| 1. |
- Bergmann, U. C., et al.
(författare)
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Analysis of decay data from neutron-rich nuclei
- 2001
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Ingår i: European Physical Journal A. - 1434-601X .- 1434-6001. ; 11:3, s. 279-284
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Tidskriftsartikel (refereegranskat)abstract
- The beta -decays of the neutron-rich nuclei Be-12 and Ne-29 have been studied. The statistical correlations between the almost identical half-lives of Be-12 and its daughter B-12 are analysed for a large sample of Be-12 decay data. Stringent mutual bounds are obtained on the parameter set, leading to a precise determination of the Be-12 half-life of 21.50 +/- 0.04 ms. From a simultaneous detection of beta -particles and neutrons from the decay of Ne-29 the neutron emission probability, P-n, is determined to 17 +/- 5%. No indication of two-neutron emission is seen from this nucleus. An upper limit of 2.2% (90% confidence level) is established for P-2n.
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| 2. |
- Bergmann, U. C., et al.
(författare)
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On the beta-decay of C-9
- 2001
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Ingår i: Nuclear Physics A. - 0375-9474. ; 692:3-4, s. 427-450
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Tidskriftsartikel (refereegranskat)abstract
- In beta -decay experiments on C-9 at CERN/ISOLDE the beta -strength was determined to the ground state, the 12.2 MeV excited state and the Isobaric Analog State (IAS) at 14.655 MeV in B-9. A large beta -strength asymmetry is deduced for the mirror transitions of C-9 and Li-9 to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from a narrow energy region around the 12.2 MeV resonance is obtained within a sequential model involving the ground and first-excited states of Li-5 and Be-8. From the study of angular correlations the spin of the 12.2 MeV state is determined as 5/2(-). For the first time the population of the IAS is observed in beta -decay and new information on the decay of this state is obtained. The advantages of a closely packed. highly segmented detector setup are demonstrated. (C) 2001 Elsevier Science B.V. All rights reserved.
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| 3. |
- Borge, M. J. G., et al.
(författare)
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Asymmetry in the super-allowed beta-transitions of the A=9 isobars
- 2004
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 738:1-4 SUPPL., s. 206-210
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Tidskriftsartikel (refereegranskat)abstract
- We report here on the recent beta-decay studies of the A = 9 isobar made at ISOLDE/CERN. Mirror beta transitions in the A=9 chain are compared and a large asymmetry factor is deduced for the transitions to high excitation energy in Be-9 (11.8 MeV) and B-9 (12.2 MeV) fed in the beta-decay of Li-9 and C-9 respectively. It is shown that the asymmetry is not due to experimental problems or differences in the mechanisms of breakup or in the spin of the states. Only differences in the partial decay branches of the breakup channels have been found. As no asymmetry is found in the gs to gs transition it must be due to the particular structure of these excited states.
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| 4. |
- Borge, M. J. G., et al.
(författare)
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Proton dripline studies at ISOLDE: Ar-31 and C-9
- 2002
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Ingår i: Nuclear Physics A. - 0375-9474. ; 701, s. 373C-377C
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Konferensbidrag (refereegranskat)abstract
- In this contribution examples of the application of new technologies to disentangle the mechanism of beta-delayed multiparticle emission are given. In particular the mechanism of beta-delayed two-proton emission from Ar-31 has been resolved and proved to be sequential, a preview of C-9-decay data is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
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| 5. |
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| 6. |
- Cederkäll, Joakim, et al.
(författare)
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REX-ISOLDE - experiences from the first year of operation
- 2004
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 746, s. 17-17
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Konferensbidrag (refereegranskat)abstract
- The Radioactive beam EXperiment (REX) at CERN-ISOLDE has been commissioned and the first experiments successfully completed during 2002 and 2003. The concept used for post-acceleration has proven to be flexible and the experimental program has therefore been extended during the past year. This paper relays some experiences drawn from using the machine in the current program and also conveys some plans for the future.
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| 7. |
- Enerbäck, Charlotta, 1965, et al.
(författare)
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Stronger association with HLA-Cw6 than with corneodesmosin (S-gene) polymorphisms in Swedish psoriasis patients.
- 2000
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Ingår i: Archives of dermatological research. - : Springer Science and Business Media LLC. - 0340-3696 .- 1432-069X. ; 292:11, s. 525-30
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Tidskriftsartikel (refereegranskat)abstract
- Psoriasis vulgaris is strongly associated with certain human leukocyte antigens, especially in early onset. The purpose of this study was to study the HLA-Cw6 allele and its contribution to disease susceptibility in a set of 104 families with at least two affected siblings. A sequencing method was utilized to examine the two exons that build up the antigen binding site of the C locus receptor. DNA from patients homozygous for Cw6 based on haplotype information were sequenced. The results confirmed the identity of the Cw6 allele in affected individuals with the consensus sequence for Cw*0602. We screened the set of families for psoriasis patients homozygous for Cw6 and found 11 individuals with a mean age at onset of 16.1 years. The corresponding figure for the Cw6 heterozygotes was 18.45 years and for the Cw6-negatives 22.36 years. This is indicative of a gene dose effect. We performed a transmission disequilibrium test (TDT) on the Cw6 allele per se, used as a biallelic marker. The analysis resulted in a P-value of 5.3 x 10(-17) (t167/nt45). This greatly exceeds our previous results of a TDT in the region, including microsatellite markers and single nucleotide polymorphisms (SNPs) in the coding part of the S gene (corneodesmosin), which is a suggested candidate gene in the region. The maximum nonparametric linkage (NPL) value was also reached using HLA-C as a marker. We conclude that Cw6 is the allele which shows the highest degree of association with psoriasis in our set of families and we propose that it directly influences the age at onset of the disease rather than increasing the genetic load in accordance with a polygenic theory.
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| 8. |
- Fynbo, H. O. U., et al.
(författare)
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The beta 2p decay mechanism of Ar-31
- 2000
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Ingår i: Nuclear Physics A. - 0375-9474. ; 677, s. 38-60
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Tidskriftsartikel (refereegranskat)abstract
- We have measured the beta-decay of Ar-31 with a high granularity setup sensitive to multiparticle decay branches. Two-proton emission is observed from the isobaric analog state in Cl-31 to the four lowest states in P-29 and furthermore from a large number of states fed in Gamow-Teller transitions. The mechanism of two-proton emission is studied via energy and angular correlations between the two protons. In all cases the mechanism is found to be sequential yielding information about states in S-30 up to 8 MeV excitation energy. Improved data on the beta-delayed one-proton branches together with the two-proton data provide precise information about the beta-strength distribution up to 15 MeV excitation energy.
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| 9. |
- Habs, D., et al.
(författare)
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The REX-ISOLDE project
- 2000
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Ingår i: Hyperfine Interactions. - 0304-3843 .- 1572-9540. ; 129:1-4, s. 43-66
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Tidskriftsartikel (refereegranskat)abstract
- The Radioactive Beam Experiment REX-ISOLDE [1-3] is a pilot experiment at ISOLDE (CERN) testing the new concept of post acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In order to prepare the ions for the experiments singly charged radioactive ions from the on-line mass separator ISOLDE will be cooled and bunched in a Penning trap, charge bred in an electron beam ion source (EBIS) and finally accelerated in the LINAC. The LINAC consists of a radiofrequency quadrupole (RFQ) accelerator, which accelerates the ions up to 0.3 MeV/u, an interdigital H-type (IH) structure with a final energy between 1.1 and 1.2 MeV/u and three seven gap resonators, which allow the variation of the final energy. With an energy of the radioactive beams between 0.8 MeV/u and 2.2 MeV/u a wide range of experiments in the field of nuclear spectroscopy, astrophysics and solid state physics will be addressed by REX-ISOLDE.
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| 10. |
- Kester, O., et al.
(författare)
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Accelerated radioactive beams from REX-ISOLDE
- 2003
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 20-20
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Konferensbidrag (refereegranskat)abstract
- In 2001 the linear accelerator of the Radioactive beam EXperiment (REX-ISOLDE) delivered for the first time accelerated radioactive ion beams, at a beam energy of 2 MeV/u. REX-ISOLDE uses the method of charge-state breeding, in order to enhance the charge state of the ions before injection into the LINAC. Radioactive singly-charged ions from the on-line mass separator ISOLDE are first accumulated in a Penning trap, then charge bred to an A/q
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