Module flavio.physics.bdecays.blnu

Functions for $B\to\ell\nu$ decays.

Functions

def br_blnu(wc_obj, par, B, lep)

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def br_blnu(wc_obj, par, B, lep):
    return sum([_br_blnu(wc_obj,par,B,lep,nu) for nu in ['e', 'mu', 'tau']])

def br_blnu_fct(B, lep)

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def br_blnu_fct(B, lep):
    def f(wc_obj, par):
        return br_blnu(wc_obj, par, B, lep)
    return f

def br_plnu_general(wc, par, Vij, P, qiqj, lep, nu, mq1, mq2, delta=0)

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def br_plnu_general(wc, par, Vij, P, qiqj, lep, nu, mq1, mq2, delta=0):
    r"""Branching ratio of general $P^+\to\ell^+\nu_\ell$ decay.

    `Vij` is the appropriate CKM matrix element.
    `mq1` and `mq2` are the masses of the two quarks forming the meson $P$.
    `delta` (detaults to 0) is a correction factor to account for different
    experimental treatment of electromagnetic effects, for instance.
    """
    ml = par['m_'+lep]
    mP = par['m_'+P]
    GF = par['GF']
    tau = par['tau_'+P]
    f = par['f_'+P]
    # Wilson coefficient dependence
    qqlnu = qiqj + lep + 'nu' + nu
    rWC = (wc['CVL_'+qqlnu] - wc['CVR_'+qqlnu]) + mP**2/ml/(mq1 + mq2) * (wc['CSR_'+qqlnu] - wc['CSL_'+qqlnu])
    N = tau * GF**2 * f**2 / (8*pi) * mP * ml**2  * (1 - ml**2/mP**2)**2
    return N * abs(Vij)**2 * abs(rWC)**2 * (1 + delta)

Branching ratio of general $P^+\to\ell^+\nu_\ell$ decay.

Vij is the appropriate CKM matrix element. mq1 and mq2 are the masses of the two quarks forming the meson $P$. delta (detaults to 0) is a correction factor to account for different experimental treatment of electromagnetic effects, for instance.