4,359 research outputs found
Production rates for hadrons, pentaquarks and , and di-baryon in relativistic heavy ion collisions by a quark combination model
The hadron production in relativistic heavy ion collisions is well described
by the quark combination model. The mixed ratios for various hadrons and the
transverse momentum spectra for long-life hadrons are predicted and agree with
recent RHIC data. The production rates for the pentaquarks , and the di-baryon are estimated, neglecting
the effect from the transition amplitude for constituent quarks to form an
exotic state.Comment: The difference between our model and other combination models is
clarified. The scaled transverse momentum spectra for pions, kaons and
protoms at both 130 AGeV and 200 AGeV are given, replacing the previous
results in transverse momentum spectr
Optically and Chemically Controllable Light Flow in Topological Plasmonic Waveguides Based on Graphene Metasurfaces
In this work, topologically-protected plasmon transport is demonstrated in graphene-based plasmonic crystal waveguides, the main ideas being subsequently applied to optically and chemically controllable nanodevices. In two configurations of topological graphene metasurfaces created by breaking their inversion symmetry, symmetry-protected Dirac cones associated to the underlying metasurfaces are gapped out, which leads to the formation of topological valley modes inside the nontrivial bandgap. The propagation of the corresponding topological modes shows unidirectional characteristics in both cases. Based on the proposed plasmonic topological waveguides, an active optical nanoswitch and a gas molecular sensor are designed by optically and chemically tuning the frequency dispersion of graphene metasurfaces via Kerr effect and gas molecular absorption, respectively. Specifically, the variation of the frequency dispersion of graphene can switch the topological mode into the region of leaky bulk modes, resulting in a dramatic variation of the plasmon transmission. Our work may contribute to the development of new ultracompact and ultrafast active photonic nanodevices based on graphene
Multicystic Changes of Juvenile Nasopharyngeal Angiofibroma: The First Case Report in the Literature
Multicystic changes of juvenile nasopharyngeal angiofibroma: the first case report in the literature. Otolaryngologists, pathologists, and radiologists had better pay attention to this infrequent incidence
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