| 1. |
|
|
| 2. |
- Borge, M. J. G., et al.
(författare)
-
Asymmetry in the super-allowed beta-transitions of the A=9 isobars
- 2004
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 738:1-4 SUPPL., s. 206-210
-
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.
|
|
| 3. |
- Borge, M. J. G., et al.
(författare)
-
Beta-delayed multiparticle emission studies at ISOL-type facilities
- 2004
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 746, s. 243-243
-
Konferensbidrag (refereegranskat)abstract
- We report here on the recent beta-decay studies made at ISOL-type Facilities to determine the multiparticle breakup mechanism of excited states in light nuclei by studying them in full kinematics. In particular the results obtained for the A = 9 isobars and the breakup of the 12.7 MeV state in C-12 of unnatural parity are discussed. The breakup of the latter has been debated since more than a decade. 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. As no asymmetry is found in the gs to gs transition it must be due to the particular structure of these excited states. The controversy on the breakup mechanism of the 12.7 MeV state is resolved.
|
|
| 4. |
- Pedersen, T.R., et al.
(författare)
-
Follow-up study of patients randomized in The Scandinavian Simvastatin Survival Study (4S) of cholesterol lowering
- 2000
-
Ingår i: American Journal of Cardiology. - 0002-9149 .- 1879-1913. ; 86:3, s. 257-262
-
Tidskriftsartikel (refereegranskat)abstract
- The Scandinavian Simvastatin Survival Study (4S) and other randomized clinical trials have demonstrated that cholesterol-lowering treatment with statins improves prognosis in patients with coronary atherosclerosis compared with placebo. The effect of therapy with statins beyond the typical 5 to 6 years' duration of the trials, in particular regarding the risk of cancer, has not been investigated. This study examines the long-term effects of simvastatin for up to 8 years on cause-specific mortality in patients with coronary heart disease (CHD). We performed an observational, government registry-based study of mortality in the groups originally randomized to simvastatin or placebo in the 4S over an additional 2-year follow-up period, so that the median total follow-up period was 7.4 years (range 6.9 to 8.3 in surviving patients). Randomization took place at outpatient clinics at 94 clinical centers in Denmark, Finland, Iceland, Norway, and Sweden from 1988 to 1989. Of 4,444 patients with CHD, 2,223 and 2,221 were randomized to treatment with placebo or simvastatin therapy, respectively. Patients received treatment with simvastatin, starting at 20 mg/day, with titration to 40 mg/day at 12 or 24 weeks if total cholesterol was >5.2 mmol/L (200 mg/dl), or placebo. After the double-blind period, most patients in both treatment groups received simvastatin as open-label prescription. Of the 1,967 patients originally treated with placebo and surviving the double-blind period, 97 (4.9%) died during the following 2 years. In the group randomized to simvastatin the corresponding number was 74 of the 2,039 survivors (3.6%). Adding these deaths to those occurring during the original trial, the total was 353 (15.9%) and 256 (11.5%) deaths in the groups originally randomized to placebo and simvastatin, respectively. The relative risk was 0.70 (95% confidence interval 0.60 to 0.82, p = 0.00002). The total number of cancer deaths was 68 (3.1%) in the placebo group and 52 (2.3%) in the simvastatin group (relative risk 0.73, 95% confidence interval 0.51 to 0.05, p = 0.087), and the numbers of noncardiovascular and other deaths were similar in both groups. We therefore conclude that treatment with simvastatin for up to 8 years in patients with CHD is safe and yields continued survival benefit. Copyright (C) 2000 Excerpta Medica Inc.
|
|
| 5. |
- Prezado, Y., et al.
(författare)
-
Large asymmetry in the strongest beta-transition for A=9
- 2003
-
Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 576:1-2, s. 55-61
-
Tidskriftsartikel (refereegranskat)abstract
- A new measurement of the beta-decay of Li-9 has clarified the feeding to the highest accessible states in Be-9. It is found that the P-decay mainly populates the 11.8 MeV state, whose spin is determined as 5/2(-). The extracted B-GT value of 5.3(0.9) is a factor 4.4(1.0) larger than that of the mirror transition from C-9. A theoretical explanation of such a pronounced beta-decay asymmetry is presently lacking. (C) 2003 Elsevier B.V. All rights reserved.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Bergmann, U. C., et al.
(författare)
-
Analysis of decay data from neutron-rich nuclei
- 2001
-
Ingår i: European Physical Journal A. - 1434-601X .- 1434-6001. ; 11:3, s. 279-284
-
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.
|
|
