Measurement of the branching ratios for the decays tau -> hadron pi0 nu and tau -> hadron pi0 pi0 nu

Antreasyan, D.; Bartels, H. W.; Besset, D.; Bieler, C. h.; Bienlein, J. K.; Bizzeti, Andrea; Bloom, E. D.; Brock, I.; Brockmüller, K.; Cabenda, R.; Cartacci, A.; Cavalli Sforza, M.; Clare, R.; Compagnucci, A.; Conforto, G.; Cooper, S.; Cowan, R.; Coyne, D.; Engler, A.; Fairfield, K.; Folger, G.; Fridman, A.; Gaiser, J.; Gelphman, D.; Glaser, G.; Godfrey, G.; Graaf, K.; Heimlich, F. H.; Heinsius, F. H.; Hofstadter, R.; Irion, J.; Jakubowski, Z.; Janssen, H.; Karch, K.; Keh, S.; Kiel, T.; Kilian, H.; Kirkbride, I.; Kloiber, T.; Kobel, M.; Koch, W.; König, A. C.; Königsmann, K.; Krämer, R. W.; Krüger, S.; Landi, G.; Lee, R.; Leffler, S.; Lekebusch, R.; Litke, A. M.; Lockman, W.; Lowe, S.; Lurz, B.; Marlow, D.; Marsiske, H.; Maschmann, W.; Mcbride, P.; Meyer, H.; Muryn, B.; Messing, F.; Metzger, W. J.; Monteleoni, B.; Nernst, R.; Niczyporuk, B.; Nowak, G.; Peck, C.; Pelfer, P. G.; Pollock, B.; Porter, F. C.; Prindle, D.; Ratoff, P.; Reidenbach, M.; Renger, B.; Rippich, C.; Scheer, M.; Schmitt, P.; Schotanus, J.; Schütte, J.; Schwarz, A.; Sievers, D.; Skwarnicki, T.; Stock, V.; Strauch, K.; Strohbusch, U.; Tompkins, J.; Trost, H. J.; van Uitert, B.; Van de Walle, R. T.; Vogel, H.; Voigt, A.; Volland, U.; Wachs, K.; Wacker, K.; Walk, W.; Wegener, H.; Williams, D. A.; Zschorsch, P.

doi:10.1016/0370-2693(91)90161-I

The Crystal Ball detector at the DORIS II storage ring at DESY has been used to measure the branching ratios for the decay modes tau+- -> h+- pi0 nu and tau+- -> h+- pi0 pi0 nu, where h+- is any charged hadron. The results are BR( tau+- -> h+- pi0 nu) = (22.0±0.8±1.9)%, BR( tau+- -> h+- pi0 pi0 nu) = (5.7±0.5 -1.0 +1.7)%. The first result is in good agreement with the present world average. The decay mode h+- pi0 pi0 nu is reconstructed in tau decays for the first time. Its branching ratio, however, is somewhat lower than the corresponding world average, and therefore tends to increase the one-prong problem.

Measurement of the branching ratios for the decays tau -> hadron pi0 nu and tau -> hadron pi0 pi0 nu / D., Antreasyan; H. W., Bartels; D., Besset; Bieler, C. h.; J. K., Bienlein; Bizzeti, Andrea; E. D., Bloom; I., Brock; K., Brockmüller; R., Cabenda; A., Cartacci; M., Cavalli Sforza; R., Clare; A., Compagnucci; G., Conforto; S., Cooper; R., Cowan; D., Coyne; A., Engler; K., Fairfield; G., Folger; A., Fridman; J., Gaiser; D., Gelphman; G., Glaser; G., Godfrey; K., Graaf; F. H., Heimlich; F. H., Heinsius; R., Hofstadter; J., Irion; Z., Jakubowski; H., Janssen; K., Karch; S., Keh; T., Kiel; H., Kilian; I., Kirkbride; T., Kloiber; M., Kobel; W., Koch; A. C., König; K., Königsmann; R. W., Krämer; S., Krüger; G., Landi; R., Lee; S., Leffler; R., Lekebusch; A. M., Litke; W., Lockman; S., Lowe; B., Lurz; D., Marlow; H., Marsiske; W., Maschmann; P., Mcbride; H., Meyer; B., Muryn; F., Messing; W. J., Metzger; B., Monteleoni; R., Nernst; B., Niczyporuk; G., Nowak; C., Peck; P. G., Pelfer; B., Pollock; F. C., Porter; D., Prindle; P., Ratoff; M., Reidenbach; B., Renger; C., Rippich; M., Scheer; P., Schmitt; J., Schotanus; J., Schütte; A., Schwarz; D., Sievers; T., Skwarnicki; V., Stock; K., Strauch; U., Strohbusch; J., Tompkins; H. J., Trost; B., van Uitert; R. T., Van de Walle; H., Vogel; A., Voigt; U., Volland; K., Wachs; K., Wacker; W., Walk; H., Wegener; D. A., Williams; P., Zschorsch. - In: PHYSICS LETTERS. SECTION B. - ISSN 0370-2693. - STAMPA. - 259:(1991), pp. 216-224. [10.1016/0370-2693(91)90161-I]