Related papers: Presolar Diamond in Meteorites
We present the first calculations to follow the evolution of all stable isotopes (and their abundant radioactive progenitors) in a finely zoned stellar model computed from the onset of central hydrogen burning through explosion as a Type II…
Isotope analyses on meteorites, planets, lunar samples, the solar wind, and solar flares show that heterogeneous debris of a supernova (SN) that exploded here 5 Gy ago formed the solar system. The Sun formed on the collapsed SN core. Iron…
Establishing the origin of the short-lived radionuclide (SLR) 26-Al, which was present in refractory inclusions in primitive meteorites, has profound implications for the astrophysical context of solar system formation. Recent observations…
Solar flares emit X rays and high-energy (MeV-GeV) ions (Solar Energetic Particles, or SEPs). Astronomical observations show solar mass-protostellar fluxes are a factor $\Phi \approx 3 \times 10^2 - 3 \times 10^3$ times higher than the…
Recently, models proposing superheavy particles $X$ as source of ultrahigh energy cosmic rays have attracted some interest. The $X$-particles are either metastable relic particles from the early Universe or are released by topological…
The cosmic origin of the elements heavier than iron has long been uncertain. Theoretical modelling shows that the matter that is expelled in the violent merger of two neutron stars can assemble into heavy elements such as gold and platinum…
Presolar stardust grains found in primitive meteorites are believed to retain the isotopic composition of stellar outflows at the time of grain condensation. Therefore, laboratory measurements of their isotopic ratios represent sensitive…
Solar photospheric abundances and CI-chondrite compositions are reviewed and updated to obtain representative solar system abundances of the elements and their isotopes. The new photospheric abundances obtained here lead to higher solar…
Abundances of heavier elements (barium and beyond) in many neutron-capture-element-rich halo stars accurately replicate the solar system r-process pattern. However, abundances of lighter neutron-capture elements in these stars are not…
Core-collapse supernovae are the first polluters of heavy elements in the galactic history. As such, it is important to study the nuclear compositions of their ejecta, and understand their dependence on the progenitor structure (e.g., mass,…
Transition metal sulfides (Fe, V)3S4 and (Fe, Ti)3S4, with the monoclinic Cr3S4 type structure have been studied for a long time, itinerant magnetism in form of Spin density waves (SDW) have been found in these systems with different…
The early Solar System contained short-lived radionuclides such as 60Fe (t1/2 = 1.5 Myr) whose most likely source was a nearby supernova. Previous models of Solar System formation considered a supernova shock that triggered the collapse of…
The XENON1T collaboration reported an excess of the low-energy electron recoil events between 1 and 7 keV. We explore the possibility to explain such an anomaly by the MeV-scale dark matter (DM) heated by the interior of the Sun due to the…
Analysis of bulk meteorite compositions has revealed small isotopic variations due to the presence of material (e.g., stardust) that preserved the signature of nuclear reactions occurring in specific stellar sites. The interpretation of…
The presence of short-lived radionuclides in the early solar system provides important information about the astrophysical environment in which the solar system formed. The discovery of now extinct $^{10}$Be in calcium-aluminum-rich…
We present a high-resolution spectroscopic analysis of the bright (V=11.7), extreme halo giant CS31082-001 ([Fe/H] = -2.9), obtained in an ESO-VLT Large Programme dedicated to very metal-poor stars. We find CS31082-001 to be extremely rich…
Bulk meteoritic data show isotopic variability of $slow$-neutron-capture ($s$-process) origin in a several elements heavier than Fe. One peculiar feature is that the lighter $s$-process elements (e.g., Zr and Mo) present larger anomalies…
Among presolar materials recovered in meteorites, abundant SiC and Al$_{2}$O$_{3}$ grains of AGB origins were found. They showed records of C, N, O, $^{26}$Al and s-element isotopic ratios that proved invaluable in constraining the…
Chondrules are millimeter-sized silicate spherules ubiquitous in primitive meteorites, but whose origin remains mysterious. One of the main proposed mechanisms for producing them is melting of solids in shock waves in the gaseous…
Two-dimensional simulations of mixing and fall back in non-rotating massive stars have been carried out using realistic initial models for the presupernova star and assuming standard spherically symmetric explosions of 1.2*10^51ergs. Stars…