ar X iv : h ep - e x / 01 11 02 7 v 2 2 7 N ov 2 00 1 Measurement of Natural Widths of Σ 0 c and Σ + +
نویسندگان
چکیده
In this paper we present a measurement of the natural widths of Σc and Σ ++ c . Using data from the FOCUS experiment, we find Γ(Σc) = 1.55 +0.41 −0.37 ± 0.38 MeV/c 2 and Γ(Σ c ) = 2.05 +0.41 −0.38 ± 0.38 MeV/c . The first errors are statistical, the second systematic. These results are obtained with a sample of 913 Σc → Λ + c π − decays and 1110 Σ c → Λ + c π + decays. These results are compared with recent theoretical predictions. PACS numbers: 14.20.Lq 13.30Eg The natural widths of the excited charmed baryons have become experimentally accessible [1–3] only in the last several years. The widths of most of the known excited charmed baryons are poorly determined with either no existing measurement or with an upper limit; 1 most of the lower mass excited states appear to have widths comparable to or less than the resolution of current experiments. Combined with relatively low statistics, this has made such measurements challenging. Direct measurements of the Σc widths are important since most of the current theoretical models predict the widths of charmed baryons by extrapolating from the hyperon widths. Accurate measurements of the Σc widths will enable more accurate predictions of the widths of these and other excited charm states and test the physics underlying these models. In this paper, we use data from the FOCUS experiment to obtain measure1 During final preparation of this manuscript, we became aware of a measurement of Σc and Σ ++ c intrinsic widths by the CLEO collaboration [4].
منابع مشابه
ar X iv : h ep - e x / 01 11 02 7 v 1 8 N ov 2 00 1 Measurement of Natural Widths of Σ 0 c and Σ + +
In this paper we present a measurement of the natural widths of Σc and Σ ++ c . Using data from the FOCUS experiment, we find Γ(Σc) = 1.55 +0.41 −0.37 ± 0.38 MeV/c 2 and Γ(Σ c ) = 2.05 +0.41 −0.38 ± 0.38 MeV/c . The first errors are statistical, the second systematic. These results are obtained with a sample of 913 Σc → Λ + c π − decays and 1110 Σ c → Λ + c π + decays. These results are compare...
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