相关论文: Presolar O- and C-anomalous grains in unequilibrat…

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…

Presolar grains in meteorites and interplanetary dust particles (IDPs) carry non-solar isotopic signatures pointing to origins in supernovae, giant stars, and possibly other stellar sources. There have been suggestions that some of these…

Neutron-rich isotopes with masses near that of iron are produced in type Ia and II supernovae. Traces of such nucleosynthesis are found in primitive meteorites in the form of variations in the isotopic abundance of 54Cr, the most…

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…

Microscopic presolar grains extracted from primitive meteorites have extremely anomalous isotopic compositions revealing the stellar origin of these grains. The composition of presolar spinel grain OC2 is different from that of all other…

Isotope variations of nucleosynthetic origin among Solar System's solid samples are well documented, yet the origin of these variations is still uncertain. The observed variability of \iso{54}Cr among materials formed in different regions…

Carbon-rich grains with isotopic anomalies compared to the Sun are found in primitive meteorites. They were made by stars, and carry the original stellar nucleosynthesis signature. Silicon carbide grains of Type X and C, and low-density…

Knowledge about the age of presolar grains provides important insights into Galactic chemical evolution and the dynamics of grain formation and destruction processes in the Galaxy. Determination from the abundance of cosmic ray interaction…

Solar system materials are variably depleted in moderately volatile elements (MVEs) relative to the proto-solar composition. To address the origin of this MVE depletion, we conducted a systematic study of high-precision K isotopic…

Mainstream presolar SiC grains from primitive meteorites show a clear s-process signature in the isotopic composition of heavy trace elements. These grains most likely condensed in the winds of a variety of AGB stars. However, the non-solar…

We report combined oxygen isotope and mineral-scale trace element analyses of amoeboid olivine aggregates (AOA) and chondrules in ungrouped carbonaceous chondrite Northwest Africa 5958. The trace element geochemistry of olivine in AOA, for…

We report on isotopic and microstructural investigations of a unique presolar supernova (SN) graphite grain, referred to as G6, isolated from the Orgueil CI chondrite. G6 contains complex heterogeneities in its isotopic composition and in…

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…

Laboratory analyses on fine-grained diamond residues from primitive meteorites have shown that nano-diamonds represent the most abundant form of presolar dust preserved in meteoritic samples. The presolar diamonds carry isotopic anomalies…

Systematic variations in 54Cr/52Cr ratios between meteorite classes (Qin et al., 2010a; Trinquier et al., 2007) point to large scale spatial and/or temporal isotopic heterogeneity in the solar protoplanetary disk. Two explanations for these…

We report the H, C, and N isotopic compositions of microscale (0.2 to 2$\mu$m) organic matter in samples of asteroid Ryugu and the Orgueil CI carbonaceous chondrite. Three regolith particles of asteroid Ryugu, returned by the Hayabusa2…

A previous study (Paper I) investigated the polarization properties of a variety of simple convex grain shapes, some of which were found to be consistent with the observed polarization properties of interstellar dust from far-ultraviolet to…

Although mainstream SiC grains, the major group of presolar SiC grains found in meteorites, are believed to have originated in the expanding envelope of asymptotic giant branch (AGB) stars during their late carbon-rich phases, their Si…

We report Mo isotopic data of 27 new presolar SiC grains, including 12 14N-rich AB (14N/15N>440, AB2) and 15 mainstream (MS) grains, and their correlated Sr and Ba isotope ratios when available. Direct comparison of the data for the MS…

We report C, N, and Si isotopic data for 59 highly 13C-enriched presolar submicron- to micron-sized SiC grains from the Murchison meteorite, including eight putative nova grains (PNGs) and 29 15N-rich (14N/15N<=solar) AB grains, and their…