123,162 research outputs found
A multichannel front-end readout ASIC for picosecond time resolution systems based on thin UFSD
No full textThis work presents FAST, a multichannel readout ASIC designed to measure the time of arrival of MIP particles in Ultra-Fast Silicon Detectors (UFSD) with a time resolution of about 30 ps. The FAST ASIC is oriented to future High Energy Physics experiments, where high time resolution is exploited to mitigate pile-up effects, and more generally, to those applications that require accurate Time-of-Flight Silicon systems with low power consumption. The prototype has been designed in 110 nm CMOS technology, in three different flavors of front-end architecture. Each flavor is implemented in a different 20-channel ASIC. For all flavors, the power consumption of the front-end is 1.2 mW/channel. The three flavors of FAST are described in the paper, together with the simulation showing the timing performance of FAST coupled to different sensors geometries
Development of ultra fast silicon detector for 4D tracking
No full textThe Ultra Fast Silicon Detectors (UFSDs) are a new kind of silicon detectors based on Low Gain Avalanche Diodes technology. The UFSDs are optimised for time measurements with the goal of both excellent space and time resolution, which makes them a very good candidate for 4D tracking. In this paper, we will briefly explain their innovative design and show the status of the latest development. Recent measurements at the H8 beam line (CERN) will be reported, based on the UFSDs from two manufacturers: FBK and HPK. In particular, UFSDs of different thicknesses, with different doping concentrations and with different dopants of the gain layer have been studied. A time resolution of 35 ps has been achieved for a 50μm thick design and the results have been found to be in very good agreement with the expectations
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
No full textWe create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
The vanishing author in computer-generated works: a critical analysis of recent Australian case law
No full textAbstract
The use of software is ubiquitous in the creation of many copyright works, yet the requirement in copyright law that every work have a human author who engages in independent intellectual effort means that its use may prevent copyright subsistence. Several recent Australian cases have refocused attention on authorship as an essential criterion of copyright subsistence, and these cases suggest that much computer-produced output may be authorless and thus lack copyright protection. This article, the first in a two-part series, analyses how each case deals with the question of authorship of computer-produced works and why the use of software diminishes copyright protection for a significant number of computer-generated works. The article critiques the application of conventional notions of human authorship developed in the pre-computer age to modern productions and suggests alternative approaches to authorship that satisfy both the major objectives of copyright policy and the need to adapt to the computer age. The article argues that, without a broader judicial approach to authorship of computer-generated works, Parliament must remedy the lacuna in protection for these ‘authorless’ works. Possible solutions for reform are suggested. In a forthcoming article, the author comprehensively examines those reform proposals
Trench-Isolated Low Gain Avalanche Diodes (TI-LGADs)
No full textWe present a novel design of fine segmented low gain avalanche diodes (LGAD) based on trench-isolation technique. The proposed design reduces the width of the no-gain inter-pad region down to less than 10 mu m, from the 20-mu mof the current LGAD technology, enabling the production of sensors with small pixel pitch and high fill-factor. Prototypes of this new technology were produced in the FBK laboratories. Their electrical characterization in terms of I-V, gain measurement and response to a focused laser, indicates that the trenches provide electrical isolation among pixels without any increase in the dark current level and without affecting the gain of the sensor. In addition, I-V measurements of p-i-n diodes with the same trench-isolation structure demonstrate that such termination scheme can withstand more than 500 Volts without reaching breakdown. This is well above the typical operating bias voltage of LGADs, thus confirming that trench-isolation is a promising solution for finely pixelated LGAD sensors
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
High-accuracy 4D particle trackers with resistive silicon detectors (AC-LGADs)
No full textFuture particle trackers will have to measure concurrently position and time with unprecedented accuracy, aiming at 5 μm and a few 10s ps resolution respectively. A promising good candidate for such a task are the resistive AC-LGADs, solid state silicon sensors of novel design, characterized by an internal moderate gain and an AC-coupled resistive read-out to achieve signal sharing among pads. The sensor design leads to a drastic reduction in the number of read-out channels, has an intrinsic 100% fill factor, and adapts easily to any read-out geometry. This report describes the design challenges, the signal formation and recent test results obtained with the first prototypes. A part is also dedicated to the reconstruction techniques that exploit the distributed nature of the signal, including machine learning. An outlook to a future development for optimized read-out electrodes and electronics is also presented
First application of machine learning algorithms to the position reconstruction in Resistive Silicon Detectors
No full textRSDs (Resistive AC-Coupled Silicon Detectors) are n-in-p silicon sensors based on the LGAD (Low-Gain Avalanche Diode) technology, featuring a continuous gain layer over the whole sensor area. The truly innovative feature of these sensors is that the signal induced by an ionising particle is seen on several pixels, allowing the use of reconstruction techniques that combine the information from many read-out channels. In this contribution, the first application of a machine learning technique to RSD devices is presented. The spatial resolution of this technique is compared to that obtained with the standard RSD reconstruction methods that use analytical descriptions of the signal sharing mechanism. A Multi-Output regressor algorithm, trained with a combination of simulated and real data, leads to a spatial resolution of less than 2 mu m for a sensor with a 100 mu m pixel. The prospects of future improvements are also discussed
Test of Ultra Fast Silicon Detectors for Picosecond Time Measurements with a New Multipurpose Read-Out Board
No full textUltra Fast Silicon Detectors (UFSD) are sensors optimized for timing measurements employing a thin multiplication layer to increase the output signal. A multipurpose read-out board hosting a low-cost, low-power fast amplifier was designed at the University of Kansas and tested at the European Organization for Nuclear Research (CERN) using a 180 GeV pion beam. The amplifier has been designed to read out a wide range of detectors and it was optimized in this test for the UFSD output signal. In this paper we report the results of the experimental tests using 50 thick UFSD with a sensitive area of 1.4 . A timing precision below 30 ps was achieved.Ultra Fast Silicon Detectors (UFSD) are sensors optimized for timing measurements employing a thin multiplication layer to increase the output signal. A multipurpose read-out board hosting a low-cost, low-power fast amplifier was designed at the University of Kansas and tested at the European Organization for Nuclear Research (CERN) using a 180 GeV pion beam. The amplifier has been designed to read out a wide range of detectors and it was optimized in this test for the UFSD output signal. In this paper we report the results of the experimental tests using 50 µm thick UFSD with a sensitive area of 1.4mm2 . A timing precision below 30 ps was achieved
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