839 citations · 5.4k across the 79 of their papers we have counts for
5 papers · 1 filter
R-process enrichment from a single event in an ancient dwarf galaxy
Alexander P. Ji, Anna Frebel, Anirudh Chiti +1
Elements heavier than zinc are synthesized through the (r)apid and (s)low neutron-capture processes. The main site of production of the r-process elements (such as europium) has be…
High-resolution spectroscopy of extremely metal-poor stars in the least evolved galaxies: Bootes II
Alexander P. Ji, Anna Frebel, Joshua D. Simon +1
We present high-resolution Magellan/MIKE spectra of the four brightest confirmed red giant stars in the ultra-faint dwarf galaxy Bootes II (Boo II). These stars all inhabit the met…
Preserving chemical signatures of primordial star formation in the first low-mass stars
Alexander P. Ji, Anna Frebel, Volker Bromm
We model early star forming regions and their chemical enrichment by Population III (Pop III) supernovae with nucleosynthetic yields featuring high [C/Fe] ratios and pair-instabili…
The Caterpillar Project: A Large Suite of Milky Way Sized Halos
Brendan F. Griffen, Alexander P. Ji, Gregory A. Dooley +4
We present the largest number of Milky Way sized dark matter halos simulated at very high mass ( M/particle) and temporal resolution (5 Myrs/snapshot) don…
SD 1313-0019 -- Another second-generation star with [Fe/H] = -5.0, observed with the Magellan Telescope
Anna Frebel, Anirudh Chiti, Alexander P. Ji +2
We present a Magellan/MIKE high-resolution (R ~ 35,000) spectrum of the ancient star SD 1313-0019 which has an iron abundance of [Fe/H] = -5.0, paired with a carbon enhancement of…