1,721,102 research outputs found
Characterization of a 28 nm CMOS Technology for Analog Applications in High Energy Physics
No full textIn the past few years, the 28 nm CMOS technology has raised interest in the high energy physics community for the design and implementation of readout integrated circuits for high-granularity position-sensitive detectors. This work is focused on the characterization of the 28 nm CMOS node with a particular focus on analog performance. Small-signal characteristics and behavior of the white and 1/f noise components are studied as a function of device polarity, dimensions, and bias conditions to provide guidelines for minimum noise design of front-end electronics. Comparison with data extracted from previous CMOS generations is also presented to assess the performance of the technology node under evaluation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Low-Noise Analog Channel for the Readout of the Si(Li) Detector of the GAPS Experiment
No full textThis work is focused on the design and the experimental characterization of an analog channel developed for the readout of lithium-drifted silicon detectors of the General AntiParticle Spectrometer (GAPS) experiment aimed at the search for dark matter. The instrument is designed for the identification of antideuteron particles from cosmic rays during an Antarctic balloon mission scheduled for late 2022. A low-noise analog front-end, featuring a dynamic signal compression to comply with the wide input range, has been designed in commercial 180-nm CMOS technology. The channel was fabricated in 2018 and is the first building block toward the development of a multichannel readout ASIC. The article will provide a description of the design criteria, the architecture of the channel, and a summary of the results of the experimental characterization
A Rad-Hard Bandgap Voltage Reference for High Energy Physics Experiments
No full textThis work is concerned with the characterization of a bandgap reference circuit, fabricated in a commercial 65 nm CMOS technology, designed for applications to HL-LHC experiments. Measurement results show a temperature coefficient of about 16 ppm/ C over a temperature range of 140 C (from to 100 C) and a variation of 1.6% for V from 1.08 to 1.32 V. The mean value of the bandgap output is about 400 mV, with a 5% maximum shift when exposed to a Total Ionizing Dose (TID) around 1 Grad (SiO). The power consumption is 165 W at room temperature, with a core area of 0.02835 mm
Characterization of PFM3, a 32×32 readout chip for PixFEL X-ray imager
No full textIn the framework of the PixFEL project, a readout chip for pixel sensors has been designed and fabricated in a 65 nm CMOS technology. The PixFEL detector is intended for application to coherent X-ray diffraction imaging (CXDI) at the next generation free electron lasers (FELs). This paper will present a characterization of PFM3's signal chain first stage. Characterization data has been collected from the charge sensitive amplifier (CSA) stage, implementing a dynamic compression of the input signal. Measurements demonstrating the validity of the dynamic compression feature for various gain settings (1 keV, 2keV and 3keV) and temperatures-40 °C to 70 °C are shown
Threshold tuning DACs for pixel readout chips at the High Luminosity LHC
No full textThis work is concerned with the design and the characterization of digital-to-analog current converters, developed in a 65 nm CMOS technology, conceived for threshold tuning of front-end channels at the High-Luminosity LHC experiment upgrades. Two DAC designs were integrated in a small prototype chip, that was submitted in August 2018 in the framework of the RD53 developments. One of the DAC designs features a binary weighted architecture implemented with cascoded current mirrors and no dummy transistors, whereas the second one, sharing the same architecture, exploits regular current mirrors with dummy transistors. The prototype has been tested before and after exposure to X-rays up to a TID of 460 Mrad(SiO2). The main performance parameters of the two structures, namely DAC dynamic range, INL and DNL, are compared and discussed in the paper
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