Tau decay into $$\nu _\tau $$ and $$a_1(1260)$$, $$b_1(1235)$$, and two $$K_1(1270)$$

Abstract

AbstractWe study the $$\tau \rightarrow \nu _\tau A$$τ→ντA decay, with A an axial-vector meson. We produce the $$a_1(1260)$$a1(1260) and $$b_1(1235)$$b1(1235) resonances in the Cabibbo favored mode and two $$K_1(1270)$$K1(1270) states in the Cabibbo suppressed mode. We take advantage of previous chiral unitary approach results where these resonances appear dynamically from the vector and pseudoscalar meson interaction in s-wave. Actually two different poles were obtained associated to the $$K_1(1270)$$K1(1270) quantum numbers. We find that the unmeasured rates for $$b_1(1235)$$b1(1235) production are similar to those of the $$a_1(1260)$$a1(1260) and for the two $$K_1$$K1 states we suggest to separate the present information on the $$\bar{K} \pi \pi $$K¯ππ invariant masses into $$\bar{K}^* \pi $$K¯∗π and $$\rho K$$ρK modes, the channels to which these two resonances couple most strongly, predicting that these modes peak at different energies and have different widths. These measurements should shed light on the existence of these two $$K_1$$K1 states. In addition, we have gone one step further making a comparison with experimental results of three meson decay channels, letting the vector mesons of our approach decay into pseudoscalars, and we find an overall good agreement with experiment.