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Currently, forty-one cesium, thirty-five lanthanum, thirty-two praseodymium, and thirty-one promethium isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.
Evaluated nuclear structure and decay data for all nuclei within the A=133 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by S. Raab (1995Ra12), published in Nuclear Data Sheets75, 491 (1995).
Promethium isotope heated ammonia microthrustor using heat shield package to maintain temperature
The six-level sequence deduced for the odd-odd nucleus {sup 156}Pm in the high-spin studies following spontaneous fission of {sup 252}Cf is shown to constitute the K{sup {pi}=}4{sup +} yrast band having the two-quasiparticle configuration {l_brace}p:5/2[532]+ n:3/2[521]{r_brace}. Spin parities I{sup {pi}=}4{sup +} through 9{sup +} are assigned to the earlier suggested six levels. The location and the decay {gamma}'s of the 10{sup +} level of this band are indicated. It is also pointed out that there are no {gamma} rays common to these postfission high-spin spectra and those seen in the {sup 156}Nd {beta}-decay studies.
The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{beta}{beta}) of {sup 150}Nd. The present results thus provide useful information on the neutrino responses for evaluating the 0{nu}{beta}{beta} and 2{nu}{beta}{beta} matrix elements. The 2{nu}{beta}{beta} matrix element calculated from the Gamow-Teller transitions through the lowest 1{sup +} state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2{nu}{beta}{beta} direct counting experiments, and at least several transitions through 1{sup +} intermediate states in {sup 150}Pm are required to explain the 2{nu}{beta}{beta} half-life. Because Gamow-Teller transitions in the {sup 150}Sm(t,{sup 3}He) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2({h_bar}/2{pi}){omega}, {Delta}L=0, {Delta}S=1 isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.
The high-spin states of {sup 141}Pm have been investigated through the reaction {sup 126}Te({sup 19}F,4n) at a beam energy of 90 MeV. A previous level scheme has been updated with spins up to 49/2({h_bar}/2{pi}). Six collective bands at high spins are newly observed. Based on the systematic comparison, one band is proposed as a decoupled band; two bands with strong {Delta}I=1 M1 transitions inside the bands are suggested as the oblate bands with {gamma} {approx}-60 deg.; three other bands with large signature splitting have been proposed with the oblate-triaxial deformation with {gamma}{approx} -90 deg. The triaxial n-particle-n-hole particle rotor model calculations for one of the oblate bands in {sup 141}Pm are in good agreement with the experimental data. The other characteristics for these bands have been discussed.
Radioimmunotherapy utilize a targeting antibody coupled to a therapeutic isotope to target and treat a tumor or disease. In this study we examine the synthesis and cell binding of a polymer scaffold containing a radiotherapeutic isotope and a targeting antibody. Methods: The multistep synthesis of a fluorescent or 149 Promethium-labeled Trastuzumab-polyethyleneimine (PEI), Trastuzumab, or PEI is described. In vitro uptake, internalization and/or the binding affinity to the Her2/neu expressing human breast adenocarcinoma SKBr3 cells was investigated with the labeled compounds. Fluorescent-labeled Trastuzumab-PEI was internalized more into cells at 2 and 18 h than fluorescent-labeled Trastuzumab or PEI. The fluorescent-labeled Trastuzumab was concentrated on the cell surface at 2 and 18 h and the labeled PEI had minimal uptake. DOTA-PEI was prepared and contained an average of 16 chelates per PEI; the compound was radio-labeled with 149 Promethium and conjugated to Trastuzumab. The purified 149 Pm-DOTA-PEI-Trastuzumab had a radiochemical purity of 96.7% and a specific activity of 0.118 TBq/g. The compound demonstrated a dissociation constant for the Her2/neu receptor of 20.30 ± 6.91 nM. In conclusion, the results indicate the DOTA-PEI-Trastuzumab compound has potential as a targeted therapeutic carrier, and future in vivo studies should be performed.
We introduce the application of an automated online separation–direct analysis method, RAPID (Rapid Analysis of Post-Irradiation Debris), for the simultaneous measurement of both radioactive and stable fission isotopes from an irradiated highly-enriched uranium target. Developed for the measurement of the concentration and isotopic composition of over 40 elements down to the femtogram level, the RAPID method possesses the sensitivity, stability, and precision needed to achieve accurate, low-level analyses of elements of non-natural origin. The isotopic compositions and concentrations of key fission elements cesium, strontium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, and samarium have been measured repeatedly over a six-week period. The validity of these measurements was confirmed using ORIGEN (Oak Ridge Isotope GENeration), an isotope depletion and decay modeling software, to within 1–3%.
In this paper, we describe the 147 Pm production yields and level of impurities from several targets that consisted of milligram quantities of highly enriched 146 Nd oxide irradiated at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory for durations ranging from 24 to180 h. A comparison between theoretical and experimental data are also presented, and attempts were made to empirically evaluate the neutron capture cross-sections of 41.3-d 148m Pm and 5.4-d 148g Pm. For a one-cycle irradiation (~24 days), 147 Pm yield reaches a maximum value of 101.8 MBq/mg (2.75 mCi/mg) at 60 days after the end of bombardment. Because of large neutron capture cross-sections of 147 Pm, the yield of 147 Pm does not significantly increase with longer irradiation. Our estimates of the thermal neutron capture cross-section and resonance integral for 146 Nd at 1.48 ± 0.05 b and 2.56 ± 0.25 b, respectively, were consistent with the reported values. The effective neutron capture cross-section of 147 Pm to 148m Pm was 53.3 ± 2.7 b - a factor of 2 lower than the 98.7 ± 6.5 b calculated from reported cross-sections. The measured σ eff to the ground state (5.37-d 148g Pm) was 82.0 ± 4.1 b; ~34 % lower than the value of 139 ± 0 b calculated from reported cross-sections. In this work, we also describe the development of a chemical process based on extraction and ion-exchange chromatography for separation of 147 Pm from milligram quantities of 146 Nd and other impurities. Sequential separation of Pm from the Nd target and from other radioisotopic impurities ( 153 Gd and 154&155 Eu, 192 Ir, and 60 Co) was achieved using a LN extraction resin in HCl media followed by further purification of Pm from 60 Co and 192 Ir using a low cross-linking cation exchange resin. Based on these data, we estimated that two rounds of purification under our experimental conditions can provide a mass separation factor of > 104 between Pm and Nd. Our data indicate that curie quantities of 147 Pm with suitable chemical and radioisotopic purity for applications in beta voltaic batteries can be produced by irradiating gram quantities of highly enriched 146 Nd in the flux trap of HFIR for one cycle.
The chromatographic resins DGA and LN have been used sequentially to separate curium, californium, plutonium, and various fission products (FPs) to obtain products with a pure radioisotope or a radioelement with high isotopic purity. This 2-step combination of resins has found applications in the 252 Cf and 238 Pu campaigns performed at Oak Ridge National Laboratory. Experiments have been carried out in glove boxes, shielded caves, and hot cells, demonstrating that these resins are adequate and maintain their performance in highly radiolytic environments. We find that using these resins has led to the recovery of curium highly enriched (>95%) in 248 Cm, the clean separation of 251 Cf for the superheavy element research, and the recovery of 147 Pm from the FP stream obtained during the 238 Pu production campaign while demonstrating that the raffinate post DGA is essentially free of transuranic elements.
The Savannah River Site (SRS) processes used-nuclear fuel to recover uranium. There are many interesting fission products lost in the raffinate from this separation including 147 Pm. Here, the goal of this work was to recover 147 Pm from SRS waste solutions. A radiochemical separation method typically used for the determination of 147 Pm and 151 Sm was modified to purify significant quantities of 147 Pm from the H Canyon waste solutions. The developed scheme was tested on a small aliquot of waste solution from the processing of used fuel from the High Flux Isotope Reactor at Oak Ridge National Laboratory.
The possibility of using elemental Tc (Z = 43) and Pm (Z = 61) as clocks to measure the mean cosmic-ray confinement time in the Galaxy, tau(epsilon) is considered. For this purpose it is necessary to estimate the unknown beta(+) decay half-lives of several Tc and Pm isotopes; these estimates are obtained using beta-decay systematics. In the case of Tc it is possible to estimate the half-lives sufficiently well and show that this element can indeed be used as a cosmic-ray clock; in the case of Pm the half-lives are too uncertain to permit any conclusion. In order to make meaningful measurement of tau(epsilon) using elemental Tc, a comsic-ray detector must have a charge resolution less than about 0.25e in the region around Tc, and enough collecting power to detect a few hundred Tc nuclei.