flavio.physics.bdecays.formfactors.b_v.sse module
from math import sqrt import numpy as np from flavio.physics.bdecays.formfactors.common import z def zs(mB, mV, q2, t0): zq2 = z(mB, mV, q2, t0) return np.array([1, zq2, zq2**2]) def pole(ff,mres,q2): mresdict = {'A0': 0,'A1': 2,'A12': 2,'V': 1,'T1': 1,'T2': 2,'T23': 2} m = mres[mresdict[ff]] return 1/(1-q2/m**2) # resonance masses used in BSZ mres_bsz = {} mres_bsz['b->d'] = [5.279, 5.324, 5.716]; mres_bsz['b->s'] = [5.366, 5.414, 5.829]; process_dict = {} process_dict['B->K*'] = {'B': 'B0', 'V': 'K*0', 'q': 'b->s'} process_dict['Bs->phi'] = {'B': 'Bs', 'V': 'phi', 'q': 'b->s'} process_dict['Bs->K*'] = {'B': 'Bs', 'V': 'K*0', 'q': 'b->d'} def ff(process, q2, par, n=2): r"""Central value of $B\to V$ form factors in the lattice convention and simplified series expansion (SSE) parametrization. The lattice convention defines the form factors $A_0$, $A_1$, $A_{12}$, $V$, $T_1$, $T_2$, $T_{23}$. The SSE defines $$F_i(q^2) = P_i(q^2) \sum_k a_k^i \,z(q^2)^k$$ where $P_i(q^2)=(1-q^2/m_{R,i}^2)^{-1}$ is a simple pole. """ pd = process_dict[process] mres = mres_bsz[pd['q']] mB = par['m_'+pd['B']] mV = par['m_'+pd['V']] ff = {} for i in ["A0","A1","A12","V","T1","T2","T23"]: a = [ par[process + ' SSE ' + i.lower() + '_' + 'a' + str(j)] for j in range(n) ] ff[i] = pole(i, mres, q2)*np.dot(a, zs(mB, mV, q2, t0=12.)[:n]) return ff
Module variables
var mres_bsz
var process_dict
Functions
def ff(
process, q2, par, n=2)
Central value of $B\to V$ form factors in the lattice convention and simplified series expansion (SSE) parametrization.
The lattice convention defines the form factors $A_0$, $A_1$, $A_{12}$, $V$, $T_1$, $T_2$, $T_{23}$.
The SSE defines $$F_i(q^2) = P_i(q^2) \sum_k a_k^i \,z(q^2)^k$$ where $P_i(q^2)=(1-q^2/m_{R,i}^2)^{-1}$ is a simple pole.
def ff(process, q2, par, n=2): r"""Central value of $B\to V$ form factors in the lattice convention and simplified series expansion (SSE) parametrization. The lattice convention defines the form factors $A_0$, $A_1$, $A_{12}$, $V$, $T_1$, $T_2$, $T_{23}$. The SSE defines $$F_i(q^2) = P_i(q^2) \sum_k a_k^i \,z(q^2)^k$$ where $P_i(q^2)=(1-q^2/m_{R,i}^2)^{-1}$ is a simple pole. """ pd = process_dict[process] mres = mres_bsz[pd['q']] mB = par['m_'+pd['B']] mV = par['m_'+pd['V']] ff = {} for i in ["A0","A1","A12","V","T1","T2","T23"]: a = [ par[process + ' SSE ' + i.lower() + '_' + 'a' + str(j)] for j in range(n) ] ff[i] = pole(i, mres, q2)*np.dot(a, zs(mB, mV, q2, t0=12.)[:n]) return ff
def pole(
ff, mres, q2)
def pole(ff,mres,q2): mresdict = {'A0': 0,'A1': 2,'A12': 2,'V': 1,'T1': 1,'T2': 2,'T23': 2} m = mres[mresdict[ff]] return 1/(1-q2/m**2)
def zs(
mB, mV, q2, t0)
def zs(mB, mV, q2, t0): zq2 = z(mB, mV, q2, t0) return np.array([1, zq2, zq2**2])