k=2πσ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiWacmWacmaadaGadeaabaGaaqaaaOqaaiaadUgacqGH9aqpju gqbiaaikdaimaakiab=b8aWjabeo8aZbaa@3C44@
Note 1 to entry: The angular wavenumber is the magnitude of the wave vector.