Search for a new light gauge boson in decays of π0 and η

C. Amsler, D. S. Armstrong, I. Augustin, C. A. Baker, B. M. Barnett, C. J. Batty, K. Beuchert, P. Birien, P. Blüm, R. Bossingham, K. Braune, J. Brose, D. V. Bugg, M. Burchell, T. Case, A. Cooper, K. M. Crowe, T. Degener, H. P. Dietz, S. von DombrowskiM. Doser, W. Dünnweber, D. Engelhardt, M. Englert, M. A. Faessler, C. Felix, R. Hackmann, R. P. Haddock, F. H. Heinsius, N. P. Hessey, P. Hidas, P. Illinger, D. Jamnik, Z. Jávorfi, H. Kalinowsky, B. Kämmle, T. Kiel, J. Kisiel, E. Klempt, M. Kobel, H. Koch, C. Kolo, K. Königsmann, M. Kunze, R. Landua, F. Loser, J. Lüdemann, H. Matthäy, M. Merkel, J. P. Merlo, C. A. Mever, L. Montanet, A. Noble, F. Ould-Saada, K. Peters, C. N. Pinder, G. Pinter, S. Ravndal, J. Salk, A. H. Sanjari, E. Schäfer, B. Schmid, P. Schmidt, S. Spanier, C. Straßburger, U. Strohbusch, M. Suffert, D. Urner, C. Völcker, F. Walter, D. Walther, U. Wiedner, N. Winter, J. Zoll, B. Zou, Č Zupančič

Research output: Contribution to journalArticle

13 Citations (Scopus)


We have searched for new light gauge bosons produced in π0 and η decays by studying the kinematically well-constrained reactions p ̄p→π0π0π0 and p ̄p→π0π0η, where one π0 or the η decays through the emission of a single photon recoiling against a missing state X (where X is a long-lived weakly interacting particle or X →ν ν ̄). No signal has been observed and branching ratio upper limits of 6 × 10-5 at 90% C.L. have been obtained for masses of the gauge boson lying between ∼65 MeV and 125 MeV (π0 decay), and 6 × 10-5 at 90% C.L. for X masses between ∼200 MeV and 525 MeV (η decay). The π0-decay limit represents a factor of 4 to 8 improvement when compared to the existing limit, whereas the η decay limit has been measured for the first time, thereby extending the mx range from 130 MeV up to 525 MeV.

Original languageEnglish
Pages (from-to)271-276
Number of pages6
JournalPhysics Letters B
Issue number1-2
Publication statusPublished - Jul 28 1994

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Fingerprint Dive into the research topics of 'Search for a new light gauge boson in decays of π<sup>0</sup> and η'. Together they form a unique fingerprint.

  • Cite this

    Amsler, C., Armstrong, D. S., Augustin, I., Baker, C. A., Barnett, B. M., Batty, C. J., Beuchert, K., Birien, P., Blüm, P., Bossingham, R., Braune, K., Brose, J., Bugg, D. V., Burchell, M., Case, T., Cooper, A., Crowe, K. M., Degener, T., Dietz, H. P., ... Zupančič, Č. (1994). Search for a new light gauge boson in decays of π0 and η. Physics Letters B, 333(1-2), 271-276.