Ho Isotopes Research Articles

Hydrochemical and Stable Isotope characteristics of surface water and groundwater in Xiliugou and Wulagai River basin, North China

The investigation of the correlation between groundwater and surface water in terms of water origin and transformation is crucial for comprehending hydrological processes . Focuses on the Wulagai river and Xiliugou river basin located in East and West Inner Mongolia. It employs hydrochemical analysis and stable HO isotopes techniques to investigate the hydrochemical properties of the basin and quantitatively assess the interconversion between groundwater and surface water. The results suggest that the Xiliugou and Wulagai river basins were originally nourished by atmospheric precipitation, with lower δD and δ18O values in groundwater compared to surface water, attributed to factors such as evaporation, water vapor source, altitude, and latitude. The surface waters in the Xiliugou and Wulagai River exhibit dominance of Na•Ca-SO4•HCO3 and Ca•Na-HCO3 types, respectively, while the groundwater is characterized by dominance of Na•Ca-HCO3 and Ca•Mg-HCO3 types, respectively. The water chemistry of surface water and groundwater in the two basins is influenced by water-rock interactions and processes of evaporation and concentration, primarily observed in the dissolution of carbonate rocks and evaporites. Hydrograph separation using End-Members Mixing Analysis (EMMA) revealed that during the growing season, groundwater in Xiliugou was primarily recharged by precipitation (76.87 %) and surface water (23.13 %), while in Wulagai, groundwater was mainly recharged by precipitation (65 %) and surface water (35 %). The presence of comparable hydrochemical constituents and shared regulatory mechanisms between groundwater and surface water within a given basin provides further evidence of a discernible hydraulic interconnection, primarily driven by the replenishment of groundwater through surface water recharge.

Deformation and mineralizing fluid circulation of gold-silver-bearing quartz veins in the Yushishan gold deposit, Altyn Mountain, northwestern China

Understanding the coupled process of deformed microstructure and fluid evolution of ore veins therefore provides insight into processes that influence mineralization distribution and its mechanism. Gold is often developed in quartz veins in many gold deposits. This paper presents detailed evidence for solid deformation, hydrothermal fluid, and mineralization in a fault-controlled gold-silver-bearing quartz vein from the Yushishan gold deposit, Altyn Mountain, NW China. Macro-and microstructure combined quartz crystal preferred orientation (CPO) unravel the ductile–brittle transition deformation of quartz veins formed at the deep crustal level ca. 9 ∼ 13 km and the deformation temperature ranging between 180 ∼ 381 °C. The homogenization temperatures and salinities of fluid inclusions change slightly, while the trapping pressure of fluid inclusions has a large fluctuation of ca. 125 ∼ 275Mpa. HO isotopes and the composition of fluid inclusions decipher the source of ore-forming fluid mainly related to the regional magmatic-metamorphic event. Combined with the fluid immiscibility that is evidenced by different types of fluid inclusion coexistence characteristics and the pH increase induced by CO2 degassing in an inhomogeneous fluid system, it is suggested that an obvious fluid overpressure and rapid decompression occur during Au deposition from the quartz vein. The seismically fractured opening and healing of rocks during ductile–brittle deformation controls the formation of the mineralization and fluid circulation. There has positive feedback between the fluid overpressure evolution, strain localization and mineralization through time. The channelized and circulated fluid flow triggered extensive veining, mineral growth, and connections with fluid reservoirs.

Timing and ore genesis of the Ciweigou low-sulfidation epithermal gold deposit in the Yanbian Cu-Au district, NE China

The Ciweigou low-17 sulfidation epithermal Cu-Au mining district, NE China, is hosted by Early Cretaceous andesite of the Jingouling Formation. From bottom to top (not explored below the 100 m level), the ore bodies consist of gold-bearing quartz veins, gold-bearing quartz-calcite veins, and calcite veins and the sides are stockwork veins and hydrothermal breccia ore bodies. Five mineralization stages are distinguished: (I) pyrite-sericite, (II) quartz-calcite, (III) grey quartz, (IV) milky quartz-adularia and (V) late carbonate. Au-bearing minerals deposited in stages II and III. Hydrothermal alteration is composed of an inner silicic-pyritic zone, intermediate zone of quartz-sericite-adularia, outer zone of quartz-chlorite-epidote and upper zone of calcite. Systematic fluid inclusion petrography shows that two-phase vapour-rich and liquid-rich inclusions are the dominant fluid inclusions types in the quartz and calcite veins, suggesting that the ore-forming fluids belong to a moderate- to low-temperature (140 °C−320 °C) and low-salinity (0 wt%−14 wt% NaCl-eqv.) H2O-NaCl-CO2 system. HO isotopes (δ18OH2O = -14.0 ‰ to −4.9 ‰ and δD = −123.4 ‰ to −88.1 ‰) indicate that the ore-forming fluids likely originated from mixed fluids driven by residual andesitic magmatic fluid. The precipitation mechanisms are mixing and major fluid boiling. The comprehensive geological and isotopic characteristics show that the Ciweigou deposit is a low-sulfidation epithermal deposit. Six pyrite samples from stages I and II yielded a Rb-Sr isochron age of 102.6 ± 2.2 Ma (MSWD = 1.19), consistent with other low-sulfidation epithermal gold mineralization ages in the Yanbian district and Lesser Xing'an Range. The timing of the Ciweigou gold mineralization at ∼103 Ma postdates the eruption of andesitic magma (106.4 ± 2.1 Ma, zircon U–Pb) and granodiorite porphyry (106.6 ± 1.2 Ma, zircon U–Pb) and diorite porphyry (107.8 ± 1.8 Ma, zircon U–Pb) emplacement, suiting in an extensional environment attributed to the rollback of the subducting Paleo-Pacific Plate.

Stable isotopes (H, O, S) signatures evidencing evolutionary trends of Brazilian spas groundwaters

This paper reports a stable isotope (H, O, S) study of groundwater samples (25) in 10 spas from southeast Brazil. They are cold (25 °C, 36%), hypothermal (25–33 °C, 60%) and mesothermal (33–36 °C, 4%) waters; and are predominantly composed of bicarbonate, carbonate and sodium. Dissolved sulfate is the dominant anion in one water sample and its concentration increased with increase in pH, electrical conductivity (EC) and total dissolved solids (TDS) values in the samples. 2H and 18O data reported in the literature for circa 700 rainwater samples collected in São Paulo State and Brasília airport, Brazil, were used to construct the following regional meteoric waterline (RMWL): δ2H V-SMOW (‰) = 8.06 δ18Owater V-SMOW (‰) + 12.85. The HO isotopes of the studied groundwater samples show a δ18Owater variation of −14.1 to −5.3‰ V-SMOW, whereas the δ2H range was −66.5 to −31.7‰ V-SMOW, which was plotted on or near the RMWL, suggesting a meteoric origin for them. However, one hypothermal water sample (29 °C) plotted away from this RMWL, and is from a deep fractured aquifer which mainly occurs in fenitization aureole rocks surrounding the carbonatite complex at Araxá spa, Minas Gerais State, and a magmatic hydrothermal water may contribute to this water sample. The use of both δ34Ssulfate and δ18Osulfate values in the selected sites permitted the plotting of a mixture line of the dissolved sulfate in the different aquifer systems of this study, considering two major sources as endmembers: sulfide oxidation, SOX (δ34Ssulfate = +1‰ and δ18Osulfate = +1‰) and sulfates possessing δ34Ssulfate = +9‰ and δ18Osulfate = +21‰ (OSW). This is an unusual isotopic composition opposite from that of sea water. The δ34Ssulfate and δ18Osulfate values tend to increase with increase in dissolved sulfate concentration. The OS isotopes signatures that deviated from the general mixture line could be due to several processes, including atmospheric deposition, SO2 oxidation in the atmosphere, soil-derived sulfate, sulfide oxidation, evaporites dissolution and the presence of dissimilatory sulfate-reducing bacteria. Three sulfate isotope composition of spring waters from Águas da Prata spa in the Poços de Caldas alkaline massif (PCAM) represented endmember sources that defined a triangle around the remaining PCAM samples, as well as the samples from the crystalline basement, São Francisco craton, and Alto Paranaíba igneous province (APIP). Such triangle allows for estimation of the relative isotopic contribution in the different spas groundwaters, which is a new approach that focuses on the use of δ34Ssulfate-δ18Osulfate pair in environmental studies, and shows its usefulness in addition to other conventional hydrogeochemical fingerprints.

$$^{163}$$ 163 Ho Distillation and Implantation for HOLMES Experiment

HOLMES is an experiment to directly measure the neutrino mass with a calorimetric approach. The calorimetric technique eliminates several systematic uncertainties usually present in spectrometers where the external source and decays to excited states affect the measurement. \(^{163}\hbox {Ho}\) is chosen as source for its very low Q value (2.8 keV), the proximity of the end-point to resonance M1 and its half life (4570 year). These features are optimal to reach simultaneously a reasonable activity to have sufficient statistics in the end-point and a small quantity of \(^{163}\hbox {Ho}\) embedded in the detector not to alter significantly its heat capacity. \(^{163}\hbox {Ho}\) will be produced via neutron irradiation of enriched \(^{162}\hbox {Er}_{2}\hbox {O}_{3}\) at the Institute Laue–Langevin (Grenoble, France), and chemically separated at Paul Scherrer Institut (Villigen, Switzerland). It will arrive at INFN laboratory of Genova in oxide form (\(\hbox {Ho}_{2}\hbox {O}_{3}\)) with traces of others Ho isotopes and contaminants not removable using chemical methods. In particular, the metastable \(^{166\hbox {m}}\hbox {Ho}\) undergoes beta decay with a half life of about 1200 year, if present \(^{166\hbox {m}}\hbox {Ho}\) induces background below 5 keV. The removal of these contaminants is critical for HOLMES so a dedicated system is being set up. The system is designed to achieve an optimal mass separation for \(^{163}\hbox {Ho}\) and consists of two main components: an evaporation chamber and an ion implanter. In the evaporation chamber, holmium will be reduced in metallic form, using the reaction \(\hbox {2Y+Ho}_{2}\hbox {O}_{3}\rightarrow \)\(\hbox {Y}_{2}\hbox {O}_{3}\hbox {+2Ho}\) and used to produce a metallic target for the ion implanter source. The ion implanter consists of five main components: a Penning sputter ion source, an acceleration section, a magnetic/electrostatic mass analyser, a magnetic scanning stage and a focusing electrostatic triplet. In this contribution, we describe the procedures, under continuous refinement, for the holmium evaporation process, the ion-implanted metallic target production and the status of the ion implanter.

Magnetic moments and g-factors in odd-A Ho isotopes**Supported by Scientific and Technological Research Council of Turkey (TUBITAK) (115F564)

The ground-state magnetic moment, gK factor and quenching spin gyromagnetic ratio have been calculated using the microscopic method based on the Quasiparticle Phonon Nuclear Model (QPNM) for 155−169Ho nuclei for the first time. It is shown that the residual spin-spin interactions are responsible for the core polarization, and because of the core polarization the spin gyromagnetic factors are quenched. By considering the core polarization effects, a satisfactory agreement is obtained for the computed ground state gK factor, which gives an intrinsic contribution to the magnetic moments. In order to assess the collective contribution to the magnetic moments, the rotational gyromagnetic factors gR have been also calculated within the cranking approximation using the single particle wave function of the axially symmetric Woods-Saxon potential. For the ground-state magnetic moments of odd-proton 155−165Ho nuclei, a good description of the experimental data is obtained with an accuracy of 0.01–0.1 μN. From systematic trends, the quenching spin gyromagnetic factor, gK factor and magnetic moment have also been theoretically predicted for 167,169Ho where there is no existing experimental data.

Microscopic investigation of the low-lying magnetic dipole transitions in the odd-mass 155–169Ho isotopes

The low-lying magnetic dipole (M1) strength in deformed odd-mass 155–169Ho nuclei is investigated using rotational invariant (RI-) Quasiparticle Phonon Nuclear Model (QPNM). The gross features and fragmentation of the scissors mode in 165Ho is well reproduced by RI-QPNM calculations. The systematics of the low-energy M1 excitation in Ho isotopic chain is discussed with respect to summed strength. Besides, the results for M1 excitations in odd-mass Ho isotopes are compared with the systematics of the scissors mode in the neighbouring even–even nuclei. The obtained results generally match the systematic and trends typical for the scissors motion. In addition to the low-lying M1 excitations, a M1 giant resonance in the 7–15 MeV energy region is predicted for 155–169Ho nuclei in the present study.

Microscopic insight into the study of band spectra of 158Ho and 159,161,163Ho isotopes

The nuclear structure properties of the low-lying and excited states of Holmium isotopes have been studied within the framework of Projected Shell Model. The theoretical results are found to be in the reasonable agreement with the observed ones. The theoretical B(M1)/B(E2) estimates of 158Ho are seen to reproduce the same systematics as shown by the observed ones. However, for 159,161,163Ho, the B(E2) transition probabilities for the ground state band have been predicted for transitions for which the experimental values are not available.

High-spin yrast structure of159Ho

An investigation of the yrast structure of the odd-$Z$ ${}^{159}$Ho nucleus to high spin has been performed. The ${}^{159}$Ho nucleus was populated by the reaction ${}^{116}$Cd(${}^{48}$Ca,$p4n\ensuremath{\gamma}$) at a beam energy of 215 MeV, and resulting $\ensuremath{\gamma}$ decays were detected by the Gammasphere spectrometer. The ${h}_{11/2}$ yrast band has been significantly extended up to ${I}^{\ensuremath{\pi}}=75/{2}^{\ensuremath{-}}$ (tentatively $79/{2}^{\ensuremath{-}}$). A lower frequency limit for the second ${({h}_{11/2})}^{2}$ proton alignment was extracted consistent with the systematics of this alignment frequency, indicating an increased deformation with neutron number in the Ho isotopes. The energy-level splitting between the signature partners in the ${h}_{11/2}$ structures of the Ho isotopes and the neighboring $N=92$ isotones is discussed.

Labelling of proteins with 2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid and lanthanides and detection by ICP-MS

The labelling of two different proteins (bovine serum albumin, hen egg white lysozyme) with the commercially available chelating compound 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (p-SCN-Bn-DOTA) has been investigated. The assay described here has been optimised for the application to detect proteins labelled by stable isotopes of Eu, Tb and Ho and separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Detection has been performed by laser ablation ICP-MS after electroblotting of the target proteins onto NC membranes. A range of total protein amounts from 0.015 pmol (BSA) to 105 pmol (lysozyme) has been covered. A calibration was performed for BSA in the range from 0.015 to 15 pmol and a limit of detection below 15 fmol can be estimated. For lysozyme integrated sensitivities of more than 107 cps pmol−1 of protein have been realized. The conditions, once optimised for labelling with Eu, have been applied for other lanthanides (Tb, Ho), too. ESI-MS of the intact and the tryptic digested lysozyme has been used as to provide a better understanding of the reaction chemistry and efficiency. The procedure described here looks promising to develop multielement labelling strategies (multiplexing) for ICP-MS applications in quantitative proteomics.

Evidence for triaxial deformation nearN=86:Collective bands in152,153Dyand153Ho

The $N=86,87$ isotopes of dysprosium and holmium have been investigated using the Eurogam II $\ensuremath{\gamma}$-ray spectrometer. A new collective rotational band has been observed in ${}^{153}\mathrm{Ho}$ and the previously observed $\ensuremath{\nu}{\mathrm{i}}_{13/2}$ band in ${}^{153}\mathrm{Dy}$ has been extended to much higher spin. Comparing these bands and similar bands in ${}^{152}\mathrm{Dy}$ with the collective bands in the $N=90$ isotopes of Dy, Ho, and Er suggests that the first ${h}_{11/2}$ proton crossing is not observed at $N=86,87.$ This observation has led to the reinterpretation of four of the previously observed bands in ${}^{152}\mathrm{Dy}.$ It is proposed that the low deformation collective bands in ${}^{152,153}\mathrm{Dy}$ and ${}^{153}\mathrm{Ho}$ are associated with a triaxial shape with large positive gamma and that they have a similar origin to the recently observed triaxial superdeformed bands in ${}^{163--165}\mathrm{Lu}.$

Systematic study of neutron-deficient Ho isotopes in a relativistic mean field theory.

We have calculated the binding energies, rms radii, and multipole moments of Ho isotopes ([ital N]=81--98) using a relativistic mean field theory. The quadrupole moments and the change in mean square charge radius are compared with the experimental and other theoretical results. We observed a shape transition from oblate to prolate deformations in going from lighter to heavier isotopes.

Microscopic description of vibrational degrees of freedom in odd-odd isotopes of Ho

The microscopic approach for the description of low-lying intrinsic states in deformed odd-odd nuclei is formulated as a generalization of the quasiparticle-phonon model. In comparison with other models used for deformed odd-odd nuclei, the approach proposed in this paper involves vibrational degrees of freedom of the doubly-even core, their coupling to quasiparticle degrees of freedom and then-p interaction between the odd particles. Our model treats all of these modes of nuclear motion on the same microscopic footing. This proposed model is applied to calculate the energies and phonon-quasiparticle structure of the intrinsic states of the odd-odd Ho isotopes withA=160, 162, 164, 166 and 168. It is found that the low-lying intrinsic states in the odd-odd Ho isotopes have only small vibrational components. In general the vibrational states are fragmented over many intrinsic states.

A new TRISTAN thermal ion source

A new thermal ion source with an integrated target which is heated by electron bombardment to a temperature of 2500°C has been developed for the TRISTAN on-line fission product mass separator at Brookhaven National Laboratory. Initial on-line tests demonstrated that this ion source can extend the range of accessible elements to the rare-earth region. Yields are presented for isotopes of Ce, Pr, Pm, Sm, Eu, Gd, Tb, Dy, ho, Ga, Ge, As, Y, Zr, Nb, In, Sn and Sb.

Cross sections for evaporation residue production near theN=126 shell closure

In fusion reactions of40Ar with isotopes of Ho, Tm, Yb, Lu, Hf and Ta, cross sections for the production of proton-rich evaporation-residues near the 126 neutron shell were measured. This first comprehensive study of very fissile spherical residues reveals a surprisingly low stabilizing influence of the sphericalN=126 shell on the survival probability. The experimental results are compared with evaporation calculations. Conclusions for the production of superheavy nuclei are drawn.

Rotational bands and fast el transitions in 163Ho

The level scheme of the deformed odd-proton nucleus 163Ho has been investigated by in-beam and decay spectroscopic methods. Single γ-ray spectra, conversion electron spectra, γ-γ coincidences and angular distributions of the γ-rays were measured in the reaction 163Dy(d, 2nγ) at a deuteron energy of about 13.5 MeV. Single γ-ray spectra were also taken in the 163Dy(p, nγ) reaction with 6.7 MeV protons. Additional information on the 163Ho level scheme was obtained by re-investigating the γ-radiation in the electron capture decay of 163Er. The proposed level scheme of 163Ho contains in addition to the ground state band 7 2 − [523] the rotational bands built on the intrinsic states 7 2 + [404], 3 2 + [411], 1 2 + [411] and 7 2 − [541] (band heads at 439.94, 360.36, 297.88 and 471.25 keV, respectively). Further levels at 1113.5, 876.0 and 614.3 keV are interpreted as being mainly the quasiparticle excitations 5 2 − [532], 5 2 + [413] and possibly the ground state γ-vibration, respectively. A comparison of the quasiparticle excitations in the Ho isotopes is performed on the basis of the Nilsson model including pairing corrections. Discontinuities in the rotational bands are described by Coriolis coupling effects. Several fast E1 interband transitions were observed in 163Ho. Some of them connect levels of the 1 2 + [411] band with the ground state band 7 2 − [523]. The appearance of these K-forbidden transitions is explained by a weak mixing between states of the bands 7 2 + [411] and 7 2 + [404] caused by Coriolis interaction.

Separation and pairing energies involving isotopes of Tb, Dy, Ho, Er, Tm, Yb, Lu and Hf

Abstract Fifteen new atomic mass difference determinations are combined with a large body of reaction and decay data in a recalculation of the separation and pairing energies for Hf and the heavier rare earth nuclei. The accuracy and reliability of the data are such that definite systematic trends are observed. The data have also allowed the accurate determination of three decay Q -values which were previously unknown.

Lifetimes of E3 transitions in the odd-mass Ho isotopes

The half-lives of the 206 keV E3 transition in 159Ho and the 211 keV E3 transition in 161Ho have been measured to be 6.9±0.3 s and 6.1±0.3 s, respectively, and the existence of a 305 keV E3 transition in 163Ho with a half-life of 1.1±0.1 s has been confirmed.

REACTIONS PRODUCED ON ERBIUM BY PROTONS OF ENERGIES BETWEEN 6 AND 87 MEV

Erbium was bombarded with protons of energies varying between 6 and 87 Mev. Nuclear characteristics and excitation functions were studied for isotopes of Tm, Er, Ho, and Dy, formed by various (p,xn) and (p,xpxn) reactions. Bombardment of enriched Er isotopes helped elucidate some of the excitation functions. A comparison has been made of the experimental (p,xn) cross sections with those predicted by the Jackson model and reasonable agreement has been found. Holmium was bombarded with α-particles to produce the compound nucleus Tm169* and the ratios σ (p,n): σ (p,2n) = σ (α,n): σ(α,2n) were found to hold.

Nuclear Spectroscopy of Odd-Mass (161-173) Nuclides Produced by Proton Irradiation of Er and Yb

To study the effect of nucleon number on nuclear levels of odd-mass rare-earth isotopes, enriched isotopes of Er and Yb were irradiated with protons in the ORNL 86-inch Cyclotron. After chemical separation, the decay chains leading to stable isotopes were analyzed with internal-conversion, photographic-recording, permanent-magnet spectrographs. Precise energy values as well as photometrically measured intensities of conversion lines of 8 to 1600 kev energy were obtained. Very light isotopes of Lu and Tm, each eight mass units from the mass stability line, were produced. The following activities were studied: ${\mathrm{Tm}}^{161}$, (\ensuremath{\sim}30 min), ${\mathrm{Ho}}^{161m}$ ($E3$, 211 kev), ${\mathrm{Tm}}^{163}$ (2 hr), and ${\mathrm{Lu}}^{167}$ (54 min), all previously unreported, as well as ${\mathrm{Tb}}^{161}$, ${\mathrm{Ho}}^{161}$, ${\mathrm{Tm}}^{165,167}$, ${\mathrm{Yb}}^{167}$, ${\mathrm{Lu}}^{169,171,173}$, ${\mathrm{Hf}}^{173}$, and possibly ${\mathrm{Yb}}^{169m}$. Genetic relationships and partial level schemes for decay chains of masses 151 to 173 are shown. Where comparison is possible, excellent agreement with the predictions of Mottelson and Nilsson is obtained, particularly for the case of the various isotopes of Tb ($Z=65$), Ho ($Z=67$), and Tm ($Z=69$), where striking similarities in the level structure are observed.