2,725 research outputs found

    An effectual template bank for the detection of gravitational waves from inspiralling compact binaries with generic spins

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    We report the construction of a three-dimensional template bank for the search for gravitational waves from inspiralling binaries consisting of spinning compact objects. The parameter space consists of two dimensions describing the mass parameters and one "reduced-spin" parameter, which describes the secular (non-precessing) spin effects in the waveform. The template placement is based on an efficient stochastic algorithm and makes use of the semi-analytical computation of a metric in the parameter space. We demonstrate that for "low-mass" (m1+m2≲12 M⊙m_1 + m_2 \lesssim 12\,M_\odot) binaries, this template bank achieves effective fitting factors ∼0.92\sim0.92--0.990.99 towards signals from generic spinning binaries in the advanced detector era over the entire parameter space of interest (including binary neutron stars, binary black holes, and black hole-neutron star binaries). This provides a powerful and viable method for searching for gravitational waves from generic spinning low-mass compact binaries. Under the assumption that spin magnitudes of black-holes [neutron-stars] are uniformly distributed between 0--0.98 [0 -- 0.4] and spin angles are isotropically distributed, the expected improvement in the average detection volume (at a fixed signal-to-noise-ratio threshold) of a search using this reduced-spin bank is ∼20−52%\sim20-52\%, as compared to a search using a non-spinning bank.Comment: Minor changes, version appeared in Phys. Rev.

    Detection of GRB signals with Fluorescence Detectors

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    Gamma Ray Bursts are being searched in many ground based experiments detecting the high energy component (GeV ÷\div TeV energy range) of the photon bursts. In this paper, Fluorescence Detectors are considered as possible candidate devices for these searches. It is shown that the GRB photons induce fluorescence emission of UV photons on a wide range of their spectrum. The induced fluorescence flux is dominated by GRB photons from 0.1 to about 100 MeV and, once the extinction through the atmosphere is taken into account, it is distributed over a wide angular region. This flux can be detected through a monitor of the diffuse photon flux, provided that its maximum value exceeds a threshold value, that is primarily determined by the sky brightness above the detector. The feasibility of this search and the expected rates are discussed on the basis of the current GRB observations and the existing fluorescence detectors.Comment: 16 pages 9 eps figure

    New interesting moss records from the Pollino National Park (Southern Italy).

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    Some interesting moss records in Pollino National Park, noteworthy protected area of the southern Apennines, are reported. Among them, Mnium spinosum and Brachythecium tommasinii are new to southern Italian peninsula, Grimmia laevigata, G. Montana, G. tergestina, G. trichophylla and Orthotrichum pumilum are new to Basilicata region, and, finally, Campylidium sommerfeltii is rare in southern Italy and little known in Mediterranean area

    New interesting moss records from the Pollino National Park (Southern Italy).

    Get PDF
    Some interesting moss records in Pollino National Park, noteworthy protected area of the southern Apennines, are reported. Among them, Mnium spinosum and Brachythecium tommasinii are new to southern Italian peninsula, Grimmia laevigata, G. Montana, G. tergestina, G. trichophylla and Orthotrichum pumilum are new to Basilicata region, and, finally, Campylidium sommerfeltii is rare in southern Italy and little known in Mediterranean area

    A novel Digital OTA topology with 66-dB DC Gain and 12.3-kHz Bandwidth

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    The paper introduces an enhanced digital OTA topology which allows increasing the DC gain thanks to the adoption of an inverter-based output stage. Moreover, a new equivalent small-signal model is proposed which allows to simplify the circuit analysis and paves the way to new frequency compensation strategies. Designed using a 28-nm standard CMOS technology and working at 0.3-V power supply, post-layout simulations show a 66-dB gain and a 12.3-kHz gain bandwidth product while driving a 250-pF capacitive load. As compared to other ultra-low-voltage OTAs in literature, an increase of small and large signal performance, respect to area occupation, equal to 4.6X and 1.5X, respectively, is obtained

    Detection of ultra-high energy cosmic ray showers with a single-pixel fluorescence telescope

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    We present a concept for large-area, low-cost detection of ultra-high energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Telescopes (FAST), addressing the requirements for the next generation of UHECR experiments. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. We report first results of a FAST prototype installed at the Telescope Array site, consisting of a single 200 mm photomultiplier tube at the focal plane of a 1 m2^2 Fresnel lens system taken from the prototype of the JEM-EUSO experiment. The FAST prototype took data for 19 nights, demonstrating remarkable operational stability. We detected laser shots at distances of several kilometres as well as 16 highly significant UHECR shower candidates.Comment: Accepted for publication in Astroparticle Physic

    Post-graduate medical education in public health: The case of Italy and a call for action

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    Public health technical expertise is of crucial importance to inform decision makers\u2019 action in the field of health and its broader determinants. Improving education and training of public health professionals for both practice and research is the starting point to strengthen the role of public health so that current health challenges can be efficiently tackled. At the Association of Schools of Public Health in the European Region (ASPHER) Deans\u2019 & Directors\u2019 2017 Annual Retreat, we presented the structure and management of public health training system in Italy, and we reported recent data on Italian public health specialists\u2019 educational experience, employment opportunities and job satisfaction. Public health training in Italy is implemented in the context of the post-graduate medical education residency programme in Hygiene and Preventive Medicine, delivered by 34 University-based Schools of Public Health. We report relatively high employment rates across the county and wide spectrum of career opportunities for young public health specialists. However, job security is low and training expectations only partially met. We call upon other Schools of Public Health to scale up the survey within the broad ASPHER community in a shared and coordinated action of systematically collecting useful data that can inform the development of public health education and training models, their implementation and fruitful interaction with population health, health systems and services

    Visual Attention for Region of Interest Coding in JPEG 2000

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    This paper details work undertaken on the application of an algorithm for visual attention (VA) to region of interest (ROI) coding in JPEG 2000 (JP2K). In this way, an "interest ordered" progressive bit-stream is produced where the regions highlighted by the VA algorithm are presented first in bit-stream. The paper briefly outlines the terminology used in JP2K, the packet structure of the bit-stream, and the methods available to achieve ROI coding in JP2K (tiling, coefficient scaling, and code-block selection). The paper then describes how the output of the VA algorithm is post-processed so that an ROI is produced that can be efficiently coded using coefficient scaling in JP2K. Finally, a two alternative forced choice (2AFC) visual trial is undertaken to compare the visual quality of images encoded using the proposed VA ROI algorithm and conventional JP2K. The experimental results show that, while there is no overall preference for the VA ROI encoded images; there is an improvement in perceived image quality at low bit rates (below 0.25 bits per pixel). It is concluded that an overall increase in image quality only occurs when the increase in quality of the ROI more than compensates for the decrease in quality of the image background (i.e., non-ROI)
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