ner_tags: O O O B-Person I-Person B-Person I-Person B-Person I-Person B-Person I-Person I-Person B-Person I-Person B-Person I-Person I-Person O B-Person I-Person O O O B-Person O B-Person O O O O O O B-Grant I-Grant I-Grant I-Grant I-Grant B-Grant O O O B-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant B-Grant O B-Person O O O O O O B-Fellowship I-Fellowship I-Fellowship O O B-Fellowship I-Fellowship I-Fellowship I-Fellowship I-Fellowship I-Fellowship I-Fellowship I-Fellowship B-Person O O O O O O O B-Person I-Person I-Person I-Person I-Person
tokens: The authors thank K. Bowen, P.-M. Hillenbrand, J. Liévin, D. C. Lis, O. Novotný, I. R. Sims, and A. Viggiano for stimulating discussions. D.W.S. and R.G.B. were supported in part by the NASA Astrophysics Research and Analysis (APRA) program and the NSF Division of Astronomical Sciences Astronomy and Astrophysics Grants (AAG) program. S.V. was supported in part by a Barry Goldwater Scholarship and the USRA James B. Willett Educational Memorial Scholarship Award. X.U. is a Senior Research Associate of the Fonds de la Recherche Scientifique-FNRS.