Determination of the quadratic slope parameter in eta -> 3 pi(0) decay - art. no. 192001

Authors
Tippens, WB Prakhov, S Allgower, CE Bekrenev, V Berger, E Briscoe, WJ Clajus, M Comfort, JR Craig, K Efendiev, A Grosnick, D Holstein, BR Huber, GM Isenhower, D Knecht, N Koetke, D Koulbardis, A Kozlenko, N Kruglov, S Lolos, GJ Lopatin, I Manley, DM Marusic, A Manweiler, R McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Phaisangittisakul, N Price, JW Pulver, M Ramirez, AF Sadler, ME Shafi, A Spinka, H Stanislaus, S Starostin, A Staudenmaier, HM
Citation
Wb. Tippens et al., Determination of the quadratic slope parameter in eta -> 3 pi(0) decay - art. no. 192001, PHYS REV L, 8719(19), 2001, pp. 2001
Citations number
15
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
8719
Issue
19
Year of publication
2001
Database
ISI
SICI code
0031-9007(20011105)8719:19<2001:DOTQSP>2.0.ZU;2-X
Abstract
We have determined the quadratic slope parameter alpha for eta -->3 pi (0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta -->3 pi (0) deca ys produced in the reaction pi (-) p -->n mu close to the eta threshold usi ng the Crystal Ball detector at the AGS. The result is four times more prec ise than the present world data and disagrees with current chiral perturbat ion theory calculations by about four standard deviations.