| 1. |
- Bellm, Eric C., et al.
(författare)
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The Zwicky Transient Facility : System Overview, Performance, and First Results
- 2019
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Ingår i: Publications of the Astronomical Society of the Pacific. - : IOP Publishing. - 0004-6280 .- 1538-3873. ; 131:995
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Tidskriftsartikel (refereegranskat)abstract
- The Zwicky Transient Facility (ZTF) is a new optical time-domain survey that uses the Palomar 48 inch Schmidt telescope. A custom-built wide-field camera provides a 47 deg(2) field of view and 8 s readout time, yielding more than an order of magnitude improvement in survey speed relative to its predecessor survey, the Palomar Transient Factory. We describe the design and implementation of the camera and observing system. The ZTF data system at the Infrared Processing and Analysis Center provides near-real-time reduction to identify moving and varying objects. We outline the analysis pipelines, data products, and associated archive. Finally, we present on-sky performance analysis and first scientific results from commissioning and the early survey. ZTF's public alert stream will serve as a useful precursor for that of the Large Synoptic Survey Telescope.
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| 2. |
- Feeney, Patrick, et al.
(författare)
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Consensus statement : Eriksholm workshop on wideband absorbance measures of the middle ear
- 2013
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Ingår i: Ear and Hearing. - : Lippincott Williams & Wilkins. - 0196-0202 .- 1538-4667. ; 34:Supplement 1, s. 78s-79s
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Tidskriftsartikel (refereegranskat)abstract
- The participants in the Eriksholm Workshop on Wideband Absorbance Measures of the Middle Ear developed statements for this consensus article on the final morning of the Workshop. The presentations of the first 2 days of the Workshop motivated the discussion on that day. The article is divided into three general areas: terminology; research needs; and clinical application.The varied terminology in the area was seen as potentially confusing, and there was consensus on adopting an organizational structure that grouped the family of measures into the term wideband acoustic immittance (WAI), and dropped the term transmittance in favor of absorbance. There is clearly still a need to conduct research on WAI measurements. Several areas of research were emphasized, including the establishment of a greater WAI normative database, especially developmental norms, and more data on a variety of disorders; increased research on the temporal aspects of WAI; and methods to ensure the validity of test data. The area of clinical application will require training of clinicians in WAI technology. The clinical implementation of WAI would be facilitated by developing feature detectors for various pathologies that, for example, might combine data across ear-canal pressures or probe frequencies.
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| 3. |
- Prieve, Beth, et al.
(författare)
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Prediction of conductive hearing loss using wideband acoustic immittance
- 2013
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Ingår i: Ear and Hearing. - : Lippincott Williams & Wilkins. - 0196-0202 .- 1538-4667. ; 34:Supplement 1, s. 54s-59s
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this article was to review the effectiveness of wideband acoustic immittance (WAI) and tympanometry in detecting conductive hearing loss (CHL). Eight studies were included that measured CHL through air-and bone-conducted thresholds in at least a portion of their participants. One study included infants, three studies included children, one study included older children and adults, and three studies included adults. WAI identified CHL well in all populations. In infants and children, WAI in several single-frequency bands identified CHL with equal accuracy to measures of middle ear admittance using clinical tympanometry with a single probe tone (1000 Hz for infants; 226 Hz for children and adults). When WAI was combined across frequency bands, it identified CHL superior to traditional, single-frequency tympanometry. Only two studies used WAI tympanometry, which assesses the outer/middle ear across both frequency and introduced air pressure, and differing results were reported as to whether introducing pressure into the ear canal provides better identification of CHL. In general, WAI appears to be a promising clinical tool, and further investigation is warranted.
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| 4. |
- Stein, Robert, et al.
(författare)
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A tidal disruption event coincident with a high-energy neutrino
- 2021
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Ingår i: Nature Astronomy. - : Springer Science and Business Media LLC. - 2397-3366. ; :5, s. 510-518
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Tidskriftsartikel (refereegranskat)abstract
- Cosmic neutrinos provide a unique window into the otherwise hidden mechanism of particle acceleration in astrophysical objects. The IceCube Collaboration recently reported the likely association of one high-energy neutrino with a flare from the relativistic jet of an active galaxy pointed towards the Earth. However a combined analysis of many similar active galaxies revealed no excess from the broader population, leaving the vast majority of the cosmic neutrino flux unexplained. Here we present the likely association of a radio-emitting tidal disruption event, AT2019dsg, with a second high-energy neutrino. AT2019dsg was identified as part of our systematic search for optical counterparts to high-energy neutrinos with the Zwicky Transient Facility. The probability of finding any coincident radio-emitting tidal disruption event by chance is 0.5%, while the probability of finding one as bright in bolometric energy flux as AT2019dsg is 0.2%. Our electromagnetic observations can be explained through a multizone model, with radio analysis revealing a central engine, embedded in a UV photosphere, that powers an extended synchrotron-emitting outflow. This provides an ideal site for petaelectronvolt neutrino production. Assuming that the association is genuine, our observations suggest that tidal disruption events with mildly relativistic outflows contribute to the cosmic neutrino flux. The tidal disruption event AT2019dsg is probably associated with a high-energy neutrino, suggesting that such events can contribute to the cosmic neutrino flux. The electromagnetic emission is explained in terms of a central engine, a photosphere and an extended synchrotron-emitting outflow.
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