| 1. |
- VO, DT, et al.
(författare)
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SUPERDEFORMATION IN AU-191
- 1993
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 71:3, s. 340-343
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Tidskriftsartikel (refereegranskat)abstract
- A superdeformed band has been observed for the first time in an Au isotope. The reaction used was B-11 + W-186, demonstrating that very light ions can be used to populate superdeformed (SD) bands at high angular momentum. The band is assigned to 191Au. The gamma-ray energies are at the quarter-point energies of the 192Hg SD band, indicating that it is ''identical'' to that of 192Hg.
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| 2. |
- Cederwall, Bo, et al.
(författare)
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NEW OBLATE BAND IN HG-196 WITH QUENCHED M1 STRENGTH
- 1993
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 47:6, s. R2443-R2446
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Tidskriftsartikel (refereegranskat)abstract
- High-spin states in the nucleUs Hg-196 were populated in the reaction (Os(Be,5n))-Os-192 at a beam energy of 65 MeV. A regular rotational-like DELTAI = 1 band has been observed up to an excitation energy of E* almost-equal-to 8.7 MeV and spin I almost-equal-to 30hBAR. This is the second observation of a band of this character in a mercury isotope. The experimental results are compared with mean field calculations and semiclassical estimates based on the Donau-Frauendorf formalism. The mercury bands show significantly lower B(M1)/B(E2) branching ratios as compared with similar bands in light lead nuclei. This difference may be more readily explained by a difference in single-particle structure rather than by large differences in deformation between the lead and mercury configurations.
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| 3. |
- FALLON, P, et al.
(författare)
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EVIDENCE FOR M1 TRANSITIONS BETWEEN SUPERDEFORMED STATES IN HG-193
- 1993
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 70:18, s. 2690-2693
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Tidskriftsartikel (refereegranskat)abstract
- Two-way decay has been observed between superdeformed bands in Hg193. it is proposed the decays have M 1 multipolarity and connect signature partner bands. Candidates for the two-way gamma decays connecting superdeformed bands are observed for the first time.
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| 4. |
- Ma, Y, et al.
(författare)
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Core excitons and vibronic coupling in diamond and graphite
- 1993
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Ingår i: Physical Review Letters. - 0031-9007. ; 71:22, s. 3725-3728
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Tidskriftsartikel (refereegranskat)abstract
- The C 1s exciton in diamond is studied by soft x-ray emission excited with high resolution monochromatic photons. A strong phonon sideband of 5 eV wide is observed in the exciton recombination spectrum. With the phonon contribution, the exciton binding energy is estimated to be 1.5 eV. The excited atom is suggested to undergo Jahn-Teller relaxation similar to that of the nitrogen impurities in diamond. A similar exciton is observed at the sigma*-band threshold in graphite. These results provide new insights to the understanding of the core exciton and the donor problem in diamond and other systems.
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| 5. |
- OLIVEIRA, JRB, et al.
(författare)
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HIGH-K BANDS IN THE YB-166 REGION
- 1994
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 50:3, s. 1360-1369
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Tidskriftsartikel (refereegranskat)abstract
- High-K bands have been observed in the Yb-166,Yb-167,Yb-168 isotopes following the Sn-124(Ca-48,xn gamma) reaction. The nu h(11/2) bend in Yb-167 has been extended to higher spins. The high-K bands in the even-even isotopes were observed for the first time and show very high B(M1)/B(E2) ratios. Configuration assignments for the new bands are proposed. The results are interpreted within the tilted cranking model.
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| 6. |
- Skytt, P, et al.
(författare)
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Angle-resolved soft-x-ray fluorescence and absorption study of graphite : Physical Review B (Condensed Matter)
- 1994
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 50:15
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Tidskriftsartikel (refereegranskat)abstract
- The x-ray fluorescence and absorption of highly oriented pyrolytic graphite have been measured using monochromatic synchrotron radiation. The spectra can be separated into contributions from pi- and sigma-band components by measuring at different angles of incidence and at different emission angles. The shape of the x-ray fluorescence spectra varies dramatically with excitation energy near the C K edge. This dependence on excitation energy can be interpreted within a resonant-inelastic-scattering formalism. The results are compared with previously published band-structure calculations and photoemission results, and demonstrate the potential for using x-ray fluorescence to obtain symmetry-resolved band information.
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| 7. |
- Wang, Y, et al.
(författare)
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Functional homology between N-myc and c-myc in murine plasmacytomagenesis : plasmacytoma development in N-myc transgenic mice
- 1992
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Ingår i: Oncogene. - 0950-9232. ; 7:6, s. 7-1241
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Tidskriftsartikel (refereegranskat)abstract
- Mouse plasmacytomas induced by pristane oil alone, or in combination with Abelson murine leukemia virus (A-MuLV), regularly carry one of three alternative chromosomal translocations that juxtapose c-myc to immunoglobulin heavy- or light-chain loci. E mu-c-myc transgenic mice develop translocation-free plasmacytomas after induction by pristane oil and/or A-MuLV [Sugiyama, H., Silva, S., Wang, Y., Weber, G., Babonits, M., Rosen, A., Wiener, F. & Klein, G. (1990). Int. J. Cancer, 46, 845-852]. In order to test whether another member of the myc family, N-myc, could play a similar role as c-myc, we treated E mu-N-myc transgenic mice with pristane and helper-free A-MuLV. Of 20 mice that received a single pristane injection followed by A-MuLV, 17 developed plasmacytomas with a mean latency period of 54 +/- 20 days. In a corresponding group that only received a single pristane injection, five out of six transgenic mice developed plasmacytomas with a mean latency period of 142 +/- 32 days. However, after three monthly injections of pristane, all 15 transgenic mice developed plasmacytomas with a mean latency period of 128 +/- 20 days. All plasmacytomas expressed the N-myc transgene, while none of them expressed either c-myc or endogenous N-myc. None of the tumors carried the usual plasmacytoma-associated translocations.
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