TY - JOUR
T1 - Cosmological constraints on superweak particles
AU - Steigman, G.
AU - Olive, K. A.
AU - Schramm, D. N.
PY - 1979
Y1 - 1979
N2 - Previous work has used the primordial abundance of He4 to infer limits on the number of neutrinos with full-strength neutral-current weak interactions. By accounting for the quark-gluon constituents of hadrons, we extend the analysis to earlier times and higher temperatures and densities and, therefore, to considerably weaker interactions. The maximum number of new, superweakly interacting, light (a MeV) particles is between ∼1 and ∼20.
AB - Previous work has used the primordial abundance of He4 to infer limits on the number of neutrinos with full-strength neutral-current weak interactions. By accounting for the quark-gluon constituents of hadrons, we extend the analysis to earlier times and higher temperatures and densities and, therefore, to considerably weaker interactions. The maximum number of new, superweakly interacting, light (a MeV) particles is between ∼1 and ∼20.
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U2 - 10.1103/PhysRevLett.43.239
DO - 10.1103/PhysRevLett.43.239
M3 - Article
AN - SCOPUS:17044398679
SN - 0031-9007
VL - 43
SP - 239
EP - 242
JO - Physical review letters
JF - Physical review letters
IS - 4
ER -