def METHOD_NAME(p, t, dataStart):
    """Model for bleach decay when the rate is dominated by dye-dye interactions.
    The equation (~ 1/t) is a solution to a differential equation of the form:
        dN/dt = -k*N^2
    The parameters are:
        A0 - The initial intensity
        k - the rate constant
        b - a constant background
        o - an offset between the parts of the curves taken with different EM gain
    dataStart dictates the start of the protion with high EM gain
    Note that the 1/t curve is shifted to be 1 at t=0."""
    A0, k, b, sc, o = p
    return ((sc - 1)*(t<dataStart) + 1)*A0/(t/k + 1) + b + o*(t<dataStart)