Summary
A class of relativistic models, defined in terms of theN/D equations for asymptotically varying left-hand discontinuities and constant inelasticity, is considered. This is shown to present an alternative, analogous in certain respects to, but simpler than, the class of models based on the ladder approximation of the Bethe-Salpeter equation. In terms of anN/D amplitude with an asymptotically vanishing left-hand discontinuity an approximate strong-coupling calculation of the Pomeranchuk trajectory in agreement with the Regge pole analysis of the diffraction scattering experimental data is given; the corresponding residue function is also determined. AnN/D amplitude with an asymptotically constant left-hand discontinuity is shown to be associated with a nonshrinking diffraction peak. Certain analogies to the solutions for nonrelativistic scattering by regular or singular energy-independent potentials are also discussed.
Riassunto
Si studia una classe di modelli relativistici, definiti in funzione delle equazioniN/D per discontinuità a sinistra varianti asintoticamente e anelasticità costante. Si dimostra che essa presenta un'alternativa, per certi riguardi analoga, ma più semplice della classe di modelli basata sull'approssimazione a gradini dell'equazione di Bethe-Salpeter. Si espone un calcolo esplicito dell'accoppiamento forte della traiettoria di Pomeranchuk in funzione di un'ampiezzaN/D con una discontinuità a sinistra che tende asintoticamente a zero, in accordo con l'analisi in poli di Regge dei dati sperimentali dello scattering di diffrazione; si determina anche la corrispondente funzione residua. Si dimostra che un'ampiezzaN/D con una discontinuità a sinistra asintoticamente costante è associata ad un picco di diffrazione che non si restringe. Si discutono anche alcune analogie con le soluzioni per lo scattering non relativistico con potenziali regolari o singolari indipendenti dall'energia.
Similar content being viewed by others
References
G. C. Wick:Phys. Rev.,96, 1124 (1954);A. Bastai, L. Bertocchi, S. Fubini G. Furlan andM. Tonin:Nuovo Cimento,30, 1512 (1963).
B. W. Lee andR. F. Sawyer:Phys. Rev.,127, 2266 (1962).
R. F. Sawyer:Phys. Rev.,131, 1384 (1963);P. Suranyi:Phys. Lett.,6, 59 (1963);G. Cosenza, L. Sertorio andM. Toller:Nuovo Cimento,31, 1086 (1964);M. Baker andI. J. Muzinich:Phys. Rev.,132, 2291 (1963);A. P. Swift andB. W. Lee:Journ. Math. Phys.,5, 908 (1964).
R. F. Sawyer:Phys. Rev.,134, B 448 (1964);G. Domokos, P. Suranyi andA. Vančura: CERN Preprint 9011/TH. 432.
W. Güttinger, R. Penzl andE. Pfaffelhuber:Ann. of Phys.,33, 246 (1965);B. A. Arbuzov andA. T. Filippov:Nuovo Cimento,38, 796 (1965).
A. P. Contogouris:Nuovo Cimento,37, 1712 (1965).
The analyticity inl of theN/D amplitude of certain relativistic scalar-meson theories by means of perturbative expansions in the coupling constant has been studied byK. Bardakci andD. Geffen:Phys. Rev.,132, 1361 (1963).
J. C. Polkinghorne:Journ. Math. Phys.,4, 503 (1963);P. G. Federbush andM. T. Grisaru:Ann. of Phys.,22, 263 (1963).
N. Nakanishi:Phys. Rev.,135, B 1430 (1964);G. Tiktopoulos andS. B. Treiman:Phys. Rev.,137, B 1597 (1965);M. Restignoli, L. Sertorio andM. Toller:Nuovo Cimento,37, 511 (1965).
D. Atkinson andA. P. Contogouris:Nuovo Cimento,39, 1082 (1965).
A. P. Contogouris andD. Atkinson:Nuovo Cimento,39, 1102 (1965).
This case has been studied by:M. B. Halpern:Nuovo Cimento andPhys. Rev. (to be published).
A. Erdelyi (Ed.):Higher Transcendental Functions (New York, 1953), vol.1.
V. N. Gribov:Žurn. Ėksp. Teor. Fiz.,42, 1260 (1962) (translationSov. Phys. JETP,15, 873 (1962);A. Barut andD. Zwanziger:Phys. Rev.,127, 974 (1962);K. Bardakci:Phys. Rev.,127, 1832 (1962).
C. Lovelace:Scottish Universities, Summer School Lecture Notes (Edinburgh, 1964);G. Tiktopoulos:Phys. Rev.,133, B 1231 (1964), Appendix.
R. Courant andD. Hilbert:Methods of Mathematical Physics, vol.1, Chap. III (New York, 1953).
S. J. Lindenbaum:Proceedings of the 12th Annual International Conference on High Energy Physivs, Dubna, 1964 (to be published).
The fact that ourN/D amplitude corresponds to scattering of scalar particles does not really matter. For, if the existence of a Regge trajectory with the vacuum quantum numbers passing froml=1 ats=0 is a useful concept, this trajectory will be the same for all elastically scattered hadrons.
R. J. N. Phillips andW. Rarita:Phys. Rev.,139, B 1336 (1965).
D. Amati, A. Stanghellini andS. Fubini:Nuovo Cimento,26, 896 (1962);L. Bertocchi, S. Fubini andM. Tonin:Nuovo Cimento,25, 626 (1962).
L. Van Hove:Nuovo Cimento,28, 798 (1963);Rev. Mod. Phys.,36, 655 (1964).
In this connection, the identification ofm with the mass of the pion may be justified by the fact that most of the secondaries produced in high-energy inelastic collisions are pions.
A. Erdelyi (Ed.):Tables of Integral Transforms, vol.1 (New York, 1954).
For a fixed physicall>1 the branch point of (4.17) is developed when the potentialg/r 2 exceeds the centrifugal term (~l(l+1)/r 2≈(l+1/2)3/r 2). Compare this to the correspondingN/D situation where the branch points in theg-plane are developed when the asymptotic limit of the constant left-hand discontinuity exceeds the unitarity bounds of the right-hand discontinuity: 0<Im A t (v)<1(ref.(10)).D. Atkinson andA. P. Contogouris:Nuovo Cimento,39, 1082 (1965). 0
M. Froissart:Phys. Rev.,123, 1053 (1961);A. Martin:Phys. Rev.,129, 1432 (1963).
E. Predazzi andT. Regge:Nuovo Cimento,24, 518 (1962). An interesting iterative approach for the amplitude of scattering by singular potentials has been recently proposed byF. Calogero (Università di Roma preprint).
For a criticism of the nonrenormalizable Bethe-Salpeter solutions (obtained after a Wick rotation) from the axiomatic field-theory point of view seeK. Bardakci andB. Schroer. Institute for Advanced Study preprint. As it has been repeatedly stressed, the analogies discussed in our work refer only to analyticity ing andl.
Author information
Authors and Affiliations
Additional information
Traduzione a cura della Redazione.
Rights and permissions
About this article
Cite this article
Contogouris, A.P. Analytic and asymptotic properties of solubleN/D models. Nuovo Cimento A (1965-1970) 44, 927–945 (1966). https://doi.org/10.1007/BF02719340
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02719340