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Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 2
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 3
!
" # x
H
; )*
, -
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J $- K4 C
=$
:
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3 - , =Q4
Compton scattering
4 - O - C$:
Pair production
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%
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Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 5
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 6
2 - ,
- .
)*
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=8
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(Atomic number) ~3 Photoelectric effect
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% -
*
*2 .
Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 7
2 - ,
- .
a X 4=
H )* =KO =
c* V 67 % , - cB * .
* d= ; X 4= ' )* U B 6 . : * V %
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U - 4
*#
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* 4- U 6 `8-\K* ! ( *7 %
F %
; eO G C .
Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 9
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 10
&
,
- .
/0
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H )* =KO =
6
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<-
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&
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 11
3 -
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)
$%&
5 6 7 8 9 : (
) (
0.024(1 cos )
λ θ
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θ
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B
=8 C4 g4U *
C c
% . 4B F O
* B , -
6 B& K 2 6 =8 X 4=
!
\K*
6 B = * -
6 .
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 13
3 -
$%&
2 3*&
, V 67 % cB
= * H
; V %
"
*&
C
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6 B !
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< 9
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B .
C F % F a /hU B
&
5%2 A4B
6 U 4-
* B
=
6 = 9* D-
% i%2 4%
j R2 C B 8 .
Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 14
Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 15
4 -
$
?@A
* 3 %
; 67 O *
`8- J $-
= 4%
.
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= B F - c*7 %
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+
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X 4=
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%
&
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%
&
B ;
*
$
; n =;
B .
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 17
E F B G
e* o _ !h- 6 !
&
C 4
! _ !h- [ -
= `o
!
&
R+ : C
. 67 O *
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µ
µ
E F B G
8!
e* o _ !h-
?;
&
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?;
3 % B ;
9 ( .
Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Dr. H. Pourghassem, 18
Pair Compton ric
Photoelect
Rayleigh µ µ µ
µ
µ= + + +
Department of Electrical Engineering, Najafanad Branch, Islamic Azad University, Dr. H. Pourghassem, 19
E F B C
# A
* e* o
&
g* Y D- e* o _ !h-
?;
= % * Aa O )
( 6 ,2 C ( ) 0 =; C fU 6 *2 C
FR+ :
=%
= b ) ( C .
e* o _ !h- FR2 r*
R2 ` , K*
C O e* o _ !h- :
E%2 . E%2" $= O Aa O C " $= / ;
ρ
µ ρ/
2
g cm ]
)[
( ] )[
] ( [ )
( 3
1 2
cm g g cm
cm ρ
ρ µ µ
−
=
*#
% RS:
% A% 4B
= * 4 % 4U
* _ !h-
! V %
x*#
) C `o (
% RS:
)
Half-value layer(
* .
!*
= `o
&
R+ :
"
! _ % , V
O B
c R2 =% c* &2
x! = _ !h- & % * D . B O !
* 4%
. B ; C
:
0
N=N e−µx
(1) 1000
800 1000 e e
µ µ
= × − = 0.693 0.693
0.22 , 3.15
HVL 0.22 cm
µ µ
⇒ = = = =