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Related papers: NanoSIMS, TEM, and XANES studies of a Unique Preso…

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We report on the results of NanoSIMS isotope imaging of low-density supernova graphite grains from the Orgueil meteorite. 70 nm thick microtomed sections of three supernova graphite grains were deposited on Si wafers and isotopically imaged…

Earth and Planetary Astrophysics · Physics 2014-05-30 Evan Groopman , Thomas Bernatowicz , Ernst Zinner

We provide an overview of the isotopic signatures of presolar supernova grains, specifically focusing on 44Ti-containing grains with robustly inferred supernova origins and their implications for nucleosynthesis and mixing mechanisms in…

Solar and Stellar Astrophysics · Physics 2024-10-28 Nan Liu , Maria Lugaro , Jan Leitner , Bradley S. Meyer , Maria Schönbächler

Of the ``presolar particles'' extracted from carbonaceous chondrite dissolution residues, i.e. of those particles which show isotopic evidence of solidification in the neighborhood of other stars prior to the origin of our solar system, one…

Astrophysics · Physics 2014-10-13 P. Fraundorf , Martin Wackenhut

Presolar grains constitute remnants of stars that existed before the formation of the solar system. In addition to providing direct information on the materials from which the solar system formed, these grains provide ground-truth…

Solar and Stellar Astrophysics · Physics 2016-07-13 Pierre Haenecour , Christine Floss , Jordi Jose , Sachiko Amari , Katharina Lodders , Manavi Jadhav , Alian Wang , Frank Gyngard

We report isotopic and microstructural data on five presolar hibonite grains identified in an acid residue of the Krymka LL3.1 ordinary chondrite. Isotopic measurements by secondary ion mass spectrometry (SIMS) verified a presolar…

Solar and Stellar Astrophysics · Physics 2015-05-27 Thomas J. Zega , Conel M. O'D. Alexander , Larry R. Nittler , Rhonda M. Stroud

Graphite is one of the many presolar circumstellar condensate species found in primitive meteorites. While the isotopic compositions of low-density graphite grains indicate an origin in core-collapse supernovae, some high-density grains…

Earth and Planetary Astrophysics · Physics 2015-06-17 Manavi Jadhav , Marco Pignatari , Falk Herwig , Ernst Zinner , Roberto Gallino , Gary R. Huss

This study reports detection of rare p-process isotopes within presolar grains. Presolar grains are relic dust grains from dying stars. These microscopic dust particles are found in primitive solar system materials. Their distinct isotopic…

Presolar silicon carbide (SiC) grains in meteoritic samples can help constrain circumstellar condensation processes and conditions in C-rich stars and core-collapse supernovae. This study presents our findings on eight presolar SiC grains…

Solar and Stellar Astrophysics · Physics 2021-05-31 Sheryl A. Singerling , Nan Liu , Larry R. Nittler , Conel M. O'D. Alexander , Rhonda M. Stroud

NanoSIMS C-, N-, and O-isotopic mapping of matrix in CO3.0 chondrite Dominion Range (DOM) 08006 revealed it to have in its matrix the highest abundance of presolar O-rich grains (257 +76 / -96 ppm, 2$\sigma$) of any meteorite. It also has a…

Earth and Planetary Astrophysics · Physics 2018-03-14 Larry R. Nittler , Conel M. O'D. Alexander , Jemma Davidson , My E. I. Riebe , Rhonda M. Stroud , Jianhua Wang

Ubiquitous graphene is a stricly 2D material representing an ideal adsorbing platform due to its large specific surface area as well as its mechanical strength and resistance to both thermal and chemical stresses. However, graphene as a…

Materials Science · Physics 2016-10-06 Massimiliano Bartolomei , Giacomo Giorgi

We report the discovery of five SiC grains and one graphite grain isolated from the Murchison carbonaceous meteorite whose major-element isotopic compositions indicate an origin in nova explosions. The grains are characterized by low…

Astrophysics · Physics 2009-10-31 S. Amari , X. Gao , L. N. Nittler , E. Zinner , J. Jose , M. Hernanz , R. S. Lewis

We demonstrate an all-epitaxial and scalable growth approach to fabricate single-crystalline GaN nanowires on graphene by plasma-assisted molecular beam epitaxy. As substrate, we explore several types of epitaxial graphene layer structures…

In recent years, graphene-like boron carbide and carbon nitride nanosheets have attracted remarkable attentions, owing to their semiconducting electronic nature and outstanding mechanical and heat transport properties. Graphene-like BC6N is…

Materials Science · Physics 2021-06-15 Bohayra Mortazavi

A new formation scenario for TiC and Fe,Ni-metal inclusions in presolar graphite grains of supernova origin is described. The mineralogy and chemistry require condensation of (Fe,Ni)-titanides from Fe, Ni, and Ti-rich gaseous ejecta,…

Astrophysics · Physics 2009-11-11 Katharina Lodders

We report new O isotopic data on 41 presolar oxide grains, 38 MgAl2O4 (spinel) and 3 Al2O3 from the CM2 meteorite Murray, identified with a recently developed automated measurement system for the NanoSIMS. We have also obtained Mg-Al…

Solar and Stellar Astrophysics · Physics 2015-05-19 Frank Gyngard , Ernst Zinner , Larry R. Nittler , Alain Morgand , Frank J. Stadermann , K. Mairin Hynes

Precision control of interfacial structures and electronic properties is the key to the realization of functional heterostructures. Here, utilizing the scanning tunneling microscope (STM) both as a manipulation and characterization tool, we…

Mesoscale and Nanoscale Physics · Physics 2019-01-09 Chuanxu Ma , Zhongcan Xiao , Jingsong Huang , Liangbo Liang , Wenchang Lu , Kunlun Hong , Bobby G. Sumpter , J. Bernholc , An-Ping Li

Presolar oxide grains have been previously divided into several groups (Group 1 to 4) based on their isotopic compositions, which can be tied to several stellar sources. Much of available data was acquired on large grains, which may not be…

Solar and Stellar Astrophysics · Physics 2022-05-04 Nan Liu , Nicolas Dauphas , Sergio Cristallo , Sara Palmerini , Maurizio Busso

We report isotopic data for a total of 96 presolar oxide grains found in residues of several unequilibrated ordinary chondrite meteorites. Identified grain types include Al2O3, MgAl2O4, hibonite (CaAl12O19) and Ti oxide. This work greatly…

We report a correlated NanoSIMS-transmission electron microscopy study of the ungrouped carbonaceous chondrite Northwest Africa (NWA) 5958. We identified 10 presolar SiC grains, 2 likely presolar graphite grains, and 20 presolar silicate…

Earth and Planetary Astrophysics · Physics 2019-10-16 Larry R. Nittler , Rhonda M. Stroud , Conel M. O'D. Alexander , Kaitlin Howell

We report O, Mg-Al, Si, Ca, and Ti isotopic data for an unusual presolar oxide/silicate aggregate grain, M526-69, previously reported in the primitive ordinary chondrite Meteorite Hills 00526. The $\approx 1\mu$m aggregate consists of a Mg-…

Solar and Stellar Astrophysics · Physics 2026-05-05 Larry R. Nittler , Jens Barosch , Conel M. O'D. Alexander , Jianhua Wang
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