Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1849148 | Physics Letters B | 2015 | 6 Pages |
Abstract
We have studied the vector to pseudoscalar conversion decay ϕ→ηe+e−ϕ→ηe+e−, with η→π0π0π0η→π0π0π0, with the KLOE detector at DAΦ NE. The data set of 1.7 fb−11.7 fb−1 of e+e−e+e− collisions at s∼Mϕ contains a clear conversion decay signal of ∼31,000∼31,000 events from which we measured a value of BR(ϕ→ηe+e−)=(1.075±0.007±0.038)×10−4BR(ϕ→ηe+e−)=(1.075±0.007±0.038)×10−4. The same sample is used to determine the transition form factor by a fit to the e+e−e+e− invariant mass spectrum, obtaining bϕη=(1.28±0.10−0.08+0.09) GeV−2, that improves by a factor of five the precision of the previous measurement and is in good agreement with VMD expectations.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
D. Babusci, I. Balwierz-Pytko, G. Bencivenni, C. Bloise, F. Bossi, P. Branchini, A. Budano, L. Caldeira Balkeståhl, F. Ceradini, P. Ciambrone, F. Curciarello, E. Czerwiński, E. Danè, V. De Leo, E. De Lucia, G. De Robertis, A. De Santis, P. De Simone,