Sigma coupling to photons: hidden scalar in gamma gamma $\to$ pi0 pi0

Pennington, M.R.

doi:10.1103/physrevlett.97.011601

Sigma coupling to photons: hidden scalar in gamma gamma $\to$ pi0 pi0

Pennington, M.R.

Authors

M.R. Pennington

Abstract

There has long been speculation about the nature of the resonance. For three decades Jaffe has argued for a tetraquark composition, while others have claimed it is largely a glueball. A key pointer to its nature is its coupling to two photons. Consequently, there have been recent proposals to observe this important scalar hiding in 00. We show here that the is already crouching in this cross section exactly as measured 20 years ago. What is new is that precise knowledge of the position of the pole, provided by the analysis of the Roy equations, now allows its two photon coupling to be accurately fixed. Its two photon width is found to be (4.1±0.3) keV, a value far too large for a wholly gluonic, or even a tetraquark, state.

Citation

Pennington, M. (2006). Sigma coupling to photons: hidden scalar in gamma gamma $\to$ pi0 pi0. Physical Review Letters, 97(1), https://doi.org/10.1103/physrevlett.97.011601

Journal Article Type	Article
Publication Date	Jul 1, 2006
Deposit Date	Jul 17, 2007
Publicly Available Date	Aug 2, 2010
Journal	Physical Review Letters
Print ISSN	0031-9007
Electronic ISSN	1079-7114
Publisher	American Physical Society
Peer Reviewed	Peer Reviewed
Volume	97
Issue	1
DOI	https://doi.org/10.1103/physrevlett.97.011601