English

The $(\pi^-,\gamma\gamma)$ program at TRIUMF

Nuclear Experiment 2011-07-19 v1

Abstract

We report the first observation of the doubly-radiative decay mode of pionic hydrogen (pi- p --> gamma gamma n) and and deuterium (pi- d --> gamma gamma X) using the RMC pair spectrometer at TRIUMF. The process is interesting in the context of the pi-Compton scattering and the chiPT predictions of the pion polarizability We present our preliminary values for the B.R.(pi- p --> gamma gamma n)=3.8x10^-5 and B.R.(pi- d --> gamma gamma X)=1.6x10^-5. Our pi- p data indicates the dominance of pi pi --> gamma gamma mechanism. The pi- d data shows no evidence for the d1* dibaryon.

Keywords

Cite

@article{arxiv.nucl-ex/0007011,
  title  = {The $(\pi^-,\gamma\gamma)$ program at TRIUMF},
  author = {Piotr A. Zolnierczuk},
  journal= {arXiv preprint arXiv:nucl-ex/0007011},
  year   = {2011}
}

Comments

Talk at MESON'2000 conference in Cracow, Poland (4 pages, 2 figures)