424 research outputs found
Vertex operator algebras of rank 2 - the Mathur-Mukhi-Sen theorem revisited
Let be a strongly regular vertex operator algebra and let be the space spanned by the characters of the irreducible -modules.\ It is known that is the space of solutions of a so-called \emph{modular linear differential equation (MLDE)}.\ In this paper we obtain a near-classification of those for which the corresponding MLDE is irreducible and monic of order .\ As a consequence we derive the complete classification when has exactly two simple modules.\ It turns out that is either one of four affine Kac-Moody algebras of level , or the Yang-Lee Virasoro model of central charge .\ Our proof establishes new connections between the characters of and Gauss hypergeometric series, and puts the finishing touches to work of Mathur, Mukhi and Sen who first considered this problem forty years ago
Study of fast electron generation using multi beam of LFEX-class laser
Fast Ignition Realization Experiment project phase-I (FIREX-I) is being performed at Institute of Laser Engineering, Osaka University. In this project, the four-beam bundled high-energy Petawatt laser (LFEX) is being operated. LFEX laser provides great multi-beam irradiation flexibility, with the possibility of arrange the pulses in temporal sequence, spatially separate them in distinct spots of focus them in a single spot. In this paper, we study the two-beam interference effects on high-intensity picosecond laser-plasma interaction (LPI) by two-dimensional relativistic Particle-In-Cell simulations. The interference causes surface perturbation, which enhances laser absorption and underdense plasma generation, increasing the accelerated electron number and their slope temperature. The laser-to-electron energy conversion efficiency for two-beam interference case is suitable for Fast Ignition (FI) compared to the single beam case, but the increment of fast electron divergence leads to lower energy coupling. To optimize the target design for FI, these interference effects should be taken into consideration
Research on Ablation Process of Liquid Wall of Laser Fusion Reactor by Back-side Irradiation with Laser
The tensor structure on the representation category of the triplet algebra
We study the braided monoidal structure that the fusion product induces on
the abelian category -mod, the category of representations of
the triplet -algebra . The -algebras are a
family of vertex operator algebras that form the simplest known examples of
symmetry algebras of logarithmic conformal field theories. We formalise the
methods for computing fusion products, developed by Nahm, Gaberdiel and Kausch,
that are widely used in the physics literature and illustrate a systematic
approach to calculating fusion products in non-semi-simple representation
categories. We apply these methods to the braided monoidal structure of
-mod, previously constructed by Huang, Lepowsky and Zhang, to
prove that this braided monoidal structure is rigid. The rigidity of
-mod allows us to prove explicit formulae for the fusion product
on the set of all simple and all projective -modules, which were
first conjectured by Fuchs, Hwang, Semikhatov and Tipunin; and Gaberdiel and
Runkel.Comment: 58 pages; edit: added references and revisions according to referee
reports. Version to appear on J. Phys.
Test of the Conserved Vector Current Hypothesis by beta-ray Angular Distribution Measurement in the Mass-8 System
The beta-ray angular correlations for the spin alignments of 8Li and 8B have
been observed in order to test the conserved vector current (CVC) hypothesis.
The alignment correlation terms were combined with the known beta-alpha-angular
correlation terms to determine all the matrix elements contributing to the
correlation terms. The weak magnetism term, 7.5\pm0.2, deduced from the
beta-ray correlation terms was consistent with the CVC prediction 7.3\pm0.2,
deduced from the analog-gamma-decay measurement based on the CVC hypothesis.
However, there was no consistent CVC prediction for the second-forbidden term
associated with the weak vector current. The experimental value for the
second-forbidden term was 1.0 \pm 0.3, while the CVC prediction was 0.1 \pm 0.4
or 2.1 \pm 0.5.Comment: 31 pages, 12 figures, Accepted for publication in Phys. Rev.
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