$BC10LGHD9$"$?$j$N>e8~$-5Z$S2<8~$-J|<MB+L)EY$O(B, $B0J2<$N$h$&$KDj5A$5$l$k(B.
\begin{eqnarray}
 F_{\nu }^{\uparrow }&=& \int _{2\pi }I_{\nu }^{\uparrow }(\theta )
\cos \theta \Dd \omega \Deqlab{eq: 2.1} \\
 F_{\nu }^{\downarrow }&=& \int _{2\pi }I_{\nu }^{\downarrow }(\psi )
\cos \psi \Dd \omega \Deqlab{eq: 2.2}
\end{eqnarray}
$BJ|<M6/EY(B $I_{\nu }^{\uparrow }(\theta ), I_{\nu }^{\downarrow }
(\psi )$ $B$K3QEYJ}8~$KJ?6Q$7$?CM(B $ I_{\nu }^{\uparrow }, 
I_{\nu }^{\downarrow }$ 
\[
 I_{\nu }^{\uparrow }=\int _{2\pi }I_{\nu }^{\uparrow }\frac{\Dd \omega }{
2\pi },\;  I_{\nu }^{\downarrow }=\int _{2\pi }I_{\nu }^{\downarrow }
\frac{\Dd \omega }{2\pi }
\]
$B$rMQ$$$k$H(B, 
\begin{eqnarray}
 F_{\nu }^{\uparrow }&=& I_{\nu }^{\uparrow }\int _{2\pi }
\cos \theta \Dd \omega \nonumber \\
&=& 2\pi I_{\nu }^{\uparrow }\int _{0}^{\pi /2}\cos \theta \sin \theta \Dd 
\theta = \pi I_{\nu }^{\uparrow } \Deqlab{eq: 2.3} \\
 F_{\nu }^{\downarrow }&=& \int _{2\pi }I_{\nu }^{\downarrow }(\psi )
\cos \psi \Dd \omega \nonumber \\
&=& 2\pi I_{\nu }^{\downarrow } \int _{0}^{\pi /2}\cos \psi \sin \psi \Dd \psi
= \pi I_{\nu }^{\downarrow } \Deqlab{eq: 2.4}
\end{eqnarray}
$B$H$J$k(B.
$B$h$C$F3QEYJ}8~$KJ?6Q$7$?J|<MEAC#J}Dx<0(B
\begin{eqnarray*}
 \frac{2}{3}\DD{I_{\nu }^{\uparrow }}{\tau _{\nu }}
&=& I_{\nu }^{\uparrow }-B_{\nu } \\
 \frac{2}{3}\DD{I_{\nu }^{\downarrow }}{\tau _{\nu }}
&=& -I_{\nu }^{\downarrow }+B_{\nu }
\end{eqnarray*}
$B$NN>JU$K(B $\pi $ $B$r$+$1$k$3$H$G(B, $BJ|<MB+L)EY$NJ}Dx<0$K$9$k$3$H$,$G$-$k(B.
$B$9$J$o$A(B, 
\begin{eqnarray}
 \frac{2}{3}\DD{F_{\nu }^{\uparrow }}{\tau _{\nu }}
&=& F_{\nu }^{\uparrow }-\pi B_{\nu } \Deqlab{eq: 2.5} \\
 \frac{2}{3}\DD{F_{\nu }^{\downarrow }}{\tau _{\nu }}
&=& -F_{\nu }^{\downarrow }+\pi B_{\nu }\Deqlab{eq: 2.6}
\end{eqnarray}
$B2r$O(B
\begin{eqnarray}
 F_{\nu }^{\uparrow }(\tau _{\nu })&=&F_{\nu }^{\uparrow }(\tau _{\nu b})
e^{\frac{3}{2}(\tau _{\nu }-\tau _{\nu b})}+\int _{\tau _{\nu }}^
{\tau _{\nu b}}\frac{3}{2}\pi B_{\nu } e^{-\frac{3}{2}(\tau _{\nu }'-
\tau _{\nu })}\Dd \tau _{\nu }' \Deqlab{eq: 2.7} \\
 F_{\nu }^{\downarrow }(\tau _{\nu })&=&F_{\nu }^{\downarrow }(0)
e^{-\frac{3}{2}\tau _{\nu }}+\int _{0}^{\tau _{\nu }}\frac{3}{2}\pi B_{\nu }
e^{\frac{3}{2}(\tau _{\nu }'-\tau _{\nu })}\Dd \tau _{\nu }' \Deqlab{eq: 2.8}
\end{eqnarray}
$B$H$J$k(B.





