4,075 research outputs found
The Rare Top Decays and
The large value of the top quark mass implies that the rare top decays and , and and
, are kinematically allowed decays so long as or , respectively. The partial decay widths for these decay modes
are calculated in the standard model. The partial widths depend sensitively on
the precise value of the top quark mass. The branching ratio for is as much as for , and could be
observable at LHC. The rare decay modes and are highly GIM-suppressed, and thus provide a means for testing the GIM
mechanism for three generations of quarks in the u, c, t sector.Comment: 19 pages, latex, t->bWZ corrected, previous literature on t->bWZ
cited, t->cWW unchange
Life-Course Differences in Occupational Mobility Between Vocationally and Generally Trained Workers in Germany
Vocational education is considered beneficial to young workers entering the labor market but disadvantageous late in their careers. Many studies assume that late-career disadvantages stem from lower levels of occupational mobility, but do not explicitly study this mechanism. This study is the first to empirically assess whether and to what extent occupational mobility differs between workers with a general education and those with vocational training and to examine how these differences develop over workers’ life courses. Using multilevel linear probability models on panel data spanning 36 years of labor market participation in Germany, we find that vocationally educated workers are less mobile, but only in the first half of their careers. In the second half, mobility rates for vocationally and generally trained workers converge. Our findings support earlier research that links vocational education to less turbulent early careers. Yet, they do not support the notion of late-career mobility disparities between workers with different types of training. Implications for research on education-based differences in career outcomes are discussed
We Found 29 Habits and Practices Adopted by Effective Fish and Wildlife Management Professionals
Radiative Tau Decays with One Pseudoscalar Meson
We have calculated the decay . We present
the photon energy spectrum, the meson-photon invariant mass spectrum and the
integrated rate as a function of a photon energy cut or an invariant mass cut.
Both the internal bremsstrahlung and the structure dependent radiation have
been taken into account. To this aim we have parametrized the form factors
and , which determine the structure dependent radiation. Observables
especially suited for the measurement of the structure dependent form factors
are found and implications on the width of the discussed.Comment: p.20, TTP93-1, LaTe
Radial Velocity along the Voyager 1 Trajectory: The Effect of Solar Cycle
As Voyager 1 and Voyager 2 are approaching the heliopause (HP)—the boundary between the solar wind (SW) and the local interstellar medium (LISM)—we expect new, unknown features of the heliospheric interface to be revealed. A seeming puzzle reported recently by Krimigis et al. concerns the unusually low, even negative, radial velocity components derived from the energetic ion distribution. Steady-state plasma models of the inner heliosheath (IHS) show that the radial velocity should not be equal to zero even at the surface of the HP. Here we demonstrate that the velocity distributions observed by Voyager 1 are consistent with time-dependent simulations of the SW-LISM interaction. In this Letter, we analyze the results from a numerical model of the large-scale heliosphere that includes solar cycle effects. Our simulations show that prolonged periods of low to negative radial velocity can exist in the IHS at substantial distances from the HP. It is also shown that Voyager 1 was more likely to observe such regions than Voyager 2
Dominant Three-Body Decays of a Heavy Higgs and Top Quark
We calculate the dominant three body Higgs decays, and , in the Standard Model. We
find that the branching ratios of these decays are of the order of few percent
for large Higgs masses. We comment on the behaviour of the partial decay width
below the threshold.
Numerical results of the following three body top decays, and , are also given. We discuss the feasibility of
observing these Higgs and top decays at future high energy colliders.Comment: 19 pages (13 Figs can be sent by request), TeX, MZ-TH/92-2
The t->WZb decay in the Standard Model: A Critical Reanalysis
We compute the t->WZb decay rate, in the Standard Model, at the leading order
in perturbation theory, with special attention to the effects of the finite
widths of the W and Z bosons. These effects are extremely important, since the
t->WZb decay occurs near its kinematical threshold. They increase the value of
the decay rate by orders of magnitude near threshold or allow it below the
nominal threshold. We discuss a procedure to take into account the finite-width
effects and compare the results with previous studies of this decay. Within the
Standard Model, for a top quark mass in the range between 170 and 180 GeV, we
find BR(t->WZb) ~ 2 x 10^{-6}, which makes the observation at the LHC very
difficult if at all possible.Comment: 10 pages, 4 eps figures, LaTeX. Few references added and minor
changes in the text. Results unchanged. Final version to appear on PL
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