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1.	Aharonian, F., et al. (author) HESS Follow-up Observations of GRB 221009A 2023 In: Astrophysical Journal Letters. - : Institute of Physics Publishing (IOPP). - 2041-8205 .- 2041-8213. ; 946:1 Journal article (peer-reviewed)abstract GRB 221009A is the brightest gamma-ray burst (GRB) ever detected. To probe the very-high-energy (VHE; >100 GeV) emission, the High Energy Stereoscopic System (H.E.S.S.) began observations 53 hr after the triggering event, when the brightness of the moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from the third, fourth, and ninth nights after the initial GRB detection, after applying atmospheric corrections. The combined observations yield an integral energy flux upper limit of f(UL)(95%)=9.7x10(-12)ergcm(-2)s(-1) E-thr = 650 GeV. The constraints derived from the H.E.S.S. observations complement the available multiwavelength data. The radio to X-ray data are consistent with synchrotron emission from a single electron population, with the peak in the spectral energy distribution occurring above the X-ray band. Compared to the VHE-bright GRB 190829A, the upper limits for GRB 221009A imply a smaller gamma-ray to X-ray flux ratio in the afterglow. Even in the absence of a detection, the H.E.S.S. upper limits thus contribute to the multiwavelength picture of GRB 221009A, effectively ruling out an IC-dominated scenario.
2.	Aharonian, F., et al. (author) TeV flaring activity of the AGN PKS 0625-354 in November 2018 2024 In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 683 Journal article (peer-reviewed)abstract Most gamma-ray detected active galactic nuclei are blazars with one of their relativistic jets pointing towards the Earth. Only a few objects belong to the class of radio galaxies or misaligned blazars. Here, we investigate the nature of the object PKS 0625-354, its gamma-ray flux and spectral variability and its broad-band spectral emission with observations from H.E.S.S., Fermi-LAT, Swift-XRT, and UVOT taken in November 2018. The H.E.S.S. light curve above 200 GeV shows an outburst in the first night of observations followed by a declining flux with a halving time scale of 5.9 h. The gamma gamma-opacity constrains the upper limit of the angle between the jet and the line of sight to similar to 10 degrees. The broad-band spectral energy distribution shows two humps and can be well fitted with a single-zone synchrotron self Compton emission model. We conclude that PKS 0625-354, as an object showing clear features of both blazars and radio galaxies, can be classified as an intermediate active galactic nuclei. Multi-wavelength studies of such intermediate objects exhibiting features of both blazars and radio galaxies are sparse but crucial for the understanding of the broad-band emission of gamma-ray detected active galactic nuclei in general.
3.	Aharonian, F., et al. (author) Unveiling extended gamma-ray emission around HESS J1813-178 2024 In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 686 Journal article (peer-reviewed)abstract Context. HESS J1813-178 is a very-high-energy gamma-ray source spatially coincident with the young and energetic pulsar PSR J1813-1749 and thought to be associated with its pulsar wind nebula (PWN). Recently, evidence for extended high-energy emission in the vicinity of the pulsar has been revealed in the Fermi Large Area Telescope (LAT) data. This motivates revisiting the HESS J1813-178 region, taking advantage of improved analysis methods and an extended dataset. Aims. Using data taken by the High Energy Stereoscopic System (H.E.S.S.) experiment and the Fermi-LAT, we aim to describe the gamma-ray emission in the region with a consistent model, to provide insights into its origin. Methods. We performed a likelihood-based analysis on 32 hours of H.E.S.S. data and 12 yr of Fermi-LAT data and we fitted a spectromorphological model to the combined datasets. These results allowed us to develop a physical model for the origin of the observed.-ray emission in the region. Results. In addition to the compact very-high-energy gamma-ray emission centred on the pulsar, we find a significant yet previously undetected component along the Galactic plane. With Fermi-LAT data, we confirm extended high-energy emission consistent with the position and elongation of the extended emission observed with H.E.S.S. These results establish a consistent description of the emission in the region from GeV energies to several tens of TeV. Conclusions. This study suggests that HESS J1813-178 is associated with a gamma-ray PWN powered by PSR J1813-1749. A possible origin of the extended emission component is inverse Compton emission from electrons and positrons that have escaped the confines of the pulsar and form a halo around the PWN.
4.	Svensson, C. E., et al. (author) Collective rotational motion in the N=Z nucleus 36Ar 2001 In: Nuclear Physics A. - 0375-9474. ; 682:1-4, s. 1-11 Journal article (peer-reviewed)abstract A superdeformed rotational band has been identified in the N = Z nucleus 36Ar, firmly linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Lifetime measurements by the Doppler shift attenuation method establish a large low-spin deformation (β2 ≈ 0.46) and a decrease in the collectivity as the band approaches termination. Comparisons with cranked Nilsson-Strutinsky and large-scale spherical shell model calculations lead to a consistent description of the band based on a configuration in which four particles are promoted to the pf shell. With two major shells active for both protons and neutrons, yet a valence space dimension small enough to be approached from the shell model perspective, this band offers an excellent opportunity to investigate the microscopic structure of collective rotational motion in nuclei.
5.	Svensson, C. E., et al. (author) Superdeformation in the N = z Nucleus 36Ar : Experimental, deformed mean field, and spherical shell model descriptions 2000 In: Physical Review Letters. - 0031-9007. ; 85:13, s. 2693-2696 Journal article (peer-reviewed)abstract A superdeformed rotational band has been identified in 36Ar, linked to known low-spin states, and observed to its high-spin termination at Iπ = 16+. Cranked Nilsson-Strutinsky and spherical shell model calculations assign the band to a configuration in which four pf-shell orbitals are occupied, leading to a low-spin deformation β2 ≈ 0.45. Two major shells are active for both protons and neutrons, yet the valence space remains small enough to be confronted with the shell model. This band thus provides an ideal case to study the microscopic structure of collective rotational motion.
6.	Svensson, C. E., et al. (author) Decay Out of the Doubly Magic Superdeformed Band in the N=Z Nucleus 60Zn 1999 In: Physical Review Letters. - 1079-7114. ; 82:17, s. 3400-3403 Journal article (peer-reviewed)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.
7.	Ward, D., et al. (author) Band Structure of 68Ge 2001 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 63:1 Journal article (peer-reviewed)abstract The nucleus Ge-68 has been studied by gamma-ray spectroscopy following its population at high spin in the reaction Ca-40(S-32,4p) Ge-68. The reaction channel was selected with the Microball array and gamma rays were detected with the Gammasphere array. The level scheme is very complex, reflecting the many different, and presumably mixed, excitation modes in this nucleus. Nevertheless, there appear to be some simplifications in the spin range above 18 (h) over bar where we have identified a superdeformed band and several terminating bands. The results are compared with a cranked Nilsson-Strutinsky model without pairing.
8.	Döring, J., et al. (author) Band terminations in the valence space of 86Zr 2000 In: Physical Review C - Nuclear Physics. - 0556-2813. ; 61:3, s. 343101-343106 Journal article (peer-reviewed)abstract High-spin states in 86Zr up to 30+ and 27- were observed via the 58Ni(32S,4p) reaction at 135 MeV beam energy using the combined GAMMASPHERE and MICROBALL systems. Calculations performed with the configuration-dependent shell-correction approach show that these states are built from six g9/2 neutrons and at most four protons excited from the p1/2,p3/2,f5/2 subshells to the g9/2 subshell at small deformation. The highest observed states at 27- and 30+ are interpreted as band-terminating states with the latter having the highest spin available in the valence space for 86Zr.
9.	Svensson, C. E., et al. (author) Smooth Termination of Rotational Bands in 62Zn: Evidence for a Loss of Collectivity 1998 In: Physical Review Letters. - 1079-7114. ; 80:12, s. 2558-2561 Journal article (peer-reviewed)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.
10.	Bruce, A. M., et al. (author) Two-neutron alignment and shape changes in As-69 2000 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 6202:2 Journal article (peer-reviewed)abstract The nucleus As-69 was Studied using the Ca-40(S-32,3p)As-69 reaction at a beam energy of 105 MeV. An extension of the band built on the g(9/2) orbital was observed to exhibit a band crossing at a rotational frequency of 0.511 MeV with an associated alignment of 7 (h) over bar. This alignment is interpreted as being due to a pair of g(9/2) neutrons. Total Routhian surface calculations have been carried out which confirm that the shape of this nucleus changes from oblate at low spin to a triaxial prolate shape at intermediate spin.
11.	Chiara, C. J., et al. (author) Probing sd-fp Cross-shell Interactions via Terminating Configurations in 42Sc,43Sc 2007 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 75:5 Journal article (peer-reviewed)abstract An experimental study of the lower fp-shell nuclei Sc-42,Sc-43 was performed via alpha pn and alpha p evaporation, respectively, from Ne-20 + Si-28 and Mg-24 + Mg-24 fusion-evaporation reactions. The experiments were conducted with the Gammasphere and Microball detector arrays. The level schemes of both nuclei have been extended considerably. Terminating states associated with the f(7/2)(n) and d(3/2)(-1)f(7/2)(n+1) configurations were identified in each nuclide and incorporated into detailed comparisons with neighboring nuclei and with shell model calculations. The energy differences between the terminating states provide a test of the sd-fp cross-shell interactions in these calculations.
12.	Ideguchi, E., et al. (author) Superdeformation in the Doubly Magic Nucleus 40Ca 2001 In: Physical Review Letters. - 1079-7114. ; 87:22 Journal article (peer-reviewed)abstract A rotational band with seven gamma -ray transitions between states with spin 2 (h) over bar and 16 (h) over bar has been observed in the doubly magic, self-conjugate nucleus Ca-40(20)20. The measured transition quadrupole moment of 1.80(-0.29)(+0.39)eb indicates a superdeformed shape with a deformation beta (2) = 0.59(-0.07)(+0.11). The features of this band are explained by cranked relativistic mean field calculations to arise from an 8-particle 8-hole excitation.
13.	Rudolph, Dirk, et al. (author) Shell-model Influence in the Rotational Nucleus 86Mo 1996 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 54:1, s. 117-124 Journal article (peer-reviewed)abstract High-spin states in Mo-86 were studied by means of the fusion evaporation reaction Ni-58(S-32,2p2n) Mo-86 at 135 MeV beam energy. Charged-particle-gamma gamma and -gamma gamma gamma coincidences recorded with the early implementation of the GAMMASPHERE array and the MICROBALL charged-particle detection system were used to largely extend the level scheme of the T-tau=1 nucleus Mo-86 to a possible spin of I=24h at 13 MeV excitation energy. The excitation scheme is compared to neighboring nuclei. There is evidence for enhanced shell-model influence in the 4 quasiparticle region (I=12-16h). The observed (pi=+,alpha=0) sequence at spin I greater than or equal to 16 h appears to be associated with a triaxial collective rotational band. This interpretation is supported by calculations within the configuration-dependent shell-correction approach with the cranked Nilsson potential.
14.	Svensson, C. E., et al. (author) Observation and Quadrupole Moment Measurement of the First Superdeformed Band in the A~60 Mass Region 1997 In: Physical Review Letters. - 1079-7114. ; 79:7, s. 1233-1236 Journal article (peer-reviewed)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.
15.	Yu, C. H., et al. (author) Comparison of Superdeformed Bands in 61Zn and 60Zn: Possible Evidence for T=0 Pairing 1999 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 60:3 Journal article (peer-reviewed)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].
16.	Yu, C. H., et al. (author) Superdeformed and Highly Deformed Bands in 65Zn and Neutron-proton Interactions in Zn Isotopes 2000 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 62:4 Journal article (peer-reviewed)abstract Superdeformed and highly deformed rotational bands were established in Zn-65 using the Ca-40(Si-29,4p)Zn-65 reaction, and averaged quadrupole moments were measured for two of these bands. The configurations of these bands were assigned based on Hartree-Fock calculations. One of the three bands exhibits at low (h) over bar omega a rise in the J((2)) dynamic moments of inertia that is similar to the alignment gain observed in Zn-60. A comparison of the rotational band configurations and their J((2)) moments of inertia for light Zn isotopes suggests that the rise in J((2)) is most likely caused by np interactions associated with the valence protons and neutrons occupying the g(9/2) intruder orbits.
17.	Chiara, CJ, et al. (author) Transition Quadrupole Moments in the Superdeformed Band of 40Ca 2003 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 67:4 Journal article (peer-reviewed)abstract The transition quadrupole moments Q(t) for the superdeformed band in Ca-40 have been determined through thin-target Doppler-shift attenuation analyses. A best-fit value of Q(t)=1.30+/-0.05 e b is obtained when a single value is assumed for the entire band. Fitting separate quadrupole moments for in-band transitions decaying from the high-spin states and the presumably admixed low-spin states results in Q(t)(high)= 1.81(-0.26)(+0.41) e b and Q(t)(low)=1.18(-0.05)(+0.06) e b, respectively. Q(t) values extracted for individual transitions in a Doppler-broadened line-shape analysis also indicate smaller Q(t) values at lower spins. These results are consistent with the interpretation of this band as an eight-particle-eight-hole superdeformed band with a significant admixture of less-collective configurations at low spins.
18.	Ideguchi, E, et al. (author) Superdeformation in the doubly magic nucleus Ca-40(20)20 2001 In: PHYSICAL REVIEW LETTERS. - : AMERICAN PHYSICAL SOC, COLLEGE PK. - 0031-9007. ; 87:222501, s. 2501- Journal article (peer-reviewed)abstract A rotational band with seven gamma -ray transitions between states with spin 2 (h) over bar and 16 (h) over bar has been observed in the doubly magic, self-conjugate nucleus Ca-40(20)20. The measured transition quadrupole moment of 1.80(-0.29)(+0.39)eb in
19.	Lipoglavsek, M, et al. (author) 100Sn Core Excitations in 102In 2002 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:2 Journal article (peer-reviewed)abstract Nuclei in the vicinity of the doubly-magic Sn-100 nucleus have been studied, and an extended level scheme for In-102 has been established. The level structure comprises both the negative parity states involving the nuh(11/2) orbital, and levels due to the breakup of the doubly-magic Sn-100 core. Results of a large-scale shell model calculation, using realistic and empirical effective interactions with Sr-88 as a core, are in very good agreement with the experimental data.
20.	Lipoglavsek, M, et al. (author) Breakup of the Doubly Magic 100Sn Core 2002 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 66:1 Journal article (peer-reviewed)abstract Level schemes of Cd-99(48)51 and In-101(49)52 nuclei have been extended to high spin. The breakup of the doubly magic Sn-100 core has been observed. Large-scale shell model calculations based on realistic nucleon-nucleon interactions are in good agreement with the experimental data. These results provide a reliable basis to predict nuclear structure properties in Sn-100 and its neighbors. For example, the size of the N=50 shell gap and the energy of the first excited state in Sn-101 have been deduced.
21.	Lipoglavsek, M, et al. (author) Excited States of the Proton Emitter 105Sb 2002 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:5 Journal article (peer-reviewed)abstract Excited states in the proton emitter Sb-105 have been investigated for the first time. The nucleus was populated in the reaction Cr-50(Ni-58,1p2n). The GAMMASPHERE Ge-detector array was used together with Microball and the Neutron Shell for selection of the reaction channel. The experimental level scheme agrees well with results of a shell model calculation that uses realistic effective interactions derived from the CD-Bonn nucleon-nucleon interaction and Sn-100 as a closed-shell core.
22.	Lipoglavsek, M., et al. (author) First Observation of Excitation Across the 100Sn Core 2001 In: Nuclear Physics, Section A. - 0375-9474. ; 682, s. 399-403 Journal article (peer-reviewed)abstract Excited states of nuclei near the doubly-magic nucleus Sn-100 were studied with the Ni-58+Cr-50 reaction. The experimental setup consisted of the GAMMASPHERE array augmented with light charged-particle and neutron detectors. Excited states were identified for the first time in the proton emitting nucleus Sb-105. Excitations across the N=Z=50 doubly closed shell were observed in Cd-99 and In-101. Some results of large-scale shell-model calculations are discussed.
23.	Sarantites, D. G., et al. (author) Triaxial superdeformed bands in [Formula Presented] 1998 In: Physical Review C - Nuclear Physics. - 0556-2813. ; 57:1, s. 1-5 Journal article (peer-reviewed)abstract Four new superdeformed bands have been found in the nucleus [Formula Presented]. The good agreement between experiment and configuration-dependent shell correction calculations suggests that three of the bands have triaxial superdeformed shapes. Such unique features in mass [Formula Presented] superdeformed bands have been predicted, but not observed experimentally until now. A fourth band in [Formula Presented] is interesting due to a fairly constant and unusually high dynamic moment of inertia. Possible interpretations of this structure are discussed.
24.	Sun, H., et al. (author) New Band Structures and an Unpaired Crossing in 78Kr 1999 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 59:2, s. 655-664 Journal article (peer-reviewed)abstract High-spin states in Kr-78 were studied using the Ni-58(Na-23,3p) reaction at 70 MeV and the Ni-58(Si-23,alpha 4p) reaction at 130 MeV. Prompt gamma-gamma coincidences were measured using the Pitt-FSU detector array and the GAMMASPHERE-MICROBALL array. Results from these experiments have led to 26 new excitation levels, some of which have been grouped into 3 new bands. Spins were assigned based on directional correlations of oriented nuclei. Two of the new negative-parity bands appear to form a signature-partner pair based on a two-quasineutron structure, in contrast to the previously known two-quasiproton negative-parity bands. A forking has been observed at the 24(+) state in the yrast band, which calculations suggest may result from an unpaired crossing. The available evidence suggests oblate shapes in the yrast band coexist with prolate shapes in the negative-parity bands. [S0556-2813(99)04602-6].
25.	Sylvan, G N, et al. (author) Deformation driving intruder orbitals in Kr-77 1997 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 56:2, s. 772-781 Journal article (peer-reviewed)abstract High-spin states in Kr-77 were identified via analysis of prompt gamma-gamma coincidences in the Ni-58(Si-29,2 alpha 2p) reaction at 128 MeV at the Gammasphere facility. Evaporation channel selection was achieved using the 95 element Microball charged-particle detector. 27 new states and 42 new transitions were found, The positive-parity bands were confirmed and the alpha=-1/2 band extended to 39/2(+). The negative-parity signature pair was extended to 31/2(-) and 37/2(-). Two new high-lying negative-parity bands were found extending from a state of spin I = 15/2 and energy 2.6 MeV to 17.4 MeV at I = (55/2). The new bands appear highly deformed and become yrast at high spin. A three-quasiparticle structure based on deformation driving, low-K unique-parity and intruder orbitals is suggested for them.
26.	Andersson, Lise-Lotte, et al. (author) Extensive Gamma-ray Spectroscopy of Normally and Superdeformed Structures in 61Cu 2008 In: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 36:3, s. 251-278 Journal article (peer-reviewed)abstract A largely extended experimental knowledge of the Cu-61(29)32 nucleus has been obtained from three experiments. Excited states in Cu-61 were produced via the fusion-evaporation reaction Si-28(Ar-36, 3p)Cu-61. In addition to the Ge array GAMMASPHERE, neutron and charged-particle detectors placed around the target position were used for high-performance particle spectroscopy. The constructed level scheme includes more than 160 energy levels and 320 gamma-ray transitions belonging to both normally deformed as well as superdeformed rotational structures. The multipolarities have been determined for the gamma-ray transitions and as a result spin-parity assignments are given for nearly all energy levels. Experimental results in the normally deformed region are compared with predictions from large-scale shell model calculations. The collective structures are compared with results from cranked Nilsson-Strutinsky calculations. The results reveal the need to modify the standard Nilsson parameters in the mass A similar to 60 region.
27.	Andersson, T., et al. (author) High-spin States in the A=39 Mirror Nuclei 39Ca and 39K 1999 In: European Physical Journal A. Hadrons and Nuclei. - 1434-6001. ; 6, s. 5-8 Journal article (peer-reviewed)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.
28.	Andreoiu, Corina, et al. (author) Yrast Superdeformed Band in 59Cu 2000 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 62:5, s. 513011-513015 Journal article (peer-reviewed)abstract High-spin states in 59Cu were populated using the fusion-evaporation reactions 28Si+40Ca at a beam energy of 125 MeV and 36Ar+28Si at a beam energy of 143 MeV. The Gammasphere array in conjunction with ancillary detector systems allowed for the identification of a superdeformed rotational band in 59Cu, which was firmly linked to low-spin yrast states. Using directional correlations of oriented states, a spin-parity assignment of Iπ = 25/2+ to the band head was possible. The average quadrupole moment of the band is measured to be Qt = (2.24±0.40) e b. The characteristics of the band are compared to neighboring nuclei and predictions of different mean-field theories.
29.	CRISTANCHO, F, et al. (author) MULTIPLE SUPERDEFORMED BANDS IN SR-81 1995 In: Physics Letters B. - 0370-2693 .- 1873-2445. ; 357:3, s. 281-286 Journal article (peer-reviewed)abstract Four superdeformed bands extending over five to twelve transitions have been identified in Sr-81 from a study With the Gammasphere array and the Microball charged-particle array, One of the bands shows an upbend in the dynamic moment of inertia at a rotational frequency of 1.2 MeV and all bands exhibit a nearly constant moment of inertia below that frequency.
30.	Gellanki, Jnaneswari, et al. (author) Characterization of Superdeformed Bands in 62Zn 2009 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:5 Journal article (peer-reviewed)abstract Combined data from four fusion-evaporation reaction experiments were utilized to investigate deformed and superdeformed structures in Zn-62(30)32. Combination of the Gammasphere gamma-ray spectrometer and ancillary particle detection systems allowed for the connection of rotational bands to well-known, low-lying excited states in Zn-62, as well as spectroscopy of discrete high-spin states reaching excitation energies of E-x=42.5 MeV. Four well- or superdeformed bands in Zn-62 are characterized and described by means of cranked Nilsson-Strutinsky calculations.
31.	HUA, PF, et al. (author) SEARCH FOR HYPERDEFORMATION IN GD-146 USING THE MICROBALL AND GAMMASPHERE 1994 In: Abstracts of Papers of the American Chemical Society. - 0065-7727. ; 208, s. 12-NUCL Journal article (peer-reviewed)
32.	Johansson, Emma, et al. (author) Prompt Proton Decay and Deformed Bands in 56Ni 2008 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:6 Journal article (peer-reviewed)abstract High-spin states in the doubly magic N=Z nucleus Ni-56 have been investigated with three fusion-evaporation reaction experiments. New gamma-ray transitions are added, and a confirmation of a previously suggested prompt proton decay from a rotational band in Ni-56 into the ground state of Co-55 is presented. The rotational bands in Ni-56 are discussed within the framework of cranked Nilsson-Strutinsky calculations.
33.	Johansson, Emma, et al. (author) Thorough Gamma-ray and Particle Decay Investigations of 58Ni 2009 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:1 Journal article (peer-reviewed)abstract The combined data from three fusion-evaporation reaction experiments have been utilized to investigate the semi-magic nucleus Ni-58(28)30. To detect gamma rays in coincidence with evaporated particles, the Ge-detector array Gammasphere was used in conjunction with the charged-particle detectors Microball and LuWuSiA (the Lund Washington University Silicon Array), and a neutron detector array. The results yield a significantly extended level scheme of Ni-58 comprising some 340 gamma-ray transitions and include a total of at least 14 discrete particle decays into excited states of the daughter nuclei Fe-54 and Co-57. The level scheme is compared with large-scale shell-model calculations and cranked Nilsson-Strutinsky calculations.
34.	LAFOSSE, DR, et al. (author) CHARACTERIZATION OF THE FIRST SUPERDEFORMED BAND IN THE A-APPROXIMATE-TO-80 REGION 1995 In: Physics Letters B. - 0370-2693 .- 1873-2445. ; 354:1-2, s. 34-40 Journal article (peer-reviewed)abstract The recently discovered superdeformed band in one of the strontium isotopes has been identified as belonging to Sr-83 from a study with the Gammasphere array and the Microball charged-particle detector system. From its decay pattern, a spin of (81 +/- 2)/2 ($) over bar h is deduced for the highest level of this band. Evidence for very fast transition rates and agreement of the characteristics of this band with the theoretical predictions establish the yrast superdeformed nature of this band in Sr-83.
35.	LaFosse, D R, et al. (author) Search for hyperdeformation in Gd-146,Gd-147 1996 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 54:4, s. 1585-1588 Journal article (peer-reviewed)abstract A search was undertaken to look for evidence of hyperdeformation in Gd-146,Gd-147. Three experiments employing Gammasphere for gamma-ray detection coupled with the Microball for channel selection via charged particle detection were carried out with increasing detection sensitivity and statistics. No definitive evidence for band structures that could be assigned to hyperdeformation could be found. Candidates previously reported are shown not to have properties consistent with a band structure.
36.	Lerma, F., et al. (author) Superdeformed bands in Sr80-83, Y82-84, Zr-83,Zr-84 : Transition quadrupole moments, moments of inertia, and configuration assignments 2003 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 67:4, s. 044310- Journal article (peer-reviewed)abstract Multiple superdeformed bands in the nuclei Sr80-83, Y82-84, and Zr-83,Zr-84 have been studied in a backed-target experiment, using the Gammasphere and the Microball 4pi detector arrays. For 15 bands in these nuclei, average transition quadrupole moments have been measured with high accuracy, using the Doppler-shift attenuation method. Among these are the newly observed superdeformed bands in Y-83,Y-84, which are isospectral with the bands in Sr-82,Sr-83. These isospectral bands have nearly identical transition quadrupole moments. Two of the bands in Sr-81 interact and cross transitions between them are observed. The present measurements place stringent conditions on configuration assignments for the bands obtained from two types of mean-field calculations, leading to a consistent understanding of the mass similar to80 superdeformed bands. The assignments for different bands arise from one or more nucleons occupying the N-0=5h(11/2) intruder orbital.
37.	Rudolph, Dirk, et al. (author) Rotational Bands in the Doubly Magic Nucleus 56Ni 1999 In: Physical Review Letters. - 1079-7114. ; 82:19, s. 3763-3766 Journal article (peer-reviewed)abstract Structures of the medium- to high-spin states in the doubly magic nucleus Ni-56 have been investigated using the reaction Si-28(Ar-36, 2 alpha) and the gamma-ray spectrometer Gammasphere in conjunction with the 4 pi charged-particle detector array Microball. Two well-deformed rotational bands have been identified. There is evidence that one of the bands, which is identical to a sequence in the odd-odd neighbor Cu-58, partially decays via proton emission into the ground state of Co-55. Predictions of extensive large-scale shell-model and cranked Hartree-Fock and Hartree-Fock-Bogolyubov calculations are compared with the experimental data.
38.	Rudolph, Dirk, et al. (author) Spherical and Deformed High-spin states in 38Ar 2002 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:3 Journal article (peer-reviewed)abstract Excited states in Ar-38 have been investigated by means of the heavy-ion fusion-evaporation reaction Si-28 +O-16. The level scheme reveals a subtle interplay between spherical, deformed, and superdeformed shapes. Large-scale shell-model calculations in the sd-fp space are invoked to study the microscopic aspects of deformation and shape changes.
39.	Torres, D. A., et al. (author) Deformations and Magnetic Rotations in the 60Ni Nucleus 2008 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:5 Journal article (peer-reviewed)abstract Data from three experiments using the heavy-ion fusion evaporation-reaction Ar-36+Si-28 have been combined to study high-spin states in the residual nucleus Ni-60, which is populated via the evaporation of four protons from the compound nucleus Ge-64. The GAMMASPHERE array was used for all the experiments in conjunction with a 4 pi charged-particle detector arrays (MICROBALL, LUWUSIA) and neutron detectors (NEUTRON SHELL) to allow for the detection of. rays in coincidence with the evaporated particles. An extended Ni-60 level scheme is presented, comprising more than 270 gamma-ray transitions and 110 excited states. Their spins and parities have been assigned via directional correlations of gamma rays emitted from oriented states. Spherical shell-model calculations in the fp-shell characterize some of the low-spin states, while the experimental results of the rotational bands are analyzed with configuration-dependent cranked Nilsson-Strutinsky calculations.
40.	Yu, CH, et al. (author) Rotational Bands with Terminating Properties in 59Ni 2002 In: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:6 Journal article (peer-reviewed)abstract Highly-deformed rotational bands were established in Ni-59 using the Ca-40(Si-29,2p2alpha)Ni-59 reaction. Lifetime measurements indicate that transition quadrupole moments of two of these bands decrease as they smoothly approach their maximum-spin states. The configurations of these bands as well as their band-terminating features are discussed based on configuration-dependent cranked Nilsson-Strutinsky calculations. These calculations indicate that, unlike similar bands observed previously in the region, the two bands in Ni-59 maintain significant collectivity at their I=I-max states.

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