The unbound isotopes 9,10He

H. T. Johansson; Yu Aksyutina; T. Aumann; K. Boretzky; M. J G Borge; A. Chatillon; L. V. Chulkov; D. Cortina-Gil; U. Datta Pramanik; H. Emling; C. Forssén; H. O U Fynbo; H. Geissel; G. Ickert; B. Jonson; R. Kulessa; C. Langer; M. Lantz; T. LeBleis; K. Mahata; M. Meister; G. Münzenberg; T. Nilsson; G. Nyman; R. Palit; S. Paschalis; W. Prokopowicz; R. Reifarth; A. Richter; K. Riisager; G. Schrieder; H. Simon; K. Sümmerer; O. Tengblad; H. Weick; M. V. Zhukov

doi:10.1016/j.nuclphysa.2010.04.006

The unbound isotopes ^9,10He

H. T. Johansson, Yu Aksyutina, T. Aumann, K. Boretzky, M. J G Borge, A. Chatillon, L. V. Chulkov, D. Cortina-Gil, U. Datta Pramanik, H. Emling, C. Forssén, H. O U Fynbo, H. Geissel, G. Ickert, B. Jonson^*, R. Kulessa, C. Langer, M. Lantz, T. LeBleis, K. MahataM. Meister, G. Münzenberg, T. Nilsson, G. Nyman, R. Palit, S. Paschalis, W. Prokopowicz, R. Reifarth, A. Richter, K. Riisager, G. Schrieder, H. Simon, K. Sümmerer, O. Tengblad, H. Weick, M. V. Zhukov

^*Corresponding author for this work

Physics

Research output: Contribution to journal › Article › peer-review

Abstract

The unbound nuclei ⁹He and ¹⁰He have been produced in proton-knockout reactions from a 280 MeV/u ¹¹Li beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He8+n and He8+2n, employing reaction models incorporating the structure of ¹¹Li.The He8+n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He8+n threshold. It is argued that the s-state might not be the ⁹He ground state.For He8+n+n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Γ=1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Γ=1.91(41) MeV) together with an excited state at 3.99(26) MeV (Γ=1.64(89) MeV). The two possible interpretations are discussed.

Original language	English
Pages (from-to)	15-32
Number of pages	18
Journal	Nuclear Physics A
Volume	842
Issue number	1-4
DOIs	https://doi.org/10.1016/j.nuclphysa.2010.04.006
Publication status	Published - Oct 2010

Keywords

Deduced resonance state parameters
Measured
Nuclear reactions

Access to Document

10.1016/j.nuclphysa.2010.04.006

Cite this

Johansson, H. T., Aksyutina, Y., Aumann, T., Boretzky, K., Borge, M. J. G., Chatillon, A., Chulkov, L. V., Cortina-Gil, D., Datta Pramanik, U., Emling, H., Forssén, C., Fynbo, H. O. U., Geissel, H., Ickert, G., Jonson, B., Kulessa, R., Langer, C., Lantz, M., LeBleis, T., ... Zhukov, M. V. (2010). The unbound isotopes ^9,10He. Nuclear Physics A, 842(1-4), 15-32. https://doi.org/10.1016/j.nuclphysa.2010.04.006

@article{03aec64f174b4dd4917bc4dada23890e,

title = "The unbound isotopes 9,10He",

abstract = "The unbound nuclei 9He and 10He have been produced in proton-knockout reactions from a 280 MeV/u 11Li beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He8+n and He8+2n, employing reaction models incorporating the structure of 11Li.The He8+n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He8+n threshold. It is argued that the s-state might not be the 9He ground state.For He8+n+n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Γ=1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Γ=1.91(41) MeV) together with an excited state at 3.99(26) MeV (Γ=1.64(89) MeV). The two possible interpretations are discussed.",

keywords = "Deduced resonance state parameters, Measured, Nuclear reactions",

author = "Johansson, {H. T.} and Yu Aksyutina and T. Aumann and K. Boretzky and Borge, {M. J G} and A. Chatillon and Chulkov, {L. V.} and D. Cortina-Gil and {Datta Pramanik}, U. and H. Emling and C. Forss{\'e}n and Fynbo, {H. O U} and H. Geissel and G. Ickert and B. Jonson and R. Kulessa and C. Langer and M. Lantz and T. LeBleis and K. Mahata and M. Meister and G. M{\"u}nzenberg and T. Nilsson and G. Nyman and R. Palit and S. Paschalis and W. Prokopowicz and R. Reifarth and A. Richter and K. Riisager and G. Schrieder and H. Simon and K. S{\"u}mmerer and O. Tengblad and H. Weick and Zhukov, {M. V.}",

year = "2010",

month = oct,

doi = "10.1016/j.nuclphysa.2010.04.006",

language = "English",

volume = "842",

pages = "15--32",

journal = "Nuclear Physics A",

issn = "0375-9474",

publisher = "Elsevier",

number = "1-4",

}

Johansson, HT, Aksyutina, Y, Aumann, T, Boretzky, K, Borge, MJG, Chatillon, A, Chulkov, LV, Cortina-Gil, D, Datta Pramanik, U, Emling, H, Forssén, C, Fynbo, HOU, Geissel, H, Ickert, G, Jonson, B, Kulessa, R, Langer, C, Lantz, M, LeBleis, T, Mahata, K, Meister, M, Münzenberg, G, Nilsson, T, Nyman, G, Palit, R, Paschalis, S, Prokopowicz, W, Reifarth, R, Richter, A, Riisager, K, Schrieder, G, Simon, H, Sümmerer, K, Tengblad, O, Weick, H & Zhukov, MV 2010, 'The unbound isotopes ^9,10He', Nuclear Physics A, vol. 842, no. 1-4, pp. 15-32. https://doi.org/10.1016/j.nuclphysa.2010.04.006

TY - JOUR

T1 - The unbound isotopes 9,10He

AU - Johansson, H. T.

AU - Aksyutina, Yu

AU - Aumann, T.

AU - Boretzky, K.

AU - Borge, M. J G

AU - Chatillon, A.

AU - Chulkov, L. V.

AU - Cortina-Gil, D.

AU - Datta Pramanik, U.

AU - Emling, H.

AU - Forssén, C.

AU - Fynbo, H. O U

AU - Geissel, H.

AU - Ickert, G.

AU - Jonson, B.

AU - Kulessa, R.

AU - Langer, C.

AU - Lantz, M.

AU - LeBleis, T.

AU - Mahata, K.

AU - Meister, M.

AU - Münzenberg, G.

AU - Nilsson, T.

AU - Nyman, G.

AU - Palit, R.

AU - Paschalis, S.

AU - Prokopowicz, W.

AU - Reifarth, R.

AU - Richter, A.

AU - Riisager, K.

AU - Schrieder, G.

AU - Simon, H.

AU - Sümmerer, K.

AU - Tengblad, O.

AU - Weick, H.

AU - Zhukov, M. V.

PY - 2010/10

Y1 - 2010/10

N2 - The unbound nuclei 9He and 10He have been produced in proton-knockout reactions from a 280 MeV/u 11Li beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He8+n and He8+2n, employing reaction models incorporating the structure of 11Li.The He8+n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He8+n threshold. It is argued that the s-state might not be the 9He ground state.For He8+n+n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Γ=1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Γ=1.91(41) MeV) together with an excited state at 3.99(26) MeV (Γ=1.64(89) MeV). The two possible interpretations are discussed.

AB - The unbound nuclei 9He and 10He have been produced in proton-knockout reactions from a 280 MeV/u 11Li beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He8+n and He8+2n, employing reaction models incorporating the structure of 11Li.The He8+n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He8+n threshold. It is argued that the s-state might not be the 9He ground state.For He8+n+n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Γ=1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Γ=1.91(41) MeV) together with an excited state at 3.99(26) MeV (Γ=1.64(89) MeV). The two possible interpretations are discussed.

KW - Deduced resonance state parameters

KW - Measured

KW - Nuclear reactions

UR - http://www.scopus.com/inward/record.url?scp=77953538537&partnerID=8YFLogxK

U2 - 10.1016/j.nuclphysa.2010.04.006

DO - 10.1016/j.nuclphysa.2010.04.006

M3 - Article

AN - SCOPUS:77953538537

SN - 0375-9474

VL - 842

SP - 15

EP - 32

JO - Nuclear Physics A

JF - Nuclear Physics A

IS - 1-4