Hyperon Semileptonic Decays and Ckm Unitarity *
نویسنده
چکیده
We perform a new numerical analysis of hyperon semileptonic decays emphasizing the systematic uncertainties. The poor understanding of SU(3) symmetry breaking effects at second order in the vector form factor translates into a large error of |Vus|. Using our determination |Vus| = 0.226 ± 0.005 together with those coming from other sources we test the unitarity of the CKM matrix.
منابع مشابه
ar X iv : h ep - p h / 05 10 17 7 v 2 3 N ov 2 00 5 Hyperon Semileptonic Decays and CKM Unitarity ∗
We perform a new numerical analysis of hyperon semileptonic decays emphasizing the systematic uncertainties. The poor understanding of SU(3) symmetry breaking effects at second order in the vector form factor translates into a large error of |Vus|. Using our determination |Vus| = 0.226 ± 0.005 together with those coming from other sources we test the unitarity of the CKM matrix.
متن کاملSemileptonic Hyperon Decays
We review the status of hyperon semileptonic decays. The central issue is the Vus element of the CKM matrix, where we obtain Vus = 0.2250(27). This value is of similar precision, but higher, than the one derived from K l3 , and in better agreement with the unitarity requirement, |V ud | 2 + |Vus| 2 + |V ub | 2 = 1. We find that the Cabibbo model gives an excellent fit of the existing form facto...
متن کاملSemileptonic Charm Decay at a Tau Charm Factory *
The full spectrum of Df3 and Dl4 semileptonic decays can be precisely measured at a Tau Charm Factory. Sensitivety to rare semileptonic decays extends to branching fractions as small as 10m3. Improved measurements of Cabibbo-Kobayashi-Maska wa matrix elements V,, and Vcd can be obtained. With an improved theoretical understanding, semileptonic measurements can test the unitarity of the second r...
متن کاملar X iv : h ep - p h / 97 12 35 6 v 1 1 2 D ec 1 99 7 Determination of the CKM matrix by semileptonic rare B - decays ∗
The possibility to test the unitarity triangle of CKM matrix is examined by using the semileptonic rare B decays, B → Xq l l− with q = d, s and l’s are leptons. The discussion is emphasized on the CP asymmetry in the framework of standard and beyond the standard models. For the beyond standard model, a minimal extension of the standard model containing an additional isosinglet charge (-1/3) cha...
متن کاملCKM matrix : the ‘ over - consistent ’ picture of the unitarity triangle 1
In presenting an up-to-date account of the experimental knowledge of the CKM matrix, special emphasis is placed on the exceptional degree of consistency shown by the current Standard Model determination of the unitarity triangle; some implications in the question of how the theoretical nature of the dominant uncertainties affects the Standard Model predictions are discussed. Recent experimental...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2005