7,895 research outputs found
The Vertex in QCD Sum Rules
The form factor is evaluated in a QCD sum rule calculation for
both and off-shell mesons. We study the double Borel sum rule for
the three point function of two pseudoscalar and one vector meson current. We
find that the momentum dependence of the form factors is different if the
or the meson is off-shell, but they lead to the same coupling constant
in the vertex.Comment: 11 pages, Latex, 4 eps figure
J/psi D*D* vertex from QCD sum rules
We calculated the strong form factor and coupling constant for the vertex in a QCD sum rule calculation. We performed a double Borel sum
rule for the three point correlation function of vertex considering both
and mesons off--shell. The form factors obtained are very
different, but they give the same coupling constant.Comment: 7 pages and 4 figures, replaced version accepted for publication in
Phys. Lett.
Divisional power, intra-firm bargaining and rent-seeking behavior in multidivisional corporations
Increasing divisional operational responsibilities and the dispersal of knowledge creating activities within the firm have loosened the traditional hierarchical structure of multi-divisional firms. In this paper we argue that a similar mixture of competition and cooperation that is found in inter-firm relationships now characterizes intra-firm relationships. Our model describes a situation in which divisional managers have their own objectives that may diverge from those of the firm as a whole.Thus, divisional managers are both profit-seekers in creating value that can be appropriated and rent-seekers in attempting to maximize their divisional share of the value d by the firm. The bargaining power of a division to maintain and increase its share of the profits generated by the operations of the firm as whole is crucially determined on its strategic independence.
Electoral Participation and Communicative Voting in Europe
This paper provides an empirical investigation of electoral participation and communicative voting in 14 European countries. We estimate a multi-level voting process where individuals face a participation decision (whether to vote or abstain) and a voting decision (whether to vote strategically for a likely winner party or as communicating for a sure loser party). Our main findings can be summarized as follows. First, individuals who are either independent or uninformed are less likely to turnout. However, being both independent and uninformed does not have any statistically significant effect on electoral participation. Thus, our results question the empirical relevance of the swing voter's curse theory in large elections. Second, the probability of voting as communicating is positively related with the level of education and the degree of dissatisfaction with the political system. Finally, political preferences and institutional features characterizing the functioning of the political system and of the media market have a significant effect both on electoral participation and on the voting decision.Electoral turnout; Swing Voter's Curse; Communicative voting; Strategic voting; Multi-level qualitative choices
Spectroscopy of the All-Charm Tetraquark
We use a non-relativistic model to study the mass spectroscopy of a
tetraquark composed by quarks in the
diquark-antidiquark picture. By numerically solving the Schr\"{o}dinger
equation with a Cornell-inspired potential, we separate the four-body problem
into three two-body problems. Spin-dependent terms (spin-spin, spin-orbit and
tensor) are used to describe the splitting structure of the spectrum
and are also extended to the interaction between diquarks. Recent experimental
data on charmonium states are used to fix the parameters of the model and a
satisfactory description of the spectrum is obtained. We find that the
spin-dependent interaction is sizable in the diquark-antidiquark system,
despite of the heavy diquark mass, and that the diquark has a finite size if
treated in analogy to the systems. We find that the lowest -wave
tetraquarks might be below their thresholds of spontaneous
dissociation into low-lying charmonium pairs, while orbital and radial
excitations would be mostly above the corresponding charmonium pair threshold.
These states could be investigated in the forthcoming experiments at LHCb and
Belle II.Comment: Presented at the XVII International Conference on Hadron Spectroscopy
and Structure - Hadron2017, 25-29 September, 2017, University of Salamanca,
Salamanca, Spai
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