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Multicentre clinical trials involving a dosimetry component are becoming more prevalent in molecular radiotherapy and are essential to generate the evidence to support individualised approaches to treatment planning and to ensure that sufficient patients are recruited to achieve the statistical significance required. Quality assurance programmes should be considered to support the standardisation required to achieve meaningful results. Trials should be designed to ensure that dosimetry results from image acquisition systems across centres are comparable by incorporating steps to standardise the methodologies used for the quantification of images and dosimetry. Furthermore, it is essential to assess the expertise and resources available at each participating site prior to trial commencement. A quality assurance plan should be drawn up and training provided if necessary. Standardisation of quantification and dosimetry methodologies used in a trial are essential to ensure that results from different centres may be collated. In addition, appropriate uncertainty analysis should be carried out to correct for differences in methodologies between centres. Recommendations are provided to support dosimetry studies based on the experience of several previous and ongoing multicentre trials. • Multicentre clinical trials involving a dosimetry component are becoming more prevalent in molecular radiotherapy. • Recommendations are provided to support molecular radiotherapy dosimetry studies based on experience of previous/ongoing multicentre trials. • In the future, the use of global calibration factors will potentially allow for expansion of existing imaging networks. [ABSTRACT FROM AUTHOR]

The β decay of 129Cd, produced in the relativistic fission of a 238U beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the γ radiation emitted after the β decays, a level scheme of l29In was established comprising 31 excited states and 69 γ-ray transitions. The experimentally determined level energies are compared to state-of-the-art shell-model calculations. The half-lives of the two γ-decaying states in 129Cd were deduced and the β feeding to excited states in 129In were analyzed. It is found that, as in most cases in the Z < 50, N ≤ 82 region, both decays are dominated by the v0g7/2 -> πOg9/2 Gamow-Teller transition, although the contribution of first-forbidden transitions cannot be neglected. [ABSTRACT FROM AUTHOR]

The decay of an isomeric state in the neutron-rich nucleus 129 Cd has been observed via the detection of internal conversion and Compton electrons providing first experimental information on excited states in this nucleus. The isomer was populated in the projectile fission of a 238 U beam at the Radioactive Isotope Beam Factory at RIKEN. From the measured yields of γ -rays and internal conversion electrons, a multipolarity of E 3 was tentatively assigned to the isomeric transition. A half-life of T 1 / 2 = 3.6 ( 2 ) ms was determined for the new state which was assigned a spin of ( 21 / 2 + ) , based on a comparison to shell model calculations performed using state-of-the-art realistic effective interactions. [ABSTRACT FROM AUTHOR]

Reduced transition strengths of the deexciting transitions from the first two excited states in 33Ar were measured in a relativistic Coulomb excitation experiment at the GSI Helmholtz center. The radioactive ion beam was produced by fragmentation of a primary 36Ar beam on a 9Be target followed by the selection of the reaction product of interest via the GSI Fragment Separator. The 33Ar beam hit a secondary 197Au target with an energy of approximately 145 MeV/nucleon. An array of high-purity germanium cluster detectors and large-volume BaF2 scintillator detectors were employed for γ-ray spectroscopy at the secondary target position. The Lund-York-Cologne Calorimeter was used to track the outgoing ions and to identify the nuclear reaction channels. For the two lowest energy excited states of 33Ar the reduced transition strengths have been determined. With these first results the Tz = -3/2 nucleus 33Ar is now, together with 21Na (Tz = -1/2), the only neutron-deficient odd-A sd shell nucleus in which experimental transition strengths are available. The experimental values are compared to results of shell-model calculations which describe simultaneously mirror-energy differences and transition-strength values of mirror pairs in the sd shell in a consistent way. [ABSTRACT FROM AUTHOR]

A low-lying state in In82131, the one-proton hole nucleus with respect to double magic Sn132, was observed by its γ decay to the Iπ=1/2– β-emitting isomer. We identify the new state at an excitation energy of Ex=1353  keV, which was populated both in the β decay of 131Cd83 and after β-delayed neutron emission from 131Cd84, as the previously unknown πp3/2 single-hole state with respect to the 132Sn core. Exploiting this crucial new experimental information, shell-model calculations were performed to study the structure of experimentally inaccessible N=82 isotones below 132Sn. The results evidence a surprising absence of proton subshell closures along the chain of N=82 isotones. The consequences of this finding for the evolution of the N=82 shell gap along the r-process path are discussed. [ABSTRACT FROM AUTHOR]

Several experiments were conducted at the 10 MV Van-de-Graaff tandem accelerator at the Institute of Nuclear Physics, Cologne, to detect proton emission from the isomeric 6457-keV 10 + state in 54 Ni . Excitation functions for two fusion–evaporation reactions were measured to maximise the population of the rare two-neutron evaporation channel from a 56 Ni compound nucleus. The search for delayed proton emission was based on the 28 Si ( 28 Si , 2 n ) 54 Ni reaction at a beam energy of 70 MeV. For this reaction, a cross-section limit for the population of the 10 + state in 54 Ni and its proton-decay branch was determined to be σ < 22 nb. [ABSTRACT FROM AUTHOR]

The neutron-rich isotopes of palladium have attracted considerable interest in terms of the evolution of the N = 82 neutron shell closure and its influence on the r -process nucleosynthesis. In this Letter, we present the first spectroscopic information on the excited states in 125Pd 79 and 127Pd 81 studied using the EURICA γ -ray spectrometer, following production via in-flight fission of a high-intensity 238U beam at the RIBF facility. New isomeric states with half-lives of 144(4) ns and 39(6) μs have been assigned spins and parities of (23 / 2 +) and (19 / 2 +) in 125Pd and 127Pd, respectively. The observed level properties are compared to a shell-model calculation, suggesting the competition between proton excitations and neutron excitations in the proton-hole and neutron-hole systems in the vicinity of the doubly magic nucleus 132Sn. [ABSTRACT FROM AUTHOR]

A new high-spin isomer in the neutron-rich nucleus 128 Cd was populated in the projectile fission of a 238 U beam at the Radioactive Isotope Beam Factory at RIKEN. A half-life of T 1 / 2 = 6.3 ( 8 ) ms was measured for the new state which was tentatively assigned a spin/parity of ( 15 − ). The experimental results are compared to shell model calculations performed using state-of-the-art realistic effective interactions and to the neighbouring nucleus 129 Cd. In the present experiment no evidence was found for the decay of a 18 + E 6 spin-trap isomer, based on the complete alignment of the two-neutron and two-proton holes in the 0 h 11 / 2 and the 0 g 9 / 2 orbit, respectively, which is predicted to exist by the shell model. [ABSTRACT FROM AUTHOR]

In the EURICA campaign aimed at exploration of the 78Ni region, an isomeric state of 76Co has been observed via γ-ray spectroscopy. The nuclei were produced by in-flight fission of a 238U beam at the Radioactive Isotope-Beam Factory. Two coincident γ rays of 192.02(30) and 446.4(7) keV from the decay of a t 1/2 = 2.96(29/25) μs isomeric state of 76Co have been observed. The decay of the isomer was assigned to an E1 transition with a reduced transition probability of B (E1;3+ → 2-) = 1.79(16) x 10-8 W.u. A, β-decaying state with spin-parity 1- and a half-life of 16(4) ms was also observed in the data, and the known state with a half-life of 22g) ms was assigned to have a spin-parity of 8-. Furthermore, the isomer of 76Ni has been remeasured to 547.8(33) ns giving a B(E2; 8+→ 6+) value of 0.786(5) W.u. A new excited state at 2994.6(5) keV, decaying via a y ray of 2004.5(4) keV, has also been observed. This is in agreement with either of the predicted 0+2 or 2+2 states. These results are discussed in terms of the shell model and the interaction of the vp1½ and π f 7/2 orbitals. [ABSTRACT FROM AUTHOR]

The β-decay half-lives of 110 neutron-rich isotopes of the elements from Rb37 to Sn50 were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events. [ABSTRACT FROM AUTHOR]

Delayed γ-ray cascades, originating from the decay of (6+) isomeric states, in the very neutron-rich, semimagic isotopes 136,138Sn have been observed following the projectile fission of a 238U beam at RIBF, RIKEN. The wave functions of these isomeric states are proposed to be predominantly a fully aligned pair of f7/2 neutrons. Shell-model calculations, performed using a realistic effective interaction, reproduce well the energies of the excited states of these nuclei and the measured transition rates, with the exception of the B(E2;6+→4+) rate of 136Sn, which deviates from a simple seniority scheme. Empirically reducing the υf27/2 orbit matrix elements produces a 4+1 state with almost equal seniority 2 and 4 components, correctly reproducing the experimental B(E2;6+→4+) rate of 136Sn. These data provide a key benchmark for shell-model interactions far from stability. [ABSTRACT FROM AUTHOR]

A new isomer with a half-life of 23.0(8) ms has been identified at 2406 keV in 126Pd and is proposed to have a spin and parity of 10+ with a maximally aligned configuration comprising two neutron holes in the 1h11/2 orbit. In addition to an internal-decay branch through a hindered electric octupole transition, β decay from the long-lived isomer was observed to populate excited states at high spins in 126Ag. The smaller energy difference between the 10+ and 7- isomers in 126Pd than in the heavier N=80 isotones can be interpreted as being ascribed to the monopole shift of the 1h11/2 neutron orbit. The effects of the monopole interaction on the evolution of single-neutron energies below 132Sn are discussed in terms of the central and tensor forces. [ABSTRACT FROM AUTHOR]

The half-lives of 20 neutron-rich nuclei with Z = 27-30 have been measured at the RIBF, including five new half-lives of 76Co(21.7+6.5 -4.9 ms), 77Co(13.0++7.2 -4.3 ms), 79Ni(43.0+8.6 -7.5 ms), 80Ni(23.9++26.0 -17.2 ms), and 81Cu(73.2 ± 6.8 ms). In addition, the half-lives of 73-75Co, 74-78Ni, 78-80Cu, and 80-82Zn were determined with higher precision than previous works. Based on these new results, a systematic study of the β-decay half-lives has been carried out, which suggests a sizable magicity for both the proton number Z = 28 and the neutron number N = 50 in 78Ni. [ABSTRACT FROM AUTHOR]

Abstract: The concept, design and prototype developments for the Lund–York–Cologne CAlorimeter (LYCCA) is presented. LYCCA is a modular device for the NUclear STructure, Astrophysics and Reactions (NUSTAR) science pillar of the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, Germany. LYCCA is designed to discriminate heavy ions produced in nuclear reactions induced by relativistic radioactive ion beams. Measurements of energy loss, total energy, and time-of-flight allow the derivation of proton number, Z, and mass number, A, of the reaction products. LYCCA-inherent tracking of the flight paths of the reaction products enables coincident HIgh-resolution in-beam -ray SPECtroscopy (HISPEC) of atomic nuclei far from the line of -stability. [Copyright &y& Elsevier]

116Ru and 118Ru have been studied via β-delayed y-ray spectroscopy of nuclei produced in fragmentation reactions at the Radioactive Ion-Beam Factory (RIBF) facility. Level schemes with positive-parity states up to spin 7=6 have been constructed. The results have been discussed in terms of the interacting boson model, the algebraic collective model, and total Routhian surfaces. We conclude that the very neutron-rich nuclei still show many features associated with triaxial y-soft nuclei, represented by the 0(6) symmetry, but are approaching a spherical structure, the U(5) symmetry, with increasing neutron number towards the N = 82 shell closure. In 118Ru, hints of a shape transition in the ground state have been observed. [ABSTRACT FROM AUTHOR]

The change of the shell structure in atomic nuclei, so-called " nuclear shell evolution ", occurs due to changes of major configurations through particle-hole excitations inside one nucleus, as well as due to variation of the number of constituent protons or neutrons. We have investigated how the shell evolution affects Gamow-Teller (GT) transitions that dominate the β decay in the region below 132Sn using the newly obtained experimental data on a long-lived isomer in 127Ag. The T 1 / 2 = 67.5 (9) ms isomer has been identified with a spin and parity of (27 / 2 +) at an excitation energy of 1942 − 20 + 14 keV, and found to decay via an internal transition of an E 3 character, which competes with the dominant β -decay branches towards the high-spin states in 127Cd. The underlying mechanism of a strong GT transition from the 127Ag isomer is discussed in terms of configuration-dependent optimization of the effective single-particle energies in the framework of a shell-model approach. [ABSTRACT FROM AUTHOR]

The β decay of the semi-magic nucleus 130Cd has been studied at the RIBF facility at the RIKEN Nishina Center. The high statistics of the present experiment allowed for a revision of the established level scheme of 130In and the observation of additional β feeding to high-lying core-excited states in 130In. The experimental results are compared to shell-model calculations employing a model space consisting of the full major N=50-82 neutron and Z=28-50 proton shells and the NA-14 interaction, and good agreement is found. [ABSTRACT FROM AUTHOR]