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Related papers: Neutron activation analysis of some Neolithic copp…

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We present new observations of copper and zinc abundances in 90 metal-poor stars, belonging to the metallicity range -3< [Fe/H] < -0.5. The present study is based on high resolution spectroscopic measurements collected at the Haute Provence…

Astrophysics · Physics 2009-11-07 T. V. Mishenina , V. V. Kovtyukh , C. Soubiran , C. Travaglio , M. Busso

Here we report on the analysis of a metallic Late Neolithic copper axe by means of Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The axe was found at Eskilstorp, south-west Scania during archaeological…

The present sample of nearby bulgelike dwarf stars has kinematics and metallicities characteristic of a probable inner disk or bulge origin. Ages derived by using isochrones give 10-11 Gyr for these stars and metallicities are in the range…

Astrophysics · Physics 2009-11-07 Luciana Pompeia , Beatriz Barbuy , Michel Grenon

By local Auger-electron spectroscopy on solid targets and accumulating screens, we studied the composition of nucleosynthesis products, in which we expected to reveal the presence of long-lived transuranium elements (LTE). In a number of…

Nuclear Experiment · Physics 2007-05-23 S. V. Adamenko , A. S. Adamenko , S. S. Ponomarev

Neutron capture cross sections are one of the most important nuclear inputs to models of stellar nucleosynthesis of the elements heavier than iron. The activation technique and the time-of-flight method are mostly used to determine the…

For the first time, we present an extensive study of stars with individual non-local thermodynamic equilibrium (NLTE) abundances for 17 chemical elements from Li to Eu in a sample of stars uniformly distributed over the $-2.62 \le$ [Fe/H]…

We investigate the non-local thermodynamic equilibrium (NLTE) analysis for \ion{Cu}{1} lines with the updated model atom that includes quantum-mechanical rate coefficients of Cu\,$+$\,H and Cu$^+$\,$+$\,H$^-$ inelastic collisions from the…

Solar and Stellar Astrophysics · Physics 2022-08-31 Xiaodong Xu , Jianrong Shi , Xiaofeng Wang

A comprehensive abundance analysis providing rare insight into the chemical history of lead stars is still lacking. We present results from high resolution (R ~ 50000), spectral analyses of three CH stars, HD 26, HD 198269, HD 224959, and,…

Solar and Stellar Astrophysics · Physics 2015-11-11 Aruna Goswami , Wako Aoki , Drisya Karinkuzhi

A beta-decay study of Cu-77 has been performed at the ISOLDE mass separator with the aim to deduce its beta-decay properties and to obtain spectroscopic information on Zn-77. Neutron-rich copper isotopes were produced by means of proton- or…

Oxygen evolution reaction (OER) electrolysis, as an important reaction involved in water splitting and rechargeable metal-air battery, has attracted increasing attention for clean energy generation and efficient energy storage. Nickel/iron…

Materials Science · Physics 2014-11-19 Ming Gong , Hongjie Dai

We report on observations of six giants in the globular cluster M15 (NGC 7078) using the Subaru Telescope to measure neutron-capture elemental abundances. Our abundance analyses based on high-quality blue spectra confirm the star-to-star…

Astrophysics · Physics 2009-11-11 Kaori Otsuki , Satoshi Honda , Wako Aoki , Toshitaka Kajino , Grant J. Mathews

We checked consistency between the copper abundance derived in six metal-poor stars using UV Cu II lines (which are assumed to form in LTE) and UV Cu I lines (treated in NLTE). Our program stars cover the atmosphere parameters which are…

Solar and Stellar Astrophysics · Physics 2018-07-25 S. A. Korotin , S. M. Andrievsky , A. V. Zhukova

The neutron-capture cross sections of 64Zn, 68Zn, and 70Zn have been measured with the activation technique in a quasistellar neutron spectrum corresponding to a thermal energy of kT = 25 keV. By a series of repeated irradiations with…

Instrumentation and Methods for Astrophysics · Physics 2013-10-08 R. Reifarth , S. Dababneh , M. Heil , F. Käppeler , R. Plag , K. Sonnabend , E. Uberseder

We study the effect of non-vanishing masses and mixings among neutrino flavours on the detection of neutrinos from stellar collapse by a water Cerenkov detector. We consider a frame-work in which there are four neutrino flavours, including…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gautam Dutta , D. Indumathi , M. V. N. Murthy , G. Rajasekaran

We present results from the first large-scale survey of neutron(n)-capture element abundances in planetary nebulae (PNe). This survey was motivated by the fact that a PN may be enriched in n-capture elements if its progenitor star…

Astrophysics · Physics 2007-08-10 N. C. Sterling , Harriet L. Dinerstein , T. R. Kallman

The sol-gel technique was developed for preparation of silica glasses doped with europium and copper chalcogenide nanoparticles. A synthesis of copper compounds proceeded within the solid matrix at the different steps of the process, and…

Mesoscale and Nanoscale Physics · Physics 2023-06-21 Valerij Gurin , Alexander Alexeenko

Neutron-capture elements, those with Z > 35, are the least well-understood in terms of nucleosynthesis and formation environments. The rapid neutron-capture, or r-process, elements are formed in the environments and/or remnants of massive…

Solar and Stellar Astrophysics · Physics 2016-06-22 Jamie C. Overbeek , Eileen D. Friel , Heather R. Jacobson

Altered and gangue quartz in hydrothermal veins from the Kubi Gold deposit in Dunkwa on Offin in the central region of Ghana are investigated for possible Au-associated indicator minerals and to provide the understanding and increase the…

Luminescence in Eu$^{2+}$ activated materials corresponds to a transition from an excited state where the lowest Eu 5$d$ level is filled with one electron (often called the (Eu$^{2+}$)$^*$ state) to the ground state with half-filled 4$f$…

Materials Science · Physics 2014-08-12 A. Chaudhry , R. Boutchko , S. Chourou , G. Zhang , N. Grønbech-Jensen , A. Canning

We compute the decay rates of emitters coupled to spheroidal nanoantennas made of gold, copper, silver, and aluminum. The spectral position of the localized surface plasmon-polariton resonance, the enhancement factors and the quantum…

Chemical Physics · Physics 2009-09-24 Ahmad Mohammadi , Vahid Sandoghdar , Mario Agio
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