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1.	Loisel, J., et al. (författare) Expert assessment of future vulnerability of the global peatland carbon sink 2021 Ingår i: Nature Climate Change. - : Springer Science and Business Media LLC. - 1758-678X .- 1758-6798. ; 11:1, s. 70-77 Tidskriftsartikel (refereegranskat)abstract Peatlands are impacted by climate and land-use changes, with feedback to warming by acting as either sources or sinks of carbon. Expert elicitation combined with literature review reveals key drivers of change that alter peatland carbon dynamics, with implications for improving models. The carbon balance of peatlands is predicted to shift from a sink to a source this century. However, peatland ecosystems are still omitted from the main Earth system models that are used for future climate change projections, and they are not considered in integrated assessment models that are used in impact and mitigation studies. By using evidence synthesized from the literature and an expert elicitation, we define and quantify the leading drivers of change that have impacted peatland carbon stocks during the Holocene and predict their effect during this century and in the far future. We also identify uncertainties and knowledge gaps in the scientific community and provide insight towards better integration of peatlands into modelling frameworks. Given the importance of the contribution by peatlands to the global carbon cycle, this study shows that peatland science is a critical research area and that we still have a long way to go to fully understand the peatland-carbon-climate nexus.
2.	Wang, F., et al. (författare) Reinvestigation of the excited states in the proton emitter Lu-151 : Particle-hole excitations across the N = Z=64 subshell 2017 Ingår i: Physical Review C. - : American Physical Society. - 2469-9985 .- 2469-9993. ; 96:6 Tidskriftsartikel (refereegranskat)abstract The excited states of the proton emitter Lu-151 were reinvestigated in a recoil-decay tagging experiment at the Accelerator Laboratory of the University of Jyvaskyla (JYFL). The level scheme built on the ground state of 151Lu was updated with five new y-ray transitions. Large-scale shell model calculations were carried out in the model space consisting of the neutron and proton orbitals 0g(7/2), Id(5/2), Id(3/2), 2s(1/2), and Oh(1/2) with the optimized monopole interaction in order to interpret the experimental level scheme of Lu-151. It is found that the excitation energies of states above the 27/2(-) and 23/2(+) isomeric levels in Lu-151 can be sensitive to excitations from g(7/2) and d(5/2) to single-particle orbitals above N = Z = 64.
3.	Wang, F., et al. (författare) Spectroscopic factor and proton formation probability for the d3/2 proton emitter 151mLu 2017 Ingår i: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 770, s. 83-87 Tidskriftsartikel (refereegranskat)abstract The quenching of the experimental spectroscopic factor for proton emission from the short-lived d3/2 isomeric state in 151mLu was a long-standing problem. In the present work, proton emission from this isomer has been reinvestigated in an experiment at the Accelerator Laboratory of the University of Jyväskylä. The proton-decay energy and half-life of this isomer were measured to be 1295(5) keV and 15.4(8) μs, respectively, in agreement with another recent study. These new experimental data can resolve the discrepancy in the spectroscopic factor calculated using the spherical WKB approximation. Using the R-matrix approach it is found that the proton formation probability indicates no significant hindrance for the proton decay of 151mLu.
4.	Wadsworth, R., et al. (författare) THE NORTHWEST FRONTIER : SPECTROSCOPY OF N similar to Z NUCLEI BELOW MASS 100 2009 Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 40:3, s. 611-620 Tidskriftsartikel (refereegranskat)abstract The spectroscopy and structure of excited states of N similar to Z nuclei in the mass 70-100 region has been investigated using two techniques. In the A similar to 70-80 region fusion evaporation reactions coupled with the recoil-beta-tagging method have been employed at Jyvaskyla to study low-lying states in odd-odd N = Z nuclei. Results from these and other data for known odd-odd nuclei above mass 60 will be discussed. In the heavier mass 90 region a fragmentation experiment has been performed using the RIS-ING/FRS setup at GSI. This experiment was primarily aimed at searching for spin gap isomers in nuclei around A similar to 96. The objectives of the latter experiment will be discussed.
5.	Bianco, L., et al. (författare) Discovery of W-157 and Os-161 2010 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 690:1, s. 15-18 Tidskriftsartikel (refereegranskat)abstract The nuclides W-157 and Os-161 have been discovered ill reactions of Ni-58 ion beams with a Cd-106 target. The Os-161 alpha-decay energy and half-life were 6890 +/- 12 keV and 640 +/- 60 mu s. The daughter W-157 nuclei beta-decayed with a half-life of 275 +/- 40 ms, populating both low-lying alpha-decaying states in Ta-157, which is consistent with a 7/2(-) ground state in W-157. Fine structure observed in the alpha decay of Os-161 places the lowest excited state in W-157 with 1(pi) = 9/2(-) at 318 +/- 30 key. The branching ratio of 5.5(-2.2)(+3.1)% indicates that Os-161 also has a 7/2(-) ground state. Shell-model calculations analysing the effects of monopole shifts and a tensor force on the relative energies of 2f(7/2) and 1h(9/2) neutron states in N = 83 isotones are presented. (C) 2010 Elsevier B.V. All rights reserved.
6.	Darby, I. G., et al. (författare) Decay of the high-spin isomer in Re-160 : Changing single-particle structure beyond the proton drip line 2011 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 695:1-4, s. 78-81 Tidskriftsartikel (refereegranskat)abstract A new high-spin isomeric state (t(1/2) = 2.8 +/- 0.1 mu s) in Re-160 has been identified. This high-spin isomer is unique in that it only decays by gamma-decay and not by proton or alpha-particle emission as is the case in every other proton emitter between Z = 64 and 80. Shell model calculations indicate how the convergence of the h(9/2) and f(7/2) neutron levels in this region could open up a gamma-decay path from the high-spin isomer to the low-spin ground state of 160Re. providing a natural explanation for this anomalous absence of charged-particle emission. The consequences of these observations for future searches for proton emission from even more exotic nuclei and in-beam spectroscopic studies are considered.
7.	Darby, I. G., et al. (författare) Precision measurements of proton emission from the ground states of Ta-156 and Re-160 2011 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 83:6, s. 064320- Tidskriftsartikel (refereegranskat)abstract The decays of the pi d(3/2) ground states of Ta-156 and Re-160 have been studied in detail using the GREAT spectrometer. More than 7000 Re-160 nuclei were produced in reactions of 290- and 300-MeV Ni-58 ions with an isotopically enriched Cd-106 target and separated in flight using the RITU separator. The proton and alpha decays of the pi d(3/2) level were confirmed and the half-life and branching ratios of this state were determined with improved precision to be t(1/2) = 611 +/- 7 mu s and b(p) = 89 +/- 1% and b(alpha) = 11 +/- 1%, respectively. The alpha-decay branch populated the ground state of Ta-156, allowing improved values for the proton-decay energy and half-life to be obtained (E-p = 1011 +/- 5 keV; t(1/2) = 106 +/- 4 ms). The beta decay of this level was identified for the first time and a branching ratio of b(beta) = 29 +/- 3% was deduced. The spectroscopic factors deduced from these measurements are compared with predictions.
8.	Davis-Merry, T. R., et al. (författare) Collective excitations in the transitional nuclei Re-163 and Re-165 2015 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 91:3 Tidskriftsartikel (refereegranskat)abstract Excited states in the neutron-deficient nuclei (163)(75) Re-88 and (165)(75) Re-90 were populated in the Cd-106(Ni-60, p2n gamma) and Mo-92(Kr-78, 3p2n gamma) fusion-evaporation reactions at bombarding energies of 270 and 380 MeV, respectively.. rays were detected at the target position using the JUROGAM spectrometer while recoiling ions were separated in-flight by the RITU gas-filled recoil separator and implanted in the GREAT spectrometer. The energy level schemes for Re-163 and Re-165 were identified using recoil-decay correlation techniques. At low spin, the yrast bands of these isotopes consist of signature partner bands based on a single pi h(11/2) quasiproton configuration. The bands display large energy splitting consistent with the soft triaxial shape typical of transitional nuclei above N = 82. The configurations of the excited states are proposed within the framework of the cranked shell model.
9.	Ertoprak, Aysegul, et al. (författare) Evidence for octupole collectivity in 172Pt 2020 Ingår i: European Physical Journal A. - : Springer. - 1434-6001 .- 1434-601X. ; 56:2 Tidskriftsartikel (refereegranskat)abstract Excited states in the extremely neutron-deficient nucleus 172Pt were populated via 96Ru(78Kr,2p) and 92Mo(83Kr,3n) reactions. The level scheme has been extended up to an excitation energy of ~ 5 MeV and tentative spin-parity assignments up to Iπ = 18+. Linear polarization and angular distribution measurements were used to determine the electromagnetic E1 character of the dipole transitions connecting the positive-parity ground-state band with an excited side-band, firmly establishing it as a negative-parity band. The lowest member of this negative-parity structure was firmly assigned spin-parity 3-. In addition, we observed an E3 transition from this 3- state to the ground state, providing direct evidence for octupole collectivity in 172Pt. Large-scale shell model (LSSM) and total Routhian surface (TRS) calculations have been performed, supporting the interpretation of the 3- state as a collective octupole-vibrational state.
10.	Joss, D. T., et al. (författare) Discovery of the proton emitting nucleus 159Re 2007 Ingår i: Proton Emitting Nuclei and Related Topics. - : American Institute of Physics (AIP). - 9780735404755 ; , s. 28-33 Konferensbidrag (refereegranskat)abstract The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni, p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 μs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered.
11.	Joss, D. T., et al. (författare) Evolving collective structures in the transitional nuclei W-162 and W-164 2016 Ingår i: PHYSICAL REVIEW C. - : American Physical Society. - 2469-9985. ; 93:2 Tidskriftsartikel (refereegranskat)abstract Excited states in the neutron-deficient nuclides(74)(162)W(88) and W-164(74)90 were investigated by using the gamma-ray spectrometer Jurogam. A change in structure is apparent from the first rotational alignments in W-162 and W-164, whose rotationally aligned bands are interpreted as nu(h(9/2))(2) and nu(i(13/2))(2) configurations, respectively. The level schemes have been extended using recoil (-decay) correlations with the observation of excited collective structures. Configuration assignments have been made on the basis of comparisons of the deduced aligned angular momentum, as a function of rotational frequency, with the predictions of the cranked shell model.
12.	Joss, D. T., et al. (författare) Probing the limit of nuclear existence : Proton emission from Re-159 2006 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 641:1, s. 34-37 Tidskriftsartikel (refereegranskat)abstract The observation of the new nuclide Re-159(75)84 provides important insights into the evolution of single-particle structure and the mass surface in heavy nuclei beyond the proton drip line. This nuclide, 26 neutrons away from the nearest stable rhenium isotope, was synthesised in the reaction Cd-106(Ni-58, p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (E-p = 1805 +/- 20 keV) and decay half-life (t(1/2) = 21 +/- 4 mu s) with values calculated using the WKB method indicate that the proton is emitted from an h(11/2) state. The implications of these results for future experimental investigations into even more proton unbound nuclei using in-flight separation techniques are considered.
13.	Joss, D. T., et al. (författare) The influence of quasineutron configurations on 161Ta and nearby odd-A nuclei 2011 Ingår i: AIP Conf. Proc.. - : AIP. - 9780735409835 ; , s. 43-48 Konferensbidrag (refereegranskat)abstract Several strongly coupled bands in the neutron-deficient nucleus 161Ta have been identified and quasiparticle configuration assignments have been made on the basis of rotational alignments and cranked shell model calculations. The level scheme elucidated for 161Ta highlights the competition between the ν(h 9/2) and ν(i 13/2) orbitals to form the yrast spectrum. The band structures in 161Ta also provide new insights into the structural features of other heavy odd-A nuclei populated with much lower reaction cross sections in this region at the proton drip line.
14.	Ketelhut, S., et al. (författare) gamma-Ray Spectroscopy at the Limits : First Observation of Rotational Bands in Lr-255 2009 Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:21, s. 212501- Tidskriftsartikel (refereegranskat)abstract The rotational band structure of Lr-255 has been investigated using advanced in-beam gamma-ray spectroscopic techniques. To date, Lr-255 is the heaviest nucleus to be studied in this manner. One rotational band has been unambiguously observed and strong evidence for a second rotational structure was found. The structures are tentatively assigned to be based on the 1/2(-)[521] and 7/2(-)[514] Nilsson states, consistent with assignments from recently obtained alpha decay data. The experimental rotational band dynamic moment of inertia is used to test self-consistent mean-field calculations using the Skyrme SLy4 interaction and a density-dependent pairing force.
15.	Page, R. D., et al. (författare) alpha decay of Re-159 and proton emission from Ta-155 2007 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 75:6, s. 061302- Tidskriftsartikel (refereegranskat)abstract The alpha decay of Re-159 has been observed for the first time in reactions of 300 MeV Ni-58 ions with an isotopically enriched Cd-106 target. The Re-159 ions were separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The alpha decay emanates from the proton-emitting pi h(11/2) state in Re-159 with an energy of E-alpha=6776 +/- 26 keV and a branching ratio of 7.5 +/- 3.5%. This alpha decay populates a state in the closed neutron shell nucleus Ta-155, which decays by emitting 1444 +/- 15 keV protons with a half-life of 2.9(-1.1)(+1.5) ms. These values are consistent with the emission of the proton from a pi h(11/2) orbital. These results fit in with the systematics of proton and alpha-particle separation energies in the region, but disagree with the previously reported decay properties of Ta-155.
16.	Page, R. D., et al. (författare) Probing single-particle structures beyond the proton drip line 2007 Ingår i: Proton Emitting Nuclei and Related Topics. - : American Institute of Physics (AIP). - 9780735404755 ; , s. 137-142 Konferensbidrag (refereegranskat)abstract Single-particle energies have been investigated in the closed neutron shell proton emitter 155Ta. The 155Ta nuclei were populated through the α decay of 159Re, which has been observed for the first time. The 159Re nuclei were produced in reactions of 300 MeV 58Ni ions with an isotopically enriched 106Cd target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The 159Re α decay emanates from the proton-emitting πh11/2 state and populates a state in 155Ta which decays by the emission of a proton from a πh 11/2 orbital. The results fit in with the systematics of proton and α-particle separation energies in the region, but disagree with the previously reported decay properties of 155Ta.
17.	Petrache, C. M., et al. (författare) Evidence of chiral bands in even-even nuclei 2018 Ingår i: Physical Review C. - : American Physical Society. - 2469-9985 .- 2469-9993. ; 97:4 Tidskriftsartikel (refereegranskat)abstract Evidence for chiral doublet bands has been observed for the first time in the even-even nucleus Nd136. One chiral band was firmly established. Four other candidates for chiral bands were also identified, which can contribute to the realization of the multiple pairs of chiral doublet bands (MχD) phenomenon. The observed bands are investigated by the constrained and tilted axis cranking covariant density functional theory (TAC-CDFT). Possible configurations have been explored. The experimental energy spectra, angular momenta, and B(M1)/B(E2) values for the assigned configurations are globally reproduced by TAC-CDFT. Calculated results support the chiral interpretation of the observed bands, which correspond to shapes with maximum triaxiality induced by different multiquasiparticle configurations in Nd136.
18.	Taylor, M. J., et al. (författare) Oblately deformed isomeric proton-emitting state in Lu-151 2015 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 91:4 Tidskriftsartikel (refereegranskat)abstract Gamma rays from excited states feeding a proton-emitting isomeric-state in Lu-151 have been observed for the first time. Comparison with state-of-the-art nonadiabatic quasiparticle calculations indicates an oblately deformed, 3/2(+) proton-emitting state with a quadrupole deformation of beta(2) = -0.11. The calculations suggest an increase in quadrupole deformation, to beta(2) = -0.18, with increasing spin which is understood in terms of the mixing of Nilsson states at the Fermi surface. It is also shown that the proton decay half-life is consistent with that from a 3/2(+) state with a quadrupole deformation of beta(2) = -0.12.
19.	Thomson, J., et al. (författare) Competing quasiparticle configurations in W-163 2010 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 81:1 Tidskriftsartikel (refereegranskat)abstract Excited states in the neutron-deficient nuclide W-163 were investigated using the Cd-106(Ni-60, 2pn)W-163 reaction at a beam energy of 270 MeV. The level scheme for W-163 was extended significantly with the observation of five new band structures. The yrast band based on a 13/2(+) isomeric state is extended up to (57/2(+)). Two band structures were established on the 7/2(-) ground state. Quasiparticle configuration assignments for the new band structures were made on the basis of cranked Woods-Saxon shell-model calculations. The results reported in this article suggest that the negative-parity nu(f(7/2), h(9/2)) orbitals are responsible for the first rotational alignment in the yrast band.
20.	Bäck, Torbjörn, et al. (författare) Lifetime measurement of the first excited 2(+) state in (108)Te 2011 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 84:4, s. 041306- Tidskriftsartikel (refereegranskat)abstract The lifetime of the first excited 2(+) state in the neutron deficient nuclide (108)Te has been measured for the first time, using a combined recoil decay tagging and recoil distance Doppler shift technique. The deduced reduced transition probability is B(E2;0(g.s.)(+) -> 2(+)) = 0.39(-0.04)(+0.05)e(2)b(2). Compared to previous experimental data on neutron deficient tellurium isotopes, the new data point constitutes a large step (six neutrons) toward the N = 50 shell closure. In contrast to what has earlier been reported for the light tin isotopes, our result for tellurium does not show any enhanced transition probability with respect to the theoretical predictions and the tellurium systematics including the new data is successfully reproduced by state-of-the-art shell model calculations.
21.	Cederwall, Bo, et al. (författare) Coexistence in proton rich A-90 and A-170 nuclei. 1998 Ingår i: Abstracts of Papers of the American Chemical Society. - 0065-7727. ; 215, s. U955-U955 Tidskriftsartikel (refereegranskat)
22.	Ghazi Moradi, Farnaz, et al. (författare) High-spin study of 162Ta 2011 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 84:6, s. 064312- Tidskriftsartikel (refereegranskat)abstract Excited states in the odd-odd neutron deficient nucleus (162)Ta (Z = 73, N = 89) have been studied for the first time. The gamma spectroscopy analysis using gamma - gamma - gamma coincidences revealed a strongly coupled rotational structure that was established up to large angular momentum states. The rotational band was assigned to the configuration pi h(11/2)[514]9/2 circle times nu i(13/2)[660]1/2 based on its rotational and electromagnetic properties. The data are interpreted within the framework of total Routhian surface calculations, which suggests an axially symmetric shape with a gamma-softminimum at beta(2) approximate to 0.16 and gamma approximate to 6 degrees. The crossing of the signature partners observed in heavier (N >= 91) odd-odd nuclides in this mass region is found to be absent at N = 89. This might be correlated with a change in S-band structure above the paired band crossing at these neutron numbers.
23.	Gillespie, S. A., et al. (författare) Identification of a 6.6 μ s isomeric state in Ir 175 2019 Ingår i: Physical Review C. - 2469-9985. ; 99:6 Tidskriftsartikel (refereegranskat)abstract An experiment has been performed to study excited states in the neutron-deficient nucleus Ir175 via the use of the JUROGAM II high-purity germanium detector array and the RITU gas-filled separator at JYFL, Jyväskylä. By using isomer tagging, an isomeric state with a half-life of 6.58(15) μs has been observed in Ir175 for the first time. It has been established that the isomer decays via a 45.2 (E1)-26.1 (M1) keV cascade to new states below the previously reported ground state in Ir175 with Iπ=(5/2-). We now reassign this (5/2-) state to the isomeric state discovered in this study.
24.	Gillespie, S. A., et al. (författare) Identification of sub- μ s isomeric states in the odd-odd nucleus Au 178 2021 Ingår i: Physical Review C. - 2469-9985. ; 103:4 Tidskriftsartikel (refereegranskat)abstract The neutron-deficient gold (Z=79) isotopes in the vicinity of the neutron midshell N=104 provide prolific examples of shape coexistence and isomerism at low excitation energy. They can be probed via a number of different experimental techniques. In this study, two new isomeric states with half-lives of 294(7) and 373(9) ns have been observed in the neutron-deficient odd-odd nuclide Au178 (N=99) in an experiment at the RITU gas-filled separator at JYFL, Jyväskylä. This result was achieved due to the use of a segmented planar germanium detector with a high efficiency at low energies. By applying the recoil-decay tagging technique, they were assigned to decay to two different long-lived α-decaying states in Au178.
25.	Grahn, T., et al. (författare) Excited states and reduced transition probabilities in Os-168 2016 Ingår i: PHYSICAL REVIEW C. - : American Physical Society. - 2469-9985. ; 94:4 Tidskriftsartikel (refereegranskat)abstract The level scheme of the neutron-deficient nuclide Os-168 has been extended and mean lifetimes of excited states have been measured by the recoil distance Doppler-shift method using the JUROGAM gamma-ray spectrometer in conjunction with the IKP Koln plunger device. The 168Os. rays were measured in delayed coincidence with recoiling fusion-evaporation residues detected at the focal plane of the RITU gas-filled separator. The ratio of reduced transition probabilities B(E2; 4(1)(+)-> 2(1)(+))/B(E2; 2(1)(+)-> 0(1)(+)) is measured to be 0.34(18), which is very unusual for collective band structures and cannot be reproduced by interacting boson model (IBM-2) calculations based on the SkM* energy-density functional.
26.	Hadinia, Baharak, et al. (författare) First identification of gamma-rays in Te-106 using recoil decay tagging technique 2006 Ingår i: Frontiers in Nuclear Structure Astrophysics, and Reactions: FINUSTAR. - MELVILLE, NY : AMER INST PHYSICS. - 0735403236 - 9780735403239 ; , s. 457-459 Konferensbidrag (refereegranskat)abstract Gamma-ray transitions from excited states in Te-106 have been identified using the recoil decay tagging technique. The experiment which was the reaction Fe-54(Fe-54,2n)Te-106* was performed at the JYFL accelerator facility at the University of Jyvaskyla, Finland. The production cross section was estimated at 25 nb, a new limit for in-beam gamma-ray spectroscopy. A tentative level structure for the ground state band of Te-106 is proposed.
27.	Herzberg, R-D, et al. (författare) Isomer spectroscopy in No-254 2006 Ingår i: Physica Scripta. - 0031-8949 .- 1402-4896. ; T125, s. 73-77 Tidskriftsartikel (refereegranskat)abstract Isomeric states in No-254 were investigated using a calorimetric method. Two different isomers were found with half-lives of T-1/2 = 266 +/- 2 ms and T-1/2 = 184 +/- 3 mu s, respectively. The dominant decay path of the 184 mu s isomer proceeds via states feeding the longer-lived 266 ms isomer. The 266 ms isomer in turn decays via a two-quasi-particle K = 3 band to the ground-state band. The full decay path was observed with the GREAT spectrometer located at the focal plane of the gas-filled separator RITU at the Accelerator Laboratory in Jyvskyl. This work sheds light on the two-quasi-particle structure in this transfermium nucleus.
28.	Hodge, D., et al. (författare) Identification of a dipole band above the Iπ=31/2- isomeric state in Pb 189 2015 Ingår i: Physical Review C. Nuclear Physics. - : American Physical Society. - 0556-2813 .- 1089-490X. ; 92:5 Tidskriftsartikel (refereegranskat)abstract A dipole band of six transitions built upon a firmly established Iπ=31/2- isomeric state has been identified in Pb189 using recoil-isomer tagging. This is the lightest odd-mass Pb nucleus in which a dipole band is known. The dipole nature of the new transitions has been confirmed through angular-intensity arguments. The evolution of the excitation energy and the aligned-angular momentum of the states in the new dipole band are compared with those of dipole bands in heavier, odd-mass lead isotopes. This comparison suggests that the new band in Pb189 is based upon a π[s1/2-2h9/2i13/2]11- - ν[i13/2+-1]13/2+ configuration. However, the increased aligned-angular momentum in Pb189 may suggest evidence for a reduced repulsive proton/neutron-hole interaction compared to dipole bands in the heavier mass isotopes.
29.	Pereira-López, X., et al. (författare) In-beam γ -ray spectroscopy of 94 Ag 2023 Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 59:3 Tidskriftsartikel (refereegranskat)abstract A recoil-beta-tagging experiment has been performed to study the excited T= 0 and T= 1 states in the odd–odd N= Z nucleus 94Ag, populated via the 40Ca(58Ni,1p3n)94Ag reaction. The experiment was conducted using the MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä. Through correlating fast, high-energy beta decays at the MARA focal plane with prompt γ rays emitted at the reaction target, a number of transitions between excited states in 94Ag have been identified. The timing characteristics of these transitions confirm that they fall within decay sequences that feed the short-lived T= 1 ground state of 94Ag. The transitions are proposed to proceed within and between the sets of states with T= 0 and T= 1. Possible correspondence between some of these transitions from analog states in 94Pd has been discussed, and shell-model calculations including multipole and monopole electromagnetic effects have been presented, in order to enable predictions of the decay patterns between the T= 0 and T= 1 states and to allow a theoretical set of Coulomb energy differences to be calculated for the A= 94 T= 1 analog states.
30.	Petrache, C. M., et al. (författare) Collective rotation of an oblate nucleus at very high spin 2019 Ingår i: Physical Review C. - : American Physical Society (APS). - 2469-9985 .- 2469-9993. ; 99:4 Tidskriftsartikel (refereegranskat)abstract A sequence of nine almost equidistant quadrupole transitions is observed in Nd137. The sequence represents an extremely regular rotational band that extends to a spin of about 75/2 and an excitation energy of ≈4.5MeV above yrast. Cranked mean-field calculations of the Nilsson-Strutinsky type suggest an oblate shape for the band. They reproduce the observed I(I+1) dependence of the rotational energy whereas predicting a pronounced decrease in the deformation, which is the hallmark of antimagnetic rotation.
31.	Petri, M., et al. (författare) Nuclear levels in proton-unbound I-109 : Relative single-particle energies beyond the proton drip line 2007 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 76:5 Tidskriftsartikel (refereegranskat)abstract A level scheme has been constructed for the proton-unbound, T-z=3/2 nuclide I-109(53)56 following a recoil-decay-tagging experiment using the Ni-58(Fe-54, p2n gamma) reaction at a beam energy of 195 MeV. The experiment was performed using the highly efficient JUROGAM gamma-ray spectrometer in conjunction with the RITU gas-filled recoil separator and the GREAT focal-plane spectrometer. Cranking calculations are used to interpret band structures built on pi g(7/2) and pi h(11/2) states in a weakly deformed, triaxial nucleus.
32.	Petts, A., et al. (författare) Lifetime measurements and coulomb excitation of light Hg nuclei 2009 Ingår i: Capture Gamma-Ray Spectroscopy and Related Topics. - : American Institute of Physics (AIP). - 9780735406230 ; , s. 414-418 Konferensbidrag (refereegranskat)abstract Two complementary experimental programs have taken place to investigate the origin and evolution of shape coexistence in the light mercury region. Recoil Distance Doppler-shift measurements were performed at the University of Jyväskylä utilizing the Köln plunger device in conjunction with the JUROGAM + RITU + GREAT setup. In addition, Coulomb excitation measurements of 184,186,188Hg were performed at REX-ISOLDE using the MINIBALL Ge-detector array. The results of the lifetime measurements of the yrast states up to Iπ = 10+ in 182Hg are reported. Preliminary analysis of the Coulomb excitation data is also discussed.
33.	Saygi, B., et al. (författare) Reduced transition probabilities along the yrast line in W-166 2017 Ingår i: Physical Review C. - : American Physical Society. - 2469-9985 .- 2469-9993. ; 96:2 Tidskriftsartikel (refereegranskat)abstract Lifetimes of excited states in the yrast band of the neutron-deficient nuclide W-166 have been measured utilizing the DPUNS plunger device at the target position of the JUROGAM II gamma-ray spectrometer in conjunction with the RITU gas-filled separator and the GREAT focal-plane spectrometer. Excited states in W-166 were populated in the Mo-92(Kr-78, 4p) reaction at a bombarding energy of 380 MeV. The measurements reveal a low value for the ratio of reduced transitions probabilities for the lowest-lying transitions B(E2; 4(+)-> 2(+)) / B(E2; 2(+)-> 0(+)) = 0.33(5), compared with the expected ratio for an axially deformed rotor (B-4/2 = 1.43).
34.	Zhang, W., et al. (författare) Decay spectroscopy of 171,172Os and 171,172,174Ir 2023 Ingår i: Physical Review C. - : American Physical Society (APS). - 2469-9985 .- 2469-9993. ; 107:1 Tidskriftsartikel (refereegranskat)abstract We report on a study of the α-decay fine structure and the associated Eα−Eγ correlations in the decays of 171,172Os and 171,172,174Ir. In total, 13 new α-decay energy lines have been resolved, and three new γ-ray transitions have been observed following the new decay branches to 168Re and 167W. The weak α-decay branch from the bandhead of the νi13/2 band in 171Os observed in this work highlights an unusual competition between α, β, and electromagnetic decays from this isomeric state. The nucleus 171Os is therefore one of few nuclei observed to exhibit three different decay modes from the same excited state. The nuclei of interest were produced in 92Mo(83Kr,xpyn) fusion-evaporation reactions at the Accelerator Laboratory of the University of Jyväskylä, Finland. The fusion products were selected using the gas-filled ion separator RITU and their decays were characterized using an array of detectors for charged particles and electromagnetic radiation known as GREAT. Prompt γ-ray transitions were detected and correlated with the decays using the JUROGAM II germanium detector array surrounding the target position. Results obtained from total Routhian surface (TRS) calculations suggest that α-decay fine structure and the associated hindrance factors may be a sensitive probe of even relatively small shape changes between the final states in the daughter nucleus.
35.	Ahlgren Cederlöf, Ebba, et al. (författare) Lifetime measurement of the yrast 2+ state in 118Te 2023 Ingår i: European Physical Journal A. - : Springer. - 1434-6001 .- 1434-601X. ; 59:12 Tidskriftsartikel (refereegranskat)abstract The electromagnetic transition probabilities of the yrast 2+ states in the midshell Te isotopes, two protons above the closed shell at Sn, are of great importance for the understanding of nuclear collectivity in these isotopes and the role played by the neutron-proton interactions and cross-shell excitations. However, the large uncertainty of the experimental data for the midshell nucleus 118Te and the missing data for 116Te make it difficult to pin down the general trend of the evolution of transition probabilities as a function of the neutron number. In this work, the lifetime of the yrast 2+ state in 118Te was measured, with the aim of reducing the uncertainty of the previous measurement. The result is τ2+ = 7.46(19) ps. In addition, the lifetime of the 4+ state was measured to be τ4+ = 4.25(23) ps. The experimental transition rates are extracted from the measured lifetimes and compared with systematic large-scale shell-model calculations. The trend of the B(E2; 0+ → 2+) values in the midshell area is in good agreement with the calculations and the calculated B4/2 ratio provide evidence for 118Te as a near perfect harmonic vibrator.
36.	Bark, R A, et al. (författare) Bandcrossings in Os-171 1999 Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 646:4, s. 399-413 Tidskriftsartikel (refereegranskat)abstract The nucleus Os-171 has been populated using the reaction Sn-116(Ni-58,2pn). Four new bands are identified, and the previously known bands are extended in spin, to a maximum of 53/2 (h) over bar. One- and three-quasiparticle configurations are identified, and beta, gamma, and octupole configurations are assigned tentatively. The effects of a possible intruder configuration on the negative parity bands are tested using band-mixing calculations.
37.	Bark, R A, et al. (författare) Coexistence of triaxial and prolate shapes in Ir-171 1999 Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 657:2, s. 113-133 Tidskriftsartikel (refereegranskat)abstract Excited states in Ir-171 have been observed for the first time. Gamma-rays were assigned to the nucleus by the recoil-decay tagging method, The ground-state band has a structure consistent with an h(11/2) proton coupled to a core of large triaxial deformation. At high spins, a bandcrossing occurs which is interpreted as a change in shape to a prolate deformation, Band-mixing calculations are performed for Ir171-175. These show that shape-coexistence between triaxial and prolate states in these nuclei follows the same systematics found in their Pt and Os neighbours. The systematics are also compared with deformations calculated for Ir171-179 using the code "Ultimate Cranker". Dipole bands were also observed, but tilted axis cranking calculations suggest that they are associated with a collective rotation.
38.	CEDERKALL, J, et al. (författare) 1ST OBSERVATION OF EXCITED-STATES IN SB-108 1995 Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 581:1, s. 189-204 Tidskriftsartikel (refereegranskat)abstract A spectroscopic study of Sb-108 has been carried out as a part of a larger experiment where in total twenty-nine different residual nuclei were identified. This study gives the first information on excited levels in this nucleus. A low-lying two-quasi-particle multiplet together with some of the higher lying levels are discussed within the framework of the nuclear shell model. A rotational, strongly coupled, band is identified as, most likely, being built on the deformed pig9/2(-1) nuh11/2 configuration in accordance with total routhian surface calculations. Tentative spins and parities are presented as well as B(M1)/B(E2) ratios for some of the transitions in the strongly coupled band.
39.	CEDERKALL, J, et al. (författare) 1ST OBSERVATION OF EXCITED-STATES IN SB-108 1995 Ingår i: NUCLEAR PHYSICS A. ; 581:1 Annan publikation (övrigt vetenskapligt/konstnärligt)
40.	Cederwall, Bo, et al. (författare) Collective rotational-vibrational transition in the very neutron-deficient nuclei (171,172)-Pt 1998 Ingår i: Physics Letters B. - AMSTERDAM, NETHERLANDS : ELSEVIER SCIENCE. - 0370-2693 .- 1873-2445. ; 443:1-4, s. 69-76 Tidskriftsartikel (refereegranskat)abstract Excited states have been identified for the first time in very neutron deficient Pt-171.172 nuclei using the recoil-or-decay tagging technique. The ground-state band in Pt-172 has been established up to I-pi = 8+. A similar level sequence, presumably built on the I-pi = 13/2(+) state, is observed for Pt-171. The data are compared with theoretical calculations based on the mean field approach and the random phase approximation and are put into the context of the systematics of platinum isotopes. (C) 1998 Elsevier Science B.V. All rights reserved.
41.	DOMBRADI, Z, et al. (författare) HIGH-SPIN SPECTROSCOPY OF TE-109 1995 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 51:5, s. 2394-2399 Tidskriftsartikel (refereegranskat)
42.	DOMBRADI, Z, et al. (författare) IDENTIFICATION AND SPECTROSCOPY OF THE TE-108 NUCLEUS 1994 Ingår i: Zeitschrift für Physik A Hadrons and Nuclei. - 0939-7922 .- 1431-5831. ; 350:1, s. 3-4 Tidskriftsartikel (refereegranskat)abstract Excited states of Te-108 were populated in the Fe-54 + Ni-58 (270 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction channel separation. Gamma rays belonging to the neutron deficient nucleus Te-108 were identified for the first time. On the basis of gammagamma-coincidence and angular correlation relations a level scheme was constructed with tentative spin and parity assignments. The structure of the nucleus is discussed in the framework of systematics of heavier Te nuclei.
43.	Doncel, Maria, et al. (författare) Lifetime measurements of excited states in W-162 and W-164 and the evolution of collectivity in rare-earth nuclei 2017 Ingår i: Physical Review C. - : American Physical Society. - 2469-9985 .- 2469-9993. ; 95:4 Tidskriftsartikel (refereegranskat)abstract Lifetimes of the first excited 2(+) states in the extremely neutron- deficient W-162 and W-164 nuclei have been measured using the recoil distance Doppler shift technique. Experimental B(E2) data for the isotopic chains of hafnium, tungsten, and osmium, from the midshell region near the beta-stability line towards the N = 82 closed shell and the most neutron-deficient nuclides, are compared with predictions of nuclear deformations and 2(1)(+) -> 0(g.s)(.+) reduced transition strengths from different classes of state-of-the-art theoretical model calculations. The results reveal striking differences and deficiencies in the predictive power of current nuclear structure models.
44.	Drummond, M. C., et al. (författare) Low-lying excited states in the neutron-deficient isotopes Os-163 and Os-165 2013 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 87:5, s. 054309- Tidskriftsartikel (refereegranskat)abstract Excited states in the neutron-deficient isotopes Os-163 and Os-165 were identified using the JUROGAM and GREAT spectrometers in conjunction with the RITU gas-filled separator. The Os-163 and Os-165 nuclei were populated via the Cd-106(Ni-60,3n) and Mo-92(Kr-78,2p3n) reactions at bombarding energies of 270 MeV and 357 MeV, respectively. Gamma-ray emissions from these nuclei have been established unambiguously using the recoil-decay tagging technique and a coincidence analysis has allowed level schemes to be established. These results suggest that the yrast states are based upon negative-parity configurations originating from the f(7/2) and h(9/2) orbitals.
45.	FAHLANDER, C, et al. (författare) IN-BEAM SPECTROSCOPY OF TE-110 1994 Ingår i: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 577:3-4, s. 773-785 Tidskriftsartikel (refereegranskat)abstract The neutron-deficient nucleus Te-110 has been investigated by in-beam spectroscopic methods using the NORDBALL multi-detector array. Except for the energy of one level observed in alpha-decay, excited states in Te-110 were previously unknown. The level scheme constructed from gamma gamma-coincidence relationships is presented with tentative spin assignments up to I-pi = 21(-). Above spin 8(+) the yrast states have negative parity. They are most likely the members of a band predominantly based on the nu(h(11/2)g(7/2)) two-quasiparticle configuration. A band crossing is observed at I-pi approximate to 17(-). It is suggested to be caused by the alignment of two h(11/2) neutrons. The cranked shell model correctly predicts the spin alignment, but fails to reproduce the observed band crossing frequency, possibly because of octupole effects.
46.	Grahn, T., et al. (författare) Collectivity and configuration mixing in Pb186,188 and Po194 2006 Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:6 Tidskriftsartikel (refereegranskat)abstract Lifetimes of prolate intruder states in Pb186 and oblate intruder states in Po194 have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift lifetime measurements. In addition, lifetime measurements of prolate states in Pb188 up to the 8+ state were carried out using the recoil-gating method. The B(E2) values have been deduced from which deformation parameters \|β2\|=0.29(5) and \|β2\|=0.17(3) for the prolate and the oblate bands, respectively, have been extracted. The results also shed new light on the mixing between different shapes.
47.	Herzáň, A., et al. (författare) Detailed spectroscopy of Bi 193 2015 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 92:4 Tidskriftsartikel (refereegranskat)abstract An experiment aiming to study shape coexistence in Bi193 has been performed. Due to its transitional character, it has an exceptionally large number of structures identified close to the yrast line. Many new states have been found, significantly extending the previously known level scheme of Bi193, including several new rotational bands. The πi13/2 band was extended to Iπ=45/2+. The Iπ=31/2+ member of the πi13/2 band was found to de-excite also to a long-lived isomeric state. This isomeric state is located at 2350 keV and has a spin and parity of 29/2+. The half-life of the isomeric state was measured to be 85(3) μs and it decays via the emission of an 84 keV E2 transition. A level structure feeding this isomeric state was constructed. A low-energy, 49 keV transition has been identified to depopulate the (29/2-) isomeric state, which places it at an energy 2405 keV in the level scheme. This is the first time such a decay has been observed in the neutron-deficient Bi isotopes. A superdeformed band almost identical to that present in the neighboring isotope Bi191, based on the 1/2[651] Nilsson orbital, has also been identified.
48.	Herzan, A., et al. (författare) Detailed spectroscopy of Bi-195 2017 Ingår i: Physical Review C. - : American Physical Society. - 2469-9985 .- 2469-9993. ; 96:1 Tidskriftsartikel (refereegranskat)abstract An experiment focused on the study of shape coexistence and new high-spin structures in Bi-195 has been performed. The nucleus is in a transitional region of the bismuth isotope chain. A large number of new states have been found, resulting in a significant extension of the previously known level scheme. Several new collective structures have been identified. A strongly coupled rotational band built upon the 13/2(+) isomeric state was extended up to I-pi = (49/2(+)) and an energy of 5706 keV. The I-pi = 31/2(+) member of the pi i(13/2) band was also found to feed a new long-lived isomeric state with an excitation energy of 2616 keV and a spin and parity of I-pi = 29/2(+). The half-life of the 29/2+ isomeric state was determined to be 1.49(1) mu s. It decays via the emission of 457-keV E2 and 236-keV E1 transitions, respectively. A low-energy 46-keV E2 transition has been identified to depopulate the (29/(2-)) isomeric state, with a measured half-life of T-1/2 = 614(5) ns. This transition allows the excitation energy of the isomeric state to be determined as 2381 keV. The feeding patterns of both 29/2(+) and (29/2(-)) isomeric states have also been described. This is the first time collective structures have also been observed up to high spins and excitation energies in the neutron-deficient Bi-195 nucleus. Evidence for the manifestation of shape coexistence in Bi-195 is also discussed.
49.	Hornillos, M. B. G., et al. (författare) gamma-ray spectroscopy approaching the limits of existence of atomic nuclei : A study of the excited states of Pt-168 and Pt-169 2009 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 79:6 Tidskriftsartikel (refereegranskat)abstract Excited states in the N=90 and N=91 Pt nuclei have been investigated using the JUROGAM and GREAT spectrometers in conjunction with the RITU gas-filled separator. These nuclei were populated via the reactions Mo-92(Kr-78,2n) and Mo-94(Kr-78,3n) at 335 and 348 MeV, respectively. The recoil-decay tagging technique has been used to correlate prompt gamma radiation with the characteristic alpha decays of Pt-168 and Pt-169. A gamma-gamma analysis has allowed a level scheme for Pt-168 to be reported for the first time and the level scheme for Pt-169 to be extended. The excitation energies of the proposed positive-parity yrast states of Pt-168 are compared with calculations based on the interacting boson model and found to be in excellent agreement. These data show a continuation of the trend toward vibrational nuclei as the N=82 shell gap is approached. In addition, new excited states constituting two decay paths have been discovered in Pt-169. .
50.	Ideguchi, E., et al. (författare) High-spin intruder band in In-107 2010 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 81:3, s. 034303- Tidskriftsartikel (refereegranskat)abstract High-spin states in the neutron-deficient nucleus In-107 were studied via the Ni-58(Cr-52,3p) reaction. In-beam gamma rays were measured using the JUROGAM detector array. A rotational cascade consisting of ten gamma-ray transitions, which decays to the 19/2(+) level at 2.002 MeV, was observed. The band exhibits the features typical for smooth terminating bands that also appear in rotational bands of heavier nuclei in the A similar to 100 region. The results are compared with total Routhian surface and cranked Nilsson-Strutinsky calculations.

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