ner_tags: O O O O O B-Person I-Person O O O O O O O B-Software I-Software I-Software I-Software I-Software O O O O O O O O O O O O O O O B-Person I-Person B-Person I-Person B-Person I-Person B-Person I-Person B-Person I-Person O B-Person I-Person O O O O O O O O O O O O O B-Event I-Event I-Event I-Event O B-Location O O O B-Person O B-Person O O O O O O O O B-Organization O B-Location O O O O O O B-Person O O O O B-Organization B-Fellowship I-Fellowship I-Fellowship B-Person O B-Person O O O O B-Grant I-Grant I-Grant O O B-Organization I-Organization O O B-Organization O B-Grant B-Person O O O O O O O B-Organization I-Organization I-Organization I-Organization O O B-Organization I-Organization I-Organization I-Organization B-Person O O O B-Organization O B-Grant O B-Grant I-Grant I-Grant O O B-Organization O B-Grant O B-Grant B-Grant B-Grant B-Grant B-Grant B-Grant O B-Grant O B-Organization O O O O O O O O O O B-Software B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O B-Software B-Citation I-Citation O O B-Software B-Citation I-Citation I-Citation O
tokens: ACKNOWLEDGEMENTS We are grateful to Yu Lu for making public his implementation of the Parkinson Cole merger tree algorithm. We thank the anonymous referee for constructive comments that improved the paper. We also thank Mike Grudic, Charlie Conroy, Chris McKee, Joss Bland-Hawthorn, Aldo Rodriguez-Puebla, and Rohan Naidu for helpful discussions. Ideas for this project were developed in part at the Near/Far Globular Cluster Workshop in Napa in 2017 December. KE and DRW are grateful for the hospitality provided by the MPIA in Heidelberg during the writing of this paper. KE acknowledges support from an NSF Graduate Research Fellowship. EQ and KE are supported by a Simons Investigator Award from the Simons Foundation and by NSF grant AST-1715070. DRW is supported by fellowships provided by the Alfred P. Sloan Foundation and the Alexander von Humboldt Foundation. MBK acknowledges support from NSF grant AST-1517226 and CAREER grant AST-1752913 and from NASA grants NNX17AG29G and HST-AR-13888, HST-AR-13896, HST-AR-14282, HST-AR-14554, HST-AR-15006, HST-GO-12914, and HST-GO-14191 from STScI. The analysis in this paper relied on the python packages NumPy (Van Der Walt, Colbert Varoquaux 2011 ), Matplotlib (Hunter 2007 ), and AstroPy (Astropy Collaboration 2013 ).