2,996 research outputs found

    Refined EnE_n Chern-Simons theory

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    The partition function of refined Chern-Simons theory on 3d sphere for the exceptional EnE_n gauge algebras is presented in terms of multiple sine functions. Gopakumar-Vafa (BPS) approximation is calculated and presented in the form of some refined topological string partition function.Comment: On the basis of the talk given at the workshop SQS'2

    Two-fold refinement of non simply laced Chern-Simons theories

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    Inspired by the two-parameter Macdonald-Cherednik deformation of the formulae for non simply laced simple Lie algebras, we propose a two-fold refinement of the partition function of the corresponding Chern-Simons theory on S3S^3. It is based on a two-fold refinement of the Kac-Peterson formula for the volume of the fundamental domain of the coroot lattice of non simply laced Lie algebras. We further derive explicit integral representations of the two-fold refined Chern-Simons partition functions. We also present the corresponding generalized universal-like expressions for them. With these formulae in hand, one can try to investigate a possible duality of the corresponding Chern-Simons theories with hypothetical two-fold refined topological string theories.Comment: LaTex, 8 page

    Results of Field and Laboratory Studies of Carriers and Vectors of Natural-Focal Infections on the Territory of the Republic of Armenia

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    The purpose of the study was to assess the current epizootic potential of the Transcaucasian high-mountain and Pre-Araks low-mountain natural plague foci on the territory of the Republic of Armenia using GIS technologies. Materials and methods. We used the data from an epizootiological survey, records of the abundance and species composition, spatial distribution of rodents and ectoparasites in the plague-enzootic territories of the Republic of Armenia in 2021. Results and discussion. Based on the results of the research, an electronic database of carriers and vectors of pathogens of natural-focal zoonotic infections in the plague-enzootic territories of the Republic of Armenia has been created. Applying GIS technologies, an assessment of the spatial distribution of carriers and vectors of plague has been made and areas of circulation of tularemia and leptospirosis pathogens identified. The results obtained serve as the basis for improving the efficiency of planning and carrying out preventive measures aimed at ensuring the epidemiological welfare as regards natural-focal infectious diseases in the territory of the Republic of Armenia

    Measurement of Scintillation and Ionization Yield and Scintillation Pulse Shape from Nuclear Recoils in Liquid Argon

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    We have measured the scintillation and ionization yield of recoiling nuclei in liquid argon as a function of applied electric field by exposing a dual-phase liquid argon time projection chamber (LAr-TPC) to a low energy pulsed narrow band neutron beam produced at the Notre Dame Institute for Structure and Nuclear Astrophysics. Liquid scintillation counters were arranged to detect and identify neutrons scattered in the TPC and to select the energy of the recoiling nuclei. We report measurements of the scintillation yields for nuclear recoils with energies from 10.3 to 57.3 keV and for median applied electric fields from 0 to 970 V/cm. For the ionization yields, we report measurements from 16.9 to 57.3 keV and for electric fields from 96.4 to 486 V/cm. We also report the observation of an anticorrelation between scintillation and ionization from nuclear recoils, which is similar to the anticorrelation between scintillation and ionization from electron recoils. Assuming that the energy loss partitions into excitons and ion pairs from 83m^{83m}Kr internal conversion electrons is comparable to that from 207^{207}Bi conversion electrons, we obtained the numbers of excitons (NexN_{ex}) and ion pairs (NiN_i) and their ratio (Nex/NiN_{ex}/N_i) produced by nuclear recoils from 16.9 to 57.3 keV. Motivated by arguments suggesting direction sensitivity in LAr-TPC signals due to columnar recombination, a comparison of the light and charge yield of recoils parallel and perpendicular to the applied electric field is presented for the first time.Comment: v2 to reflect published versio

    Hard Two-Photon Contribution to Elastic Lepton-Proton Scattering: Determined by the OLYMPUS Experiment

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    The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R2γR_{2\gamma}, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01~GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20°\approx 20\degree to 80°80\degree. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved GEM and MWPC detectors at 12°12\degree, as well as symmetric M{\o}ller/Bhabha calorimeters at 1.29°1.29\degree. A total integrated luminosity of 4.5~fb−1^{-1} was collected. In the extraction of R2γR_{2\gamma}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R2γR_{2\gamma}, presented here for a wide range of virtual photon polarization 0.456<ϵ<0.9780.456<\epsilon<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.Comment: 5 pages, 3 figures, 2 table
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