New measurement of the decay branching ratio and hadronic form factors

Batley, J. R.; Kalmus, G.; Lazzeroni, C.; Munday, D. J.; Slater, M. W.; Wotton, S. A.; Arcidiacono, R.; Bocquet, G.; Cabibbo, N.; Ceccucci, A.; Cundy, D.; Falaleev, V.; Fidecaro, M.; Gatignon, L.; Gonidec, A.; Kubischta, W.; Norton, A.; Maier, A.; Patel, M.; Peters, A.; Balev, S.; Frabetti, P. L.; Gersabeck, E.; Goudzovski, E.; Hristov, P.; Kekelidze, V.; Kozhuharov, V.; Litov, L.; Madigozhin, D.; Molokanova, N.; Polenkevich, I.; Potrebenikov, Y. u.; Stoynev, S.; Zinchenko, A.; Monnier, E.; Swallow, E.; Winston, R.; Rubin, P.; Walker, A.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Damiani, C.; Fiorini, M.; Gianoli, A.; Martini, M.; Petrucci, F.; Savrié, M.; Scarpa, M.; Wahl, H.; Bizzeti, A.; Lenti, M.; Veltri, M.; Calvetti, Mario; Iacopini, Enrico; Ruggiero, G.; Behler, M.; Eppard, K.; Kleinknecht, K.; Marouelli, P.; Masetti, L.; Moosbrugger, U.; Morales Morales, C.; Renk, B.; Wache, M.; Wanke, R.; Winhart, A.; Coward, D.; Dabrowski, A.; Fonseca Martin, T.; Shieh, M.; Szleper, M.; Velasco, M.; Wood, M. D.; Cenci, P.; Pepe, M.; Petrucci, M. C.; Anzivino, G.; Imbergamo, E.; Nappi, A.; Piccini, M.; Raggi, M.; Valdata Nappi, M.; Cerri, C.; Fantechi, R.; Collazuol, G.; Dilella, L.; Lamanna, G.; Mannelli, I.; Michetti, A.; Costantini, F.; Doble, N.; Fiorini, L.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Bloch Devaux, B.; Cheshkov, C.; Chèze, J. B.; De Beer, M.; Derré, J.; Marel, G.; Mazzucato, E.; Peyaud, B.; Vallage, B.; Holder, M.; Ziolkowski, M.; Biino, C.; Cartiglia, N.; Marchetto, F.; Bifani, S.; Clemencic, M.; Goy Lopez, S.; Dibon, H.; Jeitler, M.; Markytan, M.; Mikulec, I.; Neuhofer, G.; Widhalm, L.

doi:10.1016/j.physletb.2012.07.048

Abstract: A sample of more than one million K-+/- -> pi(+)pi(-)e(+/-)v (K-e4) decay candidates with less than one percent background contamination has been collected by the NA48/2 experiment at the CERN SPS in 2003-2004, allowing a detailed study of the decay properties. The branching ratio, inclusive of K-e4 gamma decays, is measured to be BR(K-e4) = (4.257 +/- 0.016(exp) +/- 0.031(ext)) x 10(-5) with a total relative error of 0.8%. This measurement complements the study of S- and P-wave hadronic form factors by assigning absolute values to the relative hadronic form factors obtained earlier in a simultaneous analysis of the pi pi scattering lengths conducted on the same data sample. The overall form factor normalization f(s) = 5.705 +/- 0.017(exp) +/- 0.031(ext) is obtained with a total relative precision of 0.6%.

New measurement of the decay branching ratio and hadronic form factors / J.R. Batley;G. Kalmus;C. Lazzeroni;D.J. Munday;M.W. Slater;S.A. Wotton;R. Arcidiacono;G. Bocquet;N. Cabibbo;A. Ceccucci;D. Cundy;V. Falaleev;M. Fidecaro;L. Gatignon;A. Gonidec;W. Kubischta;A. Norton;A. Maier;M. Patel;A. Peters;S. Balev;P.L. Frabetti;E. Gersabeck;E. Goudzovski;P. Hristov;V. Kekelidze;V. Kozhuharov;L. Litov;D. Madigozhin;N. Molokanova;I. Polenkevich;Yu. Potrebenikov;S. Stoynev;A. Zinchenko;E. Monnier;E. Swallow;R. Winston;P. Rubin;A. Walker;W. Baldini;A. Cotta Ramusino;P. Dalpiaz;C. Damiani;M. Fiorini;A. Gianoli;M. Martini;F. Petrucci;M. Savrié;M. Scarpa;H. Wahl;A. Bizzeti;M. Lenti;M. Veltri;M. Calvetti;E. Iacopini;G. Ruggiero;M. Behler;K. Eppard;K. Kleinknecht;P. Marouelli;L. Masetti;U. Moosbrugger;C. Morales Morales;B. Renk;M. Wache;R. Wanke;A. Winhart;D. Coward;A. Dabrowski;T. Fonseca Martin;M. Shieh;M. Szleper;M. Velasco;M.D. Wood;P. Cenci;M. Pepe;M.C. Petrucci;G. Anzivino;E. Imbergamo;A. Nappi;M. Piccini;M. Raggi;M. Valdata-Nappi;C. Cerri;R. Fantechi;G. Collazuol;L. DiLella;G. Lamanna;I. Mannelli;A. Michetti;F. Costantini;N. Doble;L. Fiorini;S. Giudici;G. Pierazzini;M. Sozzi;S. Venditti;B. Bloch-Devaux;C. Cheshkov;J.B. Chèze;M. De Beer;J. Derré;G. Marel;E. Mazzucato;B. Peyaud;B. Vallage;M. Holder;M. Ziolkowski;C. Biino;N. Cartiglia;F. Marchetto;S. Bifani;M. Clemencic;S. Goy Lopez;H. Dibon;M. Jeitler;M. Markytan;I. Mikulec;G. Neuhofer;L. Widhalm. - In: PHYSICS LETTERS. SECTION B. - ISSN 0370-2693. - STAMPA. - 715:(2012), pp. 105-115. [10.1016/j.physletb.2012.07.048]