SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Nilsson Mattias 1977 ) ;pers:(Johansson Håkan 1977)"

Sökning: WFRF:(Nilsson Mattias 1977 ) > Johansson Håkan 1977

  • Resultat 1-7 av 7
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  •  
2.
  •  
3.
  • Johansson, Håkan T., 1977-, et al. (författare)
  • The unbound isotopes He-9,He-10
  • 2010
  • Ingår i: Nuclear Physics A. - 0375-9474. ; 842, s. 15-32
  • Tidskriftsartikel (refereegranskat)abstract
    • The unbound nuclei He-9 and He-10 have been produced in proton-knockout reactions from a 280 MeV/u Li-11 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, He-8 + n and He-8 + 2n, employing reaction models incorporating the structure of Li-11. The (8H)e + 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 He-8 + n threshold. It is argued that the s-state might not be the He-9 ground state. For He-8 + 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 (Gamma = 1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Gamma = 1.91(41) MeV) together with an excited state at 3.99(26) MeV (Gamma = 1.64(89) MeV). The two possible interpretations are discussed. (C) 2010 Elsevier B.V. All rights reserved.
  •  
4.
  • Johansson, Håkan T., 1977-, et al. (författare)
  • Three-body correlations in the decay of He-10 and Li-13
  • 2010
  • Ingår i: Nuclear Physics A. - 0375-9474. ; 847:1-2, s. 66-88
  • Tidskriftsartikel (refereegranskat)abstract
    • The very exotic nuclear resonance systems, 10He and 13Li, are produced in proton-knockout reactions from relativistic beams of 11Li and 14Be. The experimentally determined energy and angular correlations between their decay products, <img src="http://ars.els-cdn.com/content/image/1-s2.0-S0375947410006044-si1.gif" data-inlimgeid="1-s2.0-S0375947410006044-si1.gif" data-loaded="true" /> and <img src="http://ars.els-cdn.com/content/image/1-s2.0-S0375947410006044-si2.gif" data-inlimgeid="1-s2.0-S0375947410006044-si2.gif" data-loaded="true" />, are analyzed using an expansion of decay amplitudes in a restricted set of hyperspherical harmonics. By considering only a small number of terms it is possible to extract the expansion coefficients directly from the experimental three-body correlations. This provides a model-independent way of getting information about the decay process, on the structure of the decaying nucleus and on the quantum characteristics of the binary subsystems.The results show that the <img src="http://ars.els-cdn.com/content/image/1-s2.0-S0375947410006044-si3.gif" data-inlimgeid="1-s2.0-S0375947410006044-si3.gif" data-loaded="true" /> relative-energy spectrum can be interpreted as consisting of two resonances, an Iπ=0+ ground state and an excited Iπ=2+ state. The <img src="http://ars.els-cdn.com/content/image/1-s2.0-S0375947410006044-si6.gif" data-inlimgeid="1-s2.0-S0375947410006044-si6.gif" data-loaded="true" /> relative-energy spectrum is interpreted as an Iπ=3/2− ground state overlapping with excited states having a structure similar to the 2+ state in 10He but spread over several states due to the coupling to the Iπ=3/2− core. The13Li data also give evidence for a contribution of a configuration where the two neutrons occupy the d-shell.
  •  
5.
  • Marganiec, C., et al. (författare)
  • Coulomb breakup of 17Ne from the viewpoint of nuclear astrophysics
  • 2013
  • Ingår i: Proceedings of Science.
  • Konferensbidrag (refereegranskat)abstract
    • By the Coulomb breakup of 17Ne, the time-reversed reaction 15O(2p,γ)17Ne has been studied. This reaction might play an important role in the rp process, as a break-out reaction of the hot CNO cycle. The secondary 17Ne ion beam with an energy of 500 MeV/nucleon has been dissociated in a Pb target. The reaction products have been detected with the LAND-R3B experimental setup at GSI. The preliminary differential and integral Coulomb dissociation cross section sCoul has been determined, which then will be converted into a photo-absorption cross section sphot o, and a two-proton radiative capture cross section σcap. Additionally, information about the structure of the 17Ne, a potential two-proton halo nucleus, will be received. The analysis is in progress.
6.
  • Marganiec, J., et al. (författare)
  • STUDY OF THE O-15(2p,gamma)Ne-17 CROSS SECTION BY COULOMB DISSOCIATION OF Ne-17 FOR THE rp PROCESS OF NUCLEOSYNTHESIS
  • 2014
  • Ingår i: Acta Physica Polonica B. - 0587-4254. ; 45:2, s. 229-234
  • Konferensbidrag (refereegranskat)abstract
    • The O-15(2p, gamma)Ne-17 cross section has been studied by the inverse reaction, the Coulomb dissociation of Ne-17. The experiment has been performed at the GSI. The Ne-17 excitation energy prior to decay has been reconstructed by using the invariant-mass method. The preliminary differential and integral Coulomb dissociation cross sections (sigma(Coul)) have been extracted, which provide a photoabsorption (sigma(photo)) and a radiative capture cross section (sigma(cap)). Additionally, important information about the Ne-17 nuclear structure will be obtained. The analysis is in progress.
  •  
7.
  • Wamers, F., et al. (författare)
  • First Observation of the Unbound Nucleus Ne-15
  • 2014
  • Ingår i: Physical Review Letters. - 0031-9007. ; 112:13
  • Tidskriftsartikel (refereegranskat)abstract
    • We report on the first observation of the unbound proton-rich nucleus 15Ne. Its ground state and first excited state were populated in two-neutron knockout reactions from a beam of 500 MeV/u 17Ne. The 15Ne ground state is found to be unbound by 2.522(66) MeV. The decay proceeds directly to 13O with simultaneous two-proton emission. No evidence for sequential decay via the energetically allowed 2− and 1− states in 14F is observed. The 15Ne ground state is shown to have a strong configuration with two protons in the (sd) shell around 13O with a 63(5)% (1s1/2)2 component.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-7 av 7
 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy