and x and y are coordinates in the x–y plane. Here ℏ ℏ is the reduced Planck constant, e is the electron charge, N is the total number of particles, and B is the magnetic field, which is perpendicular to the xy plane. The subscripts on z identify the particle. In order for the wavefunction to describe fermions, n must be an odd integer. This forces the wavefunction to be antisymmetric under particle interchange. The angular momentum for this state is n ℏ ℏ .