1. |
- Borge, M. J. G., et al.
(författare)
-
Proton dripline studies at ISOLDE: Ar-31 and C-9
- 2002
-
Ingår i: Nuclear Physics A. - 0375-9474. ; 701, s. 373C-377C
-
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.
|
|
2. |
- Kester, O., et al.
(författare)
-
Accelerated radioactive beams from REX-ISOLDE
- 2003
-
Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 20-20
-
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
|
|
3. |
- Markenroth, Karin, 1973, et al.
(författare)
-
Crossing the dripline to N-11 using elastic resonance scattering
- 2000
-
Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 6203:3
-
Tidskriftsartikel (refereegranskat)abstract
- The level structure of the unbound nucleus N-11 has been studied by C-10+p elastic resonance scattering in inverse geometry with the LISE3 spectrometer at GANIL, using a C-10 beam with an energy of 9.0 MeV/ nucleon. An additional measurement was done at the A1200 spectrometer at MSU. The excitation function above the C-10+p threshold has been determined up to 5 MeV. A potential-model analysis revealed three resonance states at energies 1.27(-0.05)(+0.18) MeV (Gamma = 1.44 +/- 0.2 MeV), 2.01(-0.05)(+0.15) MeV (Gamma = 0.84 +/- 0.2 MeV), and 3.75 +/- 0.05 MeV (Gamma = 0.60 +/- 0.05 MeV) with the spin-parity assignments I-pi=1/2+,1/2,-,5/2+, respectively. Hence, N-11 is shown to have a ground state parity inversion completely analogous to its mirror partner Be-11. A narrow resonance in the excitation function at 4.33 +/- 0.05 MeV was also observed and assigned spin parity 3/2-.
|
|
4. |
- 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.
|
|
5. |
- Bergmann, U. C., et al.
(författare)
-
On the beta-decay of C-9
- 2001
-
Ingår i: Nuclear Physics A. - 0375-9474. ; 692:3-4, s. 427-450
-
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.
|
|
6. |
- 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.
|
|
7. |
- Fynbo, H. O. U., et al.
(författare)
-
New information on the beta-decay of Li-11 from Doppler broadened gamma lines
- 2004
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 736:1-2, s. 39-54
-
Tidskriftsartikel (refereegranskat)abstract
- The gamma-ray spectrum following beta-decay of Li-11 has been remeasured at the ISOLDE facility at CERN. Two new transitions were observed through the use of large Ge-detectors. Most gamma-decays will follow beta-delayed neutron emission. Information on the energy of the neutron is derived from analysis of the gamma line-shape and used to construct a partial decay scheme for Li-11. Lifetime values for the 1(-) and 2(-) levels in Be-10 are also derived. A new partial decay scheme is presented. (C) 2004 Elsevier B.V. All rights reserved.
|
|
8. |
- Fynbo, H. O. U., et al.
(författare)
-
The beta 2p decay mechanism of Ar-31
- 2000
-
Ingår i: Nuclear Physics A. - 0375-9474. ; 677, s. 38-60
-
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.
|
|
9. |
- Jeppesen, H. B., et al.
(författare)
-
News on beta delayed particle emission from Be-14
- 2002
-
Ingår i: Progress of Theoretical Physics Supplement. - 0375-9687. ; :146, s. 520-524
-
Konferensbidrag (refereegranskat)abstract
- Beta delayed charged particles from Be-14 have been measured and give an upper limit on beta delayed alpha particles of B(betaalpha)
|
|
10. |
|
|