In view of the recent measurement of the \(F_L^{D^*}\) magnitude in the \({\bar{B}} \rightarrow D^{*} {\bar{\nu }}_\tau \tau \) reaction we evaluate this magnitude within the standard model and for a family of models with the \(\gamma ^\mu -\alpha \gamma ^\mu \gamma _5\) current structure for the quarks for different values of \(\alpha \). At the same time we evaluate also the transverse contributions, \(M=-1\), \(M=+1\), and find that the difference between the \(M=-1\) and \(M=+1\) contributions is far more sensitive to changes in \(\alpha \) than the longitudinal component. These findings should be looked as an incentive to measure the transverse helicities which are bound to be a far more sensitive magnitude to possible new physics than \(F_L^{D^*}\).

中文翻译：

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$ {\ bar {B}} \ rightarrow D ^ {** {\ bar {\ nu}} _ \ tau \ tau $$ B’→D ∗ν¯ττ衰减中的螺旋度，随着夸克中VA的破坏部门

鉴于最近对\（{\ bar {B}} \ rightarrow D ^ {*} {\ bar {\ nu}} _ \ tau \\ （F_L ^ {D ^ *} \）量级的测量tau \）反应，我们针对标准夸克的不同值，在标准模型和具有\（\ gamma ^ \ mu-\ alpha \ gamma ^ \ mu \ gamma _5 \）当前结构的一系列模型中评估此幅度。 （\ alpha \）。同时，我们还评估了横向贡献\（M = -1 \），\（M = + 1 \），并且发现\（M = -1 \）与\（M = + 1 \）贡献对\（\ alpha \）的变化更加敏感比纵向分量大。这些发现应被视为激励测量横向螺旋，这些横向螺旋势必比\（F_L ^ {D ^ *} \）对可能的新物理学更为敏感。