Baringer, Philip S.2014-10-202014-10-201998-06-22M. Chada et al. ((CLEO Collaboration)). (1998). "Improved measurement of the pseudoscalar decay constant fD(s)." Physical Review D, 58(3):032002. http://dx.doi.org/10.1103/PhysRevD.58.0320021550-7998https://hdl.handle.net/1808/15335This is the publisher's version also available electronically from http://journals.aps.org/prd/abstract/10.1103/PhysRevD.58.032002.We present a new determination of f(D)(s) using 5 million e(+)e(-)→cc¯ events obtained with the CLEO II detector. Our value is derived from our new measured ratio Γ(D(+)(s)→μ(+)ν)/Γ(D(+)s→φπ(+))=0.173±0.023±0.035. Using B(D(+)(s)→φπ(+))=(3.6±0.9)%, we extract f(D)(s)=(280±19±28±34) MeV. We compare this result with various model calculations.Article10.1103/PhysRevD.58.032002openAccess