Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8196578 | Physics Letters B | 2007 | 6 Pages |
Abstract
We present new precision measurements of the Ï(2S) total and partial widths from excitation curves obtained in antiproton-proton annihilations by Fermilab experiment E835 at the Antiproton Accumulator in the year 2000. A new technique of complementary scans was developed to study narrow resonances with stochastically cooled antiproton beams. The technique relies on precise revolution-frequency and orbit-length measurements, while making the analysis of the excitation curve almost independent of machine lattice parameters. We study the Ï(2S) meson through the processes p¯pâe+eâ and p¯pâJ/Ï+Xâe+eâ+X. We measure the width to be Î=290±25(sta)±4(sys)keV and the combination of partial widths Îe+eâÎp¯p/Î=579±38(sta)±36(sys)meV, which represent the most precise measurements to date.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
Fermilab E835 Collaboration Fermilab E835 Collaboration, M. Andreotti, S. Bagnasco, W. Baldini, D. Bettoni, G. Borreani, A. Buzzo, R. Calabrese, R. Cester, G. Cibinetto, P. Dalpiaz, G. Garzoglio, K.E. Gollwitzer, M. Graham, M. Hu, D. Joffe, J. Kasper,