| 1. |
- Axelsson, H., et al.
(författare)
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Candidates for Electron-Neutrino Mass Measurements - the Case of Kr-81
- 1988
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 210:1-2, s. 249-252
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Tidskriftsartikel (refereegranskat)abstract
- The nuclear data of the known candidates for neutrino mass determination by resonant electron-capture beta decay are reviewed. New results are presented for the isotope 81Kr, where the transition to the 276 keV state has been found to have QEC=4.7±0.5 keV and a branching ratio of (3.0±0.2)×10−3
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| 2. |
- Bjornstad, T., et al.
(författare)
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Study of the Giant Gamow-Teller Resonance in Nuclear Beta-Decay - the Case of Ar-32
- 1985
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 443:2, s. 283-301
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Tidskriftsartikel (refereegranskat)abstract
- Delayed proton and gamma emissions following the β-decay of 32Ar have been studied. The half-life of 32Ar is 98 ± 2 ms, and the T = 2 analogue state in 32Cl lies at the excitation energy 5036 ± 12 keV. From the intensity of the feeding to this state the proton intensities can be converted to an absolute scale leading to a total proton branching ratio of (43 ± 3)%. From proton-gamma coincidence measurements it emerges that (1.9 ± 0.2)% of the protons lead to the first-excited state in 31S. A level scheme up to 8.75 MeV excitation in 32Cl has been constructed and the Gamow-Teller strength function has been deduced. The result is a renormalization of the axial-vector strength to (49 ± 5)% of the free-nucleon value.
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| 3. |
- Borge, M. J. G., et al.
(författare)
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Beta-Delayed Proton and Alpha Emission in the Decay of Ne-17
- 1988
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 490:2, s. 287-306
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Tidskriftsartikel (refereegranskat)abstract
- The beta-delayed proton and alpha spectra from 17Ne have been studied with Si-detectors. The Gamow-Teller strength in the decay of 17Ne has been extracted and compared with a two-particle-one-hole shell-model calculation. The experimental strength is quenched by a factor of 0.82 with respect to the calculated one. Furthermore, the decay scheme has been improved and is discussed in some detail. The proton emitting levels in 17F are very broad and the line shapes are strongly influenced by phase-space effects. Interference between peaks corresponding to the same intermediate spin is a prominent feature emerging clearly with the good resolution and statistics of the present work.
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| 4. |
- Borge, M. J. G., et al.
(författare)
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Limits on Neutrino-Mixing from the Internal Bremsstrahlung Spectrum of I-125
- 1986
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Ingår i: Physica Scripta. - 1402-4896 .- 0031-8949. ; 34:6A, s. 591-596
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Tidskriftsartikel (refereegranskat)abstract
- The massive antineutrino recently reported by Simpson in an experiment on tritium decay has not been confirmed by experiments on 35S decay. As an independent check, we report here the negative result of a search for the corresponding antiparticle (a massive neutrino) using the decay of 125I. As a by-product, we give accurate data on internal-bremsstrahlung spectra which we have followed over close to four decades in intensity, and we report a new way of measuring its E1/M1 ratio. The experiment provides a new and very accurate value for the 125I-125Te mass difference of 186.1 ± 0.3 keV.
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| 5. |
- Borge, M. J. G., et al.
(författare)
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Study of the Giant Gamow-Teller Resonance in Nuclear Beta-Decay - the Case of Ar-33
- 1987
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Ingår i: Physica Scripta. - : IOP Publishing. - 1402-4896 .- 0031-8949. ; 36:2, s. 218-223
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Tidskriftsartikel (refereegranskat)abstract
- Delayed proton and gamma emissions following the beta decay of 33Ar have been studied. From the calculated intensity of the feeding to the T = 3/2 analogue state in 33C1, the proton intensities have been put on an absolute scale leading to a proton branching ratio of 38.7 ± 1.0%. A proton branch to the first excited state in 32S at 2230.2 keV (1π = 2+) with an intensity of 0.77 ± 0.10% was obtained from gamma singles and proton-gamma coincidence data. The complete spectroscopic information on 33Ar allows the Gamow-Teller (GT) strength function from the gound state and up to 9.25 MeV excitation energy in 33C1 to be deduced. The total strength observed in this interval is 2.90 in absolute units.
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| 6. |
- Borge, M. J. G., et al.
(författare)
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The Axial-Vector Strength in the Proton-Rich Argon Isotopes
- 1989
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Ingår i: Zeitschrift fur Physik A Hadrons and Nuclei. - 1431-5831 .- 0939-7922. ; 332:4, s. 413-417
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Tidskriftsartikel (refereegranskat)abstract
- The proton-rich isotopes32Ar-35Ar represent the first sequence for which the superallowed Gamow-Teller strength is known out toZ− N=4. The results are compared with two sets of predictions from large shell-model calculations, which give systematically different quenching factors, on the average 0.54 and 0.89. Possible reasons for this are discussed. A comparison is also made with the Gamow-Teller strength of proton-rich isotopes of neighbouring elements.
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| 7. |
- Hansen, Erling K, et al.
(författare)
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Norwegian practice for concrete bridge deck protection
- 1988
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Ingår i: Proceedings of Roads and traffic safety on two continents in Gothenburg, Sweden, 9-11 September 1987. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 111-121
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 8. |
- Nyholm, R., et al.
(författare)
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Submicrometer-resolution photoelectron-spectroscopy at MAX Lab
- 1989
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 60:7, s. 2168-2171
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Tidskriftsartikel (refereegranskat)abstract
- The design of a photoemission microprobe beamline at the MAX laboratory is presented. The beamline will utilize the radiation from a 26 period undulator on the 550-MeV MAX storage ring. The beamline will be capable of providing about 1010 photons/s of monochromatized radiation (bandwidth better than 0.25 eV) in the energy range of 20 to 150 eV focused into a submicrometer focal spot. It will be used for scanning photoemission experiments with a lateral resolution better than 1 μm. The optical system is comprised of a plane-grating monochromator with a Kirkpatrick-Baez objective and a specially designed ellipsoidal focusing mirror.
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| 9. |
- Nyholm, R., et al.
(författare)
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SURFACE SCIENCE AT MAX-LAB
- 1989
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 282:2-3, s. 553-558
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Tidskriftsartikel (refereegranskat)
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| 10. |
- Riisager, K., et al.
(författare)
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The Internal Bremsstrahlung Spectra from the Ec Beta-Decay of Pt-193 and Ho-163
- 1985
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Ingår i: Physica Scripta. - : IOP Publishing. - 1402-4896 .- 0031-8949. ; 31:5, s. 321-327
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Tidskriftsartikel (refereegranskat)abstract
- Internal bremsstrahlung spectra following electron-capture (EC) beta decay have been calculated in two versions of an extended Glauber-Martin theory. The case of 193Pt which has a QEC-value that falls 20 keV below the 1s resonance point, is ideally suited for a test of this theory. The experimental data, both singles and L X-ray-bremsstrahlung coincidences, show that all the main features of the spectra are understood, although the absolute intensities agree to within a factor 1.5-2 only. The same calculations have been applied to 163Ho, with a QEC of 2.82 keV, one of the main cases for an accurate measurement of the electron neutrino mass. The predicted occurence of an interference minimum near the end-point, however, makes the m(ve) experiment less attractive than one might have hoped for.
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