769 citations · 5.6k across the 83 of their papers we have counts for
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The Evolution of Helium and Hydrogen Ionization Corrections as HII Regions Age
Ruth Gruenwald, Gary Steigman, Sueli M. Viegas
Helium and hydrogen recombination lines observed in low-metallicity, extragalactic, HII regions provide the data used to infer the primordial helium mass fraction, Y_P. In deriving…
Precision Neutrino Counting
Gary Steigman
In the framework of the standard, hot big bang cosmological model the dynamics of the early evolution of the universe is controlled by the energy density of relativistic particles,…
Tracking The Baryon Density From The Big Bang To The Present
Gary Steigman
The primordial abundances of deuterium, helium, and lithium probe the baryon density of the universe only a few minutes after the Big Bang. Of these relics from the early universe,…
Stellar Mixing and the Primordial Lithium Abundance
M. H. Pinsonneault, G. Steigman, T. P. Walker +1
We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we…
CMB (And Other) Challenges To BBN
G. Steigman, J. P. Kneller, A. Zentner
Primordial nucleosynthesis provides a probe of the universal abundance of baryons when the universe was only a few minutes old. Recent observations of anisotropy in the cosmic micr…
How Does CMB + BBN Constrain New Physics?
James P. Kneller, Robert J. Scherrer, Gary Steigman +1
Recent cosmic microwave background (CMB) results from BOOMERANG, MAXIMA, and DASI provide cosmological constraints on new physics that can be competitive with those derived from Bi…