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Sample records for hf rms detector

  1. A digitally calibrated CMOS RMS power detector for RF automatic gain control

    Institute of Scientific and Technical Information of China (English)

    Yan Taotao; Wang Hui; Li Jinbo; Zhou Jianjun

    2013-01-01

    This paper presents the design and implementation of a digitally calibrated CMOS wideband radio frequency (RF) root-mean-square (RMS) power detector for high accuracy RF automatic gain control (AGC).The proposed RMS power detector demonstrates accurate power detection in the presence of process,supply voltage,and temperature (PVT) variations by employing a digital calibration scheme.It also consumes low power and occupies a small chip area.The measurement results show that the scheme improves the accuracy of the detector to better than 0.3 dB over the PVT variations and wide operating frequency range from 0.2 to 0.8 GHz.Implemented in a 0.18 μm CMOS process and occupying a small die area of 263 × 214 μm2,the proposed digitally calibrated CMOS RMS power detector only consumes 1.6 mA in power detection mode and 2.1 mA in digital calibration mode from a 1.8 V supply voltage.

  2. Ride Motion Simulator (RMS)

    Data.gov (United States)

    Federal Laboratory Consortium — The RMS is a simulator designed for crew station and man-in-the-loop experimentation. The simulator immerses users in a synthetic battlefield to experience realistic...

  3. Remote Minehunting System (RMS)

    Science.gov (United States)

    2013-12-01

    Activity BY - Base Year DAMIR - Defense Acquisition Management Information Retrieval Dev Est - Development Estimate DoD - Department of Defense DSN - Defense...Milestones SAR Baseline Dev Est Current APB Development Objective/Threshold Current Estimate Milestone II DEC 1999 DEC 1999 JUN 2000 DEC 1999 OA...updated and will be re-assessed for MS C to align RMS with the LCS MCM MP IOT &E in September 2015. Acronyms and Abbreviations DOT&E - Director

  4. Monitoring of Radiation Damage of Quartz Fibers in the Hf-Cms Detector

    Science.gov (United States)

    Merlo, Jean-Pierre

    2014-06-01

    Two HF calorimeters are in the range 3 monitors this loss and is used to correct energies. Since 2010, 29 fb-1 were accumulated and "Raddam runs" were taken in beam stops. The raddam data are compared to our light transmission measurements of irradiated fibers. A FLUKA simulation of dose at 14 TeV for a luminosity accumulated of 3000 fb-1 is presented.

  5. HF radiation emitted by chaotic leader processes

    Science.gov (United States)

    Mäkelä, J. S.; Edirisinghe, M.; Fernando, M.; Montaño, R.; Cooray, V.

    2007-04-01

    This paper presents direct measurements of narrowband 10 MHz HF radiation from so-called “chaotic leaders” associated with subsequent return strokes. Although the term is controversial and poorly defined, we find that more than 30% of subsequent strokes in close lightning flashes contain electric field characteristics that are best described as “chaotic”. In earlier studies, return strokes have consistently been observed to be the strongest sources of HF radiation, but the results for leader processes are less consistent. We also observe return strokes to be the main HF emitter, and the leaders before the first return stroke in a flash sequence also emit HF though somewhat less intensely. The leaders preceding subsequent strokes typically emit little or no HF radiation, whether they are dart or dart-stepped leaders. However, it was observed that the presence of a chaotic component increases the leader HF intensity dramatically Defining the HF intensity unequivocally can be problematic for processes like chaotic leaders which have a combination of continuous and impulsive phenomena. Two time-domain methods were used to measure the HF intensity, the peak energy and the RMS energy. In the frequency domain these correspond to the energy spectral density (ESD) and power spectral density (PSD), respectively. It was found that the methods are not necessarily compatible. Thus, it is suggested that to clarify future work, leader processes should be characterized by the PSD rather than the ESD.

  6. The resupply interface mechanism RMS compatibility test

    Science.gov (United States)

    Jackson, Stewart W.; Gallo, Frank G.

    1990-01-01

    Spacecraft on-orbit servicing consists of exchanging components such as payloads, orbital replacement units (ORUs), and consumables. To accomplish the exchange of consumables, the receiving vehicle must mate to the supplier vehicle. Mating can be accomplished by a variety of docking procedures. However, these docking schemes are mission dependent and can vary from shuttle bay berthing to autonomous rendezvous and docking. Satisfying the many docking conditions will require use of an innovative docking device. The device must provide fluid, electrical, pneumatic and data transfer between vehicles. Also, the proper stiffness must be obtained and sustained between the vehicles. A device to accomplish this, the resupply interface mechanism (RIM), was developed. The RIM is a unique device because it grasps the mating vehicle, draws the two vehicles together, simultaneously mates all connectors, and rigidizes the mating devices. The NASA-Johnson Manipulator Development Facility was used to study how compatible the RIM is to on orbit docking and berthing. The facility contains a shuttle cargo bay mockup with a remote manipulator system (RMS). This RMS is used to prepare crew members for shuttle missions involving spacecraft berthing operations. The MDF proved to be an excellant system for testing the RIM/RMS compatibility. The elements examined during the RIM JSC test were: RIM gross and fine alignment; berthing method sequence; visual cuing aids; utility connections; and RIM overall performance. The results showed that the RIM is a good device for spacecraft berthing operations. Mating was accomplished during every test run and all test operators (crew members) felt that the RIM is an effective device. The purpose of the JSC RIM test and its results are discussed.

  7. RMS slope of exponentially correlated surface roughness for radar applications

    DEFF Research Database (Denmark)

    Dierking, Wolfgang

    2000-01-01

    In radar signature analysis, the root mean square (RMS) surface slope is utilized to assess the relative contribution of multiple scattering effects. For an exponentially correlated surface, an effective RMS slope can be determined by truncating the high frequency tail of the roughness spectrum...

  8. Financing development stage biotechnology companies: RMs vs. IPOs.

    Science.gov (United States)

    Ahn, Mark J; Couch, Robert B; Wu, Wei

    2011-01-01

    We examine reverse mergers (RMs) in the biotechnology industry and find that, when compared to initial public offerings (IPOs), RMs are smaller, have significantly lower market valuations relative to size, and generally invest less. We also find that RMs exhibit positive abnormal returns on the announcement date and throughout the first year after the RM event. In looking at liquidity measures, we find that RMs tend to be less liquid than IPOs and that illiquidity is greater during the six-month lock-up period following the RM event. Thus, RMs may be an appropriate alternative financing vehicle in capital intensive, high-risk biotechnology companies which require accessing deeper and larger pools of investors in public capital markets across multiple milestone periods in a "pay for progress" environment.

  9. RMS Pictorial Scale (RMS-PS: An innovative scale for the assessment of child′s dental anxiety

    Directory of Open Access Journals (Sweden)

    R M Shetty

    2015-01-01

    Full Text Available Background: Dental anxiety assessment for young children is as important as performing their treatment. Appropriate knowledge of patient′s anxiety boosts confidence and will help us to review potential management options specific to every child. Aim: This study aimed to validate (RMS Pictorial Scale (RMS-PS and to compare it with Venham Picture Test (VPT and Facial image scale (FIS in measuring dental anxiety for young children during their first dental visit. Materials and Methods: A total of 102 healthy children aged between 4 and 14 years during their first dental visit were randomly selected for the study. Childs anxiety level was measured using three different scales namely (i RMS-PS (ii VPT, and (iii FIS. Statistical Analysis: Student t test was used to compare the scores obtained from all the three scales. Pearson correlation test was used to obtain correlation among the scales used in the study. Results: A strong correlation (0·76 was found between the VPT and RMS-PS, and a moderate correlation (0.5 was found between RMS-PS and FIS, indicating good validity for the RMS-PS. Conclusions: The findings of this study suggest that the RMS-PS can be a newer and easiest means for the assessment of dental anxiety for young children in a clinical context.

  10. Incorporating Skew into RMS Surface Roughness Probability Distribution

    Science.gov (United States)

    Stahl, Mark T.; Stahl, H. Philip.

    2013-01-01

    The standard treatment of RMS surface roughness data is the application of a Gaussian probability distribution. This handling of surface roughness ignores the skew present in the surface and overestimates the most probable RMS of the surface, the mode. Using experimental data we confirm the Gaussian distribution overestimates the mode and application of an asymmetric distribution provides a better fit. Implementing the proposed asymmetric distribution into the optical manufacturing process would reduce the polishing time required to meet surface roughness specifications.

  11. ExtraHF survey

    DEFF Research Database (Denmark)

    Piepoli, Massimo F; Binno, Simone; Corrà, Ugo

    2015-01-01

    AIMS: In heart failure (HF), exercise training programmes (ETPs) are a well-recognized intervention to improve symptoms, but are still poorly implemented. The Heart Failure Association promoted a survey to investigate whether and how cardiac centres in Europe are using ETPs in their HF patients...... of evidence on safety or benefit was cited. When implemented, an ETP was proposed to all HF patients in only 55% of the centres, with restriction according to severity or aetiology. CONCLUSIONS: With respect to previous surveys, there is evidence of increased availability of ETPs in HF in Europe, although too...

  12. Combining Performance and Flexibility for RMS with a Hybrid Architecture

    NARCIS (Netherlands)

    Arjan van Zanten; Dick van der Steen; Dennis Koole; Ing. Erik Puik; Patrick Wit; Pascal Muller; Leo van Moergestel; Arjan Groenewegen; John-Jules Meyer; Daniël Telgen

    2013-01-01

    Author supplied Combining Performance and Flexibility for RMS with a Hybrid Architecture Dani¨el Telgen 12? , Leo van Moergestel 1 , Erik Puik 1 , Pascal Muller 1 , Arjan Groenewegen 1 , Dick van der Steen 1 , Dennis Koole 1 , Patrick de Wit 1 , Arjen van Zanten 1 , and John-Jules

  13. Combining Performance and Flexibility for RMS with a Hybrid Architecture

    NARCIS (Netherlands)

    Telgen, Daniël; Moergestel, Leo van; Puik, Erik; Muller, Pascal; Groenewegen, Arjan; Steen, Dick van der; Koole, Dennis; Wit, Patrick; Zanten, Arjan van; Meyer, John-Jules

    2013-01-01

    Author supplied Combining Performance and Flexibility for RMS with a Hybrid Architecture Dani¨el Telgen 12? , Leo van Moergestel 1 , Erik Puik 1 , Pascal Muller 1 , Arjan Groenewegen 1 , Dick van der Steen 1 , Dennis Koole 1 , Patrick de Wit 1 , Arjen van Zanten 1 , and John-Jules Meyer 2 1 Departm

  14. NIF optical specifications - the importance of the RMS gradient specification

    Energy Technology Data Exchange (ETDEWEB)

    Auerbach, J M; Cotton, C T; English, R E; Henesian, M A; Hunt J T; Kelly, J H; Lawson, J K; Sacks, J B; Shoup, M J; Trenholme, W H

    1998-07-06

    The performance of the National Ignition Facility (NIF), especially in terms of laser focusability, will be determined by several key factors. One of these key factors is the optical specification for the thousands of large aperture optics that will comprise the 192 beamlines. We have previously reported on the importance of the specification of the power spectral density (PSD) on NIF performance. Recently, we have been studying the importance of long spatial wavelength (>33 mm) phase errors on focusability. We have concluded that the preferred metric for determining the impact of these long spatial wavelength phase errors is the rms phase gradient. In this paper, we outline the overall approach to NIF optical specifications, detail the impact of the rms phase gradient on NIF focusability, discuss its trade-off with the PSD in determining the spot size and review measurements of optics similar to those to be manufactured for NIF.

  15. A General Survey for RMs development in China

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ The basic concept of RMs According to GB/T 15000.1-94 Directives for the work of reference materials (1) General rules for description of reference materials in technical standards, when the analysis and test method defined in the technical standards need using RM (ref erence material) to assure the application effect in different time and area, the relevant RM should be developed and used. This shows that RM is a kind of practical standards, the necessary complement of technical document standards and a part of standardization work.

  16. Singapore rhabdomyosarcoma (RMS) experience: shall we change our practice?

    Science.gov (United States)

    Aung, Lele; Soe, Tin Aung; Chang, Kenneth Te; Quah, Thuan Chong

    2014-02-01

    Although rhabdomyosarcoma (RMS) constitutes nearly 4% of all children diagnosed with cancer in the ethnically diverse small island city of Singapore, it is unknown how children with RMS fare. This study investigated 50 children with RMS from April 1993 to December 2010 from KK Women's and Children's Hospital (KKH) and National University Hospital (NUH). They were treated either as per Intergroup Rhabdomyosarcoma Study Group (IRSG) or Société Internationale Pediatrique D'Oncologie (SIOP) regimens. Median age of diagnosis was 5.1 years (range, 0.1 to 17.3 years) with a median follow-up of 3.3 years (range, 0.4 to 15.6 years). According to IRSG classifi cation, 18 (36%) were staged as low-risk (LR); 19 (38%) were intermediate-risk (IR), 12 (24%) were high-risk (HR) and it was unknown in 1 patient. Twenty-nine (58%) were of embryonal subtype, 17 (34%) were alveolar and subclassification was not available in 4. The primary sites of tumour were: head and neck region (n = 22); genitourinary (n = 19); extremity (n = 10); and abdomen/retroperitoneal (n = 5). At the time of analysis, 80% were alive with no evidence of disease, 9 were dead of disease, and 2 were alive with disease. By disease risk group, the 5-year event-free survival (EFS) for LR group disease was 81.3% (95% CI, 62.0 to 100.0), IR group was 61.4% (95% CI, 32.3 to 90.4) and HR group was 25.0% (95% CI, 0.0 to 49.5) respectively (P HR 0.0% vs 42.9% (P = 0.336) respectively. Of 15 relapses (HR, n = 7), at median of 2 years, 4 of 6 patients treated as per SIOP regimen were dead of disease and 3 of 8 treated as per IRSG were alive. Radiation therapy (RT) can be avoided in LR classification although those in higher risk classification need RT to local and distant metastatic disease. The outcome of children with RMS in Singapore can be further improved by coming together as a cooperative group to provide the best total care. Improved communication, multidisciplinary team collaboration, standardisation of protocols

  17. Frederiksberg HF kursus

    DEFF Research Database (Denmark)

    Lindstrøm, Maria Duclos

    2008-01-01

    Notatet bygger på et interviewmateriale med dimitterede HF-kursister 3 måneder efter endt eksamen. Notatet undersøger dels, hvad der har hjulpet til at gennemføre, dels hvad der har været negativt og vanskeligt ved uddannelsen. Endvidere belyser notatet hvad kursisterne oplever at tage med fra de...

  18. Optimization of Classical Hydraulic Engine Mounts Based on RMS Method

    Directory of Open Access Journals (Sweden)

    J. Christopherson

    2005-01-01

    Full Text Available Based on RMS averaging of the frequency response functions of the absolute acceleration and relative displacement transmissibility, optimal parameters describing the hydraulic engine mount are determined to explain the internal mount geometry. More specifically, it is shown that a line of minima exists to define a relationship between the absolute acceleration and relative displacement transmissibility of a sprung mass using a hydraulic mount as a means of suspension. This line of minima is used to determine several optimal systems developed on the basis of different clearance requirements, hence different relative displacement requirements, and compare them by means of their respective acceleration and displacement transmissibility functions. In addition, the transient response of the mount to a step input is also investigated to show the effects of the optimization upon the time domain response of the hydraulic mount.

  19. A torsional sensor for MEMS-based RMS voltage measurements

    Directory of Open Access Journals (Sweden)

    J. Dittmer

    2008-05-01

    Full Text Available RF voltage measurement based on electrostatic RMS voltage-to-force conversion is an alternative method in comparison to the conventional thermal power dissipation method. It is based on a mechanical force induced by an RF voltage applied to a micro-mechanical system. For a theoretically adequate resolution and high precision measurements, the necessary geometrical dimensions of the sensor require the application of micro machining. In this contribution, the dependence between electrical and geometrical properties of different sensor designs is investigated. Based on these results, problems related to practical micro-machining and solutions with respect to possible sensor realizations are discussed. The evolution of different sensor generations is shown.

  20. The first HF table, after heat treatment and ready to be machined in HEPCO, Arak (IRAN)

    CERN Multimedia

    Tiziano Camporesi

    2003-01-01

    The first HF support table 'load' tested by the team of people who have contributed to it from design to welding. This table will support the 240 tons of 1 HF detector and will integrate the raisers which will push it up to the beam line level. It is the first Iranian contribution to an HEP experiment.

  1. Static and dynamic aspects of the rms local slope of growing random surfaces

    NARCIS (Netherlands)

    Palasantzas, George

    1997-01-01

    In this work, we investigated static and dynamic aspects of the rms local surface slope ‘‘ρ’’ for self-affine random surfaces. The rms local slope is expressed as a function of the rms roughness amplitude σ, the in-plane correlation length ξ, and the roughness exponent H (0 0).

  2. RMS Current of a Photovoltaic Generator in Grid-Connected PV Systems: Definition and Application

    Directory of Open Access Journals (Sweden)

    P. J. Pérez

    2008-01-01

    Full Text Available This paper includes a definition of a new and original concept in the photovoltaic field, RMS current of a photovoltaic generator for grid-connected systems. The RMS current is very useful for calculating energy losses in cables used in a PV generator. As well, a current factor has been defined in order to simplify RMS current calculation. This factor provides an immediate (quick and easy calculation method for the RMS current that does not depend on the case particular conditions (orientation, location, etc.. RMS current and current factor values have been calculated for different locations and modules.

  3. Extratropical transitioning in the RMS Japan typhoon wind field model

    Science.gov (United States)

    Loridan, Thomas; Scherer, Emilie; Khare, Shree

    2013-04-01

    Given its meridional extent and location within the Pacific basin, Japan is regularly impacted by strong winds from cyclones at different stages of their lifecycle. To quantify the associated risk of damage to properties, catastrophe models such as the ones developed by RMS aim to simulate wind fields from thousands of stochastic storms that extrapolate historical events. In a recent study using 25 years of reanalysis data, Kitabatake (2011) estimated that 40 % of all Pacific tropical cyclones completed their transition as an extra tropical system. From a cat modelling point of view it is the increase in wind field asymmetry observed during these transitioning episodes that is critical, with examples like typhoon Tokage in 2004 showing the potential for damaging gusts on both sides of the storm track. In this context a compromise has to be found between the need for complex numerical models able to simulate wind field variability around the cyclone during its entire evolution, and obvious running time constrains. The RMS wind field model is based on an optimized version of the Willoughby parametric profile (Willoughby et al., 2006) which requires calibration against targets representative of cyclone wind fields throughout their lifecycle. We here present the different sources of data involved in the development of this model. This includes (1) satellite products to characterize wind fields from fully tropical storms, (2) high resolution simulations of key transitioning events using the WRF mesoscale model to complement the database at other stages (i.e. for transitioning and fully extra tropical wind fields), and (3) reanalysis data which can be used with Hart (2003)'s cyclone phase space methodology to provide an estimate of the mean duration of transitioning episodes in the Pacific. Kitabatake, N., 2011: Climatology of extratropical transition of tropical cyclones in the Western North Pacific defined by using cyclone phase space. J. Meteor. Soc. Japan, 89, 309

  4. The RMS Survey: Galactic distribution of massive star formation

    CERN Document Server

    Urquhart, J S; T., T J; Moore,; Hoare, M G; Lumsden, S L; Mottram, J C; Thompson, M A; Oudmaijer, R D

    2013-01-01

    Abridged: We have used the well-selected sample of ~1750 embedded, young, massive stars identified by the RMS survey to investigate the Galactic distribution of recent massive star formation. We describe the various methods used to assign distances extracted from the literature, and solve the distance ambiguities towards ~200 sources located within the Solar circle using archival HI data. These distances are used to calculate bolometric luminosities and estimate the survey completeness (~2x10^4 lsun). In total, we calculate the distance and luminosity of ~1650 sources, one third of which are above the survey's completeness threshold. Examination of the sample's longitude, latitude, radial velocities and mid-infrared images has identified ~120 small groups of sources, many of which are associated with well known star formation complexes, such as W43, W49 and W51. We compare the positional distribution of the sample with the expected locations of the spiral arms, assuming a model of the Galaxy consisting of fou...

  5. Quality control of the RMS US flood model

    Science.gov (United States)

    Jankowfsky, Sonja; Hilberts, Arno; Mortgat, Chris; Li, Shuangcai; Rafique, Farhat; Rajesh, Edida; Xu, Na; Mei, Yi; Tillmanns, Stephan; Yang, Yang; Tian, Ye; Mathur, Prince; Kulkarni, Anand; Kumaresh, Bharadwaj Anna; Chaudhuri, Chiranjib; Saini, Vishal

    2016-04-01

    The RMS US flood model predicts the flood risk in the US with a 30 m resolution for different return periods. The model is designed for the insurance industry to estimate the cost of flood risk for a given location. Different statistical, hydrological and hydraulic models are combined to develop the flood maps for different return periods. A rainfall-runoff and routing model, calibrated with observed discharge data, is run with 10 000 years of stochastic simulated precipitation to create time series of discharge and surface runoff. The 100, 250 and 500 year events are extracted from these time series as forcing for a two-dimensional pluvial and fluvial inundation model. The coupling of all the different models which are run on the large area of the US implies a certain amount of uncertainty. Therefore, special attention is paid to the final quality control of the flood maps. First of all, a thorough quality analysis of the Digital Terrain model and the river network was done, as the final quality of the flood maps depends heavily on the DTM quality. Secondly, the simulated 100 year discharge in the major river network (600 000 km) is compared to the 100 year discharge derived using extreme value distribution of all USGS gauges with more than 20 years of peak values (around 11 000 gauges). Thirdly, for each gauge the modelled flood depth is compared to the depth derived from the USGS rating curves. Fourthly, the modelled flood depth is compared to the base flood elevation given in the FEMA flood maps. Fifthly, the flood extent is compared to the FEMA flood extent. Then, for historic events we compare flood extents and flood depths at given locations. Finally, all the data and spatial layers are uploaded on geoserver to facilitate the manual investigation of outliers. The feedback from the quality control is used to improve the model and estimate its uncertainty.

  6. The Scaling of the RMS with Dwell Time in NANOGrav Pulsars

    CERN Document Server

    Handzo, Emma; Lommen, Andrea N; Perrodin, Delphine

    2015-01-01

    Pulsar Timing Arrays (PTAs) are collections of well-timed millisecond pulsars that are being used as detectors of gravitational waves (GWs). Given current sensitivity, projected improvements in PTAs and the predicted strength of the GW signals, the detection of GWs with PTAs could occur within the next decade. One way we can improve a PTA is to reduce the measurement noise present in the pulsar timing residuals. If the pulsars included in the array display uncorrelated noise, the root mean square (RMS) of the timing residuals is predicted to scale as $\\mathrm{T}^{-1/2}$, where T is the dwell time per observation. In this case, the sensitivity of the array can be increased by increasing T. We studied the 17 pulsars in the five year North American Nanohertz Observatory for Gravitational Waves (NANOGrav) data set to determine if the noise in the timing residuals of the pulsars observed was consistent with this property. For comparison, we performed the same analysis on PSR B1937+21, a pulsar that is known to dis...

  7. Pulsed inductive HF laser

    Energy Technology Data Exchange (ETDEWEB)

    Razhev, A M; Kargapol' tsev, E S [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Churkin, D S; Demchuk, S V [Novosibirsk State University, Novosibirsk (Russian Federation)

    2016-03-31

    We report the results of experimentally investigated dependences of temporal, spectral and spatial characteristics of an inductive HF-laser generation on the pump conditions. Gas mixtures H{sub 2} – F{sub 2}(NF{sub 3} or SF6{sub 6}) and He(Ne) – H{sub 2} – F{sub 2}(NF{sub 3} or SF{sub 6}) were used as active media. The FWHM pulse duration reached 0.42 μs. This value corresponded to a pulsed power of 45 kW. For the first time, the emission spectrum of an inductive HF laser was investigated, which consisted of seven groups of bands with centres around the wavelengths of 2732, 2736, 2739, 2835, 2837, 2893 and 2913 nm. The cross section profile of the laser beam was a ring with a diameter of about 20 mm and width of about 5 mm. Parameters of laser operation in the repetitively pulsed regime were sufficiently stable. The amplitude instability of light pulses was no greater than 5% – 6%. (lasers)

  8. The CU ground MAX-DOAS instrument: characterization of RMS noise limitations and first measurements near Pensacola, FL of BrO, IO, and CHOCHO

    Directory of Open Access Journals (Sweden)

    S. Coburn

    2011-11-01

    Full Text Available We designed and assembled the University of Colorado Ground Multi AXis Differential Optical Absorption Spectroscopy (CU GMAX-DOAS instrument to retrieve bromine oxide (BrO, iodine oxide (IO, formaldehyde (HCHO, glyoxal (CHOCHO, nitrogen dioxide (NO2 and the oxygen dimer (O4 in the coastal atmosphere of the Gulf of Mexico. The detection sensitivity of DOAS measurements is proportional to the root mean square (RMS of the residual spectrum that remains after all absorbers have been subtracted. Here we describe the CU GMAX-DOAS instrument and demonstrate that the hardware is capable of attaining RMS of ∼6 × 10−6 from solar stray light noise tests using high photon count spectra (compatible within a factor of two with photon shot noise.

    Laboratory tests revealed two critical instrument properties that, in practice, can limit the RMS: (1 detector non-linearity noise, RMSNLin, and (2 temperature fluctuations that cause variations in optical resolution (full width at half the maximum, FWHM, of atomic emission lines and give rise to optical resolution noise, RMSFWHM. The non-linearity of our detector is low (∼10−2 yet – unless actively controlled – is sufficiently large to create RMSNLin of up to 2 × 10−4. The optical resolution is sensitive to temperature changes (0.03 detector pixels °C−1 at 334 nm, and temperature variations of 0.1°C can cause RMSFWHM of ~1 × 10−4. Both factors were actively addressed in the design of the CU GMAX-DOAS instrument. With an integration time of 60 s the instrument can reach RMS noise of 3 × 10−5, and typical RMS in field measurements ranged from 6 × 10−5 to 1.4 × 10−4.

    The CU GMAX-DOAS was set up at a coastal site near Pensacola, Florida, where we detected BrO, IO and CHOCHO in the marine boundary layer (MBL, with daytime

  9. Improving Critical Thinking Skills of College Students through RMS Model for Learning Basic Concepts in Science

    Science.gov (United States)

    Muhlisin, Ahmad; Susilo, Herawati; Amin, Mohamad; Rohman, Fatchur

    2016-01-01

    The purposes of this study were to: 1) Examine the effect of RMS learning model towards critical thinking skills. 2) Examine the effect of different academic abilities against critical thinking skills. 3) Examine the effect of the interaction between RMS learning model and different academic abilities against critical thinking skills. The research…

  10. Improving Critical Thinking Skills of College Students through RMS Model for Learning Basic Concepts in Science

    Science.gov (United States)

    Muhlisin, Ahmad; Susilo, Herawati; Amin, Mohamad; Rohman, Fatchur

    2016-01-01

    The purposes of this study were to: 1) Examine the effect of RMS learning model towards critical thinking skills. 2) Examine the effect of different academic abilities against critical thinking skills. 3) Examine the effect of the interaction between RMS learning model and different academic abilities against critical thinking skills. The research…

  11. The ubiquity of the rms-flux relation in black hole X-ray binaries

    NARCIS (Netherlands)

    Heil, L.M.; Vaughan, S.; Uttley, P.

    2012-01-01

    We have investigated the short-term linear relation between the rms variability and the flux in 1961 observations of nine black hole X-ray binaries. The rms-flux relation for the 1-10 Hz range is ubiquitously observed in any observation with good variability signal-to-noise ratio (>3 per cent, 1-10 

  12. HF Interference, Procedures and Tools (Interferences HF, procedures et outils)

    Science.gov (United States)

    2007-06-01

    such sources. The existing HF background noise possibly may be increased via ground wave and/or sky wave propagation. Increase of the existing HF...télécommunications filaires à large bande. Les télécommunications via le réseau électrique courant, dites PowerLine Communications (PLT ou PLC) et diverses...cumulative de nombreuses sources de même type. Le bruit de fond HF existant risque d’être augmenté par propagation de l’onde terrestre et/ou aérienne

  13. JSATS Detector Field Manual

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eric Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flory, Adam E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamarche, Brian L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-06-01

    The Juvenile Salmon Acoustic Telemetry System (JSATS) Detector is a software and hardware system that captures JSATS Acoustic Micro Transmitter (AMT) signals. The system uses hydrophones to capture acoustic signals in the water. This analog signal is then amplified and processed by the Analog to Digital Converter (ADC) and Digital Signal Processor (DSP) board in the computer. This board digitizes and processes the acoustic signal to determine if a possible JSATS tag is present. With this detection, the data will be saved to the computer for further analysis. This document details the features and functionality of the JSATS Detector software. The document covers how to install the software, setup and run the detector software. The document will also go over the raw binary waveform file format and CSV files containing RMS values

  14. JSATS Detector Field Manual

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eric Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flory, Adam E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamarche, Brian L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-06-01

    The Juvenile Salmon Acoustic Telemetry System (JSATS) Detector is a software and hardware system that captures JSATS Acoustic Micro Transmitter (AMT) signals. The system uses hydrophones to capture acoustic signals in the water. This analog signal is then amplified and processed by the Analog to Digital Converter (ADC) and Digital Signal Processor (DSP) board in the computer. This board digitizes and processes the acoustic signal to determine if a possible JSATS tag is present. With this detection, the data will be saved to the computer for further analysis. This document details the features and functionality of the JSATS Detector software. The document covers how to install the software, setup and run the detector software. The document will also go over the raw binary waveform file format and CSV files containing RMS values

  15. Marburg Hemorrhagic Fever (Marburg HF)

    Science.gov (United States)

    ... CDC Cancel Submit Search The CDC Marburg hemorrhagic fever (Marburg HF) Note: Javascript is disabled or is ... first recognized in 1967, when outbreaks of hemorrhagic fever occurred simultaneously in laboratories in Marburg and Frankfurt, ...

  16. Remote Manipulator System (RMS)-based Controls-Structures Interaction (CSI) flight experiment feasibility study

    Science.gov (United States)

    Demeo, Martha E.

    1990-01-01

    The feasibility of an experiment which will provide an on-orbit validation of Controls-Structures Interaction (CSI) technology, was investigated. The experiment will demonstrate the on-orbit characterization and flexible-body control of large flexible structure dynamics using the shuttle Remote Manipulator System (RMS) with an attached payload as a test article. By utilizing existing hardware as well as establishing integration, operation and safety algorithms, techniques and procedures, the experiment will minimize the costs and risks of implementing a flight experiment. The experiment will also offer spin-off enhancement to both the Shuttle RMS (SRMS) and the Space Station RMS (SSRMS).

  17. Hf Transition Probabilities and Abundances

    CERN Document Server

    Lawler, J E; Labby, Z E; Sneden, C; Cowan, J J; Ivans, I I

    2006-01-01

    Radiative lifetimes from laser-induced fluorescence measurements, accurate to about +/- 5 percent, are reported for 41 odd-parity levels of Hf II. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf II. Approximately half of these new transition probabilities overlap with recent independent measurements using a similar approach. The two sets of measurements are found to be in good agreement for measurements in common. Our new laboratory data are applied to refine the hafnium photospheric solar abundance and to determine hafnium abundances in 10 metal-poor giant stars with enhanced r-process abundances. For the Sun we derive log epsilon (Hf) = 0.88 +/- 0.08 from four lines; the uncertainty is dominated by the weakness of the lines and their blending by other spectral features. Within the uncertainties of our analysis, the r-process-rich stars possess constant Hf/La and Hf/Eu abundance ratios, log epsilon (Hf...

  18. GEO 600 and the GEO-HF upgrade program: successes and challenges

    CERN Document Server

    Dooley, K L; Adams, T; Affeldt, C; Bisht, A; Bogan, C; Degallaix, J; Gräf, C; Hild, S; Hough, J; Khalaidovski, A; Lastzka, N; Lough, J; Lück, H; Macleod, D; Nuttall, L; Prijatelj, M; Schnabel, R; Schreiber, E; Slutsky, J; Sorazu, B; Strain, K A; Vahlbruch, H; Was, M; Willke, B; Wittel, H; Danzmann, K; Grote, H

    2015-01-01

    The German-British laser-interferometric gravitational wave detector GEO 600 is in its 14th year of operation since its first lock in 2001. After GEO 600 participated in science runs with other first-generation detectors, a program known as GEO-HF began in 2009. The goal was to improve the detector sensitivity at high frequencies with technologically advanced yet minimally invasive upgrades. Simultaneously, the detector would record science quality data in between commissioning activities. As of early 2014, all of the planned upgrades have been carried out and sensitivity improvements of up to a factor of four at the high-frequency end of the observation band have been achieved. Besides science data collection, an experimental program is ongoing with the goal to further improve the sensitivity and evaluate future detector technologies. We summarize the results of the GEO-HF program to date and discuss its successes and challenges.

  19. STS 41-D mission specialist Judith Resnik trains on the RMS

    Science.gov (United States)

    1983-01-01

    STS 41-D mission specialist Judith Resnik prepares for training on the remote manipulator system (RSM) on board the shuttle mission simulator (SMS). She is on the SMS aft deck facing the RMS translation hand control and overhead starboard window.

  20. An efficient method for calculating RMS von Mises stress in a random vibration environment

    Energy Technology Data Exchange (ETDEWEB)

    Segalman, D.J.; Fulcher, C.W.G.; Reese, G.M.; Field, R.V. Jr. [Sandia National Labs., Albuquerque, NM (United States). Structural Dynamics and Vibration Control Dept.

    1998-02-01

    An efficient method is presented for calculation of RMS von Mises stresses from stress component transfer functions and the Fourier representation of random input forces. An efficient implementation of the method calculates the RMS stresses directly from the linear stress and displacement modes. The key relation presented is one suggested in past literature, but does not appear to have been previously exploited in this manner.

  1. An efficient method for calculating RMS von Mises stress in a random vibration environment

    Energy Technology Data Exchange (ETDEWEB)

    Segalman, D.J.; Fulcher, C.W.G.; Reese, G.M.; Field, R.V. Jr. [Sandia National Labs., Albuquerque, NM (United States). Structural Dynamics and Vibration Control Dept.

    1997-12-01

    An efficient method is presented for calculation of RMS von Mises stresses from stress component transfer functions and the Fourier representation of random input forces. An efficient implementation of the method calculates the RMS stresses directly from the linear stress and displacement modes. The key relation presented is one suggested in past literature, but does not appear to have been previously exploited in this manner.

  2. Development and characterization of the CU ground MAX-DOAS instrument: lowering RMS noise and first measurements of BrO, IO, and CHOCHO near Pensacola, FL

    Directory of Open Access Journals (Sweden)

    S. Coburn

    2011-01-01

    Full Text Available We designed and assembled the University of Colorado Ground Multi AXis Differential Optical Absorption Spectroscopy (CU GMAX-DOAS instrument to retrieve bromine oxide (BrO, iodine oxide (IO, formaldehyde (HCHO, glyoxal (CHOCHO, nitrogen dioxide (NO2 and the oxygen dimer O4 in the coastal atmosphere of the Gulf of Mexico. The detection sensitivity of DOAS measurements is directly proportional to the root mean square (RMS of the residual spectrum that remains after all absorbers have been subtracted. Here we describe the CU GMAX-DOAS instrument and demonstrate that the hardware is capable of attaining RMS values of ~6 × 10-6 without apparent limitations other than photon shot noise.

    Laboratory tests revealed two factors that, in practice, limit the RMS: (1 detector non-linearity noise, RMSNLin, and (2 temperature fluctuations that cause variations in optical resolution (full width at half the maximum, FWHM, of atomic emission lines and give rise to optical resolution noise, RMSFWHM. The non-linearity of our detector is low (~10−3 yet – unless actively controlled – is sufficiently large to create a RMSNLin limit of up to 1.4 × 10-4. The optical resolution is sensitive to temperature changes (0.03 detector pixels/°C at 334 nm, and temperature variations of 0.1 °C can cause residual RMSFWHM of ~1 × 10-4. Both factors were actively addressed in the design of the CU GMAX-DOAS instrument.

    The CU GMAX-DOAS was set up at a coastal site near Pensacola, FL, where we detected BrO, IO and CHOCHO in the marine boundary layer (MBL, with daytime average tropospheric vertical column densities, VCDs, of ~2 × 1013 molec cm−2, 8 × 1012 molec cm−2 and 4 × 1014 molec cm−2, respectively. HCHO and NO2 were also detected with typical MBL VCDs of 1

  3. Real-time RMS active damping augmentation: Heavy and very light payload evaluations

    Science.gov (United States)

    Demeo, Martha E.; Gilbert, Michael G.; Lepanto, Janet A.; Flueckiger, Karl W.; Bains, Elizabeth M.; Jensen, Mary C.

    1994-01-01

    Controls-Structures Integration Technology has been applied to the Space Shuttle Remote Manipulator System (RMS) to improve on-orbit performance. The objective was to actively damp undesired oscillatory motions of the RMS following routine payload maneuvering and Shuttle attitude control thruster firings. Simulation of active damping was conducted in the real-time, man-in-the-loop Systems Engineering Simulator at NASA's Johnson Space Center. The simulator was used to obtain qualitative and quantitative data on active damping performance from astronaut operators. Using a simulated three-axis accelerometer mounted on the RMS, 'sensed' vibration motions were used to generate joint motor commands that reduced the unwanted oscillations. Active damping of the RMS with heavy and light attached payloads was demonstrated in this study. Five astronaut operators examined the performance of active damping following operator commanded RMS maneuvers and Shuttle thruster firings. Noticeable improvements in the damping response of the RMS with the heavy, Hubble Space Telescope payload and the very light, astronaut in Manipulator Foot Restraint payload were observed. The potential of active damping to aid in precisely maneuvering payloads was deemed significant.

  4. R.M.S Titanic 2003 Expedition on the Russian Research Vessel Akademik Mstislav Keldysh between 20030622 and 20030702

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — As the leading ocean agency, and as per the Guidelines for Research, Exploration and Salvage of RMS Titanic, issued under the authority of the RMS Titanic Maritime...

  5. Analytical evaluation of DC capacitor RMS current and voltage ripple in neutral-point clamped inverters

    Indian Academy of Sciences (India)

    K S GOPALAKRISHNAN; SANTOSH JANAKIRAMAN; SOUMITRA DAS; G NARAYANAN

    2017-06-01

    The sizing of the DC-link capacitor in a three-level inverter is based on the RMS current flowing through it. This paper analyses the DC-link capacitor RMS current in a neutral-point clamped (NPC) inverter and expresses the same as a function of modulation index, line-side current amplitude and power factor. Analytical closed-form expressions are derived for the capacitor RMS current for single-phase half-bridge,single-phase full-bridge and three-phase three-leg topologies of a three-level inverter. The worst-case capacitor current stress is determined for each topology based on the analytical expressions. Further, analytical expressions are derived for the RMS values of low-frequency and high-frequency capacitor currents. These expressions are then used to estimate voltage ripple across the DC capacitor for sinusoidally modulated three-phase NPC inverter. The analytical expressions for the RMS current and voltage ripple are validated experimentally over a wide range of operating points.

  6. Development and characterization of the CU ground MAX-DOAS instrument: lowering RMS noise and first measurements of BrO, IO, and CHOCHO near Pensacola, FL

    Science.gov (United States)

    Coburn, S.; Dix, B.; Sinreich, R.; Volkamer, R.

    2011-01-01

    We designed and assembled the University of Colorado Ground Multi AXis Differential Optical Absorption Spectroscopy (CU GMAX-DOAS) instrument to retrieve bromine oxide (BrO), iodine oxide (IO), formaldehyde (HCHO), glyoxal (CHOCHO), nitrogen dioxide (NO2) and the oxygen dimer O4 in the coastal atmosphere of the Gulf of Mexico. The detection sensitivity of DOAS measurements is directly proportional to the root mean square (RMS) of the residual spectrum that remains after all absorbers have been subtracted. Here we describe the CU GMAX-DOAS instrument and demonstrate that the hardware is capable of attaining RMS values of ~6 × 10-6 without apparent limitations other than photon shot noise. Laboratory tests revealed two factors that, in practice, limit the RMS: (1) detector non-linearity noise, RMSNLin, and (2) temperature fluctuations that cause variations in optical resolution (full width at half the maximum, FWHM, of atomic emission lines) and give rise to optical resolution noise, RMSFWHM. The non-linearity of our detector is low (~10-3) yet - unless actively controlled - is sufficiently large to create a RMSNLin limit of up to 1.4 × 10-4. The optical resolution is sensitive to temperature changes (0.03 detector pixels/°C at 334 nm), and temperature variations of 0.1 °C can cause residual RMSFWHM of ~1 × 10-4. Both factors were actively addressed in the design of the CU GMAX-DOAS instrument. The CU GMAX-DOAS was set up at a coastal site near Pensacola, FL, where we detected BrO, IO and CHOCHO in the marine boundary layer (MBL), with daytime average tropospheric vertical column densities, VCDs, of ~2 × 1013 molec cm-2, 8 × 1012 molec cm-2 and 4 × 1014 molec cm-2, respectively. HCHO and NO2 were also detected with typical MBL VCDs of 1 × 1016 and 3 × 1015. These are the first measurements of BrO, IO and CHOCHO over the Gulf of Mexico. The atmospheric implications of these observations for elevated mercury wet deposition rates in this area are briefly

  7. Phase Angle Calculation Dynamics of Type 4 Wind Turbines in RMS Simulations during Severe Voltage Dips

    DEFF Research Database (Denmark)

    Altin, Müfit; Göksu, Ömer; Sørensen, Poul Ejnar;

    2016-01-01

    the simulation convergence without adding complexity to the generic models, a first order filtering approach is proposed as a phase angle calculation algorithm in the grid synchronization of the rms type 4 wind turbine models. The proposed approach provides robustness for the simulation of large scale power......In order to conduct power system simulations with high shares of wind energy, standard wind turbine models, which are aimed to be generic rms models for a wide range of wind turbine types, have been developed. As a common practice of rms simulations, the power electronic interface of wind turbines...... is assumed to be ideally synchronized, i.e. grid synchronization (e.g. PLL) is not included in simplified wind turbine models. As will be shown in this paper, this practice causes simulation convergence problems during severe voltage dips and when the loss of synchronism occurs. In order to provide...

  8. The delivery of the last HF wedge at VNIITF, Snezhinsk, Russia

    CERN Multimedia

    Tiziano Camporesi

    2003-01-01

    A little ceremony celebrated the delivery of the last of the 36 HF detector modules in Snezhinsk. During the ceremony the managers and coordinators of the VNIITF workshops were given little mementos to mark their collaboration with CERN-CMS. It is worth noticing that the last module was delivered two months ahead of schedule.

  9. Astronauts Gardner and Allen on the RMS after recapture of Westar VI

    Science.gov (United States)

    1984-01-01

    Astronaut Dale A. Gardner, left, holds a 'For Sale' sign, making light reference to the status of the recaptured communications satellite. Astronaut Joseph P. ALlen IV stands on the mobile foot restraint (MFR), which in tandem with the remote manipulator system (RMS) arm served as a cherry-picker for capture efforts.

  10. The rms-flux relation of Cyg X-2 in the horizontal branch

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We have investigated the relation between the root mean square(rms) variability and the X-ray flux(rms-flux relation) of the Z source Cyg X-2,and as well the energy dependence based on the Rossi X-ray Timing Explorer(RXTE) observations.We currently focus on the horizontal branch(HB),due to the negative correlation in flux of the soft and the hard X-rays.The rms-flux correlation has energy dependence as follows:positive at hard X-rays(above 10 keV) but negative at soft X-rays(below 10 keV).This provides a feature different from the previous one,and may be suggestive of different origins of X-rays below and above 10 keV.Nevertheless,the overall spectrum can be well fitted with a model consisting of a blackbody and Comptonization components,but the fitting results do not reveal any features around 10 keV that could account for such a change in the rms-flux relation.

  11. Accuracy of the surface electromyography RMS processing for the diagnosis of myogenous temporomandibular disorder.

    Science.gov (United States)

    Berni, Kelly Cristina dos Santos; Dibai-Filho, Almir Vieira; Pires, Paulo Fernandes; Rodrigues-Bigaton, Delaine

    2015-08-01

    Due to the multifactor etiology of temporomandibular disorder (TMD), the precise diagnosis remains a matter of debate and validated diagnostic tools are needed. The aim was to determine the accuracy of surface electromyography (sEMG) activity, assessed in the amplitude domain by the root mean square (RMS), in the diagnosis of TMD. One hundred twenty-three volunteers were evaluated using the Research Diagnostic Criteria for Temporomandibular Disorders and distributed into two groups: women with myogenous TMD (n=80) and women without TMD (n=43). The volunteers were then submitted to sEMG evaluation of the anterior temporalis, masseter and suprahyoid muscles at rest and during maximum voluntary teeth clenching (MVC) on parafilm. The accuracy, sensitivity and specificity of the muscle activity were analyzed. Differences between groups were found in all muscles analyzed at rest as well as in the masseter and suprahyoid muscles during MVC on parafilm. Moderate accuracy (AUC: 0.74-0.84) of the RMS sEMG was found in all muscles regarding the diagnosis of TMD at rest and in the suprahyoid muscles during MVC on parafilm. Moreover, sensitivity ranging from 71.3% to 80% and specificity from 60.5% to 76.6%. In contrast, RMS sEMG did not exhibit acceptable degrees of accuracy in the other masticatory muscles during MVC on parafilm. It was concluded that the RMS sEMG is a complementary tool for clinical diagnosis of the myogenous TMD.

  12. The CU ground MAX-DOAS instrument: characterization of RMS noise limitations and first measurements near Pensacola, FL of BrO, IO, and CHOCHO

    Science.gov (United States)

    Coburn, S.; Dix, B.; Sinreich, R.; Volkamer, R.

    2011-11-01

    We designed and assembled the University of Colorado Ground Multi AXis Differential Optical Absorption Spectroscopy (CU GMAX-DOAS) instrument to retrieve bromine oxide (BrO), iodine oxide (IO), formaldehyde (HCHO), glyoxal (CHOCHO), nitrogen dioxide (NO2) and the oxygen dimer (O4) in the coastal atmosphere of the Gulf of Mexico. The detection sensitivity of DOAS measurements is proportional to the root mean square (RMS) of the residual spectrum that remains after all absorbers have been subtracted. Here we describe the CU GMAX-DOAS instrument and demonstrate that the hardware is capable of attaining RMS of ∼6 × 10-6 from solar stray light noise tests using high photon count spectra (compatible within a factor of two with photon shot noise). Laboratory tests revealed two critical instrument properties that, in practice, can limit the RMS: (1) detector non-linearity noise, RMSNLin, and (2) temperature fluctuations that cause variations in optical resolution (full width at half the maximum, FWHM, of atomic emission lines) and give rise to optical resolution noise, RMSFWHM. The non-linearity of our detector is low (∼10-2) yet - unless actively controlled - is sufficiently large to create RMSNLin of up to 2 × 10-4. The optical resolution is sensitive to temperature changes (0.03 detector pixels °C-1 at 334 nm), and temperature variations of 0.1°C can cause RMSFWHM of ~1 × 10-4. Both factors were actively addressed in the design of the CU GMAX-DOAS instrument. With an integration time of 60 s the instrument can reach RMS noise of 3 × 10-5, and typical RMS in field measurements ranged from 6 × 10-5 to 1.4 × 10-4. The CU GMAX-DOAS was set up at a coastal site near Pensacola, Florida, where we detected BrO, IO and CHOCHO in the marine boundary layer (MBL), with daytime average tropospheric vertical column densities (average of data above the detection limit), VCDs, of ∼2 × 1013 molec cm-2, 8 × 1012 molec cm-2 and 4 × 1014 molec cm-2, respectively. HCHO and

  13. Environmentally friendly HF (DF) lasers

    Science.gov (United States)

    Apollonov, V. V.

    2016-08-01

    Dedicated to the 100th anniversary of the birth of Academician A M Prokhorov, this paper reviews the physics of self-sustained volume discharge without preionization—self-initiated volume discharge (SIVD)—in the working mixtures of non-chain hydrofluoride HF (deuterofluoride (DF)) lasers. The dynamics of SIVD in discharge gaps with different geometries is thoroughly described. The mechanisms for the restriction of current density in a diffuse channel in electric discharges in SF6 and SF6 based mixtures (which determines whether SIVD is possible) are proposed and analyzed using simple models. The most probable mechanisms are the electron impact dissociation of SF6 and other mixture components, electron-ion recombination and electron attachment to vibrationally excited SF6 molecules. Starting from a comparative analysis of the rate coefficients of these processes, it is shown that electron-ion recombination is capable of compensating for electron detachment from negative ions via electron impact. It is also established that SIVD is not only observed in SF6, but also in other strongly electronegative gases. The factors that determine the uniformity of the active medium in non-chain HF (DF) lasers are analyzed. Some special features of non-chain HF (DF) lasers with different apertures operating are carefully examined. Consideration is given to the problem of increasing the aperture and discharge volume of non-chain HF (DF) lasers. Based on our experimental results, the possibility of increasing the energy of such lasers to ~1 kJ and above is shown.

  14. Numerical modeling of radioactive neutron capture influence of Hf isotopic composition dynamics rate in the RBMK-1500 reactor

    CERN Document Server

    Jurkevicius, A; Auzelyte, V; Remeikis, V

    2000-01-01

    The nuclide composition of the nuclear fuel and isotopic composition of the hafnium in the radial neutron flux detectors of the RBMK-1500 reactor were numerically modelled. The sequence SAS2 from package SCALE 4.3 was used for calculations. The nuclear fuel nuclide concentrations, the concentration of Hf isotopes, the neutron absorption rate on Hf isotopes and summary absorption rate dependences on the fuel assembly burn up are presented. (author)

  15. Vibrational relaxation of hydrogen fluoride by HF dimers in a laser excited nozzle beam

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, E.L.; Rubahn, H.; Toennies, J.P.; Wanner, J.

    1986-09-01

    An HF nozzle beam and a cw HF laser beam in a coaxial and antiparallel arrangement facilitated exciting HF molecules vibrationally in v-italic = 1,J-italic up to the saturation limit. A beam consisting exclusively of monomeric HF was generated by heating the beam source to 600 K and was confirmed using a mass spectrometer. Energy-flux measurements made using a bolometer indicate that the vibrational energy distribution initiated by the laser is conserved, confirming that V--T energy transfer to monomers is slow. The maximum measured flux of HF(v-italic = 1,J-italic) molecules was 1.5 x 10/sup 17/ molecules s/sup -1/ sr/sup -1/ at 670 mbar stagnation pressure. Beams consisting of a mixture of monomeric and polymeric HF were generated using appropriate combinations of source temperature and pressure. In the presence of dimers, the excited monomers relax rapidly by a fast V--V transfer and subsequent predissociation of the metastable dimers. The loss of beam energy due to energy transport by the departing dimer fragments was detected bolometrically. The laser-induced depletion of dimers was determined over a wide source pressure range at T-italic/sub 0/ = 300 K using a mass spectrometer. From a kinetic model of these dimer-depletion data, the product of cross section and transfer probability for V--V energy transfer from HF (v-italic = 1) monomers to dimers was deduced to be 14 A-circle/sup 2/. The terminal-dimer-concentration equation for HF nozzle beams was refined. An analysis of the energy fluxes measured by the bolometer with no laser excitation of the beam revealed that, for an HF nozzle beam, the flow from the source to the detector is, in general, nonisenthalpic due to the onset of dimerization. Mach-number focusing enriches the dimer mole fractions detected by the bolometer.

  16. The application of root mean square electrocardiography (RMS ECG for the detection of acquired and congenital long QT syndrome.

    Directory of Open Access Journals (Sweden)

    Robert L Lux

    Full Text Available BACKGROUND: Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK closely reflects the mean ventricular action potential duration while the RMS T wave width (TW tracks the dispersion of repolarization timing. Here, we tested the precision of RMS ECG to assess ventricular repolarization in humans in the setting of drug-induced and congenital Long QT Syndrome (LQTS. METHODS: RMS ECG signals were derived from high-resolution 24 hour Holter monitor recordings from 68 subjects after receiving placebo and moxifloxacin and from standard 12 lead ECGs obtained in 97 subjects with LQTS and 97 age- and sex-matched controls. RTPK, QTRMS and RMS TW intervals were automatically measured using custom software and compared to traditional QT measures using lead II. RESULTS: All measures of repolarization were prolonged during moxifloxacin administration and in LQTS subjects, but the variance of RMS intervals was significantly smaller than traditional lead II measurements. TW was prolonged during moxifloxacin and in subjects with LQT-2, but not LQT-1 or LQT-3. CONCLUSION: These data validate the application of RMS ECG for the detection of drug-induced and congenital LQTS. RMS ECG measurements are more precise than the current standard of care lead II measurements.

  17. The application of root mean square electrocardiography (RMS ECG) for the detection of acquired and congenital long QT syndrome.

    Science.gov (United States)

    Lux, Robert L; Sower, Christopher Todd; Allen, Nancy; Etheridge, Susan P; Tristani-Firouzi, Martin; Saarel, Elizabeth V

    2014-01-01

    Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG) provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK) closely reflects the mean ventricular action potential duration while the RMS T wave width (TW) tracks the dispersion of repolarization timing. Here, we tested the precision of RMS ECG to assess ventricular repolarization in humans in the setting of drug-induced and congenital Long QT Syndrome (LQTS). RMS ECG signals were derived from high-resolution 24 hour Holter monitor recordings from 68 subjects after receiving placebo and moxifloxacin and from standard 12 lead ECGs obtained in 97 subjects with LQTS and 97 age- and sex-matched controls. RTPK, QTRMS and RMS TW intervals were automatically measured using custom software and compared to traditional QT measures using lead II. All measures of repolarization were prolonged during moxifloxacin administration and in LQTS subjects, but the variance of RMS intervals was significantly smaller than traditional lead II measurements. TW was prolonged during moxifloxacin and in subjects with LQT-2, but not LQT-1 or LQT-3. These data validate the application of RMS ECG for the detection of drug-induced and congenital LQTS. RMS ECG measurements are more precise than the current standard of care lead II measurements.

  18. MRI visualization of endogenous neural progenitor cell migration along the RMS in the adult mouse brain

    DEFF Research Database (Denmark)

    Vreys, Ruth; Vande Velde, Greetje; Krylychkina, Olga

    2010-01-01

    The adult rodent brain contains neural progenitor cells (NPCs), generated in the subventricular zone (SVZ), which migrate along the rostral migratory stream (RMS) towards the olfactory bulb (OB) where they differentiate into neurons. The aim of this study was to visualize endogenous NPC migration...... along the RMS with magnetic resonance imaging (MRI) in adult healthy mice. We evaluated various in situ (in vivo) labeling approaches using micron-sized iron oxide particles (MPIOs) on their efficiency to label endogenous NPCs. In situ labeling and visualization of migrating NPCs were analyzed...... by a longitudinal MRI study and validated with histology. Here, we visualized endogenous NPC migration in the mouse brain by in vivo MRI and demonstrated accumulation of MPIO-labeled NPCs in the OB over time with ex vivo MRI. Furthermore, we investigated the influence of in situ injection of MPIOs on adult...

  19. Aufwand und Nutzen des Electronic Resource Management Systems RMS an der UB Kassel

    Directory of Open Access Journals (Sweden)

    Tobias Pohlmann

    2016-03-01

    The university library of Kassel therefore uses SemperTool’s web-based electronic resource management system RMS. This paper presents the functionality of this system and makes an estimate of the expenditure of work necessary to enter all relevant information about licensed databases, e-book and e-journal packages with the corresponding individual resources. It also describes existing and projected tools for analysis and evaluation, which are decisive for the usefulness of such a system, and concludes with the satisfaction reached at the university library of Kassel. These experiences may help other libraries to decide whether or not to introduce RMS or a comparable system.

  20. The pseudonoise test set: Communication system's performance evaluation based upon RMS error testing

    Science.gov (United States)

    Wallace, G. R.; Gussow, S. S.; Salter, W. E.; Weathers, G. D.

    1972-01-01

    A pseudonoise (PN) test set was built to provide a relatively easy means of accurately determining the end-to-end rms error introduced by a communication system when subjected to wideband data. It utilizes a filtered pseudorandom sequence generator as a wideband data source, providing a convenient means for digitally delaying the input reference signal for comparison with the distorted test communication system output. In addition to providing a means to measure the end-to-end rms error and the average delay of a communication system, the PN test set also provides a means to determine the tested system's impulse response and correlation function. The theory of PN testing is discussed in detail along with the most difficult aspects of implementation, the building of matched filter pairs. Both analytical and empirical results are reported which support the contentions that this is an accurate and practical way to acquire figures of merit for complete communication systems.

  1. Review: Rusticle Formation on the RMS Titanic and the Potential Influence ofOceanography

    Science.gov (United States)

    2017-01-12

    Brenda Little 1 23 Your article is protected by copyright and all rights are held exclusively by Springer Science+Business Media New York (outside...Oceanography Maxsimo Salazar1 • Brenda Little1 Published online: 12 January 2017 Springer Science+Business Media New York (outside the USA) 2017...Abstract Meter length iron- rich rusticles on the RMS Titanic contain bacteria that reportedly mobilize iron from the ship structure at a rate that will

  2. A thirty second isomer in Hf-171

    NARCIS (Netherlands)

    Campbell, P; Billowes, J; Cochrane, ECA; Cooke, JL; Cooper, TG; Dendooven, P; Evans, DE; Grant, IS; Griffith, JAR; Honkanen, A; Huhta, M; Oinonen, M; Pearson, MR; Penttila, H; Persson, B.L.; Richardson, DS; Tungate, G; Wheeler, PD; Zybert, L; Aysto, J

    1997-01-01

    An isomer has been detected in Hf-171 with a half-life of T-1/2 = 29.5(9) s. The state was populated in the Yb-170(alpha,3n)Hf-171m reaction at a beam energy of E-alpha = 50 MeV in an on-line ion guide isotope separator. The isomeric Hf-17lm(+) beam was extracted from the ion guide, mass-analysed an

  3. A historical study to understand students’ current difficulties about RMS values

    Science.gov (United States)

    Khantine-Langlois, Françoise; Munier, Valérie

    2016-07-01

    Several studies show that students experience more and more difficulties managing the measurements of electrical values in alternating current and that they have trouble making links between theory and practice. They find it difficult to give meaning to root mean square (RMS; or effective) values, which are not understood as average values and are confused with instantaneous values. This shows that students do not clearly differentiate variable and direct currents. In this paper we try, with a historical study and a study of teaching the concept of RMS values, to understand students’ difficulties with this concept. In the first part we present an epistemological analysis of the concept of RMS values, showing that it is multifaceted and can be approached from different points of view. In the second part we analyse the evolution of French secondary school curricula and textbooks from the explicit introduction of variable currents to today, questioning the links between the evolution of the curricula and the evolution of the place of science and technology in our societies. We point out that the evolution of the curricula is linked to the social context and to the connections between science, technology and society, and also to the relationship with mathematics curricula. We show that alternating current is introduced earlier in the curriculum but has gradually lost all phenomenological description. This study allows us to better understand students’ difficulties and to discuss some implications for teaching.

  4. On the rms anisotropy at 7 deg and 10 deg observed in the COBE-DMR two year sky maps

    Science.gov (United States)

    Banday, A. J.; Gorski, K. M.; Tenorio, L.; Wright, E. L.; Smoot, G. F.; Lineweaver, C. H.; Kogut, A.; Hinshaw, G.; Bennett, C. L.

    1994-01-01

    The frequency-independent rms temperature fluctuations determined from the Cosmic Background Explorer-Differential Microwave Radiometer (COBE-DMR) two-year sky maps are used to infer the parameter Q(sub rms-PS), which characterizes the normalization of power-law models of primordial cosmological temperature anisotropy, for a forced fit to a scale-invariant Harrison-Zel'dovich (n = 1) spectral model. Using a joint analysis of the 7 deg and 10 deg 'cross'-rms derived from both the 53 and 90 GHz sky maps, we find Q(sub rms-PS) = 17.0(sub -2.1 sup +2.5) micro Kelvin when the low quadrupole is included, and Q(sub rms-PS) = 19.4(sub -2.1 sup +2.3) micro Kelvin excluding the quadrupole. These results are consistent with the n = 1 fits from more sensitive methods. The effect of the low quadrupole derived from the COBE-DMR data on the inferred Q(sub rms-PS) normalization is investigated. A bias to lower Q(sub rms-PS) is found when the quadrupole is included. The higher normalization for a forced n = 1 fit is then favored by the cross-rms technique.

  5. Absolute Calibration of Si iRMs used for Measurements of Si Paleo-nutrient proxies

    Science.gov (United States)

    Vocke, R. D., Jr.; Rabb, S. A.

    2016-12-01

    Silicon isotope variations (reported as δ30Si and δ29Si, relative to NBS28) in silicic acid dissolved in ocean waters, in biogenic silica and in diatoms are extremely informative paleo-nutrient proxies. The resolution and comparability of such measurements depend on the quality of the isotopic Reference Materials (iRMs) defining the delta scale. We report new absolute Si isotopic measurements on the iRMs NBS28 (RM 8546 - Silica Sand), Diatomite, and Big Batch using the Avogadro measurement approach and comparing them with prior assessments of these iRMs. The Avogadro Si measurement technique was developed by the German Physikalish-Technische Bundesanstalt (PTB) to provide a precise and highly accurate method to measure absolute isotopic ratios in highly enriched 28Si (99.996%) material. These measurements are part of an international effort to redefine the kg and mole based on the Planck constant h and the Avogadro constant NA, respectively (Vocke et al., 2014 Metrologia 51, 361, Azuma et al., 2015 Metrologia 52 360). This approach produces absolute Si isotope ratio data with lower levels of uncertainty when compared to the traditional "Atomic Weights" method of absolute isotope ratio measurement calibration. This is illustrated in Fig. 1 where absolute Si isotopic measurements on SRM 990, separated by 40+ years of advances in instrumentation, are compared. The availability of this new technique does not say that absolute Si isotopic ratios are or ever will be better for normal Si isotopic measurements when seeking isotopic variations in nature, because they are not. However, by determining the absolute isotopic ratios of all the Si iRM scale artifacts, such iRMs become traceable to the metric system (SI); thereby automatically conferring on all the artifact-based δ30Si and δ29Si measurements traceability to the base SI unit, the mole. Such traceability should help reduce the potential of bias between different iRMs and facilitate the replacement of delta

  6. The study of multilayers Fe/Hf and Ni/Hf by slow positron beam technique

    Science.gov (United States)

    Tashiro, Mutsumi; Nakajyo, Terunobu; Murashige, Yusuke; Koizumi, Tomoya; Kanazawa, Ikuzo; Komori, Fumio; Soe, We-Hyo; Yamamoto, Ryoichi; Ito, Yasuo

    1997-05-01

    The S-parameters versus the incident positron energy are measured in the Ni/Hf multilayer, thin Hf film, thin Fe film and the bilayer Fe/Hf. We have analyzed the change in vacancy-type defects in these multilayers and thin films with the deposition temperature in the MBE system.

  7. HfS, Hyperfine Structure Fitting Tool

    CERN Document Server

    Estalella, Robert

    2016-01-01

    HfS is a tool to fit the hyperfine structure of spectral lines, with multiple velocity components. The HfS_nh3 procedures included in HfS fit simultaneously the hyperfine structure of the NH$_3$ (J,K)= (1,1) and (2,2) transitions, and perform a standard analysis to derive $T_\\mathrm{ex}$, NH$_3$ column density, $T_\\mathrm{rot}$, and $T_\\mathrm{k}$. HfS uses a Monte Carlo approach for fitting the line parameters. Especial attention is paid to the derivation of the parameter uncertainties. HfS includes procedures that make use of parallel computing for fitting spectra from a data cube.

  8. Detector Unit

    CERN Multimedia

    1960-01-01

    Original detector unit of the Instituut voor Kernfysisch Onderzoek (IKO) BOL project. This detector unit shows that silicon detectors for nuclear physics particle detection were already developed and in use in the 1960's in Amsterdam. Also the idea of putting 'strips' onto the silicon for high spatial resolution of a particle's impact on the detector were implemented in the BOL project which used 64 of these detector units. The IKO BOL project with its silicon particle detectors was designed, built and operated from 1965 to roughly 1977. Detector Unit of the BOL project: These detectors, notably the ‘checkerboard detector’, were developed during the years 1964-1968 in Amsterdam, The Netherlands, by the Natuurkundig Laboratorium of the N.V. Philips Gloeilampen Fabrieken. This was done in close collaboration with the Instituut voor Kernfysisch Onderzoek (IKO) where the read-out electronics for their use in the BOL Project was developed and produced.

  9. Infrared detectors

    CERN Document Server

    Rogalski, Antonio

    2010-01-01

    This second edition is fully revised and reorganized, with new chapters concerning third generation and quantum dot detectors, THz detectors, cantilever and antenna coupled detectors, and information on radiometry and IR optics materials. Part IV concerning focal plane arrays is significantly expanded. This book, resembling an encyclopedia of IR detectors, is well illustrated and contains many original references … a really comprehensive book.-F. Sizov, Institute of Semiconductor Physics, National Academy of Sciences, Kiev, Ukraine

  10. Production of heavy element and search for new isotopes at JAERI-RMS

    Energy Technology Data Exchange (ETDEWEB)

    Ikuta, Tomohiko [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    The new neutron deficient isotope {sup 209}Th and {sup 212}Pa have been produced in heavy ion induced fusion evaporation reactions. The evaporation residues were separated in-flight by the JAERI recoil mass separator (JAERI-RMS). The {alpha}-decay energy of {sup 209}Th and {sup 212}Pa are 8.080(50) MeV and 8.270(30) MeV, respectively. The corresponding half-lives are 3.8{sub -1.5}{sup +6.9} ms and 5.1{sub -1.9}{sup +6.1} ms. (author)

  11. Liquid-Xe detector for contraband detection

    Energy Technology Data Exchange (ETDEWEB)

    Vartsky, D., E-mail: david.vartsky@weizmann.ac.il [Weizmann Institute of Science, Rehovot 76100 (Israel); Israelashvili, I. [Weizmann Institute of Science, Rehovot 76100 (Israel); Nuclear Research Center of Negev (NRCN), Beer-Sheva 9001 (Israel); Cortesi, M. [National Superconducting Cyclotron Laboratory, East Lansing 48823, MI (United States); Arazi, L.; Coimbra, A.E.; Moleri, L.; Erdal, E.; Bar, D.; Rappaport, M.; Shchemelinin, S. [Weizmann Institute of Science, Rehovot 76100 (Israel); Caspi, E.N. [Nuclear Research Center of Negev (NRCN), Beer-Sheva 9001 (Israel); Aviv, O. [Soreq NRC, Yavne 81800 (Israel); Breskin, A. [Weizmann Institute of Science, Rehovot 76100 (Israel)

    2016-07-11

    We describe progress made with a liquid-Xe (LXe) detector coupled to a gaseous photomultiplier (GPM), for combined imaging and spectroscopy of fast neutrons and gamma-rays in the MeV range. The purpose of this detector is to enable the detection of hidden explosives and fissile materials in cargo and containers. The expected position resolution is about 2 m and 3.5 mm for fast neutrons and gamma-rays, respectively. Experimental results obtained using an {sup 241}Am source yielded energy and time resolutions of 11% and 1.2 ns RMS, respectively. Initial results obtained with the position-sensitive GPM are presented.

  12. Aspects of HF radio propagation

    Directory of Open Access Journals (Sweden)

    Stephane Saillant

    2009-06-01

    Full Text Available

    radio systems. From the point of view Working Group 2 of the COST 296 Action, interest lies with effects associated

    with propagation via the ionosphere of signals within the HF band. Several aspects are covered in this paper:

    a The directions of arrival and times of flight of signals received over a path oriented along the trough have

    been examined and several types of propagation effects identified. Of particular note, combining the HF observations

    with satellite measurements has identified the presence of irregularities within the floor of the trough that

    result in propagation displaced from the great circle direction. An understanding of the propagation effects that

    result in deviations of the signal path from the great circle direction are of particular relevance to the operation

    of HF radiolocation systems.

    b Inclusion of the results from the above mentioned measurements into a propagation model of the northerly

    ionosphere (i.e. those regions of the ionosphere located poleward of, and including, the mid-latitude trough

    and the use of this model to predict the coverage expected from transmitters where the signals impinge on the

    northerly ionosphere

  13. Benchmarking of measurement and simulation of transverse rms-emittance growth

    Science.gov (United States)

    Groening, L.; Barth, W.; Bayer, W.; Clemente, G.; Dahl, L.; Forck, P.; Gerhard, P.; Hofmann, I.; Riehl, G.; Yaramyshev, S.; Jeon, D.; Uriot, D.

    2008-09-01

    Transverse emittance growth along the Alvarez drift tube linac (DTL) section is a major concern with respect to the preservation of beam quality of high current beams at the GSI UNILAC. In order to define measures to reduce this growth, appropriate tools to simulate the beam dynamics are indispensable. This paper is about the benchmarking of three beam dynamics simulation codes, i.e. DYNAMION, PARMILA, and PARTRAN against systematic measurements of beam emittances for different transverse phase advances along the DTL. Special emphasis is put on the modeling of the initial distribution for the simulations. The concept of rms equivalence is expanded from full intensity to fractions of less than 100% of the beam. The experimental setup, data reduction, preparation of the simulations, and the evaluation of the simulations are described. In the experiments and in the simulations, a minimum of the rms-emittance growth was observed at zero current phase advances of about 60°. In general, good agreement was found between simulations and experiment for the mean values of horizontal and vertical emittances at the DTL exit.

  14. The RMS Survey: Ammonia and water maser analysis of massive star forming regions

    CERN Document Server

    Urquhart, J S; Figura, C C; Moore, T J T; Lumsden, S L; Hoare, M G; Oudmaijer, R D; Mottram, J C; Davies, B; Dunham, M K

    2011-01-01

    The Red MSX Source (RMS) survey has identified a sample of ~1200 massive young stellar objects (MYSOs), compact and ultra compact HII regions from a sample of ~2000 MSX and 2MASS colour selected sources. We have used the 100 m Green Bank telescope to search for 22-24 GHz water maser and ammonia (1,1), (2,2) and (3,3) emission towards ~600 RMS sources located within the northern Galactic plane. We have identified 308 H2O masers which corresponds to an overall detection rate of ~50%. Abridged: We detect ammonia emission towards 479 of these massive young stars, which corresponds to ~80%. Ammonia is an excellent probe of high density gas allowing us to measure key parameters such as gas temperatures, opacities, and column densities, as well as providing an insight into the gas kinematics. The average kinetic temperature, FWHM line width and total NH3 column density for the sample are approximately 22 K, 2 km/s and 2x10^{15} cm^{-2}, respectively. We find that the NH3 (1,1) line width and kinetic temperature are ...

  15. The RMS Survey: Far-Infrared Photometry of Young Massive Stars

    CERN Document Server

    Mottram, J C; Lumsden, S L; Oudmaijer, R D; Urquhart, J S; Meade, M R; Moore, T J T; Stead, J J

    2009-01-01

    Context: The Red MSX Source (RMS) survey is a multi-wavelength campaign of follow-up observations of a colour-selected sample of candidate massive young stellar objects (MYSOs) in the galactic plane. This survey is returning the largest well-selected sample of MYSOs to date, while identifying other dust contaminant sources with similar mid-infrared colours including a large number of new ultra-compact (UC)HII regions. Aims:To measure the far-infrared (IR) flux, which lies near the peak of the spectral energy distribution (SED) of MYSOs and UCHII regions, so that, together with distance information, the luminosity of these sources can be obtained. Methods:Less than 50% of RMS sources are associated with IRAS point sources with detections at 60 micron and 100 micron, though the vast majority are visible in Spitzer MIPSGAL or IRAS Galaxy Atlas (IGA) images. However, standard aperture photometry is not appropriate for these data due to crowding of sources and strong spatially variable far-IR background emission i...

  16. Gaseous Detectors: Charged Particle Detectors - Particle Detectors and Detector Systems

    CERN Document Server

    Hilke, H J

    2011-01-01

    Gaseous Detectors in 'Charged Particle Detectors - Particle Detectors and Detector Systems', part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B1: Detectors for Particles and Radiation. Part 1: Principles and Methods'. This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Subsection '3.1.2 Gaseous Detectors' of Section '3.1 Charged Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.1.2 Gaseous Detectors 3.1.2.1 Introduction 3.1.2.2 Basic Processes 3.1.2.2.1 Gas ionization by charged particles 3.1.2.2.1.1 Primary clusters 3.1.2.2.1.2 Cluster size distribution 3.1.2.2.1.3 Total number of ion pairs 3.1.2.2.1.4 Dependence of energy deposit on particle velocity 3.1.2.2.2 Transport of...

  17. Integration of the Shuttle RMS/CBM Positioning Virtual Environment Simulation

    Science.gov (United States)

    Dumas, Joseph D.

    1996-01-01

    Constructing the International Space Station, or other structures, in space presents a number of problems. In particular, payload restrictions for the Space Shuttle and other launch mechanisms prohibit assembly of large space-based structures on Earth. Instead, a number of smaller modules must be boosted into orbit separately and then assembled to form the final structure. The assembly process is difficult, as docking interfaces such as Common Berthing Mechanisms (CBMS) must be precisely positioned relative to each other to be within the "capture envelope" (approximately +/- 1 inch and +/- 0.3 degrees from the nominal position) and attach properly. In the case of the Space Station, the docking mechanisms are to be positioned robotically by an astronaut using the 55-foot-long Remote Manipulator System (RMS) robot arm. Unfortunately, direct visual or video observation of the placement process is difficult or impossible in many scenarios. One method that has been tested for aligning the CBMs uses a boresighted camera mounted on one CBM to view a standard target on the opposing CBM. While this method might be sufficient to achieve proper positioning with considerable effort, it does not provide a high level of confidence that the mechanisms have been placed within capture range of each other. It also does nothing to address the risk of inadvertent contact between the CBMS, which could result in RMS control software errors. In general, constraining the operator to a single viewpoint with few, if any, depth cues makes the task much more difficult than it would be if the target could be viewed in three-dimensional space from various viewpoints. The actual work area could be viewed by an astronaut during EVA; however, it would be extremely impractical to have an astronaut control the RMS while spacewalking. On the other hand, a view of the RMS and CBMs to be positioned in a virtual environment aboard the Space Shuttle orbiter or Space Station could provide similar benefits

  18. The rms-flux relation in accreting white dwarfs: another nova-like variable and the first dwarf nova

    CERN Document Server

    Van de Sande, M; Knigge, C

    2015-01-01

    We report on the detection of the linear rms-flux relation in two accreting white dwarf binary systems: V1504 Cyg and KIC 8751494. The rms-flux relation relates the absolute root-mean-square (rms) variability of the light curve to its mean flux. The light curves analysed were obtained with the Kepler satellite at a 58.8 s cadence. The rms-flux relation was previously detected in only one other cataclysmic variable, MV Lyr. This result reenforces the ubiquity of the linear rms-flux relation as a characteristic property of accretion-induced variability, since it has been observed in several black hole binaries, neutron star binaries and active galactic nuclei. Moreover, its detection in V1504 Cyg is the first time the rms-flux relation has been detected in a dwarf nova-type CV during quiescence. This result, together with previous studies, hence points towards a common physical origin of accretion-induced variability, independent of the size, mass, or type of the central accreting compact object.

  19. HF Transverse Segmentation and Tagging Jet Capability

    CERN Document Server

    Doroshkevich, E A; Kuleshov, Sergey

    1998-01-01

    So called tagging jets and pile-up were simulated for the optimisation of the HF segmentation. The energy resolution, angular resolution and efficiency of jet reconstruction are defined for different calorimeter segmentation.

  20. Collisional quenching of highly rotationally excited HF

    CERN Document Server

    Yang, Benhui; Forrey, R C; Stancil, P C; Balakrishnan, N

    2015-01-01

    Collisional excitation rate coefficients play an important role in the dynamics of energy transfer in the interstellar medium. In particular, accurate rotational excitation rates are needed to interpret microwave and infrared observations of the interstellar gas for nonlocal thermodynamic equilibrium line formation. Theoretical cross sections and rate coefficients for collisional deexcitation of rotationally excited HF in the vibrational ground state are reported. The quantum-mechanical close-coupling approach implemented in the nonreactive scattering code MOLSCAT was applied in the cross section and rate coefficient calculations on an accurate 2D HF-He potential energy surface. Estimates of rate coefficients for H and H$_2$ colliders were obtained from the HF-He collisional data with a reduced-potential scaling approach. The calculation of state-to-state rotational quenching cross sections for HF due to He with initial rotational levels up to $j=20$ were performed for kinetic energies from 10$^{-5}$ to 15000...

  1. Microhardness evaluation alloys Hf-Si-B; Avaliacao de microdureza de ligas Hf-Si-B

    Energy Technology Data Exchange (ETDEWEB)

    Gigolotti, Joao Carlos Janio; Costa, Eliane Fernandes Brasil [Centro Universitario de Volta Redonda (UNIFOA), Volta Redonda, RJ (Brazil); Nunes, Carlos Angelo; Rocha, Elisa Gombio; Coelho, Gilberto Carvalho, E-mail: carlosjanio@uol.com.br, E-mail: eliane-costabrasi@hotmail.com, E-mail: cnunes@demar.eel.usp.br, E-mail: elisarocha@alunos.eel.usp.br, E-mail: coelho@demar.eel.usp.br [Universidade de Sao Paulo (USP), Lorena, SP (Brazil)

    2014-08-15

    The technological advance has generated increasing demand for materials that can be used under high temperature, what includes intermetallic MR-Si-B (MR = refractory metal) alloys with multiphase structures, that can also be applied in oxide environments. Thus, this work had for objective the micro hardness study of the Hf-Si-B system alloys, heat treated at 1600 deg C, in the Hf rich region. Hf-Si-B alloys had been produced with blades of Hf (min. 99.8%), Si (min. 99.998%) and B (min. 99.5%), in the voltaic arc furnace and heat treated at 1600 deg C under argon atmosphere. The relationship of the phases had been previously identified by X-ray diffraction and contrast in backscattered electron imaging mode. The alloys had their hardness analyzed by method Vickers (micro hardness) with load of 0.05 kgf and 0.2 kgf and application time of 20 s. The results, obtained from the arithmetic mean of measurements for each alloy on the heterogeneous region, showed a mean hardness of 11.08 GPA, with small coefficient of variation of 3.8%. The borides HfB2 (19.34 GPa) e HfB - 11.76 GPa, showed the hardness higher than the silicides Hf2Si (8.57 GPa), Hf5Si3 (9.63 GPa), Hf3Si2 (11.66 GPa), Hf5Si4 (10.00 GPa), HfSi (10.02 GPa) e HfSi2 (8.61 GPa). (author)

  2. Review: Rusticle Formation on the RMS Titanic and the Potential Influence of Oceanography

    Science.gov (United States)

    Salazar, Maxsimo; Little, Brenda

    2017-04-01

    Meter length iron-rich rusticles on the RMS Titanic contain bacteria that reportedly mobilize iron from the ship structure at a rate that will reduce the wreck to rust in decades. Other sunken ships, such as the World War II shipwrecks in the Gulf of Mexico (GOM) are also similarly covered. However, at the GOM sites, rusticles are only centimeters in length. Minimal differences in water temperature (a few °C) between the two sites and comparable exposure times from wreckage to discovery cannot rationalize the extreme differences in rusticle length. One possible explanation for the observed difference in rusticle size is the differing amounts of dissolved or colloidal iron at the two locations.

  3. Pixel Detectors

    OpenAIRE

    Wermes, Norbert

    2005-01-01

    Pixel detectors for precise particle tracking in high energy physics have been developed to a level of maturity during the past decade. Three of the LHC detectors will use vertex detectors close to the interaction point based on the hybrid pixel technology which can be considered the state of the art in this field of instrumentation. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as the very harsh...

  4. Surface current dynamics under sea breeze conditions observed by simultaneous HF radar, ADCP and drifter measurements

    Science.gov (United States)

    Sentchev, Alexei; Forget, Philippe; Fraunié, Philippe

    2017-02-01

    Ocean surface boundary layer dynamics off the southern coast of France in the NW Mediterranean is investigated by using velocity observations by high-frequency (HF) radars, surface drifting buoys and a downward-looking drifting acoustic Doppler current profiler (ADCP). The analysis confirms that velocities measured by HF radars correspond to those observed by an ADCP at the effective depth z f = k -1, where k is wavenumber of the radio wave emitted by the radar. The radials provided by the radars were in a very good agreement with in situ measurements, with the relative errors of 1 and 9 % and root mean square (RMS) differences of 0.02 and 0.04 m/s for monostatic and bistatic radar, respectively. The total radar-based velocities appeared to be slightly underestimated in magnitude and somewhat biased in direction. At the end of the survey period, the difference in the surface current direction, based on HF radar and ADCP data, attained 10°. It was demonstrated that the surface boundary layer dynamics cannot be reconstructed successfully without taking into the account velocity variation with depth. A significant misalignment of ˜30° caused by the sea breeze was documented between the HF radar (HFR-derived) surface current and the background current. It was also found that the ocean response to a moderate wind forcing was confined to the 4-m-thick upper layer. The respective Ekman current attained the maximum value of 0.15 m/s, and the current rotation was found to be lagging the wind by approximately 40 min, with the current vector direction being 15-20° to the left of the wind. The range of velocity variability due to wind forcing was found comparable with the magnitude of the background current variability.

  5. Emerging concepts on the anti-inflammatory actions of carbon monoxide-releasing molecules (CO-RMs

    Directory of Open Access Journals (Sweden)

    Motterlini Roberto

    2012-11-01

    Full Text Available Abstract Carbon monoxide-releasing molecules (CO-RMs are a class of organometallo compounds capable of delivering controlled quantities of CO gas to cells and tissues thus exerting a broad spectrum of pharmacological effects. CO-RMs containing transition metal carbonyls were initially implemented to mimic the function of heme oxygenase-1 (HMOX1, a stress inducible defensive protein that degrades heme to CO and biliverdin leading to anti-oxidant and anti-inflammatory actions. Ten years after their discovery, the research on the chemistry and biological activities of CO-RMs has greatly intensified indicating that their potential use as CO delivering agents for the treatment of several pathological conditions is feasible. Although CO-RMs are a class of compounds that structurally diverge from traditional organic-like pharmaceuticals, their behaviour in the biological environments is progressively being elucidated revealing interesting features of metal-carbonyl chemistry towards cellular targets. Specifically, the presence of carbonyl groups bound to transition metals such as ruthenium, iron or manganese appears to make CO-RMs unique in their ability to transfer CO intracellularly and amplify the mechanisms of signal transduction mediated by CO. In addition to their well-established vasodilatory activities and protective effects against organ ischemic damage, CO-RMs are emerging for their striking anti-inflammatory properties which may be the result of the multiple activities of metal carbonyls in the control of redox signaling, oxidative stress and cellular respiration. Here, we review evidence on the pharmacological effects of CO-RMs in models of acute and chronic inflammation elaborating on some emerging concepts that may help to explain the chemical reactivity and mechanism(s of action of this distinctive class of compounds in biological systems.

  6. Metal Detectors.

    Science.gov (United States)

    Harrington-Lueker, Donna

    1992-01-01

    Schools that count on metal detectors to stem the flow of weapons into the schools create a false sense of security. Recommendations include investing in personnel rather than hardware, cultivating the confidence of law-abiding students, and enforcing discipline. Metal detectors can be quite effective at afterschool events. (MLF)

  7. Optical Detectors

    Science.gov (United States)

    Tabbert, Bernd; Goushcha, Alexander

    Optical detectors are applied in all fields of human activities from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

  8. SU-8 as a Material for Microfabricated Particle Physics Detectors

    CERN Document Server

    Maoddi, Pietro; Jiguet, Sebastien; Renaud, Philippe

    2014-01-01

    Several recent detector te chnologies developed for particle physics applications are based on microfabricated structures. Dete ctors built with this approach generally exhibit the overall best performance in te rms of spatial and time resolution. Many properties of the SU-8 photoepoxy make it suitable for the manufacturing of microstructured particle detectors. This arti cle aims to review some emerging detector technologies making use of SU-8 microstructu ring, namely micropatte rn gaseous detectors and microfluidic scintillation detectors. Th e general working principle and main process steps for the fabrication of each device are reported, with a focus on the advantages brought to the device functionality by the us e of SU-8. A novel process based on multiple bonding steps for the fabrication of thin multila yer microfluidic scin tillation detectors developed by the authors is presented. Finally, a brief overview of the applications for the discussed devices is given.

  9. A study on the particle penetration in RMS Right Single Quotation Marks particle transport system

    Energy Technology Data Exchange (ETDEWEB)

    Son, S. M.; Oh, S. H.; Choi, C. R. [ELSOLTEC Inc., Youngin (Korea, Republic of)

    2014-10-15

    In nuclear facilities, a radiation monitoring system (RMS) monitors the exhaust gas containing the radioactive material. Samples of exhaust gas are collected in the downstream region of air cleaning units (ACUs) in order to examine radioactive materials. It is possible to predict an amount of radioactive material by analyzing the corrected samples. Representation of the collected samples should be assured in order to accurately sense and measure of radioactive materials. The radius of curvature is mainly 5 times of tube diameter. Sometimes, a booster fan is additionally added to enhance particle penetration rate... In this study, particle penetrations are calculated to evaluate particle penetration rate with various design parameters (tube lengths, tube declined angles, radius of curvatures, etc). The particle penetration rates have been calculated for several elements in the particle transport system. In general, the horizontal length of tube and the number of bending tube have a big impact on the penetration rate in the particle transport system. If the sampling location is far from the radiation monitoring system, additional installation of booster fans could be considered in case of large diameter tubes, but is not recommended in case of small diameter tube. In order to enhance particle penetration rate, the following works are recommended by priority. 1) to reduce the interval between sampling location and radiation monitoring system 2) to reduce the number of the bending tube.

  10. The RMS Survey: Near-IR Spectroscopy of Massive Young Stellar Objects

    CERN Document Server

    Cooper, H D B; Oudmaijer, R D; Hoare, M G; Clarke, A J; Urquhart, J S; Mottram, J C; Moore, T J T; Davies, B

    2013-01-01

    Near-infrared H- and K-band spectra are presented for 247 objects, selected from the Red MSX Source (RMS) survey as potential young stellar objects (YSOs). 195 (~80%) of the targets are YSOs, of which 131 are massive YSOs (L_BOL > 5x10^3 L_solar), M > 8M_solar. This is the largest spectroscopic study of massive YSOs to date, providing a valuable resource for the study of massive star formation. In this paper we present our exploratory analysis of the data. The YSOs observed have a wide range of embeddedness (2.7 < A_V < 114), demonstrating that this study covers minimally obscured objects right through to very red, dusty sources. Almost all YSOs show some evidence for emission lines, though there is a wide variety of observed properties. The most commonly detected lines are Brgamma, H_2, fluorescent FeII, CO bandhead, [FeII] and HeI 2-1 2^1S-2^1P, in order of frequency of occurrence. In total, ~40% of the YSOs display either fluorescent FeII 1.6878um or CO bandhead emission (or both), indicative of a ci...

  11. Chronic toluene exposure induces cell proliferation in the mice SVZ but not migration through the RMS.

    Science.gov (United States)

    Franco, Ireri; Valdez-Tapia, Mariana; Sanchez-Serrano, Sinthia L; Cruz, Silvia L; Lamas, Monica

    2014-07-11

    Abuse of toluene-containing inhalants is associated to various cognitive impairments that have been partly associated to deviation of the hippocampal neurogenesis processes during adulthood. In the present study we analyzed the effect of chronic toluene exposure (6000ppm) on cell proliferation and migration in the other selected area of the rodent brain where neurogenesis persist throughout adulthood, the subventricular zone of the lateral ventricle (SVZ). We used an anti-Ki67 antibody to evaluate SVZ cell proliferation, BrdU to evaluate cell survival and double-staining with BrdU and the migration marker doublecortin (DCX) to evaluate migration, by immunofluorescence 2h, 1, 5, 10 or 15 days after 20 sessions of toluene exposure. We found that toluene induced an initial burst of cell proliferation in the SVZ but not a significant increase in migration toward the rostral migratory stream (RMS) or the number of cells that migrate to the olfactory bulb. In addition, we detected a small number of new migrating cells in the corpus callosum and striatum of control mice that was similar in toluene-exposed brains. These results may underline the homeostatic capabilities of the populations of dividing cells, previously demonstrated using other drugs of abuse and demonstrate that toluene misuse can alter cellular proliferation in the postnatal brain. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. A distance limited sample of massive star forming cores from the RMS survey

    CERN Document Server

    Maud, L T; Moore, T J T; Mottram, J C; Urquhart, J S; Cicchini, A

    2015-01-01

    We analyse C$^{18}$O ($J=3-$2) data from a sample of 99 infrared-bright massive young stellar objects (MYSOs) and compact HII regions that were identified as potential molecular-outflow sources in the Red MSX source (RMS) survey. We extract a distance limited (D $<$ 6 kpc) sample shown to be representative of star formation covering the transition between the source types. At the spatial resolution probed, Larson-like relationships are found for these cores, though the alternative explanation, that Larson's relations arise where surface-density-limited samples are considered, is also consistent with our data. There are no significant differences found between source properties for the MYSOs and HII regions, suggesting that the core properties are established prior to the formation of massive stars, which subsequently have little impact at the later evolutionary stages investigated. There is a strong correlation between dust-continuum and C$^{18}$O-gas masses, supporting the interpretation that both trace t...

  13. Closeups of IECM grappled by RMS and positioned above payload bay (PLB)

    Science.gov (United States)

    1982-01-01

    Closeup view of the Marshall Space Flight Center (MSFC)-developed Induced Environment Contamination Monitor (IECM), a multi-instrument box designed to check for contaminants in and around the Space Shuttle orbiter payload bay (PLB) which might adversely affect delicate experiments onboard. The crew maneuvered the Canadian-built robot arm, called the remote manipulator system (RMS), very near their overhead flight deck windows and captured this scene with a 35mm camera. Cameras for the 11 instruments are the black circles. The access door to the arm and safe plug is located about halfway up the side of the box. A cascade injector device appears next to access door. The rectangular opening at center of the box is the optical effects module. Mass spectrometer is in one corner with air sampler bottles at the opposite corner. The colorful rectangle is the passive array. Not easily seen but also a part of the instrument, are Cryogenic Quartz Crystal Microbalance (CQCM) and the temperature co

  14. The RMS Survey: Critical Tests of Accretion Models for the Formation of Massive Stars

    CERN Document Server

    Davies, Ben; Lumsden, Stuart L; Hosokawa, Takashi; Oudmaijer, Rene D; Urquhart, James S; Mottram, Joseph C; Stead, Joseph

    2011-01-01

    There is currently no accepted theoretical framework for the formation of the most massive stars, and the manner in which protostars continue to accrete and grow in mass beyond \\sim10Msun is still a controversial topic. In this study we use several prescriptions of stellar accretion and a description of the Galactic gas distribution to simulate the luminosities and spatial distribution of massive protostellar population of the Galaxy. We then compare the observables of each simulation to the results of the Red MSX Source (RMS) survey, a recently compiled database of massive young stellar objects. We find that the observations are best matched by accretion rates which increase as the protostar grows in mass, such as those predicted by the turbulent core and competitive accretion (i.e. Bondi-Hoyle) models. These 'accelerating accretion' models provide very good qualitative and quantitative fits to the data, though we are unable to distinguish between these two models on our simulations alone. We rule out models...

  15. DUMAND detector

    CERN Multimedia

    This object is one of the 256 other detectors of the DUMAND (Deep Underwater Muon And Neutrino Detection) experiment. The goal of the experiment was the construction of the first deep ocean high energy neutrino detector, to be placed at 4800 m depth in the Pacific Ocean off Keahole Point on the Big Island of Hawaii. A few years ago, a European conference with Cosmic experiments was organized at CERN as they were projects like DUMAND in Hawaii. Along with the conference, a temporary exhibition was organised as well. It was a collaboration of institutions from Germany, Japan, Switzerland and the U.S.A. CERN had borrowed equipment and objects from different institutes around the world, including this detector of the DUMAND experiment. Most of the equipment were sent back to the institutes, however this detector sphere was offered to a CERN member of the personnel.

  16. Cross sections for medium energy He ions scattered from Hf and Au atoms

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tomoaki, E-mail: t-nishi@hosei.ac.jp [Research Center of Ion Beam Technology and College of Engineering, Hosei University, Koganei, Tokyo 184-8584 (Japan); Mitsuhara, Kei; Visikovskiy, Anton; Kido, Yoshiaki [Department of Physics, Ritsumeikan University, Kusatsu, Shiga-ken 525-8577 (Japan)

    2012-06-01

    The elastic scattering cross sections for medium energy He ions incident on Ni, Hf and Au atoms were measured precisely using a toroidal electrostatic analyzer. We prepared the targets of Ni({approx}1 nm)/HfO{sub 2}(1.5 nm)/Si(0 0 1) and Ni({approx}1 nm)/Au({approx}0.5 nm)/Si(1 1 1) and performed in situ ion scattering measurement under ultrahigh vacuum condition. The absolute amounts of Ni, Hf and Au were determined by Rutherford backscattering using 1.5 MeV He ions at a scattering angle of 150 Degree-Sign . The scattering cross sections for Hf and Au were normalized by those for Ni to avoid the ambiguities of the number of incident particles, solid angle subtended by a detector, detection efficiency and the He{sup +} fractions for the emerging He ions from the surfaces. The results obtained are compared with the simple Lee-Hart formula and the calculated values using the Moliere and ZBL potentials and the potentials derived from the Hartree-Fock-Slater wave functions.

  17. General concepts of modern HF communications

    Science.gov (United States)

    Aarons, Jules

    Both conceptual and hardware advancements have led to substantial systems developments in military HF communications; the former encompass coding and error correction techniques for security, in order to minimize propagation and interference, while the latter prominently include digital equipment permitting the selection of a frequency for a particular path and propagation mode, as well as modulation selection. Propagation-related advancements involve better statistical models as well as advancements in short-term forecasting methods responsive to changes in solar-geophysical parameters. Adaptive HF systems have been developed for meteor-scatter radio communications.

  18. Angular momentum limit of Hf isotopes produced in three fusion-evaporation reactions

    CERN Document Server

    Domscheit, J; Ernst, J; Fallon, P; Herskind, B; Hübel, H; Korten, W; Lee, I Y; Macchiavelli, A O; Nenoff, N; Siem, S; Ward, D; Wilson, J N

    2001-01-01

    The compound nucleus sup 1 sup 6 sup 8 Hf was populated in three fusion-evaporation reactions with different beam-target mass asymmetries: sup 5 sup 0 Ti+ sup 1 sup 1 sup 8 Sn, sup 6 sup 4 Ni+ sup 1 sup 0 sup 4 Ru and sup 7 sup 4 Ge+ sup 9 sup 4 Zr. Due to the large negative Q values of these reactions the compound nucleus is formed at low excitation energy. At three or four excitation energies for each reaction gamma-ray spectra of the evaporation residues sup 1 sup 6 sup 6 Hf to sup 1 sup 6 sup 3 Hf, corresponding to the 2n to 5n exit channels, respectively, were recorded with the Ge detectors of the 8 pi-spectrometer array. The gamma-ray multiplicity and total energy were measured using the inner ball of BGO detectors. This data was used to determine the maximum angular momentum transferred to each evaporation channel, the gamma-ray decay entry region and the relative cross sections. No differences are observed between the three reactions. This is explained by the very similar dependence of the excitation ...

  19. Research on Multi-Layer Distributed HF Radio Network Structure

    Institute of Scientific and Technical Information of China (English)

    Hui Dai; Chun-Jiang Wang; Quan Yu

    2008-01-01

    High frequency (HF) transmission is an important communication techniques. However, conventional point-to-point transmission can be easily destroyed, which limits its utilization in practice. HF networking communication has the capability against demolishment. The network structure is one of the key factors for HF networking communication. In this paper, a novel analysis method of the network connectedness based on the eigenvalue is derived, and a multi-layer distributed HF radio network structure is proposed. Both the theore tical analysis and the computer simulation results verify that the application of the proposed network structure in the HF radio communication can improve the anti demolishment ability of the HF network efficiently.

  20. Planarity certification of ATLAS Micromegas detector panels

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Ralph; Biebel, Otmar; Bortfeldt, Jonathan; Flierl, Bernhard; Hertenberger, Ralf; Loesel, Philipp; Herrmann, Maximilian [LMU Muenchen (Germany); Zibell, Andre [JMU Wuerzburg (Germany)

    2016-07-01

    During the second long LHC shutdown, 2019/20, the precision tracking detectors of the ATLAS muon spectrometer in the inner end caps will be replaced using Micromegas, a planar gas-detector technology. Modules of 2 m{sup 2} area are built in quadruplets from five precisely planar sandwich panels that define the anodes and the cathodes of the four active detector planes. A panel is composed of three consecutive layers FR4 - aluminum honeycomb - FR4. Single plane spatial particle resolution below 100 μm is achievable when the deviations from planarity of the strip-anodes do not exceed 80 μm RMS over the whole active area and the parallelism of the readout strips is within 30 μm. In order to measure the dimensional accuracy of each panel, laser distance sensors combined with a coordinate measurement system have been investigated. The sensor requirements to measure the planarity of the panels are a resolution of 0.3 μm and a beam spot diameter of ∼20 μm, well below 100 μ m the size of the smallest structures. We report on achieved planarities of the panels and the performance of the laser sensor system. A panel with an RMS better than 30 μm was build and the evolution of its planarity due to humidity and temperature effects is shown.

  1. Application of The Hydrology Lab Research Modeling System (hl-rms) For Large Headwater Catchments

    Science.gov (United States)

    Koren, V.; Smith, M.; Reed, S.; Zhang, Z.

    The Hydrology Lab (HL) of the National Weather Service Office of Hydrologic De- velopment is actively engaged in research and development into catchment modeling approaches to improve the ability to forecast river flows. Traditionally, conceptual lumped models have been used to produce operational river forecasts, and they of- ten produce reasonable results provided their parameters were calibrated properly. A common hypothesis in the scientific community attributes this success primarily to a model parameter calibration without regard a model structure. It is also commonly assumed that distributed models will provide better results just because they account for the spatial variability of input data and parameters. However, experience suggests that there are advantages and disadvantages of lumped and distributed models due to the combined effects of model structure and parameter estimation procedures. Neither physically poor models with advanced parameter estimation procedures, nor physi- cally advanced models with poor parameter estimation procedures can provide reason- able results. While most conceptual lumped models do not use explicitly the classical mass and momentum conservation equations, they incorporate strong physical con- cepts supported by field experiments. Their parameters represent integrated effects of basin properties on an outlet hydrograph, and as a result, they are identifiable from hydrograph analysis. On the other hand, most distributed models are based on point process equations, and distributed parameters are less identifiable from hydrograph analysis because they represent local properties. The authors believe that more com- prehensive analyses of lumped and distributed models on large-scale basins is needed to fully benefit from existing lumped modeling experience. As a Distributed Model Intercomparison Project (DMIP) initiative, HL has developed a grid-based Research Modeling System (HL-RMS) that combines lumped and distributed model

  2. Electrical study of Al/HfO2/p-Si (100) gate stack

    Science.gov (United States)

    Kumar, Arvind; Mondal, Sandip; Rao, K. S. R. Koteswara

    2016-05-01

    Low leakage current density and high relative permittivity (dielectric constant) are the key factors in order to replace the SiO2 from Si based technology towards its further down scaling. HfO2 thin films received significant attention due to its excellent optoelectronic properties. In this work, ultra - thin (17 nm) HfO2 films on Si substrate are fabricated by RF sputtering. As deposited films are amorphous in nature and in order to get the reasonable high dielectric constant the films are annealed (700°C, 30 min) in nitrogen environment. A high refractive index (2.08) and small grain size (~10) nm was extracted from ellipsometry and XRD, respectively. The AFM study revealed a small RMS surface roughness 9 Å. Towards electrical exploration, the films are integrated in Metal - Insulator - Semiconductor (MIS) capacitors structure. The oxide capacitance (Cox), flat band capacitance (CFB), flat band voltage (VFB), and oxide trapped charges (Qot) calculated from high frequency (1 MHz) C-V curve are 490 pF, 183 pF, 1.33 V and 1.61x10-10 C, respectively. The dielectric constant calculated from accumulation capacitance is 17. The films show a very low leakage current density 4.3×10-8 A/cm2 at ±1 V.

  3. Global coordination and standardisation in marine biodiversity through the World Register of Marine Species (WoRMS and related databases.

    Directory of Open Access Journals (Sweden)

    Mark J Costello

    Full Text Available The World Register of Marine Species is an over 90% complete open-access inventory of all marine species names. Here we illustrate the scale of the problems with species names, synonyms, and their classification, and describe how WoRMS publishes online quality assured information on marine species. Within WoRMS, over 100 global, 12 regional and 4 thematic species databases are integrated with a common taxonomy. Over 240 editors from 133 institutions and 31 countries manage the content. To avoid duplication of effort, content is exchanged with 10 external databases. At present WoRMS contains 460,000 taxonomic names (from Kingdom to subspecies, 368,000 species level combinations of which 215,000 are currently accepted marine species names, and 26,000 related but non-marine species. Associated information includes 150,000 literature sources, 20,000 images, and locations of 44,000 specimens. Usage has grown linearly since its launch in 2007, with about 600,000 unique visitors to the website in 2011, and at least 90 organisations from 12 countries using WoRMS for their data management. By providing easy access to expert-validated content, WoRMS improves quality control in the use of species names, with consequent benefits to taxonomy, ecology, conservation and marine biodiversity research and management. The service manages information on species names that would otherwise be overly costly for individuals, and thus minimises errors in the application of nomenclature standards. WoRMS' content is expanding to include host-parasite relationships, additional literature sources, locations of specimens, images, distribution range, ecological, and biological data. Species are being categorised as introduced (alien, invasive, of conservation importance, and on other attributes. These developments have a multiplier effect on its potential as a resource for biodiversity research and management. As a consequence of WoRMS, we are witnessing improved

  4. Global coordination and standardisation in marine biodiversity through the World Register of Marine Species (WoRMS) and related databases.

    Science.gov (United States)

    Costello, Mark J; Bouchet, Philippe; Boxshall, Geoff; Fauchald, Kristian; Gordon, Dennis; Hoeksema, Bert W; Poore, Gary C B; van Soest, Rob W M; Stöhr, Sabine; Walter, T Chad; Vanhoorne, Bart; Decock, Wim; Appeltans, Ward

    2013-01-01

    The World Register of Marine Species is an over 90% complete open-access inventory of all marine species names. Here we illustrate the scale of the problems with species names, synonyms, and their classification, and describe how WoRMS publishes online quality assured information on marine species. Within WoRMS, over 100 global, 12 regional and 4 thematic species databases are integrated with a common taxonomy. Over 240 editors from 133 institutions and 31 countries manage the content. To avoid duplication of effort, content is exchanged with 10 external databases. At present WoRMS contains 460,000 taxonomic names (from Kingdom to subspecies), 368,000 species level combinations of which 215,000 are currently accepted marine species names, and 26,000 related but non-marine species. Associated information includes 150,000 literature sources, 20,000 images, and locations of 44,000 specimens. Usage has grown linearly since its launch in 2007, with about 600,000 unique visitors to the website in 2011, and at least 90 organisations from 12 countries using WoRMS for their data management. By providing easy access to expert-validated content, WoRMS improves quality control in the use of species names, with consequent benefits to taxonomy, ecology, conservation and marine biodiversity research and management. The service manages information on species names that would otherwise be overly costly for individuals, and thus minimises errors in the application of nomenclature standards. WoRMS' content is expanding to include host-parasite relationships, additional literature sources, locations of specimens, images, distribution range, ecological, and biological data. Species are being categorised as introduced (alien, invasive), of conservation importance, and on other attributes. These developments have a multiplier effect on its potential as a resource for biodiversity research and management. As a consequence of WoRMS, we are witnessing improved communication within the

  5. Efficient Solar Scene Wavefront Estimation with Reduced Systematic and RMS Errors: Summary

    Science.gov (United States)

    Anugu, N.; Garcia, P.

    2016-04-01

    Wave front sensing for solar telescopes is commonly implemented with the Shack-Hartmann sensors. Correlation algorithms are usually used to estimate the extended scene Shack-Hartmann sub-aperture image shifts or slopes. The image shift is computed by correlating a reference sub-aperture image with the target distorted sub-aperture image. The pixel position where the maximum correlation is located gives the image shift in integer pixel coordinates. Sub-pixel precision image shifts are computed by applying a peak-finding algorithm to the correlation peak Poyneer (2003); Löfdahl (2010). However, the peak-finding algorithm results are usually biased towards the integer pixels, these errors are called as systematic bias errors Sjödahl (1994). These errors are caused due to the low pixel sampling of the images. The amplitude of these errors depends on the type of correlation algorithm and the type of peak-finding algorithm being used. To study the systematic errors in detail, solar sub-aperture synthetic images are constructed by using a Swedish Solar Telescope solar granulation image1. The performance of cross-correlation algorithm in combination with different peak-finding algorithms is investigated. The studied peak-finding algorithms are: parabola Poyneer (2003); quadratic polynomial Löfdahl (2010); threshold center of gravity Bailey (2003); Gaussian Nobach & Honkanen (2005) and Pyramid Bailey (2003). The systematic error study reveals that that the pyramid fit is the most robust to pixel locking effects. The RMS error analysis study reveals that the threshold centre of gravity behaves better in low SNR, although the systematic errors in the measurement are large. It is found that no algorithm is best for both the systematic and the RMS error reduction. To overcome the above problem, a new solution is proposed. In this solution, the image sampling is increased prior to the actual correlation matching. The method is realized in two steps to improve its

  6. HEXITEC ASIC-a pixellated readout chip for CZT detectors

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence [STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)], E-mail: l.l.jones@stfc.ac.uk; Seller, Paul; Wilson, Matthew; Hardie, Alec [STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)

    2009-06-01

    HEXITEC is a collaborative project with the aim of developing a new range of detectors for high-energy X-ray imaging. High-energy X-ray imaging has major advantages over current lower energy imaging for the life and physical sciences, including improved phase-contrast images on larger, higher density samples and with lower accumulated doses. However, at these energies conventional silicon-based devices cannot be used, hence, the requirement for a new range of high Z-detector materials. Underpinning the HEXITEC programme are the development of a pixellated Cadmium Zinc Telluride (CZT) detectors and a pixellated readout ASIC which will be bump-bonded to the detector. The HEXITEC ASIC is required to have low noise (20 electrons rms) and tolerate detector leakage currents. A prototype 20x20 pixel ASIC has been developed and manufactured on a standard 0.35 {mu}m CMOS process.

  7. HEXITEC ASIC—a pixellated readout chip for CZT detectors

    Science.gov (United States)

    Jones, Lawrence; Seller, Paul; Wilson, Matthew; Hardie, Alec

    2009-06-01

    HEXITEC is a collaborative project with the aim of developing a new range of detectors for high-energy X-ray imaging. High-energy X-ray imaging has major advantages over current lower energy imaging for the life and physical sciences, including improved phase-contrast images on larger, higher density samples and with lower accumulated doses. However, at these energies conventional silicon-based devices cannot be used, hence, the requirement for a new range of high Z-detector materials. Underpinning the HEXITEC programme are the development of a pixellated Cadmium Zinc Telluride (CZT) detectors and a pixellated readout ASIC which will be bump-bonded to the detector. The HEXITEC ASIC is required to have low noise (20 electrons rms) and tolerate detector leakage currents. A prototype 20×20 pixel ASIC has been developed and manufactured on a standard 0.35 μm CMOS process.

  8. Combinatorial approach to MgHf co-doped AlN thin films for Vibrational Energy Harvesters

    Science.gov (United States)

    Nguyen, H. H.; Oguchi, H.; Kuwano, H.

    2016-11-01

    In this report, we studied MgHf co-doped AlN ((Mg,Hf)xA11-xN) aiming for developing an AlN-based dielectric material with the large piezoelectric coefficient. To rapidly screen the wide range of composition, we applied combinatorial film growth approach. To get continuous composition gradient on a single substrate, films were deposited on Si (100) substrates by sputtering AlN and Mg-Hf targets simultaneously. Crystal structure was investigated by X-ray diffractometer equipped with a two-dimensional detector (2D-XRD). Composition was determined by Energy Dispersive Spectroscopy (EDS). These studies revealed that we successfully covered the widest ever composition range of 0 x x = 0.24, which will lead to the highest enhancement in the piezoelectric coefficient. The results of this study opened the way for high-throughput development of the dielectric materials.

  9. Systematic Comparison of HF CMOS Transconductors

    NARCIS (Netherlands)

    Klumperink, Eric A.M.; Nauta, Bram

    2003-01-01

    Transconductors are commonly used as active elements in high-frequency (HF) filters, amplifiers, mixers, and oscillators. This paper reviews transconductor design by focusing on the V-I kernel that determines the key transconductor properties. Based on bandwidth considerations, simple V-I kernels wi

  10. Electron impact on vibrationally cold {{HF}}^{+}

    Science.gov (United States)

    Cristian Stroe, Marius; Fifirig, Magda

    2016-12-01

    The dissociative recombination and vibrational excitation processes induced by electron impact on vibrationally cold {{HF}}+ are investigated in the framework of the multichannel quantum defect theory for electron energies below 1 eV. The thermal rate coefficients for the electron temperature range from 10 to 5000 K are reported.

  11. ORIGIN OF EXCESS (176)Hf IN METEORITES

    DEFF Research Database (Denmark)

    Thrane, Kristine; Connelly, James Norman; Bizzarro, Martin

    2010-01-01

    After considerable controversy regarding the (176)Lu decay constant (lambda(176)Lu), there is now widespread agreement that (1.867 +/- 0.008) x 10(-11) yr(-1) as confirmed by various terrestrial objects and a 4557 Myr meteorite is correct. This leaves the (176)Hf excesses that are correlated with...

  12. Imaging characteristics of the Extreme Ultraviolet Explorer microchannel plate detectors

    Science.gov (United States)

    Vallerga, J. V.; Kaplan, G. C.; Siegmund, O. H. W.; Lampton, M.; Malina, R. F.

    1989-01-01

    The Extreme Ultraviolet Explorer (EUVE) satellite will conduct an all-sky survey over the wavelength range from 70 A to 760 A using four grazing-incidence telescopes and seven microchannel-plate (MCP) detectors. The imaging photon-counting MCP detectors have active areas of 19.6 cm2. Photon arrival position is determined using a wedge-and-strip anode and associated pulse-encoding electronics. The imaging characteristics of the EUVE flight detectors are presented including image distortion, flat-field response, and spatial differential nonlinearity. Also included is a detailed discussion of image distortions due to the detector mechanical assembly, the wedge-and-strip anode, and the electronics. Model predictions of these distortions are compared to preflight calibration images which show distortions less than 1.3 percent rms of the detector diameter of 50 mm before correction. The plans for correcting these residual detector image distortions to less than 0.1 percent rms are also presented.

  13. Calorimeter detectors

    CERN Document Server

    de Barbaro, P; The ATLAS collaboration

    2013-01-01

    Although the instantaneous and integrated luminosity in HL-LHC will be far higher than the LHC detectors were originally designed for, the Barrel calorimeters of the four experiments are expected to continue to perform well  throughout the Phase II program. The conditions for the End-Cap calorimeters are far more challenging and whilst some detectors will require relatively modest changes, others require far more substantial upgrades. We present the results of longevity and performance studies for the calorimeter systems of the four main LHC experiments and outline the upgrade options under consideration. We include a discussion of the R&D required to make the final technology choices for the upgraded detectors.

  14. Pixel detectors

    CERN Document Server

    Passmore, M S

    2001-01-01

    positions on the detector. The loss of secondary electrons follows the profile of the detector and increases with higher energy ions. studies of the spatial resolution predict a value of 5.3 lp/mm. The image noise in photon counting systems is investigated theoretically and experimentally and is shown to be given by Poisson statistics. The rate capability of the LAD1 was measured to be 250 kHz per pixel. Theoretical and experimental studies of the difference in contrast for ideal charge integrating and photon counting imaging systems were carried out. It is shown that the contrast differs and that for the conventional definition (contrast = (background - signal)/background) the photon counting device will, in some cases, always give a better contrast than the integrating system. Simulations in MEDICI are combined with analytical calculations to investigate charge collection efficiencies (CCE) in semiconductor detectors. Different pixel sizes and biasing conditions are considered. The results show charge shari...

  15. XMASS detector

    CERN Document Server

    Abe, K; Hiraide, K; Hirano, S; Kishimoto, Y; Kobayashi, K; Moriyama, S; Nakagawa, K; Nakahata, M; Nishiie, H; Ogawa, H; Oka, N; Sekiya, H; Shinozaki, A; Suzuki, Y; Takeda, A; Takachio, O; Ueshima, K; Umemoto, D; Yamashita, M; Yang, B S; Tasaka, S; Liu, J; Martens, K; Hosokawa, K; Miuchi, K; Murata, A; Onishi, Y; Otsuka, Y; Takeuchi, Y; Kim, Y H; Lee, K B; Lee, M K; Lee, J S; Fukuda, Y; Itow, Y; Nishitani, Y; Masuda, K; Takiya, H; Uchida, H; Kim, N Y; Kim, Y D; Kusaba, F; Motoki, D; Nishijima, K; Fujii, K; Murayama, I; Nakamura, S

    2013-01-01

    The XMASS project aims to detect dark matter, pp and $^{7}$Be solar neutrinos, and neutrinoless double beta decay using ultra pure liquid xenon. The first phase of the XMASS experiment searches for dark matter. In this paper, we describe the XMASS detector in detail, including its configuration, data acquisition equipment and calibration system.

  16. XMASS detector

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hieda, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Hiraide, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hirano, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kishimoto, Y.; Kobayashi, K.; Moriyama, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nakagawa, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Nakahata, M. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nishiie, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Ogawa, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, the University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); and others

    2013-07-11

    The XMASS project aims to detect dark matter, pp and {sup 7}Be solar neutrinos, and neutrinoless double beta decay using ultra pure liquid xenon. The first phase of the XMASS experiment searches for dark matter. In this paper, we describe the XMASS detector in detail, including its configuration, data acquisition equipment and calibration system.

  17. A passivity based control methodology for flexible joint robots with application to a simplified shuttle RMS arm

    Science.gov (United States)

    Sicard, Pierre; Wen, John T.

    1991-01-01

    The main goal is to develop a general theory for the control of flexible robots, including flexible joint robots, flexible link robots, rigid bodies with flexible appendages, etc. As part of the validation, the theory is applied to the control law development for a test example which consists of a three-link arm modeled after the shoulder yaw joint of the space shuttle remote manipulator system (RMS). The performance of the closed loop control system is then compared with the performance of the existing RMS controller to demonstrate the effectiveness of the proposed approach. The theoretical foundation of this new approach to the control of flexible robots is presented and its efficacy is demonstrated through simulation results on the three-link test arm.

  18. The RMS Survey: Resolving kinematic distance ambiguities towards a sample of compact HII regions using HI absorption

    CERN Document Server

    Urquhart, J S; Lumsden, S L; Oudmaijer, R D; Moore, T J T; Mottram, J C; Cooper, H D B; Mottram, M; Rogers, H C

    2011-01-01

    We present high-resolution HI data obtained using the Australia Telescope Compact Array to resolve the near/far distance ambiguities towards a sample of compact HII regions from the Red MSX Source (RMS) survey. The high resolution data are complemented with lower resolution archival HI data extracted from the Southern and VLA Galactic Plane surveys. We resolve the distance ambiguity for nearly all of the 105 sources where the continuum was strong enough to allow analysis of the HI absorption line structure. This represents another step in the determination of distances to the total RMS sample, which with over 1,000 massive young stellar objects and compact HII regions, is the largest and most complete sample of its kind. The full sample will allow the distribution of massive star formation in the Galaxy to be examined.

  19. A novel approach for pulse width measurements with a high precision (8 ps RMS) TDC in an FPGA

    Science.gov (United States)

    Ugur, C.; Linev, S.; Michel, J.; Schweitzer, T.; Traxler, M.

    2016-01-01

    High precision time measurements are a crucial element in particle identification experiments, which likewise require pulse width information for Time-over-Threshold (ToT) measurements and charge measurements (correlated with pulse width). In almost all of the FPGA-based TDC applications, pulse width measurements are implemented using two of the TDC channels for leading and trailing edge time measurements individually. This method however, requires twice the number of resources. In this paper we present the latest precision improvements in the high precision TDC (8 ps RMS) developed before [1], as well as the novel way of measuring ToT using a single TDC channel, while still achieving high precision (as low as 11.7 ps RMS). The effect of voltage, generated by a DC-DC converter, over the precision is also discussed. Finally, the outcome of the temperature change over the pulse width measurement is shown and a correction method is suggested to limit the degradation.

  20. Implementation of a high resolution (< 11 ps RMS) Time-to-Digital Converter in a Field Programmable Gate Array

    Energy Technology Data Exchange (ETDEWEB)

    Ugur, Cahit [Helmholtz-Institut Mainz, Johannes Gutenberg-Universitaet Mainz (Germany); Bayer, Eugen [Department for Digital Electronics, University Kassel (Germany); Kurz, Nikolaus; Traxler, Michael [GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Michel, Jan [Institute for Nuclear Physics, Goethe University Frankfurt, Frankfurt am Main (Germany)

    2012-07-01

    A high resolution time-to-digital converter (TDC) was implemented in a general purpose field-programmable gate array (FPGA), a re-programmable digital chip. RMS and the time resolution of different channels are calculated for one clock cycle (5 ns) interval and a minimum of 10.3 ps RMS on two channels is achieved, which yields to a time resolution of 7.3 ps (10.3 ps/{radical}(2)) on a single channel. The TDC can be used in time-of-flight, time-over-threshold, drift time measurement applications as well as many other measurements with specific Front-End Electronics (FEE), e.g. charge measurements with charge-to-width (Q2W) FEE. The re-programmable flexibility of FPGAs also allows to have application specific features, e.g. trigger window, zero dead time etc.

  1. REMPI Spectroscopy of HfF

    CERN Document Server

    Loh, Huanqian; Yahn, Tyler S; Looser, Herbert; Field, Robert W; Cornell, Eric A

    2012-01-01

    The spectrum of electronic states at 30000--33000 cm$^{-1}$ in hafnium fluoride has been studied using (1+1) resonance-enhanced multi-photon ionization (REMPI) and (1+1$'$) REMPI. Six $\\Omega' = 3/2$ and ten $\\Pi_{1/2}$ vibronic bands have been characterized. We report the molecular constants for these bands and estimate the electronic energies of the excited states using a correction derived from the observed isotope shifts. When either of two closely spaced $\\Pi_{1/2}$ electronic states is used as an intermediate state to access autoionizing Rydberg levels, qualitatively distinct autoionization spectra are observed. The intermediate state-specificity of the autoionization spectra bodes well for the possibility of using a selected $\\Pi_{1/2}$ state as an intermediate state to create ionic HfF$^+$ in various selected quantum states, an important requirement for our electron electric dipole moment (eEDM) search in HfF$^+$.

  2. COMMISSIONING AND DETECTOR PERFORMANCE GROUPS

    CERN Multimedia

    T. Camporesi

    P5 Commissioning activities The commissioning effort at the pit has made major progress since the last CMS week concerning the installation and operation of the off-detector electronics in USC. The progress has been much slower in the experi¬mental cavern due to the delay in the deployment of the infrastructure which should eventually allow safe powering-up of the front ends. Nevertheless, temporary power connections have allowed operation of slices of subdetectors at any given time. HF, HE, ECAL, DTs, RPCs and CSCs have carried out local commissioning tests with these temporary services. The status of hardware deployment in USC and on the towers/balconies is represented in the detailed table below.   Table 1: Status of installation of off-detector electronics. FEDs are detector dependent hardware modules which perform the first ‘colla¬tion’ of front-end data and send it to Central-data for event building. Tracker, ECAL, HCAL have their front end electronics mo...

  3. Visit at PFAFF Silberblau for follow -up of mechanical jacks fabrication for HF

    CERN Multimedia

    Hubert Gerwig

    2000-01-01

    The HF detctor is sitting on either side of the CMS experiment at a height of the beam, 8.79m This detector weighs 220 tons will be lifted in 4 steps on its working position. 4 mechanical jacks with 100t force each will act on each corner of rectangle of 5600mm x 3200mm. The individual main pieces of the jacks are shown here. Next step is the assembly of the jacks by putting together housing, groundplate, spindle, gear, worm gear etc. Delivery of the first 4 jacks in dec.2000

  4. Digitally Driven Antenna for HF Transmission

    Science.gov (United States)

    2010-09-01

    the 1-MHz carrier signal. This signal is then fed into the base terminals of an NPN/ PNP transistor pair arranged in a push–pull configura- tion. A dual...negative voltage connected to the collector terminal of the PNP transistor . Since it was not possible to explicitly simulate the radia- tion of the time...complementary pair of switching transistors is driven with a pulsewidth modulated HF signal, eliminating the requirement for a frequency-dependent

  5. RFID UHF i HF w bibliotekach

    Directory of Open Access Journals (Sweden)

    Gładysz Bartłomiej

    2015-06-01

    Full Text Available The potential of the innovative Radio Frequency Identification (RFID technology to be applied for support, acceleration and automation of the circulation process of library collection is presented. Technology basics, and hardware and software components are described. Two different radio standards used in libraries are compared. The goal is to present the potential of RFID technology for libraries, to highlight the differences and to build a basis for further consideration of UHF and HF alternatives.

  6. Semiconductor Detectors; Detectores de Semiconductores

    Energy Technology Data Exchange (ETDEWEB)

    Cortina, E.

    2007-07-01

    Particle detectors based on semiconductor materials are among the few devices used for particle detection that are available to the public at large. In fact we are surrounded by them in our daily lives: they are used in photoelectric cells for opening doors, in digital photographic and video camera, and in bar code readers at supermarket cash registers. (Author)

  7. Plasma panel-based radiation detectors

    CERN Document Server

    Friedman, Peter; Beene, James; Benhammou, Yan; Ben-Moshe, Meny; Bentefour, Hassan; Chapman, J W; Etzion, Erez; Ferretti, Claudio; Levin, Daniel; Silver, Yiftah; Varner, Robert; Weaverdyck, Curtis; Zhou, Bing; 10.1002/jsid.151

    2013-01-01

    The plasma panel sensor (PPS) is a gaseous micropattern radiation detector under current development. It has many operational and fabrication principles common to plasma display panels. It comprises a dense matrix of small, gas plasma discharge cells within a hermetically sealed panel. As in plasma display panels, it uses nonreactive, intrinsically radiation-hard materials such as glass substrates, refractory metal electrodes, and mostly inert gas mixtures. We are developing these devices primarily as thin, low-mass detectors with gas gaps from a few hundred microns to a few millimeters. The PPS is a high gain, inherently digital device with the potential for fast response times, fine position resolution (<50-mm RMS) and low cost. In this paper, we report on prototype PPS experimental results in detecting betas, protons, and cosmic muons, and we extrapolate on the PPS potential for applications including the detection of alphas, heavy ions at low-to-medium energy, thermal neutrons, and X-rays.

  8. Mass Measurements of AGN from Multi-Lorentzian Models of X-ray Variability. I. Sampling Effects in Theoretical Models of the rms^2-M_BH Correlation

    DEFF Research Database (Denmark)

    Pessah, Martin Elias

    2006-01-01

    Recent X-ray variability studies suggest that the log of the square of the fractional rms variability amplitude, rms^2, seems to correlate with the log of the AGN black-hole mass, M_BH, with larger black holes being less variable for a fixed time interval. This has motivated the theoretical...

  9. Characteristics of a 'HARP' signal processor with analog memory operated with segmented silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Anghinolfi, F.; Aspell, P. (CERN, Geneva (Switzerland)); Bonino, R. (Geneva Univ. (Switzerland)) (and others)

    1994-08-01

    For future particle experiments, the detector systems will have a large number of detecting elements, and these will provide raw data at [approximately] 50 MHz rates. As an example, the silicon outer tracker (SIT) for the ATLAS detector may consist of 5 planes of silicon strip and pad detectors with 390,000 independent channels per plane. The signal processing electronics must comply with the strong limitation on electrical power and cooling in the central barrel. A 32 channel analog VLSI detector readout chip (HARP32) with an input charge preamplifier, a 64-cell current integrating analog memory in each channel and a common analog multiplexer, has been used in a test beam with segmented silicon detectors. The device was operated at the LHC clock speed of 66 MHz. The different pedestal variations seen at the output are analyzed: the input noise [sigma][sub n] amounts to 2.8mV r.m.s., the pedestal non-uniformity in channel [sigma][sub ped] to 1.2mV r.m.s., the channel to channel pedestal variation [sigma][sub ch] to 4.0mV r.m.s., and an output baseline shift [sigma][sub obs] of 3.5mV r.m.s. has been observed.

  10. Improvements on Signal Processing for HF Radar

    Institute of Scientific and Technical Information of China (English)

    LIU Yongtan; SHEN Yiying

    2001-01-01

    In this paper improvements on signalprocessing are achieved to enhance the performancesof H-F radar system, being unobtainable by the con-ventional signal processing. Using the improved sig-nal processing both high range resolution and longcoherent integration time may be obtained for goodbenefit to the target resolution and weak signal de-tection. Modification to the unmatched correspon-dence between range delay samples and range resolu-tion ceils saves an additional accumulation loss in therange processing. Finally, comparisons between theimproved and the conventional signal processing aregiven by numerical simulation.

  11. Simultaneous ground- and satellite-based observation of MF/HF auroral radio emissions

    Science.gov (United States)

    Sato, Yuka; Kumamoto, Atsushi; Katoh, Yuto; Shinbori, Atsuki; Kadokura, Akira; Ogawa, Yasunobu

    2016-05-01

    We report on the first simultaneous measurements of medium-high frequency (MF/HF) auroral radio emissions (above 1 MHz) by ground- and satellite-based instruments. Observational data were obtained by the ground-based passive receivers in Iceland and Svalbard, and by the Plasma Waves and Sounder experiment (PWS) mounted on the Akebono satellite. We observed two simultaneous appearance events, during which the frequencies of the auroral roar and MF bursts detected at ground level were different from those of the terrestrial hectometric radiation (THR) observed by the Akebono satellite passing over the ground-based stations. This frequency difference confirms that auroral roar and THR are generated at different altitudes across the F peak. We did not observe any simultaneous observations that indicated an identical generation region of auroral roar and THR. In most cases, MF/HF auroral radio emissions were observed only by the ground-based detector, or by the satellite-based detector, even when the satellite was passing directly over the ground-based stations. A higher detection rate was observed from space than from ground level. This can primarily be explained in terms of the idea that the Akebono satellite can detect THR emissions coming from a wider region, and because a considerable portion of auroral radio emissions generated in the bottomside F region are masked by ionospheric absorption and screening in the D/E regions associated with ionization which results from auroral electrons and solar UV radiation.

  12. Forward physics in CMS: Simulation of PMT hits in HF and Higgs mass reconstruction methods with a focus on forward jet tagging

    CERN Document Server

    Moeller, Anthony Richard

    2014-01-01

    Abnormally high energy events were seen in the Hadronic Forward (HF) calorimeter for pion and muon data during testbeam in 2004. Analysis of testbeam data suggested that such events were caused by particles traveling the entire length of HF and striking the photomultiplier (PMT) windows in the readout box behind HF. Charged particles traversing the window of the PMT emit cerenkov radiation, which creates abnormally high energy events in the data. To further study these events, a modification of the existing official CMS HF simulation was created that added the PMT windows to the simulation as sensitive detectors. In agreement with testbeam data, abnormally high energy events in the PMTs were seen in the simulation for muons and pions. The simulation was then extended to jets simulated with Pythia, and then for collision like events as well. PMT hits were seen in both of these cases. Energy sharing between PMTs for long and short fibers in HF as well as timing differences between normal HF events and PMT event...

  13. Systematic Study on Triaxial Superdeformed Bands of Hf Isotopes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Da-Li; DING Bin-Gang

    2009-01-01

    Properties of the triaxial superdeformed (TSD) bands of Hf isotopes are investigated systematically within the supersymmetry scheme including many-body interactions and a perturbation possessing the SO(5) (or SU(5)) symmetry on the rotational symmetry. Quantitatively good results of the γ-ray energies, the dynamical moments of inertia,and the spin of the TSD bands in Hf isotopes are obtained. It shows that this approach is quite powerful in describing the properties of the triaxial superdeformation in Hf isotopes.

  14. Determining Energy Distributions of HF-Accelerated Electrons at HAARP

    Science.gov (United States)

    2015-11-18

    AFRL-AFOSR-VA-TR-2015-0383 Determining energy distributions of HF-accelerated electrons at HAARP Christopher Fallen University of Alaska Fairbanks...2012 - 11/14/2015 4. TITLE AND SUBTITLE Determining energy distributions of HF-accelerated electrons at HAARP 5a. CONTRACT NUMBER FA9550-12-1-0424...transmitted from the High-frequency Active Auroral Research Program ( HAARP ) transmitter in Alaska. For a given fixed HF-plasma interaction altitude

  15. Physics of the Geospace Response to Powerful HF Radio Waves

    Science.gov (United States)

    2012-10-31

    studies of the response of the Earth’s space plasma to high-power HF radio waves from the High-frequency Active Auroral Research Program ( HAARP ...of HF heating and explored to simulate artificial ducts. DMSP- HAARP experiments revealed that HF-created ion outflows and artificial density ducts...in the topside ionosphere appeared faster than predicted by the models, pointing to kinetic (suprathermal) effects. CHAMP/GRACE- HAARP experiments

  16. Analysis of transverse RMS emittance growth of a beam induced by spherical and chromatic aberration in a solenoidal field

    Energy Technology Data Exchange (ETDEWEB)

    Dash, Radhakanta, E-mail: radhakanta.physics@gmail.com [Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India); Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Nayak, Biswaranjan [Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India); Sharma, Archana; Mittal, Kailash C. [Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India); Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2016-01-21

    In a medium energy beam transport line transverse rms emittance growth associated with spherical aberration is analysed. An analytical expression is derived for beam optics in a solenoid field considering terms up to the third order in the radial displacement. Two important phenomena: effect of spherical aberrations in axial-symmetric focusing lens and influence of nonlinear space charge forces on beam emittance growth are discussed for different beam distributions. In the second part nonlinear effect associated with chromatic aberration that describes the growth of emittance and distortion of phase space area is discussed.

  17. Analysis of transverse RMS emittance growth of a beam induced by spherical and chromatic aberration in a solenoidal field

    Science.gov (United States)

    Dash, Radhakanta; Nayak, Biswaranjan; Sharma, Archana; Mittal, Kailash C.

    2016-01-01

    In a medium energy beam transport line transverse rms emittance growth associated with spherical aberration is analysed. An analytical expression is derived for beam optics in a solenoid field considering terms up to the third order in the radial displacement. Two important phenomena: effect of spherical aberrations in axial-symmetric focusing lens and influence of nonlinear space charge forces on beam emittance growth are discussed for different beam distributions. In the second part nonlinear effect associated with chromatic aberration that describes the growth of emittance and distortion of phase space area is discussed.

  18. Determining phase-space properties of the IHEP RFQ output beam using the RMS beam widths from wire-scanners

    CERN Document Server

    Peng, Jun; Liu, Hua-Chang; Jiang, Hong-Ping; Li, Peng; Li, Fang; Li, Jian; Liu, Mei-Fei; Mu, Zhen-Cheng; Meng, Cai; Meng, Ming; Ouyang, Hua-Fu; Rong, Lin-Yan; Tian, Jian-Min; Wang, Biao; Wang, Bo; Xu, Tao-Guang; Xu, Xin-An; Yao, Yuan; Xin, Wen-Qu; Zhao, Fu-Xiang; Zeng, Lei; Zhou, Wen-Zhong

    2015-01-01

    A beam line is built after the IHEP RFQ for halo study. To determine transverse emittance and ellipse parameters of the RFQ output beam, beam size data obtained from the first two of 14 wire scanners are employed. By using the transfer matrix method and the least square method, a set of linear equations were set up and solved. The solutions were then applied as initial beam parameters in multi-particle simulations to check the method of calculation. It is shown that difference between the simulated RMS beam size and the measured one at the measurement location is less than 7%, which is acceptable in our experiments.

  19. Predictions for fatigue crack growth life of cracked pipes and pipe welds using RMS SIF approach and experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Arora, Punit, E-mail: punit@barc.gov.in [Bhabha Atomic Research Centre, Department of Atomic Energy, Maharashtra, Mumbai 400 085 (India); Singh, P.K.; Bhasin, Vivek; Vaze, K.K.; Ghosh, A.K. [Bhabha Atomic Research Centre, Department of Atomic Energy, Maharashtra, Mumbai 400 085 (India); Pukazhendhi, D.M.; Gandhi, P.; Raghava, G. [Structural Engineering Research Centre, Chennai 600 113 (India)

    2011-10-15

    The objective of the present study is to understand the fatigue crack growth behavior in austenitic stainless steel pipes and pipe welds by carrying out analysis/predictions and experiments. The Paris law has been used for the prediction of fatigue crack growth life. To carry out the analysis, Paris constants have been determined for pipe (base) and pipe weld materials by using Compact Tension (CT) specimens machined from the actual pipe/pipe weld. Analyses have been carried out to predict the fatigue crack growth life of the austenitic stainless steel pipes/pipes welds having part through cracks on the outer surface. In the analyses, Stress Intensity Factors (K) have been evaluated through two different schemes. The first scheme considers the 'K' evaluations at two points of the crack front i.e. maximum crack depth and crack tip at the outer surface. The second scheme accounts for the area averaged root mean square stress intensity factor (K{sub RMS}) at deepest and surface points. Crack growth and the crack shape with loading cycles have been evaluated. In order to validate the analytical procedure/results, experiments have been carried out on full scale pipe and pipe welds with part through circumferential crack. Fatigue crack growth life evaluated using both schemes have been compared with experimental results. Use of stress intensity factor (K{sub RMS}) evaluated using second scheme gives better fatigue crack growth life prediction compared to that of first scheme. Fatigue crack growth in pipe weld (Gas Tungsten Arc Welding) can be predicted well using Paris constants of base material but prediction is non-conservative for pipe weld (Shielded Metal Arc Welding). Further, predictions using fatigue crack growth rate curve of ASME produces conservative results for pipe and GTAW pipe welds and comparable results for SMAW pipe welds. - Highlights: > Predicting fatigue crack growth of Austenitic Stainless Steel pipes and pipe welds. > Use of RMS-SIF and

  20. PEMISAHAN Zr – Hf SECARA SINAMBUNG MENGGUNAKAN MIXER SETTLER

    Directory of Open Access Journals (Sweden)

    Dwi Biyantoro

    2017-01-01

    Full Text Available ABSTRAK PEMISAHAN Zr – Hf SECARA SINAMBUNG MENGGUNAKANMIXER SETTLER. Telah dilakukan pemisahanZr – Hf secara sinambung menggunakan pengaduk pengenap (mixer settler 16 stage. Larutan umpan adalah zirkon nitrat dengan kadar Zr = 30786 ppm dan Hf = 499 ppm. Ekstraktan dipakai adalah solven 60 % TBP dalam kerosen dan larutan scrubbingyang dipakai adalah asam nitrat 1 M. Umpan masuk pada stageke 5 dikontakkan secara berlawanan arah dengan solven masuk pada stage ke 16 dan larutan scrubbing masuk pada stage ke 1. Tujuan penelitian ini adalah memisahkan unsur Zr dan Hf dari hasil olah pasir zirkon menggunakan solven TBP dengan alat mixer settler16 stage. Analisis umpan dan hasil proses pemisahan untuk zirkonium (Zr dilakukan dengan menggunakan alat pendar sinar-X, sedangkananalisis unsur hafnium (Hf menggunakan Analisis Pengaktifan Neutron (APN. Parameter penelitian dilakukan dengan variasi keasaman asam nitrat dalam umpan dan variasi waktu pada berbagai laju pengadukan. Hasil penelitian pemisahan unsur Zr dengan Hf diperolehkondisi optimum pada keasaman umpan 4 N HNO3, keseimbangan dicapai setelah 3jam dan laju pengadukan 3300 rpm. Hasil ekstrak  unsur zirkon (Zr diperoleh kadar sebesar 28577 ppm dengan efisiensi 92,76 % serta kadar pengotor hafnium (Hf sebesar 95 ppm. Kata Kunci: pemisahan Zr, Hf, ekstraksi, mixer settler, alat pendar sinar-X, APN. ABSTRACT SEPARATION of Zr - Hf CONTINUOUSLY USE THE MIXER SETTLER. Separation of Zr - Hf continuously using mixer settler 16 stage has been done. The feed solution is zircon nitrate concentration of Zr = 30786 ppm  and Hf = 499 ppm. As the solvent used extractant 60 % TBP in 40 % kerosene. Nitric acid solution used srubbing 1 M. The feed entered into stage to 5 is contacted with solvents direction on the stage to 16 and the scrubbing solution enter the stage to 1. The purpose of this study is to separate Zr and Hf of the results from the process of zircon sand using solvent TBP using 16 stage

  1. Mitigating Doppler shift effect in HF multitone data modem

    Science.gov (United States)

    Sonlu, Yasar

    1989-09-01

    Digital communications over High Frequency (HF) radio channels are getting important in recent years. Current HF requirements are for data transmission at rates 2.4 kbps or more to accommodate computer data links and digital secure voice. HF modems which were produced to meet these speeds are, serial modems and parallel modems. On the other hand, the HF sky-wave communication medium, the ionosphere, has some propagation problems such as multipath and Doppler shift. The effect of Doppler shift in a parallel modem which employs Differential Quadrature Phase Shift Keying (DQPSK) modulation is considered and a correction method to mitigate the Doppler Shift effect is introduced.

  2. Epitaxial Thin Films of Y doped HfO2

    Science.gov (United States)

    Serrao, Claudy; Khan, Asif; Ramamoorthy, Ramesh; Salahuddin, Sayeef

    Hafnium oxide (HfO2) is one of a few metal oxides that is thermodynamically stable on silicon and silicon oxide. There has been renewed interest in HfO2 due to the recent discovery of ferroelectricity and antiferroelectricity in doped HfO2. Typical ferroelectrics - such as strontium bismuth tantalate (SBT) and lead zirconium titanate (PZT) - contain elements that easily react with silicon and silicon oxide at elevated temperatures; therefore, such ferroelectrics are not suited for device applications. Meanwhile, ferroelectric HfO2 offers promise regarding integration with silicon. The stable phase of HfO2 at room temperature is monoclinic, but HfO2 can be stabilized in the tetragonal, orthorhombic or even cubic phase by suitable doping. We stabilized Y-doped HfO2 thin films using pulsed laser deposition. The strain state can be controlled using various perovskite substrates and controlled growth conditions. We report on Y-doped HfO2 domain structures from piezo-response force microscopy (PFM) and structural parameters via X-ray reciprocal space maps (RSM). We hope this work spurs further interest in strain-tuned ferroelectricity in doped HfO2.

  3. Microstructural characterization of as-cast hf-b alloys

    Directory of Open Access Journals (Sweden)

    João Carlos Jânio Gigolotti

    2012-04-01

    Full Text Available An accurate knowledge of several metal-boron phase diagrams is important to evaluation of higher order systems such as metal-silicon-boron ternaries. The refinement and reassessment of phase diagram data is a continuous work, thus the reevaluation of metal-boron systems provides the possibility to confirm previous data from an investigation using higher purity materials and better analytical techniques. This work presents results of rigorous microstructural characterization of as-cast hafnium-boron alloys which are significant to assess the liquid composition associated to most of the invariant reactions of this system. Alloys were prepared by arc melting high purity hafnium (minimum 99.8% and boron (minimum 99.5% slices under argon atmosphere in water-cooled copper crucible with non consumable tungsten electrode and titanium getter. The phases were identified by scanning electron microscopy, using back-scattered electron image mode and X-ray diffraction. In general, a good agreement was found between our data and those from the currently accepted Hafnium-Boron phase diagram. The phases identified are αHfSS and B-RhomSS, the intermediate compounds HfB and HfB2 and the liquide L. The reactions are the eutectic L ⇔ αHfSS + HfB and L ⇔ HfB2 + B-Rhom, the peritectic L + HfB2 ⇔ HfB and the congruent formation of HfB2.

  4. A DFT study of temperature dependent dissociation mechanism of HF in HF(H2O)7 cluster

    Indian Academy of Sciences (India)

    Swatantra K Yadav; Hirdyesh Mishra; Ashwani K Tiwari

    2015-10-01

    We report a Density Functional Theoretical (DFT) study of dissociation of Hydrogen Fluoride (HF) in HF(H2O)7 cluster, using B3LYP functional and empirical exchange correlation functional M06-2X along with 6-31+G(d,p) basis set. Dissociation constant, KRP, of HF dissociation and pKa values of HF in cluster at various temperatures have been reported. It has been found that both KRP and pKa are highly dependent on temperature. The variation of pKa with temperature suggests that HF is strong acid at lower temperatures. Our study also reveals that HF is a stronger acid in water cluster than in bulk water. Further, the results obtained by DFT calculations have been compared with the earlier reported results obtained from Monte Carlo (MC) simulation. It is found that DFT results are qualitatively consistent with the results of MC simulation but quantitatively different.

  5. Hf-W chronometry of primitive achondrites

    Science.gov (United States)

    Schulz, T.; Münker, C.; Mezger, K.; Palme, H.

    2010-03-01

    Metal segregation and silicate melting on asteroids are the most incisive differentiation events in the early evolution of planetary bodies. The timing of these events can be constrained using the short-lived 182Hf- 182W radionuclide system. Here we present new 182Hf- 182W data for major types of primitive achondrites including acapulcoites, winonaites and one lodranite. These meteorites are of particular interest because they show only limited evidence for partial melting of silicates and are therefore intermediate between chondrites and achondrites. For acapulcoites we derived a 182Hf- 182W age of Δ tCAI = 4.1 +1.2/ -1.1 Ma. A model age for winonaite separates calculated from the intercept of the isochron defines an age of Δ tCAI = 4.8 +3.1/ -2.6 Ma (assuming a bulk Hf/W ratio of ˜1.2). Both ages most likely define primary magmatic events on the respective parent bodies, such as melting of metal, although metal stayed in place and did not segregate to form a core. A later thermal event is responsible for resetting of the winonaite isochron, yielding an age of Δ tCAI = 14.3 +2.7/ -2.2 Ma, significantly younger than the model age. Assuming a co-genetic relationship between winonaites and silicates present in IAB iron meteorites (based on oxygen isotope composition) and including data by Schulz et al. (2009), a common parent body chronology can be established. Magmatic activity occurred between ˜1.5 and 5 Ma after CAIs. More than 5 Ma later, intensive thermal metamorphism has redistributed Hf-W. Average cooling rates calculated for the winonaite/IAB parent asteroid range between ˜35 and ˜4 K/Ma, most likely reflecting different burial depths. Cooling rates obtained for acapulcoites were ˜40 K/Ma to ˜720 K and then ˜3 K/Ma to ˜550 K. Accretion and subsequent magmatism on the acapulcoite parent body occurred slightly later if compared to most achondrite parent bodies (e.g., angrites, ureilites and eucrites), in this case supporting the concept of an inverse

  6. Pressure induced novel compounds in the Hf-O system from first-principles calculations

    OpenAIRE

    2015-01-01

    Using first-principles evolutionary simulations, we have systematically investigated phase stability in the Hf-O system at pressure up to 120 GPa. New compounds Hf5O2, Hf3O2, HfO and HfO3 are discovered to be thermodynamically stable at certain pressure ranges and a new stable high-pressure phase is found for Hf2O with space group Pnnm and anti-CaCl2-type structure. Both P62m-HfO and P4m2-Hf2O3 show semimetallic character. Pnnm-HfO3 shows interesting structure, simultaneously containing oxide...

  7. Ferroelectricity of nondoped thin HfO2 films in TiN/HfO2/TiN stacks

    Science.gov (United States)

    Nishimura, Tomonori; Xu, Lun; Shibayama, Shigehisa; Yajima, Takeaki; Migita, Shinji; Toriumi, Akira

    2016-08-01

    We report on the impact of TiN interfaces on the ferroelectricity of nondoped HfO2. Ferroelectric properties of nondoped HfO2 in TiN/HfO2/TiN stacks are shown in capacitance-voltage and polarization-voltage characteristics. The Curie temperature is also estimated to be around 500 °C. The ferroelectricity of nondoped HfO2 clearly appears by thinning HfO2 film down to ˜35 nm. We directly revealed in thermal treatments that the ferroelectric HfO2 film on TiN was maintained by covering the top surface of HfO2 with TiN, while it was followed by a phase transition to the paraelectric phase in the case of the open surface of HfO2. Thus, it is concluded that the ferroelectricity in nondoped HfO2 in this study was mainly driven by both of top and bottom TiN interfaces.

  8. On the rms errors and dynamic ranges of triple- and quadruple-pulse particle tracking velocimetry (PTV)

    Science.gov (United States)

    Ding, Liuyang; Adrian, Ronald; Gogineni, Sivaram

    2016-11-01

    Multi-pulse PTV extends conventional dual-pulse PTV by fitting a polynomial to particle locations measured from three or four pulses in a burst, aiming at more accurately resolving a particle short-period trajectory. Particle velocity and acceleration are then evaluated at an optimal time minimizing rms errors. Numerical simulations were performed to completely study the behaviors of position, velocity, and acceleration rms errors of triple- and quadruple-pulse PTV in a 4-D space spanned by four dimensionless variables - normalized time, normalized displacement, normalized particle locating noise, and acceleration factor. We compared three analysis methods - 3-pulse with quadratic fitting, 4-pulse with cubic fitting and 4-pulse with quadratic least-square fitting. In addition, generalized definitions of dynamic spatial range (DSR) and dynamic velocity range (DVR) are proposed for multi-pulse analyses. We calculated DSR ratios and DVR ratios between the multi-pulse and 2-pulse under various flow conditions and noise levels. It is found that the DSR and DVR could be improved by up to 100 times and 10 times, respectively, when the particle trajectory is strongly curved, deceleration is pronounced, and particle locations are accurately determined. This work is supported by ONR N00014-14-C-0095.

  9. Radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Taleyarkhan, Rusi P.

    2017-06-27

    Alpha particle detecting devices are disclosed that have a chamber that can hold a fluid in a tensioned metastable state. The chamber is tuned with a suitable fluid and tension such that alpha emitting materials such as radon and one or more of its decay products can be detected. The devices can be portable and can be placed in areas, such as rooms in dwellings or laboratories and used to measure radon in these areas, in situ and in real time. The disclosed detectors can detect radon at and below 4 pCi/L in air; also, at and below 4,000 pCi/L or 300 pCi/L in water.

  10. A direct electron detector for time-resolved MeV electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vecchione, T.; Denes, P.; Jobe, R. K.; Johnson, I. J.; Joseph, J. M.; Li, R. K.; Perazzo, A.; Shen, X.; Wang, X. J.; Weathersby, S. P.; Yang, J.; Zhang, D.

    2017-03-01

    The introduction of direct electron detectors enabled the structural biology revolution of cryogenic electron microscopy. Direct electron detectors are now expected to have a similarly dramatic impact on time-resolved MeV electron microscopy, particularly by enabling both spatial and temporal jitter correction. Here we report on the commissioning of a direct electron detector for time-resolved MeV electron microscopy. The direct electron detector demonstrated MeV single electron sensitivity and is capable of recording megapixel images at 180 Hz. The detector has a 15-bit dynamic range, better than 30-μmμm spatial resolution and less than 20 analogue-to-digital converter count RMS pixel noise. The unique capabilities of the direct electron detector and the data analysis required to take advantage of these capabilities are presented. The technical challenges associated with generating and processing large amounts of data are also discussed.

  11. How the Type of Cosurfactant Impacts Strongly on the Size and Interfacial Composition in Gemini 12-2-12 RMs Explored by DLS, SLS, and FTIR Techniques.

    Science.gov (United States)

    Cuenca, Victor E; Falcone, R Darío; Silber, Juana J; Correa, N Mariano

    2016-01-28

    The limited amount of information about reverse micelles (RMs) made with gemini surfactants, the effect of the n-alcohols in their interface, and the water-entrapped structure in the polar core motivated us to perform this work. Thus, in the present contribution, we use dynamic light scattering (DLS), static light scattering (SLS), and FT-IR techniques to obtain information on RMs structure created, with the gemini dimethylene-1,2-bis(dodecyldimethylammonium) bromide (G12-2-12) surfactant and compare the results with its monomer: dodecyltrimethylammonium bromide (DTAB). In this way, the size of the aggregates formed in different nonpolar organic solvents, the effect of the chain length of n-alcohols used as cosurfactants, and the water-entrapped structure were explored. The data show that the structure of the cosurfactant needed to stabilize the RMs plays a fundamental role, affecting the size and behavior of the aggregates. In contrast to what happens with the RMs formed with the monomer DTAB, water entrapped inside G12-2-12 RMs displays different interaction with the interface depending on the hydrocarbon chain length of the n-alcohol used as cosurfactant. Thus, n-pentanol and n-octanol molecules are located in different regions in the RMs interfaces formed with the gemini surfactant. n-Octanol locates at the RMs interface among the surfactant hydrocarbon tails increasing the water-surfactant polar headgroup interaction. On the other hand, n-pentanol locates at the RMs interface near the polar core, limiting the interaction of water with the micellar inner interface and favoring the water-water interaction in the polar core.

  12. CLIC Detector Power Requirements

    CERN Document Server

    Gaddi, A

    2013-01-01

    An estimate for the CLIC detector power requirements is outlined starting from the available data on power consumptions of the four LHC experiments and considering the differences between a typical LHC Detector (CMS) and the CLIC baseline detector concept. In particular the impact of the power pulsing scheme for the CLIC Detector electronics on the overall detector consumption is considered. The document will be updated with the requirements of the sub-detector electronics once they are more defined.

  13. Pixel Vertex Detectors

    OpenAIRE

    Wermes, Norbert

    2006-01-01

    Pixel vertex detectors are THE instrument of choice for the tracking of charged particles close to the interaction point at the LHC. Hybrid pixel detectors, in which sensor and read-out IC are separate entities, constitute the present state of the art in detector technology. Three of the LHC detectors use vertex detectors based on this technology. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as ...

  14. Synthesis of Freestanding HfO2 Nanostructures

    Science.gov (United States)

    2011-04-05

    Tang J, Fabbri J, Robinson RD, Zhu Y, Herman IP, Steigerwald ML, Brus LE: Solid-solution nanoparticles:use of a nonhydrolytic sol-gel synthesis to...colloidal HfO2 nanorods. Adv Mater 2007, 19:2608-2612. Page 21 5. Qiu X, Howe JY, Cardoso MB, Polat O, Heller W: Size control of highly ordered HfO2

  15. Parametric excitation of whistler waves by HF heater

    Science.gov (United States)

    Kuo, S. P.; Lee, M. C.

    1989-01-01

    Possible generation of whistler waves by Tromso HF heater is investigated. It is shown that the HF heater wave can parametrically decay into a whistler wave and a Langmuir wave. Since whistler waves may have a broad range of frequency, the simultaneously excited Langmuir waves can have a much broader frequency bandwidth than those excited by the parametric decay instability.

  16. Study of {sup 179}Hf{sup m2} excitation

    Energy Technology Data Exchange (ETDEWEB)

    Vishnevsky, I. N.; Zheltonozhsky, V. A., E-mail: zhelton@kinr.kiev.ua; Savrasov, A. N. [National Academy of Sciences of Ukraine, Institute for Nuclear Research (Ukraine); Mazur, V. M. [National Academy of Sciences of Ukraine, Institute of Electronic Physics (Ukraine)

    2016-12-15

    Isomeric ratios of {sup 179}Hf{sup m2,g} yields in the (γ, n) reaction and the cross section for the {sup 179}Hf{sup m2} population in the (α, p) reaction are measured for the first time at the end-point energies of 15.1 and 17.5 MeV for bremsstrahlung photons and 26 MeV for alpha particles. The results are σ = (1.1 ± 0.11) × 10{sup −27} cm{sup 2} for the {sup 176}Lu(α, p){sup 179}Hf{sup m2} reaction and Y{sub m2}/Y{sub g} = (6.1 ± 0.3) × 10{sup −6} and (3.7 ± 0.2) × 10{sup −6} for the {sup 180}Hf(γ, n){sup 179}Hf{sup m22} reaction at E{sub ep} =15.1 and 17.5 MeV, respectively. The experimental data on the relative {sup 179}Hf{sup m2} yield indicate a single-humped shape of the excitation function for the {sup 180}Hf(γ, n){sup 179}Hf{sup m2} reaction. Simulation is performed using the TALYS-1.4 and EMPIRE-3.2 codes.

  17. Diffusion of Hf and Nb in Zr-19%Nb

    Energy Technology Data Exchange (ETDEWEB)

    Zou, H. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Hood, G.M. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Schultz, R.J. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Matsuura, N. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Roy, J.A. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Jackman, J.A. [CANMET, Ottawa, Ont. (Canada). Met. Sci. and Technol.

    1996-05-01

    Diffusion of Hf and Nb in large-grained bcc Zr-19%Nb has been studied. Diffusion coefficients of Hf, D(Hf), were measured in the range 620-1173 K and D(Nb) was measured at 920 and 1167 K. The Hf diffusion profiles were determined by SIMS and the Nb profiles by microtome sectioning and radio-tracer counting. The Hf data show a smooth, temperature-dependent behaviour through the monotectoid temperature, 875 K, and may be characterised by D{approx}10{sup -9}.exp-1.4 (eV/kT) m{sup 2}/s. D(Nb) tends to be lower than the corresponding values for D(Hf). Overall, diffusion of Hf and Nb are characteristic of diffusion in bcc Zr. Surface hold-up (oxide film) at low temperatures was overcome by using ion-implanted Hf diffusion sources. The results are compared with earlier work and discussed in terms of diffusion mechanisms and the {beta}-phase transformation of commercial Zr-2.5Nb. (orig.).

  18. Mechanical design and development of TES bolometer detector arrays for the Advanced ACTPol experiment

    CERN Document Server

    Ward, Jonathan T; Beall, James A; Choi, Steve K; Crowley, Kevin T; Devlin, Mark J; Duff, Shannon M; Gallardo, Patricio M; Henderson, Shawn W; Ho, Shuay-Pwu Patty; Hilton, Gene; Hubmayr, Johannes; Khavari, Niloufar; Klein, Jeffrey; Koopman, Brian J; Li, Dale; McMahon, Jeffrey; Mumby, Grace; Nati, Federico; Niemack, Michael D; Page, Lyman A; Salatino, Maria; Schillaci, Alessandro; Schmitt, Benjamin L; Simon, Sara M; Staggs, Suzanne T; Thornton, Robert; Ullom, Joel N; Vavagiakis, Eve M; Wollack, Edward J

    2016-01-01

    The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling ~5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline profile leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at t...

  19. Characterization of the KID-Based Light Detectors of CALDER

    Science.gov (United States)

    Casali, N.; Bellini, F.; Cardani, L.; Castellano, M. G.; Colantoni, I.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D'Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

    2016-07-01

    The aim of the Cryogenic wide-Area Light Detectors with Excellent Resolution (CALDER) project is the development of light detectors with active area of 5 × 5 cm2 and noise energy resolution smaller than 20 eV RMS, implementing phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the characterization of the first light detectors developed by CALDER. We describe the analysis tools to evaluate the resonator parameters (resonant frequency and quality factors) taking into account simultaneously all the resonance distortions introduced by the read-out chain (as the feed-line impedance and its mismatch) and by the power stored in the resonator itself. We detail the method for the selection of the optimal point for the detector operation (maximizing the signal-to-noise ratio). Finally, we present the response of the detector to optical pulses in the energy range of 0{-}30 keV.

  20. Oxygen Recovery in Hf Oxide Films Fabricated by Sputtering

    Institute of Scientific and Technical Information of China (English)

    JIANG Ran; LI Zi-Feng

    2009-01-01

    The chemical structure of ultrathin Hf oxide films (< 10 nm) fabricated by a standard sputtering method is investigated using x-ray spectroscopy and Rutherford backscattering spectroscopy. According to the experiments,oxygen species are impacted to the HfO2/Si interface during the initial sputtering, and then released back to the upper Hf02 region driven by the oxygen concentration grads. A vacuum annealing can greatly enhance this recovery process. Additionally, significant SiO2 reduction in the interface is observed after the vacuum annealing for the thick HfO2 films in our experiment. It might be an effective method to confine the interracial layer thickness by sputtering thick HfO2 in no-oxygen ambient.

  1. Crystal structure of Si-doped HfO2

    Science.gov (United States)

    Zhao, Lili; Nelson, Matthew; Aldridge, Henry; Iamsasri, Thanakorn; Fancher, Chris M.; Forrester, Jennifer S.; Nishida, Toshikazu; Moghaddam, Saeed; Jones, Jacob L.

    2014-01-01

    Si-doped HfO2 was prepared by solid state synthesis of the starting oxides. Using Rietveld refinement of high resolution X-ray diffraction patterns, a substitutional limit of Si in HfO2 was determined as less than 9 at. %. A second phase was identified as Cristobalite (SiO2) rather than HfSiO4, the latter of which would be expected from existing SiO2-HfO2 phase diagrams. Crystallographic refinement with increased Si-dopant concentration in monoclinic HfO2 shows that c/b increases, while β decreases. The spontaneous strain, which characterizes the ferroelastic distortion of the unit cell, was calculated and shown to decrease with increasing Si substitution.

  2. The (178m2)Hf Controversy

    Energy Technology Data Exchange (ETDEWEB)

    Becker, J A; Gemmell, D S; Schiffer, J P; Wilhelmy, J B

    2003-07-24

    Since its discovery in the 1960's the {sup 178m2}Hf isomer has garnered high attention from both the basic and applied communities in nuclear science. It's combination of high spin (16+), long half life (31 yrs), and high excitation energy (2.446 MeV) offer unique possibilities as an energy storage medium. Interest in the isomer was rekindled beginning in 1999 when a series of publications began to appear from a group (referred to here as the ''Texas collaboration'') primarily based at the University of Texas, Dallas [1]. They reported observations that some of the stored energy could be released (''triggered'') when the isomer was exposed to a fluence of photons in the energy range {approx}10 to {approx}60 keV. The implications of this observation are profound. Even though the claimed cross section for the process was {approx}7 orders of magnitude greater than would be predicted from the known systematics of photon absorption by nuclei in this mass range [2], such a highly efficient method for triggering the isomeric deexcitation immediately suggested applications utilizing the explosive or the controlled gradual energy release from a very compact source. The prospect of such applications has focused considerable interest on realizing the promise that is implicit in the reported observations. However, two experiments performed by a group from ANL/LANL/LLNL at the Advanced Photon Source at Argonne (the ''APS collaboration'') reported negative results for the observation of any photon-triggered deexcitation of the {sup 178m2}Hf isomer [3]. This has led to a continued controversy, where both sides have adamantly defended their observations. At this point an outsider has difficulty determining whether there is indeed a triggering effect that should be pursued energetically with substantial resources, or whether the phenomenon consists of overly optimistic interpretation of data.

  3. Solution processable organic/inorganic hybrid ultraviolet photovoltaic detector

    Directory of Open Access Journals (Sweden)

    Xiaopeng Guo

    2016-05-01

    Full Text Available Ultraviolet (UV photodetector is a kind of important optoelectronic device which can be widely used in scientific and engineering fields including astronomical research, environmental monitoring, forest-fire prevention, medical analysis, and missile approach warning etc. The development of UV detector is hindered by the acquirement of stable p-type materials, which makes it difficult to realize large array, low-power consumption UV focal plane array (FPA detector. Here, we provide a novel structure (Al/Poly(9,9-di-n-octylfuorenyl-2,7-diyl(PFO/ZnO/ITO to demonstrate the UV photovoltaic (PV response. A rather smooth surface (RMS roughness: 0.28 nm may be reached by solution process, which sheds light on the development of large-array, light-weight and low-cost UV FPA detectors.

  4. MUON DETECTOR

    CERN Multimedia

    F. Gasparini

    DT As announced in the previous Bulletin MU DT completed the installation of the vertical chambers of barrel wheels 0, +1 and +2. 242 DT and RPC stations are now installed in the negative barrel wheels. The missing 8 (4 in YB-1 and 4 in YB-2) chambers can be installed only after the lowering of the two wheels into the UX cavern, which is planned for the last quarter of the year. Cabling on the surface of the negative wheels was finished in May after some difficulties with RPC cables. The next step was to begin the final commissioning of the wheels with the final trigger and readout electronics. Priority was giv¬en to YB0 in order to check everything before the chambers were covered by cables and services of the inner detectors. Commissioning is not easy since it requires both activity on the central and positive wheels underground, as well as on the negative wheels still on the surface. The DT community is requested to commission the negative wheels on surface to cope with a possible lack of time a...

  5. Integrated design of RMS based on coupling modeling and knowledge flow%基于耦合建模与知识流的RMS一体化设计

    Institute of Scientific and Technical Information of China (English)

    徐永成; 李岳; 陈循

    2013-01-01

    针对国内外研究热点和难点——装备可靠性、维修性、保障性(reliability,maintainability and supportability,RMS)一体化设计,提出其中的瓶颈是RMS之间的强耦合机制及其设计知识流动控制问题.为此,分析、论证并提出了一种装备RMS一体化设计的创新研究方案:首先采用具有严格数学基础的图论方法——分层加权有向图进行RMS建模,以系统、科学、客观地刻画RMS强耦合关系;引入图书情报、管理工程中的知识流理论以实现RMS耦合设计知识的流动控制;采用模糊粗糙集理论以解决RMS不确定知识问题.可为装备RMS一体化设计理论的发展提供一种创新的、可行的参考思路.%The integrated design of reliability,maintainability and supportability (RMS) is one of key technical challenges and research hot spots in the engineering and academic field at home and abroad.Although achievements have been attained in the individual engineering of reliability,maintainability and supportability,the problem of strong-coupling between RMS and control of design knowledge has not been resolved up to now.The strong-coupling between RMS characteristic parameters and their logic relations results in the intersectant design processes and knowledge of RMS,which affects the real integration of RMS data and design tools.In this paper one research solution of RMS integrated design is presented.Firstly,the layered weighted digraphs method is introduced to model and decouple this strong-coupling relationship scientifically and impersonally because the graph theory has the strict foundation of mathematics.Then,the knowledge flow theory of library and management science is introduced to lead the scientific flow of design knowledge between the RMS coupling fields.Finally,the fuzzy rough sets theory is adopted to study the problems of uncertain knowledge and case data missing under coupling RMS case.This research solution can provide one new idea and

  6. STS-46 EURECA-1L held in pre-deployment position by RMS over OV-104's PLB

    Science.gov (United States)

    1992-01-01

    STS-46 European Retrievable Carrier 1L (EURECA-1L) satellite with solar arrays extended, is grappled by the remote manipulator system (RMS) end effector and is positioned above the payload bay (PLB) of Atlantis, Orbiter Vehicle (OV) 104 during pre-deployment activities. In the foreground the IMAX Cargo Bay Camera (ICBC) mounted on Small Payloads Accomodations (SPA) getaway special (GAS) beam interface appears on the starboard wall and the stowed Tethered Satellite System 1 (TSS-1) satellite mounted in the satellite support assembly (SSA) on the unpressurized spacelab (SL) pallet (center). The scene is backdropped by the Earth's limb. A 16mm lens gives this 35mm frame a 'fish-eye' effect.

  7. Ride Performance Analysis of Half-Car Model for Semi-Active System Using RMS as Performance Criteria

    Directory of Open Access Journals (Sweden)

    S.I. Ihsan

    2009-01-01

    Full Text Available The work aims to study the root mean square (RMS responses to acceleration input for four state variables: the ms vertical acceleration, the ms pitch angular acceleration and the front and rear deflections of the suspensions. A half-car two degree-of-freedom model of semi-active control scheme is analyzed and compared with the conventional passive suspension system. Frequency response of the transfer function for the heave, pitch of the sprung mass and suspension deflections are initially compared and then mean square analysis is utilized to see the effect of semi-active scheme. Results indicate that significant improvements were achieved in the sprung mass heave and pitch responses using semi-active control scheme. However results for the rear and front suspension deflection show that there are limiting values of damping coefficient beyond which, the semi-active scheme becomes disadvantageous than the passive system.

  8. Ferroelectricity-modulated resistive switching in Pt/Si:HfO2/HfO2-x /Pt memory

    Science.gov (United States)

    Ran, Jiang; Xianghao, Du; Zuyin, Han

    2016-08-01

    It is investigated for the effect of a ferroelectric Si:HfO2 thin film on the resistive switching in a stacked Pt/Si:HfO2/highly-oxygen-deficient HfO2-x /Pt structure. Improved resistance performance was observed. It was concluded that the observed resistive switching behavior was related to the modulation of the width and height of a depletion barrier in the HfO2-x layer, which was caused by the Si:HfO2 ferroelectric polarization field effect. Reliable switching reproducibility and long data retention were observed in these memory cells, suggesting their great potential in non-volatile memories applications with full compatibility and simplicity. Project supported by the National Natural Science Foundation of China (No. 11374182), the Natural Science Foundation of Shandong Province (No. ZR2012FQ012), and the Jinan Independent Innovation Projects of Universities (No. 201303019).

  9. Power-Stepped HF Cross Modulation Experiments at HAARP

    Science.gov (United States)

    Greene, S.; Moore, R. C.; Langston, J. S.

    2013-12-01

    High frequency (HF) cross modulation experiments are a well established means for probing the HF-modified characteristics of the D-region ionosphere. In this paper, we apply experimental observations of HF cross-modulation to the related problem of ELF/VLF wave generation. HF cross-modulation measurements are used to evaluate the efficiency of ionospheric conductivity modulation during power-stepped modulated HF heating experiments. The results are compared to previously published dependencies of ELF/VLF wave amplitude on HF peak power. The experiments were performed during the March 2013 campaign at the High Frequency Active Auroral Research Program (HAARP) Observatory. HAARP was operated in a dual-beam transmission format: the first beam heated the ionosphere using sinusoidal amplitude modulation while the second beam broadcast a series of low-power probe pulses. The peak power of the modulating beam was incremented in 1-dB steps. We compare the minimum and maximum cross-modulation effect and the amplitude of the resulting cross-modulation waveform to the expected power-law dependence of ELF/VLF wave amplitude on HF power.

  10. HF dissociation in water clusters by computer simulations

    OpenAIRE

    Elena, Alin Marin

    2013-01-01

    We perform Restrained hybrid Monte Carlo simulations to compute the equilibrium constant of the dissociation reaction of HF in HF(H2O)7. We find that, like in the bulk, hydrofluoric acid, is a weak acid also in the cubic HF(H2O)7 cluster, and that its acidity is higher at lower T. This latter phenomenon has a (vibrational) entropic origin, namely it is due to the reduction of the (negative) T∆S contribution to the variation of free energy between the reactant and product. We found also ...

  11. The first section of the CMS detector (centre of photo) arriving from the vertical shaft, viewed from the cavern floor.

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    In the early morning of 2 November, the first section of the CMS detector began its eagerly awaited descent into the underground cavern. You may imagine the CMS detector as a loaf of sliced bread, cut into 15 slices of different sizes. The two HF sections are the end pieces; the slices in between will be lowered sequentially according to their positions in the ‘loaf', starting from the HF+ section at the far end of the cavern, towards the access shaft at the opposite end.

  12. Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The rms-flux relations for some observations of GRS 1915+105 are studied.The rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided Zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion disk.The rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion disk.The complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these states.The underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.

  13. Performance of liquid argon neutrino detectors with enhanced sensitivity to scintillation light

    CERN Document Server

    Sorel, M

    2014-01-01

    Scintillation light is used in liquid argon neutrino detectors to provide a trigger signal, veto information against cosmic rays, and absolute event timing. In this work, we discuss additional opportunities offered by detectors with enhanced sensitivity to scintillation light, that is with light collection efficiencies of about $10^{-3}$. We focus on two key detector performance indicators for neutrino oscillation physics: calorimetric neutrino energy reconstruction and neutrino/antineutrino separation in a non-magnetized detector. Our simulations indicate that a neutrino energy resolution as good as 3.3\\% RMS for 4 GeV electron neutrino charged-current interactions can in principle be obtained in a large detector of this type, by using both charge and light information. By exploiting muon capture in argon and scintillation light information to veto muon decay electrons, we also obtain muon neutrino identification efficiencies of about 50\\%, and muon antineutrino misidentification rates at the few percent lev...

  14. Remote Minehunting System (RMS)

    Science.gov (United States)

    2015-12-01

    and electro-optical identification sensor) in a compact, lightweight, and hydrodynamically stable towed body . The AN/AQS-20 localizes mine-like...objects and provides the operator with a visual image and a contact data list. All mission data is recorded by the Littoral Combat Ship (LCS) for post...TECHEVAL -OPEVAL -Full Rate Production - Exercise FRP Contract Options under LRIP Contract (Ch-2) The current estimate for IOC has changed from February

  15. Ionospheric heating with oblique HF waves

    Science.gov (United States)

    Field, Edward C., Jr.; Bloom, Ron M.

    1990-10-01

    Calculations of ionospheric electron density perturbations and ground-level signal changes produce by intense oblique high frequency (HF) transmitters are presented. This analysis considers radio field focusing at caustics, the consequent joule-heating of the surrounding plasma, heat conduction, diffusion, and recombination processes: these being the effects of a powerful oblique 'modifying' wave. It neglects whatever plasma instabilities might occur. Then effects on a secondary 'test' wave that is propagated along the same path as the first are investigated. Calculations predict ground-level field-strength reductions of several dB in the test wave for modifying waves having ERP in the 85 to 90 dBW range. These field-strength changes are similar in sign, magnitude, and location to ones measured in Soviet experiments. The results are sensitive to the model ionosphere assumed, so future experiments should employ the widest possible range of frequencies and propagation conditions. An effective power of 90 dBW seems to be a sort of threshold that, if exceeded, results in substantial rather than small signal changes. The conclusions are based solely on joule-heating and subsequent defocusing of waves passing through caustic regions.

  16. Process Simulation Analysis of HF Stripping

    Directory of Open Access Journals (Sweden)

    Thaer A. Abdulla

    2013-05-01

    Full Text Available    HYSYS process simulator is used for the analysis of existing HF stripping column in LAB plant (Arab Detergent Company, Baiji-Iraq. Simulated column performance and profiles curves are constructed. The variables considered are the thermodynamic model option, bottom temperature, feed temperature, and column profiles for the temperature, vapor flow rate, liquid flow rate and composition. The five thermodynamic models options used (Margules, UNIQUAC, van laar, Antoine, and Zudkevitch-Joffee, affecting the results within (0.1-58% variation for the most cases.        The simulated results show that about 4% of paraffin (C10 & C11 presents at the top stream, which may cause a problem in the LAB production plant. The major variations were noticed for the total top vapor flow rate with bottom temperature and with feed composition. The column profiles maintain fairly constants from tray 5 to tray 18. The study gives evidence about a successful simulation with HYSYS because the results correspond with the real plant operation data.

  17. The (178m2) Hf Controversy

    CERN Document Server

    Becker, J A; Schiffer, J P; Wilhelmy, J

    2003-01-01

    Since its discovery in the 1960's the sup 1 sup 7 sup 8 sup m sup 2 Hf isomer has garnered high attention from both the basic and applied communities in nuclear science. It's combination of high spin (16+), long half life (31 yrs), and high excitation energy (2.446 MeV) offer unique possibilities as an energy storage medium. Interest in the isomer was rekindled beginning in 1999 when a series of publications began to appear from a group (referred to here as the ''Texas collaboration'') primarily based at the University of Texas, Dallas [1]. They reported observations that some of the stored energy could be released (''triggered'') when the isomer was exposed to a fluence of photons in the energy range approx 10 to approx 60 keV. The implications of this observation are profound. Even though the claimed cross section for the process was approx 7 orders of magnitude greater than would be predicted from the known systematics of photon absorption by nuclei in this mass range [2], such a highly efficient method fo...

  18. Grindability of cast Ti-Hf alloys.

    Science.gov (United States)

    Kikuchi, Masafumi; Takahashi, Masatoshi; Sato, Hideki; Okuno, Osamu; Nunn, Martha E; Okabe, Toru

    2006-04-01

    As part of our systematic studies characterizing the properties of titanium alloys, we investigated the grindability of a series of cast Ti-Hf alloys. Alloy buttons with hafnium concentrations up to 40 mass% were made using an argon-arc melting furnace. Each button was cast into a magnesia-based mold using a dental titanium casting machine; three specimens were made for each metal. Prior to testing, the hardened surface layer was removed. The specimens were ground at five different speeds for 1 min at 0.98 N using a carborundum wheel on an electric dental handpiece. Grindability was evaluated as the volume of metal removed per minute (grinding rate) and the volume ratio of metal removed compared to the wheel material lost (grinding ratio). The data were analyzed using ANOVA. A trend of increasing grindability was found with increasing amounts of hafnium, although there was no statistical difference in the grindability with increasing hafnium contents. We also found that hafnium may be used to harden or strengthen titanium without deteriorating the grindability.

  19. Characterization of the KID-Based Light Detectors of CALDER

    CERN Document Server

    Casali, N; Cardani, L; Castellano, M G; Colantoni, I; Coppolecchia, A; Cosmelli, C; Cruciani, A; D'Addabbo, A; Di Dominio, S; Martinez, M; Tomei, C; Vignati, M

    2015-01-01

    The aim of the Cryogenic wide-Area Light Detectors with Excellent Resolution (CALDER) project is the development of light detectors with active area of $5\\times5$ cm$^2$ and noise energy resolution smaller than 20 eV RMS, implementing phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the characterization of the first light detectors developed by CALDER. We describe the analysis tools to evaluate the resonator parameters (resonant frequency and quality factors) taking into account simultaneously all the resonance distortions introduced by the read-out chain (as the feed-line impedance and its mismatch) and by the power stored in the resonator itself. We detail the method for the selection of the optimal point for the detector operation (maximizing the signal-to-noise ratio...

  20. Semiconductor micropattern pixel detectors a review of the beginnings

    CERN Document Server

    Heijne, Erik H M

    2001-01-01

    The innovation in monolithic and hybrid semiconductor 'micropattern' or 'reactive' pixel detectors for tracking in particle physics was actually to fit logic and pulse processing electronics with µW power on a pixel area of less than 0.04 mm2, retaining the characteristics of a traditional nuclear amplifier chain. The ns timing precision in conjunction with local memory and logic operations allowed event selection at > 10 MHz rates with unambiguous track reconstruction even at particle multiplicities > 10 cm-2. The noise in a channel was ~100 e- r.m.s. and enabled binary operation with random noise 'hits' at a level 30 Mrad, respectively.

  1. Pulse-shape discrimination with Cs2HfCl6 crystal scintillator

    Science.gov (United States)

    Cardenas, C.; Burger, A.; Goodwin, B.; Groza, M.; Laubenstein, M.; Nagorny, S.; Rowe, E.

    2017-10-01

    The results of investigation into cesium hafnium chloride (Cs2HfCl6) scintillating crystals as a promising detector to search for rare nuclear processes occurring in Hf isotopes is reported. The light output, quenching factor, and pulse-shape characteristics have been investigated at room temperature. The scintillation response of the crystal induced by α-particles and γ-quanta were studied to determine possibility of particle discrimination. Using the optimal filter method we obtained clear separation between signals with a factor of merit (FOM) = 9.3. This indicates that we are able to fully separate signals originating from α-particles and γ-quanta. Similar fruitful discrimination power was obtained by applying the mean time method (FOM = 7) and charge integration method (FOM = 7.5). The quenching factor for collimated 4 MeV α-particles is found to be 0.36, showing that α-particles generate more than a third of the light compared to γ-quanta at the same energy.

  2. The magnetic properties of $^{\\rm 177}$Hf and $^{\\rm 180}$Hf in the strong coupling deformed model

    OpenAIRE

    Muto, S.; Stone, N. J.; Bingham, C. R.; STONE, J.R; Walker, P. M.; Audi, G.; Gaulard, C.; Köster, U.(Institut Laue-Langevin (ILL), Grenoble, France); Nikolov, J.; Nishimura,K; Ohtsubo, T.; Podolyak, Z.; Risegari, L.; Simpson, G.S.; Veskovic, M.

    2014-01-01

    This paper reports NMR measurements of the magnetic dipole moments of two high-K isomers, the 37/2$^-$, 51.4 m, 2740 keV state in $^{\\rm 177}$Hf and the 8$^-$, 5.5 h, 1142 keV state in $^{\\rm 180}$Hf by the method of on-line nuclear orientation. Also included are results on the angular distributions of gamma transitions in the decay of the $^{\\rm 177}$Hf isotope. These yield high precision E2/M1 multipole mixing ratios for transitions in bands built on the 23/2$^+$, 1.1 s, isomer at 1315 keV ...

  3. Estimation of detection threshold in multiple ship target situations with HF ground wave radar

    Institute of Scientific and Technical Information of China (English)

    Li Hongbo; Shen Yiying; Liu Yongtan

    2007-01-01

    A credible method of calculating the detection threshold is presented for the multiple target situations,which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave radar. This method defines a whole-peak-outlier elimination (WPOE) criterion, which is based on in-peak-samples correlation of each target echo spectra, to trim off the target signals and abnormal disturbances with great amplitude from the complex spectra. Therefore, cleaned background noise samples are obtained to improve the accuracy and reliability of noise level estimation. When the background noise is nonhomogeneous, the detection samples are limited and often occupied heavily with outliers. In this case, the problem that the detection threshold is overvalued can be solved. In applications on experimental data, it is verified that this method can reduce the miss alarm rate of signal detection effectively in multiple target situations as well as make the adaptability of the detector better.

  4. A thirty second isomer in {sup 171}Hf

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, P.; Billowes, J.; Cooper, T.G.; Grant, I.S.; Pearson, M.R.; Wheeler, P.D. [Schuster Laboratory, University of Manchester, M13 9PL (United Kingdom); Cochrane, E.C.A.; Cooke, J.L.; Evans, D.E.; Griffith, J.A.R.; Persson, J.R.; Richardson, D.S.; Tungate, G.; Zybert, L. [School of Physics and Space Research, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Dendooven, P.; Honkanen, A.; Huhta, M.; Oinonen, M.; Penttilae, H.; Aeystoe, J. [Accelerator Laboratory, University of Jyvaeskylae, PL 35 Jyvaeskylae SF-403 51 (Finland)

    1997-09-01

    An isomer has been detected in {sup 171}Hf with a half-life of T{sub 1/2} 29.5(9) s. The state was populated in the {sup 170}Yb({alpha},3n){sup 171m}Hf reaction at a beam energy of E{sub {alpha}} = 50 MeV in an on-line ion guide isotope separator. The isomeric {sup 171m}Hf{sup +} beam was extracted from the ion guide, mass-analysed and implanted in the surface of a microchannel-plate. The half-life of the collected activity was measured from the decay of the microchannel-plate count rate. We associate the isomer with the first excited state in {sup 171}Hf with spin 1/2{sup -} at an excitation energy of 22(2) keV. (author)

  5. HF fiber stuffing in building 186 at CERN

    CERN Multimedia

    Tiziano Camporesi

    2003-01-01

    Each of the 36 HF wedges comprise ca 12000 quartz fibers which are the active element of the calorimeter. The fibers are produced by Polymicro (USA), cleaved and bundled at KFKI, Budapest, Hungary and inserted at CERN.

  6. Low-Frequency Waves in HF Heating of the Ionosphere

    Science.gov (United States)

    Sharma, A. S.; Eliasson, B.; Milikh, G. M.; Najmi, A.; Papadopoulos, K.; Shao, X.; Vartanyan, A.

    2016-02-01

    Ionospheric heating experiments have enabled an exploration of the ionosphere as a large-scale natural laboratory for the study of many plasma processes. These experiments inject high-frequency (HF) radio waves using high-power transmitters and an array of ground- and space-based diagnostics. This chapter discusses the excitation and propagation of low-frequency waves in HF heating of the ionosphere. The theoretical aspects and the associated models and simulations, and the results from experiments, mostly from the HAARP facility, are presented together to provide a comprehensive interpretation of the relevant plasma processes. The chapter presents the plasma model of the ionosphere for describing the physical processes during HF heating, the numerical code, and the simulations of the excitation of low-frequency waves by HF heating. It then gives the simulations of the high-latitude ionosphere and mid-latitude ionosphere. The chapter also briefly discusses the role of kinetic processes associated with wave generation.

  7. Near-infrared LIF spectroscopy of HfF

    CERN Document Server

    Grau, Matt; Loh, Huanqian; Sinclair, Laura C; Stutz, Russel P; Yahn, Tylser S; Cornell, Eric A

    2012-01-01

    The molecular ion HfF$^+$ is the chosen species for a JILA experiment to measure the electron electric dipole moment (eEDM). Detailed knowledge of the spectrum of HfF is crucial to prepare HfF$^+$ in a state suitable for performing an eEDM measurement\\cite{Leanhardt}. We investigated the near-infrared electronic spectrum of HfF using laser-induced fluorescence (LIF) of a supersonic molecular beam. We discovered eight unreported bands, and assign each of them unambiguously, four to vibrational bands belonging to the transition $[13.8]0.5 \\leftarrow X1.5$, and four to vibrational bands belonging to the transition $[14.2]1.5 \\leftarrow X1.5$. Additionally, we report an improved measurement of vibrational spacing of the ground state, as well as anharmonicity $\\omega_e x_e$.

  8. Theoretical Assessment of 178m2Hf De-Excitation

    Energy Technology Data Exchange (ETDEWEB)

    Hartouni, E P; Chen, M; Descalle, M A; Escher, J E; Loshak, A; Navratil, P; Ormand, W E; Pruet, J; Thompson, I J; Wang, T F

    2008-10-06

    This document contains a comprehensive literature review in support of the theoretical assessment of the {sup 178m2}Hf de-excitation, as well as a rigorous description of controlled energy release from an isomeric nuclear state.

  9. Integrated magnetics design for HF-link power converters

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper deals with the design of integrated magnetics for HF-link converters, where the integrated magnetic components do not necessarily belong to the same voltage loop. Depending on the specific HF-link converter topology, the proposed integrated magnetics can either alleviate the derivation...... of independent auxiliary supply voltages from the main transformer or integrate other magnetic structures, thus saving board space and cutting costs....

  10. Integrated magnetics design for HF-link power converters

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.; Andersen, Michael A.E.

    2005-07-01

    This paper deals with the design of integrated magnetics for HF-link converters, where the two integrated magnetic components on the same core do not necessarily belong to the same voltage loop. Depending on the specific HF-link converter topology, the proposed integrated magnetics can either alleviate the derivation of independent auxiliary supply voltages from the main transformer or integrate other magnetic structures, thus saving board space and cutting costs. (au)

  11. Synthesis of freestanding HfO2 nanostructures

    Directory of Open Access Journals (Sweden)

    Boyle Kayla

    2011-01-01

    Full Text Available Abstract Two new methods for synthesizing nanostructured HfO2 have been developed. The first method entails exposing HfTe2 powders to air. This simple process resulted in the formation of nanometer scale crystallites of HfO2. The second method involved a two-step heating process by which macroscopic, freestanding nanosheets of HfO2 were formed as a byproduct during the synthesis of HfTe2. These highly two-dimensional sheets had side lengths measuring up to several millimeters and were stable enough to be manipulated with tweezers and other instruments. The thickness of the sheets ranged from a few to a few hundred nanometers. The thinnest sheets appeared transparent when viewed in a scanning electron microscope. It was found that the presence of Mn enhanced the formation of HfO2 by exposure to ambient conditions and was necessary for the formation of the large scale nanosheets. These results present new routes to create freestanding nanostructured hafnium dioxide. PACS: 81.07.-b, 61.46.Hk, 68.37.Hk.

  12. The isobutylene-isobutane alkylation process in liquid HF revisited.

    Science.gov (United States)

    Esteves, P M; Araújo, C L; Horta, B A C; Alvarez, L J; Zicovich-Wilson, C M; Ramírez-Solís, A

    2005-07-07

    Details on the mechanism of HF catalyzed isobutylene-isobutane alkylation were investigated. On the basis of available experimental data and high-level quantum chemical calculations, a detailed reaction mechanism is proposed taking into account solvation effects of the medium. On the basis of our computational results, we explain why the density of the liquid media and stirring rates are the most important parameters to achieve maximum yield of alkylate, in agreement with experimental findings. The ab initio Car-Parrinello molecular dynamics calculations show that isobutylene is irreversibly protonated in the liquid HF medium at higher densities, leading to the ion pair formation, which is shown to be a minimum on the potential energy surface after optimization using periodic boundary conditions. The HF medium solvates preferentially the fluoride anion, which is found as solvated [FHF](-) or solvated F(-.)(HF)(3). On the other hand, the tert-butyl cation is weakly solvated, where the closest HF molecules appear at a distance of about 2.9 Angstrom with the fluorine termination of an HF chain.

  13. The MINOS Detectors

    CERN Document Server

    Grashorn, A H E W

    2005-01-01

    The Main Injector Neutrino Oscillation Search (MINOS) experiment's primary goal is the precision measurement of the neutrino oscillation parameters in the atmospheric neutrino sector. This long-baseline experiment uses Fermilab's NuMI beam, measured with a Near Detector at Fermilab, and again 735 km later using a Far Detector in the Soudan Mine Underground Lab in northern Minnesota. The detectors are magnetized iron/scintillator calorimeters. The Far Detector has been operational for cosmic ray and atmospheric neutrino data from July of 2003, the Near Detector from September 2004, and the NuMI beam started in early 2005. This poster presents details of the two detectors.

  14. GADRAS Detector Response Function.

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Dean J.; Harding, Lee; Thoreson, Gregory G; Horne, Steven M.

    2014-11-01

    The Gamma Detector Response and Analysis Software (GADRAS) applies a Detector Response Function (DRF) to compute the output of gamma-ray and neutron detectors when they are exposed to radiation sources. The DRF is fundamental to the ability to perform forward calculations (i.e., computation of the response of a detector to a known source), as well as the ability to analyze spectra to deduce the types and quantities of radioactive material to which the detectors are exposed. This document describes how gamma-ray spectra are computed and the significance of response function parameters that define characteristics of particular detectors.

  15. The TALE Tower Detector

    Science.gov (United States)

    Bergman, D. R.

    The TA Low Energy Extension will include a Tower FluorescenceDetector. Extensive air showers at the lowest usful energies for fluorescence detectors will in general be close to the detector. This requires viewing all elevation angles to be able to reconstruct showers. The TALE Tower Detector, operating in conjunction with other TALE detectors will view elevation angles up to above 70 degrees, with an azimuthal coverage of about 90 degrees. Results from a prototype mirror operated in conjunction with the HiRes detector will also be presented.

  16. Hf impurity and defect interactions in helium-implanted NiHf

    Energy Technology Data Exchange (ETDEWEB)

    Govindaraj, R. E-mail: govind@igcar.ernet.in; Gopinathan, K.P.; Viswanathan, B

    2001-07-01

    TDPAC measurements on the reference and untreated sample indicate a loss in anisotropy which is attributed mainly to the association of probe atoms with defects produced by (n,{gamma}) reactions with isotopes of Ni and experiencing combined magnetic and quadrupole interactions of comparable strengths. Evolution of defect free and substitutional fraction of probe atoms experiencing Larmor frequency characteristic of Ni matrix has been studied as a function of isochronal annealing temperature in helium free {alpha}-irradiated and homogeneously helium-implanted samples. No defect associated Larmor precession frequency and/or quadrupole frequency could be deduced in these uncorrelated damage studies. Comparison of recovery stages in {alpha}-irradiated and helium-implanted samples indicates the binding of helium associated defects by Hf impurities. Segregation of Hf atoms is observed in the helium free {alpha}-irradiated sample for annealing treatment at 973 K, while no such effect is observed in the helium-implanted sample for isochronal annealing treatments up to 1273 K.

  17. Reconciliation of the excess 176Hf conundrum in meteorites: Recent disturbances of the Lu-Hf and Sm-Nd isotope systematics

    Science.gov (United States)

    Bast, Rebecca; Scherer, Erik E.; Sprung, Peter; Mezger, Klaus; Fischer-Gödde, Mario; Taetz, Stephan; Böhnke, Mischa; Schmid-Beurmann, Hinrich; Münker, Carsten; Kleine, Thorsten; Srinivasan, Gopalan

    2017-09-01

    The long-lived 176Lu-176Hf and 147Sm-143Nd radioisotope systems are commonly used chronometers, but when applied to meteorites, they can reveal disturbances. Specifically, Lu-Hf isochrons commonly yield dates up to ∼300 Myr older than the solar system and varying initial 176Hf/177Hf values. We investigated this problem by attempting to construct mineral and whole rock isochrons for eucrites and angrites. Meteorites from different parent bodies exhibit similar disturbance features suggesting that a common process is responsible. Minerals scatter away from isochron regressions for both meteorite classes, with low-Hf phases such as plagioclase and olivine typically being most displaced above (or left of) reference isochrons. Relatively Hf-rich pyroxene is less disturbed but still to the point of steepening Lu-Hf errorchrons. Using our Lu-Hf and Sm-Nd data, we tested various Hf and Lu redistribution scenarios and found that decoupling of Lu/Hf from 176Hf/177Hf must postdate the accumulation of significant radiogenic 176Hf. Therefore early irradiation or diffusion cannot explain the excess 176Hf. Instead, disturbed meteorite isochrons are more likely caused by terrestrial weathering, contamination, or common laboratory procedures. The partial dissolution of phosphate minerals may predominantly remove rare earth elements including Lu, leaving relatively immobile and radiogenic Hf behind. Robust Lu-Hf (and improved Sm-Nd) meteorite geochronology will require the development of chemical or physical methods for removing unsupported radiogenic Hf and silicate-hosted terrestrial contaminants without disturbing parent-daughter ratios.

  18. Tracking magmatic processes through Zr/Hf ratios in rocks and Hf and Ti zoning in zircons: An example from the Spirit Mountain batholith, Nevada

    Science.gov (United States)

    Lowery, Claiborne L.E.; Miller, C.F.; Walker, B.A.; Wooden, J.L.; Mazdab, F.K.; Bea, F.

    2006-01-01

    Zirconium and Hf are nearly identical geochemically, and therefore most of the crust maintains near-chondritic Zr/Hf ratios of ???35-40. By contrast, many high-silica rhyolites and granites have anomalously low Zr/Hf (15-30). As zircon is the primary reservoir for both Zr and Hf and preferentially incorporates Zr, crystallization of zircon controls Zr/ Hf, imprinting low Zr/Hf on coexisting melt. Thus, low Zr/Hf is a unique fingerprint of effective magmatic fractionation in the crust. Age and compositional zonation in zircons themselves provide a record of the thermal and compositional histories of magmatic systems. High Hf (low Zr/ Hf) in zircon zones demonstrates growth from fractionated melt, and Ti provides an estimate of temperature of crystallization (TTiZ) (Watson and Harrison, 2005). Whole-rock Zr/Hf and zircon zonation in the Spirit Mountain batholith, Nevada, document repeated fractionation and thermal fluctuations. Ratios of Zr/Hf are ???30-40 for cumulates and 18-30 for high-SiO2 granites. In zircons, Hf (and U) are inversely correlated with Ti, and concentrations indicate large fluctuations in melt composition and TTiZ (>100??C) for individual zircons. Such variations are consistent with field relations and ion-probe zircon geochronology that indicate a >1 million year history of repeated replenishment, fractionation, and extraction of melt from crystal mush to form the low Zr/Hf high-SiO2 zone. ?? 2006 The Mineralogical Society.

  19. Structural, electrical, band alignment and charge trapping analysis of nitrogen-annealed Pt/HfO2/p-Si (100) MIS devices

    Science.gov (United States)

    Kumar, Arvind; Mondal, Sandip; Rao, K. S. R. Koteswara

    2016-12-01

    Low leakage current density and high relative permittivity (dielectric constant) are the key factor in order to replace the SiO2 from Si-based technology toward its further downscaling. HfO2 thin films received significant attention due to its excellent optoelectronic properties. In this work, ultra-thin (17 nm) HfO2 films on Si substrate are fabricated by RF sputtering. As deposited films are amorphous in nature and in order to get the reasonable high dielectric constant, the films are annealed (700 °C, 30 min) in nitrogen environment. A high refractive index (2.08) and small grain size ( 10) nm were extracted from ellipsometry and XRD, respectively. The AFM study revealed a small RMS surface roughness 9 Å. For electrical characterization, films are integrated in metal-insulator-semiconductor capacitors structure. The oxide capacitance ( C ox), flat band capacitance ( C FB), flat band voltage ( V FB), and oxide-trapped charges ( Q ot) calculated from high-frequency (1 MHz) C- V curve are 490, 241 pF, 1.21 V and 1.8 × 1012 cm-2, respectively. The dielectric constant calculated from accumulation capacitance is 17. The films show a low leakage current density 6.8 × 10-9 A/cm2 at +1 V, and this is due to the reduction in oxygen vacancies concentration as we performed annealing in N2 environment. The band gap of the films is estimated from O 1 s loss spectra and found 5.7 eV. The electron affinity ( χ) and HfO2/Si barrier height (conduction band offset) extracted from UPS spectra are 1.88 and 2.17 eV, respectively. A trap state with 0.99 eV activation energy below the conduction band edge is found and assigned to the fourfold coordinated oxygen vacancy in m-HfO2.

  20. Determination of isothermal section of Ni-Re-Hf ternary system at 1173 K

    Institute of Scientific and Technical Information of China (English)

    王日初; 柳春雷; 金展鹏

    2002-01-01

    The phase equilibriua in the Ni-Re-Hf ternary system at 1173K were investigated by means of diffusion triple technique and electron microprobe analysis(EMPA). The experimental results indicate that two ternary intermetallics (α and β) and five binary intermetallics (Ni3Hf, Ni10Hf7, Ni11Hf9, NiHf and NiHf2) exist in the Ni-Re-Hf system at 1173 K. A tentative isothermal section of this system at 1173 K was constructed on the basis of experimental results. The isothermal section consists of nine three-phase regions, five of which are supported by the experimental data.

  1. Evaluation of signal energy calculation methods for a light-sharing SiPM-based PET detector

    Science.gov (United States)

    Wei, Qingyang; Ma, Tianyu; Xu, Tianpeng; Liu, Yaqiang; Wang, Shi; Gu, Yu

    2017-03-01

    Signals of a light-sharing positron emission tomography (PET) detector are commonly multiplexed to three analog pulses (E, X, and Y) and then digitally sampled. From this procedure, the signal energy that are critical to detector performance are obtained. In this paper, different signal energy calculation strategies for a self-developed SiPM-based PET detector, including pulse height and different integration methods, are evaluated in terms of energy resolution and spread of the crystal response in the flood histogram using a root-mean-squared (RMS) index. Results show that integrations outperform the pulse height. Integration using the maximum derivative value of the pulse E as the landmark point and 28 integrated points (448 ns) has the best performance in these evaluated methods for our detector. Detector performance in terms of energy and position is improved with this integration method. The proposed methodology is expected to be applicable for other light-sharing PET detectors.

  2. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I.; Martinez laso, L.

    1989-07-01

    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs.

  3. Advanced Virgo: a 2nd generation interferometric gravitational wave detector

    CERN Document Server

    ,

    2014-01-01

    Advanced Virgo is the project to upgrade the Virgo interferometric detector of gravitational waves, with the aim of increasing the number of observable galaxies (and thus the detection rate) by three orders of magnitude. The project is now in an advanced construction phase and the assembly and integration will be completed by the end of 2015. Advanced Virgo will be part of a network with the two Advanced LIGO detectors in the US and GEO HF in Germany, with the goal of contributing to the early detections of gravitational waves and to opening a new observation window on the universe. In this paper we describe the main features of the Advanced Virgo detector and outline the status of the construction.

  4. Spallation and fission products in the (p+{sup 179}Hf) and (p+{sup nat}Hf) reactions

    Energy Technology Data Exchange (ETDEWEB)

    Karamian, S.A. [Joint Institute for Nuclear Research, Moscow Region, Dubna 141980 (Russian Federation); Ur, C.A. [Horia Hulubei National Institute of Physics and Nuclear Engineering, P.O. Box MG-6, Bucharest 077125 (Romania); Induced Gamma Emission Foundation, P.O. Box 34-81, Bucharest 010044 (Romania)], E-mail: ur@pd.infn.it; Adam, J. [Joint Institute for Nuclear Research, Moscow Region, Dubna 141980 (Russian Federation); Institute of Nuclear Physics, Rez, Prague CZ-25068 (Czech Republic); Kalinnikov, V.G.; Lebedev, N.A.; Vostokin, G.K. [Joint Institute for Nuclear Research, Moscow Region, Dubna 141980 (Russian Federation); Collins, C.B. [Center for Quantum Electronics, University of Texas at Dallas, Richardson, TX 75083 (United States); Popescu, I.I. [Induced Gamma Emission Foundation, P.O. Box 34-81, Bucharest 010044 (Romania)

    2009-03-01

    Production of Hf and Lu high-spin isomers has been experimentally studied in spallation reactions induced by intermediate energy protons. Targets of enriched {sup 179}Hf (91%) and {sup nat}Hf were bombarded with protons of energy in the range from 90 to 650 MeV provided by the internal beam of the Dubna Phasotron synchrocyclotron. The activation yields of the reaction products were measured by using the {gamma}-ray spectroscopy and radiochemistry methods. The production cross-sections obtained for the {sup 179m2}Hf, {sup 178m2}Hf and {sup 177m}Lu isomers are similar to the previously measured values from the spallation of Ta, Re and W targets. Therefore, the reactions involving emission of only a few nucleons, like (p,p'), (p,p'n) and (p,2pn), can transfer high enough angular momentum to the final residual nuclei with reasonable large cross-sections. A significant gain in the isomeric yields was obtained when enriched {sup 179}Hf targets were used. The mass distribution of the residual nuclei was measured over a wide range of masses and the fission-to-spallation ratio could be deduced as a function of the projectile energy. Features of the reaction mechanism are briefly discussed.

  5. DEVELOPMENT OF A HIGH RATE HIGH RESOLUTION DETECTOR FOR EXAFS EXPERIMENTS.

    Energy Technology Data Exchange (ETDEWEB)

    DE GERONIMO,G.; O CONNOR,P.; BEUTTENMULLER,R.H.; LI,Z.; KUCZEWSKI,A.J.; SIDDONS,D.P.

    2002-11-10

    A new detector for EXAFS experiments is being developed. It is based on a multi-element Si sensor and dedicated readout ASICs. The sensor is composed of 384 pixels, each having 1 mm{sup 2} area, arranged in four quadrants of 12 x 8 elements, and wire-bonded to 32-channel front-end ASICs. Each channel implements low noise preamplification with self-adaptive continuous reset, high order shaper, band-gap referenced baseline stabilizer, one threshold comparator and two DAC adjustable window comparators, each followed by a 24-bit counter. Fabricated in 0.35{micro}m CMOS dissipates about 8mW per channel. First measurements show at room temperature a resolution of 14 rms electrons without the detector and of 40 rms electrons (340eV) with the detector connected and biased. Cooling at -35C a FWHM of 205eV (167eV from electronics) was measured at the Mn-K{alpha} line. A resolution of about 300eV was measured for rates approaching 100kcps/cm{sup 2} per channel, corresponding to an overall rate in excess of 10MHz/cm{sup 2}. A channel-to-channel threshold dispersion after DACs adjustment of 2.5 rms electrons was also measured.

  6. Thermal kinetic inductance detector

    Energy Technology Data Exchange (ETDEWEB)

    Cecil, Thomas; Gades, Lisa; Miceli, Antonio; Quaranta, Orlando

    2016-12-20

    A microcalorimeter for radiation detection that uses superconducting kinetic inductance resonators as the thermometers. The detector is frequency-multiplexed which enables detector systems with a large number of pixels.

  7. Forward tracking detectors

    Indian Academy of Sciences (India)

    Klaus Mönig

    2007-11-01

    Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  8. The OSMOND detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Dalgliesh, R. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.uk [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Holt, S.A.; Kinane, C.J. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Spill, E.J.; Stephenson, R. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom)

    2013-01-11

    The development and testing of the Off Specular MicrOstrip Neutron Detector (OSMOND) is described. Based on a microstrip gas chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing rate limited scintillator detectors currently in use on the CRISP reflectometer for off specular reflectometry experiments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  9. Hf-Nd isotope and trace element constraints on subduction inputs at island arcs: Limitations of Hf anomalies as sediment input indicators

    Science.gov (United States)

    Handley, Heather K.; Turner, Simon; Macpherson, Colin G.; Gertisser, Ralf; Davidson, Jon P.

    2011-04-01

    New Nd-Hf isotope and trace element data for Javanese volcanoes are combined with recently published data to place constraints on subduction inputs at the Sunda arc in Indonesia and assess the value of Hf anomalies (expressed as Hf/Hf* and Sm/Hf ratios) as tracers of such inputs. Hf anomaly does not correlate with Hf isotope ratio in Javanese lavas, however, Hf/Hf* and Sm/Hf ratios do correlate with SiO 2. Contrary to previous work, we show that Hf anomaly variation may be controlled by fractionation of clinopyroxene and/or amphibole during magmatic differentiation and does not represent the magnitude or type of subduction input in some arcs. Correlation of Sm/Hf with indices of differentiation for other arcs (e.g., Vanuatu, New Britain, and Mariana) suggests that differentiation control on Sm/Hf ratios in volcanic arc rocks may be a relatively common phenomenon. This study corroborates the use of Nd-Hf isotope co-variations in arc volcanic rocks to ascertain subduction input characteristics. The trajectories of regional volcano groups (East, Central and West Java) in Nd-Hf isotope space reveal heterogeneity in the subducted sediment input along Java, which reflects present-day spatial variations in sediment compositions on the down-going plate in the Java Trench. The high Sm/Hf ratio required in the sediment end-member for some Javanese basalts suggests that partial melting of subducted sediment occurs in the presence of residual zircon, and is inconsistent with residual monazite or allanite.

  10. Investigation and Development of Data-Driven D-Region Model for HF Systems Impacts

    Science.gov (United States)

    Eccles, J. V.; Rice, D.; Sojka, J. J.; Hunsucker, R. D.

    2002-01-01

    Space Environment Corporation (SEC) and RP Consultants (RPC) are to develop and validate a weather-capable D region model for making High Frequency (HF) absorption predictions in support of the HF communications and radar communities. The weather-capable model will assimilate solar and earth space observations from NASA satellites. The model will account for solar-induced impacts on HF absorption, including X-rays, Solar Proton Events (SPE's), and auroral precipitation. The work plan includes: I . Optimize D-region model to quickly obtain ion and electron densities for proper HF absorption calculations. 2. Develop indices-driven modules for D-region ionization sources for low, mid, & high latitudes including X-rays, cosmic rays, auroral precipitation, & solar protons. (Note: solar spectrum & auroral modules already exist). 3. Setup low-cost monitors of existing HF beacons and add one single-frequency beacon. 4. Use PENEX HF-link database with HF monitor data to validate D-region/HF absorption model using climatological ionization drivers. 5. Develop algorithms to assimilate NASA satellite data of solar, interplanetary, and auroral observations into ionization source modules. 6. Use PENEX HF-link & HF-beacon data for skill score comparison of assimilation versus climatological D-region/HF absorption model. Only some satellites are available for the PENEX time period, thus, HF-beacon data is necessary. 7. Use HF beacon monitors to develop HF-link data assimilation algorithms for regional improvement to the D-region/HF absorption model.

  11. Serpentinization Changes Nd, but not Hf Isotopes of Abyssal Peridotites

    Science.gov (United States)

    Bizimis, M.; Frisby, C. P.; Mallick, S.

    2015-12-01

    Serpentinization of the oceanic lithosphere is a known sink for fluid mobile elements (B, Cl, Li, Sr, etc.), while high field strength elements (HFSE: e.g., Hf, Zr, Ti, Nb) are thought to be unaffected by it. In contrast, the fate of REE during serpentinization is equivocal. Correlations between REE and HFSE concentrations in abyssal peridotites suggest control by magmatic processes (Niu, 2004, J. Pet), while some LREE enrichments in serpentinized peridotites compared to their clinopyroxene (cpx) and Nd, Sr isotope data (Delacour et al., 2008, Chem. Geol.) imply seawater-derived REE addition to the mantle protolith (Paulick et al., 2006, Chem. Geol). To further constrain peridotite-seawater interaction during serpentinization we compare bulk rock and cpx Hf and Nd isotope data in partially (up to ~70%) serpentinized abyssal peridotites (9-16°E South West Indian Ridge). We also present a new method that improves yields in Hf, Nd and Pb separations from depleted (90% of Hf, Zr, Ti are retained in the residue. LA-ICPMS data shows that serpentine after olivine typically has higher LREE/HREE ratios than cpx, pronounced negative Ce anomalies, high U, Sr concentrations and low HFSE, unlike the coexisting cpx. These data are consistent with some seawater-derived LREE addition to peridotite during serpentinization, localized in the serpentine and other secondary phases, while cpx retains the magmatic value. This process will lower the Sm/Nd relative to Lu/Hf ratio in the peridotite and can lead to decoupled radiogenic Hf and unradiogenic Nd isotopes upon recycling and aging. Our data further testifies to the fidelity of Hf isotopes in tracing mantle processes, even in serpentinized rocks.

  12. The CAPRICE RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Codino, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata` Rome (Italy); Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.; Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy)

    1995-09-01

    A compact RICH detector has been developed and used for particle identification in a balloon borne spectrometer to measure the flux of antimatter in the cosmic radiation. This is the first RICH detector ever used in space experiments that is capable of detecting unit charged particles, such as antiprotons. The RICH and all other detectors performed well during the 27 hours long flight.

  13. Joint Efforts Towards European HF Radar Integration

    Science.gov (United States)

    Rubio, A.; Mader, J.; Griffa, A.; Mantovani, C.; Corgnati, L.; Novellino, A.; Schulz-Stellenfleth, J.; Quentin, C.; Wyatt, L.; Ruiz, M. I.; Lorente, P.; Hartnett, M.; Gorringe, P.

    2016-12-01

    During the past two years, significant steps have been made in Europe for achieving the needed accessibility to High Frequency Radar (HFR) data for a pan-European use. Since 2015, EuroGOOS Ocean Observing Task Teams (TT), such as HFR TT, are operational networks of observing platforms. The main goal is on the harmonization of systems requirements, systems design, data quality, improvement and proof of the readiness and standardization of HFR data access and tools. Particular attention is being paid by HFR TT to converge from different projects and programs toward those common objectives. First, JERICO-NEXT (Joint European Research Infrastructure network for Coastal Observatory - Novel European eXpertise for coastal observaTories, H2020 2015 Programme) will contribute on describing the status of the European network, on seeking harmonization through exchange of best practices and standardization, on developing and giving access to quality control procedures and new products, and finally on demonstrating the use of such technology in the general scientific strategy focused by the Coastal Observatory. Then, EMODnet (European Marine Observation and Data Network) Physics started to assemble HF radar metadata and data products within Europe in a uniform way. This long term program is providing a combined array of services and functionalities to users for obtaining free of charge data, meta-data and data products on the physical conditions of European sea basins and oceans. Additionally, the Copernicus Marine Environment Monitoring Service (CMEMS) delivers from 2015 a core information service to any user related to 4 areas of benefits: Maritime Safety, Coastal and Marine Environment, Marine Resources, and Weather, Seasonal Forecasting and Climate activities. INCREASE (Innovation and Networking for the integration of Coastal Radars into EuropeAn marine SErvices - CMEMS Service Evolution 2016) will set the necessary developments towards the integration of existing European

  14. First-principles study of the Hf-based Heusler alloys: Hf2CoGa and Hf2CoIn

    Science.gov (United States)

    Hu, Yan; Zhang, Jian-Min

    2017-01-01

    The electronic structures and magnetic properties of the new Heusler alloys Hf2CoGa and Hf2CoIn have been studied by using the first-principles projector augmented wave (PAW) potential within the generalized gradient approximation (GGA). Both Hf2CoGa and Hf2CoIn Heusler alloys have the half-metallic character and completely (100%) spin polarization at the Fermi level (EF) and the indirect band gaps of 0.733 eV and 0.654 eV, respectively, in the minority spin channel. The total magnetic moments μt are all 2μB per formula unit, linearly scaled with the total number of valence electrons (Zt) by μt=Zt-18 and the atomic magnetic moments have localized character due to less affected by deformations. The origin of the indirect band gaps for these two new Heusler alloys is well understood. These two new Heusler alloys are the ideal candidates for spintronic devices.

  15. Energy dependence of r.m.s amplitude of low frequency broadband noise and kHz quasi periodic oscillations in 4U 1608-52

    Science.gov (United States)

    Mandal, Soma

    2016-07-01

    The neutron star low mass X-ray binary 4U 1608-52 is known to show kHz QPOs as well as low frequency broad band noise. The energy dependence of the fractional r.m.s of these variations reflect the underlying radiative mechanism responsible for the phenomena. In this work we compute the energy depedence for 26 instances of kHz QPO observed by RXTE. We typically find as reported before, that the r.m.s increases with energy with slope of ˜0.5. This indicates that the variation is in the hot thermal compotonization component and in particular the QPO is likely to be driven by variation in the thermal heating rate of the hot plasma. For the same data, we compute the energy dependent r.m.s variability of the low frequency broad band noise component by considering the light curves. In contrast to the behaviour seen for the kHz QPO, the energy dependence is nearly flat i.e. the r.m.s. is energy independent. This indicates that the driver here may be the soft photon source. Thus the radiative mechanism driving the low frequency broad band noise and the high frequency QPO are different in nature.

  16. Enhancing Learning in Statistics Classes Through The Use of Concrete Historical Examples: The Space Shuttle Challenger, Pearl Harbor, and the RMS Titanic.

    Science.gov (United States)

    Schumm, Walter R.; Webb, Farrell J.; Castelo, Carlos S.; Akagi, Cynthia G.; Jensen, Erick J.; Ditto, Rose M.; Spencer Carver, Elaine; Brown, Beverlyn F.

    2002-01-01

    Discusses the use of historical events as examples for teaching college level statistics courses. Focuses on examples of the space shuttle Challenger, Pearl Harbor (Hawaii), and the RMS Titanic. Finds real life examples can bridge a link to short term experiential learning and provide a means for long term understanding of statistics. (KDR)

  17. HF omnidirectional spectral CW auroral radar (HF-OSCAR) at very high latitude. Part 1: Technique

    Science.gov (United States)

    Olesen, J. K.; Jacobsen, K. E.; Stauning, P.; Henriksen, S.

    1983-12-01

    An HF system for studies of very high latitude ionospheric irregularities was described. Radio aurora from field-aligned E-region irregularities of the Slant E Condition type were discussed. The complete system combines an ionosonde, a 12 MHz pulse radar and a 12 MHz bistatic CW Doppler-range set-up. The two latter units use alternately a 360 deg rotating Yagi antenna. High precision oscillators secure the frequency stability of the Doppler system in which the received signal is mixed down to a center frequency of 500 Hz. The Doppler shift range is max + or - 500 Hz. The received signal is recorded in analog form on magnetic tape and may be monitored visually and audibly. Echo range of the CW Doppler signal is obtained by a 150 Hz amplitude modulation of the transmitted signal and phase comparison with the backscattered signal.

  18. Comparison of HfAlO, HfO2/Al2O3, and HfO2 on n-type GaAs using atomic layer deposition

    Science.gov (United States)

    Lu, Bin; Lv, Hongliang; Zhang, Yuming; Zhang, Yimen; Liu, Chen

    2016-11-01

    Different high-permittivity (high-k) gate dielectric structures of HfO2, HfAlO, and HfO2/Al2O3 deposited on HF-etched n-GaAs using ALD have been investigated. It has been demonstrated that the stacked structure of HfO2/Al2O3 has the lowest interface state density of 8.12 × 1012eV-1 cm-2 due to the "self-cleaning" reaction process, but the sample of HfAlO shows much better frequency dispersion and much higher dielectric permittivity extracted from the C-V curves. The investigation reveals that the electrical properties of gate dielectrics are improved by introducing alumina into HfO2.

  19. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science.

    Science.gov (United States)

    Jungmann-Smith, J H; Bergamaschi, A; Brückner, M; Cartier, S; Dinapoli, R; Greiffenberg, D; Huthwelker, T; Maliakal, D; Mayilyan, D; Medjoubi, K; Mezza, D; Mozzanica, A; Ramilli, M; Ruder, Ch; Schädler, L; Schmitt, B; Shi, X; Tinti, G

    2016-03-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system.

  20. Effects of vacuum ultraviolet photons, ion energy and substrate temperature on line width roughness and RMS surface roughness of patterned 193 nm photoresist

    Science.gov (United States)

    Titus, M. J.; Graves, D. B.; Yamaguchi, Y.; Hudson, E. A.

    2011-03-01

    We present a comparison of patterned 193 nm photoresist (PR) line width roughness (LWR) of samples processed in a well characterized argon (Ar) inductively coupled plasma (ICP) system to RMS surface roughness and bulk chemical modification of blanket 193 nm PR samples used as control samples. In the ICP system, patterned and blanket PR samples are irradiated with Ar vacuum ultraviolet photons (VUV) and Ar ions while sample temperature, photon flux, ion flux and ion energy are controlled and measured. The resulting chemical modifications to bulk 193 nm PR (blanket) and surface roughness are analysed with Fourier transform infrared spectroscopy and atomic force microscopy (AFM). LWR of patterned samples are measured with scanning electron microscopy and blanket portions of the patterned PRs are measured with AFM. We demonstrate that with no RF-bias applied to the substrate the LWR of 193 nm PR tends to smooth and correlates with the smoothing of the RMS surface roughness. However, both LWR and RMS surface roughness increases with simultaneous high-energy (>=70 eV) ion bombardment and VUV-irradiation and is a function of exposure time. Both high- and low-frequency LWR correlate well with the RMS surface roughness of the patterned and blanket 193 nm PR samples. LWR, however, does not increase with temperatures ranging from 20 to 80 °C, in contrast to the RMS surface roughness which increases monotonically with temperature. It is unclear why LWR remains independent of temperature over this range. However, the fact that blanket roughness and LWR on patterned samples, both scale similarly with VUV fluence and ion energy suggests a similar mechanism is responsible for both types of surface morphology modifications.

  1. Effects of vacuum ultraviolet photons, ion energy and substrate temperature on line width roughness and RMS surface roughness of patterned 193 nm photoresist

    Energy Technology Data Exchange (ETDEWEB)

    Titus, M J; Graves, D B [Department of Chemical Engineering, University of California, Berkeley, CA 94720 (United States); Yamaguchi, Y; Hudson, E A, E-mail: graves@berkeley.edu [Lam Research Corporation, 4400 Cushing Parkway, Freemont, CA 94538 (United States)

    2011-03-02

    We present a comparison of patterned 193 nm photoresist (PR) line width roughness (LWR) of samples processed in a well characterized argon (Ar) inductively coupled plasma (ICP) system to RMS surface roughness and bulk chemical modification of blanket 193 nm PR samples used as control samples. In the ICP system, patterned and blanket PR samples are irradiated with Ar vacuum ultraviolet photons (VUV) and Ar ions while sample temperature, photon flux, ion flux and ion energy are controlled and measured. The resulting chemical modifications to bulk 193 nm PR (blanket) and surface roughness are analysed with Fourier transform infrared spectroscopy and atomic force microscopy (AFM). LWR of patterned samples are measured with scanning electron microscopy and blanket portions of the patterned PRs are measured with AFM. We demonstrate that with no RF-bias applied to the substrate the LWR of 193 nm PR tends to smooth and correlates with the smoothing of the RMS surface roughness. However, both LWR and RMS surface roughness increases with simultaneous high-energy ({>=}70 eV) ion bombardment and VUV-irradiation and is a function of exposure time. Both high- and low-frequency LWR correlate well with the RMS surface roughness of the patterned and blanket 193 nm PR samples. LWR, however, does not increase with temperatures ranging from 20 to 80 deg. C, in contrast to the RMS surface roughness which increases monotonically with temperature. It is unclear why LWR remains independent of temperature over this range. However, the fact that blanket roughness and LWR on patterned samples, both scale similarly with VUV fluence and ion energy suggests a similar mechanism is responsible for both types of surface morphology modifications.

  2. Mechanical properties of cast Ti-Hf alloys.

    Science.gov (United States)

    Sato, Hideki; Kikuchi, Masafumi; Komatsu, Masashi; Okuno, Osamu; Okabe, Toru

    2005-02-15

    This study examined the mechanical properties of a series of Ti-Hf alloys. Titanium alloys with 10 to 40 mass % Hf were made with titanium and hafnium sponge in an argon-arc melting furnace. Specimens cast into magnesia-based investment molds were tested for yield strength, tensile strength, percentage elongation, and modulus of elasticity. Vickers microhardness was determined at 25 to 600 microm from the cast surface. X-ray diffractometry was also performed. Commercially pure Ti (CP Ti) and pure Ti prepared from titanium sponge were used as controls. The data (n = 5) were analyzed with a one-way ANOVA and the Student-Newman-Keuls test (alpha = 0.05). The diffraction peaks of all the metals matched those for alpha Ti; no beta phase peaks were found. Alloys with Hf > or = 25% had significantly (p 0.05) in elongation among all the Ti-Hf alloys and CP Ti, whereas the elongation of alloys with Hf > or = 30% was significantly (p alloys tested can be considered viable alternatives to CP Ti because they were stronger than CP Ti and had similar elongation.

  3. Equalized near maximum likelihood detector

    OpenAIRE

    2012-01-01

    This paper presents new detector that is used to mitigate intersymbol interference introduced by bandlimited channels. This detector is named equalized near maximum likelihood detector which combines nonlinear equalizer and near maximum likelihood detector. Simulation results show that the performance of equalized near maximum likelihood detector is better than the performance of nonlinear equalizer but worse than near maximum likelihood detector.

  4. Toward Single Electron Resolution Phonon Mediated Ionization Detectors

    CERN Document Server

    Mirabolfathi, Nader; Mahapatra, Rupak; Sundqvist, Kyle; Jastram, Andrew; Serfass, Bruno; Faiez, Dana; Sadoulet, Bernard

    2015-01-01

    Experiments seeking to detect rare event interactions such as dark matter or coherent elastic neutrino nucleus scattering are striving for large mass detectors with very low detection threshold. Using Neganov-Luke phonon amplification effect, the Cryogenic Dark Matter Search (CDMS) experiment is reaching unprecedented RMS resolutions of ~ 14 eV$_{ee}$ . CDMSlite is currently the most sensitive experiment to WIMPs of mass $\\sim$5 GeV/c$^{2}$ but is limited in achieving higher phonon gains due to an early onset of leakage current into Ge crystals. The contact interface geometry is particularly weak for blocking hole injection from the metal, and thus a new design is demonstrated that allows high voltage bias via vacuum separated electrode. With an increased bias voltage and a $\\times$ 2 Luke phonon gain, world best RMS resolution of sigma $\\sim$7 eV$_{ee}$ for 0.25 kg (d=75 mm, h=1 cm) Ge detectors was achieved. Since the leakage current is a function of the field and the phonon gain is a function of the applie...

  5. High-energy detector

    Science.gov (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  6. Laboratory and test beam results from a large-area silicon drift detector

    CERN Document Server

    Bonvicini, V; Giubellino, P; Gregorio, A; Idzik, M; Kolojvari, A A; Montaño-Zetina, L M; Nouais, D; Petta, C; Rashevsky, A; Randazzo, N; Reito, S; Tosello, F; Vacchi, A; Vinogradov, L I; Zampa, N

    2000-01-01

    A very large-area (6.75*8 cm/sup 2/) silicon drift detector with integrated high-voltage divider has been designed, produced and fully characterised in the laboratory by means of ad hoc designed MOS injection electrodes. The detector is of the "butterfly" type, the sensitive area being subdivided into two regions with a maximum drift length of 3.3 cm. The device was also tested in a pion beam (at the CERN PS) tagged by means of a microstrip detector telescope. Bipolar VLSI front-end cells featuring a noise of 250 e/sup -/ RMS at 0 pF with a slope of 40 e/sup -//pF have been used to read out the signals. The detector showed an excellent stability and featured the expected characteristics. Some preliminary results will be presented. (12 refs).

  7. HfO2 Gate Dielectrics for Future Generation of CMOS Device Application

    Institute of Scientific and Technical Information of China (English)

    H.Y.Yu; J.F.Kang; Ren Chi; M.F.Li; D.L.Kwong

    2004-01-01

    The material and electrical properties of HfO2 high-k gate dielectric are reported.In the first part,the band alignment of HfO2 and (HfO2)x(Al2O3)1-x to (100)Si substrate and their thermal stability are studied by X-ray photoelectron spectroscopy and TEM.The energy gap of (HfO2)x(Al2O3)1-x,the valence band offset,and the conduction band offset between (HfO2)x(Al2O3)1-x and the Si substrate as functions of x are obtained based on the XPS results.Our XPS results also demonstrate that both the thermal stability and the resistance to oxygen diffusion of HfO2 are improved by adding Al to form Hf aluminates.In the second part,a thermally stable and high quality HfN/HfO2 gate stack is reported.Negligible changes in equivalent oxide thickness (EOT),gate leakage,and work function (close to Si mid-gap) of HfN/HfO2 gate stack are demonstrated even after 1000℃ post-metal annealing(PMA),which is attributed to the superior oxygen diffusion barrier of HfN as well as the thermal stability of the HfN/HfO2 interface.Therefore,even without surface nitridation prior to HfO2 deposition,the EOT of HfN/HfO2 gate stack has been successfully scaled down to less than 1nm after 1000℃ PMA with excellent leakage and long-term reliability.The last part demonstrates a novel replacement gate process employing a HfN dummy gate and sub-1nm EOT HfO2 gate dielectric.The excellent thermal stability of the HfN/HfO2 gate stack enables its use in high temperature CMOS processes.The replacement of HfN with other metal gate materials with work functions adequate for n- and p-MOS is facilitated by a high etch selectivity of HfN with respect to HfO2,without any degradation to the EOT,gate leakage,or TDDB characteristics of HfO2.

  8. Pressure-induced novel compounds in the Hf-O system from first-principles calculations

    Science.gov (United States)

    Zhang, Jin; Oganov, Artem R.; Li, Xinfeng; Xue, Kan-Hao; Wang, Zhenhai; Dong, Huafeng

    2015-11-01

    Using first-principles evolutionary simulations, we have systematically investigated phase stability in the Hf-O system at pressure up to 120 GPa. New compounds Hf5O2,Hf3O2 , HfO, and HfO3 are discovered to be thermodynamically stable at certain pressure ranges. Two new high-pressure phases are found for Hf2O : one with space group Pnnm and anti-CaCl2-type structure, another with space group I 41/amd. Pnnm-HfO3 shows interesting structure, simultaneously containing oxide O2 - and peroxide [O-O]2 - anions. Remarkably, it is P 6 ¯2 m -HfO rather than OII-HfO2 that exhibits the highest mechanical characteristics among Hf-O compounds. Pnnm-Hf2O , Imm2-Hf5O2 ,P 3 ¯1 m -Hf2O , and P 4 ¯m 2 -Hf2O3 phases also show superior mechanical properties; theoretically these phases become metastable phases to ambient pressure and their properties can be exploited.

  9. Effect of HF leaching on 14C dates of pottery

    Science.gov (United States)

    Goslar, Tomasz; Kozłowski, Janusz; Szmyt, Marzena; Czernik, Justyna

    2013-01-01

    This paper presents the experiments with 14C dating of two potsherds, which contained carbon dispersed rather homogeneously in their clay fabric. After AAA treatment, the potsherds still appeared to be contaminated with young carbon, presumably connected with humic acids. To make removal of humic acids more effective, we treated the sherds with HF acid of different concentration. The 14C results obtained demonstrate that HF treatment indeed helps to remove humic contaminants, but it also mobilizes carbon bound to raw clay, which may make 14C dates too old. We conclude therefore, that using a simple combination of HF and AAA treatment seems insufficient in reliable 14C dating of carbon homogeneously dispersed in the volume of potsherds.

  10. The Status of Rotational Nonequilibrium in HF Chemical Lasers

    Science.gov (United States)

    1986-05-01

    later study from the same laboratory, Copeland et al. 5 3 used a NdYAG dye laser to pump HF into v = 2, j, and an HF pulsed laser to probe various P 2(J... Weston , Jr., J. Chem. Phys. 77, 4776 (1982). 51. J. J. Hinchen and R. H. Hobbs, Appl. Phys. 50, 628 (1979). 52. j. K. Lambert, G. M. Jursich, and F. F...Crim, Chem. Phys. Lett. 71, 258 (1980). 53. R. A. Copeland , D. J. Pearson, and F. F. Crim, Chem. Phys. Lett. 81, 541 (1981). 54. T. J. Foster and F. F

  11. New active load voltage clamp for HF-link converters

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.; Andersen, M.A.E.

    2005-07-01

    This paper proposes a new active clamp for HF-link converters, which features very high efficiency by returning the clamped energy back to the primary side through a small auxiliary converter. It also increases the reliability of HF-link converters by providing an alternative load current path during malfunctions of the secondary bidirectional bridge. The feasibility of the approach is shown on audio power amplifier prototype. New integrated magnetics design is presented that incorporates both the main power and auxiliary transformer on the same magnetic core. (au)

  12. HF-induced airglow at magnetic zenith: theoretical considerations

    Directory of Open Access Journals (Sweden)

    E. V. Mishin

    2005-01-01

    Full Text Available Observations of airglow at 630nm (red line and 557.7nm (green line during HF modification experiments at the High Frequency Active Auroral Research Program (HAARP heating facility are analyzed. We propose a theoretical framework for understanding the generation of Langmuir and ion acoustic waves during magnetic zenith injections. We show that observations of HF-induced airglow in an underdense ionosphere as well as a decrease in the height of the emitting volume are consistent with this scenario.

  13. HF-hash : Hash Functions Using Restricted HFE Challenge-1

    CERN Document Server

    Dey, Dhananjoy; Gupta, Indranath Sen

    2009-01-01

    Vulnerability of dedicated hash functions to various attacks has made the task of designing hash function much more challenging. This provides us a strong motivation to design a new cryptographic hash function viz. HF-hash. This is a hash function, whose compression function is designed by using first 32 polynomials of HFE Challenge-1 with 64 variables by forcing remaining 16 variables as zero. HF-hash gives 256 bits message digest and is as efficient as SHA-256. It is secure against the differential attack proposed by Chabaud and Joux as well as by Wang et. al. applied to SHA-0 and SHA-1.

  14. Hf--Co--B alloys as permanent magnet materials

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, Michael Alan; Rios, Orlando; Ghimire, Nirmal Jeevi

    2017-01-24

    An alloy composition is composed essentially of Hf.sub.2-XZr.sub.XCo.sub.11B.sub.Y, wherein 0Hf.sub.2-XZr.sub.XCo.sub.11B.sub.Y, wherein 0.ltoreq.X<2 and 0

  15. First HF radar measurements of summer mesopause echoes at SURA

    Directory of Open Access Journals (Sweden)

    A. N. Karashtin

    Full Text Available HF sounding of the mesosphere was first carried out at SURA in summer 1994 at frequencies in the range 8–9 MHz using one of the sub-arrays of the SURA heating facility. The observations had a range resolution of 3 km. Almost all measurements indicated the presence of strong radar returns from altitudes between 83 and 90 km with features very similar to VHF measurements of mesopause summer echoes at mid-latitudes and polar mesopause summer echoes. In contrast to VHF observations, HF mesopause echoes are almost always present.

  16. New active load voltage clamp for HF-link converters

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper proposes a new active clamp for HF-link converters, which features very high efficiency by returning the clamped energy back to the primary side through a small auxiliary converter. It also increases the reliability of HF-link converters by providing an alternative load current path du...... during malfunctions of the secondary bidirectional bridge. The feasibility of the approach is shown on audio power amplifier prototype. New integrated magnetics design is presented that incorporates both the main power and auxiliary transformer on the same magnetic core....

  17. First HF radar measurements of summer mesopause echoes at SURA

    Science.gov (United States)

    Karashtin, A. N.; Shlyugaev, Y. V.; Abramov, V. I.; Belov, I. F.; Berezin, I. V.; Bychkov, V. V.; Eryshev, E. B.; Komrakov, G. P.

    1997-07-01

    HF sounding of the mesosphere was first carried out at SURA in summer 1994 at frequencies in the range 8-9 MHz using one of the sub-arrays of the SURA heating facility. The observations had a range resolution of 3 km. Almost all measurements indicated the presence of strong radar returns from altitudes between 83 and 90 km with features very similar to VHF measurements of mesopause summer echoes at mid-latitudes and polar mesopause summer echoes. In contrast to VHF observations, HF mesopause echoes are almost always present.

  18. European coordination for coastal HF radar data in EMODnet Physics

    Science.gov (United States)

    Mader, Julien; Novellino, Antonio; Gorringe, Patrick; Griffa, Annalisa; Schulz-Stellenfleth, Johannes; Montero, Pedro; Montovani, Carlo; Ayensa, Garbi; Vila, Begoña; Rubio, Anna; Sagarminaga, Yolanda

    2015-04-01

    Historically, joint effort has been put on observing open ocean, organizing, homogenizing, sharing and reinforcing the impact of the acquired information based on one technology: ARGO with profilers Argo floats, EuroSites, ESONET-NoE, FixO3 for deep water platforms, Ferrybox for stations in ships of opportunities, and GROOM for the more recent gliders. This kind of networking creates synergies and makes easier the implementation of this source of data in the European Data exchange services like EMODnet, ROOSs portals, or any applied services in the Blue economy. One main targeted improvement in the second phase of EMODnet projects is the assembling of data along coastline. In that sense, further coordination is recommended between platform operators around a specific technology in order to make easier the implementation of the data in the platforms (4th EuroGOOS DATAMEQ WG). HF radar is today recognized internationally as a cost-effective solution to provide high spatial and temporal resolution current maps (depending on the instrument operation frequency, covering from a few kilometres offshore up to 200 km) that are needed for many applications for issues related to ocean surface drift or sea state characterization. Significant heterogeneity still exists in Europe concerning technological configurations, data processing, quality standards and data availability. This makes more difficult the development of a significant network for achieving the needed accessibility to HF Radar data for a pan European use. EuroGOOS took the initiative to lead and coordinate activities within the various observation platforms by establishing a number of Ocean Observing Task Teams such as HF-Radars. The purpose is to coordinate and join the technological, scientific and operational HF radar communities at European level. The goal of the group is on the harmonization of systems requirements, systems design, data quality, improvement and proof of the readiness and standardization of

  19. The DØ detector

    Science.gov (United States)

    Abachi, S.; Abolins, M.; Acharya, B. S.; Adam, I.; Ahn, S.; Aihara, H.; Alvarez, G.; Alves, G. A.; Amos, N.; Anderson, W.; Antipov, Yu.; Aronson, S. H.; Astur, R.; Avery, R. E.; Baden, A.; Balderston, J.; Baldin, B.; Bantly, J.; Barasch, E.; Bartlett, J. F.; Bazizi, K.; Behnke, T.; Bezzubov, V.; Bhat, P. C.; Blazey, G.; Blessing, S.; Boehnlein, A.; Borcherding, F.; Borders, J.; Bozko, N.; Brandt, A.; Brock, R.; Bross, A.; Buchholz, D.; Burtovoy, V.; Butler, J. M.; Callot, O.; Chakraborty, D.; Chekulaev, S.; Chen, J.; Chen, L.-P.; Chen, W.; Choudhary, B. C.; Christenson, J. H.; Claes, D.; Clark, A. R.; Cobau, W. G.; Cochran, J.; Cooper, W. E.; Cretsinger, C.; Cullen-Vidal, D.; Cummings, M.; Cutts, D.; Dahl, O. I.; Daniels, B.; De, K.; Demarteau, M.; Denisenko, K.; Denisenko, N.; Denisov, D.; Denisov, S.; Dharmaratna, W.; Diehl, H. T.; Diesburg, M.; Dixon, R.; Draper, P.; Ducros, Y.; Durston-Johnson, S.; Eartly, D.; Eberhard, P. H.; Edmunds, D.; Efimov, A.; Ellison, J.; Elvira, V. D.; Engelmann, R.; Eroshin, O.; Evdokimov, V.; Fahey, S.; Fanourakis, G.; Fatyga, M.; Featherly, J.; Feher, S.; Fein, D.; Ferbel, T.; Finley, D.; Finocchiaro, G.; Fisk, H. E.; Flattum, E.; Forden, G. E.; Fortner, M.; Franzini, P.; Fuess, S.; Gallas, E.; Gao, C. S.; Geld, T. L.; Genser, K.; Gerber, C. E.; Gibbard, B.; Glebov, V.; Glicenstein, J. F.; Gobbi, B.; Goforth, M.; Good, M. L.; Goozen, F.; Gordon, H.; Graf, N.; Grannis, P. D.; Green, D. R.; Green, J.; Greenlee, H.; Grossman, N.; Grudberg, P.; Guida, J. A.; Guida, J. M.; Guryn, W.; Hadley, N. J.; Haggerty, H.; Hagopian, S.; Hagopian, V.; Hall, R. E.; Hansen, S.; Hauptman, J.; Hedin, D.; Heinson, A. P.; Heintz, U.; Heuring, T.; Hirosky, R.; Hodel, K.; Hoftun, J. S.; Hubbard, J. R.; Huehn, T.; Huson, R.; Igarashi, S.; Ito, A. S.; James, E.; Jiang, J.; Johns, K.; Johnson, C. R.; Johnson, M.; Jonckheere, A.; Jones, M.; Jöstlein, H.; Jung, C. K.; Kahn, S.; Kanekal, S.; Kernan, A.; Kerth, L.; Kirunin, A.; Klatchko, A.; Klima, B.; Klochkov, B.; Klopfenstein, C.; Klyukhin, V.; Kochetkov, V.; Kohli, J. M.; Kononenko, W.; Kotcher, J.; Kotov, I.; Kourlas, J.; Kozelov, A.; Kozlovsky, E.; Krafczyk, G.; Krempetz, K.; Krishnaswamy, M. R.; Kroon, P.; Krzywdzinski, S.; Kunori, S.; Lami, S.; Landsberg, G.; Lanou, R. E.; Laurens, P.; Lee-Franzini, J.; Li, J.; Li, R.; Li-Demarteau, Q. Z.; Lima, J. G. R.; Linn, S. L.; Linnemann, J.; Lipton, R.; Liu, Y.-C.; Lloyd-Owen, D.; Lobkowicz, F.; Loken, S. C.; Lokos, S.; Lueking, L.; Maciel, A. K. A.; Madaras, R. J.; Madden, R.; Malamud, E.; Mangeot, Ph.; Manning, I.; Mansoulié, B.; Manzella, V.; Mao, H.-S.; Marcin, M.; Markosky, L.; Marshall, T.; Martin, H. J.; Martin, M. I.; Martin, P. S.; Marx, M.; May, B.; Mayorov, A.; McCarthy, R.; McKinley, J.; Mendoza, D.; Meng, X.-C.; Merritt, K. W.; Milder, A.; Mincer, A.; Mondal, N. K.; Montag, M.; Mooney, P.; Mudan, M.; Mulholland, G. T.; Murphy, C.; Murphy, C. T.; Nang, F.; Narain, M.; Narasimham, V. S.; Neal, H. A.; Nemethy, P.; Nešić, D.; Ng, K. K.; Norman, D.; Oesch, L.; Oguri, V.; Oltman, E.; Oshima, N.; Owen, D.; Pang, M.; Para, A.; Park, C. H.; Partridge, R.; Paterno, M.; Peryshkin, A.; Peters, M.; Pi, B.; Piekarz, H.; Pischalnikov, Yu.; Pizzuto, D.; Pluquet, A.; Podstavkov, V.; Pope, B. G.; Prosper, H. B.; Protopopescu, S.; Que, Y.-K.; Quintas, P. Z.; Rahal-Callot, G.; Raja, R.; Rajagopalan, S.; Rao, M. V. S.; Rasmussen, L.; Read, A. L.; Regan, T.; Repond, S.; Riadovikov, V.; Rijssenbeek, M.; Roe, N. A.; Rubinov, P.; Rutherfoord, J.; Santoro, A.; Sawyer, L.; Schamberger, R. D.; Sculli, J.; Selove, W.; Shea, M.; Shkurenkov, A.; Shupe, M.; Singh, J. B.; Sirotenko, V.; Smart, W.; Smith, A.; Smith, D.; Smith, R. P.; Snow, G. R.; Snyder, S.; Sosebee, M.; Souza, M.; Spadafora, A. L.; Stampke, S.; Stephens, R.; Stevenson, M. L.; Stewart, D.; Stocker, F.; Stoyanova, D.; Stredde, H.; Streets, K.; Strovink, M.; Suhanov, A.; Taketani, A.; Tartaglia, M.; Taylor, J. D.; Teiger, J.; Theodosiou, G.; Thompson, J.; Tisserant, S.; Trippe, T. G.; Tuts, P. M.; Van Berg, R.; Vaz, M.; Vishwanath, P. R.; Volkov, A.; Vorobiev, A.; Wahl, H. D.; Wang, D.-C.; Wang, L.-Z.; Weerts, H.; Wenzel, W. A.; White, A.; White, J. T.; Wightman, J.; Willis, S.; Wimpenny, S. J.; Wolf, Z.; Womersley, J.; Wood, D. R.; Xia, Y.; Xiao, D.; Xie, P.; Xu, H.; Yamada, R.; Yamin, P.; Yanagisawa, C.; Yang, J.; Yang, M.-J.; Yoshikawa, C.; Youssef, S.; Yu, J.; Zeller, R.; Zhang, S.; Zhou, Y. H.; Zhu, Q.; Zhu, Y.-S.; Zieminska, D.; Zieminski, A.; Zinchenko, A.; Zylberstejn, A.; DØ Collaboration

    1994-01-01

    The DØ detector is a large general purpose detector for the study of short-distance phenomena in high energy antiproton-proton collisions, now in operation at the Fermilab Tevatron collider. The detector focusses upon the detection of electrons, muons, jets and missing transverse momentum. We describe the design and performance of the major elements of the detector, including the tracking chambers, transition radiation detector, liquid argon calorimetry and muon detection. The associated electronics, triggering systems and data acquisition systems are presented. The global mechanical, high voltage, and experiment monitoring and control systems which support the detector are described. We also discuss the design and implementation of software and software support systems that are specific to DØ.

  20. Noble Gas Detectors

    CERN Document Server

    Aprile, Elena; Bolozdynya, Alexander I; Doke, Tadayoshi

    2006-01-01

    This book discusses the physical properties of noble fluids, operational principles of detectors based on these media, and the best technical solutions to the design of these detectors. Essential attention is given to detector technology: purification methods and monitoring of purity, information readout methods, electronics, detection of hard ultra-violet light emission, selection of materials, cryogenics etc.The book is mostly addressed to physicists and graduate students involved in the preparation of fundamental next generation experiments, nuclear engineers developing instrumentation

  1. ATLAS inner detector performance

    CERN Document Server

    Gadomski, S

    2001-01-01

    The ATLAS Inner Detector consists of three subsystems using different tracking detector technologies: silicon pixels, silicon strips and straw tubes. The combination gives ATLAS a robust, hermetic and efficient tracking system, able to reconstruct tracks at the highest foreseen LHC luminosities. The inner detector provides vertex and momentum measurements, electron identification and some $K/\\pi$ separation. Since last year the beam pipe of ATLAS was changed, causing a redesign of the first tracking layer and a deterioration of the impact parameter resolutions.

  2. The TDCpix readout ASIC: A 75 ps resolution timing front-end for the NA62 Gigatracker hybrid pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Kluge, A., E-mail: alexander.kluge@cern.ch; Aglieri Rinella, G.; Bonacini, S.; Jarron, P.; Kaplon, J.; Morel, M.; Noy, M.; Perktold, L.; Poltorak, K.

    2013-12-21

    The TDCpix is a novel pixel readout ASIC for the NA62 Gigatracker detector. NA62 is a new experiment being installed at the CERN Super Proton Synchrotron. Its Gigatracker detector shall provide on-beam tracking and time stamping of individual particles with a time resolution of 150 ps rms. It will consist of three tracking stations, each with one hybrid pixel sensor. The peak flow of particles crossing the detector modules reaches 1.27 MHz/mm{sup 2} for a total rate of about 0.75 GHz. Ten TDCpix chips will be bump-bonded to every silicon pixel sensor. Each chip shall perform time stamping of 100 M particle hits per second with a detection efficiency above 99% and a timing accuracy better than 200 ps rms for an overall three-station-setup time resolution of better than 150 ps. The TDCpix chip has been designed in a 130 nm CMOS technology. It will feature 45×40 square pixels of 300×300μm{sup 2} and a complex End of Column peripheral region including an array of TDCs based on DLLs, four high speed serializers, a low-jitter PLL, readout and control circuits. This contribution will describe the complete design of the final TDCpix ASIC. It will discuss design choices, the challenges faced and some of the lessons learned. Furthermore, experimental results from the testing of circuit prototypes will be presented. These demonstrate the achievement of key performance figures such as a time resolution of the processing chain of 75 ps rms with a laser sent to the center of the pixel and the capability of time stamping charged particles with an overall resolution below 200 ps rms. -- Highlights: • Feasibility demonstration of a silicon pixel detector with sub-ns time tagging capability. • Demonstrator detector assembly with a time resolution of 75 ps RMS with laser charge injection; 170 ps RMS with particle beam. • Design of trigger-less TDCpix ASIC with 1800 pixels, 720 TDC channels and 4 3.2 Gbit/s serializers.

  3. Evolution of E2 transition strength in deformed hafnium isotopes from new measurements on $^{172}$Hf, $^{174}$Hf, and $^{176}$Hf

    CERN Document Server

    Rudigier, M; Dannhoff, M; Gerst, R-B; Jolie, J; Saed-Samii, N; Stegemann, S; Régis, J-M; Robledo, L M; Rodríguez-Guzmán, R; Blazhev, A; Fransen, Ch; Warr, N; Zell, K O

    2015-01-01

    The available data for E2 transition strengths in the region between neutron-deficient Hf and Pt isotopes are far from complete. More and precise data are needed to enhance the picture of structure evolution in this region and to test state-of-the-art nuclear models. In a simple model, the maximum collectivity is expected at the middle of the major shell. However, for actual nuclei, this picture may no longer be the case, and one should use a more realistic nuclear-structure model. We address this point by studying the spectroscopy of Hf. We remeasure the 2^+_1 half-lives of 172,174,176Hf, for which there is some disagreement in the literature. The main goal is to measure, for the first time, the half-lives of higher-lying states of the rotational band. The new results are compared to a theoretical calculation for absolute transition strengths. The half-lives were measured using \\gamma-\\gamma and conversion-electron-\\gamma delayed coincidences with the fast timing method. For the determination of half-lives i...

  4. LHCb Detector Performance

    CERN Document Server

    AUTHOR|(CDS)2075808; Adeva, Bernardo; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Pessina, Gianluigi; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2015-01-01

    The LHCb detector is a forward spectrometer at the Large Hadron Collider (LHC) at CERN. The experiment is designed for precision measurements of CP violation and rare decays of beauty and charm hadrons. In this paper the performance of the various LHCb sub-detectors and the trigger system are described, using data taken from 2010 to 2012. It is shown that the design criteria of the experiment have been met. The excellent performance of the detector has allowed the LHCb collaboration to publish a wide range of physics results, demonstrating LHCb's unique role, both as a heavy flavour experiment and as a general purpose detector in the forward region.

  5. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS/LHC. The ALFA system is composed by two stations installed in the LHC tunnel 240 m away from each side of the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronic for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  6. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS (A Toroidal LHC Apparatus). The ALFA system is composed by four stations installed in the LHC tunnel 240 m away from the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronics for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  7. Photocapacitive MIS infrared detectors

    Science.gov (United States)

    Sher, A.; Lu, S. S.-M.; Moriarty, J. A.; Crouch, R. K.; Miller, W. E.

    1978-01-01

    A new class of room-temperature infrared detectors has been developed through use of metal-insulator-semiconductor (MIS) or metal-insulator-semiconductor-insulator-metal (MISIM) slabs. The detectors, which have been fabricated from Si, Ge and GaAs, rely for operation on the electrical capacitance variations induced by modulated incident radiation. The peak detectivity for a 1000-A Si MISIM detector is comparable to that of a conventional Si detector functioning in the photovoltaic mode. Optimization of the photocapacitive-mode detection sensitivity is discussed.

  8. Comparative study of atomic-layer-deposited HfO2/Al2O3, Hf0.8Al0.2Ox and Hf0.5Al0.5Ox on N-GaAs

    Science.gov (United States)

    Yu, Xinjiang; Lv, Hongliang; Zhang, Yuming; Zhang, Yimen; Qin, Zaiyang

    2016-11-01

    Interfacial properties of n-GaAs metal-oxide-semiconductor (MOSCAPs) with the gate dielectrics of HfO2/Al2O3, Hf0.8Al0.2Ox and Hf0.5Al0.5Ox are investigated. The results reveal that Hf0.5Al0.5Ox has larger permittivity and lower interface trap density than that of HfO2/Al2O3. In order to explain the result from the physical perspective, the XPS tests of all three samples are performed. It is found that the main reason to form interface trap of three samples treated with 500 °C post-deposition annealing, is attributed to the interfacial component of Ga2O3 and The Hf0.5Al0.5Ox dielectric is beneficial to reducing the formation of Ga2O3.

  9. First 100 ms of HF modification at Tromso, Norway

    Science.gov (United States)

    Djuth, F. T.; Isham, B.; Rietveld, M. T.; Hagfors, T.; La Hoz, C.

    Experiments were performed with the high-power high-frequency HF facility at Troms o Norway to test theoretical predictions for the excitation of ion and Langmuir oscillations in the ionosphere The principal diagnostic of wave-plasma interactions was the VHF radar at the European Incoherent Scatter EISCAT facility High resolution radar techniques were used to monitor the temporal development of the ion and Langmuir oscillations HF pulses 100 ms in duration were periodically transmitted into a smooth background F region plasma Measurements of the radar backscatter spectra show that all key spectral features predicted by strong Langmuir turbulence SLT theory modified Zakharov model are simultaneously present in the plasma and that their evolution is in agreement with theoretical expectations However several new features have been observed that cannot be anticipated by current theory because of limitations in the electric field strength within the simulations The experimental results reinforce the notion that new theoretical developments are needed to accommodate the large HF electric fields produced at Troms o and HAARP Gakona Alaska and to treat the electron acceleration process in a self-consistent fashion The F region response to two HF effective radiated power levels sim 58 MW and sim 125 MW was investigated at Troms o These ERP values include absorptive losses resulting from the sunlit D region In general the results at 58 MW ERP and 125 MW ERP are consistent with many of the SLT

  10. The multilayer Fe/Hf studied with slow positron beam

    Science.gov (United States)

    Murashige, Y.; Tashiro, M.; Nakajyo, T.; Koizumi, T.; Kanazawa, I.; Komori, F.; Ito, Y.

    1997-04-01

    The positron annihilation parameter versus the incident positron energy is measured in the thin Fe films and the Fe/Hf bilayer on silica substrate, by means of the variable energetic slow-positron beam technique. We have analyzed the change in open-volume spaces and vacancy-type defects among the Fe microcrystals in these thin films with the deposition temperature.

  11. A CMOS OTA for HF filters with programmable transfer function

    NARCIS (Netherlands)

    van de Zwan, Eric J.; Klumperink, Eric A.M.; Seevinck, E.; Seevinck, Evert

    1991-01-01

    A CMOS operational transconductance amplifier (OTA) for programmable HF filters is presented. When used in an OTA-C integrator, the unity-gain frequency phase error remains less than 0.3° for frequencies up to more than one tenth of the OTA bandwidth. The OTA has built-in phase compensation, which

  12. Hf isotope evidence for a hidden mantle reservoir

    DEFF Research Database (Denmark)

    Bizzarro, Martin; Simonetti, A.; Stevenson, R.K.

    2002-01-01

    High-precision Hf isotopic analyses and U-Pb ages of carbonatites and kimberlites from Greenland and eastern North America, including Earth's oldest known carbonatite (3 Ga), indicate derivation from an enriched mantle source. This previously unidentified mantle reservoir-marked by an unradiogeni...

  13. Origin of excess 176Hf in meteorites

    DEFF Research Database (Denmark)

    Thrane, Kristine; Connelly, James; Bizzarro, Martin

    2010-01-01

    After considerable controversy regarding the (176)Lu decay constant (lambda(176)Lu), there is now widespread agreement that (1.867 +/- 0.008) x 10(-11) yr(-1) as confirmed by various terrestrial objects and a 4557 Myr meteorite is correct. This leaves the (176)Hf excesses that are correlated with...

  14. Hard x-ray response of pixellated CdZnTe detectors

    Science.gov (United States)

    Abbene, L.; Del Sordo, S.; Caroli, E.; Gerardi, G.; Raso, G.; Caccia, S.; Bertuccio, G.

    2009-06-01

    In recent years, the development of cadmium zinc telluride (CdZnTe) detectors for x-ray and gamma ray spectrometry has grown rapidly. The good room temperature performance and the high spatial resolution of pixellated CdZnTe detectors make them very attractive in space-borne x-ray astronomy, mainly as focal plane detectors for the new generation of hard x-ray focusing telescopes. In this work, we investigated on the spectroscopic performance of two pixellated CdZnTe detectors coupled with a custom low noise and low power readout application specific integrated circuit (ASIC). The detectors (10×10×1 and 10×10×2 mm3 single crystals) have an anode layout based on an array of 256 pixels with a geometric pitch of 0.5 mm. The ASIC, fabricated in 0.8 μm BiCMOS technology, is equipped with eight independent channels (preamplifier and shaper) and characterized by low power consumption (0.5 mW/channel) and low noise (150-500 electrons rms). The spectroscopic results point out the good energy resolution of both detectors at room temperature [5.8% full width at half maximum (FWHM) at 59.5 keV for the 1 mm thick detector; 5.5% FWHM at 59.5 keV for the 2 mm thick detector) and low tailing in the measured spectra, confirming the single charge carrier sensing properties of the CdZnTe detectors equipped with a pixellated anode layout. Temperature measurements show optimum performance of the system (detector and electronics) at T =10 °C and performance degradation at lower temperatures. The detectors and the ASIC were developed by our collaboration as two small focal plane detector prototypes for hard x-ray multilayer telescopes operating in the 20-70 keV energy range.

  15. Forward muon system for the D/Ø detector upgrade

    Science.gov (United States)

    Abramov, V.; Alexeev, G.; Babintsev, V.; Baldin, B.; Butler, J.; Beutel, D.; Bezzubov, V.; Bojko, N.; Burtovoi, V.; Chekulaev, S.; Chi, E.; Denisov, D.; Denisov, S.; Diehl, T.; Dodonov, V.; Dyshkant, A.; Eroshin, O.; Evdokimov, V.; Galyaev, A.; Goncharov, P.; Gornushkin, Yu.; Green, D.; Gurzhiev, S.; Haggerty, H.; Hanlet, P.; Hansen, S.; Hedin, D.; Ito, A.; Johns, K.; Kalinin, A.; Kostritskiy, A.; Kozelov, A.; Kozlovski, E.; Leitner, R.; Lokajíček, M.; Los, S.; Malyshev ∗, V.; Mayorov, A.; Medovikov, V.; Mokhov, N.; Nozdrin, A.; Pisarev, I.; Pospíšil, S.; Raskowski, J.; Sabirov, B.; Šimák, V.; Smith, G.; Stefanik, A.; Stoianova, D.; Suk, M.; Tokmenin, V.; Vaniov, V.; Volkov, A.; Vorobiev, A.; Vrba, V.; Williams, R.; Wood, D.; Yatsunenko, Yu.; Yoffe, F.; Zimin, S.

    1998-12-01

    The design and main parameters of the completly redesigned DØ Forward Angle MUon System (FAMUS: 1.0<| η|<2.0) for the next high luminosity Tevatron Collider run are reported. Results of the studies of trigger scintillation counters based on fast scintillator Bicron 404A and WLS bars SOFZ-105 are presented. We report about results of test beam studies of prototype counters including minimum ionizing particles detection efficiency, time resolution and amplitude response. Radiation ageing of scintillating materials for the doses up to 1 Mrad, phototubes magnetic shielding in the fields of up to 700 G and ageing of phototubes are presented. Mini-Drift Tubes (MDTs) are chosen as FAMUS tracking detectors. The detector is a drift wire chamber with a metallic cathode. The detector operates in proportional mode with a fast freon-methane gas mixture to provide high drift velocity, adequate counting rate and low ageing. A description of the performance of the MDT is given. Studies of two prototypes in test beams were performed at FNAL and JINR. Obtained coordinate accuracy is around 0.5 mm r.m.s. All tests show robustness of MDT as tracking detector of the new muon system for a long period in high DØ background radiation conditions.

  16. Self-diffusion of Er and Hf inpure and HfO/sub 2/-doped polycrystalline Er/sub 2/O/sub 3/. [Hf-175 and Er-169

    Energy Technology Data Exchange (ETDEWEB)

    Scheidecker, R.W.

    1979-01-01

    Using a tracer technique, self-diffusion of Er and Hf was measured over the approximate temperature interval of 1600 to 1970/sup 0/C in pure and HfO/sub 2/-doped polycryatalline Er/sub 2/O/sub 3/. Up to about 10 m/o HfO/sub 2/ dopant level, the Er self-diffusion coefficients followed a relationship based on cation vacancies. Above 10 m/o HfO/sub 2/, deviation from this relationship occurred, apparently due to clustering of cation vacancies and oxygen interstitials around the dopant hafnia ion. The activation energy for the self-diffusion of Er in pure Er/sub 2/O/sub 3/ was 82.2 Kcal/mole and increased with the HfO/sub 2/ dopant level present. Self-diffusion of Hf was measured in pure Er/sub 2/O/sub 3/ having two impurity levels, and a separation of the grain boundary. The volume diffusion of Hf showed both extrinsic and intrinsic behavior with the transition temperature increasing with the impurity level present in Er/sub 2/O/sub 3/. The activation energy for Hf volume diffusion in the intrinsic region was high, i.e. 235 -+ 9.5 Kcal/mole. The grain boundary diffusion was apparently extrinsic over the entire temperature interval Very low Hf self diffusion rates were found in both pure and HfO/sub 2/ doped Er/sub 2/O/sub 3/ compositions. Despite a clustering effect, the HfO/sub 2/ dopant increased the Hf volume diffusion coefficients.

  17. Helium implanted $\\rm\\underline{Al}$Hf as studied by 181Ta TDPAC

    Indian Academy of Sciences (India)

    R Govindaraj; K P Gopinathan; B Viswanathan

    2000-06-01

    Time differential perturbed angular correlation (TDPAC) measurement on $\\rm\\underline{Al}$Hf reference sample has shown that a fraction 0.88 of probe nuclei are defect free and are occupying the substitutional sites in fcc Al matrix, and the remaining are associated with Hf solute clusters. Measurements on helium implanted sample indicate the binding of helium associated defects by Hf solute clusters. Isochronal annealing measurements indicate the dissociation of the helium implantation induced defects from Hf solute clusters for annealing treatments beyond 650 K. On comparison of the present results with that reported in $\\rm\\underline{Cu}$Hf subjected to identical helium implantation, it is inferred that the Hf solute clusters in $\\rm\\underline{Al}$Hf bind less strongly the helium associated defects than in $\\rm\\underline{Cu}$Hf.

  18. Processing and crystallographic structure of non-equilibrium Si-doped HfO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Dong; Fancher, Chris M.; Esteves, Giovanni; Jones, Jacob L., E-mail: jacobjones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Zhao, Lili [School of Information Science and Technology, Northwest University, Xi' an 710127 (China)

    2015-06-28

    Si-doped HfO{sub 2} was confirmed to exist as a non-equilibrium state. The crystallographic structures of Si-doped HfO{sub 2} were studied using high-resolution synchrotron X-ray diffraction and the Rietveld refinement method. Incorporation of Si into HfO{sub 2} and diffusion of Si out of (Hf,Si)O{sub 2} were determined as a function of calcination temperature. Higher thermal energy input at elevated calcination temperatures resulted in the formation of HfSiO{sub 4}, which is the expected major secondary phase in Si-doped HfO{sub 2}. The effect of SiO{sub 2} particle size (nano- and micron-sized) on the formation of Si-doped HfO{sub 2} was also determined. Nano-crystalline SiO{sub 2} was found to incorporate into HfO{sub 2} more readily.

  19. Data of evolutionary structure change: 1CLMA-2HF5A [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1CLMA-2HF5A 1CLM 2HF5 A A LTEEQIAEFKEAFALFDKDGDGTITTKELGTVMRSLGQN...PTEAELQDMINEVDADGNGTIDFPEFLSLMARKMKEQDSEEELIEAFKVFDRDGNGLISAAELRHVMTNLGEKL--TDDEVDEMIREADIDGDGHINYEEFVRMMVS-...ntryChain> 1CLM A 1CLMA LGEKL--TD...ne> 1CLM A 1CLMA

  20. Geographic variations in the PARADIGM-HF heart failure trial.

    Science.gov (United States)

    Kristensen, Søren Lund; Martinez, Felipe; Jhund, Pardeep S; Arango, Juan Luis; Bĕlohlávek, Jan; Boytsov, Sergey; Cabrera, Walter; Gomez, Efrain; Hagège, Albert A; Huang, Jun; Kiatchoosakun, Songsak; Kim, Kee-Sik; Mendoza, Iván; Senni, Michele; Squire, Iain B; Vinereanu, Dragos; Wong, Raymond Ching-Chiew; Gong, Jianjian; Lefkowitz, Martin P; Rizkala, Adel R; Rouleau, Jean L; Shi, Victor C; Solomon, Scott D; Swedberg, Karl; Zile, Michael R; Packer, Milton; McMurray, John J V

    2016-11-01

    The globalization of clinical trials has highlighted geographic variations in patient characteristics, event rates, and treatment effects. We investigated these further in PARADIGM-HF, the largest and most globally representative trial in heart failure (HF) to date. We looked at five regions: North America (NA) 602 (8%), Western Europe (WE) 1680 (20%), Central/Eastern Europe/Russia (CEER) 2762 (33%), Latin America (LA) 1433 (17%), and Asia-Pacific (AP) 1487 (18%). Notable differences included: WE patients (mean age 68 years) and NA (65 years) were older than AP (58 years) and LA (63 years) and had more coronary disease; NA and CEER patients had the worst signs, symptoms, and functional status. North American patients were the most likely to have a defibrillating-device (54 vs. 2% AP) and least likely prescribed a mineralocorticoid receptor antagonist (36 vs. 65% LA). Other evidence-based therapies were used most frequently in NA and WE. Rates of the primary composite outcome of cardiovascular (CV) death or HF hospitalization (per 100 patient-years) varied among regions: NA 13.6 (95% CI 11.7-15.7) WE 9.6 (8.6-10.6), CEER 12.3 (11.4-13.2), LA 11.2 (10.0-12.5), and AP 12.5 (11.3-13.8). After adjustment for prognostic variables, relative to NA, the risk of CV death was higher in LA and AP and the risk of HF hospitalization lower in WE. The benefit of sacubitril/valsartan was consistent across regions. There were many regional differences in PARADIGM-HF, including in age, symptoms, comorbidity, background therapy, and event-rates, although these did not modify the benefit of sacubitril/valsartan. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01035255. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Cardiology.

  1. Mid-Latitude Mobile Wideband HF- NVIS Channel Analysis: Part 1

    Science.gov (United States)

    2017-09-14

    communications (SATCOM) for beyond line-of- sight (LOS) links. However, standard HF systems operating over a 3-kHz bandwidth do not provide sufficient...wideband mid-latitude HF channel soundings and three-dimensional (3-D) ray-tracing simulations to develop a statistical model of a particular nearly...46 5 THE HF-NVIS CHANNEL SOUNDING SYSTEM ...................................................................... 47 5.1 TRANSMIT AND RECEIVE HF

  2. HF Radar observations of the Dardanelles outflow current in North Eastern Aegean using validated WERA HF radar data

    Directory of Open Access Journals (Sweden)

    Z. KOKKINI

    2015-01-01

    Full Text Available A two-site WERA HF radar station was installed in November 2009 at the eastern coast of Lemnos Island in North Aegean Sea, aiming to monitor the surface inflow of Black Sea waters exiting from the Dardanelles Strait, as well as to constitute a coastal management tool for incidents of oil-pollution or save-and-rescue operations. Strong interference by foreign transmissions is a source of noise deteriorating the quality of the backscattered signal, thus significantly reducing the HF radar’s effective data return rate. In order to ameliorate this problem, further quality-control and data gap interpolating procedures have been developed and applied, to be used in addition to the procedures incorporated and used by the manufacturer’s signal processing software. The second-level processing involves traditional despiking in the temporal domain, preceding Empirical Orthogonal Function analysis. The latter is used not only to filter high-frequency noise but also to fill data gaps in time and space. The data reconstruction procedure has been assessed via comparison of (a HF radial with CODE-type drifter radial velocities as well as (b HF-derived virtual drifter tracks with actual drifter tracks. The main circulation features and their variability, as revealed by the reconstructed fields, are presented.

  3. HF Radar observations of the Dardanelles outflow current in North Eastern Aegean using validated WERA HF radar data

    Directory of Open Access Journals (Sweden)

    Z. KOKKINI

    2014-12-01

    Full Text Available A two-site WERA HF radar station was installed in November 2009 at the eastern coast of Lemnos Island in North Aegean Sea, aiming to monitor the surface inflow of Black Sea waters exiting from the Dardanelles Strait, as well as to constitute a coastal management tool for incidents of oil-pollution or save-and-rescue operations. Strong interference by foreign transmissions is a source of noise deteriorating the quality of the backscattered signal, thus significantly reducing the HF radar’s effective data return rate. In order to ameliorate this problem, further quality-control and data gap interpolating procedures have been developed and applied, to be used in addition to the procedures incorporated and used by the manufacturer’s signal processing software. The second-level processing involves traditional despiking in the temporal domain, preceding Empirical Orthogonal Function analysis. The latter is used not only to filter high-frequency noise but also to fill data gaps in time and space. The data reconstruction procedure has been assessed via comparison of (a HF radial with CODE-type drifter radial velocities as well as (b HF-derived virtual drifter tracks with actual drifter tracks. The main circulation features and their variability, as revealed by the reconstructed fields, are presented.

  4. ALICE Photon Multiplicity Detector

    CERN Multimedia

    Nayak, T

    2013-01-01

    Photon Multiplicity Detector (PMD) measures the multiplicity and spatial distribution of photons in the forward region of ALICE on a event-by-event basis. PMD is a pre-shower detector having fine granularity and full azimuthal coverage in the pseudo-rapidity region 2.3 < η < 3.9.

  5. Detector Systems at CLIC

    CERN Document Server

    Simon, Frank

    2011-01-01

    The Compact Linear Collider CLIC is designed to deliver e+e- collisions at a center of mass energy of up to 3 TeV. The detector systems at this collider have to provide highly efficient tracking and excellent jet energy resolution and hermeticity for multi-TeV final states with multiple jets and leptons. In addition, the detector systems have to be capable of distinguishing physics events from large beam-induced background at a crossing frequency of 2 GHz. Like for the detector concepts at the ILC, CLIC detectors are based on event reconstruction using particle flow algorithms. The two detector concepts for the ILC, ILD and SID, were adapted for CLIC using calorimeters with dense absorbers limiting leakage through increased compactness, as well as modified forward and vertex detector geometries and precise time stamping to cope with increased background levels. The overall detector concepts for CLIC are presented, with particular emphasis on the main detector and engineering challenges, such as: the ultra-thi...

  6. ALICE Silicon Strip Detector

    CERN Multimedia

    Nooren, G

    2013-01-01

    The Silicon Strip Detector (SSD) constitutes the two outermost layers of the Inner Tracking System (ITS) of the ALICE Experiment. The SSD plays a crucial role in the tracking of the particles produced in the collisions connecting the tracks from the external detectors (Time Projection Chamber) to the ITS. The SSD also contributes to the particle identification through the measurement of their energy loss.

  7. CMS Detector Posters

    CERN Multimedia

    2016-01-01

    CMS Detector posters (produced in 2000): CMS installation CMS collaboration From the Big Bang to Stars LHC Magnetic Field Magnet System Trackering System Tracker Electronics Calorimetry Eletromagnetic Calorimeter Hadronic Calorimeter Muon System Muon Detectors Trigger and data aquisition (DAQ) ECAL posters (produced in 2010, FR & EN): CMS ECAL CMS ECAL-Supermodule cooling and mechatronics CMS ECAL-Supermodule assembly

  8. Pixel detector readout chip

    CERN Multimedia

    1991-01-01

    Close-up of a pixel detector readout chip. The photograph shows an aera of 1 mm x 2 mm containing 12 separate readout channels. The entire chip contains 1000 readout channels (around 80 000 transistors) covering a sensitive area of 8 mm x 5 mm. The chip has been mounted on a silicon detector to detect high energy particles.

  9. The LDC detector concept

    Indian Academy of Sciences (India)

    Ties Behnke; LDC Concept Group

    2007-11-01

    In preparation of the experimental program at the international linear collider (ILC), the large detector concept (LDC) is being developed. The main points of the LDC are a large volume gaseous tracking system, combined with high precision vertex detector and an extremely granular calorimeter. The main design force behind the LDC is the particle flow concept.

  10. The stability of the bifluoride ion (HF - 2) in the gas phase

    Science.gov (United States)

    Heni, Martin; Illenberger, Eugen

    1985-12-01

    The bifluoride ion (HF-2) has been generated by dissociative electron attachment to trans-1,2-difluorethylene and cis-1,2-difluoroethylene. Evaluation of the energetics for these reactions leads to ΔH0f (HF-2) ≤-6.9 eV and E. A. (HF2)≥4.8 eV.

  11. Photon strength function in the Hf-181 nucleus by method of two-step cascade

    CERN Document Server

    Le Hong Khiem

    2003-01-01

    The applicability of sum-coincidence measurements of two-step cascade gamma ray spectra determining Photon Strength Function (PSF) of Hf-181 induced from Hf-180 (n,2 gamma) Hf-181 reaction is presented. Up to 80% intensity of the primary gamma ray transitions in a wide energy range have been deduced and compared to model calculation.

  12. Suppression Factor of ~(182)W for ~(182)Hf AMS at CIAE

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Suppression factor of 182W is an important index in the measurement of 182Hf with AMS method. This factor is defined as the value of 182W/180Hf in blank samples divised by the measured value of 182 W/180Hf with AMS method. In order to satisfy a

  13. 40 CFR 180.1273 - Beauveria bassiana HF23; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Beauveria bassiana HF23; exemption... FOOD Exemptions From Tolerances § 180.1273 Beauveria bassiana HF23; exemption from the requirement of a tolerance. Residues of Beauveria bassiana HF23 are exempt from the requirement of a tolerance on all...

  14. Introduction to detectors

    CERN Document Server

    Walenta, Albert H

    1995-01-01

    Concepts for momentum measurements,particle identification and energy measurements (calorimeters) as well for imaging applications in medecine, biology and industry (non destructive testing) will be put into relation to the specific detection princip In particular the resolution for position, time, energy and intensity measurement and the efficiency will be discussed. Signal extraction,electronic signal processing and principles of information capture will close the logic circle to the input : the radiation properties.The lecture will provide some sources for data tables and small demonstration computer programs f The basic detector physics as interaction of radiation with matter, information transport via free charges,photons and phonons and the signal formation will be presented in some depth with emphasis on the influence on specific parameters for detector The lecture will cover the most popular detector principles, gas detectors (ion chambers,MPWC's and MSGC's), semiconductor detectors scintillators and ...

  15. Nanomechanical resonance detector

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, Jeffrey C; Zettl, Alexander K

    2013-10-29

    An embodiment of a nanomechanical frequency detector includes a support structure and a plurality of elongated nanostructures coupled to the support structure. Each of the elongated nanostructures has a particular resonant frequency. The plurality of elongated nanostructures has a range of resonant frequencies. An embodiment of a method of identifying an object includes introducing the object to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the object. An embodiment of a method of identifying a molecular species of the present invention includes introducing the molecular species to the nanomechanical resonance detector. A resonant response by at least one of the elongated nanostructures of the nanomechanical resonance detector indicates a vibrational mode of the molecular species.

  16. The PERDaix detector

    Energy Technology Data Exchange (ETDEWEB)

    Bachlechner, Andreas; Beischer, Bastian; Greim, Roman [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany); Kirn, Thomas, E-mail: kirn@physik.rwth-aachen.de [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany); Mai, Carsten; Yearwood, Gregorio Roper; Schael, Stefan; Schug, David; Tholen, Heiner; Wienkenhoever, Jens [I. Physikalisches Institut B, RWTH Aachen University, Aachen 52056 (Germany)

    2012-12-11

    The PERDaix (Proton Electron Radiation Detector Aix-la-Chapelle) detector is designed to measure charged particles in cosmic rays. It can distinguish particle species up to 5 GV rigidity. PERDaix was flown on the BEXUS-11 balloon on 23rd November 2010. The detector has the dimensions of 246 Multiplication-Sign 400 Multiplication-Sign 859 mm{sup 3}, a geometrical acceptance of 32 cm{sup 2}sr, a low weight of 40 kg and a low power consumption of 60 W. The spectrometer consists of a time-of-flight system, a scintillating fiber tracking detector, a permanent magnet and a transition radiation detector. Silicon photomultipliers are used as photodetectors in the time-of-flight and the tracker system.

  17. The PERDaix detector

    Science.gov (United States)

    Bachlechner, Andreas; Beischer, Bastian; Greim, Roman; Kirn, Thomas; Mai, Carsten; Yearwood, Gregorio Roper; Schael, Stefan; Schug, David; Tholen, Heiner; Wienkenhöver, Jens

    2012-12-01

    The PERDaix (Proton Electron Radiation Detector Aix-la-Chapelle) detector is designed to measure charged particles in cosmic rays. It can distinguish particle species up to 5 GV rigidity. PERDaix was flown on the BEXUS-11 balloon on 23rd November 2010. The detector has the dimensions of 246×400×859 mm3, a geometrical acceptance of 32 cm2sr, a low weight of 40 kg and a low power consumption of 60 W. The spectrometer consists of a time-of-flight system, a scintillating fiber tracking detector, a permanent magnet and a transition radiation detector. Silicon photomultipliers are used as photodetectors in the time-of-flight and the tracker system.

  18. ATLAS ITk Pixel detector

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration

    2016-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

  19. Two-dimensional semiconductor HfSe{sub 2} and MoSe{sub 2}/HfSe{sub 2} van der Waals heterostructures by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Aretouli, K. E.; Tsipas, P.; Tsoutsou, D.; Marquez-Velasco, J.; Xenogiannopoulou, E.; Giamini, S. A.; Vassalou, E.; Kelaidis, N.; Dimoulas, A., E-mail: a.dimoulas@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology, National Center for Scientific Research “Demokritos,” 15310, Aghia Paraskevi, Athens (Greece)

    2015-04-06

    Using molecular beam epitaxy, atomically thin 2D semiconductor HfSe{sub 2} and MoSe{sub 2}/HfSe{sub 2} van der Waals heterostructures are grown on AlN(0001)/Si(111) substrates. Details of the electronic band structure of HfSe{sub 2} are imaged by in-situ angle resolved photoelectron spectroscopy indicating a high quality epitaxial layer. High-resolution surface tunneling microscopy supported by first principles calculations provides evidence of an ordered Se adlayer, which may be responsible for a reduction of the measured workfunction of HfSe{sub 2} compared to theoretical predictions. The latter reduction minimizes the workfunction difference between the HfSe{sub 2} and MoSe{sub 2} layers resulting in a small valence band offset of only 0.13 eV at the MoSe{sub 2}/HfSe{sub 2} heterointerface and a weak type II band alignment.

  20. RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS

    Energy Technology Data Exchange (ETDEWEB)

    Baptiste, K.

    2003-05-08

    Several systems rely on the accurate and linear detection of 500 MHz signals, (the fundamental frequency of both the Booster Ring and Storage Ring) over a dynamic range in excess of 25dB. Prior to this upgrade, the detector/monitor was diode based and though this type of detector could handle the dynamic range requirement it could not do so in an accurate and linear manner. In order to meet the requirements (dynamic range greater than or equal to 25dB, accurate and linear to +-0.25dB over the range, and additional circuitry to interface to the legacy control system and interlocks), a new RF Power Detector/Monitor has been developed using two AD8361, Analog Devices Tru RMS Detectors and a fuzzy comparator, which extends the overall detector's range to twice that of the AD8361. Further information is available [www.analogedevices.com/]. Details of the design requirements and the detector/monitor's circuit as well as the performance of the detector will be presented.

  1. The HERMES recoil detector

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Aschenauer, E.C. [DESY, Zeuthen (Germany); Belostotski, S. [B.P. Konstantinov Petersburg Nuclear Physics Insitute, Gatchina (Russian Federation)] [and others; Collaboration: HERMES Recoil Detector Group

    2013-02-15

    For the final running period of HERA, a recoil detector was installed at the HERMES experiment to improve measurements of hard exclusive processes in charged-lepton nucleon scattering. Here, deeply virtual Compton scattering is of particular interest as this process provides constraints on generalised parton distributions that give access to the total angular momenta of quarks within the nucleon. The HERMES recoil detector was designed to improve the selection of exclusive events by a direct measurement of the four-momentum of the recoiling particle. It consisted of three components: two layers of double-sided silicon strip sensors inside the HERA beam vacuum, a two-barrel scintillating fibre tracker, and a photon detector. All sub-detectors were located inside a solenoidal magnetic field with an integrated field strength of 1Tm. The recoil detector was installed in late 2005. After the commissioning of all components was finished in September 2006, it operated stably until the end of data taking at HERA end of June 2007. The present paper gives a brief overview of the physics processes of interest and the general detector design. The recoil detector components, their calibration, the momentum reconstruction of charged particles, and the event selection are described in detail. The paper closes with a summary of the performance of the detection system.

  2. Detectors for Tomorrow's Instruments

    Science.gov (United States)

    Moseley, Harvey

    2009-01-01

    Cryogenically cooled superconducting detectors have become essential tools for a wide range of measurement applications, ranging from quantum limited heterodyne detection in the millimeter range to direct searches for dark matter with superconducting phonon detectors operating at 20 mK. Superconducting detectors have several fundamental and practical advantages which have resulted in their rapid adoption by experimenters. Their excellent performance arises in part from reductions in noise resulting from their low operating temperatures, but unique superconducting properties provide a wide range of mechanisms for detection. For example, the steep dependence of resistance with temperature on the superconductor/normal transition provides a sensitive thermometer for calorimetric and bolometric applications. Parametric changes in the properties of superconducting resonators provides a mechanism for high sensitivity detection of submillimeter photons. From a practical point of view, the use of superconducting detectors has grown rapidly because many of these devices couple well to SQUID amplifiers, which are easily integrated with the detectors. These SQUID-based amplifiers and multiplexers have matured with the detectors; they are convenient to use, and have excellent noise performance. The first generation of fully integrated large scale superconducting detection systems are now being deployed. I will discuss the prospects for a new generation of instruments designed to take full advantage of the revolution in detector technology.

  3. The Belle II Detector

    Science.gov (United States)

    Piilonen, Leo; Belle Collaboration, II

    2017-01-01

    The Belle II detector is now under construction at the KEK laboratory in Japan. This project represents a substantial upgrade of the Belle detector (and the KEKB accelerator). The Belle II experiment will record 50 ab-1 of data, a factor of 50 more than that recorded by Belle. This large data set, combined with the low backgrounds and high trigger efficiencies characteristic of an e+e- experiment, should provide unprecedented sensitivity to new physics signatures in B and D meson decays, and in τ lepton decays. The detector comprises many forefront subsystems. The vertex detector consists of two inner layers of silicon DEPFET pixels and four outer layers of double-sided silicon strips. These layers surround a beryllium beam pipe having a radius of only 10 mm. Outside of the vertex detector is a large-radius, small-cell drift chamber, an ``imaging time-of-propagation'' detector based on Cerenkov radiation for particle identification, and scintillating fibers and resistive plate chambers used to identify muons. The detector will begin commissioning in 2017.

  4. ATLAS Detector Interface Group

    CERN Multimedia

    Mapelli, L

    Originally organised as a sub-system in the DAQ/EF-1 Prototype Project, the Detector Interface Group (DIG) was an information exchange channel between the Detector systems and the Data Acquisition to provide critical detector information for prototype design and detector integration. After the reorganisation of the Trigger/DAQ Project and of Technical Coordination, the necessity to provide an adequate context for integration of detectors with the Trigger and DAQ lead to organisation of the DIG as one of the activities of Technical Coordination. Such an organisation emphasises the ATLAS wide coordination of the Trigger and DAQ exploitation aspects, which go beyond the domain of the Trigger/DAQ project itself. As part of Technical Coordination, the DIG provides the natural environment for the common work of Trigger/DAQ and detector experts. A DIG forum for a wide discussion of all the detector and Trigger/DAQ integration issues. A more restricted DIG group for the practical organisation and implementation o...

  5. Charge storage characteristics and tunneling mechanism of amorphous Ge-doped HfOx films

    Science.gov (United States)

    Qiu, X. Y.; Zhang, S. Y.; Zhang, T.; Wang, R. X.; Li, L. T.; Zhang, Y.; Dai, J. Y.

    2016-09-01

    Amorphous Ge-doped HfOx films have been deposited on p-Si(100) substrates by means of RF magnetron sputtering. Microstructural investigations reveal the partial oxidation of doped Ge atoms in the amorphous HfOx matrix and the existence of HfSiOx interfacial layer. Capacitance-voltage hysteresis of the Ag-/Ge-doped HfOx/Si/Ag memory capacitor exhibits a memory window of 3.15 V which can maintain for >5 × 104 cycles. Current-voltage characteristics reveal that Poole-Frenkel tunneling is responsible for electron transport in the Ge-doped HfOx film.

  6. Detectors - Electronics; Detecteurs - Electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)

    1998-04-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X {yields} e{sup -} converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the {sup 3}He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  7. Prospects for measuring the gravitational free-fall of antihydrogen with emulsion detectors

    CERN Document Server

    Aghion, S.; Amsler, C.; Ariga, A.; Ariga, T.; Belov, A.S.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R.S.; Cabaret, L.; Canali, C.; Caravita, R.; Castelli, F.; Cerchiari, G.; Cialdi, S.; Comparat, D.; Consolati, G.; Derking, J.H.; Di Domizio, S.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Ferragut, R.; Fontana, A.; Genova, P.; Giammarchi, M.; Gligorova, A.; Gninenko, S.N.; Haider, S.; Harasimovicz, J.; Hogan, S.D.; Huse, T.; Jordan, E.; Jørgensen, L.V.; Kaltenbacher, T.; Kawada, J.; Kellerbauer, A.; Kimura, M.; Knecht, A.; Krasnický, D.; Lagomarsino, V.; Magnani, A.; Mariazzi, S.; Matveev, V.A.; Moia, F.; Nebbia, G.; Nédélec, P.; Oberthaler, M.K.; Pacifico, N.; Petráček, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Regenfus, C.; Riccardi, C.; Røhne, O.; Rotondi, A.; Sandaker, H.; Scampoli, P.; Sosa, A.; Storey, J.; Subieta Vasquez, M.A.; Špaček, M.; Testera, G.; Trezzi, D.; Vaccarone, R.; Welsch, C.P.; Zavatarelli, S.

    2013-01-01

    The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. AEgIS will measure the free-fall of an antihydrogen beam traversing a moir\\'e deflectometer. The goal is to determine the gravitational acceleration g for antihydrogen with an initial relative accuracy of 1% by using an emulsion detector combined with a silicon micro-strip detector to measure the time of flight. Nuclear emulsions can measure the annihilation vertex of antihydrogen atoms with a precision of about 1 - 2 microns r.m.s. We present here results for emulsion detectors operated in vacuum using low energy antiprotons from the CERN antiproton decelerator. We compare with Monte Carlo simulations, and discuss the impact on the AEgIS project.

  8. Clinical trials update from the Heart Failure Society of America Meeting 2009: FAST, IMPROVE-HF, COACH galectin-3 substudy, HF-ACTION nuclear substudy, DAD-HF, and MARVEL-1.

    Science.gov (United States)

    Lainscak, Mitja; Coletta, Alison P; Sherwi, Nasser; Cleland, John G F

    2010-02-01

    This article presents findings and a commentary on late-breaking trials presented during the meeting of the Heart Failure Society of America in September 2009. Unpublished reports should be considered as preliminary, since analyses may change in the final publication. The FAST trial showed somewhat better performance of intrathoracic impedance for prediction of deterioration in patients with heart failure (HF) when compared with daily weighing. The IMPROVE-HF study reported the benefits of education on the management of patients with systolic HF. Galectin-3 appeared a useful method for improving risk stratification of patients with chronic HF in a substudy of the COACH trial. A nuclear substudy of the HF-ACTION trial failed to demonstrate that resting myocardial perfusion imaging, a measure of myocardial scar and viability, was clinically useful. A small randomized controlled trial (DAD-HF) suggested that the use of low-dose dopamine in patients with acutely decompensated HF was associated with less deterioration in renal function and less hypokalaemia. The MARVEL-1 trial raises further concerns about the safety of myoblast transplantation in ischaemic HF.

  9. The HOTWAXS detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E.; Derbyshire, G.E. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Diakun, G. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Duxbury, D.M. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)], E-mail: d.m.duxbury@rl.ac.uk; Fairclough, J.P.A. [Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF (United Kingdom); Harvey, I.; Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Lipp, J.D.; Marsh, A.S.; Salisbury, J. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Sankar, G. [Royal Institution of GB, 21 Albemarle Street, London W1S 4BS (United Kingdom); Spill, E.J.; Stephenson, R. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Terrill, N.J. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom)

    2007-10-11

    The development and testing of the HOTWAXS position-sensitive X-ray detector for Synchrotron Radiation Sources is described. Funded from a facility development grant, the aim of the project was to produce a high counting rate, parallax-free photon counting detector to be used in the combined studies of X-ray absorption fine structure and X-ray diffraction (XAFS/XRD), and also in the technique of small angle and wide angle X-ray scattering (SAXS/WAXS). The detector system is described together with results of experiments carried out at the Daresbury Laboratory Synchrotron Radiation Source.

  10. Performance of GLD detector

    Indian Academy of Sciences (India)

    T Yoshioka

    2007-12-01

    Most of the important physics processes to be studied in the international linear collider (ILC) experiment have multi-jets in the final state. In order to achieve better jet energy resolution, the so-called particle flow algorithm (PFA) will be employed and there is a general consensus that PFA derives overall ILC detector design. Four detector concepts for the ILC experiment have been proposed so far in the world; the GLD detector that has a large inner calorimeter radius, which is considered to have an advantage for a PFA, is one of them. In this paper, general scheme and performance of the GLD-PFA will be presented.

  11. Microfluidic Scintillation Detectors

    CERN Multimedia

    Microfluidic scintillation detectors are devices of recent introduction for the detection of high energy particles, developed within the EP-DT group at CERN. Most of the interest for such technology comes from the use of liquid scintillators, which entails the possibility of changing the active material in the detector, leading to an increased radiation resistance. This feature, together with the high spatial resolution and low thickness deriving from the microfabrication techniques used to manufacture such devices, is desirable not only in instrumentation for high energy physics experiments but also in medical detectors such as beam monitors for hadron therapy.

  12. The Silicon Cube detector

    Energy Technology Data Exchange (ETDEWEB)

    Matea, I.; Adimi, N. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France); Blank, B. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France)], E-mail: blank@cenbg.in2p3.fr; Canchel, G.; Giovinazzo, J. [Centre d' Etudes Nucleaires de Bordeaux Gradignan - Universite Bordeaux 1 - UMR 5797, CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175 Gradignan Cedex (France); Borge, M.J.G.; Dominguez-Reyes, R.; Tengblad, O. [Insto. Estructura de la Materia, CSIC, Serrano 113bis, E-28006 Madrid (Spain); Thomas, J.-C. [GANIL, CEA/DSM - CNRS/IN2P3, BP 55027, F-14076 Caen Cedex 5 (France)

    2009-08-21

    A new experimental device, the Silicon Cube detector, consisting of six double-sided silicon strip detectors placed in a compact geometry was developed at CENBG. Having a very good angular coverage and high granularity, it allows simultaneous measurements of energy and angular distributions of charged particles emitted from unbound nuclear states. In addition, large-volume Germanium detectors can be placed close to the collection point of the radioactive species to be studied. The setup is ideally suited for isotope separation on-line (ISOL)-type experiments to study multi-particle emitters and was tested during an experiment at the low-energy beam line of SPIRAL at GANIL.

  13. ATLAS Inner Detector Alignment

    CERN Document Server

    Bocci, A

    2008-01-01

    The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider at CERN. In order to achieve its physics goals, the ATLAS tracking requires that the positions of the silicon detector elements have to be known to a precision better than 10 μm. Several track-based alignment algorithms have been developed for the Inner Detector. An extensive validation has been performed with simulated events and real data coming from the ATLAS. Results from such validation are reported in this paper.

  14. Directional radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  15. The anisotropy of Hf diffusion in {alpha}-Zr

    Energy Technology Data Exchange (ETDEWEB)

    Hood, G.M. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada); Zou, H. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada); Roy, J.A. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada); Schultz, R.J. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada); Matsuura, N. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada); Jackman, J.A. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.]|[Metals Technology Laboratory, CANMET, Ottawa, Ontario (Canada)

    1996-02-01

    Hf diffusion coefficients (D) have been measured ({proportional_to}870-1100 K) in directions parallel (D{sub pa}) and perpendicular (D{sub pe}) to the c-axis of double-faced, single-crystal specimens of both high purity (HP) and nominally pure (NP) {alpha}-Zr. The diffusion profiles were measured by secondary ion mass spectrometry. Hf diffusion in HP {alpha}-Zr is characterised by an activation energy of about 3.0 eV and a pre-exponential factor of about 10{sup -5} m{sup 2}/s. The anisotropy ratio, D{sub pa}/D{sub pe}, is {proportional_to}<1.0 for the HP specimens and mostly >1.0 for the NP specimens. A dependence of D on diffusion time/depth is indicated for some experiments on NP Zr. (orig.).

  16. Photodetachment of HF-in an Electric Field

    Institute of Scientific and Technical Information of China (English)

    WANG De-Hua

    2008-01-01

    @@ Photdetachment of a negative HF-ion in an electric field is studied by using the two-centre model and the closed orbit theory.An analytic formula is presented for the electron flux of HF- in the presence of an electric field.The results show that the oscillation in the electron flux distribution is caused by the rescattering effect of the molecular ion core and the interference betweed the two nuclei.In addition,the interference between the orbits passing through the given spatial point also plays an important role in the electron flux distribution.This study provides a new understanding of the photodetachment of polar molecules in the presence of external field.

  17. Generation of ionospheric ducts by the HAARP HF heater

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, J A; Pradipta, R; Burton, L M; Labno, A; Lee, M C [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Watkins, B J; Fallen, C [University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Kuo, S P [New York University, Brooklyn, NY 11201 (United States); Burke, W J [Air Force Research Laboratory, Hanscom AFB, MA 01731 (United States); Mabius, D; See, B Z, E-mail: mclee@mit.edu [Boston University, Boston, MA 02215 (United States)

    2010-12-15

    We report an investigation of ionospheric ducts having the shape of large plasma sheets, generated by vertically transmitted HAARP HF heater waves in several experiments conducted in Gakona, Alaska. Theory predicts that O-mode heater wave-created ionospheric ducts form parallel-plate waveguides within the meridional plane, and those generated by the X-mode heater waves are orthogonal to the meridional plane. Our theoretical prediction is supported by measurements of ionosonde data (namely ionograms), range-time-intensity (RTI) plots of UHF and HF backscatter radars, as well as magnetometer data analyses. When these plasma sheets experienced ExB drifts, they were intercepted by the HAARP UHF radar and seen as slanted stripes in the RTI plots. This striking feature was also observed in our earlier experiments using the Arecibo UHF radar.

  18. Use of GPS network data for HF Doppler measurements interpretation

    CERN Document Server

    Petrova, Inna R; Latypov, Ruslan R

    2014-01-01

    The method of measurement of Doppler frequency shift of ionospheric signal - HF Doppler technique - is one of well-known and widely used methods of ionosphere research. It allows to research various disturbances in the ionosphere. There are some sources of disturbances in the ionosphere. These are geomagnetic storms, solar flashes, metrological effects, atmospheric waves. This method allows to find out the influence of earthquakes, explosions and other processes on the ionosphere, which occur near to the Earth. HF Doppler technique has the high sensitivity to small frequency variations and the high time resolution, but interpretation of results is difficult. In this work we make an attempt to use GPS data for Doppler measurements interpretation. Modeling of Doppler frequency shift variations with use of TEC allows to separate ionosphere disturbances of medium scale.

  19. Imaging HF-induced large-scale irregularities above HAARP

    Science.gov (United States)

    Djuth, Frank T.; Reinisch, Bodo W.; Kitrosser, David F.; Elder, John H.; Snyder, A. Lee; Sales, Gary S.

    2006-02-01

    The University of Massachusetts-Lowell digisonde is used with the HAARP high-frequency (HF), ionospheric modification facility to obtain radio images of artificially-produced, large-scale, geomagnetic field-aligned irregularities. F region irregularities generated with the HAARP beam pointed in the vertical and geomagnetic field-aligned directions are examined in a smooth background plasma. It is found that limited large-scale irregularity production takes place with vertical transmissions, whereas there is a dramatic increase in the number of source irregularities with the beam pointed parallel to the geomagnetic field. Strong irregularity production appears to be confined to within ~5° of the geomagnetic zenith and does not fill the volume occupied by the HF beam. A similar effect is observed in optical images of artificial airglow.

  20. Performance Analysis of HF Band FB-MC-SS

    Energy Technology Data Exchange (ETDEWEB)

    Hussein Moradi; Stephen Andrew Laraway; Behrouz Farhang-Boroujeny

    2016-01-01

    Abstract—In a recent paper [1] the filter bank multicarrier spread spectrum (FB-MC-SS) waveform was proposed for wideband spread spectrum HF communications. A significant benefit of this waveform is robustness against narrow and partial band interference. Simulation results in [1] demonstrated good performance in a wideband HF channel over a wide range of conditions. In this paper we present a theoretical analysis of the bit error probably for this system. Our analysis tailors the results from [2] where BER performance was analyzed for maximum ration combining systems that accounted for correlation between subcarriers and channel estimation error. Equations are give for BER that closely match the simulated performance in most situations.

  1. Investigation of new type Cu-Hf-Al bulk glassy alloys

    Science.gov (United States)

    Nagy, E.; Rontó, V.; Sólyom, J.; Roósz, A.

    2009-01-01

    In the last years new type Cu-Hf-Al ternary alloys were developed with high glass forming ability and ductility. The addition of Al to Cu-Hf alloys results in improvements in glass formation, thermal stability and mechanical properties of these alloys. We have investigated new Cu-based bulk amorphous alloys in Cu-Hf-Al ternary system. The alloys with Cu49Hf42Al9, Cu46Hf45Al9, Cu50Hf42.5Al7.5 and Cu50Hf45Al5 compositions were prepared by arc melting. The samples were made by centrifugal casting and were investigated by X-ray diffraction method. Thermodynamic properties were examined by differential scanning calorimetry and the structure of the crystallising phases by scanning electron microscopy. The determination of liquidus temperatures of alloys were measured by differential thermal analysis.

  2. First-principles studies of HF molecule adsorption on intrinsic graphene and Al-doped graphene

    Science.gov (United States)

    Sun, Yuanyuan; Chen, Li; Zhang, Feiwu; Li, Daoyong; Pan, Hongzhe; Ye, Jun

    2010-10-01

    In the search for a high-sensitivity sensor for HF gas, the adsorption of HF molecules on both intrinsic and Al-doped graphene sheets is studied by first-principles calculations. We find that the adsorption mechanisms of HF molecules are different for intrinsic graphene and Al-doped graphene. Al-doped graphene has higher adsorption energy and shorter connecting distance to the HF molecule than intrinsic graphene. The calculated net electron transfers, electronic density difference images and densities of states give evidence that the adsorption of HF molecules on Al-doped graphene is by chemisorption, while there is weak physisorption on intrinsic graphene. Therefore, Al-doped graphene can be expected to have applications as a novel sensor for the detection of HF gas. The HF molecules adsorbed on Al-doped graphene material can be reactivated by applying an external electric field of 0.013 a.u.

  3. Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices

    Science.gov (United States)

    Florent, Karine

    The spontaneous polarization in ferroelectrics (FE) makes them particularly attractive for non-volatile memory and logic applications. Non-volatile FRAM memories using perovskite structure materials, such as Lead Zirconate Titanate (PZT) and Strontium Bismuth Tantalate (SBT) have been studied for many years. However, because of their scaling limit and incompatibility with CMOS beyond 130 nm node, floating gate Flash memory technology has been preferred for manufacturing. The recent discovery of ferroelectricity in doped HfO2 in 2011 has opened the door for new ferroelectric based devices compatible with CMOS technology, such as Ferroelectric Field Effect Transistor (FeFET) and Ferroelectric Tunnel Junctions (FTJ). This work began with developing ferroelectric hysteresis characterization capabilities at RIT. Initially reactively sputtered aluminum doped HfO 2 films were investigated. It was observed that the composition control using co-sputtering was not achievable within the existing capabilities. During the course of this study, collaboration was established with the NaMLab group in Germany to investigate Si doped HfO2 deposited by Atomic Layer Deposition (ALD). Metal Ferroelectric Metal (MFM) devices were fabricated using TiN as the top and bottom electrode with Si:HfO2 thickness ranging from 6.4 nm to 22.9 nm. The devices were electrically tested for P-E, C-V and I-V characteristics. Structural characterizations included TEM, EELS, XRR, XRD and XPS/Auger spectroscopy. Higher remanant polarization (Pr) was observed for films of 9.3 nm and 13.1 nm thickness. Thicker film (22.9 nm) showed smaller Pr. Devices with 6.4 nm thick films exhibit tunneling behavior showing a memristor like I-V characteristics. The tunnel current and ferroelectricity showed decrease with cycling indicating a possible change in either the structure or the domain configurations. Theoretical simulations using the improved FE model were carried out to model the ferroelectric behavior of

  4. Centrifugal stretching of 170Hf in the interacting boson model

    Directory of Open Access Journals (Sweden)

    Werner V.

    2014-03-01

    Full Text Available We present the results of a recent experiment to deduce lifetimes of members of the ground state rotational band of 170Hf, which show the effect of centrifugal stretching in this deformed isotope. Results are compared to the geometrical confined beta-soft(CBS rotor model, as well as to the interacting boson model (IBM. Two methods to correct for effects due to the finite valence space within the IBM are proposed.

  5. Electrochemical characterization of cast Ti-Hf binary alloys.

    Science.gov (United States)

    Cai, Z; Koike, M; Sato, H; Brezner, M; Guo, Q; Komatsu, M; Okuno, O; Okabe, T

    2005-05-01

    This study characterized the electrochemical behavior of Ti-Hf binary alloys in a simulated oral environment. Ti-Hf alloys (10, 20, 25, 30, 35 and 40 mass% Hf) were prepared by arc-melting titanium sponge and hafnium sponge. Specimens of each alloy (n = 4) were prepared using a dental titanium casting system with a MgO-based investment. Specimens were inspected with X-ray radiography to ensure minimal internal porosity. Castings (n = 4) made from pure titanium and commercially pure titanium were used as controls. The ground flat surface (10 mm x 10 mm) on each specimen where approximately 30 microm was removed was used for the characterization. Sixteen-hour open-circuit potential (OCP) measurement, linear polarization and potentiodynamic cathodic polarization were performed sequentially in aerated (air + 10% CO2) MTZ synthetic saliva at 37 degrees C. Potentiodynamic anodic polarization was conducted in the same medium but deaerated (N2 + 10% CO2) 2 h before and during testing. Polarization resistance (R(P)) and Tafel slopes were determined, as were corrosion current density (I(CORR)) and passive current density (I(PASS)). Results were subjected to nonparametric statistical analysis (alpha = 0.05). The OCP stabilized (mean values -229 mV to -470 mV vs. SCE) for all specimens after the 16-h immersion. Similar passivation was observed for all the metals on their anodic polarization diagrams. The Kruskal-Wallis test showed significant differences in OCP among the test groups (p = 0.006). No significant differences were found in R(P), I(CORR) or I(PASS) among all the metals (p>0.3). Results indicate that the electrochemical behavior of the Ti-Hf alloys examined resembles that of pure titanium.

  6. Self-healing structural properties of thermoplastics in HF field

    Directory of Open Access Journals (Sweden)

    N. G. Filippenko

    2014-01-01

    Full Text Available The article concerns one of the possible ways for safe operation of polymer products with initiating a process of their self-healing. This is especially true for products from polymer materials, used in hard-to-reach areas and units of machines and mechanisms. In this regard, the aim of this study was to develop techniques for a self-healing process of the mechanical properties of products from polymer materials.To achieve this goal, the author has solved problems to define a complex method of HF self-healing of polymer material: damage detection in products from polymer materials, determination of signal initiating the recovery process, determining the efficiency of material regeneration. The present study uses proposed and developed by the author methods for the determination of necessary and sufficient indicators of the strength characteristics of products under realmeteorological and climatic conditions of their operation.To determine the practical results of the developed algorithm for self-healing the polymer products in the HF field, a series of experimental studies has been conducted to regenerate the polyamide cage fatigue destruction of the rolling stock axle equipment of Russian Railways JSC.The obtained results of the strength characteristics of the material under investigation prove the self-healing process of polymer materials in HF field.According to research results, the conclusion is drawn that it is required to provide a technological HF self-healing process of products from polymer materials. The created algorithm of regeneration enables a new approach to study the effects of electromagnetic fields on polymer and polymer-based composite materials when solving the practical tasks to improve the quality of repairing parts from thermoplastics.

  7. Hf--Co--B alloys as permanent magnet materials

    Science.gov (United States)

    McGuire, Michael Alan; Rios, Orlando; Ghimire, Nirmal Jeevi

    2017-01-24

    An alloy composition is composed essentially of Hf.sub.2-XZr.sub.XCo.sub.11B.sub.Y, wherein 0B.sub.Y, wherein 0.ltoreq.X<2 and 0

  8. Ionizing wave via high-power HF acceleration

    CERN Document Server

    Mishin, Evgeny

    2010-01-01

    Recent ionospheric modification experiments with the 3.6 MW transmitter at the High Frequency Active Auroral Research Program (HAARP) facility in Alaska led to discovery of artificial ionization descending from the nominal interaction altitude in the background F-region ionosphere by ~60 km. This paper presents a physical model of an ionizing wavefront created by suprathermal electrons accelerated by the HF-excited plasma turbulence.

  9. Study on Preparation of 182Hf AMS Standards

    Institute of Scientific and Technical Information of China (English)

    YINXin-yi; JIANGShan; HEMing; ZHANGChun-hua; ZHANGSheng-dong

    2003-01-01

    The neutron-rich isotope 182Hf with its half-life of (9±2)×106 a produced by neutron activation can be used to determine the neutron flux of some places, in order to study the transport of radioactive nuclides and the safe disposal of nuclear waste. AMS is a kind of relative measurement method with high sensitivity (10-15), it requires corresponding standard samples.

  10. Ionizing wave via high-power HF acceleration

    OpenAIRE

    Mishin, Evgeny; Pedersen, Todd

    2010-01-01

    Recent ionospheric modification experiments with the 3.6 MW transmitter at the High Frequency Active Auroral Research Program (HAARP) facility in Alaska led to discovery of artificial ionization descending from the nominal interaction altitude in the background F-region ionosphere by ~60 km. This paper presents a physical model of an ionizing wavefront created by suprathermal electrons accelerated by the HF-excited plasma turbulence.

  11. On the Onset of HF-Induced Airglow at HAARP

    Science.gov (United States)

    2007-11-02

    AFRL-VS-HA-TR-2005-1061 JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109, A02305, doi:10.1029/2003JA010205, 2004 On the onset of HF-induced airglow at HAARP ...line) during the February 2002 campaign at the High Frequency Active Auroral Research Program ( HAARP ) heating facility are analyzed. We find that... HAARP , J. Geophys. Res., 109, A02305, doi: 10.1029/2003JA010205. 1. Introduction known as the parametric decay (PDI) or oscillating two- [2] A

  12. HF Over-the-Horizon Radar System Performance Analysis

    Science.gov (United States)

    2007-09-01

    target detection technique and radar equations are applied. Chapter V uses PROPLAB model simulation to bring in the principle of raytracing and... RADAR SYSTEM PERFORMANCE ANALYSIS by Bin-Yi Liu September 2007 Thesis Co-Advisors: Phillip E. Pace Jeffrey B. Knorr THIS PAGE...Thesis 4. TITLE AND SUBTITLE HF Over-the-Horizon Radar System Performance Analysis 6. AUTHOR(S) Bin-Yi Liu 5. FUNDING NUMBERS 7. PERFORMING

  13. Wideband high frequency (HF) skywave channel parameters from narrowband measurements

    Science.gov (United States)

    Hausman, Cynthia L.; Uffelman, Donald R.; Walton, Thomas L.

    The HF wideband channel allow the use of spread-spectrum techniques to provide covert communications with low probability of intercept (LPI) and antijam protection. The objective of this work is to determine the extent to which oblique narrowband channel measurements can be used to infer effects in the wideband skywave channel. If oblique narrowband channel measurements can be used as a basis for developing wideband channel models, a large number of existing narrowband measurements can be made available for this task.

  14. Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications

    Science.gov (United States)

    Kühn, S.; Bibinov, N.; Gesche, R.; Awakowicz, P.

    2010-01-01

    A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O3, correspondingly, are generated.

  15. HPLC determination of ibuprofen, diclofenac and salicylic acid using hollow fiber-based liquid phase microextraction (HF-LPME).

    Science.gov (United States)

    Ramos Payán, María; Bello López, Miguel Angel; Fernández-Torres, Rut; Pérez Bernal, Juan Luis; Callejón Mochón, Manuel

    2009-10-27

    This paper describes an extraction method using a polypropylene membrane supporting dihexyl ether (three-phase hollow fiber-based liquid phase microextraction (HF-LPME)) for the analysis of several pharmaceuticals (salicylic acid (SAC), ibuprofen (IBU) and diclofenac (DIC)) followed by a HPLC determination using a monolithic silica type HPLC column, that allows lower retention times than the usual packed columns with adequate resolution. Detection was realized by means of a coupled in series diode array (DAD) and fluorescence (FLD) detectors. HF-LPME is a relatively new technique employed in analytical chemistry for sample pretreatment which offers more selectivity and sensitivity than any traditional extraction technique. Detection limits by DAD are 12, 53 and 40 ng mL(-1) for salicylic acid, diclofenac and ibuprofen, respectively and by FLD 7 and 2 ng mL(-1) for salicylic acid, and ibuprofen. The method has been successfully applied to their direct determination in human urine and the results obtained demonstrated that could be also applied to the determination of the corresponding metabolites.

  16. Comparison of the Multi-anode PMTs with the old HF PMTs by Studying the Collision Data

    CERN Document Server

    Oz, Yavuz

    2013-01-01

    The Hadron Forward (HF) calorimeter of the CMS detector improves jet detection and missing transverse energy resolution in the high pseudorapidity range. HF employs photomultiplier tubes (PMT) that measure the Cerenkov light emitted by shower products in quartz fibers. Stray muons that hit a PMT window create high energy events that are difficult to reject. To alleviate this problem, the PMTs installed in the CMS will be replaced with those of better performance. From among various candidate PMTs, quad-anode Hamamatsu R7600U-200-M4 were chosen to replace the single-anode Hamamatsu R7525HA PMTs. The quad-anode PMTs offer the possibility to reject window events at the hardware level; muons hitting the window are localized to a single anode, while real events illuminate all four anodes. In 2011, eight such PMTs were installed in the readout boxes corresponding to the coordinates $i\\phi=67$, $i\\eta=29,30,31,32$, which get very few hits on account of their location. The purpose of this thesis is to compare the res...

  17. Detection of HCl and HF by TTFMS and WMS.

    Science.gov (United States)

    De Luca, Anna Chiara; Pesce, Giuseppe; Rusciano, Giulia; Sasso, Antonio

    2006-04-01

    In this work we discuss on a compact spectrometer based on DFB diode lasers for detection of chloridric and fluoridric acids. HCl and HF concentrations are determined through optical absorption of the P(4) line (lambda=1.7 microm) and the R(3) line (lambda=1.3 microm), respectively. Both lines belong to first overtone vibrational bands and their line strengths are 7.8 x 10(-21)cm/molecule for HCl and 2.8 x 10(-20)cm/molecule for HF. We chose these lines for their relative high intensities and because they are quite far from water vapour lines which represent the main interfering gas for trace-gases analysis. To detect these species we used two different high frequency modulation techniques: two-tone frequency modulation spectroscopy (f(1)=800 MHz and f(2)=804 MHz) was used for HCl while for HF we followed a simpler approach based on wavelength modulation spectroscopy (f=600 kHz). We demonstrate that the two techniques provide comparable detection limit of about 80 ppbV at atmospheric pressure. Positive testing of our spectrometer makes it suitable for in situ measurements of exhaust gases coming from waste incinerators.

  18. Multiple excitation modes in 163Hf

    DEFF Research Database (Denmark)

    Yadav, Rachita; Ma, J.C.; Marsh, J.C.

    2014-01-01

    Excited states of Hf163 were populated using the Zr94(Ge74,5n) reaction and the decay γ rays were measured with the Gammasphere spectrometer. Two previously known bands were extended to higher spins, and nine new bands were identified. In addition to bands associated with three- and five-quasipar......Excited states of Hf163 were populated using the Zr94(Ge74,5n) reaction and the decay γ rays were measured with the Gammasphere spectrometer. Two previously known bands were extended to higher spins, and nine new bands were identified. In addition to bands associated with three- and five......-quasiparticle configurations, two γ−vibrational bands coupled to the i13/2 excitation were also observed. The lowest level of a newly identified, negative-parity band is proposed to be the ground state of the nucleus. A systematic delay of the high-spin proton crossing frequency with increasing quadrupole deformation from Hf...

  19. Electronic structures and properties of Ti, Zr and Hf metals

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The electronic structures of pure Ti, Zr and Hf metals with hcp structure were determined by one-atom (OA) theory. According to the electronic structures of these metals,their potential curves, cohesive energies, lattice constants, elasticities and the temperature dependence of linear thermal expansion coefficients were calculated. The electronic structures and characteristic properties of these metals with bcc and fcc structures and liquids were also studied. The results show that the electronic structures of Ti, Zr and Hf metals are respectively [Ar](3dn)0.481 0(3dc)2.085 7(4sc)1.000 0(4sf)0.433 3, [Kr](4dn)0.396 8(4dc)2.142 8(5sc)1.262 0(5sf)0.198 4, [Xe](5dn)0.368 0(5dc)2.041 4(6sc)1.406 6(6sf)0.184 0. It is explained why the pure Ti, Zr and Hf metals with hcp and bcc structures can exist naturally, while those with fcc structure can not.

  20. Lu-Hf and Sm-Nd garnet geochronology

    DEFF Research Database (Denmark)

    Smit, Matthijs Arjen; Scherer, Erik E.; Mezger, Klaus

    2013-01-01

    are similar among grains having radii larger than 1.3 mm (weighted mean: 2714±6 Ma2714±6 Ma; 2 s.d.) and up to 20 Myr younger for finer fractions. In contrast, Sm–Nd dates are equal to or younger than the 2641–2637 Ma age of peak metamorphism. The roles of concurrently digested inclusions and core–rim Lu......To investigate the systematics of the 176Lu–176Hf and 147Sm–143Nd garnet chronometers, we performed REE and isotope analyses on garnet crystals of different size (0.55–3.1 mm radius) from a single granulite specimen (Archean Pikwitonei Granulite Domain, Manitoba, Canada). The Lu–Hf dates....../Sm fractionation are quantitatively evaluated and excluded as causes for the observed age heterogeneity. Instead, the isotope dates are interpreted to reflect partial loss of radiogenic 176Hf and 143Nd, and are used to constrain the systematics of the garnet chronometers at high temperature. The data constrain...

  1. TID measurement using oblique transmissions of HF pulses

    Science.gov (United States)

    Galkin, Ivan; Reinisch, Bodo; Huang, Xueqin; Paznukhov, Vadym; Hamel, Ryan; Kozlov, Alexander; Belehaki, Anna

    2017-04-01

    The Traveling Ionospheric Disturbance (TID), a wave-like signature of moving plasma density modulation in the ionosphere, is widely acknowledged for its utility in backtracking the anomalous events responsible for the TID generation, and as a major inconvenience to high-frequency (HF) operational systems because of its deleterious impact on the accuracy of navigation and geolocation. The pilot project "Net-TIDE" for the real-time detection and evaluation of TIDs began its operation in 2016 based on the remote-sensing data from synchronized, network-coordinated HF sounding between pairs of DPS4D ionosondes at five participating observatories in Europe. Measurement of all signal properties (Doppler frequency, angle of arrival, and time-of-flight from transmitter to receiver) proved to be instrumental in detecting the TID and deducing the TID parameters: amplitude, wavelength, phase velocity, and direction of propagation. Processing of the measured HF signal data required a specialized signal processing technique that is capable of consistently extracting different signals that have propagated along different ionospheric paths. The multi-path signal environment proved to be the greatest challenge for the reliable TID specification by Net-TIDE, demanding the development of an intelligent system for "signal tracking". The intelligent system is based on a neural network model of a pre-attentive vision capable of extracting continuous signal tracks from the multi-path signal ensemble. Specific examples of the Net-TIDE algorithm suite operation and its suitability for a fully automated TID warning service are discussed.

  2. Novel Photo-Detectors and Photo-Detector Systems

    OpenAIRE

    Danilov, M.

    2008-01-01

    Recent developments in photo-detectors and photo-detector systems are reviewed. The main emphasis is made on Silicon Photo-Multipliers (SiPM) - novel and very attractive photo-detectors. Their main features are described. Properties of detectors manufactured by different producers are compared. Different applications are discussed including calorimeters, muon detection, tracking, Cherenkov light detection, and time of flight measurements.

  3. The scissors mode and other magnetic and electric dipole excitations in the transitional nuclei {sup 178,180}Hf

    Energy Technology Data Exchange (ETDEWEB)

    Pietralla, N. [Koeln Univ. (Germany). Inst. fuer Kernphysik; Beck, O. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Besserer, J. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Brentano, P. von [Koeln Univ. (Germany). Inst. fuer Kernphysik; Eckert, T. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Fischer, R. [Koeln Univ. (Germany). Inst. fuer Kernphysik; Fransen, C. [Koeln Univ. (Germany). Inst. fuer Kernphysik; Herzberg, R.-D. [Koeln Univ. (Germany). Inst. fuer Kernphysik; Jaeger, D. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Jolos, R.V. [Koeln Univ. (Germany). Inst. fuer Kernphysik]|[Bogoliubov Theoretical Laboratory, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Kneissl, U. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Krischok, B. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Margraf, J. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Maser, H. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Nord, A. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Pitz, H.H. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Rittner, M. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Schiller, A. [Institut fuer Strahlenphysik, Universitaet Stuttgart, 70569 Stuttgart (Germany); Zilges, A. [Koeln Univ. (Germany). Inst. fuer Kernphysik]|[WNSL, Yale University, P.O. Box 208124, New Haven, CT 06520-8124 (United States)

    1997-05-26

    Photon scattering experiments have been performed on the heavy deformed nuclei {sup 178,180}Hf using an E{sub {gamma}}<4 MeV bremsstrahlung beam as a continuous energy photon source. Numerous dipole excitations have been identified from the spectra of high-resolution Ge {gamma} detectors. Spins, K quantum numbers, dipole excitation strengths, and level widths, have been extracted from the scattering cross sections. From the measured level widths lifetimes of 67 levels can be deduced. The excitation strength of the scissor mode is discussed and extends the systematics from the neighboring rare earth nuclei. Besides the {Delta}K=1 excitations other dipole excitations have been observed that are distinguished from the scissor mode states by their different decay behavior. (orig.).

  4. Measurement of the transverse four-dimensional beam rms-emittance of an intense uranium beam at 11.4 MeV/u

    Science.gov (United States)

    Xiao, C.; Groening, L.; Gerhard, P.; Maier, M.; Mickat, S.; Vormann, H.

    2016-06-01

    Knowledge of the transverse four-dimensional beam rms-parameters is essential for applications that involve lattice elements that couple the two transverse degrees of freedom (planes). Usually pepper-pots are used for measuring these beam parameters. However, for ions their application is limited to energies below 150 keV/u. This contribution is on measurements of the full transverse four-dimensional second-moments beam matrix of high intensity uranium ions at an energy of 11.4 MeV/u. The combination of skew quadrupoles with a slit/grid emittance measurement device has been successfully applied.

  5. High-spin positive-parity states in 179Hf studied by the 180Hf(τ, α) 179Hf reaction AT 32 MeV

    Science.gov (United States)

    Thorsteinsen, T. F.; Løvhøiden, G.; Vaagen, J. S.; Bjørnberg, A.; Burke, D. G.

    1981-06-01

    Full angular distributions are presented for states populated in the reaction 180Hf(τ, α) 179Hf at 32 MeV beam energy. Positive-parity states associated with the i {13}/{2} unique parity intruder orbital are given special attention. Thus, angular distributions for the five first members of the [624 {9}/{2}] groundstate sequence are given, as well as for a number of more highly excited states, some being new assignments. The distribution of l = 6 transfer strength is quite characteristic, two {13}/{2}+ states being substantially more populated than the rest. The characteristic features of the data are explained by a quasiparticle-rotor calculation employing deformed Woods-Saxon orbitals, but only if the hexadecapole shape parameter of the nuclear potential is β 4 ˜ -0.08. The often anomalous differential cross sections for I π ≠ {13}/{2}+ band members are well accounted for by a rotor model CCBA calculation employing transfer form factors extracted from the orbitals of the deformed Woods-Saxon field, and including non-adiabatic Coriolis mixing effects.

  6. Mechanical Design and Development of TES Bolometer Detector Arrays for the Advanced ACTPol Experiment

    Science.gov (United States)

    Ward, Jonathan T.; Austermann, Jason; Beall, James A.; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark J.; Duff, Shannon M.; Gallardo, Patricio M.; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; Hilton, Gene; Hubmayr, Johannes; Khavari, Niloufar; Klein, Jeffrey; Koopman, Brian J.; Li, Dale; McMahon, Jeffrey; Mumby, Grace; Nati, Federico; Wollack, Edward J.

    2016-01-01

    The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling 5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150 mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline pro le leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at the detector array stack assemblies. This experiment will also make use of extensive hardware and software previously developed for ACT, which will be modi ed to incorporate the new AdvACT instruments. Therefore, we discuss the integration of all AdvACT arrays with pre-existing ACTPol infrastructure.

  7. Hf isotopic compositions of the standard zircons for U-Pb dating

    Institute of Scientific and Technical Information of China (English)

    XU Ping; WU Fuyuan; XIE Liewen; YANG Yueheng

    2004-01-01

    Using the newly published Yb isotopic abundances and the mass bias relationship between Yb and Hf, we carried out an analysis of Hf isotopes in the standard zircon 91500 by means of 193 nm laser attached to Neptune multi-collector ICP-MS (LA-MC-ICPMS). The obtained Hf isotopic data, in either in situ or line scan modes, are not only identical for different spot sizes, but also are consistent with previously published results obtained on TIMS or other MC-ICPMS machines within errors. This indicates that it is possible to obtain reliable 176Hf/177Hf isotopic ratios for zircon in either in situ or line scan conditions on LA-MC-ICPMS machine, and the applied procedures in our study for elemental interfering correction are appropriate for the purpose of acquiring satisfactory accuracy for Hf isotope analyses. The Hf isotopic compositions of four zircon standards in high spatial resolution U-Pb dating, 91500, CZ3,CN92-1 and TEMORA, are measured, respectively. The obtained 176Hf/177Hf ratios are 0.282316+4 (n = 34, 2σ) for 91500, 0.281704±6 (n = 16, 2σ) for CZ3, 0.282200±6 (n = 20,2σ-) for CN92-1 and 0.282684±14 (n = 24, 2σ) for TEMORA,respectively, with 176Lu/177Hf ratios of ~0.00031, 0.000036,0.00083 and 0.00127. Zircons 91500 and CZ3 show narrower variations in 176Hf/177Hf and 176Lu/177Hf ratios than those of zircons CN92-1 and TEMORA, and thus are appropriate standards for the Hf isotope analysis.

  8. Infrared Detectors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The end goal of this project is to develop proof-of-concept infrared detectors which can be integrated in future infrared instruments engaged in remote...

  9. ALICE Forward Multiplicity Detector

    CERN Multimedia

    Christensen, C

    2013-01-01

    The Forward Multiplicity Detector (FMD) extends the coverage for multiplicity of charge particles into the forward regions - giving ALICE the widest coverage of the 4 LHC experiments for these measurements.

  10. OPAL detector electromagnetic calorimeter

    CERN Multimedia

    1988-01-01

    Half of the electromagnetic calorimeter of the OPAL detector is seen in this photo. This calorimeter consists of 4720 blocks of lead glass. It was used to detect and measure the energy of photons, electrons and positrons by absorbing them.

  11. The LUX Prototype Detector

    CERN Document Server

    Akerib, D S; Bedikian, S; Bernstein, A; Bolozdynya, A; Bradley, A; Cahn, S; Carr, D; Chapman, J J; Clark, K; Classen, T; Curioni, A; Dahl, C E; Dazeley, S; deViveiros, L; Dragowsky, M; Druszkiewicz, E; Fiorucci, S; Gaitskell, R J; Hall, C; Faham, C; Holbrook, B; Kastens, L; Kazkaz, K; Kwong, J; Lander, R; Leonard, D; Malling, D; Mannino, R; McKinsey, D N; Mei, D; Mock, J; Morii, M; Nikkel, J; Phelps, P; Shutt, T; Skulski, W; Sorensen, P; Spaans, J; Steigler, T; Svoboda, R; Sweany, M; Thomson, J; Tripathi, M; Walsh, N; Webb, R; White, J; Wolfs, F L H; Woods, M; Zhang, C

    2012-01-01

    The LUX (Large Underground Xenon) detector is a two-phase xenon Time Projection Chamber (TPC) designed to search for WIMP-nucleon dark matter interactions. As with all noble element detectors, continuous purification of the detector medium is essential to produce a large ($>$1ms) electron lifetime; this is necessary for efficient measurement of the electron signal which in turn is essential for achieving robust discrimination of signal from background events. In this paper we describe the development of a novel purification system deployed in a prototype detector. The results from the operation of this prototype indicated heat exchange with an efficiency above 94% up to a flow rate of 42 slpm, allowing for an electron drift length greater than 1 meter to be achieved in approximately two days and sustained for the duration of the testing period.

  12. The CLIC Detector Concept

    CERN Document Server

    Pitters, Florian Michael

    2016-01-01

    CLIC is a concept for a future linear collider that would provide e+e- collisions at up to 3 TeV. The physics aims require a detector system with excellent jet energy and track momentum resolution, highly efficient flavour-tagging and lepton identification capabilities, full geometrical coverage extending to low polar angles and timing information in the order of nanoseconds to reject beam-induced background. To deal with those requirements, an extensive R&D programme is in place to overcome current technological limits. The CLIC detector concept includes a low-mass all-silicon vertex and tracking detector system and fine-grained calorimeters designed for particle flow analysis techniques, surrounded by a 4 T solenoid magnet. An overview of the requirements and design optimisations for the CLIC detector concept is presented.

  13. Hybrid photon detectors

    CERN Document Server

    D'Ambrosio, C

    2003-01-01

    Hybrid photon detectors detect light via vacuum photocathodes and accelerate the emitted photoelectrons by an electric field towards inversely polarized silicon anodes, where they are absorbed, thus producing electron-hole pairs. These, in turn, are collected and generate electronic signals on their ohmic contacts. This review first describes the characteristic properties of the main components of hybrid photon detectors: light entrance windows, photocathodes, and silicon anodes. Then, essential relations describing the trajectories of photoelectrons in electric and magnetic fields and their backscattering from the silicon anodes are derived. Depending on their anode configurations, three families of hybrid photon detectors are presented: hybrid photomultiplier tubes with single anodes for photon counting with high sensitivity and for gamma spectroscopy; multi-anode photon detector tubes with anodes subdivided into square or hexagonal pads for position-sensitive photon detection; imaging silicon pixel array t...

  14. GRAVITY detector systems

    Science.gov (United States)

    Mehrgan, Leander H.; Finger, Gert; Eisenhauer, Frank; Panduro, Johana

    2016-08-01

    GRAVITY is a second generation instrument for the VLT Interferometer, designed for high-precision narrow-angle astrometry and phase-referenced interferometric imaging in the K-band. It will combine the AO corrected beams of the four VLT telescopes. In total, the GRAVITY instrument uses five eAPD detectors four for the infrared wavefront sensors of each telescope and one for the fringe tracker. In addition two Hawaii2RG arrays are installed, one for the acquisition camera and one for the spectrometer. The SAPHIRA eAPD array is a newly developed near-infrared detector with sub-electron noise performance at frame rates > 1Kfps. For all seven detectors the ESO common controller, NGC, is used. This paper presents an overview and comparison of GRAVITY detector systems and their final performances at the telescope

  15. Pocked surface neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas (Whitmore Lake, MI); Klann, Raymond (Bolingbrook, IL)

    2003-04-08

    The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

  16. Europe plans megaton detector

    CERN Multimedia

    Cartlidge, Edwin

    2004-01-01

    A group of French and Italian particle physicists hopes to carry on the long tradition of building large underground detectors by constructing a device deep under the Alps containing a million tonnes of extremely pure water.

  17. The pixelated detector

    CERN Multimedia

    Sutton, C

    1990-01-01

    "Collecting data as patterns of light or subatomic particles is vitally important in all the sciences. The new generation of solid-state detectors called pixel devices could transform experimental research at all levels" (4 pages).

  18. Improved CO [lidar detector

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, P.L.; Busch, G.E.; Thompson, D.C.; Remelius, D.K.; Wells, F.D.

    1999-07-18

    A high sensitivity, CO{sub 2} lidar detector, based on recent advances in ultra-low noise, readout integrated circuits (ROIC), is being developed. This detector will combine a high speed, low noise focal plane array (FPA) with a dispersive grating spectrometer. The spectrometer will filter the large background flux, thereby reducing the limiting background photon shot noise. In order to achieve the desired low noise levels, the HgCdTe FPA will be cooled to {approximately}50K. High speed, short pulse operation of the lidar system should enable the detector to operate with the order of a few noise electrons in the combined detector/ ROIC output. Current receiver design concepts will be presented, along with their expected noise performance.

  19. Detector Control System for the ATLAS Forward Proton detector

    CERN Document Server

    Czekierda, Sabina; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) is a forward detector using a Roman Pot technique, recently installed in the LHC tunnel. It is aiming at registering protons that were diffractively or electromagnetically scattered in soft and hard processes. Infrastructure of the detector consists of hardware placed both in the tunnel and in the control room USA15 (about 330 meters from the Roman Pots). AFP detector, like the other detectors of the ATLAS experiment, uses the Detector Control System (DCS) to supervise the detector and to ensure its safe and coherent operation, since the incorrect detector performance may influence the physics results. The DCS continuously monitors the detector parameters, subset of which is stored in data bases. Crucial parameters are guarded by alarm system. A detector representation as a hierarchical tree-like structure of well-defined subsystems built with the use of the Finite State Machine (FSM) toolkit allows for overall detector operation and visualization. Every node in the hierarchy is...

  20. The AMANDA Neutrino Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wischnewski, R.; Andres, E.; Askebjer, P.; Barwick, S.; Bay, R.; Bergstroem, L.; Biron, A.; Booth, J.; Botner, O.; Bouchta, A.; Carius, S.; Carlson, M.; Chinowsky, W.; Chirkin, D.; Cowen, D.; Costa, C.; Dalberg, E.; Deyoung, T.; Edsjo, J.; Ekstroem, P.; Goobar, A.; Gray, L.; Hallgren, A.; Halzen, F.; Hardtke, R.; He, Y.; Hill, G.; Hulth, P.; Hundertmark, S.; Jacobsen, J.; Kandhadai, V.; Karle, A.; Kim, J.; Leich, H.; Leuthold, M.; Lindahl, P.; Liss, T.; Liubarsky, I.; Loaiza, P.; LOwder, D.; Marciniewski, P.; Miller, T.; Miocinovic, P.; Mock, P.; Morse, R.; Newcomer, M.; Niessen, P.; Nygren, D.; Perez de los Heros, C.; Porrata, R.; Price, P.; Przybylski, G.; Rhode, W.; Richter, S.; Rodriguez, J.; Romenesko, P.; Ross, D.; Rubinstein, H.; Schmidt, T.; Schneider, E.; Schwarz, R.; Schwendicke, U.; Smoot, G.; Solarz, M.; Sorin, V.; Spiering, C.; Steffen, P.; Stokstad, R.; Streicher, O.; Thollander, L.; Thon, T.; Tilav, S.; Walck, C.; Wiebusch, C.; Woschnagg, K.; Wu, W.; Yodh, G.; Young, S

    1999-03-01

    The first stage of the AMANDA High Energy Neutrino Detector at the South Pole, the 302 PMT array AMANDA-B with an expected effective area for TeV neutrinos of {approx} 10{sup 4} m{sup 2}, has been taking data since 1997. Progress with calibration, investigation of ice properties, as well as muon and neutrino data analysis are described. The next stage 20-string detector AMANDA-II with {approx}800 PMTs will be completed in spring 2000.

  1. Fiber optic detector

    Energy Technology Data Exchange (ETDEWEB)

    Partin, J.K.; Ward, T.E.; Grey, A.E.

    1990-12-31

    This invention is comprised of a portable fiber optic detector that senses the presence of specific target chemicals by exchanging the target chemical for a fluorescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

  2. Phi factory detector requirements

    Energy Technology Data Exchange (ETDEWEB)

    Arisaka, K.; Atac, M.; Berg, R.; Buchanan, C.; Calvette, M.; Khazin, B.; Kinoshita, K.; Muller, T.; Ohshima, T.; Olsen, S.; Park, J.; Santoni, C.; Shirai, J.; Solodov, E.; Thompson, J.; Triggiani, G.; Ueno, K.; Yamamoto, H.; Detector and Simulation Working Group

    1991-08-01

    We identify the experimental problems and the conditions required for successful phi-factory operation, and show the range of detector parameters which, in conjunction with different machine designs, may meet these conditions. We started by considering, comparing and criticizing the Italian and Novosibirsk designs. With this discussion as a background, we defined the apparent experimental problems and detector constraints. In this article we summarize our understanding. (orig./HSI).

  3. Electrical characteristics of MOS capacitor with HfTiON gate dielectric and HfTiSiON interlayer

    Institute of Scientific and Technical Information of China (English)

    Chen Wei-Bing; Xu Jing-Ping; Lai Pui-To; Li Yan-Ping; Xu Sheng-Guo; Chan Chu-Lok

    2006-01-01

    The paper reports that HfTiO dielectric is deposited by reactive co-sputtering of Hf and Ti targets in an Ar/O2 ambience, followed by an annealing in different gas ambiences of N2, NO and NHa at 600°C for 2 min. Capacitance-voltage and gate-leakage properties are characterized and compared. The results indicate that the NO-annealed sample exhibits the lowest interface-state and dielectric-charge densities and best device reliability. This is attributed to the fact that nitridation can create strong Si≡N bonds to passivate dangling Si bonds and replace strained Si- O bonds, thus the sample forms a hardened dielectric/Si interface with high reliability.

  4. Modelling semiconductor pixel detectors

    CERN Document Server

    Mathieson, K

    2001-01-01

    expected after 200 ps in most cases. The effect of reducing the charge carrier lifetime and examining the charge collection efficiency has been utilised to explore how these detectors would respond in a harsh radiation environment. It is predicted that over critical carrier lifetimes (10 ps to 0.1 ns) an improvement of 40 % over conventional detectors can be expected. This also has positive implications for fabricating detectors, in this geometry, from materials which might otherwise be considered substandard. An analysis of charge transport in CdZnTe pixel detectors has been performed. The analysis starts with simulation studies into the formation of contacts and their influence on the internal electric field of planar detectors. The models include a number of well known defect states and these are balanced to give an agreement with a typical experimental I-V curve. The charge transport study extends to the development of a method for studying the effect of charge sharing in highly pixellated detectors. The ...

  5. Gamma ray detector modules

    Science.gov (United States)

    Capote, M. Albert (Inventor); Lenos, Howard A. (Inventor)

    2009-01-01

    A radiation detector assembly has a semiconductor detector array substrate of CdZnTe or CdTe, having a plurality of detector cell pads on a first surface thereof, the pads having a contact metallization and a solder barrier metallization. An interposer card has planar dimensions no larger than planar dimensions of the semiconductor detector array substrate, a plurality of interconnect pads on a first surface thereof, at least one readout semiconductor chip and at least one connector on a second surface thereof, each having planar dimensions no larger than the planar dimensions of the interposer card. Solder columns extend from contacts on the interposer first surface to the plurality of pads on the semiconductor detector array substrate first surface, the solder columns having at least one solder having a melting point or liquidus less than 120 degrees C. An encapsulant is disposed between the interposer circuit card first surface and the semiconductor detector array substrate first surface, encapsulating the solder columns, the encapsulant curing at a temperature no greater than 120 degrees C.

  6. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to

  7. ATLAS Inner Detector (Pixel Detector and Silicon Tracker)

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    To raise awareness of the basic functions of the Pixel Detector and Silicon Tracker in the ATLAS detector on the LHC at CERN. This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the detector, seeing critical pieces of the detector and hearing short explanations of how each works.

  8. The magnetic properties of $^{\\rm 177}$Hf and $^{\\rm 180}$Hf in the strong coupling deformed model

    CERN Document Server

    Muto, S; Bingham, C R; Stone, J R; Walker, P M; Audi, G; Gaulard, C; Köster, U; Nikolov, J; Nishimura, K; Ohtsubo, T; Podolyak, Z; Risegari, L; Simpson, G S; Veskovic, M; Walters, W B

    2014-01-01

    This paper reports NMR measurements of the magnetic dipole moments of two high-K isomers, the 37/2$^-$, 51.4 m, 2740 keV state in $^{\\rm 177}$Hf and the 8$^-$, 5.5 h, 1142 keV state in $^{\\rm 180}$Hf by the method of on-line nuclear orientation. Also included are results on the angular distributions of gamma transitions in the decay of the $^{\\rm 177}$Hf isotope. These yield high precision E2/M1 multipole mixing ratios for transitions in bands built on the 23/2$^+$, 1.1 s, isomer at 1315 keV and on the 9/2$^+$, 0.663 ns, isomer at 321 keV. The new results are discussed in the light of the recently reported finding of systematic dependence of the behavior of the g$_{\\rm R}$ parameter upon the quasi-proton and quasi-neutron make up of high-K isomeric states in this region.

  9. Detectors on the drawing board

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Linear collider detector developers inside and outside CERN are tackling the next generation of detector technology. While their focus has centred on high-energy linear collider detectors, their innovative concepts and designs will be applicable to any future detector.   A simulated event display in one of the new generation detectors. “While the LHC experiments remain the pinnacle of detector technology, you may be surprised to realise that the design and expertise behind them is well over 10 years old,” says Lucie Linssen, CERN’s Linear Collider Detector (LCD) project manager whose group is pushing the envelope of detector design. “The next generation of detectors will have to surpass the achievements of the LHC experiments. It’s not an easy task but, by observing detectors currently in operation and exploiting a decade’s worth of technological advancements, we’ve made meaningful progress.” The LCD team is curr...

  10. Polarity reversion of the operation mode of HfO2-based resistive random access memory devices by inserting Hf metal layer.

    Science.gov (United States)

    Peng, Ching-Shiang; Chang, Wen-Yuan; Lin, Ming-Ho; Chen, Wei-Su; Chen, Frederick; Tsai, Ming-Jinn

    2013-03-01

    The reversion of polarity within bipolar resistive switching operation occurs in Pt/HfO2/TiN and Pt/Hf/HfO2/TiN resistive random access memory devices. This reversion of voltage polarity is the result of interface generation which induces a conduction mechanism transformation from Poole-Frenkel emission to space charge limited current mechanism. To prove the reversion of polarity, this study uses curve fitting of I-V relations to verify the conduction mechanism theoretically and physical analysis to verify the oxygen ion distribution practically. The proposed Pt/Hf/HfO2/TiN devices exhibit good resistive switching characteristics, such as good uniformity, low voltage operation, robust endurance (10(3) dc sweep), and long retention (3 x 10(4) s at 85 degrees C).

  11. Vertically oriented few-layered HfS2 nanosheets: growth mechanism and optical properties

    Science.gov (United States)

    Zheng, Binjie; Chen, Yuanfu; Wang, Zegao; Qi, Fei; Huang, Zhishuo; Hao, Xin; Li, Pingjian; Zhang, Wanli; Li, Yanrong

    2016-09-01

    For the first time, large-area, vertically oriented few-layered hafnium disulfide (V-{{{HfS}}}2) nanosheets have been grown by chemical vapor deposition. The individual {{{HfS}}}2 nanosheets are well [001] oriented, with highly crystalline quality. Far different from conventional van der Waals epitaxial growth mechanism for two-dimensional transition metal dichalcogenides, a novel dangling-bond-assisted self-seeding growth mechanism is proposed to describe the growth of V-{{{HfS}}}2 nanosheets: difficult migration of {{{HfS}}}2 adatoms on substrate surface results in {{{HfS}}}2 seeds growing perpendicularly to the substrate; V-{{{HfS}}}2 nanosheets inherit the growth direction of {{{HfS}}}2 seeds; V-{{{HfS}}}2 nanosheets further expand in the in-plane direction with time evolution. Moreover, the V-{{{HfS}}}2 nanosheets show strong and broadened photons absorption from near infrared to ultraviolet; the V-{{{HfS}}}2-based photodetector exhibits an ultrafast photoresponse time of 24 ms, and a high photosensitivity ca. 103 for 405 nm laser.

  12. Empirical Study of the Multiaxial, Thermomechanical Behavior of NiTiHf Shape Memory Alloys

    Science.gov (United States)

    Shukla, Dhwanil; Noebe, Ronald D.; Stebner Aaron P.

    2013-01-01

    An empirical study was conducted to characterize the multiaxial, thermomechanical responses of new high temperature NiTiHf alloys. The experimentation included loading thin walled tube Ni(sub 50.3)Ti(sub 29.7)Hf(sub 20) alloy samples along both proportional and nonproportional axial-torsion paths at different temperatures while measuring surface strains using stereo digital image correlation. A Ni(sub 50.3)Ti(sub 33.7)Hf(sub 16) alloy was also studied in tension and compression to document the effect of slightly depleting the Hf content on the constitutive responses of NiTiHf alloys. Samples of both alloys were made from nearly texture free polycrystalline material processed by hot extrusion. Analysis of the data shows that very small changes in composition significantly alter NiTiHf alloy properties, as the austenite finish (Af) temperature of the 16-at Hf alloy was found to be approximately 60 C less than the 20-at Hf alloy (approximately 120 C vs. 180 C). In addition, the 16-at Hf alloy exhibited smaller compressive transformation strains (2 vs. 2.5 percent). Multi-axial characterization of the 20-at % Hf alloy showed that while the random polycrystal transformation strains in tension (4 percent) and compression (2.5 percent) are modest in comparison with binary NiTi (6 percent, 4 percent), the torsion performance is superior (7 vs. 4 shear strain width to the pseudoelastic plateau).

  13. Effects of HfB2 and HfN Additions on the Microstructures and Mechanical Properties of TiB2-Based Ceramic Tool Materials

    Directory of Open Access Journals (Sweden)

    Jing An

    2017-04-01

    Full Text Available The effects of HfB2 and HfN additions on the microstructures and mechanical properties of TiB2-based ceramic tool materials were investigated. The results showed that the HfB2 additive not only can inhibit the TiB2 grain growth but can also change the morphology of some TiB2 grains from bigger polygons to smaller polygons or longer ovals that are advantageous for forming a relatively fine microstructure, and that the HfN additive had a tendency toward agglomeration. The improvement of flexural strength and Vickers hardness of the TiB2-HfB2 ceramics was due to the relatively fine microstructure; the decrease of fracture toughness was ascribed to the formation of a weaker grain boundary strength due to the brittle rim phase and the poor wettability between HfB2 and Ni. The decrease of the flexural strength and Vickers hardness of the TiB2-HfN ceramics was due to the increase of defects such as TiB2 coarse grains and HfN agglomeration; the enhancement of fracture toughness was mainly attributed to the decrease of the pore number and the increase of the rim phase and TiB2 coarse grains. The toughening mechanisms of TiB2-HfB2 ceramics mainly included crack bridging and transgranular fracture, while the toughening mechanisms of TiB2-HfN ceramics mainly included crack deflection, crack bridging, transgranular fracture, and the core-rim structure.

  14. Crystallography of the NiHfSi Phase in a NiAl (0.5 Hf) Single-Crystal Alloy

    Science.gov (United States)

    Garg, A.; Noebe, R. D.; Darolia, R.

    1996-01-01

    Small additions of Hf to conventionally processed NiAl single crystals result in the precipitation of a high density of cuboidal G-phase along with a newly identified silicide phase. Both of these phases form in the presence of Si which is not an intentional alloying addition but is a contaminant resulting from contact with the ceramic shell molds during directional solidification of the single-crystal ingots. The morphology, crystal structure and Orientation Relationship (OR) of the silicide phase in a NiAl (0.5 at.%Hf) single-crystal alloy have been determined using transmission electron microscopy, electron microdiffraction and energy dispersive X-ray spectroscopy. Qualitative elemental analysis and indexing of the electron microdiffraction patterns from the new phase indicate that it is an orthorhombic NiHfSi phase with unit cell parameters, a = 0.639 nm, b = 0.389 nm and c = 0.72 nm, and space group Pnma. The NiHfSi phase forms as thin rectangular plates on NiAl/111/ planes with an OR that is given by NiHfSi(100))(parallel) NiAl(111) and NiHfSi zone axes(010) (parallel) NiAl zone axes (101). Twelve variants of the NiHfSi phase were observed in the alloy and the number of variants and rectangular morphology of NiHfSi plates are consistent with symmetry requirements. Quenching experiments indicate that nucleation of the NiHfSi phase in NiAI(Hf) alloys is aided by the formation of NiAl group of zone axes (111) vacancy loops that form on the NiAl /111/ planes.

  15. An ab initio study of the C2H2-HF, C2H(CH3)-HF and C2(CH3)2-HF hydrogen-bonded complexes.

    Science.gov (United States)

    Ramos, Mozart N; Lopes, Kelson C; Silva, Washington L V; Tavares, Alessandra M; Castriani, Fátima A; do Monte, Silmar A; Ventura, Elizete; Araújo, Regiane C M U

    2006-02-01

    MP2/6-31++G** and B3LYP/6-31++G** ab initio molecular orbital calculations have been performed in order to obtain molecular geometries, binding energies and vibrational properties of the C2H2-HF, C2H(CH3)-HF and C2(CH3)2-HF H-bonded complexes. As expected, the more pronounced effects on the structural properties of the isolated molecules due to complexation was verified for the C[triple bond]C and H-F bond lengths, which are directly involved in the H-bond formation. These bond distances increased after complexation. BSSE uncorrected B3LYP binding energies are always lower than the corresponding MP2 values. However, the opposite trend has been verified after BSSE correction by the counterpoise method since it is much lower at B3LYP than at MP2 level. The binding energies for these complexes as well as for the HF acid submolecule modes (the HF stretching and vibrational frequency modes) showed an increasing hydrogen-bonding strength with increasing methyl substitution. The splitting in the HF in-plane and out-of-plane bending modes reflects the anisotropy in the hydrogen-bonding interaction with the pi system of the C[triple bond]C bond. The H-F stretching frequency is shifted downward after complexation and it increases with the methyl substitution. The IR intensities of the HF acid submolecule fundamentals are adequately interpreted through the atomic polar tensor of the hydrogen atom using the charge-charge flux-overlap model. The skeletal stretching modes of the Alkyne submolecule are decreased in the complex. The new vibrational modes arising from complexation show several interesting features.

  16. The ZEUS microvertex detector

    CERN Document Server

    Garfagnini, A

    1999-01-01

    A new vertex detector for the ZEUS experiment at HERA will be installed during the 1999-2000 shutdown, for the high-luminosity runs of HERA. It will allow to reconstruct secondary vertex tracks, coming from the decay of long-lived particles with a lifetime of about 10 sup - sup 1 sup 2 s, and improve the global momentum resolution of the tracking system. The interaction region will be surrounded with single-sided silicon strip detectors, with capacitive charge division: three double layers in the central region (600 detectors), and 4 'wheels' in the forward region (112 silicon planes). Due to the high number of readout channels, 512 readout strips per silicon plane in the barrel region and 480 in the forward part, and the large coverage of the vertex detector (almost 1 m long), the front-end electronics has to be placed on top of the detectors and has to be radiation tolerant since doses up to 2 kGy are expected near the interaction region. The HELIX chip has been chosen as analog chip with a low-noise, charg...

  17. Nonequilibrium superconducting detectors

    Science.gov (United States)

    Cristiano, R.; Ejrnaes, M.; Esposito, E.; Lisitskyi, M. P.; Nappi, C.; Pagano, S.; Perez de Lara, D.

    2006-03-01

    Nonequilibrium superconducting detectors exploit the early stages of the energy down cascade which occur after the absorption of radiation. They operate on a short temporal scale ranging from few microseconds down to tens of picoseconds. In such a way they provide fast counting capability, high time discrimination and also, for some devices, energy sensitivity. Nonequilibrium superconducting detectors are developed for their use both in basic science and in practical applications for detection of single photons or single ionized macromolecules. In this paper we consider two devices: distributed readout imaging detectors (DROIDs) based on superconducting tunnel junctions (STJs), which are typically used for high-speed energy spectroscopy applications, and hot-electron superconductive detectors (HESDs), which are typically used as fast counters and time discriminators. Implementation of the DROID geometry to use a single superconductor is discussed. Progress in the fabrication technology of NbN nanostructured HESDs is presented. The two detectors share the high sensitivity that makes them able to efficiently detect even single photons down to infrared energy.

  18. Nonequilibrium superconducting detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cristiano, R [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Ejrnaes, M [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); INFN Sezione di Napoli, 80126 Naples (Italy); Esposito, E [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Lisitskyi, M P [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Nappi, C [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Pagano, S [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy); Dipartimento di Fisica, Universita di Salerno, 84081 Baronissi (Saudi Arabia) (Italy); Perez de Lara, D [CNR-Istituto di Cibernetica E. Caianiello, 80078 Pozzuoli (Namibia) (Italy)

    2006-03-15

    Nonequilibrium superconducting detectors exploit the early stages of the energy down cascade which occur after the absorption of radiation. They operate on a short temporal scale ranging from few microseconds down to tens of picoseconds. In such a way they provide fast counting capability, high time discrimination and also, for some devices, energy sensitivity. Nonequilibrium superconducting detectors are developed for their use both in basic science and in practical applications for detection of single photons or single ionized macromolecules. In this paper we consider two devices: distributed readout imaging detectors (DROIDs) based on superconducting tunnel junctions (STJs), which are typically used for high-speed energy spectroscopy applications, and hot-electron superconductive detectors (HESDs), which are typically used as fast counters and time discriminators. Implementation of the DROID geometry to use a single superconductor is discussed. Progress in the fabrication technology of NbN nanostructured HESDs is presented. The two detectors share the high sensitivity that makes them able to efficiently detect even single photons down to infrared energy.

  19. Detectors in Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Blaj, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carini, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carron, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Haller, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hart, P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hasi, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Herrmann, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Kenney, C. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Segal, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Tomada, A. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-06

    Free Electron Lasers opened a new window on imaging the motion of atoms and molecules. At SLAC, FEL experiments are performed at LCLS using 120Hz pulses with 1012 - 1013 photons in 10 femtoseconds (billions of times brighter than the most powerful synchrotrons). This extreme detection environment raises unique challenges, from obvious to surprising. Radiation damage is a constant threat due to accidental exposure to insufficiently attenuated beam, focused beam and formation of ice crystals reflecting the beam onto the detector. Often high power optical lasers are also used (e.g., 25TW), increasing the risk of damage or impeding data acquisition through electromagnetic pulses (EMP). The sample can contaminate the detector surface or even produce shrapnel damage. Some experiments require ultra high vacuum (UHV) with strict design, surface contamination and cooling requirements - also for detectors. The setup is often changed between or during experiments with short turnaround times, risking mechanical and ESD damage, requiring work planning, training of operators and sometimes continuous participation of the LCLS Detector Group in the experiments. The detectors used most often at LCLS are CSPAD cameras for hard x-rays and pnCCDs for soft x-rays.

  20. Coalescence of silver clusters by immersion in diluted HF solution

    Energy Technology Data Exchange (ETDEWEB)

    Milazzo, R. G.; Mio, A. M.; D’Arrigo, G.; Spinella, C. [CNR-IMM Institute for Microelectronics and Microsystems, I-95121 Catania (Italy); Grimaldi, M. G. [Department of Physics and Astronomy, Università di Catania, I-95123 Catania (Italy); MATIS IMM-CNR, I-95123 Catania (Italy); Rimini, E. [CNR-IMM Institute for Microelectronics and Microsystems, I-95121 Catania (Italy); Department of Physics and Astronomy, Università di Catania, I-95123 Catania (Italy)

    2015-07-14

    The galvanic displacement deposition of silver on H-terminated Si (100) in the time scale of seconds is instantaneous and characterized by a cluster density of 10{sup 11}-10{sup 12} cm{sup −2}. The amount of deposited Ag follows a t{sup 1/2} dependence in agreement with a Cottrell diffusion limited mechanism. At the same time, during the deposition, the cluster density reduces by a factor 5. This behavior is in contrast with the assumption of immobile clusters. We show in the present work that coalescence and aggregation occur also in the samples immersed in the diluted hydrofluoric acid (HF) solution without the presence of Ag{sup +}. Clusters agglomerate according to a process of dynamic coalescence, typical of colloids, followed by atomic redistribution at the contact regions with the generation of multiple internal twins and stacking-faults. The normalized size distributions in terms of r/r{sub mean} follow also the prediction of the Smoluchowski ripening mechanism. No variation of the cluster density occurs for samples immersed in pure H{sub 2}O solution. The different behavior might be associated to the strong attraction of clusters to oxide-terminated Si surface in presence of water. The silver clusters are instead weakly bound to hydrophobic H-terminated Si in presence of HF. HF causes then the detachment of clusters and a random movement on the silicon surface with mobility of about 10{sup −13} cm{sup 2}/s. Attractive interaction (probably van der Waals) among particles promotes coarsening.

  1. Strong photoluminescence of the porous silicon with HfO2-filled microcavities

    Science.gov (United States)

    Jiang, Ran; Wu, Zhengran; Du, Xianghao; Han, Zuyin; Sun, Weideng

    2015-06-01

    Greatly enhanced blue emission was observed at room temperature in the single-crystal silicon with HfO2 filled into its microcavities. The broad blue band light was emitted from both the HfO2 dielectric and the porous Si. The ferroelectricity of HfO2 enhances the blue emission from Si by its filling into the microcaivities. At the same time, HfO2 contributes to the light emission for the transitions of the defect levels for oxygen vacancy. The observation of greatly enhanced blue light emission of the porous Si filled with HfO2 dielectric is remarkable as both HfO2 and Si are highly compatible with Si-based electronic industry.

  2. Ozone Treatment Improved the Resistive Switching Uniformity of HfAlO2 Based RRAM Devices

    Directory of Open Access Journals (Sweden)

    Lifeng Liu

    2015-01-01

    Full Text Available HfAlO2 based resistive random access memory (RRAM devices were fabricated using atomic layer deposition by modulating deposition cycles for HfO2 and Al2O3. Effect of ozone treatment on the resistive switching uniformity of HfAlO2 based RRAM devices was investigated. Compared to the as-fabricated devices, the resistive switching uniformity of HfAlO2 based RRAM devices with the ozone treatment is significantly improved. The uniformity improvement of HfAlO2 based RRAM devices is related to changes in compositional and structural properties of the HfAlO2 resistive switching film with the ozone treatment.

  3. Medium-Range Order Structure and Fragility of Superheated Melts of Amorphous CuHf Alloys

    Institute of Scientific and Technical Information of China (English)

    BIAN Xiu-Fang; SUN Bao-An; HU Li-Na

    2006-01-01

    @@ The structural factors of amorphous CuHf alloys at different temperatures are determined by using a high temperature x-ray diffractometer. It is found that not only the short-range order structure but also the medium-range order structure exists in amorphous CuHf alloys. The dynamic viscosities of CuHf alloy melts are measured by a torsional oscillation viscometer. The fragility of superheated melts of CuHf alloys is calculated based on the viscosity data. The experimental results show that the glass-forming ability of the CuHf alloys is closely related to the fragility of their superheated melt. The relationship between the medium-range order structures and the fragility of superheated melts has also been established in amorphous CuHf alloys. In contrast to the fragility of supercooled liquids, the fragility of superheated liquids promises a better approach to reflecting the dynamics of glass forming liquids.

  4. OPERA: Electronic Detector

    CERN Document Server

    Jollet, C

    2010-01-01

    OPERA is an hybrid detector for the ni-tau appearance search in a direct way, and the Electronic Detectors (ED) have the crucial role of triggerring for the neutrino events and of localizing such an interaction inside the target. Another very important task of the ED is to identify the muon since only a correct matching of such a track with a track in the emulsion connected to the vertex of the event allows to reduce the charm background to the desired level. The ED, fully working since 2006, consist of a target tracker (scintillator strips) and a spectrometer (RPC and drift tubes). The different sub-detectors are de- scribed in the poster, as well as their performance both on Monte Carlo (MC) and real data.

  5. Transition Radiation Detectors

    CERN Document Server

    Andronic, A

    2012-01-01

    We review the basic features of transition radiation and how they are used for the design of modern Transition Radiation Detectors (TRD). The discussion will include the various realizations of radiators as well as a discussion of the detection media and aspects of detector construction. With regard to particle identification we assess the different methods for efficient discrimination of different particles and outline the methods for the quantification of this property. Since a number of comprehensive reviews already exist, we predominantly focus on the detectors currently operated at the LHC. To a lesser extent we also cover some other TRDs, which are planned or are currently being operated in balloon or space-borne astro-particle physics experiments.

  6. The LHCb Detector Upgrade

    CERN Document Server

    Schindler, H

    2013-01-01

    The LHCb collaboration presented a Letter of Intent (LOI) to the LHCC in March 2011 for a major upgrading of the detector during Long Shutdown 2 (2018) and intends to collect a data sample of 50/fb in the LHC and High-Luminosity-LHC eras. The aim is to operate the experiment at an instantaneous luminosity 2.5 times above the present operational luminosity, which has already been pushed to twice the design value. Reading out the detector at 40MHz allows to increase the trigger efficiencies especially for the hadronic decay modes. The physics case and the strategy for the upgrade have been endorsed by the LHCC. This paper presents briefly the physics motivations for the LHCb upgrade and the proposed changes to the detector and trigger.

  7. Cryogenic Tracking Detectors

    CERN Multimedia

    Luukka, P R; Tuominen, E M; Mikuz, M

    2002-01-01

    The recent advances in Si and diamond detector technology give hope of a simple solution to the radiation hardness problem for vertex trackers at the LHC. In particular, we have recently demonstrated that operating a heavily irradiated Si detector at liquid nitrogen (LN$_2$) temperature results in significant recovery of Charge Collection Efficiency (CCE). Among other potential benefits of operation at cryogenic temperatures are the use of large low-resistivity wafers, simple processing, higher and faster electrical signal because of higher mobility and drift velocity of carriers, and lower noise of the readout circuit. A substantial reduction in sensor cost could result The first goal of the approved extension of the RD39 program is to demonstrate that irradiation at low temperature in situ during operation does not affect the results obtained so far by cooling detectors which were irradiated at room temperature. In particular we shall concentrate on processes and materials that could significantly reduce th...

  8. The AFP Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

  9. Ionosphere research with a HF/MF cubesat radio instrument

    Science.gov (United States)

    Kallio, Esa; Aikio, Anita; Alho, Markku; Fontell, Mathias; Harri, Ari-Matti; Kauristie, Kirsti; Kestilä, Antti; Koskimaa, Petri; Mäkelä, Jakke; Mäkelä, Miika; Turunen, Esa; Vanhamäki, Heikki; Verronen, Pekka

    2017-04-01

    New technology provides new possibilities to study geospace and 3D ionosphere by using spacecraft and computer simulations. A type of nanosatellites, CubeSats, provide a cost effective possibility to provide in-situ measurements in the ionosphere. Moreover, combined CubeSat observations with ground-based observations gives a new view on auroras and associated electromagnetic phenomena. Especially joint and active CubeSat - ground based observation campaigns enable the possibility of studying the 3D structure of the ionosphere. Furthermore using several CubeSats to form satellite constellations enables much higher temporal resolution. At the same time, increasing computation capacity has made it possible to perform simulations where properties of the ionosphere, such as propagation of the electromagnetic waves in the medium frequency, MF (0.3-3 MHz) and high frequency, HF (3-30 MHz), ranges is based on a 3D ionospheric model and on first-principles modelling. Electromagnetic waves at those frequencies are strongly affected by ionospheric electrons and, consequently, those frequencies can be used for studying the plasma. On the other hand, even if the ionosphere originally enables long-range telecommunication at MF and HF frequencies, the frequent occurrence of spatiotemporal variations in the ionosphere disturbs communication channels, especially at high latitudes. Therefore, study of the MF and HF waves in the ionosphere has both a strong science and technology interests. We introduce recently developed simulation models as well as measuring principles and techniques to investigate the arctic ionosphere by a polar orbiting CubeSat whose novel AM radio instrument measures HF and MF waves. The cubesat, which contains also a white light aurora camera, is planned to be launched in late 2017 (http://www.suomi100satelliitti.fi/eng). The new models are (1) a 3D ray tracing model and (2) a 3D full kinetic electromagnetic simulation. We also introduce how combining of the

  10. HF beacon network for ionospheric specification in Peru

    Science.gov (United States)

    Hysell, D. L.; Milla, M. A.; Vierinen, J.

    2016-12-01

    A growing network of HF beacon transmitters and receivers is being deployed in Peru for specifying the F region ionosphere regionally. The effort is motivated by ionospheric disturbances associated with equatorial spread F (ESF), especially disturbances arising under inauspicious ESF conditions. The beacons use dual frequencies (2.72 and 3.64 MHz). They incorporate PRN coding to afford group-delay measurements. Scatered power, Doppler shift, bearing, and polarization are also measured. An algorithm for inverting the beacon data combined with electron density profiles from Jicamarca is described. Data and representative solutions from recent campaigns will be reviewed.

  11. A SYNCHRONIZATION ALGORITHM FOR HF (HIGH FREQUENCY) BROADBAND OFDM SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Yang Lei; Zhang You'ai

    2008-01-01

    In this letter, a kind of associated synchronization algorithm which is suitable for HF (High Frequency) broadband OFDM (Orthogonal Frequency Division Multiplexing) system is presented based on describing and constructing the GMW (Gorden, Mills and Welch) sequence. The algorithm is based on the Schmidl and Minn's symbol timing principle, the constructed GMW sequence is transmitted and disposed, and the synchronization is adjudicated using the correlation of GMW sequence. The simulation result indicates that this algorithm has high performance synchronization ability under the low SNR (Signal to Noise Ratio) at two different kinds of channel models.

  12. Meteorite zircon constraints on the bulk Lu-Hf isotope composition and early differentiation of the Earth.

    Science.gov (United States)

    Iizuka, Tsuyoshi; Yamaguchi, Takao; Hibiya, Yuki; Amelin, Yuri

    2015-04-28

    Knowledge of planetary differentiation is crucial for understanding the chemical and thermal evolution of terrestrial planets. The (176)Lu-(176)Hf radioactive decay system has been widely used to constrain the timescales and mechanisms of silicate differentiation on Earth, but the data interpretation requires accurate estimation of Hf isotope evolution of the bulk Earth. Because both Lu and Hf are refractory lithophile elements, the isotope evolution can be potentially extrapolated from the present-day (176)Hf/(177)Hf and (176)Lu/(177)Hf in undifferentiated chondrite meteorites. However, these ratios in chondrites are highly variable due to the metamorphic redistribution of Lu and Hf, making it difficult to ascertain the correct reference values for the bulk Earth. In addition, it has been proposed that chondrites contain excess (176)Hf due to the accelerated decay of (176)Lu resulting from photoexcitation to a short-lived isomer. If so, the paradigm of a chondritic Earth would be invalid for the Lu-Hf system. Herein we report the first, to our knowledge, high-precision Lu-Hf isotope analysis of meteorite crystalline zircon, a mineral that is resistant to metamorphism and has low Lu/Hf. We use the meteorite zircon data to define the Solar System initial (176)Hf/(177)Hf (0.279781 ± 0.000018) and further to identify pristine chondrites that contain no excess (176)Hf and accurately represent the Lu-Hf system of the bulk Earth ((176)Hf/(177)Hf = 0.282793 ± 0.000011; (176)Lu/(177)Hf = 0.0338 ± 0.0001). Our results provide firm evidence that the most primitive Hf in terrestrial zircon reflects the development of a chemically enriched silicate reservoir on Earth as far back as 4.5 billion years ago.

  13. Thermodynamic modeling of the Co–Hf system supported by key experiments and first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xingxu [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Liu, Shuhong, E-mail: shhliu@csu.edu.cn [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Sino-German Cooperation Group “Microstructure in Al alloys”, Central South University, Changsha, Hunan 410083 (China); Cheng, Kaiming; Tang, Ying [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Ou, Pengfei [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Nash, Philip [Thermal Processing Technology Center, Illinois Institute of Technology (IIT), 10 West 32nd Street, Chicago, IL 60616 (United States); Sundman, Bo [INSTN, CEA Saclay, 91191 Gif-Sur-Yvette Cedex (France); Du, Yong [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Sino-German Cooperation Group “Microstructure in Al alloys”, Central South University, Changsha, Hunan 410083 (China); Zheng, Feng [School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083 (China)

    2015-05-20

    Highlights: • Heat contents of Co{sub 2}Hf and CoHf{sub 2} were measured by drop calorimetry. • Enthalpy of formation for Co{sub 23}Hf{sub 6} was computed via first-principles calculations. • Co–Hf system was assessed by means of CALPHAD approach. • Order–disorder model is used to describe B2 (CoHf) and A2 (βHf). • Glass forming range of the Co–Hf amorphous alloys was predicted. - Abstract: Phase equilibria and thermodynamic properties of the Co–Hf system were investigated via calorimetric measurements, first-principles calculations and thermodynamic modeling. Heat contents of Co{sub 2}Hf and CoHf{sub 2} were measured by drop calorimetry from 300 to 1200 °C. The enthalpy of formation for Co{sub 23}Hf{sub 6} at 0 K was computed via first-principles calculations. Based on the experimental measurements and first-principles calculations from the present work and the literature, the Co–Hf system was assessed by means of CALPHAD (CALculation of PHAse Diagram) approach. The excess Gibbs energy of solution phases was modeled with Redlich–Kister polynomial. Sublattice models were employed to describe the homogeneity ranges of Co{sub 2}Hf, CoHf and CoHf{sub 2}. The order–disorder transition between B2 (CoHf) and A2 (βHf) phases was taken into account in the current optimization. Using the optimized parameters, glass forming range (GFR) of the Co–Hf amorphous alloys was predicted to be 15–75 at.% Hf, which is in satisfactory agreement with the experimental observation.

  14. ALICE Transition Radiation Detector

    CERN Multimedia

    Pachmayer, Y

    2013-01-01

    The Transition Radiation Detector (TRD) is the main electron detector in ALICE. In conduction with the TPC and the ITS, it provides the necessary electron identification capability to study: - Production of light and heavy vector mesons as well as the continuum in the di-electron channel, - Semi leptonic decays of hadrons with open charm and open beauty via the single-electron channel using the displaced vertex information provided by the ITS, - Correlated DD and BB pairs via coincidences of electrons in the central barrel and muons in the forward muon arm, - Jets with high Pτ tracks in one single TRD stack.

  15. Edgeless silicon pad detectors

    Science.gov (United States)

    Perea Solano, B.; Abreu, M. C.; Avati, V.; Boccali, T.; Boccone, V.; Bozzo, M.; Capra, R.; Casagrande, L.; Chen, W.; Eggert, K.; Heijne, E.; Klauke, S.; Li, Z.; Mäki, T.; Mirabito, L.; Morelli, A.; Niinikoski, T. O.; Oljemark, F.; Palmieri, V. G.; Rato Mendes, P.; Rodrigues, S.; Siegrist, P.; Silvestris, L.; Sousa, P.; Tapprogge, S.; Trocmé, B.

    2006-05-01

    We report measurements in a high-energy pion beam of the sensitivity of the edge region in "edgeless" planar silicon pad diode detectors diced through their contact implants. A large surface current on such an edge prevents the normal reverse biasing of the device, but the current can be sufficiently reduced by the use of a suitable cutting method, followed by edge treatment, and by operating the detector at low temperature. The depth of the dead layer at the diced edge is measured to be (12.5±8 stat..±6 syst.) μm.

  16. Edgeless silicon pad detectors

    Energy Technology Data Exchange (ETDEWEB)

    Perea Solano, B. [CERN, CH-1211 Geneva 23 (Switzerland)]. E-mail: blanca.perea.solano@cern.ch; Abreu, M.C. [LIP and University of Algarve, 8000 Faro (Portugal); Avati, V. [CERN, CH-1211 Geneva 23 (Switzerland); Boccali, T. [INFN Sez. di Pisa and Scuola Normale Superiore, Pisa (Italy); Boccone, V. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Bozzo, M. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Capra, R. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Casagrande, L. [INFN Sez. di Roma 2 and Universita di Roma 2, Rome (Italy); Chen, W. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Eggert, K. [CERN, CH-1211 Geneva 23 (Switzerland); Heijne, E. [CERN, CH-1211 Geneva 23 (Switzerland); Klauke, S. [CERN, CH-1211 Geneva 23 (Switzerland); Li, Z. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Maeki, T. [Helsinki Institute of Physics, Helsinki (Finland); Mirabito, L. [CERN, CH-1211 Geneva 23 (Switzerland); Morelli, A. [INFN Sez. di Genova and Universita di Genova, Genoa (Italy); Niinikoski, T.O. [CERN, CH-1211 Geneva 23 (Switzerland); Oljemark, F. [Helsinki Institute of Physics, Helsinki (Finland); Palmieri, V.G. [Helsinki Institute of Physics, Helsinki (Finland); Rato Mendes, P. [LIP and University of Algarve, 8000 Faro (Portugal); Rodrigues, S. [LIP and University of Algarve, 8000 Faro (Portugal); Siegrist, P. [CERN, CH-1211 Geneva 23 (Switzerland); Silvestris, L. [INFN Sez. Di Bari, Bari (Italy); Sousa, P. [LIP and University of Algarve, 8000 Faro (Portugal); Tapprogge, S. [Helsinki Institute of Physics, Helsinki (Finland); Trocme, B. [Institut de Physique Nucleaire, Villeurbanne (France)

    2006-05-01

    We report measurements in a high-energy pion beam of the sensitivity of the edge region in 'edgeless' planar silicon pad diode detectors diced through their contact implants. A large surface current on such an edge prevents the normal reverse biasing of the device, but the current can be sufficiently reduced by the use of a suitable cutting method, followed by edge treatment, and by operating the detector at low temperature. The depth of the dead layer at the diced edge is measured to be (12.5{+-}8{sub stat.}.{+-}6{sub syst.}) {mu}m.

  17. Radiation Detectors and Art

    Science.gov (United States)

    Denker, Andrea

    The use of radiation detectors in the analysis of art objects represents a very special application in a true interdisciplinary field. Radiation detectors employed in this field detect, e.g., x-rays, γ-rays, β particles, and protons. Analyzed materials range from stones, metals, over porcelain to paintings. The available nondestructive and noninvasive analytical methods cover a broad range of techniques. Hence, for the sake of brevity, this chapter will concentrate on few techniques: Proton Induced X-ray Emission (PIXE) and Proton Induced γ-ray Emission (PIGE).

  18. Description of $^{178}$Hf$^{m2}$ in the constrained relativistic mean field theory

    CERN Document Server

    Wei, Zhang; Shuang-Quan, Zhang

    2009-01-01

    The properties of the ground state of $^{178}$Hf and the isomeric state $^{178}$Hf$^{m2}$ are studied within the adiabatic and diabatic constrained relativistic mean field (RMF) approaches. The RMF calculations reproduce well the binding energy and the deformation for the ground state of $^{178}$Hf. Using the ground state single-particle eigenvalues obtained in the present calculation, the lowest excitation configuration with $K^\\pi=16^+$ is found to be $\

  19. Assembly of the CMS HF (hadron forward) calorimeter, April 2003 to June 2005

    CERN Multimedia

    Tejinder S. Virdee, CERN

    2005-01-01

    The forward calorimeters (HF) of the CMS hadron calorimeter system are located 11.2 m from the interaction point. Each HF module is composed by 18 wedges, made of steel absorbers and radiation-hard quartz fibers. The photogallery shows the wedges (Figs. 1-3, April 2003), the assembly of one HF module (Figs. 4-9, May and June 2004) and the assembly of the other (Figs. 10-11, June 2005)

  20. Far-Field Testing Method of Spurious Emission Produced by HF RFID

    OpenAIRE

    Nikola Gvozdenovic; Ralph Prestros; Mecklenbräuker, Christoph F.

    2016-01-01

    We present measurements of spurious emission produced by high-frequency radio frequency identification (HF RFID) using carrier frequency of 13.56 MHz. HF RFID tags produce unwanted emission due to rectification and more generally due to nonlinearity of analog front end. Depending on the conducting material of an HF RFID coil and surrounding dielectric material, the coil behaves as more or less good antenna on some harmonic frequencies. Exact characterization and analysis of unwanted emission ...

  1. Enhanced resistive switching and multilevel behavior in bilayered HfAlO/HfAlO{sub x} structures for non-volatile memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Faita, F. L., E-mail: fabriciofaita@gmail.com [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Departamento de Física, Universidade Federal de Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC (Brazil); Silva, J. P. B., E-mail: josesilva@fisica.uminho.pt [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto (Portugal); Pereira, M.; Gomes, M. J. M. [Centre of Physics, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2015-12-14

    In this work, hafnium aluminum oxide (HfAlO) thin films were deposited by ion beam sputtering deposition technique on Si substrate. The presence of oxygen vacancies in the HfAlO{sub x} layer deposited in oxygen deficient environment is evidenced from the photoluminescence spectra. Furthermore, HfAlO(oxygen rich)/HfAlO{sub x}(oxygen poor) bilayer structures exhibit multilevel resistive switching (RS), and the switching ratio becomes more prominent with increasing the HfAlO layer thickness. The bilayer structure with HfAlO/HfAlO{sub x} thickness of 30/40 nm displays the enhanced multilevel resistive switching characteristics, where the high resistance state/intermediate resistance state (IRS) and IRS/low resistance state resistance ratios are ≈10{sup 2} and ≈5 × 10{sup 5}, respectively. The switching mechanisms in the bilayer structures were investigated by the temperature dependence of the three resistance states. This study revealed that the multilevel RS is attributed to the coupling of ionic conduction and the metallic conduction, being the first associated to the formation and rupture of conductive filaments related to oxygen vacancies and the second with the formation of a metallic filament. Moreover, the bilayer structures exhibit good endurance and stability in time.

  2. A digital X-ray imaging system based on silicon strip detectors working in edge-on configuration

    Energy Technology Data Exchange (ETDEWEB)

    Bolanos, L. [CEADEN, Calle 30 502 e/ 5ta y 7ma Avenida, Playa, Ciudad Habana (Cuba); Boscardin, M. [IRST, Fondazione Bruno Kessler, Via Sommarive 18, Povo, 38100 Trento (Italy); Cabal, A.E. [CEADEN, Calle 30 502 e/ 5ta y 7ma Avenida, Playa, Ciudad Habana (Cuba); Diaz, M. [InSTEC, Ave. Salvador Allende esq. Luaces, Quinta de los Molinos, Ciudad Habana (Cuba); Grybos, P.; Maj, P. [Faculty of Electrical Engineering, Automatics, Computer Science and Electronics, Department of Measurement and Instrumentation, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland); Prino, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Via P. Giuria 1, 10125 Torino (Italy); Ramello, L. [Dipartimento di Scienze e Tecnologie Avanzate, Universita del Piemonte Orientale, Via T. Michel 11, 15100 Alessandria (Italy)], E-mail: luciano.ramello@mfn.unipmn.it; Szczygiel, R. [Faculty of Electrical Engineering, Automatics, Computer Science and Electronics, Department of Measurement and Instrumentation, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow (Poland)

    2009-09-21

    We present the energy resolution and imaging performance of a digital X-ray imaging system based on a 512-strip silicon strip detector (SSD) working in the edge-on configuration. The SSDs tested in the system are 300 {mu}m thick with 1 or 2-cm-long strips and 100 {mu}m pitch. To ensure a very small dead area of the SSD working in edge-on configuration, the detector is cut perpendicular to the strips at a distance of only 20 {mu}m from the end of the strips. The 512-strip silicon detector is read out by eight 64-channel integrated circuits called DEDIX [Grybos et al., IEEE Trans. Nucl. Sci. NS-54 (2007) 1207]. The DEDIX IC operates in a single photon counting mode with two independent amplitude discriminators per channel. The readout electronic channel connected to a detector with effective input capacitance of about 2 pF has an average equivalent noise charge (ENC) of about 163 el. rms and is able to count 1 Mcps of average rate of input pulses. The system consisting of 512 channels has an excellent channel-to-channel uniformity-the effective threshold spread calculated to the charge-sensitive amplifier inputs is 12 el. rms (at one sigma level). With this system a few test images of a phantom have been taken in the 10-30 keV energy range.

  3. The Upgraded D0 Detector

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, D L; Adams, M; Adams, T; Agelou, M; Agram, J L; Ahmed, S N; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, J T; Anderson, S; Andrieu, B; Angstadt, R; Anosov, V; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Babukhadia, L; Bacon, Trevor C; Badaud, F; Baden, A; Baffioni, S; Bagby, L; Baldin, B; Balm, P W; Banerjee, P; Banerjee, S; Barberis, E; Bardon, O; Barg, W; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bhattacharjee, M; Baturitsky, M A; Bauer, D; Bean, A; Baumbaugh, B; Beauceron, S; Begalli, M; Beaudette, F; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Besson, A; Beuselinck, R; Beutel, D; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Bishoff, A; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Bockenthein, E; Bodyagin, V; Böhnlein, A; Boeriu, O; Bolton, T A; Bonamy, P; Bonifas, D; Borcherding, F; Borissov, G; Bos, K; Bose, T; Boswell, C; Bowden, M; Brandt, A; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, D; Butler, J M; Cammin, J; Caron, S; Bystrický, J; Canal, L; Canelli, F; Carvalho, W; Casey, B C K; Casey, D; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Chi, E; Chiche, R; Cho, D K; Choate, R; Choi, S; Choudhary, B; Chopra, S; Christenson, J H; Christiansen, T; Christofek, L; Churin, I; Cisko, G; Claes, D; Clark, A R; Clement, B; Clément, C; Coadou, Y; Colling, D J; Coney, L; Connolly, B; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M C; Cox, B; Crepe-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; Da Motta, H; Das, M; Davies, B; Davies, G; Davis, G A; Davis, W; De, K; de Jong, P; De Jong, S J; De La Cruz-Burelo, E; de La Taille, C; De Oliveira Martins, C; Dean, S; Degenhardt, J D; Déliot, F; Delsart, P A; Del Signore, K; De Maat, R; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doets, M; Doidge, M; Dong, H; Doulas, S; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dvornikov, O; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fagan, J; Fast, J; Fatakia, S N; Fein, D; Feligioni, L; Ferapontov, A V; Ferbel, T; Ferreira, M J; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Fitzpatrick, T; Flattum, E; Fleuret, F; Flores, R; Foglesong, J; Fortner, M; Fox, H; Franklin, C; Freeman, W; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Gao, M; García, C; García-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Yu; Gillberg, D; Geurkov, G; Ginther, G; Gobbi, B; Goldmann, K; Golling, T; Gollub, N; Golovtsov, V L; Gómez, B; Gómez, G; Gómez, R; Goodwin, R W; Gornushkin, Y; Gounder, K; Goussiou, A; Graham, D; Graham, G; Grannis, P D; Gray, K; Greder, S; Green, D R; Green, J; Green, J A; Greenlee, H; Greenwood, Z D; Gregores, E M; Grinstein, S; Gris, P; Grivaz, J F; Groer, L; Grünendahl, S; Grünewald, M W; Gu, W; Guglielmo, J; Sen-Gupta, A; Gurzhev, S N; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Haggard, E; Haggerty, H; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hance, R; Hanagaki, K; Hanlet, P; Hansen, S; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, C; Hays, J; Hazen, E; Hebbeker, T; Hebert, C; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Hou, S; Houben, P; Hu, Y; Huang, J; Huang, Y; Hynek, V; Huffman, D; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jacquier, Y; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jayanti, R; Jenkins, A; Jesik, R; Jiang, Y; Johns, K; Johnson, M; Johnson, P; Jonckheere, A; Jonsson, P; Jöstlein, H; Jouravlev, N I; Juárez, M; Juste, A; Kaan, A P; Kado, M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Kalmani, S D; Karmanov, D; Kasper, J; Katsanos, I; Kau, D; Kaur, R; Ke, Z; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Kim, H; Kim, K H; Kim, T J; Kirsch, N; Klima, B; Klute, M; Kohli, J M; Konrath, J P; Komissarov, E V; Kopal, M; Korablev, V M; Kostritskii, A V; Kotcher, J; Kothari, B; Kotwal, A V; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Kuznetsov, O; Krane, J; Kravchuk, N; Krempetz, K; Krider, J; Krishnaswamy, M R; Krzywdzinski, S; Kubantsev, M A; Kubinski, R; Kuchinsky, N; Kuleshov, S; Kulik, Y; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Kuznetsov, V E; Kwarciany, R; Lager, S; Lahrichi, N; Landsberg, G L; Larwill, M; Laurens, P; Lavigne, B; Lazoflores, J; Le Bihan, A C; Le Meur, G; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Leggett, C; Lehner, F; Leitner, R; Leonidopoulos, C; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Li, X; Lima, J G R; Lincoln, D; Lindenmeyer, C; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Litmaath, M; Lizarazo, J; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lü, J; Lubatti, H J; Lucotte, A; Lueking, L; Luo, C; Lynker, M; Lyon, A L; Machado, E; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A M; Maity, M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Manakov, V; Mao, H S; Maravin, Y; Markley, D; Markus, M; Marshall, T; Martens, M; Martin, M; Martin-Chassard, G; Mattingly, S E K; Matulik, M; Mayorov, A A; McCarthy, R; McCroskey, R; McKenna, M; McMahon, T; Meder, D; Melanson, H L; Melnitchouk, A S; Mendes, A; Mendoza, D; Mendoza, L; Meng, X; Merekov, Y P; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miao, C; Miettinen, H; Mihalcea, D; Mikhailov, V; Miller, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mostafa, M; Moua, S; Mulders, M; Mundim, L; Mutaf, Y D; Nagaraj, P; Nagy, E; Naimuddin, M; Nang, F; Narain, M; Narasimhan, V S; Narayanan, A; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neuenschwander, R T; Neustroev, P; Nöding, C; Nomerotski, A; Novaes, S F; Nozdrin, A; Nunnemann, T; Nurczyk, A; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Olis, D; Oliveira, N; Olivier, B; Olsen, J; Oshima, N; Oshinowo, B O; Oteroy-Garzon, G J; Padley, P; Papageorgiou, K; Parashar, N; Park, J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Pérez, E; Peters, O; Petroff, P; Petteni, M; Phaf, L; Piegaia, R; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Polosov, P; Pope, B G; Popkov, E; Porokhovoy, S; Prado da Silva, W L; Pritchard, W; Prokhorov, I; Prosper, H B; Protopopescu, S D; Przybycien, M B; Qian, J; Quadt, A; Quinn, B; Ramberg, E; Ramirez-Gomez, R; Rani, K J; Ranjan, K; Rao, M V S; Rapidis, P A; Rapisarda, S; Raskowski, J; Ratoff, P N; Ray, R E; Reay, N W; Rechenmacher, R; Reddy, L V; Regan, T; Renardy, J F; Reucroft, S; Rha, J; Ridel, M; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Roco, M T; Rotolo, C; Royon, C; Rubinov, P; Ruchti, R; Rucinski, R; Rud, V I; Rusakovich, N; Russo, P; Sabirov, B; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Satyanarayana, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schukin, A A; Schwartzman, A; Schwienhorst, R; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shankar, H C; Shary, V; Shchukin, A A; Sheahan, P; Shephard, W D; Shivpuri, R K; Shishkin, A A; Shpakov, D; Shupe, M; Sidwell, R A; Simák, V; Sirotenko, V I; Skow, D; Skubic, P L; Slattery, P F; Smith, D E; Smith, R P; Smolek, K; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Song, Y; Sonnenschein, L; Sopczak, A; Sorin, V; Sosebee, M; Soustruznik, K; Souza, M; Spartana, N; Spurlock, B; Stanton, N R; Stark, J; Steele, J; Stefanik, A; Steinberg, J L; Steinbruck, G; Stevenson, K; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Sznajder, A; Talby, M; Tentindo-Repond, S; Tamburello, P; Taylor, W; Telford, P; Temple, J; Terentyev, N K; Teterin, V; Thomas, E; Thompson, J; Thooris, B; Titov, M; Toback, D; Tokmenin, V V; Tolian, C; Tomoto, M; Tompkins, D; Toole, T; Torborg, J; Touze, F; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Trippe, T G; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Utes, M; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; Van den Berg, P J; Van Gemmeren, P; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Vaz, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Vigneault, M; Villeneuve-Séguier, F; Vishwanath, P R; Vlimant, J R; Von Törne, E; Vorobyov, A; Vreeswijk, M; Vu-Anh, T; Vysotsky, V S; Wahl, H D; Walker, R; Wallace, N; Wang, L; Wang, Z M; Warchol, J; Warsinsky, M; Watts, G; Wayne, M; Weber, M; Weerts, H; Wegner, M; Wermes, N; Wetstein, M; White, A; White, V; Whiteson, D; Wicke, D; Wijnen, T A M; Wijngaarden, D A; Wilcer, N; Willutzki, H; Wilson, G W; Wimpenny, S J; Wittlin, J; Wlodek, T; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Wu, Z; Xie, Y; Xu, Q; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yarema, R J; Yasuda, T; Yatsunenko, Y A; Yen, Y; Yip, K; Yoo, H D; Yoffe, F; Youn, S W; Yu, J; Yurkewicz, A; Zabi, A; Zanabria, M; Zatserklyaniy, A; Zdrazil, M; Zeitnitz, C; Zhang, B; Zhang, D; Zhang, X; Zhao, T; Zhao, Z; Zheng, H; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zitoun, R; Zmuda, T; Zutshi, V; Zviagintsev, S; Zverev, E G; Zylberstejn, A

    2005-01-01

    The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.

  4. The Upgraded D0 detector

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, D.L.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahmed, S.N.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G.A.; Anastasoaie, M.; Andeen, T.; Anderson, J.T.; Anderson, S.; /Buenos Aires U. /Rio de Janeiro, CBPF /Sao Paulo, IFT /Alberta U.

    2005-07-01

    The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid-argon calorimeters and central muon detector, remaining from Run I, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to D0.

  5. Status of the KEDR detector

    CERN Document Server

    Anashin, V V; Baibusinov, B O; Balashov, V; Baldin, E M; Barkov, L M; Barladyan, A K; Barnyakov, M Y; Baru, S E; Bedny, I; Beilin, D M; Blinov, A E; Blinov, V E; Bondarev, D V; Bondar, A E; Buzykaev, A R; Cantoni, P; Chilingarov, A G; Dneprovsky, L V; Eidelman, S I; Epifanov, D A; Frabetti, P L; Gaidarev, P B; Groshev, V R; Karpov, S V; Kiselev, V A; Klimenko, S G; Kolachev, G M; Kononov, S A; Kozlov, V N; Kravchenko, E A; Kulikov, V F; Kurdadze, L M; Kuzmin, A S; Kuznecov, S A; Lanni, F; Lelchuk, M Y; Leontiev, L A; Levichev, E B; Malyshev, V M; Manfredi, P F; Maslennikov, A L; Minakov, G D; Nagaslaev, V P; Naumenkov, A I; Nikitin, S A; Nomerotski, A; Onuchin, A P; Oreshkin, S B; Ovechkin, R; Palombo, F; Peleganchuk, S V; Petrosyan, S S; Pivovarov, S V; Poluektov, A O; Pospelov, G E; Protopopov, I Ya; Re, V; Romanov, L V; Root, N I; Ruban, A A; Savinov, G A; Shamov, A G; Shatilov, D; Shubin, M A; Shusharo, A I; Shwartz, B A; Sidorov, V A; Skovpen, Y I; Smakhtin, V P; Snopkov, R G; Sokolov, A V; Soukharev, A M; Talyshev, A A; Tayursky, V A; Telnov, V I; Tikhonov, Yu A; Todyshev, K Y; Usov, Y V; Vorobyev, A I; Yushkov, A N; Zatcepin, A V; Zhilich, V N

    2002-01-01

    KEDR is a general-purpose detector for experiments at the VEPP-4M e sup + e sup - -collider in the energy range 2E=2.0-12 GeV. All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/PSI meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.

  6. Status of the KEDR detector

    Energy Technology Data Exchange (ETDEWEB)

    Anashin, V.V.; Aulchenko, V.M.; Baibusinov, B.O.; Balashov, V.; Baldin, E.M.; Barkov, L.M.; Barladyan, A.K.; Barnyakov, M.Yu.; Baru, S.E.; Bedny, I.V.; Beilin, D.M.; Blinov, A.E.; Blinov, V.E.; Bondarev, D.V.; Bondar, A.E.; Buzykaev, A.R.; Cantoni, P.; Chilingarov, A.G.; Dneprovsky, L.V.; Eidelman, S.I.; Epifanov, D.A.; Frabetti, P.L.; Gaidarev, P.B.; Groshev, V.R.; Karpov, S.V.; Kiselev, V.A.; Klimenko, S.G.; Kolachev, G.M.; Kononov, S.A.; Kozlov, V.N.; Kravchenko, E.A.; Kulikov, V.F.; Kurdadze, L.M.; Kuzmin, A.S.; Kuznecov, S.A.; Lanni, F.; Lelchuk, M.Yu.; Leontiev, L.A.; Levichev, E.B.; Malyshev, V.M.; Manfredi, P.F.; Maslennikov, A.L.; Minakov, G.D.; Nagaslaev, V.P.; Naumenkov, A.; Nikitin, S.A.; Nomerotsky, A.; Onuchin, A.P.; Oreshkin, S.B.; Ovechkin, R.; Palombo, F.; Peleganchuk, S.V.; Petrosyan, S.S.; Pivovarov, S.V.; Poluektov, A.O.; Pospelov, G.E.; Protopopov, I.Ya.; Re, V.; Romanov, L.V.; Root, N.I.; Ruban, A.A.; Savinov, G.A.; Shamov, A.G.; Shatilov, D.; Shubin, M.A.; Shusharo, A.I.; Shwartz, B.A.; Sidorov, V.A.; Skovpen, Yu.I.; Smakhtin, V.P.; Snopkov, R.G.; Sokolov, A.V.; Soukharev, A.M.; Talyshev, A.A.; Tayursky, V.A.; Telnov, V.I.; Tikhonov, Yu.A. E-mail: tikhonov@cppm.in2p3.fr; Todyshev, K.Yu.; Usov, Yu.V.; Vorobyev, A.I.; Yushkov, A.N.; Zatcepin, A.V.; Zhilich, V.N

    2002-02-01

    KEDR is a general-purpose detector for experiments at the VEPP-4M e{sup +}e{sup -}-collider in the energy range 2E=2.0-12 GeV. All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/{psi} meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.

  7. Ferroelectric phase stabilization of HfO2 by nitrogen doping

    Science.gov (United States)

    Xu, Lun; Nishimura, Tomonori; Shibayama, Shigehisa; Yajima, Takeaki; Migita, Shinji; Toriumi, Akira

    2016-09-01

    We report that nitrogen (N) doping can drive the ferroelectricity of HfO2. It was found that N doping can cause the transition from a monoclinic phase to a highly symmetric phase. The role of N doping is discussed from the viewpoints of charge balance and bond-constraining effects. The former is responsible for the structural transformation from a paraelectric phase to a ferroelectric phase by forming an oxygen vacancy. In addition, Hf-N and N-O bonds with covalent characteristics have strong effects on HfO2 structural and electrical properties, and thus contribute to a marked HfO2 para-/ferroelectric transition.

  8. Efficient noble metal nanocatalysts supported on HfC(001 for O2 dissociation

    Directory of Open Access Journals (Sweden)

    Shiyan Wang

    2017-03-01

    Full Text Available The adsorption and dissociation of O2 on the M4 (M=Au, Pd, Pt clusters supported on HfC(001 (Hafnium Carbide are investigated using ab initio density functional theory calculations. The geometric and electronic structures are analyzed in detail. It is found that the dissociation barriers of O2 on Au4/HfC(001 (0.26 eV, Pd4/HfC(001 (0.49 eV and Pt4/HfC(001 (0.09 eV are much smaller than those on the clean surfaces of HfC(001 (1.60 eV, Au(111 (1.37 eV, Pd(111 (1.0 and 0.91 eV and Pt(111 (0.27–0.7 eV, respectively. The low dissociation barriers imply that the Pt4/HfC(001 exhibits the highest catalytic activity for O2 dissociation, and the Au4/HfC(001 and Pd4/HfC(001 may also be possible substitutes with lower cost for the current Pt/C catalyst for O2 dissociation. The present study is conductive to designing new efficient noble metal catalyst using HfC support for efficiently promoting O2 dissociation.

  9. Efficient noble metal nanocatalysts supported on HfC(001) for O2 dissociation

    Science.gov (United States)

    Wang, Shiyan; Zhang, Xilin; Zhang, Yanxing; Mao, Jianjun; Yang, Zongxian

    2017-03-01

    The adsorption and dissociation of O2 on the M4 (M=Au, Pd, Pt) clusters supported on HfC(001) (Hafnium Carbide) are investigated using ab initio density functional theory calculations. The geometric and electronic structures are analyzed in detail. It is found that the dissociation barriers of O2 on Au4/HfC(001) (0.26 eV), Pd4/HfC(001) (0.49 eV) and Pt4/HfC(001) (0.09 eV) are much smaller than those on the clean surfaces of HfC(001) (1.60 eV), Au(111) (1.37 eV), Pd(111) (1.0 and 0.91 eV) and Pt(111) (0.27-0.7 eV), respectively. The low dissociation barriers imply that the Pt4/HfC(001) exhibits the highest catalytic activity for O2 dissociation, and the Au4/HfC(001) and Pd4/HfC(001) may also be possible substitutes with lower cost for the current Pt/C catalyst for O2 dissociation. The present study is conductive to designing new efficient noble metal catalyst using HfC support for efficiently promoting O2 dissociation.

  10. Study of Direct-Contact HfO2/Si Interfaces

    Directory of Open Access Journals (Sweden)

    Noriyuki Miyata

    2012-03-01

    Full Text Available Controlling monolayer Si oxide at the HfO2/Si interface is a challenging issue in scaling the equivalent oxide thickness of HfO2/Si gate stack structures. A concept that the author proposes to control the Si oxide interface by using ultra-high vacuum electron-beam HfO2 deposition is described in this review paper, which enables the so-called direct-contact HfO2/Si structures to be prepared. The electrical characteristics of the HfO2/Si metal-oxide-semiconductor capacitors are reviewed, which suggest a sufficiently low interface state density for the operation of metal-oxide-semiconductor field-effect-transistors (MOSFETs but reveal the formation of an unexpected strong interface dipole. Kelvin probe measurements of the HfO2/Si structures provide obvious evidence for the formation of dipoles at the HfO2/Si interfaces. The author proposes that one-monolayer Si-O bonds at the HfO2/Si interface naturally lead to a large potential difference, mainly due to the large dielectric constant of the HfO2. Dipole scattering is demonstrated to not be a major concern in the channel mobility of MOSFETs.

  11. Structural degradation of thin HfO2 film on Ge during the postdeposition annealing

    Science.gov (United States)

    Miyata, Noriyuki; Yasuda, Tetsuji; Abe, Yasuhiro

    2010-05-01

    Securing the thermal robustness of thin hafnium oxide (HfO2) film on the semiconductor surface is an important technical issue in the fabrication of the metal-oxide-semiconductor field-effect transistor devices, as the HfO2-based high-k gate stacks usually undergo high-temperature processes. In this study, the structural development of thin HfO2 film on a Ge surface during postdeposition annealing in an ultrahigh vacuum was examined to explore the origin for the initial degradation of thin HfO2 film. Void nucleation and subsequent two-dimensional void growth take place at 780-840 °C, while the chemical composition of the remaining Hf oxide is virtually stable. Both the void nucleation and growth processes show similar larger activation energy of about 10 eV. Based on the observed manner of void growth and the estimated activation energies, the authors propose that mass transport on the HfO2 surface is responsible for void nucleation in the HfO2 films on Ge. The authors also compare the present results with the previous studies on HfO2/Si structures, and suggest that similar surface process leads to the local Hf silicidation.

  12. The effect of Cu doping concentration on resistive switching of HfO{sub 2} film

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Tingting; Tan, Tingting, E-mail: tantt@nwpu.edu.cn; Liu, Zhengtang

    2015-10-01

    Graphical abstract: - Highlights: • The Cu doped and undoped HfO{sub 2} films were fabricated. • The improved RS behaviors were observed for Cu doped HfO{sub 2} film with BRS. • The 9.7% doped HfO{sub 2}:Cu film showed both BRS and URS behaviors. • The related switching mechanisms were illustrated. - Abstract: The Cu-doped and undoped HfO{sub 2} films were fabricated and the effect of Cu doping concentration on resistive switching (RS) of HfO{sub 2} film was demonstrated. The X-ray photoelectron spectroscopy (XPS) was carried out to investigate the chemical bonding states of Cu in HfO{sub 2}:Cu film. The improved RS behaviors in terms of ON/OFF ratio and switching parameters were observed for Cu-doped HfO{sub 2} film with bipolar resistive switching (BRS) behavior. With the increase of Cu doping concentration, the 9.7% Cu-doped HfO{sub 2} film showed both BRS and unipolar resistive switching (URS) behaviors with large operating voltages. The space charge limited current (SCLC) effect was proposed to interpret the switching mechanism of HfO{sub 2}:Cu films with BRS behavior and the URS behavior can be explained by the migration of Cu ions.

  13. Lu-hf total-rock isochron for the eucrite meteorites

    Science.gov (United States)

    Patchett, P.J.; Tatsumoto, M.

    1980-01-01

    The isotope 176Lu (2.6% of natural lutetium) decays by ??- to 176Hf, with a long half life. We present here the first Lu-Hf isochron. The eucrite meteorites, a suite of planetary igneous rocks of known age, 4,550 Myr, define a 10-point total-rock isochron with a slope of 0.0934 ?? 40, leading to a value of 3.53 ?? 0.14 ??1010yr for the ??--decay half life of 176Lu. The isochron intercept of 0.27973 ?? 12 gives the initial 176Hf/177Hf for the inner Solar System at the time of accretion. ?? 1980 Nature Publishing Group.

  14. Chemical stability and defect formation in CaHfO3

    KAUST Repository

    Alay-E-Abbas, Syed Muhammad

    2014-04-01

    Defects in CaHfO3 are investigated by ab initio calculations based on density functional theory. Pristine and anion-deficient CaHfO 3 are found to be insulating, whereas cation-deficient CaHfO 3 is hole-doped. The formation energies of neutral and charged cation and anion vacancies are evaluated to determine the stability in different chemical environments. Moreover, the energies of the partial and full Schottky defect reactions are computed. We show that clustering of anion vacancies in the HfO layers is energetically favorable for sufficiently high defect concentrations and results in metallicity. © 2014 EPLA.

  15. Anticooperativity of FHF hydrogen bonds in clusters of the type F- × (HF)n, RF × (HF)n and XF × (HF)n, R = alkyl and X = H, Br, Cl, F

    Science.gov (United States)

    Kucherov, S. Yu.; Bureiko, S. F.; Denisov, G. S.

    2016-02-01

    Properties of twenty five hydrogen-bonded complexes, namely, F- × (HF)n (n = 1-6), RF × (HF)n (R = t-Bu, i-Pr, Et, Me; n = 1-3), XF × (HF)n (X = H, Br, Cl; n = 1-2), and FF…HF with the hydrogen bond energy varying in a wide range have been calculated using ab initio methods at the MP2/6-31++G** level. For the first time, the energies, geometrical parameters and vibrational frequencies are obtained for the series of clusters, where the bonding character changes from covalent to van der Waals on the variation of proton-acceptor ability of the base, and the energies are in the range of 45-1 kcal/mol. The mutual influence of multiple hydrogen bonds of F…HF type in clusters, in which a fluorine anion or an atom participates in hydrogen bond formation as the acceptor, is systematically investigated. The relative changes in the values of the considered parameters on the sequential addition of an HF molecule (anticooperativity) were determined. It was shown that non-additivity of the interaction is most strongly pronounced in the energy and vibrational frequency values, geometrical parameters of hydrogen bonds are less sensitive to the mutual influence. The anticooperative effect is more pronounced on the hydrogen bridge length R(F...F) than on the geometry of proton donor r(HF). The hydrogen bond formation and the increase of the number n of ligands lead to successive lengthening of the r(XF) bond adjacent to the hydrogen bridge. The length of an XF bond changes stronger on formation of each hydrogen bond than the HF bond length.

  16. Modeling Attitude Dynamics in Simulink: A Study of the Rotational and Translational Motion of a Spacecraft Given Torques and Impulses Generated by RMS Hand Controllers

    Science.gov (United States)

    Mauldin, Rebecca H.

    2010-01-01

    In order to study and control the attitude of a spacecraft, it is necessary to understand the natural motion of a body in orbit. Assuming a spacecraft to be a rigid body, dynamics describes the complete motion of the vehicle by the translational and rotational motion of the body. The Simulink Attitude Analysis Model applies the equations of rigid body motion to the study of a spacecraft?s attitude in orbit. Using a TCP/IP connection, Matlab reads the values of the Remote Manipulator System (RMS) hand controllers and passes them to Simulink as specified torque and impulse profiles. Simulink then uses the governing kinematic and dynamic equations of a rigid body in low earth orbit (LE0) to plot the attitude response of a spacecraft for five seconds given known applied torques and impulses, and constant principal moments of inertia.

  17. Effects of Hf Incorporation on Negative Bias-Illumination Stress Stability in Hf-In-Zn-O Thin-Film Transistors

    Science.gov (United States)

    Kim, Sangwook; Park, Jae Chul; Kim, Dae Hwan; Lee, Jang-Sik

    2013-04-01

    In this study, highly reliable amorphous oxide semiconductor-based thin-film transistors (TFTs) were developed. The Hf concentration was systematically changed in the Hf-incorporated In-Zn-O (HIZO) TFTs, and Hf played an important role in determining the negative bias-illumination instability. The process parameters were optimized in order to obtain HIZO TFTs with an excellent stability. HIZO can be processed on a 6-in. wafer at low temperatures and is almost transparent in the visible range. Thus this material is promising for use in current TFTs as well as future transparent electronic device components with good electrical performance and excellent stability.

  18. Discovery and Monitoring of a New Black Hole Candidate XTE J1752-223 with RXTE: RMS Spectrum Evolution, BH Mass and the Source Distance

    Science.gov (United States)

    Shaposhinikov, Nikolai; Markwardt, Craig; Swank, Jean; Krimm, Hans

    2010-01-01

    We report on the discovery and monitoring observations of a new galactic black hole candidate XTE J1752-223 by Rossi X-ray Timing Explorer (RXTE). The new source appeared on the X-ray sky on October 21 2009 and was active for almost 8 months. Phenomenologically, the source exhibited the low-hard/highsoft spectral state bi-modality and the variability evolution during the state transition that matches standard behavior expected from a stellar mass black hole binary. We model the energy spectrum throughout the outburst using a generic Comptonization model assuming that part of the input soft radiation in the form of a black body spectrum gets reprocessed in the Comptonizing medium. We follow the evolution of fractional root-mean-square (RMS) variability in the RXTE/PCA energy band with the source spectral state and conclude that broad band variability is strongly correlated with the source hardness (or Comptonized fraction). We follow changes in the energy distribution of rms variability during the low-hard state and the state transition and find further evidence that variable emission is strongly concentrated in the power-law spectral component. We discuss the implication of our results to the Comptonization regimes during different spectral states. Correlations of spectral and variability properties provide measurements of the BH mass and distance to the source. The spectral-timing correlation scaling technique applied to the RXTE observations during the hardto- soft state transition indicates a mass of the BH in XTE J1752-223 between 8 and 11 solar masses and a distance to the source about 3.5 kiloparsec.

  19. Fast Detector Simulation Using Lelaps, Detector Descriptions in GODL

    Energy Technology Data Exchange (ETDEWEB)

    Langeveld, Willy; /SLAC

    2005-07-06

    Lelaps is a fast detector simulation program which reads StdHep generator files and produces SIO or LCIO output files. It swims particles through detectors taking into account magnetic fields, multiple scattering and dE/dx energy loss. It simulates parameterized showers in EM and hadronic calorimeters and supports gamma conversions and decays. In addition to three built-in detector configurations, detector descriptions can also be read from files in the new GODL file format.

  20. Phase1 upgrade of the CMS-HF Calorimeter

    CERN Document Server

    Gulmez, Erhan

    2016-01-01

    In this presentation, results of the Phase I upgrade of the CMS Hadron Forward Calorimeter (HF) are discussed. The CMS-HF Calorimeter was using regular PMTs. Cherenkov light produced in the quartz fibers embedded in the iron absorber was read out with the PMTs. However, occasionally, stray muons hitting the PMT windows cause Cherenkov radiation in the PMT itself and produce large signals. These large signals mimic a very high-energy particle and are tagged as important by the trigger. To reduce this problem, PMTs had to be replaced. The four-anode PMTs that were chosen have thinner windows; thereby reducing the Cherenkov radiation in the PMT window. As part of the upgrade, the read-out electronics is to be replaced so that the PMTs are read out in two channels by connecting each pair of anodes to a single channel. Information provided by these two channels will help us reject the false signals due to the stray muons since the Cherenkov radiation in the PMT window is more likely to produce a signal only in one...

  1. Reversible spin texture in ferroelectric Hf O2

    Science.gov (United States)

    Tao, L. L.; Paudel, Tula R.; Kovalev, Alexey A.; Tsymbal, Evgeny Y.

    2017-06-01

    Spin-orbit coupling effects occurring in noncentrosymmetric materials are known to be responsible for nontrivial spin configurations and a number of emergent physical phenomena. Ferroelectric materials may be especially interesting in this regard due to reversible spontaneous polarization making possible a nonvolatile electrical control of the spin degrees of freedom. Here, we explore a technologically relevant oxide material, Hf O2 , which has been shown to exhibit robust ferroelectricity in a noncentrosymmetric orthorhombic phase. Using theoretical modelling based on density-functional theory, we investigate the spin-dependent electronic structure of the ferroelectric Hf O2 and demonstrate the appearance of chiral spin textures driven by spin-orbit coupling. We analyze these spin configurations in terms of the Rashba and Dresselhaus effects within the k .p Hamiltonian model and find that the Rashba-type spin texture dominates around the valence-band maximum, while the Dresselhaus-type spin texture prevails around the conduction band minimum. The latter is characterized by a very large Dresselhaus constant λD= 0.578 eV Å, which allows using this material as a tunnel barrier to produce tunneling anomalous and spin Hall effects that are reversible by ferroelectric polarization.

  2. Radiation effects in Zr and Hf containing garnets

    Energy Technology Data Exchange (ETDEWEB)

    Whittle, Karl R. [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, PMB1, Menai, NSW 2234 (Australia); Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Blackford, Mark G.; Smith, Katherine L. [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, PMB1, Menai, NSW 2234 (Australia); Zaluzec, Nestor J. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Weyland, Matthew [Monash Centre for Electron Microscopy, Monash University, Victoria 3800 (Australia); Department of Materials Engineering, Monash University, Victoria 3800 (Australia); Lumpkin, Gregory R. [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, PMB1, Menai, NSW 2234 (Australia)

    2015-07-15

    Garnets have been considered as host phases for the safe immobilisation of high-level nuclear waste, as they have been shown to accommodate a wide range of elements across three different cation sites, such as Ca, Y, Mn on the a-site, Fe, Al, U, Zr, and Ti on the b-site, and Si, Fe, Al on the c-site. Garnets, due to their ability to have variable composition, make ideal model materials for the examination of radiation damage and recovery in nuclear materials, including as potential waste forms. Kimzeyite, Ca{sub 3}Zr{sub 2}FeAlSiO{sub 12}, has been shown naturally to contain up to 30 wt% Zr, and has previously been examined to elucidate both the structure and ordering within the lattice. This study examines the effects of radiation damage and recovery using in-situ ion beam irradiation with 1 MeV Kr ions at the IVEM-TANDEM facility, Argonne National Laboratory. The complementary Hf containing system Ca{sub 3}Hf{sub 2}FeAlSiO{sub 12} was also examined, and found to have a different response to irradiation damage. A sample of irradiated Ca{sub 3}Zr{sub 2}FeAlSiO{sub 12}, at 1000 K, was characterised using aberration corrected (S)TEM and found to contain discreet, nano-sized, crystalline Fe rich particles, indicating a competing process during recovery is occurring.

  3. Observations of HF backscatter decay rates from HAARP generated FAI

    Science.gov (United States)

    Bristow, W. A.; Hysell, D. L.

    2016-12-01

    Suitable experiments at the High-frequency Active Auroral Research Program (HAARP) facilities in Gakona, Alaska, create a region of ionospheric Field-Aligned Irregularities (FAI) that produces strong radar backscatter observed by the SuperDARN radar on Kodiak Island, Alaska. Creation of FAI in HF ionospheric modification experiments has been studied by a number of authors who have developed a rich theoretical background. The decay of the irregularities, however, has not been so widely studied yet it has the potential for providing estimates of the parameters of natural irregularity diffusion, which are difficult measure by other means. Hysell, et al. [1996] demonstrated using the decay of radar scatter above the Sura heating facility to estimate irregularity diffusion. A large database of radar backscatter from HAARP generated FAI has been collected over the years. Experiments often cycled the heater power on and off in a way that allowed estimates of the FAI decay rate. The database has been examined to extract decay time estimates and diffusion rates over a range of ionospheric conditions. This presentation will summarize the database and the estimated diffusion rates, and will discuss the potential for targeted experiments for aeronomy measurements. Hysell, D. L., M. C. Kelley, Y. M. Yampolski, V. S. Beley, A. V. Koloskov, P. V. Ponomarenko, and O. F. Tyrnov, HF radar observations of decaying artificial field aligned irregularities, J. Geophys. Res. , 101, 26,981, 1996.

  4. Observations of HF backscatter decay rates from HAARP generated FAI

    Science.gov (United States)

    Bristow, William; Hysell, David

    2016-07-01

    Suitable experiments at the High-frequency Active Auroral Research Program (HAARP) facilities in Gakona, Alaska, create a region of ionospheric Field-Aligned Irregularities (FAI) that produces strong radar backscatter observed by the SuperDARN radar on Kodiak Island, Alaska. Creation of FAI in HF ionospheric modification experiments has been studied by a number of authors who have developed a rich theoretical background. The decay of the irregularities, however, has not been so widely studied yet it has the potential for providing estimates of the parameters of natural irregularity diffusion, which are difficult measure by other means. Hysell, et al. [1996] demonstrated using the decay of radar scatter above the Sura heating facility to estimate irregularity diffusion. A large database of radar backscatter from HAARP generated FAI has been collected over the years. Experiments often cycled the heater power on and off in a way that allowed estimates of the FAI decay rate. The database has been examined to extract decay time estimates and diffusion rates over a range of ionospheric conditions. This presentation will summarize the database and the estimated diffusion rates, and will discuss the potential for targeted experiments for aeronomy measurements. Hysell, D. L., M. C. Kelley, Y. M. Yampolski, V. S. Beley, A. V. Koloskov, P. V. Ponomarenko, and O. F. Tyrnov, HF radar observations of decaying artificial field aligned irregularities, J. Geophys. Res. , 101, 26,981, 1996.

  5. Interrogation zone determination in HF RFID systems with multiplexed antennas*

    Directory of Open Access Journals (Sweden)

    Jankowski-Mihułowicz Piotr

    2015-09-01

    Full Text Available The operation of an anti-collision RFID system is characterized by the interrogation zone which should be estimated in any direction of 3D space for a group of electronic transponders. The interrogation zone should be as large as possible. However, the many problems in this area are due to the fact that energy can be transferred to transponders only on a limited distance. The greatest flexibility in developing RFID applications and shaping the interrogation zone can be achieved using the system with an antenna multiplexer. Therefore the problem of the interrogation zone determination in HF RFID systems with two orthogonal RWD antennas is presented in the paper. The perceived issues have been effectively dealt with and the solution has been proposed on the basis of the elaborated model. Conducted studies have been used to develop the software tool JankoRFIDmuxHF in the Mathcad environment. The research results are analysed in an example system configuration. The specialized measuring stand has been used for experimental verification of the identification efficiency. The convergence of the measurements and calculations confirms a practical usefulness of the presented concept of interrogation zone determination in anti-collision systems. It also shows the practical utility of the developed model and software tools.

  6. Pixel detector insertion

    CERN Multimedia

    CMS

    2015-01-01

    Insertion of the Pixel Tracker, the 66-million-channel device used to pinpoint the vertex of each colliding proton pair, located at the heart of the detector. The geometry of CMS is a cylinder lying on its side (22 meters long and 15 meters high in dia

  7. Sensitive hydrogen leak detector

    Science.gov (United States)

    Myneni, Ganapati Rao

    1999-01-01

    A sensitive hydrogen leak detector system using passivation of a stainless steel vacuum chamber for low hydrogen outgassing, a high compression ratio vacuum system, a getter operating at 77.5 K and a residual gas analyzer as a quantitative hydrogen sensor.

  8. B-factory detectors

    CERN Document Server

    Marlow, D R

    2002-01-01

    The designs of the recently commissioned BaBar and Belle B-Factory detectors are described. The discussion is organized around the methods and instruments used to detect the so-called gold-plated-mode B sup 0->J/PSI K sub S decays and related modes.

  9. The BABAR Detector

    CERN Document Server

    CERN. Geneva

    2002-01-01

    BABAR, the detector for the SLAC PEP-II asymmetric e+e- B Factory operating at the upsilon 4S resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

  10. CALIBRATION OF PHOSWICH DETECTORS

    NARCIS (Netherlands)

    LEEGTE, HKW; KOLDENHOF, EE; BOONSTRA, AL; WILSCHUT, HW

    1992-01-01

    Two important aspects for the calibration of phoswich detector arrays have been investigated. It is shown that common gate ADCs can be used: The loss in particle identification due to fluctuations in the gate timing in multi-hit events can be corrected for by a simple procedure using the measured ti

  11. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2012-01-01

    The RPC system is operating with a very high uptime, an average chamber efficiency of about 95% and an average cluster size around 1.8. The average number of active channels is 97.7%. Eight chambers are disconnected and forty are working in single-gap mode due to high-voltage problems. The total luminosity lost due to RPCs in 2012 is 88.46 pb–1. One of the main goals of 2012 was to improve the stability of the endcap trigger that is strongly correlated to the performances of the detector, due to the 3-out-3 trigger logic. At beginning of 2011 the instability of the detector efficiency was about 10%. Detailed studies found that this was mainly due to the strong correlation between the performance of the detector and the atmospheric pressure (P). Figure XXY shows the linear correlation between the average cluster size of the endcap chamber versus P. This effect is expected for gaseous detectors and can be reduced by correcting the applied high-voltage working point (HVapp) according to the followi...

  12. Ionic smoke detectors

    CERN Document Server

    2002-01-01

    Ionic smoke detectors are products incorporating radioactive material. This article summarises the process for their commercialization and marketing, and how the activity is controlled, according to regulations establishing strict design and production requisites to guarantee the absence of radiological risk associated both with their use and their final handling as conventional waste. (Author)

  13. ALICE Silicon Pixel Detector

    CERN Multimedia

    Manzari, V

    2013-01-01

    The Silicon Pixel Detector (SPD) forms the innermost two layers of the 6-layer barrel Inner Tracking System (ITS). The SPD plays a key role in the determination of the position of the primary collision and in the reconstruction of the secondary vertices from particle decays.

  14. The CLIC Vertex Detector

    CERN Document Server

    Dannheim, D

    2015-01-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a meas- urement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → W b will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit tim- ing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC ver- tex det...

  15. First ALICE detectors installed!

    CERN Multimedia

    2006-01-01

    Detectors to track down penetrating muon particles are the first to be placed in their final position in the ALICE cavern. The Alice muon spectrometer: in the foreground the trigger chamber is positioned in front of the muon wall, with the dipole magnet in the background. After the impressive transport of its dipole magnet, ALICE has begun to fill the spectrometer with detectors. In mid-July, the ALICE muon spectrometer team achieved important milestones with the installation of the trigger and the tracking chambers of the muon spectrometer. They are the first detectors to be installed in their final position in the cavern. All of the eight half planes of the RPCs (resistive plate chambers) have been installed in their final position behind the muon filter. The role of the trigger detector is to select events containing a muon pair coming, for instance, from the decay of J/ or Y resonances. The selection is made on the transverse momentum of the two individual muons. The internal parts of the RPCs, made o...

  16. Superconducting Single Photon Detectors

    NARCIS (Netherlands)

    Dorenbos, S.N.

    2011-01-01

    This thesis is about the development of a detector for single photons, particles of light. New techniques are being developed that require high performance single photon detection, such as quantum cryptography, single molecule detection, optical radar, ballistic imaging, circuit testing and fluoresc

  17. The BABAR Detector

    Energy Technology Data Exchange (ETDEWEB)

    Luth, Vera G

    2001-05-18

    BABAR, the detector for the SLAC PEP-II asymmetric e{sup +}e{sup -} B Factory operating at the {Upsilon}(4S) resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

  18. The role of Upper Hybrid Turbulence on HF Artificial Ionization

    Science.gov (United States)

    Papadopoulos, Konstantinos Dennis; Najmi, Amir; Eliasson, Bengt; Milikh, Gennady

    2016-07-01

    One of the most fascinating and scientifically interesting phenomena of active space experiments is the discovery of artificial ionization by Todd Pedersen when the HAARP ERP reached the GW level. The phenomenon has been well documented experimentally. A theoretical model based on ionization by energetic electrons accelerated by 50-100 V/m localized electric fields due to Strong Langmuir Turbulence (SLT) near the reflection surface of the HF pump wave, reproduced the observed dynamics of the descending plasma layer quite accurately. A major defect of the model was that the electron temperature in the SLT region was a free parameter. When taken as the 2000 K representing the ambient electron temperature the SLT driven electron flux was insufficient to produce ionization. An equivalent electron temperature of 5000 K or higher was necessary to reproduce the observations. The needed electron heating was attributed to the interaction of the HF at the Upper Hybrid (UH) resonant layer, approximately 5 Km below the reflection region where the HF electric field is perpendicular to the ambient magnetic field. The heated electrons expanded upwards along the magnetic field line and interacted with SLT fields near the resonance region. A consequence of this defect was that the theory could not explain the puzzling double resonance effect. Namely the observation that the ionization level was much stronger when the HF frequency and the UH resonance were a multiple of the electron cyclotron frequency. To remedy this we used a series of Vlasov simulations to explore the HF-plasma interaction in the vicinity of the UH resonance. The simulations followed the evolution of the spectral density of the electric field over a 7.5 MHz frequency band and cm scale lengths and of the electron distribution function over one millisecond for both double resonant and non-resonant cases. Many new features were revealed by the analysis of the simulations such as: 1. Broadening of the wave

  19. High-resolution ionization detector and array of such detectors

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S. (Ypsilanti, MI); Rojeski, Ronald A. (Pleasanton, CA)

    2001-01-16

    A high-resolution ionization detector and an array of such detectors are described which utilize a reference pattern of conductive or semiconductive material to form interaction, pervious and measurement regions in an ionization substrate of, for example, CdZnTe material. The ionization detector is a room temperature semiconductor radiation detector. Various geometries of such a detector and an array of such detectors produce room temperature operated gamma ray spectrometers with relatively high resolution. For example, a 1 cm.sup.3 detector is capable of measuring .sup.137 Cs 662 keV gamma rays with room temperature energy resolution approaching 2% at FWHM. Two major types of such detectors include a parallel strip semiconductor Frisch grid detector and the geometrically weighted trapezoid prism semiconductor Frisch grid detector. The geometrically weighted detector records room temperature (24.degree. C.) energy resolutions of 2.68% FWHM for .sup.137 Cs 662 keV gamma rays and 2.45% FWHM for .sup.60 Co 1.332 MeV gamma rays. The detectors perform well without any electronic pulse rejection, correction or compensation techniques. The devices operate at room temperature with simple commercially available NIM bin electronics and do not require special preamplifiers or cooling stages for good spectroscopic results.

  20. Electron Microprobe Analysis of Hf in Zircon: Suggestions for Improved Accuracy of a Difficult Measurement

    Science.gov (United States)

    Fournelle, J.; Hanchar, J. M.

    2013-12-01

    It is not commonly recognized as such, but the accurate measurement of Hf in zircon is not a trivial analytical issue. This is important to assess because Hf is often used as an internal standard for trace element analyses of zircon by LA-ICPMS. The issues pertaining to accuracy revolve around: (1) whether the Hf Ma or the La line is used; (2) what accelerating voltage is applied if Zr La is also measured, and (3) what standard for Hf is used. Weidenbach, et al.'s (2004) study of the 91500 zircon demonstrated the spread (in accuracy) of possible EPMA values for six EPMA labs, 2 of which used Hf Ma, 3 used Hf La, and one used Hf Lb, and standards ranged from HfO2, a ZrO2-HfO2 compound, Hf metal, and hafnon. Weidenbach, et al., used the ID-TIMS values as the correct value (0.695 wt.% Hf.), for which not one of the EPMA labs came close to that value (3 were low and 3 were high). Those data suggest: (1) that there is a systematic underestimation error of the 0.695 wt% Hf (ID-TIMS Hf) value if Hf Ma is used; most likely an issue with the matrix correction, as the analytical lines and absorption edges of Zr La, Si Ka and Hf Ma are rather tightly packed in the electromagnetic spectrum. Mass absorption coefficients are easily in error (e.g., Donovan's determination of the MAC of Hf by Si Ka of 5061 differs from the typically used Henke value of 5449 (Donovan et al, 2002); and (2) For utilization of the Hf La line, however, the second order Zr Ka line interferes with Hf La if the accelerating voltage is greater than 17.99 keV. If this higher keV is used and differential mode PHA is applied, only a portion of the interference is removed (e.g., removal of escape peaks), causing an overestimation of Hf content. Unfortunately, it is virtually impossible to apply an interference correction in this case, as it is impossible to locate Hf-free Zr probe standard. We have examined many of the combinations used by those six EPMA labs and concluded that the optimal EPMA is done with Hf

  1. Fire Emulator/Detector Evaluator

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The fire emulator/detector evaluator (FE/DE) is a computer-controlled flow tunnel used to re-create the environments surrounding detectors in the early...

  2. Fire Emulator/Detector Evaluator

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The fire emulator/detector evaluator (FE/DE) is a computer-controlled flow tunnel used to re-create the environments surrounding detectors in the early...

  3. Atomic scale engineering of HfO{sub 2}-based dielectrics for future DRAM applications

    Energy Technology Data Exchange (ETDEWEB)

    Dudek, Piotr

    2011-02-14

    Modern dielectrics in combination with appropriate metal electrodes have a great potential to solve many difficulties associated with continuing miniaturization process in the microelectronic industry. One significant branch of microelectronics incorporates dynamic random access memory (DRAM) market. The DRAM devices scaled for over 35 years starting from 4 kb density to several Gb nowadays. The scaling process led to the dielectric material thickness reduction, resulting in higher leakage current density, and as a consequence higher power consumption. As a possible solution for this problem, alternative dielectric materials with improved electrical and material science parameters were intensively studied by many research groups. The higher dielectric constant allows the use of physically thicker layers with high capacitance but strongly reduced leakage current density. This work focused on deposition and characterization of thin insulating layers. The material engineering process was based on Si cleanroom compatible HfO{sub 2} thin films deposited on TiN metal electrodes. A combined materials science and dielectric characterization study showed that Ba-added HfO{sub 2} (BaHfO{sub 3}) films and Ti-added BaHfO{sub 3} (BaHf{sub 0.5}Ti{sub 0.5}O{sub 3}) layers are promising candidates for future generation of state-of-the-art DRAMs. In especial a strong increase of the dielectric permittivity k was achieved for thin films of cubic BaHfO{sub 3} (k{proportional_to}38) and BaHf{sub 0.5}Ti{sub 0.5}O{sub 3} (k{proportional_to}90) with respect to monoclinic HfO{sub 2} (k{proportional_to}19). Meanwhile the CET values scaled down to 1 nm for BaHfO{sub 3} and {proportional_to}0.8 nm for BaHf{sub 0.5}Ti{sub 0.5}O{sub 3} with respect to HfO{sub 2} (CET=1.5 nm). The Hf{sup 4+} ions substitution in BaHfO{sub 3} by Ti{sup 4+} ions led to a significant decrease of thermal budget from 900 C for BaHfO{sub 3} to 700 C for BaHf{sub 0.5}Ti{sub 0.5}O{sub 3}. Future studies need to focus

  4. Evolution of continental crust and mantle heterogeneity: Evidence from Hf isotopes

    Science.gov (United States)

    Jonathan, Patchett P.; Kouvo, O.; Hedge, C.E.; Tatsumoto, M.

    1982-01-01

    We present initial 176Hf/177 Hf ratios for many samples of continental crust 3.7-0.3 Gy old. Results are based chiefly on zircons (1% Hf) and whole rocks: zircons are shown to be reliable carriers of essentially the initial Hf itself when properly chosen on the basis of U-Pb studies. Pre-3.0 Gy gneisses were apparently derived from an unfractionated mantle, but both depleted and undepleted mantle are evident as magma sources from 2.9 Gy to present. This mantle was sampled mainly from major crustal growth episodes 2.8, 1.8 and 0.7 Gy ago, all of which show gross heterogeneity of 176Hf/177Hf in magma sources from ??Hf=0 to +14, or about 60% of the variability of the present mantle. The approximate ??Hf=2??Nd relationship in ancient and modern igneous rocks shows that 176Lu/177Hf fractionates in general twice as much as 147Sm/144Nd in mantle melting processes. This allows an estimation of the relative value of the unknown bulk solid/liquid distribution coefficient for Hf. DLu/DHf=??? 2.3 holds for most mantle source regions. For garnet to be an important residual mantle phase, it must hold Hf strongly in order to preserve Hf-Nd isotopic relationships. The ancient Hf initials are consistent with only a small proportion of recycled older cratons in new continental crust, and with quasi-continuous, episodic growth of the continental crust with time. However, recycling of crust less than 150 My old cannot realistically be detected using Hf initials. The mantle shows clearly the general positive ??Hf resulting from a residual geochemical state at least back to 2.9 Gy ago, and seems to have repeatedly possessed a similar degree of heterogeneity, rather than a continuously-developing depletion. This is consistent with a complex dynamic disequilibrium model for the creation, maintenance and destruction of heterogeneity in the mantle. ?? 1981 Springer-Verlag.

  5. What Hf isotopes in zircon tell us about crust-mantle evolution

    Science.gov (United States)

    Iizuka, Tsuyoshi; Yamaguchi, Takao; Itano, Keita; Hibiya, Yuki; Suzuki, Kazue

    2017-03-01

    The 176Lu-176Hf radioactive decay system has been widely used to study planetary crust-mantle differentiation. Of considerable utility in this regard is zircon, a resistant mineral that can be precisely dated by the U-Pb chronometer and record its initial Hf isotope composition due to having low Lu/Hf. Here we review zircon U-Pb age and Hf isotopic data mainly obtained over the last two decades and discuss their contributions to our current understanding of crust-mantle evolution, with emphasis on the Lu-Hf isotope composition of the bulk silicate Earth (BSE), early differentiation of the silicate Earth, and the evolution of the continental crust over geologic history. Meteorite zircon encapsulates the most primitive Hf isotope composition of our solar system, which was used to identify chondritic meteorites best representative of the BSE (176Hf/177Hf = 0.282793 ± 0.000011; 176Lu/177Hf = 0.0338 ± 0.0001). Hadean-Eoarchean detrital zircons yield highly unradiogenic Hf isotope compositions relative to the BSE, providing evidence for the development of a geochemically enriched silicate reservoir as early as 4.5 Ga. By combining the Hf and O isotope systematics, we propose that the early enriched silicate reservoir has resided at depth within the Earth rather than near the surface and may represent a fractionated residuum of a magma ocean underlying the proto-crust, like urKREEP beneath the anorthositic crust on the Moon. Detrital zircons from world major rivers potentially provide the most robust Hf isotope record of the preserved granitoid crust on a continental scale, whereas mafic rocks with various emplacement ages offer an opportunity to trace the Hf isotope evolution of juvenile continental crust (from εHf[4.5 Ga] = 0 to εHf[present] = + 13). The river zircon data as compared to the juvenile crust composition highlight that the supercontinent cycle has controlled the evolution of the continental crust by regulating the rates of crustal generation and intra

  6. HEPS-BPIX, a single photon counting pixel detector with a high frame rate for the HEPS project

    Science.gov (United States)

    Wei, Wei; Zhang, Jie; Ning, Zhe; Lu, Yunpeng; Fan, Lei; Li, Huaishen; Jiang, Xiaoshan; Lan, Allan K.; Ouyang, Qun; Wang, Zheng; Zhu, Kejun; Chen, Yuanbo; Liu, Peng

    2016-11-01

    China's next generation light source, named the High Energy Photon Source (HEPS), is currently under construction. HEPS-BPIX (HEPS-Beijing PIXel) is a dedicated pixel readout chip that operates in single photon counting mode for X-ray applications in HEPS. Designed using CMOS 0.13 μm technology, the chip contains a matrix of 104×72 pixels. Each pixel measures 150 μm×150 μm and has a counting depth of 20 bits. A bump-bonded prototyping detector module with a 300-μm thick silicon sensor was tested in the beamline of Beijing Synchrotron Radiation Facility. A fast stream of X-ray images was demonstrated, and a frame rate of 1.2 kHz was proven, with a negligible dead time. The test results showed an equivalent noise charge of 115 e- rms after bump bonding and a threshold dispersion of 55 e- rms after calibration.

  7. Position sensitive solid state detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schnatterly, S.E.; Husk, D.

    1986-05-15

    Solid state detectors have been used for years as high quantum efficiency detectors for visible light. In this paper the use of PDA and CCD, solid state detectors, in the X-ray region will be discussed. In particular examples of data in the soft X-ray region are presented. Finally the use of phosphor coatings to enhance the sensitivity of solid state detectors is described.

  8. Radiation detectors laboratory; Laboratorio de detectores de radiacion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez J, F.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  9. ATLAS Detector : Performance and Upgrades

    CERN Document Server

    Oliveira Damazio, Denis; The ATLAS collaboration

    2016-01-01

    Describe the ATLAS detector and summarize most relevant and recent information about the detector performance in 2016 with LHC colliding bunches at sqrt(s)=13 TeV with luminosity above the nominal value. Describe the different upgrade phases previewed for the detector and main activities already ongoing.

  10. Characterizations of GEM detector prototype

    CERN Document Server

    INSPIRE-00522505; Rudra, Sharmili; Bhattacharya, P.; Sahoo, Sumanya Sekhar; Biswas, S.; Mohanty, B.; Nayak, T.K.; Sahu, P.K.; Sahu, S.

    2016-01-01

    At NISER-IoP detector laboratory an initiative is taken to build and test Gas Electron Multiplier (GEM) detectors for ALICE experiment. The optimisation of the gas flow rate and the long-term stability test of the GEM detector are performed. The method and test results are presented.

  11. Characterisations of GEM detector prototype

    Energy Technology Data Exchange (ETDEWEB)

    Patra, Rajendra Nath [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, West Bengal (India); Nanda, Amit [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Rudra, Sharmili [Department of Applied Physics, CU, 92, APC Road, Kolkata 700009, West Bengal (India); Bhattacharya, P.; Sahoo, Sumanya Sekhar [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Biswas, S., E-mail: saikat.ino@gmail.com [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Mohanty, B. [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Nayak, T.K. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, West Bengal (India); Sahu, P.K.; Sahu, S. [Institute of Physics, Sachivalaya Marg, P.O.: Sainik School, Bhubaneswar 751005, Odisha (India)

    2016-07-11

    At NISER-IoP detector laboratory an initiative is taken to build and test Gas Electron Multiplier (GEM) detectors for ALICE experiment. The optimisation of the gas flow rate and the long-term stability test of the GEM detector are performed. The method and test results are presented.

  12. Workshops on radiation imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sochinskii, N.V.; Sun, G.C.; Kostamo, P.; Silenas, A.; Saynatjoki, A.; Grant, J.; Owens, A.; Kozorezov, A.G.; Noschis, E.; Van Eijk, C.; Nagarkar, V.; Sekiya, H.; Pribat, D.; Campbell, M.; Lundgren, J.; Arques, M.; Gabrielli, A.; Padmore, H.; Maiorino, M.; Volpert, M.; Lebrun, F.; Van der Putten, S.; Pickford, A.; Barnsley, R.; Anton, M.E.G.; Mitschke, M.; Gros d' Aillon, E.; Frojdh, C.; Norlin, B.; Marchal, J.; Quattrocchi, M.; Stohr, U.; Bethke, K.; Bronnimann, C.H.; Pouvesle, J.M.; Hoheisel, M.; Clemens, J.C.; Gallin-Martel, M.L.; Bergamaschi, A.; Redondo-Fernandez, I.; Gal, O.; Kwiatowski, K.; Montesi, M.C.; Smith, K

    2005-07-01

    This document gathers the transparencies that were presented at the international workshop on radiation imaging detectors. 9 sessions were organized: 1) materials for detectors and detector structure, 2) front end electronics, 3) interconnected technologies, 4) space, fusion applications, 5) the physics of detection, 6) industrial applications, 7) synchrotron radiation, 8) X-ray sources, and 9) medical and other applications.

  13. Influence of Hf contents on interface state properties in a-HfInZnO thin-film transistors with SiNx/SiOx gate dielectrics

    Science.gov (United States)

    Choi, Hyun-Sik; Jeon, Sanghun; Kim, Hojung; Shin, Jaikwang; Kim, Changjung; Chung, U.-In

    2011-10-01

    We evaluated the interface properties of amorphous hafnium-indium-zinc-oxide (a-HIZO) thin-film transistors (TFTs) with respect to various Hf contents. To this end, the subthreshold swing and the low-frequency noise (LFN) of the a-HIZO TFTs were measured and compared. From LFNs providing more accurate information, we quantitatively analyzed the interface trap densities and found that they decrease with increasing Hf contents. Although the acceptor-like tail state densities in bulk channel increase with Hf contents, higher Hf contents show lower threshold voltage shift under bias stress, implying that reliability characteristics of a-HIZO TFTs are more sensitive to interface quality rather than bulk property.

  14. Distribution of p-process 174Hf in early solar system materials and the origin of nucleosynthetic Hf and W isotope anomalies in Ca-Al rich inclusions

    Science.gov (United States)

    Peters, Stefan T. M.; Münker, Carsten; Pfeifer, Markus; Elfers, Bo-Magnus; Sprung, Peter

    2017-02-01

    Some nuclides that were produced in supernovae are heterogeneously distributed between different meteoritic materials. In some cases these heterogeneities have been interpreted as the result of interaction between ejecta from a nearby supernova and the nascent solar system. Particularly in the case of the oldest objects that formed in the solar system - Ca-Al rich inclusions (CAIs) - this view is confirm the hypothesis that a nearby supernova event facilitated or even triggered solar system formation. We present Hf isotope data for bulk meteorites, terrestrial materials and CAIs, for the first time including the low-abundance isotope 174Hf (∼0.16%). This rare isotope was likely produced during explosive O/Ne shell burning in massive stars (i.e., the classical "p-process"), and therefore its abundance potentially provides a sensitive tracer for putative heterogeneities within the solar system that were introduced by supernova ejecta. For CAIs and one LL chondrite, also complementary W isotope data are reported for the same sample cuts. Once corrected for small neutron capture effects, different chondrite groups, eucrites, a silicate inclusion of a IAB iron meteorite, and terrestrial materials display homogeneous Hf isotope compositions including 174Hf. Hafnium-174 was thus uniformly distributed in the inner solar system when planetesimals formed at the system composition, and also variable r-process (or s-process) Hf and W contributions. Based on combined Hf and W isotope compositions, we show that CAIs sampled at least one component in which the proportion of r- and s-process derived Hf and W deviates from that of supernova ejecta. The Hf and W isotope anomalies in CAIs are therefore best explained by selective processing of presolar carrier phases prior to CAI formation, and not by a late injection of supernova materials. Likewise, other isotope anomalies in additional elements in CAIs relative to the bulk solar system may reflect the same process. The isotopic

  15. Air sensitivity of MoS2, MoSe2, MoTe2, HfS2, and HfSe2

    Science.gov (United States)

    Mirabelli, Gioele; McGeough, Conor; Schmidt, Michael; McCarthy, Eoin K.; Monaghan, Scott; Povey, Ian M.; McCarthy, Melissa; Gity, Farzan; Nagle, Roger; Hughes, Greg; Cafolla, Attilio; Hurley, Paul K.; Duffy, Ray

    2016-09-01

    A surface sensitivity study was performed on different transition-metal dichalcogenides (TMDs) under ambient conditions in order to understand which material is the most suitable for future device applications. Initially, Atomic Force Microscopy and Scanning Electron Microscopy studies were carried out over a period of 27 days on mechanically exfoliated flakes of 5 different TMDs, namely, MoS2, MoSe2, MoTe2, HfS2, and HfSe2. The most reactive were MoTe2 and HfSe2. HfSe2, in particular, showed surface protrusions after ambient exposure, reaching a height and width of approximately 60 nm after a single day. This study was later supplemented by Transmission Electron Microscopy (TEM) cross-sectional analysis, which showed hemispherical-shaped surface blisters that are amorphous in nature, approximately 180-240 nm tall and 420-540 nm wide, after 5 months of air exposure, as well as surface deformation in regions between these structures, related to surface oxidation. An X-ray photoelectron spectroscopy study of atmosphere exposed HfSe2 was conducted over various time scales, which indicated that the Hf undergoes a preferential reaction with oxygen as compared to the Se. Energy-Dispersive X-Ray Spectroscopy showed that the blisters are Se-rich; thus, it is theorised that HfO2 forms when the HfSe2 reacts in ambient, which in turn causes the Se atoms to be aggregated at the surface in the form of blisters. Overall, it is evident that air contact drastically affects the structural properties of TMD materials. This issue poses one of the biggest challenges for future TMD-based devices and technologies.

  16. Detector and System Developments for LHC Detector Upgrades

    CERN Document Server

    Mandelli, Beatrice; Guida, Roberto; Rohne, Ole; Stapnes, Steinar

    2015-05-12

    The future Large Hadron Collider (LHC) Physics program and the consequent improvement of the LHC accelerator performance set important challenges to all detector systems. This PhD thesis delineates the studies and strategies adopted to improve two different types of detectors: the replacement of precision trackers with ever increasingly performing silicon detectors, and the improvement of large gaseous detector systems by optimizing their gas mixtures and operation modes. Within the LHC tracker upgrade programs, the ATLAS Insertable B-layer (IBL) is the first major upgrade of a silicon-pixel detector. Indeed the overall ATLAS Pixel Detector performance is expected to degrade with the increase of luminosity and the IBL will recover the performance by adding a fourth innermost layer. The IBL Detector makes use of new pixel and front-end electronics technologies as well as a novel thermal management approach and light support and service structures. These innovations required complex developments and Quality Ass...

  17. Cooled CdZnTe detectors for X-ray astronomy

    CERN Document Server

    Bale, G; Seller, P; Lowe, B

    1999-01-01

    Recent results combining thermoelectrically cooled CdZnTe detectors with a low-noise Pentafet preamplifier are presented. Cooling between -30 deg. C and -40 deg. C reduces the leakage current of the detectors and allows the use of a pulsed reset preamplifier and long shaping times, significantly improving the energy resolution. Mn K subalpha X-rays at 5.9 keV have been observed with a resolution of less than 280 eV FWHM and a peak to background of more than 200:1. The Fano factor of the material has been estimated at 0.11+-0.012 at -40 deg. C. The detector requirement for X-ray astronomy will be a photon-counting imaging spectrometer. A 16x16 element, bump bonded pixel detector is described and results from a prototype silicon array presented. The detector is constructed with ASIC amplifiers with a system noise of <25 electrons rms and should give an energy resolution comparable to the Pentafet results presented here.

  18. Flat-Field Calibration of CCD Detector for Long TraceProfilers

    Energy Technology Data Exchange (ETDEWEB)

    Kirschman, Jonathan L.; Domning, Edward E.; Franck, Keith D.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Morrison,Gregory Y.; Smith, Brian V.; Warwick, Tony; Yashchuk, Valeriy V.

    2007-07-31

    The next generation of synchrotrons and free electron lasersrequires x-ray optical systems with extremely high-performance,generally, of diffraction limited quality. Fabrication and use of suchoptics requires highly accurate metrology. In the present paper, wediscuss a way to improve the performance of the Long Trace Profiler(LTP), a slope measuring instrument widely used at synchrotron facilitiesto characterize x-ray optics at high-spatial-wavelengths fromapproximately 2 mm to 1 m. One of the major sources of LTP systematicerror is the detector. For optimal functionality, the detector has topossess the smallest possible pixel size/spacing, a fast method ofshuttering, and minimal non-uniformity of pixel-to-pixel photoresponse.While the first two requirements are determined by choice of detector,the non-uniformity of photoresponse of typical detectors such as CCDcameras is around 2-3 percent. We describe a flat-field calibration setupspecially developed for calibration of CCD camera photo-response and darkcurrent with an accuracy of better than 0.5 percent. Such accuracy isadequate for use of a camera as a detector for an LTP with performance of~;0.1 microradian (rms). We also present the design details of thecalibration system and results of calibration of a DALSA CCD camera usedfor upgrading our LTP-II instrument at the ALS Optical MetrologyLaboratory.

  19. Design and Fabrication of the KID-Based Light Detectors of CALDER

    Science.gov (United States)

    Colantoni, I.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D'Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

    2016-07-01

    The goal of the Cryogenic wide-Area Light Detectors with Excellent Resolution project is the development of light detectors with large active area and noise energy resolution smaller than 20 eV RMS using phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the design and the fabrication process, starting from the silicon wafer arriving to the single chip. The Al thin films (40 nm) are evaporated on high-quality, high-resistivity (>10 k Ω cm) Si(100) substrates using an electron beam evaporator in a high-vacuum chamber. Detectors are patterned in direct-write mode, using electron beam lithography , positive tone resist poly-methyl methacrylate and lift-off process. Finally the wafer is diced into 20 × 20 mm^2 chips and assembled in a holder OFHC copper (oxygen-free high conductivity) using PTFE supports.

  20. High sensitivity phonon-mediated kinetic inductance detector with combined amplitude and phase read-out

    CERN Document Server

    Bellini, F; Casali, N; Castellano, M G; Colantoni, I; Cosmelli, C; Cruciani, A; D'Addabbo, A; Di Domizio, S; Martinez, M; Tomei, C; Vignati, M

    2016-01-01

    The development of wide-area cryogenic light detectors with good energy resolution is one of the priorities of next generation bolometric experiments searching for rare interactions, as the simultaneous read-out of the light and heat signals enables background suppression through particle identification. Among the proposed technological approaches for the phonon sensor, the naturally-multiplexed Kinetic Inductance Detectors (KIDs) stand out for their excellent intrinsic energy resolution and reproducibility. To satisfy the large surface requirement (several cm$^2$) KIDs are deposited on an insulating substrate that converts the impinging photons into phonons.A fraction of phonons is absorbed by the KID, producing a signal proportional to the energy of the original photons. The potential of this technique was proved by the CALDER project, that reached a baseline resolution of 154$\\pm$7 eV RMS by sampling a 2$\\times$2 cm$^2$ Silicon substrate with 4 Aluminum KIDs. In this paper we present a prototype of Aluminu...

  1. EURObservational Research Programme : The Heart Failure Pilot Survey (ESC-HF Pilot)

    NARCIS (Netherlands)

    Maggioni, Aldo P.; Dahlstrom, Ulf; Filippatos, Gerasimos; Chioncel, Ovidiu; Crespo Leiro, Marisa; Drozdz, Jaroslaw; Fruhwald, Friedrich; Gullestad, Lars; Logeart, Damien; Metra, Marco; Parissis, John; Persson, Hans; Ponikowski, Piotr; Rauchhaus, Mathias; Voors, Adriaan A.; Nielsen, Olav Wendelboe; Zannad, Faiez; Tavazzi, Luigi

    2010-01-01

    The primary objective of the new ESC-HF Pilot Survey was to describe the clinical epidemiology of outpatients and inpatients with heart failure (HF) and the diagnostic/therapeutic processes applied across 12 participating European countries. This pilot study was specifically aimed at validating the

  2. EURObservational Research Programme: the Heart Failure Pilot Survey (ESC-HF Pilot)

    DEFF Research Database (Denmark)

    Maggioni, Aldo P; Dahlström, Ulf; Filippatos, Gerasimos;

    2010-01-01

    The primary objective of the new ESC-HF Pilot Survey was to describe the clinical epidemiology of outpatients and inpatients with heart failure (HF) and the diagnostic/therapeutic processes applied across 12 participating European countries. This pilot study was specifically aimed at validating...... the structure, performance, and quality of the data set, for continuing the survey into a permanent registry....

  3. Effects of sol aging on resistive switching behaviors of HfO{sub x} resistive memories

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Chih-Chieh, E-mail: cchsu@yuntech.edu.tw [Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Department of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Graduate School of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting [Graduate School of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China)

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfO{sub x} resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfO{sub x} surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfO{sub x} film can be avoided. Under this circumstance, effects of sol aging time on the HfO{sub x} films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfO{sub x} RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfO{sub x} layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfO{sub x} film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfO{sub x} resistive switching characteristic induced by sol aging.

  4. The effects of composition on mechanical properties of W-4Re-Hf-C alloys

    Science.gov (United States)

    Witzke, W. R.

    1974-01-01

    Studies were made of the effects of alloy composition on the mechanical behavior of as-worked W-4Re-Hf-C alloys containing up to about 0.8 mol % Hfc. Extracted second-phase particles were analyzed and related to alloy composition and creep strength. While strengthening is attributed to HfC particles, the presence of excess hafnium or carbon (above the calculated amounts for stoichiometric HfC) in swaged W-4Re-Hf-C alloys generally causes a reduction of the high-temperature (1930 C) tensile strength; maximum creep strength is, however, indicated for alloys with a slight (about 0.05 to 0.1 at. %) excess of hafnium. Particle strengthening is reduced by WC in solid solution with HfC for allow compositions with an excess of carbon. The low-temperature ductility of worked W-4Re-Hf-C alloys appears to be far more dependent on the amount of excess C or Hf present than on the HfC particle content in the range studies.

  5. First results on the sorption behaviour of Rutherfordium from HCl/HF containing aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, D.; Nitsche, H. [Technische Univ. Dresden (Germany); Taut, S. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany); Jost, D.T.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Yakushev, A.B.; Buklanov, G.V.; Domanov, V.P.; Lien Din Thi [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Kubica, B.; Misiak, R.; Szeglowski, Z. [NINP Cracow (Poland)

    1997-09-01

    Rutherfordium shows strong sorption on the cation exchanger DOWEX 50x8 at a concentration of 0.1 M HCl/10{sup -2} M HF. This shows that Rf behaves under these conditions differently from Hf and Zr and more like Th under these conditions. (author) 1 fig., 5 refs.

  6. Effects of sol aging on resistive switching behaviors of HfOx resistive memories

    Science.gov (United States)

    Hsu, Chih-Chieh; Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfOx resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfOx surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfOx film can be avoided. Under this circumstance, effects of sol aging time on the HfOx films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfOx RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfOx layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfOx film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfOx resistive switching characteristic induced by sol aging.

  7. The Modulation of Ionospheric Alfven Resonator on Heating HF Waves and the Doppler Effect

    Institute of Scientific and Technical Information of China (English)

    NiBin-bin; ZhaoZheng-yu; XieShu-guo

    2003-01-01

    The propagation of HF waves in IAR can produce many nonlinear effects, including the modulation effect of IAR on HF waves and the Doppler effect. To start with the dependence of the ionospheric electron temperature varia-tions on the Alfven resonant field, We discuss the mechanism of the modulation effect and lucubrate possible reasons for the Doppler effect. The results show that the Alfven resonant field can have an observable modulation effect on HF waves while its mechanism is quite different from that of Schumann resonant field on HF waves. The depth of modulation of IAR on HF waves has a quasi-quadratic relation with the Alfven field, which directly inspires the formation of cross-spectrum between ULF waves and HF waves and results in spectral peaks at some gyro-frequencies of IAR. With respect to the Doppler effect during the propagation of HF waves in IAR, it is mainly caused by the motion of the high-speed flyer and the drifting electrons and the frequency shift from the phase vari-ation of the reflected waves can be neglected when the frequency of HF incident wave is high enough.

  8. New PWM method and commutation strategy for HF-link converters for fuel cells and photovoltaics

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a new PWM method and commutation strategy for HF-link converters, which leads to safe commutation of the load current in the output bidirectional bridge. The proposed implementation is independent of the particular HF-link converter topology and bidirectional switch selection...

  9. 47 CFR 73.758 - System specifications for digitally modulated emissions in the HF broadcasting service.

    Science.gov (United States)

    2010-10-01

    ... emissions in the HF broadcasting service. 73.758 Section 73.758 Telecommunication FEDERAL COMMUNICATIONS... § 73.758 System specifications for digitally modulated emissions in the HF broadcasting service. (a... digital audio broadcasting and datacasting are authorized. The RF requirements for the DRM system...

  10. Computed tomographic coronary angiography for patients with heart failure (CTA-HF): a randomized controlled trial (IMAGE HF Project 1-C).

    Science.gov (United States)

    Chow, Benjamin J W; Green, Rachel E; Coyle, Doug; Laine, Mika; Hanninen, Helena; Leskinen, Hanna; Rajda, Miroslav; Larose, Eric; Hartikainen, Juha; Hedman, Marja; Mielniczuk, Lisa; O'Meara, Eileen; deKemp, Robert A; Klein, Ran; Paterson, Ian; White, James A; Yla-Herttuala, Seppo; Leber, Alex; Tandon, Vikas; Lee, Ting; Al-Hesayen, Abdul; Hessian, Renee; Dowsley, Taylor; Kass, Malek; Kelly, Cathy; Garrard, Linda; Tardif, Jean-Claude; Knuuti, Juhani; Beanlands, Rob S; Wells, George A

    2013-12-26

    The prevalence of heart failure (HF) is rising in industrialized and developing countries. Though invasive coronary angiography (ICA) remains the gold standard for anatomical assessment of coronary artery disease in HF patients, alternatives are being sought. Computed tomographic coronary angiography (CTA) has emerged as an accurate non-invasive diagnostic tool for coronary artery disease (CAD) and has been demonstrated to have prognostic value. Whether or not CTA can be used in HF patients is unknown. Acknowledging the aging population, the growing prevalence of HF and the increasing financial burden of healthcare, we need to identify non-invasive diagnostic tests that are available, safe, accurate and cost-effective. The proposed study aims to provide insight into the efficacy of CTA in HF patients. A multicenter randomized controlled trial will enroll 250 HF patients requiring coronary anatomical definition. Enrolled patients will be randomized to either CTA or ICA (n = 125 per group) as the first test to define coronary anatomy. The primary outcomes will be collected to determine downstream resource utilization. Secondary outcomes will include the composite clinical events and major adverse cardiac events. In addition, the accuracy of CTA for detecting coronary anatomy and obstruction will be assessed in patients who subsequently undergo both CTA and ICA. It is expected that CTA will be a more cost-effective strategy for diagnosis: yielding similar outcomes with fewer procedural risks and improved resource utilization. ClinicalTrials.gov, NCT01283659. Team grant #CIF 99470.

  11. Front-end ASIC for pixilated wide bandgap detectors

    Science.gov (United States)

    Vernon, Emerson; de Geronimo, Gianluigi; Fried, Jack; Herman, Cedric; Zhang, Feng; He, Zhong

    2009-08-01

    A CMOS application specific integrated circuit (ASIC) was developed for 3D Position Sensitive Detectors (PSD). The preamplifiers were optimized for pixellated Cadmium-Zinc-Telluride (CZT) Mercuric-Iodide (HgI2) and Thallium Bromide (TlBr) sensors. The ASIC responds to an ionizing event in the sensor by measuring both amplitude and timing in the pertinent anode and cathode channels. Each channel is sensitive to events and transients of positive or negative polarity and performs low-noise charge amplification, high-order shaping, peak and timing detection along with analog storage and multiplexing. Three methodologies are implemented to perform timing measurement in the cathode channel. Multiple sparse modes are available for the readout of channel data. The ASIC integrates 130 channels in an area of 12 x 9 mm2 and dissipates ~330 mW. With a CZT detector connected and biased, an electronic resolution of ~200 e- rms for charges up to 100 fC was measured. Spectral data from the University of Michigan revealed a cumulative single-pixel resolution of ~0.55 % FWHM at 662 KeV.

  12. Future liquid Argon detectors

    CERN Document Server

    Rubbia, A

    2013-01-01

    The Liquid Argon Time Projection Chamber offers an innovative technology for a new class of massive detectors for rare-event detection. It is a precise tracking device that allows three-dimensional spatial reconstruction with mm-scale precision of the morphology of ionizing tracks with the imaging quality of a "bubble chamber", provides $dE/dx$ information with high sampling rate, and acts as high-resolution calorimeter for contained events. First proposed in 1977 and after a long maturing process, its holds today the potentialities of opening new physics opportunities by providing excellent tracking and calorimetry performance at the relevant multi-kton mass scales, outperforming other techniques. In this paper, we review future liquid argon detectors presently being discussed by the neutrino physics community.

  13. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  14. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    Since September, the muon alignment system shifted from a mode of hardware installation and commissioning to operation and data taking. All three optical subsystems (Barrel, Endcap and Link alignment) have recorded data before, during and after CRAFT, at different magnetic fields and during ramps of the magnet. This first data taking experience has several interesting goals: •    study detector deformations and movements under the influence of the huge magnetic forces; •    study the stability of detector structures and of the alignment system over long periods, •    study geometry reproducibility at equal fields (specially at 0T and 3.8T); •    reconstruct B=0T geometry and compare to nominal/survey geometries; •    reconstruct B=3.8T geometry and provide DT and CSC alignment records for CMSSW. However, the main goal is to recons...

  15. The LUCID detector

    CERN Document Server

    Lasagni Manghi, Federico; The ATLAS collaboration

    2015-01-01

    Starting from 2015 LHC is performing a new run, at higher center of mass energy (13 TeV) and with 25 ns bunch-spacing. The ATLAS luminosity monitor LUCID has been completely renewed, both on detector design and in the electronics, in order to cope with the new running conditions. The new detector electronics is presented, featuring a new read-out board (LUCROD), for signal acquisition and digitization, PMT-charge integration and single-side luminosity measurements, and the revisited LUMAT board for side-A-side-C combination. The contribution covers the new boards design, the firmware and software developments, the implementation of luminosity algorithms, the optical communication between boards and the integration into the ATLAS TDAQ system.

  16. UA1 central detector

    CERN Multimedia

    The UA1 central detector was crucial to understanding the complex topology of proton-antiproton events. It played a most important role in identifying a handful of Ws and Zs among billions of collisions. The detector was a 6-chamber cylindrical assembly 5.8 m long and 2.3 m in diameter, the largest imaging drift chamber of its day. It recorded the tracks of charged particles curving in a 0.7 Tesla magnetic field, measuring their momentum, the sign of their electric charge and their rate of energy loss (dE/dx). Atoms in the argon-ethane gas mixture filling the chambers were ionised by the passage of charged particles. The electrons which were released drifted along an electric field shaped by field wires and were collected on sense wires. The geometrical arrangement of the 17000 field wires and 6125 sense wires allowed a spectacular 3-D interactive display of reconstructed physics events to be produced.

  17. Metrology with Unknown Detectors.

    Science.gov (United States)

    Altorio, Matteo; Genoni, Marco G; Somma, Fabrizia; Barbieri, Marco

    2016-03-11

    The best possible precision is one of the key figures in metrology, but this is established by the exact response of the detection apparatus, which is often unknown. There exist techniques for detector characterization that have been introduced in the context of quantum technologies but apply as well for ordinary classical coherence; these techniques, though, rely on intense data processing. Here, we show that one can make use of the simpler approach of data fitting patterns in order to obtain an estimate of the Cramér-Rao bound allowed by an unknown detector, and we present applications in polarimetry. Further, we show how this formalism provides a useful calculation tool in an estimation problem involving a continuous-variable quantum state, i.e., a quantum harmonic oscillator.

  18. Aerogel for FARICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Barnyakov, A.Yu. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Barnyakov, M.Yu. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, Karl Marks 20, Novosibirsk 630073 (Russian Federation); Bobrovnikov, V.S.; Buzykaev, A.R.; Gulevich, V.V. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Danilyuk, A.F. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation); Kononov, S.A.; Kravchenko, E.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova 2, Novosibirsk 630090 (Russian Federation); Kuyanov, I.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Lopatin, S.A. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation); Onuchin, A.P.; Ovtin, I.V.; Podgornov, N.A. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, Karl Marks 20, Novosibirsk 630073 (Russian Federation); Porosev, V.V. [Budker Institute of Nuclear Physics, Lavrentieva 11, Novosibirsk 630090 (Russian Federation); Predein, A.Yu.; Protsenko, R.S. [Boreskov Institute of Catalysis, Lavrentieva 5, Novosibirsk 630090 (Russian Federation)

    2014-12-01

    We present our current experience in preparation of focusing aerogels for the Focusing Aerogel RICH detector. Multilayer focusing aerogel tiles have been produced in Novosibirsk by a collaboration of the Budker Institute of Nuclear Physics and Boreskov Institute of Catalysis since 2004. We have obtained 2–3–4-layer blocks with the thickness of 30–45 mm. In 2012, the first samples of focusing blocks with continuous density (refractive index) gradient along thickness were produced. This technology can significantly reduce the contribution from the geometric factor of the radiator thickness to the resolution of the measured Cherenkov angle in the FARICH detector. The special installation was used for automatic control of reagents ratio during the synthesis process. The first samples were tested using the digital radiography method and on the electron beam with the FARICH prototype.

  19. Metrology with Unknown Detectors

    CERN Document Server

    Altorio, Matteo; Somma, Fabrizia; Barbieri, Marco

    2015-01-01

    The best possible precision is one of the key figures in metrology, but this is established by the exact response of the detection apparatus, which is often unknown. There exist techniques for detector characterisation, that have been introduced in the context of quantum technologies, but apply as well for ordinary classical coherence; these techniques, though, rely on intense data processing. Here we show that one can make use of the simpler approach of data fitting patterns in order to obtain an estimate of the Cram\\'er-Rao bound allowed by an unknown detector, and present applications in polarimetry. Further, we show how this formalism provide a useful calculation tool in an estimation problem involving a continuous-variable quantum state, i.e. a quantum harmonic oscillator.

  20. Radiation damage in silicon detectors

    CERN Document Server

    Lindström, G

    2003-01-01

    Radiation damage effects in silicon detectors under severe hadron and gamma-irradiation are surveyed, focusing on bulk effects. Both macroscopic detector properties (reverse current, depletion voltage and charge collection) as also the underlying microscopic defect generation are covered. Basic results are taken from the work done in the CERN-RD48 (ROSE) collaboration updated by results of recent work. Preliminary studies on the use of dimerized float zone and Czochralski silicon as detector material show possible benefits. An essential progress in the understanding of the radiation-induced detector deterioration had recently been achieved in gamma irradiation, directly correlating defect analysis data with the macroscopic detector performance.

  1. Detectors for the space telescope

    Science.gov (United States)

    Kelsall, T.

    1978-01-01

    This review of Space Telescope (ST) detectors is divided into two parts. The first part gives short summaries of detector programs carried out during the final planning stage (Phase B) of the ST and discusses such detectors as Photicon, the MAMA detectors, the CODACON, the University of Maryland ICCD, the Goddard Space Flight Center ICCD, and the 70 mm SEC TV sensor. The second part describes the detectors selected for the first ST flight, including the wide field/planetary camera, the faint object and high resolution spectrographs, and the high speed photometer.

  2. Signal processing technique for randomly discontinuous spectra HF radar waveforms

    Institute of Scientific and Technical Information of China (English)

    张东坡; 刘兴钊

    2004-01-01

    A major problem with all high frequency (HF) radars is a relatively poor range resolution available due to many interference sources. To avoid the interferences in frequency domain and operate with wideband, the randomly discontinuous spectra (RDS) signal is employed. However, it results in high range sidelobes when matching the reflected echo, which is much more difficult for target detection. A new signal processing technique that is radically different from the conventional technique to lower range sidelobes is introduced. This method is based on suppressing the selfclutter of the radar range ambiguity function (AF) by mismatched filtering. An effective algorithm is adopted to solve the filter coefficients. Simulation results show that the peak sidelobe level can be reduced to -30dB and the achievable system bandwidth is about 400KHz. The technique is adaptable to practical radar systems and applicable for other realtime signal processing.

  3. Modification of polarization filtering technique in HF ground wave radar

    Institute of Scientific and Technical Information of China (English)

    Zhang Guoyi; Tan Zhongji; Wang Jiantao

    2006-01-01

    The polarization filter using three orthogonal linear polarization antennas can suppress more disturbances than the polarization filter using two orthogonal linear polarization antennas in HF ground wave radar. But the algorithm of the threedimension filter is relatively complicated and not suitable for real-time processing. It can't use linear and nonlinear polarization vector translation technique directly. A modified polarization filter which is simple and has same suppressing ability as the three-dimension polarization filter is given. It only has half parameters of the primary one. Some problems about estimation of polarization parameters and selection of disturbances are discussed. A method of holding the phase of radar backscatter signal constantly is put forward so that unstationary disturbance signal can be processed.

  4. Toward an european Med HF-radar coastal monitoring

    Science.gov (United States)

    Molcard, A.; Fraunie, P.

    2010-12-01

    The monitoring of coastal areas through HF radar is developping in the european Mediterranean coasts, through national and international projects. Surface current maps may be used for process studies, forecast correction through assimilation, or for practical applications in transport studies (jellyfish, oil-spill, search-and-rescue operations). Results of radar campaigns in the North-western Mediterranean (evidence of mesoscale eddy in the Gulf of Lions and identification of dynamical structures by FSLE in the Ligurian Sea) are shown, as well as techniques for current reconstruction using a single site. A new inter-regional european project started in summer 2010, regrouping 5 countries for an integrated oil-spill coastal awarness network is presented.

  5. Biological detector and method

    Energy Technology Data Exchange (ETDEWEB)

    Sillerud, Laurel; Alam, Todd M.; McDowell, Andrew F.

    2015-11-24

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  6. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2014-04-15

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  7. The AMANDA Neutrino Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wischnewski, R.; Andres, E.; Askebjer, P.; Barwick, S.; Bay, R.; Bergstrom, L.; Biron, A.; Booth, J.; Botner, O.; Bouchta, A.; Carius, S.; Carlson, M.; Chinowsky, W.; Chirkin, D.; Cowen, D.; Costa, C.; Dalberg,E.; Deyoung, T.; Edsjo, J.; Ekstrom, P.; Goobar, A.; Gray, L.; Hallgren,A.; Halzen, F.; Hardtke, R.; He, Y.; Hill, G.; Hulth, P.; Hundertmark,S.; Jacobsen, J.; Kandhadai, V.; Karle, A.; Kim, J.; Leich, H.; Leuthold,M.; Lindahl, P.; Liss, T.; Liubarsky, I.; Loaiza, P.; Lowder, D.; Marciniewski, P.; Miller, T.; Miocinovic, P.; Mock, P.; Morse, R.; Newcomer, M.; Niessen, P.; Nygren, D.; de, los, Heros, CP.; Porrata, R.; Price, P.; Przybylski, G.; Rhode, W.; Richter, S.; Rodriguez, J.; Romenesko, P.; Ross, D.; Rubinstein, H.; Schmidt, T.; Schneider, E.; Schwarz, R.; Schwendicke, U.; Smoot, G.; Solarz, M.; Sorin, V.; Spiering,C.; Steffen, P.; Stokstad, R.; Streicher, O.; Thollander, L.; Thon, T.; Tilav, S.; Walck, C.; Wiebusch, C.; Woschnagg, K.; Wu, W.; Yodh, G.; Young, S.

    1999-08-23

    The first stage of the AMANDA High Energy Neutrino Detectorat the South Pole, the 302 PMT array AMANDA-B with an expected effectivearea for TeV neutrinos of similar to 10(4) m(2), has been taking datasince 1997. Progress with calibration, investigation of ice properties,as well as muon and neutrino data analysis are described. The next stage20-string detector AMANDA-II with similar to 800 PMTs will be completedin spring 2000.

  8. The ALEPH detector

    CERN Document Server

    1988-01-01

    For detecting the direction and momenta of charged particles with extreme accuracy, the ALEPH detector had at its core a time projection chamber, for years the world's largest. In the foreground from the left, Jacques Lefrancois, Jack Steinberger, Lorenzo Foa and Pierre Lazeyras. ALEPH was an experiment on the LEP accelerator, which studied high-energy collisions between electrons and positrons from 1989 to 2000.

  9. LHCb velo detector

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    Photo 01 : L. to r.: D. Malinon, Summer Student, J. Libby, Fellow, J. Harvey, Head of CERN LHCb group, D. Schlatter, Head of the EP Division in front of the LHCb velo detector test beam (on the right). Photo 02 : L. to r.: J. Harvey, D. Schlatter, W. Riegler (staff), H.J. Hilke, LHCb Technical Coordinator in front of the muon chamber test beam

  10. Development of Portable Detectors

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-12-01

    The purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC (the “Contractor”) and Sense Holdings, Inc. (the “Participant”) was for the development of hand-held detectors with high sensitivity and selectivity for the detection of explosives, toxic industrial chemicals and materials, and other materials of interest for security applications. The two parties built a series of demonstration and prototype handheld sensors based upon micoelectromechanical systems (MEMS) with electronic readout.

  11. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2013-02-26

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  12. Telemonitoring Adherence to Medications in Heart Failure Patients (TEAM-HF): A Pilot Randomized Clinical Trial.

    Science.gov (United States)

    Gallagher, Benjamin D; Moise, Nathalie; Haerizadeh, Mytra; Ye, Siqin; Medina, Vivian; Kronish, Ian M

    2017-04-01

    Medication nonadherence contributes to hospitalizations in recently discharged patients with heart failure (HF). We aimed to test the feasibility of telemonitoring medication adherence in patients with HF. We randomized 40 patients (1:1) hospitalized for HF to 30 days of loop diuretic adherence monitoring with telephonic support or to passive adherence monitoring alone. Eighty-three percent of eligible patients agreed to participate. The median age of patients was 64 years, 25% were female, and 45% were Hispanic. Overall, 67% of patients were nonadherent (percentage of days that the correct number of doses were taken telemonitoring was acceptable to most patients with HF. Diuretic nonadherence was common even when patients knew they were being monitored. Future studies should assess whether adherence telemonitoring can improve adherence and reduce readmissions among patients with HF. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. The electronic structure of HfF5- and WF5-

    Science.gov (United States)

    Chen, Hongshan; Andersson, Pontus; Lindahl, Anton O.; Hanstorp, Dag

    2011-08-01

    The electronic structure of HfF5-, WF5- and the related species HfF n and WF n is studied using ab initio methods. Computation reveals that the hafnium fluorides are much more stable than the corresponding tungsten fluorides. The detachment energy of HfF5- is 8.8 eV, whereas the corresponding quantity of WF5- is only 3.9 eV. These results show that WF5- can be photodetached while HfF5- is unaffected, and so it is possible by using photodetachment to suppress the interfering isobar 182W in the ion beam of 182Hf. Such information is the precondition for the successful implementation of a future photodetachment process in Accelerator Mass Spectrometry.

  14. Effect of hydrofluoric acid (HF) concentration to pores size diameter of silicon membrane.

    Science.gov (United States)

    Burham, Norhafizah; Hamzah, Azrul Azlan; Majlis, Burhanuddin Yeop

    2014-01-01

    This paper studies parameters which affect the pore size diameter of a silicon membrane. Electrochemical etching is performed in characterise the parameter involved in this process. The parameter has been studied is volume ratio of hydrofluoric acid (HF) and ethanol as an electrolyte aqueous for electrochemical etch. This electrolyte aqueous solution has been mixed between HF and ethanol with volume ratio 3:7, 5:5, 7:3 and 9:1. As a result, the higher volume of HF in this electrolyte gives the smallest pore size diameter compared to the lower volume of HF. These samples have been dipped into HF and ethanol electrolyte aqueous with supplied 25 mA/cm2 current density for 20, 30, 40, and 50 minutes. The samples will inspect under Scanning Electron Microscope (SEM) to execute the pore formations on silicon membrane surface.

  15. Suspended HfO{sub 2} photonic crystal slab on III-nitride/Si platform

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yongjin; Feng, Jiao; Cao, Ziping; Zhu, Hongbo [Nanjing University of Posts and Telecommunications, Grueenberg Research Centre, Nanjing, Jiang-Su (China)

    2014-06-15

    We present here the fabrication of suspended hafnium oxide (HfO{sub 2}) photonic crystal slab on a III-nitride/Si platform. The calculations are performed to model the suspended HfO{sub 2} photonic crystal slab. Aluminum nitride (AlN) film is employed as the sacrificial layer to form air gap. Photonic crystal patterns are defined by electron beam lithography and transferred into HfO{sub 2} film, and suspended HfO{sub 2} photonic crystal slab is achieved on a III-nitride/Si platform through wet-etching of AlN layer in the alkaline solution. The method is promising for the fabrication of suspended HfO{sub 2} nanostructures incorporating into a III-nitride/Si platform, or acting as the template for epitaxial growth of III-nitride materials. (orig.)

  16. Crystal structure of Si-doped HfO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Lili [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); School of Information Science and Technology, Northwest University, Xi' an 710127 (China); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Nelson, Matthew; Fancher, Chris M. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Aldridge, Henry [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Iamsasri, Thanakorn; Forrester, Jennifer S.; Jones, Jacob L., E-mail: jacobjones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Nishida, Toshikazu [Department of Electrical and Computer Engineering, University of Florida, Gainesville, Florida 32611 (United States); Moghaddam, Saeed [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2014-01-21

    Si-doped HfO{sub 2} was prepared by solid state synthesis of the starting oxides. Using Rietveld refinement of high resolution X-ray diffraction patterns, a substitutional limit of Si in HfO{sub 2} was determined as less than 9 at. %. A second phase was identified as Cristobalite (SiO{sub 2}) rather than HfSiO{sub 4}, the latter of which would be expected from existing SiO{sub 2}-HfO{sub 2} phase diagrams. Crystallographic refinement with increased Si-dopant concentration in monoclinic HfO{sub 2} shows that c/b increases, while β decreases. The spontaneous strain, which characterizes the ferroelastic distortion of the unit cell, was calculated and shown to decrease with increasing Si substitution.

  17. Tsunami Arrival Detection with High Frequency (HF Radar

    Directory of Open Access Journals (Sweden)

    Donald Barrick

    2012-05-01

    Full Text Available Quantitative real-time observations of a tsunami have been limited to deep-water, pressure-sensor observations of changes in the sea surface elevation and observations of sea level fluctuations at the coast, which are essentially point measurements. Constrained by these data, models have been used for predictions and warning of the arrival of a tsunami, but to date no system exists for local detection of an actual incoming wave with a significant warning capability. Networks of coastal high frequency (HF-radars are now routinely observing surface currents in many countries. We report here on an empirical method for the detection of the initial arrival of a tsunami, and demonstrate its use with results from data measured by fourteen HF radar sites in Japan and USA following the magnitude 9.0 earthquake off Sendai, Japan, on 11 March 2011. The distance offshore at which the tsunami can be detected, and hence the warning time provided, depends on the bathymetry: the wider the shallow continental shelf, the greater this time. We compare arrival times at the radars with those measured by neighboring tide gauges. Arrival times measured by the radars preceded those at neighboring tide gauges by an average of 19 min (Japan and 15 min (USA The initial water-height increase due to the tsunami as measured by the tide gauges was moderate, ranging from 0.3 to 2 m. Thus it appears possible to detect even moderate tsunamis using this method. Larger tsunamis could obviously be detected further from the coast. We find that tsunami arrival within the radar coverage area can be announced 8 min (i.e., twice the radar spectral time resolution after its first appearance. This can provide advance warning of the tsunami approach to the coastline locations.

  18. New Adaptive Data Transmission Scheme Over HF Radio

    Directory of Open Access Journals (Sweden)

    Adil H. Ahmad

    2008-01-01

    Full Text Available Acceptable Bit Error rate can be maintained by adapting some of the design parameters such as modulation, symbol rate, constellation size, and transmit power according to the channel state.An estimate of HF propagation effects can be used to design an adaptive data transmission system over HF link. The proposed system combines the well known Automatic Link Establishment (ALE together with variable rate transmission system. The standard ALE is modified to suite the required goal of selecting the best carrier frequency (channel for a given transmission. This is based on measuring SINAD (Signal plus Noise plus Distortion to Noise plus Distortion, RSL (Received Signal Level, multipath phase distortion and BER (Bit Error Rate for each channel in the frequency list. Channel condition evaluation is done by two arrangements. In the first an FFT analysis is used where a pilot signal is transmitted over the channel, while the data itself is used in the second arrangement. Passive channel assessment is used to avoid bad channels hence limiting the frequency pool size to be used in the point to point communication and the time required for scanning and linking. An exchange of channel information between the transmitting and receiving stations is considered to select the modulation scheme for transmission. Mainly MPSK and MFSK are considered with different levels giving different data rate according to the channel condition. The results of the computer simulation have shown that when transmitting at a fixed channel symbol rate of 1200 symbol/sec, the information rate ranges from 2400 bps using 4FSK up to 3600 bps using 8PSK for SNR ranges from 11dB up to 26dB.

  19. Hybrid superconducting neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Merlo, V.; Lucci, M.; Ottaviani, I. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); Salvato, M.; Cirillo, M. [Dipartimento di Fisica, Università Tor Vergata, Via della Ricerca Scientifica, I-00133 Roma (Italy); CNR SPIN Salerno, Università di Salerno, Via Giovanni Paolo II, n.132, 84084 Fisciano (Italy); Scherillo, A. [Science and Technology Facility Council, ISIS Facility Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Celentano, G. [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Pietropaolo, A., E-mail: antonino.pietropaolo@enea.it [ENEA Frascati Research Centre, Via. E. Fermi 45, 00044 Frascati (Italy); Mediterranean Institute of Fundamental Physics, Via Appia Nuova 31, 00040 Marino, Roma (Italy)

    2015-03-16

    A neutron detection concept is presented that is based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies on the nuclear reaction, {sup 10}B + n → α + {sup 7}Li, with α and Li ions generating a hot spot on the current-biased Nb strip which in turn induces a superconducting-normal state transition. The latter is recognized as a voltage signal which is the evidence of the incident neutron. The above described detection principle has been experimentally assessed and verified by irradiating the samples with a pulsed neutron beam at the ISIS spallation neutron source (UK). It is found that the boron coated superconducting strips, kept at a temperature T = 8 K and current-biased below the critical current I{sub c}, are driven into the normal state upon thermal neutron irradiation. As a result of the transition, voltage pulses in excess of 40 mV are measured while the bias current can be properly modulated to bring the strip back to the superconducting state, thus resetting the detector. Measurements on the counting rate of the device are presented and the basic physical features of the detector are discussed.

  20. MUON DETECTORS: DT

    CERN Multimedia

    M. Dallavalle.

    The DT system is ready for the LHC start up. The status of detector hardware, control and safety, of the software for calibration and monitoring and of people has been reviewed at several meetings, starting with the CMS Action Matrix Review and with the Muon Barrel Workshop (October 5 to 7). The disconnected HV channels are at a level of about 0.1%. The loss in detector acceptance because of failures in the Read-Out and Trigger electronics is about 0.5%. The electronics failure rate has been lower this year: next year will tell us whether the rate has stabilised and hopefully will confirm that the number of spares is adequate for ten years operation. Although the detector safety control is very accurate and robust, incidents have happened. In particular the DT system suffered from a significant water leak, originated in the top part of YE+1, that generated HV trips in eighteen chambers going transversely down from the top sector in YB+2 to the bottom sector in YB-2. All chambers recovered and all t...

  1. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2011-01-01

    During data-taking in 2010 the RPC system behaviour was very satisfactory for both the detector and trigger performances. Most of the data analyses are now completed and many results and plots have been approved in order to be published in the muon detector paper. A very detailed analysis of the detector efficiency has been performed using 60 million muon events taken with the dedicated RPC monitor stream. The results have shown that the 96.3% of the system was working properly with an average efficiency of 95.4% at 9.35 kV in the Barrel region and 94.9% at 9.55 kV in the Endcap. Cluster size goes from 1.6 to 2.2 showing a clear and well-known correlation with the strip pitch. Average noise in the Barrel is less than 0.4 Hz/cm2 and about 98% of full system has averaged noise less then 1 Hz/cm2. A linear dependence of the noise versus the luminosity has been preliminary observed and is now under study. Detailed chamber efficiency maps have shown a few percent of chambers with a non-uniform efficiency distribu...

  2. UA1 prototype detector

    CERN Multimedia

    1980-01-01

    Prototype of UA1 central detector inside a plexi tube. The UA1 central detector was crucial to understanding the complex topology of proton-antiproton events. It played a most important role in identifying a handful of Ws and Zs among billions of collisions. The detector was a 6-chamber cylindrical assembly 5.8 m long and 2.3 m in diameter, the largest imaging drift chamber of its day. It recorded the tracks of charged particles curving in a 0.7 Tesla magnetic field, measuring their momentum, the sign of their electric charge and their rate of energy loss (dE/dx). Atoms in the argon-ethane gas mixture filling the chambers were ionised by the passage of charged particles. The electrons which were released drifted along an electric field shaped by field wires and were collected on sense wires. The geometrical arrangement of the 17000 field wires and 6125 sense wires allowed a spectacular 3-D interactive display of reconstructed physics events to be produced.

  3. The STAR PXL detector

    Science.gov (United States)

    Contin, G.

    2016-12-01

    The PiXeL detector (PXL) of the STAR experiment at RHIC is the first application of the state-of-the-art thin Monolithic Active Pixel Sensors (MAPS) technology in a collider environment. Designed to extend the STAR measurement capabilities in the heavy flavor domain, it took data in Au+Au collisions, p+p and p+Au collisions at 0√sNN=20 GeV at RHIC, during the period 2014-2016. The PXL detector is based on 50 μm-thin MAPS sensors with a pitch of 20.7 μm. Each sensor includes an array of nearly 1 million pixels, read out in rolling shutter mode in 185.6 μs. The 170 mW/cm2 power dissipation allows for air cooling and contributes to reduce the global material budget to 0.4% radiation length on the innermost layer. Experience and lessons learned from construction and operations will be presented in this paper. Detector performance and results from 2014 Au+Au data analysis, demonstrating the STAR capabilities of charm reconstruction, will be shown.

  4. MUON DETECTORS: RPC

    CERN Multimedia

    P. Paolucci

    2011-01-01

    RPC detector calibration, HV scan Thanks to the high LHC luminosity and to the corresponding high number of muons created in the first part of the 2011 the RPC community had, for the first time, the possibility to calibrate every single detector element (roll).The RPC steering committee provided the guidelines for both data-taking and data analysis and a dedicated task force worked from March to April on this specific issue. The main goal of the RPC calibration was to study the detector efficiency as a function of high-voltage working points, fit the obtained “plateau curve” with a sigmoid function and determine the “best” high-voltage working point of every single roll. On 18th and 19th March, we had eight runs at different voltages. On 27th March, the full analysis was completed, showing that 60% of the rolls had already a very good fit with an average efficiency greater than 93% in the plateau region. To improve the fit we decided to take three more runs (15th April...

  5. Commissioning the SNO+ detector

    Science.gov (United States)

    Descamps, Freija; SNO+ Collaboration

    2016-09-01

    The SNO+ experiment is the successor to the Sudbury Neutrino Observatory (SNO), in which SNO's heavy water is replaced by approximately 780T of liquid scintillator (LAB). The combination of the 2km underground location, the use of ultra-clean materials and the high light-yield of the liquid scintillator means that a low background level and a low energy threshold can be achieved. This creates a new multipurpose neutrino detector with the potential to address a diverse set of physics goals, including the detection of reactor, solar, geo- and supernova neutrinos. A main physics goal of SNO+ is the search for neutrinoless double beta decay. By loading the liquid scintillator with 0.5% of natural Tellurium, resulting in about 1300kg of 130Te (isotopic abundance is slightly over 34%), a competitive sensitivity to the effective neutrino mass can be reached. This talk will present the status of the SNO+ detector, specifically the results and status of the detector commissioning with water.

  6. The STAR Vertex Position Detector

    CERN Document Server

    Llope, W J; Nussbaum, T; Hoffmann, G W; Asselta, K; Brandenburg, J D; Butterworth, J; Camarda, T; Christie, W; Crawford, H J; Dong, X; Engelage, J; Eppley, G; Geurts, F; Hammond, J; Judd, E; McDonald, D L; Perkins, C; Ruan, L; Scheblein, J; Schambach, J J; Soja, R; Xin, K; Yang, C

    2014-01-01

    The 2x3 channel pseudo Vertex Position Detector (pVPD) in the STAR experiment at RHIC has been upgraded to a 2x19 channel detector in the same acceptance, called the Vertex Position Detector (VPD). This detector is fully integrated into the STAR trigger system and provides the primary input to the minimum-bias trigger in Au+Au collisions. The information from the detector is used both in the STAR Level-0 trigger and offline to measure the location of the primary collision vertex along the beam pipe and the event "start time" needed by other fast-timing detectors in STAR. The offline timing resolution of single detector channels in full-energy Au+Au collisions is ~100 ps, resulting in a start time resolution of a few tens of picoseconds and a resolution on the primary vertex location of ~1 cm.

  7. The Thermodynamic Characterization of ZrCo–H, HfCo−H, HfNi−H and Zr{sub 1–x}HfxNi(Co) Alloy–H Systems

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, Ted B., E-mail: ted.flanagan@uvm.edu; Noh, Hak; Luo, Suifang

    2016-08-25

    ZrCo and HfCo intermetallic compounds have the same cubic (CsCl-type) structure and their ternary (Zr{sub 1−x}Hf{sub x})Co alloys are also cubic. ZrNi and HfNi intermetallic compounds have the orthorhombic structure (CrB-type) and the ternary (Zr{sub 1−x}Hf{sub x})Ni alloys also have this structure. Thermodynamic data for hydride formation and decomposition in ZrCo, HfCo and HfNi intermetallic compounds have been determined from reaction calorimetry and from pressure-composition isotherms. Thermodynamic data have been determined for the three ternary alloys: (Zr{sub 0.75}Hf{sub 0.25})Co, (Zr{sub 0.50}Hf{sub 0.50})Co, and (Zr{sub 0.25}Hf{sub 0.75})Co and the four ternary alloys: (Zr{sub 0.875}Hf{sub 0.125})Ni, (Zr{sub 0.75}Hf{sub 0.25})Ni, (Zr{sub 0.50}Hf{sub 0.50})Ni, and (Zr{sub 0.25}Hf{sub 0.75})Ni. This offers the opportunity to learn how the thermodynamic properties of the ternary alloy-H systems change with the stoichiometry of alloys with the same structure. - Highlights: • Calorimetric enthalpies determined for H absorption by ZrCo, HfCo, HfNi are determined. • Ternary alloys, e.g., Zr{sub 1−x}Hf{sub x}Ni, prepared and characterized by x-ray diffraction. • Isotherms for the ternary alloys give thermodynamic parameters for H solution.

  8. Single layer of Ge quantum dots in HfO2 for floating gate memory capacitors.

    Science.gov (United States)

    Lepadatu, A M; Palade, C; Slav, A; Maraloiu, A V; Lazanu, S; Stoica, T; Logofatu, C; Teodorescu, V S; Ciurea, M L

    2017-04-28

    High performance trilayer memory capacitors with a floating gate of a single layer of Ge quantum dots (QDs) in HfO2 were fabricated using magnetron sputtering followed by rapid thermal annealing (RTA). The layer sequence of the capacitors is gate HfO 2/floating gate of single layer of Ge QDs in HfO 2/tunnel HfO 2/p-Si wafers. Both Ge and HfO2 are nanostructured by RTA at moderate temperatures of 600-700 °C. By nanostructuring at 600 °C, the formation of a single layer of well separated Ge QDs with diameters of 2-3 nm at a density of 4-5 × 10(15) m(-2) is achieved in the floating gate (intermediate layer). The Ge QDs inside the intermediate layer are arranged in a single layer and are separated from each other by HfO2 nanocrystals (NCs) about 8 nm in diameter with a tetragonal/orthorhombic structure. The Ge QDs in the single layer are located at the crossing of the HfO2 NCs boundaries. In the intermediate layer, besides Ge QDs, a part of the Ge atoms is segregated by RTA at the HfO2 NCs boundaries, while another part of the Ge atoms is present inside the HfO2 lattice stabilizing the tetragonal/orthorhombic structure. The fabricated capacitors show a memory window of 3.8 ± 0.5 V and a capacitance-time characteristic with 14% capacitance decay in the first 3000-4000 s followed by a very slow capacitance decrease extrapolated to 50% after 10 years. This high performance is mainly due to the floating gate of a single layer of well separated Ge QDs in HfO2, distanced from the Si substrate by the tunnel oxide layer with a precise thickness.

  9. Garnet effect on Nd-Hf isotope decoupling: Evidence from the Jinfosi batholith, Northern Tibetan Plateau

    Science.gov (United States)

    Huang, Hui; Niu, Yaoling; Mo, Xuanxue

    2017-03-01

    The initial Nd and Hf isotope ratios of a 420 Ma post-collisional dioritic-granitic batholith from the Northern Tibetan plateau define a negative trend above and orthogonal to the ԐHf(t)-ԐNd(t) terrestrial array. This uncommon trend offers an insight into the origin of the puzzling Nd-Hf isotope decoupling in the crustal rocks. On this trend, samples depleted in heavy rare earth elements (HREEs, i.e., [Dy/Yb]N ≫ 1) deviate most from the terrestrial array whereas samples with flat HREEs (i.e., [Dy/Yb]N ≥ 1) deviate less or plot within the terrestrial array, pointing to the controlling effect of garnet in the magma source. Ancient garnet-bearing residues after melt extraction will have elevated Lu/Hf ratios and can evolve with time to produce high ԐHf(t) at a low ԐNd(t) value. Mixing of melts derived from such source lithologies (high Lu/Hf) with melts possessing a within-terrestrial array Nd-Hf isotopic composition (low Lu/Hf) best explains the observed trend orthogonal to the terrestrial array. The samples from the Jinfosi batholith with the most decoupled Nd-Hf isotope compositions require a larger degree (> 40%) and ancient (i.e., ≥ 1.8 Gyr) previous melt extraction from their source. It follows that the ancient melts with depleted HREEs complementary to those garnet-bearing residues should have low ԐHf values and plot below the terrestrial array, which is indeed shown by some Archean/Paleoproterozic TTGs.

  10. Hardness and Second Phase Percentage of Ni-Ti-Hf Compounds After Heat Treatment at 700C

    Science.gov (United States)

    Stanford, Malcolm K.

    2017-01-01

    The Vickers hardness and second phase precipitation of three ternary intermetallic Ni-Ti-Hf compounds containing either 1, 3 or 5 at.% Hf were compared to 60-Nitinol (55 at.% Ni - 45 at.% Ti). Heat treatment either at 700 C or with a subsequent aging step, hardened the 3 and 5 at.% Hf-containing ternaries to approximately 620 HV (56 HRC). Heat treatment increased the hardness of the 1 at.% Hf compound by more than 25 percent. Average hardness of the 3 and 5 at.% Hf ternaries, though higher than that of the binary Ni-Ti or the Ni-Ti-Hf compound containing 1 at.% Hf, appeared to be fairly insensitive to the different heat treatments. There was a drastic reduction of fatigue-enhancing second phase precipitates for the 5 at.% Hf ternaries compared to the other compounds. These results should guide materials selection for development of aerospace componentry.

  11. Mixing and melt sources in the Miocene Aztec Wash pluton (Nevada, USA) as revealed by zircon Hf and O and whole rock Sr, Nd, and Hf isotopes

    Science.gov (United States)

    Ryan, M.; Miller, J. S.; Miller, C. F.; Bromley, S.; Davies, G. R.; Schmitt, A. K.

    2011-12-01

    The 15.6 Ma Aztec Wash Pluton (AWP) is one of several Miocene intrusions located within the northern Colorado River extensional corridor. Extensive E-W tilting of fault blocks has exposed the pluton from the roof to 5 km structural depth. Earlier field and petrologic studies subdivided the AWP into two distinct zones: (1) a Granite Zone (GZ) comprised of relatively homogeneous granite with subtle differences in textures and mineralogy; (2) a Heterogeneous Zone (HZ), which interfingers the GZ, contains evidence for mafic and felsic magma input with a wide compositional range (42-78 wt% SiO2), and abundant field evidence for hybridization. Previous whole rock geochemistry and zircon trace element analyses indicated that compositional variation was produced by multi-component mixing between mafic and felsic melts within the HZ. New whole rock Sr, Nd, and Hf isotope data from the HZ show that all rocks (including high-silica granites) formed by mixing Precambrian crust and enriched mantle, with mixtures having a large mantle fraction (≥50%). New Hf (n=189) and O (n=241) isotope analyses of zircon from samples in the HZ confirm these melt sources and provide a broader perspective on hybridization processes within the AWP. Zircon grains from all samples show heterogeneous Hf and O isotopic compositions (-5 to -18 ɛHf; 4.5-7.5% δ18O), but despite the clear signature of Precambrian crust in the whole rock data, obvious Precambrian zircons (or cores) were mostly absent; only one zircon was clearly Precambrian (ɛHf = -25). Resolvable intragrain variability is relatively limited (including the Precambrian grain, which is unzoned). Zircons from hand samples and from compositional groups also show heterogeneous ɛHf and δ18O values, although the spreads are more restricted than in the whole data set (6-10 ɛHf in granites, 5-7 ɛHf in intermediate "hybrids", 5-6 ɛHf in gabbro/diorite sheets). Oxygen isotope values for the zircons also show intra-handsample heterogeneity

  12. Computational-Experimental Processing of Boride/Carbide Composites by Reactive Infusion of Hf Alloy Melts into B4C

    Science.gov (United States)

    2015-09-16

    elements from the Hf family (i.e., Hf, Ti and Zr ) into a capillary to understand the effects of surface tension and viscosity during processing of melts...project primarily investigated computationally the infusion of liquid elements from the Hf family (i.e., Hf, Ti and Zr ) into a capillary to understand the... effects of surface tension and viscosity during processing of melts with a packed bed of B4C to form boride-carbide precipitates. Although the

  13. Structure, optical properties and thermal stability of HfErO films deposited by simultaneous RF and VHF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H.Y. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Nanjing University of Posts and Telecommunications, School of Tongda, Nanjing (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); He, H.J.; Zhang, Z.; Jin, C.G.; Yang, Y.; Wang, Y.Y.; Ye, C. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Zhuge, L.J. [Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Soochow University, Analysis and Testing Center, Suzhou (China); Wu, X.M. [Soochow University, College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China); Soochow University, Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province and Key Lab of Modern Optical Technologies of Education Ministry of China, Suzhou (China); Chinese Academy of Sciences, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Shanghai (China)

    2015-01-23

    HfErO films are deposited on Si substrates by simultaneous radio frequency (RF) and very high frequency (VHF) magnetron sputtering technique. The content of the doped ingredient of Er and the body composition of HfO{sub x} are, respectively, controlled through the VHF and RF powers. Low content of Er doping in the HfErO films can be achieved, because the VHF source of 27.12 MHz has higher ion energy and lower ion flux than the RF source resulting in low sputtering rate in the magnetron sputtering system. The structure, optical properties and thermal stability of the HfErO films are investigated in this work. Results show that the doped content of Er is independently controlled by the VHF power. The oxygen vacancies are created by the Er incorporation. The hafnium in the HfErO films forms mixed valence of Hf{sup 2+} and Hf{sup 4+}. The HfErO films are composed with the structures of HfO{sub 2}, HfO and ErO{sub x}, which can be optimized through the VHF power. At high VHF power, the Hf-Er-O bonds are formed, which demonstrates that the Er atoms are doped into the lattice of HfO{sub 2} in the HfErO films. The HfErO films have bad thermal stability as the crystallization temperature decreases from 900 to 800 C. After thermal annealing, cubic phase of HfO{sub 2} are stabilized, which is ascribed to the oxygen vacancies creation by the Er incorporation. The optical properties such as the refractive index and the optical band gap of the HfErO films are optimized by the VHF power. (orig.)

  14. Trimming the threshold dispersion below 10 e-rms in a large area readout IC working in a single photon counting mode

    Science.gov (United States)

    Kmon, P.; Maj, P.; Gryboś, P.; Szczygieł, R.

    2016-01-01

    We present a new method of an in-pixel threshold dispersion correction implemented in a prototype readout integrated circuit (IC) operating in a single photon counting mode. The new threshold correction method was implemented in a readout IC of area 9.6× 14.9 mm2 containing 23552 square pixels with the pitch of 75 μm designed and fabricated in CMOS 130 nm technology. Each pixel of the IC consists of a charge sensitive amplifier, a shaper, two discriminators, two 14-bit counters and a low-area trim DACs for threshold correction. The user can either control the range of the trim DAC globally for all the pixels in the integrated circuit or modify the trim DACs characteristics locally in each pixel independently. Using a simulation tool based on the Monte-Carlo methods, we estimated how much we could improve the offset trimming by increasing the number of bits in the trim DACs or implementing additional bits in a pixel to modify the characteristics of the trim DACs. The measurements of our IC prototype show that it is possible to reduce the effective threshold dispersion in large-area single-photon counting chips below 10 electrons rms.

  15. A model for the energy-dependent time-lag and rms of the heartbeat oscillations in GRS 1915+105

    CERN Document Server

    Mir, Mubashir Hamid; Pahari, Mayukh; Iqbal, Naseer; Ahmad, Naveel

    2016-01-01

    Energy dependent phase lags reveal crucial information about the causal relation between various spectral components and about the nature of the accretion geometry around the compact objects. The time-lag and the fractional root mean square (rms) spectra of GRS 1915+105 in its heartbeat oscillation class/$\\rho$ state show peculiar behaviour at the fundamental and harmonic frequencies where the lags at the fundamental show a turn around at $\\sim$ 10 keV while the lags at the harmonic do not show any turn around at least till $\\sim$ 20 keV. The magnitude of lags are of the order of few seconds and hence cannot be attributed to the light travel time effects or Comptonization delays. The continuum X-ray spectra can roughly be described by a disk blackbody and a hard X-ray power-law component and from phase resolved spectroscopy it has been shown that the inner disk radius varies during the oscillation. Here, we propose that there is a delayed response of the inner disk radius (DROID) to the accretion rate such th...

  16. The DELPHI Detector (DEtector with Lepton Photon and Hadron Identification)

    CERN Multimedia

    Crawley, B; Munich, K; Mckay, R; Matorras, F; Joram, C; Malychev, V; Behrmann, A; Van dam, P; Drees, J K; Stocchi, A; Adam, W; Booth, P; Bilenki, M; Rosenberg, E I; Morton, G; Rames, J; Hahn, S; Cosme, G; Ventura, L; Marco, J; Tortosa martinez, P; Monge silvestri, R; Moreno, S; Phillips, H; Alekseev, G; Boudinov, E; Martinez rivero, C; Gitarskiy, L; Davenport, M; De clercq, C; Firestone, A; Myagkov, A; Belous, K; Haider, S; Hamilton, K M; Lamsa, J; Rahmani, M H; Malek, A; Hughes, G J; Peralta, L; Carroll, L; Fuster verdu, J A; Cossutti, F; Gorn, L; Yi, J I; Bertrand, D; Myatt, G; Richard, F; Shapkin, M; Hahn, F; Ferrer soria, A; Reinhardt, R; Renton, P; Sekulin, R; Timmermans, J; Baillon, P

    2002-01-01

    % DELPHI The DELPHI Detector (Detector with Lepton Photon and Hadron Identification) \\\\ \\\\DELPHI is a general purpose detector for physics at LEP on and above the Z$^0$, offering three-dimensional information on curvature and energy deposition with fine spatial granularity as well as identification of leptons and hadrons over most of the solid angle. A superconducting coil provides a 1.2~T solenoidal field of high uniformity. Tracking relies on the silicon vertex detector, the inner detector, the Time Projection Chamber (TPC), the outer detector and forward drift chambers. Electromagnetic showers are measured in the barrel with high granularity by the High Density Projection Chamber (HPC) and in the endcaps by $ 1 ^0 $~x~$ 1 ^0 $ projective towers composed of lead glass as active material and phototriode read-out. Hadron identification is provided mainly by liquid and gas Ring Imaging Counters (RICH). The instrumented magnet yoke serves for hadron calorimetry and as filter for muons, which are identified in t...

  17. The TDCpix readout ASIC: A 75ps resolution timing front-end for the NA62 Gigatracker hybrid pixel detector

    CERN Document Server

    Kluge, A; Bonacini, S; Jarron, P; Kaplon, J; Morel, M; Noy, M; Perktold, L; Poltorak, K

    2013-01-01

    The TDCpix is a novel pixel readout ASIC for the NA62 Gigatracker detector. NA62 is a new experiment being installed at the CERN Super Proton Synchrotron. Its Gigatracker detector shall provide on-beam tracking and time stamping of individual particles with a time resolution of 150 ps rms. It will consist of three tracking stations, each with one hybrid pixel sensor. The peak fl ow of particles crossing the detector modules reaches 1.27 MHz/mm 2 for a total rate of about 0.75 GHz. Ten TDCpix chips will be bump-bonded to every silicon pixel sensor. Each chip shall perform time stamping of 100 M particle hits per second with a detection ef fi ciency above 99% and a timing accuracy better than 200 ps rms for an overall three-station-setup time resolution of better than 150 ps. The TDCpix chip has been designed in a 130 nm CMOS technology. It will feature 45 40 square pixels of 300 300 μ m 2 and a complex End of Column peripheral region including an array of TDCs based on DLLs, four high speed serializers, a low...

  18. A low-power CMOS ASIC for X-ray Silicon Drift Detectors low-noise pulse processing

    Science.gov (United States)

    Ahangarianabhari, M.; Bertuccio, G.; Macera, D.; Malcovati, P.; Grassi, M.; Rashevsky, A.; Rashevskaya, I.; Vacchi, A.; Zampa, G.; Zampa, N.; Fuschino, F.; Evangelista, Y.; Campana, R.; Labanti, C.; Feroci, M.

    2014-03-01

    We present an Application Specific Integrated Circuit (ASIC), named VEGA-1, designed and manufactured for low-power analog pulse processing of signals from Silicon Drift Detectors (SDDs). The VEGA-1 ASIC consists of an analog and a digital/mixed-signal section to achieve all the functionalities and specifications required for high-resolution X-ray spectroscopy in the energy range from 500 eV to 60 keV with low power consumption. The VEGA-1 ASIC has been designed and manufactured in 0.35-μm CMOS mixed-signal technology in single and 32-channel version with dimensions of 200 μm × 500 μm per channel. A minimum intrinsic ENC of 12 electrons r.m.s. at 3.6 μs shaping time and room temperature is measured for the ASIC without detector. The VEGA-1 has been tested with Q10-SDD designed in Trieste and fabricated at FBK, with an active area of 10 mm2 and a thickness of 450 μm. The aforementioned detector has an anode current of about 180 pA at +22°C. A minimum Equivalent Noise Charge (ENC) of 16 electrons r.m.s. at 3.0 μs shaping time and -30°C has been demonstrated with a total measured power consumption of 482 μW.

  19. Archean Lithosphere Beneath Arctic Canada: Lu-Hf Isotope Systematics for Kimberlite-Hosted Garnet-Peridotites From Somerset Island

    Science.gov (United States)

    Schmidberger, S. S.; Simonetti, A.; Francis, D.; Gariepy, C.

    2001-05-01

    Knowledge of the age of lithospheric mantle underlying the continents provides valuable constraints for the timing of formation and stabilization of Archean cratons. This study reports Lu-Hf isotopic data for garnet-peridotites, and their constituent garnets, from the Nikos kimberlite (100 Ma) on Somerset Island in the Canadian Arctic obtained using a Micromass IsoProbe multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS) at GEOTOP-UQAM. The low temperature peridotites (1100 C; 160-190 km) and their 176Hf/177Hf(0.1Ga) isotopic compositions (0.28265-0.28333; \\epsilonHf(0.1Ga)=-2 to +22) are less radiogenic than those of the shallow xenoliths. A Lu-Hf isochron for six peridotites yields a mid Archean age of 3.4\\pm0.3 Ga and an initial 176Hf/177Hf ratio of 0.28101\\pm24. The remaining peridotites (n=9), in contrast, are characterized by extremely high (+35) initial \\epsilonHf(3.4Ga) values, which correlate negatively with their 176Lu/177Hf ratios, suggesting addition of Hf as a result of metasomatic interaction with the host kimberlite. The garnets from the low temperature (3.4 Ga old) peridotites are characterized by high 176Lu/177Hf ratios and define an errorchron age of 1.4\\pm0.2 Ga, which may reflect re-equilibration of Hf during kimberlite magmatism.

  20. Design for human factors (DfHF): a grounded theory for integrating human factors into production design processes.

    Science.gov (United States)

    Village, Judy; Searcy, Cory; Salustri, Filipo; Patrick Neumann, W

    2015-01-01

    The 'design for human factors' grounded theory explains 'how' human factors (HF) went from a reactive, after-injury programme in safety, to being proactively integrated into each step of the production design process. In this longitudinal case study collaboration with engineers and HF Specialists in a large electronics manufacturer, qualitative data (e.g. meetings, interviews, observations and reflections) were analysed using a grounded theory methodology. The central tenet in the theory is that when HF Specialists acclimated to the engineering process, language and tools, and strategically aligned HF to the design and business goals of the organisation, HF became a means to improve business performance. This led to engineers 'pulling' HF Specialists onto their team. HF targets were adopted into engineering tools to communicate HF concerns quantitatively, drive continuous improvement, visibly demonstrate change and lead to benchmarking. Senior management held engineers accountable for HF as a key performance indicator, thus integrating HF into the production design process. Practitioner Summary: Research and practice lack explanations about how HF can be integrated early in design of production systems. This three-year case study and the theory derived demonstrate how ergonomists changed their focus to align with design and business goals to integrate HF into the design process.