Related papers: Presolar Diamond in Meteorites
The rapid neutron capture or 'r process' of nucleosynthesis is believed to be responsible for the production of approximately half the natural abundance of heavy elements found on the periodic table above iron (with proton number $Z=26$)…
We use observations of heavy elements in very metal-poor stars ([Fe/H] < -2.5) in order to place constraints on the viability of collapsar models as a significant source of the r-process. We combine bipolar explosion nucleosynthesis…
The Iron Sun formed on the collapsed core of a supernova and now acts as a magnetic plasma diffuser, as did the precursor star, separating ions by mass. This process covers the solar surface with lightweight elements and with lighter…
The ratios of elemental abundances observed in metal-poor stars of the Galactic halo provide a unique present-day record of the nucleosynthesis products of its earliest stars. While the heaviest elements were synthesized by the r- and…
Cosmic rays with energies up to $10^{11}\,\mathrm{GeV}$ enter the atmosphere and produce showers of secondary particles. Inside these showers muons with high transverse momentum ($p_\mathrm{T} \gtrsim 2\,\mathrm{GeV}$) are produced from the…
With the most trans-iron elements detected of any star outside the Solar System, HD 222925 represents the most complete chemical inventory among r-process-enhanced, metal-poor stars. While the abundance pattern of the heaviest elements…
Among the short-lived radioactive nuclei inferred to be present in the early solar system via meteoritic analyses, there are several heavier than iron whose stellar origin has been poorly understood. In particular, the abundances inferred…
We study the formation of molecules and dust clusters in the ejecta of solar metallicity, Type II-P supernovae using a chemical kinetic approach. We follow the evolution of molecules and small dust cluster masses from day 100 to day 1500…
Radioactive nuclei with lifetimes on the order of millions of years can reveal the formation history of the Sun and active nucleosynthesis occurring at the time and place of its birth. Among such nuclei whose decay signatures are found in…
Following the recent abundance measurements of Mg, Al, Ca, Fe, and Ni in the black hole X-ray binary XTE J1118+480 using medium-resolution Keck II/ESI spectra of the secondary star (Gonz\'alez Hern\'andez et al. 2006), we perform a detailed…
Models of primordial and hyper-metal-poor stars with masses similar to the Sun experience an ingestion of protons into the hot core during the core helium flash phase at the end of their red giant branch evolution. This produces a…
Metal-rich asteroids and iron meteorites are considered core remnants of differentiated planetesimals and or products of oxygen-depleted accretion. Investigating the origins of iron-rich planetesimals could provide key insights into planet…
The Solar system was once rich in the short-lived radionuclide (SLR) $^{26}$Al\, but deprived in $^{60}$Fe. Several models have been proposed to explain these anomalous abundances in SLRs, but none has been set within a self-consistent…
We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium,…
The explosion of a white dwarf of mass 1.36 M$_\odot$ has been simulated in three dimensions with the aid of a SPH code. The explosion follows the delayed detonation paradigma. In this case the deflagration-detonation transition is induced…
The discovery that the short-lived radionucleide iron-60 was present in the oldest meteorites suggests that the formation of the Earth closely followed the death of a massive star. I discuss three astrophysical origins: winds from an AGB…
We calculate and discuss the chemical evolution of the isotopic silicon abundances in the interstellar medium at distances and times appropriate to the birth of the solar system. This has several objectives, some of which are related to…
A stochastic model of the chemical enrichment of metal-poor systems by core-collapse (Type II) supernovae is presented, allowing for large-scale mixing of the enriched material by turbulent motions and cloud collisions in the interstellar…
We investigate the enrichment of the pre-solar cloud core with short lived radionuclides (SLRs), especially 26Al. The homogeneity and the surprisingly small spread in the ratio 26Al/27Al observed in the overwhelming majority of…
The kilonova emission observed following the binary neutron star merger event GW170817 provided the first direct evidence for the synthesis of heavy nuclei through the r-process. The late-time transition in the spectral energy distribution…