Evidence for the dipole nature of the low-energy γ enhancement in Fe56

Larsen, A. C.; Blasi, N.; Bracco, A.; Camera, F.; Eriksen, T. K.; Gorgen, A.; Guttormsen, M.; Hagen, T. W.; Leoni, S.; Million, B.; Nyhus, H. T.; Renstrom, T.; Rose, S. J.; Ruud, I. E.; Siem, S.; Tornyi, T.; Tveten, G. M.; Voinov, A. V.; Wiedeking, M.

doi:10.1103/PhysRevLett.111.242504

Title: Evidence for the dipole nature of the low-energy $γ$ enhancement in ${}^{56}{Fe}$

Journal Article · Wed Dec 11 00:00:00 EST 2013 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.111.242504· OSTI ID:1256982

Larsen, A. C. ^[1]; Blasi, N. ^[2]; Bracco, A. ^[3]; Camera, F. ^[3]; Eriksen, T. K. ^[1]; Gorgen, A. ^[1]; Guttormsen, M. ^[1]; Hagen, T. W. ^[1]; Leoni, S. ^[3]; Million, B. ^[2]; Nyhus, H. T. ^[1]; Renstrom, T. ^[1]; Rose, S. J. ^[1]; Ruud, I. E. ^[1]; Siem, S. ^[1]; Tornyi, T. ^[4]; Tveten, G. M. ^[1]; Voinov, A. V. ^[5]; Wiedeking, M. ^[6]

Univ. of Oslo, Oslo (Norway)
INFN, Milano (Italy)
INFN, Milano (Italy); Univ. of Milano, Milano (Italy)
Univ. of Oslo, Oslo (Norway); MTA ATOMKI, Debrecen (Hungary)
Ohio Univ. Athens, OH (United States)
iThemba LABS, Somerset West (South Africa)

Here, the γ-ray strength function of ⁵⁶Fe has been measured from proton-γ coincidences for excitation energies up to ≈11 MeV. The low-energy enhancement in the γ-ray strength function, which was first discovered in the (³He,αγ)⁵⁶Fe reaction, is confirmed with the (p,p'γ)⁵⁶Fe experiment reported here. Angular distributions of the γ rays give for the first time evidence that the enhancement is dominated by dipole transitions.

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Research Organization:: Ohio Univ., Athens, OH (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: NA0001837; FG02-88ER40387

OSTI ID:: 1256982

Journal Information:: Physical Review Letters, Vol. 111, Issue 24; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 59 works

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