Longitudinal asymmetry in a neutron radiative capture reaction of 139La

doi:10.1016/0375-9474(89)90345-X

Nuclear Physics A

Volume 504, Issue 2, 13 November 1989, Pages 269-276

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Abstract

An asymmetry in the cross section for the neutron-induced reaction of ¹³⁹La was examined by a simultaneous measurement of the capture γ-ray and the neutron transmission. Sizable asymmetry was observed only in the p-wave resonance at E_n = 0.734 eV. No significant asymmetry was observed in the other reactions. The asymmetry in the p-wave resonance was roughly constant as a function of E_n. The average asymmetries in the resonance were A_1,γ = (9.5±0.3)% and A_L,n = (9.7±0.5)% in the γ-ray and the transmission measurements, respectively.

References (16)

V.P. Alfimenkov
Nucl. Phys.
(1983)
L. Stodolsky
Nucl. Phys.
(1982)
V.E. Bunakov et al.
Nucl. Phys.
(1983)
S. Satoh, KEK internal...
Y. Masuda
Hyperfine Interactions
(1987)
Y. Masuda
Nucl. Phys.
(1988)
V.E. Bunakov et al.
Z. Phys.
(1982)
P.K. Kabir
Phys. Rev.
(1982)

There are more references available in the full text version of this article.

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Longitudinal asymmetry in a neutron radiative capture reaction of 139La

Abstract

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Hyperfine Interactions

Nucl. Phys.

Z. Phys.

Phys. Rev.

Longitudinal asymmetry in a neutron radiative capture reaction of ¹³⁹La