Search for: All records

ABSTRACT We run a three‐dimensional Galactic chemical evolution (GCE) model to follow the propagation of⁵³Mn (exclusively produced from type Ia supernovae, SNIa),⁶⁰Fe (exclusively produced from core‐collapse supernovae, CCSNe),¹⁸²Hf (exclusively produced from intermediate mass stars, IMSs), and²⁴⁴Pu (exclusively produced from neutron star mergers, NSMs). By comparing the predictions from our three‐dimensional GCE model to recent detections of⁵³Mn,⁶⁰Fe, and²⁴⁴Pu on the deep‐sea floor, we draw conclusions about their propagation in the interstellar medium. 

Abstract Isotope variations of nucleosynthetic origin among solar system solid samples are well documented, yet the origin of these variations is still uncertain. The observed variability of 54 Cr among materials formed in different regions of the protoplanetary disk has been attributed to variable amounts of presolar, chromium-rich oxide (chromite) grains, which exist within the meteoritic stardust inventory and most likely originated from some type of supernova explosion. To investigate if core-collapse supernovae (CCSNe) could be the site of origin of these grains, we analyze yields of CCSN models of stars with initial masses 15, 20, and 25 M ⊙ , and solar metallicity. We present an extensive abundance data set of the Cr, Mg, and Al isotopes as a function of enclosed mass. We find cases in which the explosive C ashes produce a composition in good agreement with the observed 54 Cr/ 52 Cr and 53 Cr/ 52 Cr ratios as well as the 50 Cr/ 52 Cr ratios. Taking into account that the signal at atomic mass 50 could also originate from 50 Ti, the ashes of explosive He burning also match the observed ratios. Addition of material from the He ashes (enriched in Al and Cr relative to Mg to simulate the make-up of chromite grains) to the solar system’s composition may reproduce the observed correlation between Mg and Cr anomalies, while material from the C ashes does not present significant Mg anomalies together with Cr isotopic variations. In all cases, nonradiogenic, stable Mg isotope variations dominate over the variations expected from 26 Al.