355 citations · 2.3k across the 49 of their papers we have counts for
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Evidence for a chemical enrichment coupling of globular clusters and field stars in the Fornax dSph
Benjamin Hendricks, Corrado Boeche, Christian I. Johnson +4
The globular cluster H4, located in the center of the Fornax dwarf spheroidal galaxy, is crucial for understanding the formation and chemical evolution of star clusters in low-mass…
A Spectroscopic Analysis of the Galactic Globular Cluster NGC 6273 (M19)
Christian I. Johnson, R. Michael Rich, Catherine A. Pilachowski +4
A combined effort utilizing spectroscopy and photometry has revealed the existence of a new globular cluster class. These "anomalous" clusters, which we refer to as "iron-complex"…
NGC 7789: An Open Cluster Case Study
Jamie C. Overbeek, Eileen D. Friel, Heather R. Jacobson +3
We have obtained high-resolution spectra of 32 giants in the open cluster NGC 7789 using the Wisconsin-Indiana-Yale-NOAO Hydra spectrograph. We explore differences in atmospheric p…
Light-Element Abundances of Giant Stars in the Globular Cluster M71 (NGC 6838)
Maria J. Cordero, Catherine A. Pilachowski, Christian I. Johnson +1
Aluminum is the heaviest light element displaying large star--to--star variations in Galactic globular clusters (GCs). This element may provide additional insight into the origin o…
The Nature and Orbit of the Ophiuchus Stream
B. Sesar, J. Bovy, E. J. Bernard +20
The Ophiuchus stream is a recently discovered stellar tidal stream in the Milky Way. We present high-quality spectroscopic data for 14 stream member stars obtained using the Keck a…