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Decays of baryon resonances in the second and the third resonance region into N pi0 pi0 are studied by photoproduction of two neutral pions off protons. Partial decay widths of N* and Delta* resonances decaying into Delta(1232) pi, N(pipi)_{S}, N(1440)P_{11} pi, and N(1520)D_{13} pi are determined in a partial wave analysis of this data, and data from other reactions. Several partial decay widths were not known before. Interesting decay patterns are observed which are not even qualitatively reproduced by quark model calculations. In the second resonance region, decays into Delta(1232) pi dominate clearly. The N(pipi)_{S}-wave provides a significant contribution to the cross section, especially in the third resonance region. The P_{13}(1720) properties found here are at clear variance to PDG values.
Preliminary results on the study of e+e- --> phi(1020) --> pi0 pi0 gamma, eta pi0 gamma processes from SND experiment at VEPP-2M collider in Novosibirsk are presented. Branching ratios of rare radiative phi --> pi0 pi0 gamma and phi --> pi0 eta gamma
Angular distributions in the final state of pi0-eta photoproduction on nucleons are considered. As a formal base the familiar isobar model is used in which the (pi0 eta N) state is a product of the resonance decay into eta-Delta(1232) and pi-S_{11}(1
Evidence has recently been presented for the existence of a dibaryon of mass 2380 MeV/c^2 and width 70 MeV/c^2, which decays strongly into the d pi0 pi0 channel [M. Bashkanov et al., Phys.Rev.Lett. 102 (2009) 052301; P. Adlarson et al., arXiv:1104.01
The reaction gamma p -> p pi0 gamma has been measured with the Crystal Ball / TAPS detectors using the energy-tagged photon beam at the electron accelerator facility MAMI-B. Energy and angular differential cross sections for the emitted photon gamma
Coherent photoproduction of two neutral pions on the deuteron and ^3He is calculated. The isoscalar and isovector parts of the elementary photoproduction amplitude was determined by fitting the measured total cross section on protons and neutrons. Th