def p_electron(self,
nq,
*,
alpha=1.280,
zeta=0.045,
beta=273 * .9e-4,
gamma=0.0141,
delta=0.062,
drift_field=81):
"""Fraction of detectable NR quanta that become electrons,
slightly adjusted from Lenardo et al.'s global fit
(https://arxiv.org/abs/1412.4417).
Penning quenching is accounted in the photon detection efficiency.
"""
# TODO: so to make field pos-dependent, override this entire f?
# could be made easier...
# prevent /0 # TODO can do better than this
nq = nq + 1e-9
# Note: final term depends on nq now, not energy
# this means beta is different from lenardo et al
nexni = alpha * drift_field**-zeta * (1 - tf.exp(-beta * nq))
ni = nq * 1 / (1 + nexni)
# Fraction of ions NOT participating in recombination
squiggle = gamma * drift_field**-delta
fnotr = tf.math.log(1 + ni * squiggle) / (ni * squiggle)
# Finally, number of electrons produced..
n_el = ni * fnotr
return fd.safe_p(n_el / nq)
def p_electron(nq,
*,
er_pel_a=15,
er_pel_b=-27.7,
er_pel_c=32.5,
er_pel_e0=5.):
"""Fraction of ER quanta that become electrons
Simplified form from Jelle's thesis
"""
# The original model depended on energy, but in flamedisx
# it has to be a direct function of nq.
e_kev_sortof = nq * 13.7e-3
eps = fd.tf_log10(e_kev_sortof / er_pel_e0 + 1e-9)
qy = (er_pel_a * eps**2 + er_pel_b * eps + er_pel_c)
return fd.safe_p(qy * 13.7e-3)
def p_electron(nq, W=13.8e-3, mean_nexni=0.135, q0=1.13, q1=0.47,
gamma_er=0.031 , omega_er=31.):
# gamma_er from paper 0.124/4
F = tf.constant(81.,dtype=fd.float_type())
e_kev = nq * W
fi = 1. / (1. + mean_nexni)
ni, nex = nq * fi, nq * (1. - fi)
wiggle_er = gamma_er * tf.exp(-e_kev / omega_er) * F ** (-0.24)
# delta_er and gamma_er are highly correlated
# F **(-delta_er) set to constant
r_er = 1. - tf.math.log(1. + ni * wiggle_er) / (ni * wiggle_er)
r_er /= (1. + tf.exp(-(e_kev - q0) / q1))
p_el = ni * (1. - r_er) / nq
return fd.safe_p(p_el)