Summary
The pion-momentum spectrum from K−-absorption stars in helium is calculated in the impulse approximation. The kaon is assumed to be pseudoscalar and to be captured from the 1s state. A final state consisting of free particles is used. The effect of final bound states is considered and taken into account phenomenologically. All final-state interactions are neglected. It is shown that the shape of the momentum spectrum is determined mainly by kinematics,i.e., the shapes and position of the spectral peaks are quite insensitive to detailed dynamical assumptions such as the nature of the K parity and capture orbit. The effect of final-state interactions is discussed.
Riassunto
Si calcola lo spettro della quantità di moto dei pioni da stelle di assorbimento K− in elio con l’approssimazione dell’impulso. Si suppone che il kaone sia pseudoscalare e che venga catturato dallo stato 1s. Si usa uno stato finale costituito da particelle libere. Si studia l’effetto degli stati legati finali e se ne tien conto fenomenologicamente. Si trascurano tutte le interazioni dello stato finale. Si dimostra che la forma dello spettro del momento è determinato principalmente dalla cinematica, cioè, le forme e le posizioni dei picchi spettrali non risentono per nulla da dettagliate supposizioni dinamiche quali la natura della parità del K e dell’orbita di cattura. Si discute l’effetto delle interazioni degli stati finali.
Similar content being viewed by others
References
J. Leitner, E. M. Harth, M. M. Block B. Brucker, I. Hughes, T. Kikuchi, C. Meltzer, A. Pevsner, F. Anderson, H. Cohn:Bull. Am. Phys. Soc. (New York Meeting, 1959).
W. Alvarez, H. Bradner, A. H. Rosenfeld, F. T. Solmitz andR. D. Teipp:Nuovo Cimento,5, 1026 (1956).
This process has been discussed byHorwitz, Miller, Murray, Taft andSchwartz in connection with K−-d absorption:Bull. Am. Phys. Soc.,3, 363 (1958).
A. Fuji andR. Marshak: NYO Report 2166, Univ. of Rochester (March 1957).
A. Pevsner, F. Anderson, M. M. Block B. Brucker I. Hughes, T. Kikuchi, C. Meltzer, H. Cohn, E. Harth andJ. Ceither:Bull. Am. Phys. Soc. (New York Meeting, 1959).
R. Dalitz:Phys. Rev.,111, 967 (1958).
R. Hofstadter:Rev. Mod. Phys.,28, 214 (1956).
A. Pais andS. Treiman:Phys. Rev.,107, 1396 (1957).
Fuji andMarshak (4), using perturbation theory and global symmetry, have calculated analogous constants for K−-d absorption. The results do not agree with experiment.
B. Karplus andL. Rodberg:Inelastic final state interactions K− absorption in deuterium (submitted toPhys. Rev., 1959).
Author information
Authors and Affiliations
Additional information
This work was done under the auspices of the U.S. Atomic Energy Commission and the Office of Scientific Research.
Rights and permissions
About this article
Cite this article
Lfitner, J., Lichtman, S. Pion-momentum spectrum from K− absorption in helium. Nuovo Cim 15, 719–728 (1960). https://doi.org/10.1007/BF02732688
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02732688