6533b82ffe1ef96bd1295a8d

RESEARCH PRODUCT

Evidence for two isospin zeroJ PC=2−+ mesons at 1645 and 1875 MeV

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Data on\(\bar pp \to \eta \pi ^0 \pi ^0 \pi ^0 \) taken at beam momenta of 1.2 and 1.94 GeV/c reveal evidence for twoI=0JPC=2−+ resonances inηππ. The first, at 1645±14(stat.)±15(syst.) MeV with width 180−21+40±25 MeV, decays toα2(1320)π withL=0. It may be interpreted as the\(q\bar q^1 \)D2 partner ofπ2(1670). A strong signal is also observed just above threshold inf2(1270)η withL=0. It is 11–22 times stronger than is expected for the high mass tail of the 1645 MeV resonance. It can be fitted as a second 2−+ resonance at 1875±20±35 MeV with width 200±25±45 MeV. A third resonance havingJPC=2++ is observed at 2135±20±45 MeV withΛ=250±25±45 MeV, decaying to botha2(1320)π andf2(1270)η withL=1. There is no evidence for resonances with decays toa0(980)π, ση orf0(980)η.