| 1. |
- Miller, T. C., et al.
(författare)
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Particle astrophysics in antarctica
- 1996
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Ingår i: International School of Cosmic Ray Astrophysics: 10th Course: Toward the Millennium in Astrophysics: Problems and Prospects 16-26 Jun 1996. Erice, Italy. ; , s. 157-166
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Konferensbidrag (refereegranskat)
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| 2. |
- Gale, S. J., et al.
(författare)
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Band termination spectroscopy in 157Er
- 1995
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - 0954-3899. ; 21:2, s. 193-213
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Tidskriftsartikel (refereegranskat)abstract
- The level scheme of 157Er has been extended from a spin region where the nucleus behaves as a prolate rotor to a region where the spin is produced by the alignment of all or most of the available valence nucleons along the symmetry axis of a weakly deformed oblate shape. The level scheme was established at high spin using up to four-fold gamma -ray coincidences detected in the Eurogam spectrometer following the reaction 114Cd( 48Ca,5n)157Er at a bombarding energy of 210 MeV. Particularly favoured states have been established at IK=69/2+, 81/2+, 71/2+, 77/2-, 87-/2 and 89-/2. Specific single-particle configurations are assigned to these special states by comparison with cranked Nilsson-Strutinsky calculations. These states are related to structures observed in the neighbouring nuclei 158Er and 157Ho. These data provide the spectrum of single-particle states for the lowest lying valence orbitals above the 146Gd closed core.
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| 3. |
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| 4. |
- Joss, D T, et al.
(författare)
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Lifetime measurements of a triaxial band in Ce-133
- 1998
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Ingår i: Acta Physica Hungarica A. - 1219-7580 .- 1588-2675. ; 7:1, s. 111-112
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Tidskriftsartikel (refereegranskat)abstract
- The Doppler shift attenuation method has been used to determine the transition quadrupole moment of a triaxial band belonging to the gamma-soft nucleus, Ce-133. Doppler broadened lineshape (DBLS) analysis has revealed the magnitude of the Q(t) value to be similar to 2.4 eb. This contribution provides new information of (i) the transition quadrupole moment of this band (ii) the lifetimes of in-band and sidefeeding transitions and (iii) the relative deformations of coexisting nuclear shapes.
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| 5. |
- Joss, D T, et al.
(författare)
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Lifetime measurements of a triaxial band in Ce-133
- 1998
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 58:6, s. 3219-3222
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Tidskriftsartikel (refereegranskat)abstract
- Lifetimes of states within a triaxial band belonging to;the gamma-soft nucleus Ce-133 have been determined through a Doppler-broadened line shape analysis. A value, Q(t)approximate to 2.2 eb, has been found for the transition quadrupole moment which is considerably smaller than that of superdeformed structures (Q(t)approximate to 7.4 e b) in this mass region. The results are discussed in terms of deformation self-consistent calculations based on the total Routhian surface formalism. [S0556-2813(98)01912-8].
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| 6. |
- Svensson, C. E., et al.
(författare)
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Decay Out of the Doubly Magic Superdeformed Band in the N=Z Nucleus 60Zn
- 1999
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Ingår i: Physical Review Letters. - 1079-7114. ; 82:17, s. 3400-3403
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Tidskriftsartikel (refereegranskat)abstract
- The doubly magic superdeformed band in the N = Z nucleus Zn-60 has been identified. Linking transitions connecting this band to the yrast line provide the first spin, parity, and excitation energy measurements for superdeformed states in the A similar to 60 region. The stretched-E2 character and relatively large B(E2) values of these transitions suggest a nonstatistical decay-out process.
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| 7. |
- Svensson, C. E., et al.
(författare)
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Observation and Quadrupole Moment Measurement of the First Superdeformed Band in the A~60 Mass Region
- 1997
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Ingår i: Physical Review Letters. - 1079-7114. ; 79:7, s. 1233-1236
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Tidskriftsartikel (refereegranskat)abstract
- A high-spin rotational cascade of six gamma rays has been observed in Zn-62. The quadrupole moment of 2.7(-0.5)(+0.7) e b measured for this band corresponds to a deformation beta(2) = 0.45(-0.07)(+0.10). The properties of this band are in excellent agreement with calculations that predict high-spin superdeformed bands in Zn-62 with deformations beta(2) = 0.41-0.49. These results establish a new region of superdeformation for nuclei with neutron and proton numbers N, Z approximate to 30-32.
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| 8. |
- Svensson, C. E., et al.
(författare)
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Smooth Termination of Rotational Bands in 62Zn: Evidence for a Loss of Collectivity
- 1998
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Ingår i: Physical Review Letters. - 1079-7114. ; 80:12, s. 2558-2561
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Tidskriftsartikel (refereegranskat)abstract
- Two sets of strongly coupled rotational bands have been identified in Zn-62. These bands have been observed up to the terminating states of their respective configurations. Lifetime measurements indicate that the transition quadrupole moments in these bands decrease as termination is approached. These results establish the first terminating states of rotational bands in the A similar to 60 mass region and confirm the predicted loss of collectivity associated with smooth band termination.
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| 9. |
- Thorslund, I., et al.
(författare)
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Intruder bands in Te114 : Smooth band termination
- 1995
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Ingår i: Physical Review C. - 0556-2813. ; 52:6, s. 2839-2843
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Tidskriftsartikel (refereegranskat)abstract
- The nucleus Te114 has been studied in heavy-ion -ray spectroscopy experiments performed with the early implementation of the GAMMASPHERE multidetector array. Three rotational intruder bands have been observed up to high spins. The yrast band, involving the 4p2h (h11/2)2(g7/2)2(g9/2)-2 proton configuration, reaches I=48Latin small letter h with stroke at an excitation energy of 30.3 MeV, the highest observed spin connected by rays in this mass region. The band properties are interpreted in the framework of smooth band termination.
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| 10. |
- West, Jay B., et al.
(författare)
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Comparison and evaluation of retrospective intermodality image registration techniques
- 1997
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Ingår i: SPIE - The International Society for Optical Engineering. - : SPIE - International Society for Optical Engineering. ; , s. 332-347
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Konferensbidrag (refereegranskat)abstract
- All retrospective image registration methods have attached to them some intrinsic estimate of registration error. However, this estimate of accuracy may not always be a good indicator of the distance between actual and estimated positions of targets within the cranial cavity. This paper describes a project whose principal goal is to use a prospective method based on fiducial markers as a ’gold standard’ to perform an objective, blinded evaluation of the accuracy of several retrospective image-to-image registration techniques. Image volumes of three modalities – CT, MR, and PET – were taken of patients undergoing neurosurgery at Vanderbilt University Medical Center. These volumes had all traces of the fiducial markers removed, and were provided to project collaborators outside Vanderbilt, who then performed retrospective registrations on the volumes, calculating transformations from CT to MR and/or from PET to MR, and communicated their transformations to Vanderbilt where the accuracy of each registration was evaluated. In this evaluation the accuracy is measured at multiple ’regions of interest,’ i.e. areas in the brain which would commonly be areas of neurological interest. A region is defined in the MR image and its centroid C is determined. Then the prospective registration is used to obtain the corresponding point C’ in CT or PET. To this point the retrospective registration is then applied, producing C’ in MR. Statistics are gathered on the target registration error (TRE), which is the disparity between the original point C and its corresponding point C’. A second goal of the project is to evaluate the importance of correcting geometrical distortion in MR images, by comparing the retrospective TRE in the rectified images, i.e., those which have had the distortion correction applied, with that of the same images before rectification. This paper presents preliminary results of this study along with a brief description of each registration technique and an estimate of both preparation and execution time needed to perform the registration.
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| 11. |
- Yu, C. H., et al.
(författare)
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Comparison of Superdeformed Bands in 61Zn and 60Zn: Possible Evidence for T=0 Pairing
- 1999
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 60:3
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Tidskriftsartikel (refereegranskat)abstract
- The yrast superdeformed band in Zn-61 has been established using Si-28(Ar-36, 2pn)Zn-61 and Ca-40(Si-29, 2 alpha)Zn-61 fusion-evaporation reactions. The excitation energy of this band was determined via two transitions that link this band to the normally deformed states. Lifetime analysis of this band resulted in a quadrupole moment of Q(t) = 3.0 +/- (0.5)(0.4)e b, which corresponds to a deformation of beta(2) = 0.50+/-(0.07)(0.06). A comparison of the J((2)) dynamical moments of inertia of the yrast superdeformed band in Zn-61 with those in Zn-60 shows a nearly complete blocking of the observed alignment in Zn-60, indicating that T=0 proton-neutron pair correlations may be present in Zn-60. [S0556-2813(99)51109-6].
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| 12. |
- Andersson, T., et al.
(författare)
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High-spin States in the A=39 Mirror Nuclei 39Ca and 39K
- 1999
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Ingår i: European Physical Journal A. Hadrons and Nuclei. - 1434-6001. ; 6, s. 5-8
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Tidskriftsartikel (refereegranskat)abstract
- High-spin states of the mass A = 39 mirror pair K-39 and Ca-39 were investigated via the fusion-evaporation reaction Si-28+O-16 at 125 MeV beam energy. The GAMMASPHERE array in conjunction with the 4 pi charged-particle detector array MICROBALL and neutron detectors was used to detect gamma rays in coincidence with evaporated light particles. The results of the first high-spin study of the T-z = -1/2 nucleus Ca-39 are discussed in terms of mirror symmetry and compared to spherical shell-model calculations in the 1d(3/2)-1f(7/2) configuration space.
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| 13. |
- Gizon, J., et al.
(författare)
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Terminating bands in the doubly odd nucleus [Formula Presented]
- 1999
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 59:2, s. 570-574
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Tidskriftsartikel (refereegranskat)abstract
- High spin states have been populated in [Formula Presented] using the reaction [Formula Presented] at 130 MeV. The γ rays have been detected with the EUROGAM2 array. The level structure of [Formula Presented] has been investigated. Several bands have been identified and established over a wide range of spin. They are interpreted using the Nilsson-Strutinsky cranking formalism and explained in terms of band terminations. Their configurations are built from the valence particles and valence holes relative to a [Formula Presented] core: [Formula Presented] protons (and [Formula Presented] proton holes) and [Formula Presented] and [Formula Presented] neutrons. After [Formula Presented] is the second heavy nucleus and the first odd-odd nucleus in which configurations in the valence space are followed from low spin up to their termination.
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| 14. |
- Lane, G. J., et al.
(författare)
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Identification of excited states in doubly odd [Formula Presented]Sb : Smooth band termination
- 1997
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Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 55:5, s. 2127-2131
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in [Formula Presented]Sb have been identified for the first time in a series of [Formula Presented]-spectroscopy experiments using both thin and backed targets, including neutron-fold and recoil-mass measurements to provide unambiguous channel identification. The three decoupled intruder bands observed in [Formula Presented]Sb are based upon configurations involving 2p-2h excitations across the [Formula Presented] shell gap and show the features of smooth band termination. The yrast intruder band, which has been connected to the low-spin levels, is tentatively identified up to its predicted termination at [Formula Presented]. Excellent agreement with configuration-dependent cranked Nilsson-Strutinsky calculations is obtained for the high-spin states near termination.
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| 15. |
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| 16. |
- Pauwels, Romain A, et al.
(författare)
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Effect of inhaled formoterol and budesonide on exacerbations of asthma. Formoterol and Corticosteroids Establishing Therapy (FACET) International Study Group
- 1997
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Ingår i: New England Journal of Medicine. - 0028-4793. ; 337:20, s. 1405-1411
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The role of long-acting, inhaled beta2-agonists in treating asthma is uncertain. In a double-blind study, we evaluated the effects of adding inhaled formoterol to both lower and higher doses of the inhaled glucocorticoid budesonide. METHODS: After a four-week run-in period of treatment with budesonide (800 microg twice daily), 852 patients being treated with glucocorticoids were randomly assigned to one of four treatments given twice daily by means of a dry-powder inhaler (Turbuhaler): 100 microg of budesonide plus placebo, 100 microg of budesonide plus 12 microg of formoterol, 400 microg of budesonide plus placebo, or 400 microg of budesonide plus 12 microg of formoterol. Terbutaline was permitted as needed. Treatment continued for one year; we compared the frequency of exacerbations of asthma, symptoms, and lung function in the four groups. A severe exacerbation was defined by the need for oral glucocorticoids or a decrease in the peak flow to more than 30 percent below the base-line value on two consecutive days. RESULTS: The rates of severe and mild exacerbations were reduced by 26 percent and 40 percent, respectively, when formoterol was added to the lower dose of budesonide. The higher dose of budesonide alone reduced the rates of severe and mild exacerbations by 49 percent and 37 percent, respectively. Patients treated with formoterol and the higher dose of budesonide had the greatest reductions -- 63 percent and 62 percent, respectively. Symptoms of asthma and lung function improved with both formoterol and the higher dose of budesonide, but the improvements with formoterol were greater. CONCLUSIONS: In patients who have persistent symptoms of asthma despite treatment with inhaled glucocorticoids, the addition of formoterol to budesonide therapy or the use of a higher dose of budesonide may be beneficial. The addition of formoterol to budesonide therapy improves symptoms and lung function without lessening the control of asthma.
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