福格特函數(Voigt functions)是一種在天體物理學、等離子物理學、中子散射、激光光譜學等學科中常見的特殊函數,分為福格特U函數和福格特V函數兩種,定義如下
U ( x , t ) = 1 4 ∗ π ∗ t {\displaystyle U(x,t)={\frac {1}{\sqrt {4*\pi *t}}}} ∫ − ∞ ∞ {\displaystyle \int _{-\infty }^{\infty }} e x p ( − ( x − y ) 2 / 4 t ) 1 + y 2 d y {\displaystyle {\frac {exp(-(x-y)^{2}/4t)}{1+y^{2}}}dy}
V ( x , t ) = 1 4 ∗ π ∗ t {\displaystyle V(x,t)={\frac {1}{\sqrt {4*\pi *t}}}} ∫ − ∞ ∞ {\displaystyle \int _{-\infty }^{\infty }} y e x p ( − ( x − y ) 2 / 4 t ) 1 + y 2 d y {\displaystyle y{\frac {exp(-(x-y)^{2}/4t)}{1+y^{2}}}dy}
Frank Oliver,NIST Handbook of Mathematical Functions, p167-168,Cambridge University Press 2010