def beta_adi(z):
    """
    Losses due to adiabatic expansion. 
    Makes use of the hubble constant converted into units of [yr^-1].
    """
    H0 = 70.4
    H0 = H0 / 3.086e+22 * 1000.0 * 31540000.0
    lCDM = [0.272, 0.728]
    a = lCDM[0] * (1 + z) ** 3
    b = 0
    return H0 * (a + lCDM[1] + b) ** 0.5
