npts = burst_meta['npts']
bg_height = 1047.2220
bg_slope = 0.025935641
start = 44.965676
ampl = 2823.6814
tau1 = 8.1735936
tau2 = 2.2154609
taupk = 48.006471
time = (np.linspace((-nlasc), (npts - nlasc), num=npts) * 0.064) - 2
background = bg_height + bg_slope * time
background = 0 * time
norris_model = burst.draw_norris(time, start, ampl, tau1, tau2, background)
residuals = four_channel_data - norris_model
def chirplet_model(time, start, ampl, tau1, tau2, background):
phi = 0.5
f_0 = 0.28
f_d = -0.01 # anti-chirping stretch
lam = np.exp(2 * np.sqrt(tau1 / tau2))
inten = ampl * lam * np.exp(-tau1 / (time - start) - (time - start) / tau2)
model = inten * (np.cos((2. * np.pi * f_0 * (time - start)) +
(np.pi * f_d * ((time - start) *
(time - start))) + phi))
for i in range(len(time)):
if time[i] <= start:
