Model for anomalous Υ'' → Υππ transition with account of chiral phase shift in hadron bag of quarkonium

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We assume that a rather large bag of the Υ''(3S b b) heavy quarkonium is in the phase of spontaneously broken chiral symmetry, in contrast to the Υ(1S b b) hadron bag, having small size and being in the phase of exact chiral symmetry, so that the shift of the phases in the Υ'' → Υππ transition is the additional source for the ππ pairs. This source causes an anomalous ππ invariant mass distribution, which is experimentally observed.