Author
Anton Wallner
Other affiliations: Ludwig Maximilian University of Munich, Technische Universität München, Charles University in Prague ...read more
Bio: Anton Wallner is an academic researcher from Australian National University. The author has contributed to research in topics: Neutron & Neutron cross section. The author has an hindex of 30, co-authored 342 publications receiving 6827 citations. Previous affiliations of Anton Wallner include Ludwig Maximilian University of Munich & Technische Universität München.
Papers published on a yearly basis
Papers
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Los Alamos National Laboratory1, Brookhaven National Laboratory2, Oak Ridge National Laboratory3, Rensselaer Polytechnic Institute4, Argonne National Laboratory5, Lawrence Livermore National Laboratory6, International Atomic Energy Agency7, National Institute of Standards and Technology8, Japan Atomic Energy Agency9, Idaho National Laboratory10, Jožef Stefan Institute11, Nuclear Research and Consultancy Group12, University of Vienna13
TL;DR: The ENDF/B-VII.1 library as mentioned in this paper is the most widely used data set for nuclear data analysis and has been updated several times over the last five years. But the most recent version of the ENDF-B-VI.0 library is based on the JENDL-4.0 standard.
2,171 citations
15 Jan 2010-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this article, an aliquot of highly enriched 10 Be master solution was serially diluted with increasing well-known masses of 9 Be and the specific activity was measured by means of accurate liquid scintillation counting (LSC).
Abstract: The importance of 10 Be in different applications of accelerator mass spectrometry (AMS) is well-known. In this context the half-life of 10 Be has a crucial impact, and an accurate and precise determination of the half-life is a prerequisite for many of the applications of 10 Be in cosmic-ray and earth science research. Recently, the value of the 10 Be half-life has been the centre of much debate. In order to overcome uncertainties inherent in previous determinations, we introduced a new method of high accuracy and precision. An aliquot of our highly enriched 10 Be master solution was serially diluted with increasing well-known masses of 9 Be. We then determined the initial 10 Be concentration by least square fit to the series of measurements of the resultant 10 Be/ 9 Be ratio. In order to minimize uncertainties because of mass bias which plague other low-energy mass spectrometric methods, we used for the first time Heavy-Ion Elastic Recoil Detection (HI-ERD) for the determination of the 10 Be/ 9 Be isotopic ratios, a technique which does not suffer from difficult to control mass fractionation. The specific activity of the master solution was measured by means of accurate liquid scintillation counting (LSC). The resultant combination of the 10 Be concentration and activity yields a 10 Be half-life of T 1/2 = 1.388 ± 0.018 (1 s, 1.30%) Ma. In a parallel but independent study (Chmeleff et al. [11] ), found a value of 1.386 ± 0.016 (1.15%) Ma. Our recommended weighted mean and mean standard error for the new value for 10 Be half-life based on these two independent measurements is 1.387 ± 0.012 (0.87%) Ma.
797 citations
TL;DR: A well resolved time profile of the 60Fe concentration in a deep-sea ferromanganese crust is measured and a highly significant increase 2.8 Myr ago is found.
Abstract: A nearby supernova (SN) explosion in the past can be confirmed by the detection of radioisotopes on Earth that were produced and ejected by the SN. We have now measured a well resolved time profile of the 60Fe concentration in a deep-sea ferromanganese crust and found a highly significant increase 2.8 Myr ago. The amount of 60Fe is compatible with the deposition of ejecta from a SN at a distance of a few 10 pc. The well defined time of the SN explosion makes it possible to search for plausible correlations with other events in Earth's history.
232 citations
CERN1, National Technical University of Athens2, French Alternative Energies and Atomic Energy Commission3, Istituto Nazionale di Fisica Nucleare4, Vienna University of Technology5, Goethe University Frankfurt6, Centre national de la recherche scientifique7, Charles University in Prague8, University of Manchester9, University of Zagreb10, Polytechnic University of Catalonia11, Technical University of Lisbon12, University of Seville13, Spanish National Research Council14, University of Santiago de Compostela15, Paul Scherrer Institute16, Aristotle University of Thessaloniki17, Bhabha Atomic Research Centre18, University of York19, Karlsruhe Institute of Technology20, Oak Ridge National Laboratory21, University of Bologna22, ENEA23, University of Vienna24, University of Basel25
TL;DR: In this paper, the authors present the characteristics of the new neutron beam in the currently available configurations, which correspond to two different collimation systems and two choices of neutron moderator, including the intensity and energy dependence of the neutron flux, the spatial profile of the beam, the in-beam background components and the energy resolution/broadening.
Abstract: The neutron time-of-flight facility n_TOF features a white neutron source produced by spallation through 20GeV/c protons impinging on a lead target. The facility, aiming primarily at the measurement of neutron-induced reaction cross sections, was operating at CERN between 2001 and 2004, and then underwent a major upgrade in 2008. This paper presents in detail all the characteristics of the new neutron beam in the currently available configurations, which correspond to two different collimation systems and two choices of neutron moderator. The characteristics discussed include the intensity and energy dependence of the neutron flux, the spatial profile of the beam, the in-beam background components and the energy resolution/broadening. The discussion of these features is based on dedicated measurements and Monte Carlo simulations, and includes estimations of the systematic uncertainties of the mentioned quantities.
224 citations
TL;DR: The findings indicate multiple supernova and massive-star events during the last ten million years at distances of up to 100 parsecs, which indicates that a few per cent of fresh 60Fe was captured in dust and deposited on Earth.
Abstract: Analysis of deep-ocean archives reveals that a few per cent of fresh 60Fe has been captured in interstellar dust and deposited in Earth’s crust, indicating that many supernova events occurred over the past ten million years within a distance of up to 100 parsecs from Earth. Twenty years ago it was suggested that nearby supernova explosions could leave their mark here on Earth in the shape of geological isotope anomalies caused by direct deposition of debris or through cosmic-ray spallation in the atmosphere. So it proved, with the emergence of iron-60, found in deep-sea ferromanganese crusts, as a supernova indicator. Two papers in this issue add further detail to the picture, and suggest there have been multiple supernovae within a few hundred light years, over the past few million years. Anton Wallner et al. report that the deep-sea 60Fe signal is global, extended in time and of interstellar origin from multiple events. Their results reveal 60Fe interstellar influxes onto Earth 1.7–3.2 and 6.5–8.7 million years ago. Dieter Breitschwerdt et al. report calculations of the most probable trajectories and masses of the supernova progenitors, and hence their explosion times and sites. The 60Fe signal arises from two supernovae at distances between 90 and 100 parsecs. The closest occurred 2.3 million years ago, and the second about 1.5 million years ago at 9.2 and 8.8 solar masses, respectively. The rate of supernovae in our local Galactic neighbourhood within a distance of about 100 parsecs from Earth is estimated to be one every 2–4 million years, based on the total rate in the Milky Way (2.0 ± 0.7 per century1,2). Recent massive-star and supernova activity in Earth’s vicinity may be traced by radionuclides with half-lives of up to 100 million years3,4,5,6, if trapped in interstellar dust grains that penetrate the Solar System. One such radionuclide is 60Fe (with a half-life of 2.6 million years)7,8, which is ejected in supernova explosions and winds from massive stars1,2,9. Here we report that the 60Fe signal observed previously in deep-sea crusts10,11 is global, extended in time and of interstellar origin from multiple events. We analysed deep-sea archives from all major oceans for 60Fe deposition via the accretion of interstellar dust particles. Our results reveal 60Fe interstellar influxes onto Earth at 1.5–3.2 million years ago and at 6.5–8.7 million years ago. The signal measured implies that a few per cent of fresh 60Fe was captured in dust and deposited on Earth. Our findings indicate multiple supernova and massive-star events during the last ten million years at distances of up to 100 parsecs.
187 citations
Cited by
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University of Manchester1, KEK2, CERN3, Complutense University of Madrid4, SLAC National Accelerator Laboratory5, Toyama College6, Lebedev Physical Institute7, Fermilab8, University of Paris-Sud9, Lawrence Livermore National Laboratory10, National Research Nuclear University MEPhI11, Queen's University Belfast12, Korea Institute of Science and Technology Information13, Istituto Nazionale di Fisica Nucleare14, Northeastern University15, University of Seville16, National University of Cordoba17, Saint Joseph University18, Joint Institute for Nuclear Research19, Illawarra Health & Medical Research Institute20, University of Wollongong21, Hampton University22, TRIUMF23, ETH Zurich24, University of Bordeaux25, Centre national de la recherche scientifique26, University of Helsinki27, Johns Hopkins University School of Medicine28, National Technical University of Athens29, University of Notre Dame30, Ashikaga Institute of Technology31, Kobe University32, Intelligence and National Security Alliance33, University of Trieste34, University of Warwick35, University of Belgrade36, Instituto Superior Técnico37, European Space Agency38, Varian Medical Systems39, George Washington University40, Ritsumeikan University41, Ton Duc Thang University42, Université Paris-Saclay43, Idaho State University44, Naruto University of Education45
01 Nov 2016-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: Geant4 as discussed by the authors is a software toolkit for the simulation of the passage of particles through matter, which is used by a large number of experiments and projects in a variety of application domains, including high energy physics, astrophysics and space science, medical physics and radiation protection.
Abstract: Geant4 is a software toolkit for the simulation of the passage of particles through matter. It is used by a large number of experiments and projects in a variety of application domains, including high energy physics, astrophysics and space science, medical physics and radiation protection. Over the past several years, major changes have been made to the toolkit in order to accommodate the needs of these user communities, and to efficiently exploit the growth of computing power made available by advances in technology. The adaptation of Geant4 to multithreading, advances in physics, detector modeling and visualization, extensions to the toolkit, including biasing and reverse Monte Carlo, and tools for physics and release validation are discussed here.
2,260 citations
Los Alamos National Laboratory1, Brookhaven National Laboratory2, Oak Ridge National Laboratory3, Rensselaer Polytechnic Institute4, Argonne National Laboratory5, Lawrence Livermore National Laboratory6, International Atomic Energy Agency7, National Institute of Standards and Technology8, Japan Atomic Energy Agency9, Idaho National Laboratory10, Jožef Stefan Institute11, Nuclear Research and Consultancy Group12, University of Vienna13
TL;DR: The ENDF/B-VII.1 library as mentioned in this paper is the most widely used data set for nuclear data analysis and has been updated several times over the last five years. But the most recent version of the ENDF-B-VI.0 library is based on the JENDL-4.0 standard.
2,171 citations
TL;DR: In this paper, the authors present a single complete and straightforward method that reflects currently accepted practices and is consistent with existing production rate calibration measurements, which is intended to enable geoscientists, who wish to use cosmogenic-nuclide exposure age or erosion rate measurements in their work, to calculate exposure ages and erosion rates; compare previously published exposure ages on a common basis; and evaluate the sensitivity of their results to differences between published production rate scaling schemes.
1,708 citations
TL;DR: The fourth version of the Japanese Evaluated Nuclear Data Library has been produced in cooperation with the Japanese Nuclear Data Committee as mentioned in this paper, and much emphasis is placed on the improvement of the original library.
Abstract: The fourth version of the Japanese Evaluated Nuclear Data Library has been produced in cooperation with the Japanese Nuclear Data Committee. In the new library, much emphasis is placed on the impro...
1,699 citations
01 Jan 2017
TL;DR: AGILE as discussed by the authors is an ASI space mission developed with programmatic support by INAF and INFN, which includes data gathered with the 1 meter Swope and 6.5 meter Magellan Telescopes located at Las Campanas Observatory, Chile.
Abstract: This program was supported by the the Kavli Foundation, Danish National Research Foundation, the Niels Bohr International Academy, and the DARK Cosmology Centre. The UCSC group is supported in part by NSF grant AST-1518052, the Gordon & Betty Moore Foundation, the Heising-Simons Foundation, generous donations from many individuals through a UCSC Giving Day grant, and from fellowships from the Alfred P. Sloan Foundation (R.J.F.), the David and Lucile Packard Foundation (R.J.F. and E.R.) and the Niels Bohr Professorship from the DNRF (E.R.). AMB acknowledges support from a UCMEXUS-CONACYT Doctoral Fellowship. Support for this work was provided by NASA through Hubble Fellowship grants HST-HF-51348.001 (B.J.S.) and HST-HF-51373.001 (M.R.D.) awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. This paper includes data gathered with the 1 meter Swope and 6.5 meter Magellan Telescopes located at Las Campanas Observatory, Chile.r (AGILE) The AGILE Team thanks the ASI management, the technical staff at the ASI Malindi ground station, the technical support team at the ASI Space Science Data Center, and the Fucino AGILE Mission Operation Center. AGILE is an ASI space mission developed with programmatic support by INAF and INFN. We acknowledge partial support through the ASI grant No. I/028/12/2. We also thank INAF, Italian Institute of Astrophysics, and ASI, Italian Space Agency.r (ANTARES) The ANTARES Collaboration acknowledges the financial support of: Centre National de la Recherche Scientifique (CNRS), Commissariat a l'energie atomique et aux energies alternatives (CEA), Commission Europeenne (FEDER fund and Marie Curie Program), Institut Universitaire de France (IUF), IdEx program and UnivEarthS Labex program at Sorbonne Paris Cite (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02), Labex OCEVU (ANR-11-LABX-0060) and the A*MIDEX project (ANR-11-IDEX-0001-02), Region Ile-de-France (DIM-ACAV), Region Alsace (contrat CPER), Region Provence-Alpes-Cite d'Azur, Departement du Var and Ville de La Seyne-sur-Mer, France; Bundesministerium fur Bildung und Forschung (BMBF), Germany; Istituto Nazionale di Fisica Nucleare (INFN), Italy; Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO), the Netherlands; Council of the President of the Russian Federation for young scientists and leading scientific schools supporting grants, Russia; National Authority for Scientific Research (ANCS), Romania;...
1,270 citations