European Physical Journal C: Particles and Fields (Apr 2024)

Observation of $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}\gamma $$ K + → π + π 0 π 0 γ decay

  • A. V. Artamonov,
  • V. N. Bychkov,
  • S. V. Donskov,
  • A. P. Filin,
  • S. N. Filippov,
  • A. M. Gorin,
  • E. N. Gushchin,
  • A. V. Inyakin,
  • G. D. Kekelidze,
  • G. V. Khaustov,
  • S. A. Kholodenko,
  • A. A. Khudyakov,
  • V. N. Kolosov,
  • V. I. Kravtsov,
  • Yu. G. Kudenko,
  • A. V. Kulik,
  • V. F. Kurshetsov,
  • V. A. Lishin,
  • V. M. Lysan,
  • M. V. Medynsky,
  • V. F. Obraztsov,
  • A. V. Okhotnikov,
  • V. A. Polyakov,
  • A. Yu. Polyarush,
  • V. I. Romanovsky,
  • V. I. Rykalin,
  • A. S. Sadovsky,
  • V. D. Samoylenko,
  • M. M. Shapkin,
  • I. S. Tiurin,
  • V. A. Uvarov,
  • O. P. Yushchenko,
  • B. Zh. Zalikhanov

DOI
https://doi.org/10.1140/epjc/s10052-024-12674-0
Journal volume & issue
Vol. 84, no. 4
pp. 1 – 6

Abstract

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Abstract The $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}\gamma $$ K + → π + π 0 π 0 γ decay is observed by the OKA collaboration. About 60 events of the decay observed with signal:noise $$\approx 1$$ ≈ 1 . The branching ratio obtained by normalization to $$K^{+} \rightarrow \pi ^{+}\pi ^{0}\pi ^{0}$$ K + → π + π 0 π 0 is measured to be $$(3.7 \pm 0.9(stat) \pm 0.3(syst))\times 10^{-6}$$ ( 3.7 ± 0.9 ( s t a t ) ± 0.3 ( s y s t ) ) × 10 - 6 for $$E_{\gamma }^*>10\,\textrm{MeV}$$ E γ ∗ > 10 MeV . The branching ratio, $$\gamma $$ γ energy spectrum and angular distribution are consistent with ChPT prediction.