Peters, Stefan T. M.

[["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Paleoceanography and Paleoclimatology"],["dc.bibliographiccitation.volume","36"],["dc.contributor.author","Fischer, Meike B."],["dc.contributor.author","Oeser, Martin"],["dc.contributor.author","Weyer, Stefan"],["dc.contributor.author","Folco, Luigi"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Zahnow, Fabian"],["dc.contributor.author","Pack, Andreas"],["dc.date.accessioned","2021-06-01T09:41:37Z"],["dc.date.available","2021-06-01T09:41:37Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1029/2020PA004159"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/84980"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-425"],["dc.relation.eissn","2572-4525"],["dc.relation.issn","2572-4517"],["dc.title","I‐Type Cosmic Spherules as Proxy for the Δ′ 17 O of the Atmosphere—A Calibration With Quaternary Air"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1495"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","Rapid Communications in Mass Spectrometry"],["dc.bibliographiccitation.lastpage","1504"],["dc.bibliographiccitation.volume","30"],["dc.contributor.author","Pack, Andreas"],["dc.contributor.author","Tanaka, Ryoji"],["dc.contributor.author","Hering, Markus"],["dc.contributor.author","Sengupta, Sukanya"],["dc.contributor.author","Peters, Stefan"],["dc.contributor.author","Nakamura, Eizo"],["dc.date.accessioned","2018-11-07T10:11:34Z"],["dc.date.available","2018-11-07T10:11:34Z"],["dc.date.issued","2016"],["dc.description.abstract","RATIONALE: The precise determination of Delta'O-17 values in terrestrial material is becoming increasingly important to understand the mass-dependent fractionation processes that cause variations in oxygen isotope ratios. San Carlos olivine is widely used as the reference material for oxygen isotope measurements of terrestrial and extraterrestrial materials. We report new Delta'O-17 values for San Carlos olivine that were independently determined in two different laboratories (Geoscience Center [GZG], University of Gottingen) and Institute for Study of the Earth's Interior [ISEI], Okayama University, Misasa) in direct comparison with VSMOW2 and SLAP2 water standards. METHODS: The delta O-17 and delta O-18 values of VSMOW2, SLAP2, GISP, and San Carlos olivine were determined relative to reference gas. In both laboratories, water and San Carlos olivine samples were prepared by BrF5 fluorination. In both laboratories, the O-2 released from water and olivine samples was passed through the same purification system and measured using the same mass spectrometer relative to the same reference gas. RESULTS: In both laboratories, the delta O-17(VSMOW2) and delta O-18 (VSMOW2) scales were slightly compressed with respect to the recommended composition of VSMOW2 and SLAP2. The new Delta'O-17(0.528) value (calculated from the VSMOW2-SLAP2 scaled 6 values) of San Carlos olivine from GZG was -36 +/- 9 ppm and, from ISEI, a value of -40 +/- 7 ppm (1(7 standard deviation) was determined. These values are similar to 50 ppm higher than previously reported from the same laboratories. Possible causes for the observed discrepancies are discussed. CONCLUSIONS: The results of this study in comparison with previous data from the same laboratories demonstrated that for high accuracy determination of Delta'O-17 values: (i) calibration of the reference gas relative to O-2 released from primary standards (VSMOW2, SLAP2) in the same laboratory is highly recommended, (ii) non-linearity of the mass spectrometer may not only affect delta O-17 and delta O-18 values but also Delta'O-17 values, and (iii) the VSMOW2-SLAP2 scaling should also be applied to analyses of rocks and minerals. Studies that are concerned with small differences in Delta'O-17 at similar delta O-18 values, however, are not affected by non-linearity of the mass spectrometer. Copyright (C) 2016 John Wiley & Sons, Ltd."],["dc.identifier.doi","10.1002/rcm.7582"],["dc.identifier.isi","000379974500007"],["dc.identifier.pmid","27321837"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/40075"],["dc.language.iso","en"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1097-0231"],["dc.relation.issn","0951-4198"],["dc.title","The oxygen isotope composition of San Carlos olivine on the VSMOW2-SLAP2 scale"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","132"],["dc.bibliographiccitation.journal","Chemical Geology"],["dc.bibliographiccitation.lastpage","145"],["dc.bibliographiccitation.volume","413"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Muenker, Carsten"],["dc.contributor.author","Wombacher, Frank"],["dc.contributor.author","Elfers, Bo-Magnus"],["dc.date.accessioned","2018-11-07T09:50:10Z"],["dc.date.available","2018-11-07T09:50:10Z"],["dc.date.issued","2015"],["dc.description.abstract","Analytical protocols for measurements of isotope ratios involving low-abundance isotopes Hf-174 (similar to 0.16%), W-180 (similar to 0.12%), and Pt-190 (similar to 0.014%) usingmulti-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) at ca. tenfold improved precision compared to previous studies are presented. The improvements in precision result in part from the use of Faraday amplifiers equipped with 10(12) Omega resistors for collection of the isotope beams of interest, as well as for the isotope beams used to monitor isobaric interferences. For ion currents >5 x 10(-13) A (>50 mV on an amplifier with 10(11) Omega resistor), uncertainties (2 s. d.) of better than 100 ppm are typically achieved for isotope ratios involving Hf-174, W-180 and Pt-190. Terrestrial isotope abundances (atomic percent +/- 2 s.d.) of Hf-174 (0.16106 +/- 0.00006; n=15); W-180(0.11910 +/- 0.00009; n=10); and Pt-190 (0.01286 +/- 0.00005; n = 9) were determined on reference solutions throughout multiple analytical sessions over similar to 3 years. The results, however, rely on the accuracy of the reference value chosen for the isotope ratios employed for mass bias correction and, to a lesser extent, on the accuracy of the exponential mass fractionation law used for mass bias correction. For the precise determination of isotope ratios involving Hf-174, W-180 and Pt-190 in natural materials, efficient chromatographic separation schemes for Hf and W from silicate-rich matrices, and for Pt from iron meteorite matrices, are presented that provide effective separation of the element of interest from interfering elements. First results for Pt suggest that IAB, IIAB and IIIAB iron meteorites exhibit terrestrial Pt-190 abundances within uncertainty. Three chondrite samples exhibit indistinguishable Hf-174 from terrestrial Hf. The isotope abundance of W-180 in meteorites is more variable due to radiogenic W-180 that was produced by Os-184-decay. (C) 2015 Elsevier B.V. All rights reserved."],["dc.description.sponsorship","DFG [MU 1406/10-1/2]"],["dc.identifier.doi","10.1016/j.chemgeo.2015.08.018"],["dc.identifier.isi","000361845700012"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35653"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","1878-5999"],["dc.relation.issn","0009-2541"],["dc.title","Precise determination of low abundance isotopes (Hf-174, W-180 and Pt-190) in terrestrial materials and meteorites using multiple collector ICP-MS equipped with 10(12) Omega Faraday amplifiers"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","70"],["dc.bibliographiccitation.journal","Earth and Planetary Science Letters"],["dc.bibliographiccitation.lastpage","79"],["dc.bibliographiccitation.volume","459"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Muenker, Carsten"],["dc.contributor.author","Pfeifer, Markus"],["dc.contributor.author","Elfers, Bo-Magnus"],["dc.contributor.author","Sprung, Peter"],["dc.date.accessioned","2018-11-07T10:28:07Z"],["dc.date.available","2018-11-07T10:28:07Z"],["dc.date.issued","2017"],["dc.description.abstract","Some nuclides that were produced in supernovae are heterogeneously distributed between different meteoritic materials. In some cases these heterogeneities have been interpreted as the result of interaction between ejecta from a nearby supernova and the nascent solar system. Particularly in the case of the oldest objects that formed in the solar system - Ca-Al rich inclusions (CAls) - this view is confirm the hypothesis that a nearby supernova event facilitated or even triggered solar system formation. We present Hf isotope data for bulk meteorites, terrestrial materials and CAIs, for the first time including the low-abundance isotope Hf-174 (similar to 0.16%). This rare isotope was likely produced during explosive 0/Ne shell burning in massive stars (i.e., the classical \"p-process\"), and therefore its abundance potentially provides a sensitive tracer for putative heterogeneities within the solar system that were introduced by supernova ejecta. For CAls and one LL chondrite, also complementary W isotope data are reported for the same sample cuts. Once corrected for small neutron capture effects, different chondrite groups, eucrites, a silicate inclusion of a JAB iron meteorite, and terrestrial materials display homogeneous Hf isotope compositions including 174Hf. Hafnium-174 was thus uniformly distributed in the inner solar system when planetesimals formed at the <50 ppm level. This finding is in good agreement with the evidently homogeneous distributions of p-process isotopes W-180, Os-184 and possibly Pt-180 between different iron meteorite groups. In contrast to bulk meteorite samples, CAls show variable depletions in p-process 174Hf with respect to the inner solar system composition, and also variable r-process (or s-process) Hf and W contributions. Based on combined Hf and W isotope compositions, we show that CAls sampled at least one component in which the proportion of r- and s-process derived Hf and W deviates from that of supernova ejecta. The Hf and W isotope anomalies in CAls are therefore best explained by selective processing of presolar carrier phases prior to CAI formation, and not by a late injection of supernova materials. Likewise, other isotope anomalies in additional elements in CAIs relative to the bulk solar system may reflect the same process. The isotopic heterogeneities between the first refractory condensates may have been eradicated partially during CAI formation, because W isotope anomalies in CAls appear to decrease with increasing W concentrations as inferred from time -integrated (182)w/W-184. Importantly, the Lu-178-Hf-176 and Hf-182-W-182 chronometers are not significantly affected by nucleosynthetic heterogeneity of Hf isotopes in bulk meteorites, but may be affected in CAls. (C) 2016 Elsevier B.V. All rights reserved."],["dc.description.sponsorship","DFG [MU1406/10-1/2]; Gottingen University [6125/3917543]"],["dc.identifier.doi","10.1016/j.epsl.2016.11.009"],["dc.identifier.isi","000393006500007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/43354"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","1385-013X"],["dc.relation.issn","0012-821X"],["dc.title","Distribution of p-process Hf-174 in early solar system materials and the origin of nucleosynthetic Hf and W isotope anomalies in Ca-Al rich inclusions"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","346"],["dc.bibliographiccitation.journal","Geochimica et Cosmochimica Acta"],["dc.bibliographiccitation.lastpage","362"],["dc.bibliographiccitation.volume","239"],["dc.contributor.author","Elfers, Bo-Magnus"],["dc.contributor.author","Sprung, Peter"],["dc.contributor.author","Pfeifer, Markus"],["dc.contributor.author","Wombacher, Frank"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Münker, Carsten"],["dc.date.accessioned","2019-07-24T07:38:21Z"],["dc.date.available","2019-07-24T07:38:21Z"],["dc.date.issued","2018"],["dc.description.abstract","The stepwise acid digestion of primitive chondritic meteorites allows the identification of nucleosynthetic isotope anomalies that are otherwise hidden on the bulk rock scale. Here, we present combined Hf and W isotope data for acid leachates, residues, and bulk rock aliquots of several primitive chondrites that include highly precise analyses of the heavy p-process isotopes ¹⁷⁴Hf and ¹⁸⁰W. Including data for these two p-process isotopes enables, for the first time, the clear-cut discrimination between s- and r-process contributions to the Hf and W isotope inventory. Our analyses reveal Hf and W isotopic homogeneity at the bulk rock scale, but significant Hf and W isotope anomalies that are complementary between acid leachates and residues. Since both r- to p-process isotope ratios are invariant in leachates and residues, the observed anomalies can unambiguously be tied to variable contributions of carrier phases enriched in s-process nuclides, as previously inferred for, i.e., Mo and Ru in leaching experiments. Hafnium and W isotope anomalies co-vary in leachate and residue fractions from CM chondrites, whereas CO and CV chondrites are characterized by distinctly larger Hf isotope anomalies compared to W. This observation is most likely explained by more efficient homogenization of s-process W carrier(s) or, alternatively, by local redistribution of anomalous W into secondary less resistant phases during parent body and/or nebular processing. This implies the presence of different s-nuclide carrier phases for Hf and W. Several carriers of s-process-material appear to have been selectively dissolved by our leaching protocol, while contributions from r- and p-process Hf and W carrier phases appear invariant, possibly due to the generally more labile nature of their carrier phases during solar nebula and/or parent body processing."],["dc.identifier.doi","10.1016/j.gca.2018.08.009"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/61964"],["dc.language.iso","en"],["dc.relation.issn","0016-7037"],["dc.title","Variable distribution of s-process Hf and W isotope carriers in chondritic meteorites – Evidence from 174Hf and 180W"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","236"],["dc.bibliographiccitation.journal","Geochimica et Cosmochimica Acta"],["dc.bibliographiccitation.lastpage","239"],["dc.bibliographiccitation.volume","169"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Muenker, Carsten"],["dc.contributor.author","Becker, Harry"],["dc.contributor.author","Schulz, Toni"],["dc.date.accessioned","2018-11-07T09:48:55Z"],["dc.date.available","2018-11-07T09:48:55Z"],["dc.date.issued","2015"],["dc.identifier.doi","10.1016/j.gca.2015.06.030"],["dc.identifier.isi","000362975700015"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35406"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Pergamon-elsevier Science Ltd"],["dc.relation.issn","1872-9533"],["dc.relation.issn","0016-7037"],["dc.title","Comment on \"Cosmogenic W-180 variations in meteorites and re-assessment of a possible Os-184-W-180 decay system\" by Cook, DL, Kruijer, T., Leya, I., Kleine, T."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.subtype","letter_note"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","130"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of Analytical Atomic Spectrometry"],["dc.bibliographiccitation.lastpage","143"],["dc.bibliographiccitation.volume","32"],["dc.contributor.author","Pfeifer, M."],["dc.contributor.author","Lloyd, N. S."],["dc.contributor.author","Peters, S. T. M."],["dc.contributor.author","Wombacher, F."],["dc.contributor.author","Elfers, B.-M."],["dc.contributor.author","Schulz, T."],["dc.contributor.author","Münker, C."],["dc.date.accessioned","2020-12-10T18:11:13Z"],["dc.date.available","2020-12-10T18:11:13Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1039/C6JA00329J"],["dc.identifier.eissn","1364-5544"],["dc.identifier.issn","0267-9477"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73926"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Tantalum isotope ratio measurements and isotope abundances determined by MC-ICP-MS using amplifiers equipped with 10 10 , 10 12 and 10 13 Ohm resistors"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","maps.13905"],["dc.bibliographiccitation.journal","Meteoritics & Planetary Science"],["dc.contributor.author","Bischoff, Addi"],["dc.contributor.author","Patzek, Markus"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Barrat, Jean‐Alix"],["dc.contributor.author","Di Rocco, Tommaso"],["dc.contributor.author","Pack, Andreas"],["dc.contributor.author","Ebert, Samuel"],["dc.contributor.author","Jansen, Christian A."],["dc.contributor.author","Kmieciak, Kryspin"],["dc.date.accessioned","2022-09-01T09:50:43Z"],["dc.date.available","2022-09-01T09:50:43Z"],["dc.date.issued","2022"],["dc.description.sponsorship"," Alexander von Humboldt-Stiftung https://doi.org/10.13039/100005156"],["dc.description.sponsorship"," Deutsche Forschungsgemeinschaft https://doi.org/10.13039/501100001659"],["dc.identifier.doi","10.1111/maps.13905"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/113785"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-597"],["dc.relation.eissn","1945-5100"],["dc.relation.issn","1086-9379"],["dc.rights.uri","http://creativecommons.org/licenses/by-nc-nd/4.0/"],["dc.title","The chondrite breccia of Antonin (\n L4\n ‐5)—A new meteorite fall from Poland with a heterogeneous distribution of metal"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]