Summary
The K l3 form factorsf ±(t) are obtained by means of current algebra dispersive sum rules. After introducing a simple Veneziano formula with satellites for the relevant amplitudes, and using the normalizationf +(0)=1, an expression with no free parameters is found for bothf ±(0). In the decay region they turn out to bef +(t)=1+0.06(t/m 2π ),f −(t)=−1.7(1+0.02(t/m 2π ). Thus, the model predicts the following values for the Kl3 parameters: ξ(0)=−1.7, λ+=0.06, λ−=0.02 andΛ=0.07. The agreement with experiment is found to be excellent.
Riassunto
Si ottengono i fattori di formaf ±(t) di K l3 per mezzo di regole di somma dispersive dell’algebra delle correnti. Dopo aver introdotto una semplice formula di Veneziano per le pertinenti ampiezze, ed usando la normalizzazionef +(0)=1, si trova perf ±(0) un’espressione senza parametri liberi. Nella regione del decadimento esse risultano esseref +(t)=1+0.06(t/m 2π ),f −(t)=−1.7(1+0.02(t/m 2π )). Così il modello predice i seguenti valori dei parametri di K l3: ξ(0)=−1.7, λ+=0.06, λ−=0.02 eΛ=0.07. Si trova che la concordanza con i dati sperimentali è eccellente.
Реэюме
С помошью дисперсионных правил сумм алгебры токов находятся K l3 форм-факторыf ±(). После введения простой формулы Венециано с сателлитами для соответствуюших амплитуд и испольэуя нормировкуf +(0)=1, мы получаем дляf ±(t) выражения, не содержашие параметров. В области распада зти выражения имеют вид
. Таким обраэом, зта модель предскаэывает следуюшие величины для K l3 параметров: ξ(0)=−1.7, λ+=0.06, λ−=0.02 иЛ=0.07. Получается хорощее согласие с зкспериментом.
Similar content being viewed by others
References
R. Jengo andE. Remiddi:Nucl. Phys.,15 B, 1 (1970).
C. A. Domínguez andO. Zandrón:Nuovo Cimento,3 A, 298 (1971).
C. A. Domínguez andO. Zandrón:Nucl. Phys.,33 B, 303 (1971).
G. Veneziano:Nuovo Cimento,57 A, 190 (1968).
D. Sivers andJ. Yellin: Berkeley preprint, UCRL-19418, and references cited therein.
S. Fubini:Nuovo Cimento,43 A, 475 (1966).
V. de Alfaro, S. Fubini, C. Rossetti andG. Furlan:Ann. of Phys.,44, 165 (1967).
G. E. Hite:Rev. Mod. Phys.,41, 669 (1969).
For another approach see ref. (9).
Fayyazuddin andRiazuddin:Ann. of Phys.,55, 131 (1969).
K. Kawarabayashi, S. Kitakado andH. Yabuki:Phys. Lett.,28 B, 432 (1969).
M. Ademollo andR. Gatto:Phys. Rev. Lett.,13, 264 (1965).
Due to the huge number of both theoretical and experimental papers on K l3 form factors, we refer to the excellent reviews, ref. (12,13), where an exhaustive list of references can be found.
M. K. Gaillard andL. M. Chounet: CERN preprint, CERN 70-14 (1970).
M. K. Gaillard: CERN preprint, CENR-TH. 1292 (1971).
Author information
Authors and Affiliations
Additional information
Work supported in part by the U.S. Atomic Energy Commission.
Fellow from the University of Buenos Aires.
Rights and permissions
About this article
Cite this article
Domínguez, C.A., Zandrón, O.S. Current algebra sum rules, veneziano model and K l3 form factors. Nuov Cim A 11, 13–22 (1972). https://doi.org/10.1007/BF02722774
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02722774