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CS (Fig. 2,
b
) the laws of conservation for an elementary scattering action
will take the form of:
~
ω
0
+
~
ω
=
~
ω
0
;
~
~k
0
+
~
~k
=
~
~k
0
.
The Stokes process of exciting radiation photon decay into an axion and
a virtual photon of the magnetic field becomes possible in the elementary
CS process during the photon-axion conversion in a constant external
alternating magnetic field (Fig. 2). In the anti-Stokes process a “collision”
of the exciting radiation photon with the photon of the external magnetic
field occurs, resulting in generating an axion – the low energy pseudoscalar
boson (Fig. 2,
c, d
). If the magnetic field is alternating, the virtual photons
relating to the external magnetic field are the real particles and are
characterized by the frequencies of the alternating magnetic field.
For the Stokes and anti-Stokes processes of the photon-axion conversion,
the laws of conservation will consequently take the form of:
~
ω
0
=
~
ω
0
+
~
ω
;
~
~k
0
(
γ
) =
~
~k
0
(
b
) +
~
~k
(
m
);
(2)
~
ω
0
+
~
ω
=
~
ω
0
;
~
~k
0
(
γ
) +
~
~k
(
m
) =
~
~k
0
(
b
)
.
(3)
If the external magnetic field is constant, the relations (2), (3) become
simpler and are transformed into:
~
ω
0
=
~
ω
0
;
~
~k
0
(
γ
) =
~
~k
0
(
b
)
.
(4)
The inverse process — the reconversion of axions into photons — is also
possible (Fig. 2,
d
). In this case the Stokes and anti-Stokes processes are
possible, for which the following relations are used:
~
ω
0
=
~
ω
0
+
~
ω
;
~
~k
0
(
b
) =
~
~k
0
(
γ
) +
~
~k
(
m
)
.
If the external magnetic field is constant, then:
~
ω
0
=
~
ω
0
;
~
~k
0
(
b
) =
~
~k
0
(
γ
)
.
(5)
Thus, the processes of photon-axion conversion and reconversion in
a magnetic field are similar to the processes of the Stokes CS and anti-
Stokes CS in crystals. If in the field of the scattered radiation inside a
crystal, active for the CS, there are
n
s
light quanta of CS per one mode of
ISSN 1812-3368. Herald of the BMSTU. Series “Natural Sciences”. 2014. No. 6
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