32,042 research outputs found
Hadronic Molecular States Composed of Spin- Singly Charmed Baryons
We investigate the possible deuteron-like molecules composed of a pair of
charmed spin- baryons, or one charmed baryon and one charmed
antibaryon within the one-boson-exchange (OBE) model. For the spin singlet and
triplet systems, we consider the couple channel effect between systems with
different orbital angular momentum. Most of the systems have binding solutions.
The couple channel effect plays a significant role in the formation of some
loosely bound states. The possible molecular states of
and might be stable once produced.Comment: 18 pages, 7 figure
Sublinear expectation linear regression
Nonlinear expectation, including sublinear expectation as its special case,
is a new and original framework of probability theory and has potential
applications in some scientific fields, especially in finance risk measure and
management. Under the nonlinear expectation framework, however, the related
statistical models and statistical inferences have not yet been well
established. The goal of this paper is to construct the sublinear expectation
regression and investigate its statistical inference. First, a sublinear
expectation linear regression is defined and its identifiability is given.
Then, based on the representation theorem of sublinear expectation and the
newly defined model, several parameter estimations and model predictions are
suggested, the asymptotic normality of estimations and the mini-max property of
predictions are obtained. Furthermore, new methods are developed to realize
variable selection for high-dimensional model. Finally, simulation studies and
a real-life example are carried out to illustrate the new models and
methodologies. All notions and methodologies developed are essentially
different from classical ones and can be thought of as a foundation for general
nonlinear expectation statistics
Electromagnetic decays of vector mesons as derived from QCD sum rules
We apply the method of QCD sum rules in the presence of external
electromagnetic fields to the problem of the electromagnetic
decays of various vector mesons, such as , and . The induced condensates obtained previously
from the study of baryon magnetic moments are adopted, thereby ensuring the
parameter-free nature of the present calculation. Further consistency is
reinforced by invoking various QCD sum rules for the meson masses. The
numerical results on the various radiative decays agree very well with the
experimental data.Comment: To appear in Phys. Lett.
Poly[tris[μ2-2-(pyrazol-1-yl)pyrazine]hexa-μ1,3-thiocyanato-tricadmium(II)]
The asymmetric unit of the title crystal structure, [Cd3(NCS)6(C7H6N4)2]n, contains two independent CdII ions, one of which is located on a crystallographic inversion center. Each independent CdII ion is in a slightly distorted octahedral coordination environment, but the disortion from ideally octahedral is greater in the environment of the CdII ion on a general position. Both thiocyanate ligands act as bridges connecting independent CdII ions, and the 2-(pyrazol-1-yl)pyrazine ligands chelate one CdII ion in a bidentate mode while the remaining N atom of the pyrazine ring coordinates to a symmetry-related CdII ion, forming a two-dimensional structure parallel to (211)
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