AugerPrime surface detector electronics Aglietta, M.; Allekotte, I.; Alvarez-Muñiz, J. ...
Journal of instrumentation,
10/2023, Letnik:
18, Številka:
10
Journal Article
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Abstract
Operating since 2004, the Pierre Auger Observatory has led
to major advances in our understanding of the ultra-high-energy
cosmic rays. The latest findings have revealed new insights that ...led
to the upgrade of the Observatory, with the primary goal of
obtaining information on the primary mass of the most energetic
cosmic rays on a shower-by-shower basis. In the framework of the
upgrade, called AugerPrime, the 1660 water-Cherenkov detectors of
the surface array are equipped with plastic scintillators and radio
antennas, allowing us to enhance the composition sensitivity. To
accommodate new detectors and to increase experimental capabilities,
the electronics is also upgraded. This includes better timing with
up-to-date GPS receivers, higher sampling frequency, increased
dynamic range, and more powerful local processing of the data. In
this paper, the design characteristics of the new electronics and
the enhanced dynamic range will be described. The manufacturing and
test processes will be outlined and the test results will be
discussed. The calibration of the SD detector and various
performance parameters obtained from the analysis of the first
commissioning data will also be presented.
Structural, chemical, and thermodynamic behaviours of metallic nanostructures surrounded by a variety of ceramic/refractory materials play a crucial role in their high-temperature applications. In ...this work, we report the effect of high-temperature annealing on a system of Au@SiO2 core-shell nanoparticles dispersed on Si3N4 grids. The thermal degradation of the Au–SiO2–Si3N4 system has been explained using minute compositional changes at different interfaces involving Au–SiO2, SiO2–Si3N4 and Au–Si3N4. High Angle Annular Dark Field Imaging coupled with Energy Dispersive X-ray Spectroscopy elemental mapping technique has been used for the same. Possible reactions among SiO2 and Si3N4 substrate with the aid of Au at high temperature leading to thermal decomposition of the system have been explained using High-Resolution Transmission Electron Microscopy and Selected Area Electron Diffraction analysis.
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•Study involves the effect of high temperature treatment of Au-SiO2 core shell nanoparticles dispersed on Si3N4 support film.•Thermal degradation of Au-SiO2-Si3N4 system has been explained using minute compositional changes at different interfaces.•High Angle Annular Dark Field Imaging combined with STEM-EDX elemental mapping has been used for this purpose.•Substantial thinning of the substrate material was observed around agglomerated gold nanoparticles
Near-bent functions that occur in odd dimensions are the important class of Boolean functions, which are useful functions for cryptography. In this paper, we construct near-bent function with trace ...term using well known Welch function exponent in polynomial form and various other forms of near-bent functions. We have also investigated some important cryptographical properties of near-bent functions.
ABSTRACT Here we report on the results of the Whole Earth Blazar Telescope photo-polarimetric campaign targeting the blazar S5 0716+71, organized in 2014 March to monitor the source simultaneously in ...BVRI and near-IR filters. The campaign resulted in an unprecedented data set spanning ∼110 hr of nearly continuous, multiband observations, including two sets of densely sampled polarimetric data mainly in the R filter. During the campaign, the source displayed pronounced variability with peak-to-peak variations of about 30% and "bluer-when-brighter" spectral evolution, consisting of a day-timescale modulation with superimposed hour-long microflares characterized by ∼0.1 mag flux changes. We performed an in-depth search for quasi-periodicities in the source light curve; hints for the presence of oscillations on timescales of ∼3 and ∼5 hr do not represent highly significant departures from a pure red-noise power spectrum. We observed that, at a certain configuration of the optical polarization angle (PA) relative to the PA of the innermost radio jet in the source, changes in the polarization degree (PD) led the total flux variability by about 2 hr; meanwhile, when the relative configuration of the polarization and jet angles altered, no such lag could be noted. The microflaring events, when analyzed as separate pulse emission components, were found to be characterized by a very high PD (>30%) and PAs that differed substantially from the PA of the underlying background component, or from the radio jet positional angle. We discuss the results in the general context of blazar emission and energy dissipation models.
Context. The international Whole Earth Blazar Telescope (WEBT) consortium planned and carried out three days of intensive micro-variability observations of S5 0716 + 714 from February 22, 2009 to ...February 25, 2009. This object was chosen due to its bright apparent magnitude range, its high declination, and its very large duty cycle for micro-variations. Aims. We report here on the long continuous optical micro-variability light curve of 0716+714 obtained during the multi-site observing campaign during which the Blazar showed almost constant variability over a 0.5 mag range. The resulting light curve is presented here for the first time. Observations from participating observatories were corrected for instrumental differences and combined to construct the overall smoothed light curve. Methods. Thirty-six observatories in sixteen countries participated in this continuous monitoring program and twenty of them submitted data for compilation into a continuous light curve. The light curve was analyzed using several techniques including Fourier transform, Wavelet and noise analysis techniques. Those results led us to model the light curve by attributing the variations to a series of synchrotron pulses. Results. We have interpreted the observed microvariations in this extended light curve in terms of a new model consisting of individual stochastic pulses due to cells in a turbulent jet which are energized by a passing shock and cool by means of synchrotron emission. We obtained an excellent fit to the 72-hour light curve with the synchrotron pulse model.
The Western Ghats, a hill chain of 1600 km running parallel to the west coast of India, is one of the amphibian hotspots. Gymnophiona in the Western Ghats is represented by 23 species super(1), of ...which 12 belong to Ichthyophiidae and 11 species to Caeciliidae. Under Ichthyophiidae, Ichthyophis and Uraeotyphlus are the two genera containing five and seven species respectively. In the genus Ichthyophis, two forms of species are categorized: monocoloured species and species with yellow stripes. A total of four striped caecilians, namely Ichthyophis beddomei Peters, 1879 (Karnataka, Kerala and Tamil Nadu), Ichthyophis tricolor Annandale, 1909 (Kerala), Ichthyophis longicephalus Pillai, 1986 (Kerala) and Ichthyophis kodaguensis Wilkinson, Gower, Govindappa and Venkatachalaiah, 2007 (Karnataka and Kerala), and a monocoloured species Ichthyophis bombayensis Taylor, 1960 (Gujarat, Maharashtra, Goa, Karnataka and Kerala) were described from the Western Ghats.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Setting: The three government tertiary care hospitals providing care for people living with the human immunodeficiency virus (PLHIV) in Kathmandu, Nepal.Objectives: To assess 1) the screening ...cascades for intensified case finding for tuberculosis (TB), 2) isoniazid
preventive therapy (IPT), including demographic and clinical factors associated with treatment interruption, and 3) TB infection control (IC) in the health facilities.Design: A cross-sectional study of new PLHIV enrolled from January 2012 to December 2014.Results: Among
572 registered PLHIV, 91% were on antiretroviral therapy. Of those registered, 561 (98%) were screened for TB and 73 (13%) were diagnosed with TB (17 25% sputum smear-positive, 17 25% smear-negative and 35 51% extra-pulmonary). Among the 488 (87%) PLHIV without active TB, 157 (32%) were
initiated on IPT, of whom 136 (87%) completed treatment and 17 (11%) interrupted treatment. Those who experienced adverse events were 12 times more likely to interrupt IPT. TB IC showed gaps in personal control measures and supporting structures and policies.Conclusion: The implementation
of the Three I's for collaborative TB-HIV activities in pilot sites in Nepal was successful and should be scaled up.
ABSTRACT The occurrence of low-amplitude flux variations in blazars on hourly timescales, commonly known as microvariability, is still a widely debated subject in high-energy astrophysics. Several ...competing scenarios have been proposed to explain such occurrences, including various jet plasma instabilities leading to the formation of shocks, magnetic reconnection sites, and turbulence. In this Letter, we present the results of our detailed investigation of a prominent, five-hour-long optical microflare detected during the recent WEBT campaign on 2014 March 2-6 targeting the blazar 0716+714. After separating the flaring component from the underlying base emission continuum of the blazar, we find that the microflare is highly polarized, with the polarization degree ∼(40-60)% (2-10)% and the electric vector position angle ∼(10-20)° (1-8)° slightly misaligned with respect to the position angle of the radio jet. The microflare evolution in the (Q,U) Stokes parameter space exhibits a looping behavior with a counterclockwise rotation, meaning the polarization degree decreases with the flux (but is higher in the flux decaying phase), and an approximately stable polarization angle. The overall very high polarization degree of the flare, its symmetric flux rise and decay profiles, and also its structured evolution in the Q − U plane all imply that the observed flux variation corresponds to a single emission region characterized by a highly ordered magnetic field. As discussed in the paper, a small-scale but strong shock propagating within the outflow, and compressing a disordered magnetic field component, provides a natural, though not unique, interpretation of our findings.
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