%0 Journal Article %1 Lansberg2006Twophoton %A Lansberg, J. P. %A Pham, T. N. %D 2006 %K etac, heavy, pheno %T Two-photon width of eta\_c and eta'\_c from Heavy-Quark Spin Symmetry %U http://arxiv.org/abs/hep-ph/0603113 %X We evaluate the two-photon width of the pseudoscalar charmonia, Gamma(eta\_c -> gamma gamma) and Gamma(eta'\_c -> gamma gamma), within a Heavy-Quark Spin-Symmetry setting and show that whereas the former agrees with experiment, the latter is more than twice larger than the recent measurement by CLEO. When binding-energy effects are included in the eta'\_c case, the discrepancy is worse, pointing out at a possible anomaly in the eta'\_c decay.

@article{Lansberg2006Twophoton, abstract = {{We evaluate the two-photon width of the pseudoscalar charmonia, Gamma(eta\_c -\> gamma gamma) and Gamma(eta'\_c -\> gamma gamma), within a Heavy-Quark Spin-Symmetry setting and show that whereas the former agrees with experiment, the latter is more than twice larger than the recent measurement by CLEO. When binding-energy effects are included in the eta'\_c case, the discrepancy is worse, pointing out at a possible anomaly in the eta'\_c decay.}}, added-at = {2019-02-23T22:09:48.000+0100}, archiveprefix = {arXiv}, author = {Lansberg, J. P. and Pham, T. N.}, biburl = {https://www.bibsonomy.org/bibtex/289d77d6cd6695d5998a0d0c393abe840/cmcneile}, citeulike-article-id = {5626872}, citeulike-linkout-0 = {http://arxiv.org/abs/hep-ph/0603113}, citeulike-linkout-1 = {http://arxiv.org/pdf/hep-ph/0603113}, day = 13, eprint = {hep-ph/0603113}, interhash = {5731f5762c5e26b24cd9e6fe9f553a84}, intrahash = {89d77d6cd6695d5998a0d0c393abe840}, keywords = {etac, heavy, pheno}, month = jul, posted-at = {2009-08-23 10:50:30}, priority = {2}, timestamp = {2019-02-23T22:15:27.000+0100}, title = {{Two-photon width of eta\_c and eta'\_c from Heavy-Quark Spin Symmetry}}, url = {http://arxiv.org/abs/hep-ph/0603113}, year = 2006 }