was calculated,
respectively. Where, x is photon energy of a MeV unit.
Sn
Sn
dose reading domain
Sn
hν hν
Sn
ABS
ID No.
glass element
Fig.1.A composition figure of a basic model (the right is a short axis section and the left is a long axis
section.), and photon irradiation.
2.4. Composition of the characteristic corresponding to an effective dose or the dose equivalent
The nine characteristics fi(x) (i=1 to 9) were multiplied by the coefficients ki and a new characteristic
F(x) was compounded from those sums, as shown in following equation.
F(x)=k1f1(x)+k2f2(x)+ +k9f9(x) ---------- (1)
where, k1, k2, , k9 were load coefficients which determined experientially and required <strong>for</strong>
obtaining the new characteristic suited to an effective dose or a dose equivalent. The sum total of ki
2
Sn