Review of high bandwidth fiber optics radiation sensors

International Nuclear Information System (INIS)

Lyons, P.B.

1985-01-01

This paper summarizes the use of fiber optics or guided optical systems for radiation sensors. It is limited a passive systems wherein electrical is not required at the sensor location. However, electrically powered light sources, receivers and/or recorders may still be required for detection and data storage in sensor system operation. This paper emphasizes sensor technologies that permit high bandwidth measurements of transient radiation levels, and will also discuss several low bandwidth applications. 60 refs

Development of a readout technique for the high data rate BTeV pixel detector at Fermilab

International Nuclear Information System (INIS)

Hall, Bradley K.

2001-01-01

The pixel detector for the BTeV experiment at Fermilab provides digitized data from approximately 22 million silicon pixel channels. Portions of the detector are six millimeters from the beam providing a substantial hit rate and high radiation dose. The pixel detector data will be employed by the lowest level trigger system for track reconstruction every beam crossing. These requirements impose a considerable constraint on the readout scheme. This paper presents a readout technique that provides the bandwidth that is adequate for high hit rates, minimizes the number of radiation hard components, and satisfies all other design constraints

Ultra-high bandwidth quantum secured data transmission

Science.gov (United States)

Dynes, James F.; Tam, Winci W.-S.; Plews, Alan; Fröhlich, Bernd; Sharpe, Andrew W.; Lucamarini, Marco; Yuan, Zhiliang; Radig, Christian; Straw, Andrew; Edwards, Tim; Shields, Andrew J.

2016-10-01

Quantum key distribution (QKD) provides an attractive means for securing communications in optical fibre networks. However, deployment of the technology has been hampered by the frequent need for dedicated dark fibres to segregate the very weak quantum signals from conventional traffic. Up until now the coexistence of QKD with data has been limited to bandwidths that are orders of magnitude below those commonly employed in fibre optic communication networks. Using an optimised wavelength divisional multiplexing scheme, we transport QKD and the prevalent 100 Gb/s data format in the forward direction over the same fibre for the first time. We show a full quantum encryption system operating with a bandwidth of 200 Gb/s over a 100 km fibre. Exploring the ultimate limits of the technology by experimental measurements of the Raman noise, we demonstrate it is feasible to combine QKD with 10 Tb/s of data over a 50 km link. These results suggest it will be possible to integrate QKD and other quantum photonic technologies into high bandwidth data communication infrastructures, thereby allowing their widespread deployment.

THz Tube Waveguides With Low Loss, Low Dispersion, and High Bandwidth

DEFF Research Database (Denmark)

Bao, Hualong; Nielsen, Kristian; Bang, Ole

2014-01-01

We propose, model and experimentally characterize a novel class of terahertz hollow-core tube waveguides with high-loss cladding material, resulting in propagation with low loss, low dispersion, and high useful bandwidth.......We propose, model and experimentally characterize a novel class of terahertz hollow-core tube waveguides with high-loss cladding material, resulting in propagation with low loss, low dispersion, and high useful bandwidth....

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.

Managing high-bandwidth real-time data storage

Energy Technology Data Exchange (ETDEWEB)

Bigelow, David D. [Los Alamos National Laboratory; Brandt, Scott A [Los Alamos National Laboratory; Bent, John M [Los Alamos National Laboratory; Chen, Hsing-Bung [Los Alamos National Laboratory

2009-09-23

There exist certain systems which generate real-time data at high bandwidth, but do not necessarily require the long-term retention of that data in normal conditions. In some cases, the data may not actually be useful, and in others, there may be too much data to permanently retain in long-term storage whether it is useful or not. However, certain portions of the data may be identified as being vitally important from time to time, and must therefore be retained for further analysis or permanent storage without interrupting the ongoing collection of new data. We have developed a system, Mahanaxar, intended to address this problem. It provides quality of service guarantees for incoming real-time data streams and simultaneous access to already-recorded data on a best-effort basis utilizing any spare bandwidth. It has built in mechanisms for reliability and indexing, can scale upwards to meet increasing bandwidth requirements, and handles both small and large data elements equally well. We will show that a prototype version of this system provides better performance than a flat file (traditional filesystem) based version, particularly with regard to quality of service guarantees and hard real-time requirements.

Reconstitution of Low Bandwidth Reaction History

International Nuclear Information System (INIS)

May, M.; Clancy, T.; Fittinghoff, D.; Gennaro, P.; Hagans, K.; Halvorson, G.; Lowry, M.; Perry, T.; Roberson, P.; Smith, D.; Teruya, A.; Blair, J.; Davis, B.; Hunt, E.; Emkeit, B.; Galbraith, J.; Kelly, B.; Montoya, R.; Nickel, G.; Ogle, J.; Wilson, K.; Wood, M.

2004-01-01

reaction history. The first step in the reconstitution of reaction history was thus naturally the reconstitution of the loW--bandwidth capability in FY04. This will be followed in FY06 by the reconstitution of the high bandwidth capability. The reconstitution of the loW--bandwidth reaction history measurement was done in several phases. First the status of legacy equipment has been ascertained. Existing detectors, cables, and recording systems have been inventoried, characterized and, for the most part, satisfied the specifications of the test program and are still useable. The ability to obtain replacement equipment is now available. Modern loW--bandwidth fiber optic recording equipment which was similar to systems used on the old tests, has been evaluated. The ability to characterize and calibrate detectors and other components has been reestablished. New scientists and engineers have been working with designated mentors. These mentors participated on numerous shots during the old test program. Finally as a proof test, two hypothetical test scenarios were proposed: one each from LLNL and LANL. The LANL event was called ALPHA and the LLNL event was called POPOUT. The reaction history diagnostics for these two hypothetical underground tests were completely laid out and analyzed to make sure that the diagnostic could be successfully fielded within a 24 month time frame. In addition as part of a training exercise a reaction history trailer was reconstituted. This system was configured using a combination of new and experienced technical personnel and data analysts in collaboration with LLNL and LANL event physicists

LEVEL-1 DATA DRIVER CARD - A high bandwidth radiation tolerant aggregator board for detectors

CERN Document Server

Gkountoumis, Panagiotis; The ATLAS collaboration

2018-01-01

The Level-1 Data Driver Card (L1DDC) was designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The detectors located at the muon Small Wheels will be replaced by a set of precision tracking and trigger detectors, the resistive Micromegas (MM) and the small-strip Thin Gap Chambers (sTGC). After the upgrade, the number of interactions per bunch-crossing will be increased up to 140, resulting in a dramatically large amount of produced data. The high number of electronic channels (about two million for the MM and about 300k for the sTGC) along with a harsh environment (radiation dose up to 1700Gy (inner radius) and a magnetic field up to 0:4T in the end cap region) led to the development of new radiation tolerant electronics and a scalable readout scheme able to handle the new data rates. In addition, correction mechanisms for Single Event Upsets (SEU) and communication errors must be implemented to assure the integrity of the transmitted data. The L1DDC i...

Optical interconnect technologies for high-bandwidth ICT systems

Science.gov (United States)

Chujo, Norio; Takai, Toshiaki; Mizushima, Akiko; Arimoto, Hideo; Matsuoka, Yasunobu; Yamashita, Hiroki; Matsushima, Naoki

2016-03-01

The bandwidth of information and communication technology (ICT) systems is increasing and is predicted to reach more than 10 Tb/s. However, an electrical interconnect cannot achieve such bandwidth because of its density limits. To solve this problem, we propose two types of high-density optical fiber wiring for backplanes and circuit boards such as interface boards and switch boards. One type uses routed ribbon fiber in a circuit board because it has the ability to be formed into complex shapes to avoid interfering with the LSI and electrical components on the board. The backplane is required to exhibit high density and flexibility, so the second type uses loose fiber. We developed a 9.6-Tb/s optical interconnect demonstration system using embedded optical modules, optical backplane, and optical connector in a network apparatus chassis. We achieved 25-Gb/s transmission between FPGAs via the optical backplane.

Research of high speed data readout and pre-processing system based on xTCA for silicon pixel detector

International Nuclear Information System (INIS)

Zhao Jingzhou; Lin Haichuan; Guo Fang; Liu Zhen'an; Xu Hao; Gong Wenxuan; Liu Zhao

2012-01-01

As the development of the detector, Silicon pixel detectors have been widely used in high energy physics experiments. It needs data processing system with high speed, high bandwidth and high availability to read data from silicon pixel detectors which generate more large data. The same question occurs on Belle II Pixel Detector which is a new style silicon pixel detector used in SuperKEKB accelerator with high luminance. The paper describes the research of High speed data readout and pre-processing system based on xTCA for silicon pixel detector. The system consists of High Performance Computer Node (HPCN) based on xTCA and ATCA frame. The HPCN consists of 4XFPs based on AMC, 1 AMC Carrier ATCA Board (ACAB) and 1 Rear Transmission Module. It characterized by 5 high performance FPGAs, 16 fiber links based on RocketIO, 5 Gbit Ethernet ports and DDR2 with capacity up to 18GB. In a ATCA frame, 14 HPCNs make up a system using the high speed backplane to achieve the function of data pre-processing and trigger. This system will be used on the trigger and data acquisition system of Belle II Pixel detector. (authors)

A high control bandwidth design method for aalborg inverter under weak grid condition

DEFF Research Database (Denmark)

Wu, Weimin; Zhou, Cong; Wang, Houqin

2017-01-01

Aalborg Inverter is a kind of high efficient Buck-Boost inverter. Since it may work in “Buck-Boost” mode, the control bandwidth should be high enough to ensure a good performance under any grid condition. However, during the “Boost” operation, the control bandwidth depends much on the grid...

THE IMPROVEMENT OF COMPUTER NETWORK PERFORMANCE WITH BANDWIDTH MANAGEMENT IN KEMURNIAN II SENIOR HIGH SCHOOL

Directory of Open Access Journals (Sweden)

Bayu Kanigoro

2012-05-01

Full Text Available This research describes the improvement of computer network performance with bandwidth management in Kemurnian II Senior High School. The main issue of this research is the absence of bandwidth division on computer, which makes user who is downloading data, the provided bandwidth will be absorbed by the user. It leads other users do not get the bandwidth. Besides that, it has been done IP address division on each room, such as computer, teacher and administration room for supporting learning process in Kemurnian II Senior High School, so wireless network is needed. The method is location observation and interview with related parties in Kemurnian II Senior High School, the network analysis has run and designed a new topology network including the wireless network along with its configuration and separation bandwidth on microtic router and its limitation. The result is network traffic on Kemurnian II Senior High School can be shared evenly to each user; IX and IIX traffic are separated, which improve the speed on network access at school and the implementation of wireless network.Keywords: Bandwidth Management; Wireless Network

High-fidelity polarization storage in a gigahertz bandwidth quantum memory

International Nuclear Information System (INIS)

England, D G; Michelberger, P S; Champion, T F M; Reim, K F; Lee, K C; Sprague, M R; Jin, X-M; Langford, N K; Kolthammer, W S; Nunn, J; Walmsley, I A

2012-01-01

We demonstrate a dual-rail optical Raman memory inside a polarization interferometer; this enables us to store polarization-encoded information at GHz bandwidths in a room-temperature atomic ensemble. By performing full process tomography on the system, we measure up to 97 ± 1% process fidelity for the storage and retrieval process. At longer storage times, the process fidelity remains high, despite a loss of efficiency. The fidelity is 86 ± 4% for 1.5 μs storage time, which is 5000 times the pulse duration. Hence, high fidelity is combined with a large time-bandwidth product. This high performance, with an experimentally simple setup, demonstrates the suitability of the Raman memory for integration into large-scale quantum networks. (paper)

Upgrade of ATLAS ITk Pixel Detector

CERN Document Server

Huegging, Fabian; The ATLAS collaboration

2017-01-01

The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current inner detector will be replaced with an entirely-silicon inner tracker (ITk) which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels 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 and low mass global and local support structures. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the ITk ATLAS Pixel detector developments as well as different layout options will be reviewed.

NbN nanowire optical detectors for high speed applications

International Nuclear Information System (INIS)

Quaranta, O; Pagano, S; Ejrnaes, M; Nappi, C; Pessina, E; Fontana, F

2008-01-01

We have developed a novel geometry for single photon optical detectors (SSPD) based on NbN nanowires. Traditionally the SSPD are realized in a meander structure in order to realize a reasonable (few square microns) collecting area. This has the disadvantage of generating a large detector inductance, mostly of kinetic origin, that strongly limits the detector operation in high speed applications, such as telecommunication. Moreover the extreme aspect ratio of the detector (a nanowire a fraction of mm long and 100 nm wide) puts strong requirements on the nanofabrication processes, with negative effects on the production yield. Our novel proposed geometry is based on a parallel stripes configuration designed in such a way that the light induced switching of a single stripe generates the switching of all the other through a cascade mechanism. The net result is an SSPD device that has a much lower intrinsic inductance, and consequently a much wider bandwidth (up to 10 GHz range). Moreover the signal amplitude generated is much larger than that of traditional SSPD, due to the contribution of all the parallel stripe. We present here the design and results of numerical simulation of the response of this novel type of SSPD. In particular we discuss of the design solutions that allow the cascade operation of the detector, by realizing a very fast and synchronous switching of all the parallel lines. Key issues, such as the optimal number of parallel lines, with respect to fabrication and operation constraints of the detectors are also discussed

Development of a bandwidth limiting neutron chopper for CSNS

Science.gov (United States)

Wang, P.; Yang, B.; Cai, W. L.

2015-08-01

Bandwidth limiting neutron choppers are indispensable key equipments for the time-of-flight neutron scattering spectrometers of China Spallation Neutron Source (CSNS). The main principle is to chop the neutron beam to limit the neutron wavelength bandwidth at the neutron detector. We have successfully developed a bandwidth limiting neutron chopper for CSNS in the CSNS advance research project II. The transmission rate of the neutron absorbing coating is less than 1×10-4 (for 1 angstrom neutron). The phase control accuracy is ±0.084° (±9.4 μs at 25 Hz). The dynamic balance grade is G1.0. Various experimental technical features have met the design requirements, and it also runs stably and reliably during the long-term tests.

Development of a bandwidth limiting neutron chopper for CSNS

International Nuclear Information System (INIS)

Wang, P.; Yang, B.; Cai, W.L.

2015-01-01

Bandwidth limiting neutron choppers are indispensable key equipments for the time-of-flight neutron scattering spectrometers of China Spallation Neutron Source (CSNS). The main principle is to chop the neutron beam to limit the neutron wavelength bandwidth at the neutron detector. We have successfully developed a bandwidth limiting neutron chopper for CSNS in the CSNS advance research project II. The transmission rate of the neutron absorbing coating is less than 1×10 −4 (for 1 angstrom neutron). The phase control accuracy is ±0.084° (±9.4 μs at 25 Hz). The dynamic balance grade is G1.0. Various experimental technical features have met the design requirements, and it also runs stably and reliably during the long-term tests

Small-angle scattering of polychromatic X-rays: effects of bandwidth, spectral shape and high harmonics

Energy Technology Data Exchange (ETDEWEB)

Chen, Sen; Luo, Sheng-Nian

2018-02-16

Polychromatic X-ray sources can be useful for photon-starved small-angle X-ray scattering given their high spectral fluxes. Their bandwidths, however, are 10–100 times larger than those using monochromators. To explore the feasibility, ideal scattering curves of homogeneous spherical particles for polychromatic X-rays are calculated and analyzed using the Guinier approach, maximum entropy and regularization methods. Monodisperse and polydisperse systems are explored. The influence of bandwidth and asymmetric spectra shape are exploredviaGaussian and half-Gaussian spectra. Synchrotron undulator spectra represented by two undulator sources of the Advanced Photon Source are examined as an example, as regards the influence of asymmetric harmonic shape, fundamental harmonic bandwidth and high harmonics. The effects of bandwidth, spectral shape and high harmonics on particle size determination are evaluated quantitatively.

Small-angle scattering of polychromatic X-rays: effects of bandwidth, spectral shape and high harmonics.

Science.gov (United States)

Chen, Sen; Luo, Sheng Nian

2018-03-01

Polychromatic X-ray sources can be useful for photon-starved small-angle X-ray scattering given their high spectral fluxes. Their bandwidths, however, are 10-100 times larger than those using monochromators. To explore the feasibility, ideal scattering curves of homogeneous spherical particles for polychromatic X-rays are calculated and analyzed using the Guinier approach, maximum entropy and regularization methods. Monodisperse and polydisperse systems are explored. The influence of bandwidth and asymmetric spectra shape are explored via Gaussian and half-Gaussian spectra. Synchrotron undulator spectra represented by two undulator sources of the Advanced Photon Source are examined as an example, as regards the influence of asymmetric harmonic shape, fundamental harmonic bandwidth and high harmonics. The effects of bandwidth, spectral shape and high harmonics on particle size determination are evaluated quantitatively.

A wide-bandwidth and high-sensitivity robust microgyroscope

International Nuclear Information System (INIS)

Sahin, Korhan; Sahin, Emre; Akin, Tayfun; Alper, Said Emre

2009-01-01

This paper reports a microgyroscope design concept with the help of a 2 degrees of freedom (DoF) sense mode to achieve a wide bandwidth without sacrificing mechanical and electronic sensitivity and to obtain robust operation against variations under ambient conditions. The design concept is demonstrated with a tuning fork microgyroscope fabricated with an in-house silicon-on-glass micromachining process. When the fabricated gyroscope is operated with a relatively wide bandwidth of 1 kHz, measurements show a relatively high raw mechanical sensitivity of 131 µV (° s −1 ) −1 . The variation in the amplified mechanical sensitivity (scale factor) of the gyroscope is measured to be less than 0.38% for large ambient pressure variations such as from 40 to 500 mTorr. The bias instability and angle random walk of the gyroscope are measured to be 131° h −1 and 1.15° h −1/2 , respectively

Y-Ba-Cu-O thin films as high speed IR detectors

International Nuclear Information System (INIS)

Kwok, H.S.; Zheng, J.P.; Ying, Q.Y.

1990-01-01

Y-Ba-Cu-O thin film infrared detectors were fabricated and studied with various lasers. Operation of the detector in both the bolometric and nonbolometric modes was investigated at 10 microns with a CO2 laser. In the bolometric mode, the detectivity of the detector at 90 K was 2.1 x 10 to the 8th cm sq rt Hz/W with a response time of 15 microsec, corresponding to a bandwidth of 70 KHz. The speed of the detector in the nonbolometric mode was much faster and was beyond the instrument resolution. With a picosecond N2 laser, the output showed an instrument limited duration of 2 ns. The detectivity could not be determined in the nonbolometric mode due to the extremely low noise. The superconducting film quality is critical to the performance of these detectors. 27 refs

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.

Enhancement of sensitivity and bandwidth of gravitational wave detectors using fast-light-based white light cavities

International Nuclear Information System (INIS)

Salit, M; Shahriar, M S

2010-01-01

The effect of gravitational waves (GWs) has been observed indirectly, by monitoring the change in the orbital frequency of neutron stars in a binary system as they lose energy via gravitational radiation. However, GWs have not yet been observed directly. The initial LIGO apparatus has not yet observed GWs. The advanced LIGO (AdLIGO) will use a combination of improved techniques in order to increase the sensitivity. Along with power recycling and a higher power laser source, the AdLIGO will employ signal recycling (SR). While SR would increase sensitivity, it would also reduce the bandwidth significantly. Previously, we and others have investigated, theoretically and experimentally, the feasibility of using a fast-light-based white light cavity (WLC) to circumvent this constraint. However, in the previous work, it was not clear how one would incorporate the white light cavity effect. Here, we first develop a general model for Michelson-interferometer-based GW detectors that can be easily adapted to include the effects of incorporating a WLC into the design. We then describe a concrete design of a WLC constructed as a compound mirror, to replace the signal recycling mirror. This design is simple, robust, completely non-invasive, and can be added to the AdLIGO system without changing any other optical elements. We show a choice of parameters for which the signal sensitivity as well as the bandwidth are enhanced significantly over what is planned for the AdLIGO, covering the entire spectrum of interest for gravitational waves

Wide bandwidth transimpedance amplifier for extremely high sensitivity continuous measurements.

Science.gov (United States)

Ferrari, Giorgio; Sampietro, Marco

2007-09-01

This article presents a wide bandwidth transimpedance amplifier based on the series of an integrator and a differentiator stage, having an additional feedback loop to discharge the standing current from the device under test (DUT) to ensure an unlimited measuring time opportunity when compared to switched discharge configurations while maintaining a large signal amplification over the full bandwidth. The amplifier shows a flat response from 0.6 Hz to 1.4 MHz, the capability to operate with leakage currents from the DUT as high as tens of nanoamperes, and rail-to-rail dynamic range for sinusoidal current signals independent of the DUT leakage current. Also available is a monitor output of the stationary current to track experimental slow drifts. The circuit is ideal for noise spectral and impedance measurements of nanodevices and biomolecules when in the presence of a physiological medium and in all cases where high sensitivity current measurements are requested such as in scanning probe microscopy systems.

RAID Disk Arrays for High Bandwidth Applications

Science.gov (United States)

Moren, Bill

1996-01-01

High bandwidth applications require large amounts of data transferred to/from storage devices at extremely high data rates. Further, these applications often are 'real time' in which access to the storage device must take place on the schedule of the data source, not the storage. A good example is a satellite downlink - the volume of data is quite large and the data rates quite high (dozens of MB/sec). Further, a telemetry downlink must take place while the satellite is overhead. A storage technology which is ideally suited to these types of applications is redundant arrays of independent discs (RAID). Raid storage technology, while offering differing methodologies for a variety of applications, supports the performance and redundancy required in real-time applications. Of the various RAID levels, RAID-3 is the only one which provides high data transfer rates under all operating conditions, including after a drive failure.

High modulation bandwidth of a light-emitting diode with surface plasmon coupling (Conference Presentation)

Science.gov (United States)

Lin, Chun-Han; Tu, Charng-Gan; Yao, Yu-Feng; Chen, Sheng-Hung; Su, Chia-Ying; Chen, Hao-Tsung; Kiang, Yean-Woei; Yang, Chih-Chung

2017-02-01

Besides lighting, LEDs can be used for indoor data transmission. Therefore, a large modulation bandwidth becomes an important target in the development of visible LED. In this regard, enhancing the radiative recombination rate of carriers in the quantum wells of an LED is a useful method since the modulation bandwidth of an LED is related to the carrier decay rate besides the device RC time constant To increase the carrier decay rate in an LED without sacrificing its output power, the technique of surface plasmon (SP) coupling in an LED is useful. In this paper, the increases of modulation bandwidth by reducing mesa size, decreasing active layer thickness, and inducing SP coupling in blue- and green-emitting LEDs are illustrated. The results are demonstrated by comparing three different LED surface structures, including bare p-type surface, GaZnO current spreading layer, and Ag nanoparticles (NPs) for inducing SP coupling. In a single-quantum-well, blue-emitting LED with a circular mesa of 10 microns in radius, SP coupling results in a modulation bandwidth of 528.8 MHz, which is believed to be the record-high level. A smaller RC time constant can lead to a higher modulation bandwidth. However, when the RC time constant is smaller than 0.2 ns, its effect on modulation bandwidth saturates. The dependencies of modulation bandwidth on injected current density and carrier decay time confirm that the modulation bandwidth is essentially inversely proportional to a time constant, which is inversely proportional to the square-root of carrier decay rate and injected current density.

High-bandwidth and flexible tracking control for precision motion with application to a piezo nanopositioner.

Science.gov (United States)

Feng, Zhao; Ling, Jie; Ming, Min; Xiao, Xiao-Hui

2017-08-01

For precision motion, high-bandwidth and flexible tracking are the two important issues for significant performance improvement. Iterative learning control (ILC) is an effective feedforward control method only for systems that operate strictly repetitively. Although projection ILC can track varying references, the performance is still limited by the fixed-bandwidth Q-filter, especially for triangular waves tracking commonly used in a piezo nanopositioner. In this paper, a wavelet transform-based linear time-varying (LTV) Q-filter design for projection ILC is proposed to compensate high-frequency errors and improve the ability to tracking varying references simultaneously. The LVT Q-filter is designed based on the modulus maximum of wavelet detail coefficients calculated by wavelet transform to determine the high-frequency locations of each iteration with the advantages of avoiding cross-terms and segmenting manually. The proposed approach was verified on a piezo nanopositioner. Experimental results indicate that the proposed approach can locate the high-frequency regions accurately and achieve the best performance under varying references compared with traditional frequency-domain and projection ILC with a fixed-bandwidth Q-filter, which validates that through implementing the LTV filter on projection ILC, high-bandwidth and flexible tracking can be achieved simultaneously by the proposed approach.

Ultra-low Noise, High Bandwidth, 1550nm HgCdTe APD, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — To meet the demands of future high-capacity free space optical communications links, a high bandwidth, near infrared (NIR), single photon sensitive optoelectronic...

Bandwidth-limited control and ringdown suppression in high-Q resonators.

Science.gov (United States)

Borneman, Troy W; Cory, David G

2012-12-01

We describe how the transient behavior of a tuned and matched resonator circuit and a ringdown suppression pulse may be integrated into an optimal control theory (OCT) pulse-design algorithm to derive control sequences with limited ringdown that perform a desired quantum operation in the presence of resonator distortions of the ideal waveform. Inclusion of ringdown suppression in numerical pulse optimizations significantly reduces spectrometer deadtime when using high quality factor (high-Q) resonators, leading to increased signal-to-noise ratio (SNR) and sensitivity of inductive measurements. To demonstrate the method, we experimentally measure the free-induction decay of an inhomogeneously broadened solid-state free radical spin system at high Q. The measurement is enabled by using a numerically optimized bandwidth-limited OCT pulse, including ringdown suppression, robust to variations in static and microwave field strengths. We also discuss the applications of pulse design in high-Q resonators to universal control of anisotropic-hyperfine coupled electron-nuclear spin systems via electron-only modulation even when the bandwidth of the resonator is significantly smaller than the hyperfine coupling strength. These results demonstrate how limitations imposed by linear response theory may be vastly exceeded when using a sufficiently accurate system model to optimize pulses of high complexity. Copyright © 2012 Elsevier Inc. All rights reserved.

GHz-bandwidth upconversion detector using a unidirectional ring cavity to reduce multilongitudinal mode pump effects

DEFF Research Database (Denmark)

Meng, Lichun; Høgstedt, Lasse; Tidemand-Lichtenberg, Peter

2017-01-01

We demonstrate efficient upconversion of modulated infrared (IR) signals over a wide bandwidth (up to frequencies in excess of 1 GHz) via cavity-enhanced sum-frequency generation (SFG) in a periodically poled LiNbO3. Intensity modulated IR signal is produced by combining beams from two 1547 nm...... narrow-linewidth lasers in a fiber coupler while tuning their wavelength difference down to 10 pm or less. The SFG crystal is placed inside an Nd:YVO4 ring cavity that provides 1064 nm circulating pump powers of up to 150 W in unidirectional operation. Measured Fabry-Perot spectrum at 1064 nm confirms...... the enhanced spectral stability from multiple to single longitudinal mode pumping condition. We describe analytically and demonstrate experimentally the deleterious effects of using a multimode pump to the high-bandwidth RF spectrum of the 630 nm SFG output. Offering enhanced sensitivity without the need...

Review of single transient oscillographic recorders with gigahertz bandwidth

International Nuclear Information System (INIS)

Campbell, D.E.

1982-01-01

In laser driven inertial confinement fusion research, at Livermore, we are diagnosing many phenomena that occur in a time frame that exceeds the capabilities of even the most advanced, present day oscillographic recording instruments. Many of the by-products of the interaction between the laser beam and fuel pellet are monitored to determine the specifics of the fusion process. By the use of appropriate detectors, we convert the information contained in the radiated by-products to electrical signals which are recorded on high bandwidth oscillographic recorders. Our present range of recording capabilities for one x-ray diagnostic measurement in use at Livermore is shown. A commonly used configuration consists of an XRD-31 x-ray detector connected to a direct access Tektronix R7912 transient digitizer using 1/2 in. diameter air dielectric coaxial cable. This configuration gives a system fwhm of approximately 335 ps. Our premier configuration, on the other hand, consists of an improved response detector and a French Thomson-CSF TSN-660 oscilloscope with a shorter length of coaxial cable (typically 20 feet). The system fwhm in this case is less than 120 ps which is our fastest oscillographic recording system at the present time

High-Bandwidth Dynamic Full-Field Profilometry for Nano-Scale Characterization of MEMS

International Nuclear Information System (INIS)

Chen, L-C; Huang, Y-T; Chang, P-B

2006-01-01

The article describes an innovative optical interferometric methodology to delivery dynamic surface profilometry with a measurement bandwidth up to 10MHz or higher and a vertical resolution up to 1 nm. Previous work using stroboscopic microscopic interferometry for dynamic characterization of micro (opto)electromechanical systems (M(O)EMS) has been limited in measurement bandwidth mainly within a couple of MHz. For high resonant mode analysis, the stroboscopic light pulse is insufficiently short to capture the moving fringes from dynamic motion of the detected structure. In view of this need, a microscopic prototype based on white-light stroboscopic interferometry with an innovative light superposition strategy was developed to achieve dynamic full-field profilometry with a high measurement bandwidth up to 10MHz or higher. The system primarily consists of an optical microscope, on which a Mirau interferometric objective embedded with a piezoelectric vertical translator, a high-power LED light module with dual operation modes and light synchronizing electronics unit are integrated. A micro cantilever beam used in AFM was measured to verify the system capability in accurate characterisation of dynamic behaviours of the device. The full-field seventh-mode vibration at a vibratory frequency of 3.7MHz can be fully characterized and nano-scale vertical measurement resolution as well as tens micrometers of vertical measurement range can be performed

High-Bandwidth Dynamic Full-Field Profilometry for Nano-Scale Characterization of MEMS

Energy Technology Data Exchange (ETDEWEB)

Chen, L-C [Graduate Institute of Automation Technology, National Taipei University of Technology, 1 Sec. 3 Chung-Hsiao East Rd., Taipei, 106, Taiwan (China); Huang, Y-T [Graduate Institute of Automation Technology, National Taipei University of Technology, 1 Sec. 3 Chung-Hsiao East Rd., Taipei, 106, Taiwan (China); Chang, P-B [Graduate Institute of Mechanical and Electrical Engineering, National Taipei University of Technology, 1 Sec. 3 Chung-Hsiao East Rd., Taipei, 106, Taiwan (China)

2006-10-15

The article describes an innovative optical interferometric methodology to delivery dynamic surface profilometry with a measurement bandwidth up to 10MHz or higher and a vertical resolution up to 1 nm. Previous work using stroboscopic microscopic interferometry for dynamic characterization of micro (opto)electromechanical systems (M(O)EMS) has been limited in measurement bandwidth mainly within a couple of MHz. For high resonant mode analysis, the stroboscopic light pulse is insufficiently short to capture the moving fringes from dynamic motion of the detected structure. In view of this need, a microscopic prototype based on white-light stroboscopic interferometry with an innovative light superposition strategy was developed to achieve dynamic full-field profilometry with a high measurement bandwidth up to 10MHz or higher. The system primarily consists of an optical microscope, on which a Mirau interferometric objective embedded with a piezoelectric vertical translator, a high-power LED light module with dual operation modes and light synchronizing electronics unit are integrated. A micro cantilever beam used in AFM was measured to verify the system capability in accurate characterisation of dynamic behaviours of the device. The full-field seventh-mode vibration at a vibratory frequency of 3.7MHz can be fully characterized and nano-scale vertical measurement resolution as well as tens micrometers of vertical measurement range can be performed.

Fast Faraday Cup With High Bandwidth

Science.gov (United States)

Deibele, Craig E [Knoxville, TN

2006-03-14

A circuit card stripline Fast Faraday cup quantitatively measures the picosecond time structure of a charged particle beam. The stripline configuration maintains signal integrity, and stitching of the stripline increases the bandwidth. A calibration procedure ensures the measurement of the absolute charge and time structure of the charged particle beam.

Note: Expanding the bandwidth of the ultra-low current amplifier using an artificial negative capacitor

Energy Technology Data Exchange (ETDEWEB)

Xie, Kai, E-mail: kaixie@mail.xidian.edu.cn; Liu, Yan; Li, XiaoPing [School of Aerospace Science and Technology, Xidian University, Xi’an 710071 (China); Guo, Lixin [School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071 (China); Zhang, Hanlu [School of Communication & Information Engineering, Xi’an University of Posts & Telecommunication, Xi’an 710121 (China)

2016-04-15

The bandwidth and low noise characteristics are often contradictory in ultra-low current amplifier, because an inevitable parasitic capacitance is paralleled with the high value feedback resistor. In order to expand the amplifier’s bandwidth, a novel approach was proposed by introducing an artificial negative capacitor to cancel the parasitic capacitance. The theory of the negative capacitance and the performance of the improved amplifier circuit with the negative capacitor are presented in this manuscript. The test was conducted by modifying an ultra-low current amplifier with a trans-impedance gain of 50 GΩ. The results show that the maximum bandwidth was expanded from 18.7 Hz to 3.3 kHz with more than 150 times of increase when the parasitic capacitance (∼0.17 pF) was cancelled. Meanwhile, the rise time decreased from 18.7 ms to 0.26 ms with no overshot. Any desired bandwidth or rise time within these ranges can be obtained by adjusting the ratio of cancellation of the parasitic and negative capacitance. This approach is especially suitable for the demand of rapid response to weak current, such as transient ion-beam detector, mass spectrometry analysis, and fast scanning microscope.

Note: Expanding the bandwidth of the ultra-low current amplifier using an artificial negative capacitor.

Science.gov (United States)

Xie, Kai; Liu, Yan; Li, XiaoPing; Guo, Lixin; Zhang, Hanlu

2016-04-01

The bandwidth and low noise characteristics are often contradictory in ultra-low current amplifier, because an inevitable parasitic capacitance is paralleled with the high value feedback resistor. In order to expand the amplifier's bandwidth, a novel approach was proposed by introducing an artificial negative capacitor to cancel the parasitic capacitance. The theory of the negative capacitance and the performance of the improved amplifier circuit with the negative capacitor are presented in this manuscript. The test was conducted by modifying an ultra-low current amplifier with a trans-impedance gain of 50 GΩ. The results show that the maximum bandwidth was expanded from 18.7 Hz to 3.3 kHz with more than 150 times of increase when the parasitic capacitance (∼0.17 pF) was cancelled. Meanwhile, the rise time decreased from 18.7 ms to 0.26 ms with no overshot. Any desired bandwidth or rise time within these ranges can be obtained by adjusting the ratio of cancellation of the parasitic and negative capacitance. This approach is especially suitable for the demand of rapid response to weak current, such as transient ion-beam detector, mass spectrometry analysis, and fast scanning microscope.

A Highly Sensitive Multi-Element HgCdTe E-APD Detector for IPDA Lidar Applications

Science.gov (United States)

Beck, Jeff; Welch, Terry; Mitra, Pradip; Reiff, Kirk; Sun, Xiaoli; Abshire, James

2014-01-01

An HgCdTe electron avalanche photodiode (e-APD) detector has been developed for lidar receivers, one application of which is integrated path differential absorption lidar measurements of such atmospheric trace gases as CO2 and CH4. The HgCdTe APD has a wide, visible to mid-wave-infrared, spectral response, high dynamic range, substantially improved sensitivity, and an expected improvement in operational lifetime. A demonstration sensor-chip assembly consisting of a 4.3 lm cutoff HgCdTe 4 9 4 APD detector array with 80 micrometer pitch pixels and a custom complementary metal-oxide-semiconductor readout integrated circuit was developed. For one typical array the APD gain was 654 at 12 V with corresponding gain normalized dark currents ranging from 1.2 fA to 3.2 fA. The 4 9 4 detector system was characterized at 77 K with a 1.55 micrometer wavelength, 1 microsecond wide, laser pulse. The measured unit gain detector photon conversion efficiency was 91.1%. At 11 V bias the mean measured APD gain at 77 K was 307.8 with sigma/mean uniformity of 1.23%. The average, noise-bandwidth normalized, system noise-equivalent power (NEP) was 1.04 fW/Hz(exp 1/2) with a sigma/mean of 3.8%. The measured, electronics-limited, bandwidth of 6.8 MHz was more than adequate for 1 microsecond pulse detection. The system had an NEP (3 MHz) of 0.4 fW/Hz(exp 1/2) at 12 V APD bias and a linear dynamic range close to 1000. A gain-independent quantum-limited SNR of 80% of full theoretical was indicative of a gain-independent excess noise factor very close to 1.0 and the expected APD mode quantum efficiency.

High bandwidth second-harmonic generation in partially deuterated KDP

International Nuclear Information System (INIS)

Webb, M.S.; Eimerl, D.; Velsko, S.P.

1992-01-01

We have experimentally determined the spectrally noncritical phasematching behavior of Type I frequency doubling in KDP and its dependence on deuteration level in partially deuterated KDP. The first order wavelength sensitivity parameter∂Δk/∂γ for Type I doubling of 1.053 μm light vanishes for a KD*P crystal with a deuteration level between 10 and 14%. Very high bandwidth frequency doubling of Nd:glass lasers is possible with such a crystal

VLSI Implementation of a Fixed-Complexity Soft-Output MIMO Detector for High-Speed Wireless

Directory of Open Access Journals (Sweden)

Di Wu

2010-01-01

Full Text Available This paper presents a low-complexity MIMO symbol detector with close-Maximum a posteriori performance for the emerging multiantenna enhanced high-speed wireless communications. The VLSI implementation is based on a novel MIMO detection algorithm called Modified Fixed-Complexity Soft-Output (MFCSO detection, which achieves a good trade-off between performance and implementation cost compared to the referenced prior art. By including a microcode-controlled channel preprocessing unit and a pipelined detection unit, it is flexible enough to cover several different standards and transmission schemes. The flexibility allows adaptive detection to minimize power consumption without degradation in throughput. The VLSI implementation of the detector is presented to show that real-time MIMO symbol detection of 20 MHz bandwidth 3GPP LTE and 10 MHz WiMAX downlink physical channel is achievable at reasonable silicon cost.

High efficiency and broad bandwidth grating coupler between nanophotonic waveguide and fibre

International Nuclear Information System (INIS)

Yu, Zhu; Xue-Jun, Xu; Zhi-Yong, Li; Liang, Zhou; Yu-De, Yu; Jin-Zhong, Yu; Wei-Hua, Han; Zhong-Chao, Fan

2010-01-01

A high efficiency and broad bandwidth grating coupler between a silicon-on-insulator (SOI) nanophotonic waveguide and fibre is designed and fabricated. Coupling efficiencies of 46% and 25% at a wavelength of 1.55 μm are achieved by simulation and experiment, respectively. An optical 3 dB bandwidth of 45 nm from 1530 nm to 1575 nm is also obtained in experiment. Numerical calculation shows that a tolerance to fabrication error of 10 nm in etch depth is achievable. The measurement results indicate that the alignment error of ±2 μm results in less than 1 dB additional coupling loss. (classical areas of phenomenology)

High-Q Variable Bandwidth Passive Filters for Software Defined Radio

NARCIS (Netherlands)

Arkesteijn, V.J.; Klumperink, Eric A.M.; Nauta, Bram

2001-01-01

An important aspect of Software Defined Radio is the ability to define the bandwidth of the filter that selects the desired channel. This paper describes a technique for channel filtering, in which two passive filters are combined to obtain a variable bandwidth. Passive filters have the advantage of

High-Q variable bandwidth passive filters for Software Defined Radio

NARCIS (Netherlands)

Arkesteijn, V.J.; Klumperink, Eric A.M.; Nauta, Bram

An important aspect of Software Defined Radio is the ability to define the bandwidth of the filter that selects the desired channel. This paper describes a technique for channel filtering, in which two passive filters are combined to obtain a variable bandwidth. Passive filters have the advantage of

Bandwidths of micro-twisted-pair cables and fusion-spliced SIMM-GRIN fiber

International Nuclear Information System (INIS)

Gan, K.K.; Kagan, H.P.; Kass, R.D.; Smith, D.S.

2007-01-01

The SLHC is designed to increase the luminosity of the LHC by a factor of 10. In the present ATLAS pixel detector, electrical signals between the pixel modules and the optical modules (opto-boards) are transmitted in ∼1 m of micro-twisted-pair cables. The optical signals between the opto-boards and the off-detector optical modules are transmitted in fiber ribbons. Each fiber link consists of 8 m of rad-hard/low bandwidth SIMM fiber fusion spliced to 70 m of rad-tolerant/medium bandwidth GRIN fiber. We currently transmit optical signals at 80 Mb/s and expect to transmit signals at 1 Gb/s in the SLHC. For the SLHC optical link, we would like to take advantage of some of the design features of the present pixel optical links and the many years of R and D effort and production experience. If the present architecture can transmit signals at the higher speed required by the SLHC, the constraint of requiring no extra service space is automatically satisfied. We have measured the bandwidths of the transmission lines and our preliminary results indicate that the micro-twisted-pair cables can transmit signals up to ∼1 Gb/s and the fusion-spliced fiber ribbon can transmit signals up to ∼2 Gb/s

An acquisition system for CMOS imagers with a genuine 10 Gbit/s bandwidth

International Nuclear Information System (INIS)

Guérin, C.; Mahroug, J.; Tromeur, W.; Houles, J.; Calabria, P.; Barbier, R.

2012-01-01

This paper presents a high data throughput acquisition system for pixel detector readout such as CMOS imagers. This CMOS acquisition board offers a genuine 10 Gbit/s bandwidth to the workstation and can provide an on-line and continuous high frame rate imaging capability. On-line processing can be implemented either on the Data Acquisition Board or on the multi-cores workstation depending on the complexity of the algorithms. The different parts composing the acquisition board have been designed to be used first with a single-photon detector called LUSIPHER (800×800 pixels), developed in our laboratory for scientific applications ranging from nano-photonics to adaptive optics. The architecture of the acquisition board is presented and the performances achieved by the produced boards are described. The future developments (hardware and software) concerning the on-line implementation of algorithms dedicated to single-photon imaging are tackled.

High-speed readout of high-Z pixel detectors with the LAMBDA detector

International Nuclear Information System (INIS)

Pennicard, D.; Smoljanin, S.; Sheviakov, I.; Xia, Q.; Rothkirch, A.; Yu, Y.; Struth, B.; Hirsemann, H.; Graafsma, H.

2014-01-01

High-frame-rate X-ray pixel detectors make it possible to perform time-resolved experiments at synchrotron beamlines, and to make better use of these sources by shortening experiment times. LAMBDA is a photon-counting hybrid pixel detector based on the Medipix3 chip, designed to combine a small pixel size of 55 μm, a large tileable module design, high speed, and compatibility with ''high-Z'' sensors for hard X-ray detection. This technical paper focuses on LAMBDA's high-speed-readout functionality, which allows a frame rate of 2000 frames per second with no deadtime between successive images. This takes advantage of the Medipix3 chip's ''continuous read-write'' function and highly parallelised readout. The readout electronics serialise this data and send it back to a server PC over two 10 Gigabit Ethernet links. The server PC controls the detector and receives, processes and stores the data using software designed for the Tango control system. As a demonstration of high-speed readout of a high-Z sensor, a GaAs LAMBDA detector was used to make a high-speed X-ray video of a computer fan

A High Gain-Bandwidth Product Distributed Transimpedance Amplifier IC for High-Speed Optical Transmission Using Low-Cost GaAs Technology.

OpenAIRE

Giannini, F.; Limiti, E.; Orengo, G.; Serino, A.; De Dominicis, M.

2002-01-01

This paper reports a distributed baseband transimpedance amplifier for optical links up to 10 Gb/s. The amplifier operates as a baseband amplifier with a transimpedance gain of 48 dB Ω and a DC-to-9 GHz bandwidth. Some innovative design techniques to improve gain-bandwidth performance at low and high frequency with an available low-cost GaAs MESFET technology have been developed.

Highly-Integrated Hydraulic Smart Actuators and Smart Manifolds for High-Bandwidth Force Control

Directory of Open Access Journals (Sweden)

Victor Barasuol

2018-06-01

Full Text Available Hydraulic actuation is the most widely used alternative to electric motors for legged robots and manipulators. It is often selected for its high power density, robustness and high-bandwidth control performance that allows the implementation of force/impedance control. Force control is crucial for robots that are in contact with the environment, since it enables the implementation of active impedance and whole body control that can lead to a better performance in known and unknown environments. This paper presents the hydraulic Integrated Smart Actuator (ISA developed by Moog in collaboration with IIT, as well as smart manifolds for rotary hydraulic actuators. The ISA consists of an additive-manufactured body containing a hydraulic cylinder, servo valve, pressure/position/load/temperature sensing, overload protection and electronics for control and communication. The ISA v2 and ISA v5 have been specifically designed to fit into the legs of IIT’s hydraulic quadruped robots HyQ and HyQ-REAL, respectively. The key features of these components tackle 3 of today’s main challenges of hydraulic actuation for legged robots through: (1 built-in controllers running inside integrated electronics for high-performance control, (2 low-leakage servo valves for reduced energy losses, and (3 compactness thanks to metal additive manufacturing. The main contributions of this paper are the derivation of the representative dynamic models of these highly integrated hydraulic servo actuators, a control architecture that allows for high-bandwidth force control and their experimental validation with application-specific trajectories and tests. We believe that this is the first work that presents additive-manufactured, highly integrated hydraulic smart actuators for robotics.

Three-Axis Attitude Estimation With a High-Bandwidth Angular Rate Sensor

Science.gov (United States)

Bayard, David S.; Green, Joseph J.

2013-01-01

A continuing challenge for modern instrument pointing control systems is to meet the increasingly stringent pointing performance requirements imposed by emerging advanced scientific, defense, and civilian payloads. Instruments such as adaptive optics telescopes, space interferometers, and optical communications make unprecedented demands on precision pointing capabilities. A cost-effective method was developed for increasing the pointing performance for this class of NASA applications. The solution was to develop an attitude estimator that fuses star tracker and gyro measurements with a high-bandwidth angular rotation sensor (ARS). An ARS is a rate sensor whose bandwidth extends well beyond that of the gyro, typically up to 1,000 Hz or higher. The most promising ARS sensor technology is based on a magnetohydrodynamic concept, and has recently become available commercially. The key idea is that the sensor fusion of the star tracker, gyro, and ARS provides a high-bandwidth attitude estimate suitable for supporting pointing control with a fast-steering mirror or other type of tip/tilt correction for increased performance. The ARS is relatively inexpensive and can be bolted directly next to the gyro and star tracker on the spacecraft bus. The high-bandwidth attitude estimator fuses an ARS sensor with a standard three-axis suite comprised of a gyro and star tracker. The estimation architecture is based on a dual-complementary filter (DCF) structure. The DCF takes a frequency- weighted combination of the sensors such that each sensor is most heavily weighted in a frequency region where it has the lowest noise. An important property of the DCF is that it avoids the need to model disturbance torques in the filter mechanization. This is important because the disturbance torques are generally not known in applications. This property represents an advantage over the prior art because it overcomes a weakness of the Kalman filter that arises when fusing more than one rate

High-speed 405-nm superluminescent diode (SLD) with 807-MHz modulation bandwidth

KAUST Repository

Shen, Chao

2016-08-25

III-nitride LEDs are fundamental components for visible-light communication (VLC). However, the modulation bandwidth is inherently limited by the relatively long carrier lifetime. In this letter, we present the 405 nm emitting superluminescent diode (SLD) with tilted facet design on semipolar GaN substrate, showing a broad emission of ∼9 nm at 20 mW optical power. Owing to the fast recombination (τ<0.35 ns) through the amplified spontaneous emission, the SLD exhibits a significantly large 3-dB bandwidth of 807 MHz. A data rate of 1.3 Gbps with a bit-error rate of 2.9 × 10 was obtained using on-off keying modulation scheme, suggesting the SLD being a high-speed transmitter for VLC applications.

High-speed 405-nm superluminescent diode (SLD) with 807-MHz modulation bandwidth

KAUST Repository

Shen, Chao; Lee, Changmin; Ng, Tien Khee; Nakamura, Shuji; Speck, James S.; DenBaars, Steven P.; Alyamani, Ahmed Y.; El-Desouki, Munir M.; Ooi, Boon S.

2016-01-01

III-nitride LEDs are fundamental components for visible-light communication (VLC). However, the modulation bandwidth is inherently limited by the relatively long carrier lifetime. In this letter, we present the 405 nm emitting superluminescent diode (SLD) with tilted facet design on semipolar GaN substrate, showing a broad emission of ∼9 nm at 20 mW optical power. Owing to the fast recombination (τ<0.35 ns) through the amplified spontaneous emission, the SLD exhibits a significantly large 3-dB bandwidth of 807 MHz. A data rate of 1.3 Gbps with a bit-error rate of 2.9 × 10 was obtained using on-off keying modulation scheme, suggesting the SLD being a high-speed transmitter for VLC applications.

New Generation of Superconducting Nanowire Single-Photon Detectors

Directory of Open Access Journals (Sweden)

Goltsman G.N.

2015-01-01

Full Text Available We present an overview of recent results for new generation of infrared and optical superconducting nanowire single-photon detectors (SNSPDs that has already demonstrated a performance that makes them devices-of-choice for many applications. SNSPDs provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, SNSPDs are also compatible with an integrated optical platform as a crucial requirement for applications in emerging quantum photonic technologies. By embedding SNSPDs in nanophotonic circuits we realize waveguide integrated single photon detectors which unite all desirable detector properties in a single device.

A frequency and sensitivity tunable microresonator array for high-speed quantum processor readout

Energy Technology Data Exchange (ETDEWEB)

Whittaker, J. D., E-mail: jwhittaker@dwavesys.com; Swenson, L. J.; Volkmann, M. H.; Spear, P.; Altomare, F.; Berkley, A. J.; Bunyk, P.; Harris, R.; Hilton, J. P.; Hoskinson, E.; Johnson, M. W.; Ladizinsky, E.; Lanting, T.; Oh, T.; Perminov, I.; Tolkacheva, E.; Yao, J. [D-Wave Systems, Inc., Burnaby, British Columbia V5G 4M9 (Canada); Bumble, B.; Day, P. K.; Eom, B. H. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); and others

2016-01-07

Superconducting microresonators have been successfully utilized as detection elements for a wide variety of applications. With multiplexing factors exceeding 1000 detectors per transmission line, they are the most scalable low-temperature detector technology demonstrated to date. For high-throughput applications, fewer detectors can be coupled to a single wire but utilize a larger per-detector bandwidth. For all existing designs, fluctuations in fabrication tolerances result in a non-uniform shift in resonance frequency and sensitivity, which ultimately limits the efficiency of bandwidth utilization. Here, we present the design, implementation, and initial characterization of a superconducting microresonator readout integrating two tunable inductances per detector. We demonstrate that these tuning elements provide independent control of both the detector frequency and sensitivity, allowing us to maximize the transmission line bandwidth utilization. Finally, we discuss the integration of these detectors in a multilayer fabrication stack for high-speed readout of the D-Wave quantum processor, highlighting the use of control and routing circuitry composed of single-flux-quantum loops to minimize the number of control wires at the lowest temperature stage.

Pickup design for high bandwidth bunch arrival-time monitors in free-electron lasers

Energy Technology Data Exchange (ETDEWEB)

Angelovski, Aleksandar; Penirschke, Andreas; Jakoby, Rolf [TU Darmstadt (Germany). Institut fuer Mikrowellentechnik und Photonik; Kuhl, Alexander; Schnepp, Sascha [TU Darmstadt (Germany). Graduate School of Computational Engineering; Bock, Marie Kristin; Bousonville, Michael; Schlarb, Holger [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Weiland, Thomas [TU Darmstadt (Germany). Institut fuer Theorie Elektromagnetischer Felder

2012-07-01

The increased demands for low bunch charge operation mode in the free-electron lasers (FELs) require an upgrade of the existing synchronization equipment. As a part of the laser-based synchronization system, the bunch arrival-time monitors (BAMs) should have a sub-10 femtosecond precision for high and low bunch charge operation. In order to fulfill the resolution demands for both modes of operation, the bandwidth of such a BAM should be increased up to a cutoff frequency of 40 GHz. In this talk, we present the design and the realization of high bandwidth cone-shaped pickup electrodes as a part of the BAM for the FEL in Hamburg (FLASH) and the European X-ray free-electron laser (European XFEL). The proposed pickup was simulated with CST STUDIO SUITE, and a non-hermetic model was built up for radio frequency (rf) measurements.

Applied techniques for high bandwidth data transfers across wide area networks

International Nuclear Information System (INIS)

Lee, J.; Gunter, D.; Tierney, B.; Allcock, B.; Bester, J.; Bresnahan, J.; Tuecke, S.

2001-01-01

Large distributed systems such as Computational/Data Grids require large amounts of data to be co-located with the computing facilities for processing. From their work developing a scalable distributed network cache, the authors have gained experience with techniques necessary to achieve high data throughput over high bandwidth Wide Area Networks (WAN). The authors discuss several hardware and software design techniques, and then describe their application to an implementation of an enhanced FTP protocol called GridFTP. The authors describe results from the Supercomputing 2000 conference

Performance of the inverse photoemission spectrometer with a new bandpass photon detector of narrow bandwidth and high sensitivity

International Nuclear Information System (INIS)

Ueda, Yoshifumi; Nishihara, Katsuhiro; Mimura, Kojiro; Hari, Yasuko; Taniguchi, Masaki; Fujisawa, Masami

1993-01-01

A combination of a SrF 2 entrance window and a photomultiplier with the Cu-BeO first dynode coated with KCl film realizes the bandpass photon detector with the FWHM of 0.47 eV centered at 9.43 eV and the sensitivity improved by about one order of magnitude in comparison with the detector without the KCl film. The overall energy resolution of the inverse photoemission spectrometer consisting of an electron gun with a BaO cathode and the new detector has been estimated to be 0.56 eV using polycrystalline Au. Typical counting rate is 10 2 -10 3 counts/(μA s) for unoccupied states near the Fermi level of the Au at an acceptance angle of about 0.8π sr with an Al collecting mirror. (orig.)

The effect of extending high-frequency bandwidth on the acceptable noise level (ANL) of hearing-impaired listeners.

Science.gov (United States)

Johnson, Earl; Ricketts, Todd; Hornsby, Benjamin

2009-01-01

This study examined the effects of extending high-frequency bandwidth, for both a speech signal and a background noise, on the acceptable signal-to-noise ratio (SNR) of listeners with mild sensorineural hearing loss through utilization of the Acceptable Noise Level (ANL) procedure. In addition to extending high-frequency bandwidth, the effects of reverberation time and background noise type and shape were also examined. The study results showed a significant increase in the mean ANL (i.e. participants requested a better SNR for an acceptable listening situation) when high-frequency bandwidth was extended from 3 to 9 kHz and from 6 to 9 kHz. No change in the ANL of study participants was observed as a result of isolated modification to reverberation time or background noise stimulus. An interaction effect, however, of reverberation time and background noise stimulus was demonstrated. These findings may have implications for future design of hearing aid memory programs for listening to speech in the presence of broadband background noise.

Response of resonant gravitational wave detectors to damped sinusoid signals

International Nuclear Information System (INIS)

Pai, A; Celsi, C; Pallottino, G V; D'Antonio, S; Astone, P

2007-01-01

Till date, the search for burst signals with resonant gravitational wave (GW) detectors has been done using the δ-function approximation for the signal, which was reasonable due to the very small bandwidth of these detectors. However, now with increased bandwidth (of the order of 10 or more Hz) and with the possibility of comparing results with interferometric GW detectors (broad-band), it is very important to exploit the resonant detectors' capability to detect also signals with specific wave shapes. As a first step, we present a study of the response of resonant GW detectors to damped sinusoids with given frequency and decay time and report on the development of a filter matched to these signals. This study is a preliminary step towards the comprehension of the detector response and of the filtering for signals such as the excitation of stellar quasi-normal modes

Bandwidth extension of speech using perceptual criteria

CERN Document Server

Berisha, Visar; Liss, Julie

2013-01-01

Bandwidth extension of speech is used in the International Telecommunication Union G.729.1 standard in which the narrowband bitstream is combined with quantized high-band parameters. Although this system produces high-quality wideband speech, the additional bits used to represent the high band can be further reduced. In addition to the algorithm used in the G.729.1 standard, bandwidth extension methods based on spectrum prediction have also been proposed. Although these algorithms do not require additional bits, they perform poorly when the correlation between the low and the high band is weak. In this book, two wideband speech coding algorithms that rely on bandwidth extension are developed. The algorithms operate as wrappers around existing narrowband compression schemes. More specifically, in these algorithms, the low band is encoded using an existing toll-quality narrowband system, whereas the high band is generated using the proposed extension techniques. The first method relies only on transmitted high-...

Ultra-wide frequency response measurement of an optical system with a DC photo-detector

KAUST Repository

Kuntz, Katanya B.; Wheatley, Trevor A.; Song, Hongbin; Webb, James G.; Mabrok, Mohamed; Huntington, Elanor H.; Yonezawa, Hidehiro

2017-01-01

Precise knowledge of an optical device's frequency response is crucial for it to be useful in most applications. Traditional methods for determining the frequency response of an optical system (e.g. optical cavity or waveguide modulator) usually rely on calibrated broadband photo-detectors or complicated RF mixdown operations. As the bandwidths of these devices continue to increase, there is a growing need for a characterization method that does not have bandwidth limitations, or require a previously calibrated device. We demonstrate a new calibration technique on an optical system (consisting of an optical cavity and a high-speed waveguide modulator) that is free from limitations imposed by detector bandwidth, and does not require a calibrated photo-detector or modulator. We use a low-frequency (DC) photo-detector to monitor the cavity's optical response as a function of modulation frequency, which is also used to determine the modulator's frequency response. Knowledge of the frequency-dependent modulation depth allows us to more precisely determine the cavity's characteristics (free spectral range and linewidth). The precision and repeatability of our technique is demonstrated by measuring the different resonant frequencies of orthogonal polarization cavity modes caused by the presence of a non-linear crystal. Once the modulator has been characterized using this simple method, the frequency response of any passive optical element can be determined to a fine resolution (e.g. kilohertz) over several gigahertz.

Status of the CMS Phase I pixel detector upgrade

Energy Technology Data Exchange (ETDEWEB)

Spannagel, S., E-mail: simon.spannagel@desy.de

2016-09-21

A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

Status of the CMS Phase I Pixel Detector Upgrade

CERN Document Server

Spannagel, Simon

2016-09-21

A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase~I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

High Dielectric Low Loss Transparent Glass Material Based Dielectric Resonator Antenna with Wide Bandwidth Operation

Science.gov (United States)

Mehmood, Arshad; Zheng, Yuliang; Braun, Hubertus; Hovhannisyan, Martun; Letz, Martin; Jakoby, Rolf

2015-01-01

This paper presents the application of new high permittivity and low loss glass material for antennas. This glass material is transparent. A very simple rectangular dielectric resonator antenna is designed first with a simple microstrip feeding line. In order to widen the bandwidth, the feed of the design is modified by forming a T-shaped feeding. This new design enhanced the bandwidth range to cover the WLAN 5 GHz band completely. The dielectric resonator antenna cut into precise dimensions is placed on the modified microstrip feed line. The design is simple and easy to manufacture and also very compact in size of only 36 × 28 mm. A -10 dB impedance bandwidth of 18% has been achieved, which covers the frequency range from 5.15 GHz to 5.95 GHz. Simulations of the measured return loss and radiation patterns are presented and discussed.

Bandwidth efficient coding

CERN Document Server

Anderson, John B

2017-01-01

Bandwidth Efficient Coding addresses the major challenge in communication engineering today: how to communicate more bits of information in the same radio spectrum. Energy and bandwidth are needed to transmit bits, and bandwidth affects capacity the most. Methods have been developed that are ten times as energy efficient at a given bandwidth consumption as simple methods. These employ signals with very complex patterns and are called "coding" solutions. The book begins with classical theory before introducing new techniques that combine older methods of error correction coding and radio transmission in order to create narrowband methods that are as efficient in both spectrum and energy as nature allows. Other topics covered include modulation techniques such as CPM, coded QAM and pulse design.

High-Resolution PET Detector. Final report

International Nuclear Information System (INIS)

Karp, Joel

2014-01-01

The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface

Scalable Background-Limited Polarization-Sensitive Detectors for mm-wave Applications

Science.gov (United States)

Rostem, Karwan; Ali, Aamir; Appel, John W.; Bennett, Charles L.; Chuss, David T.; Colazo, Felipe A.; Crowe, Erik; Denis, Kevin L.; Essinger-Hileman, Tom; Marriage, Tobias A.;

Optical Characteristics of a Multichannel Hybrid Integrated Light Source for Ultra-High-Bandwidth Optical Interconnections

Directory of Open Access Journals (Sweden)

Takanori Shimizu

2015-11-01

Full Text Available The optical characteristics of a multi-channel hybrid integrated light source were described for an optical interconnection with a bandwidth of over 10 Tbit/s. The power uniformity of the relative intensity of a 1000-channel light source was shown, and the minimum standard deviation s of the optical power of the 200 output ports at each 25-channel laser diode (LD array was estimated to be 0.49 dB. This hybrid integrated light source is expected to be easily adaptable to a photonics-electronics convergence system for ultra-high-bandwidth interchip interconnections.

Physically Connected Stacked Patch Antenna Design with 100% Bandwidth

KAUST Repository

Klionovski, Kirill; Shamim, Atif

2017-01-01

Typically, stacked patch antennas are parasitically coupled and provide larger bandwidth than a single patch antenna. Here, we show a stacked patch antenna design where square patches with semi-circular cutouts are physically connected to each other. This arrangement provides 100% bandwidth from 23.9–72.2 GHz with consistent high gain (5 dBi or more) across the entire bandwidth. In another variation, a single patch loaded with a superstrate provides 83.5% bandwidth from 25.6–62.3 GHz. The mechanism of bandwidth enhancement is explained through electromagnetic simulations. Measured reflection coefficient, radiation patterns and gain results confirm the extremely wideband performance of the design.

Physically Connected Stacked Patch Antenna Design with 100% Bandwidth

KAUST Repository

Klionovski, Kirill

2017-11-01

Typically, stacked patch antennas are parasitically coupled and provide larger bandwidth than a single patch antenna. Here, we show a stacked patch antenna design where square patches with semi-circular cutouts are physically connected to each other. This arrangement provides 100% bandwidth from 23.9–72.2 GHz with consistent high gain (5 dBi or more) across the entire bandwidth. In another variation, a single patch loaded with a superstrate provides 83.5% bandwidth from 25.6–62.3 GHz. The mechanism of bandwidth enhancement is explained through electromagnetic simulations. Measured reflection coefficient, radiation patterns and gain results confirm the extremely wideband performance of the design.

Properties of CMOS devices and circuits fabricated on high-resistivity, detector-grade silicon

International Nuclear Information System (INIS)

Holland, S.

1991-11-01

A CMOS process that is compatible with silicon p-i-n radiation detectors has been developed and characterized. A total of twelve mask layers are used in the process. The NMOS device is formed in a retrograde well while the PMOS device is fabricated directly in the high-resistivity silicon. Isolation characteristics are similar to a standard foundary CMOS process. Circuit performance using 3 μm design rules has been evaluated. The measured propagation delay and power-delay product for a 51-stage ring oscillator was 1.5 ns and 43 fJ, respectively. Measurements on a simple cascode amplifier results in a gain-bandwidth product of 200 MHz at a bias current of 15 μA. The input-referred noise of the cascode amplifier is 20 nV/√Hz at 1 MHz

Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load

Science.gov (United States)

Dunham, M.E.; Hudson, C.L.

1993-05-11

An improved ultra-high bandwidth helical coil deflection structure for a cathode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.

High precision thermal neutron detectors

Energy Technology Data Exchange (ETDEWEB)

Radeka, V.; Schaknowski, N.A.; Smith, G.C.; Yu, B. [Brookhaven National Laboratory, Upton, NY (United States)

1994-12-31

Two-dimensional position sensitive detectors are indispensable in neutron diffraction experiments for determination of molecular and crystal structures in biology, solid-state physics and polymer chemistry. Some performance characteristics of these detectors are elementary and obvious, such as the position resolution, number of resolution elements, neutron detection efficiency, counting rate and sensitivity to gamma-ray background. High performance detectors are distinguished by more subtle characteristics such as the stability of the response (efficiency) versus position, stability of the recorded neutron positions, dynamic range, blooming or halo effects. While relatively few of them are needed around the world, these high performance devices are sophisticated and fairly complex, their development requires very specialized efforts. In this context, we describe here a program of detector development, based on {sup 3}He filled proportional chambers, which has been underway for some years at the Brookhaven National Laboratory. Fundamental approaches and practical considerations are outlined that have resulted in a series of high performance detectors with the best known position resolution, position stability, uniformity of response and reliability over time, for devices of this type.

Teleoperation over low bandwidth communication links

International Nuclear Information System (INIS)

Fryer, R.J.; Mair, G.M.; Clark, N.; Heng, J.

1996-01-01

Teleoperation is well established for many areas of hazardous environment working. Where such environments are well structured and contained, such as within a working plant, communications bandwidths need not be a constraining factor. However where the worksite is remote, large, poorly structured or damaged communications rapidly become a critical factor in the efficient deployment and use of teleoperation equipment. The paper justifies and describes means which we are exploring to reduce the required communications bandwidth for teleoperation whist retaining full functionality. Techniques involved include incorporation of local intelligence at the worksite, with bandwidth devoted to high-level up-link control signals and down-link feedback, and the use of highly compressed video feeding 'virtual reality type' HMDs to provide maximum system transparency for the operator. The work is drawing on previous experience with an 'anthropomorphic robot heat' for telepresence work, and proprietary algorithms capable of compressing full colour video to standard telephone modem data rates. (Author)

Simple ML Detector for Multiple Antennas Communication System

Directory of Open Access Journals (Sweden)

Ahmad Taqwa

2010-10-01

Full Text Available In order to support providing broadband wireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidth efficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output system using ML (Maximum Likelihood detector to optimize capacity and to increase system performance. What is especially exciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additional frequency-spectral resource. The grand scenario of this concept is the attained advantages of transformation matrices having capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices forms parallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase the system performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacity up to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO.

Development of high frequency and wide bandwidth Johnson noise thermometry

International Nuclear Information System (INIS)

Crossno, Jesse; Liu, Xiaomeng; Kim, Philip; Ohki, Thomas A.; Fong, Kin Chung

2015-01-01

We develop a high frequency, wide bandwidth radiometer operating at room temperature, which augments the traditional technique of Johnson noise thermometry for nanoscale thermal transport studies. Employing low noise amplifiers and an analog multiplier operating at 2 GHz, auto- and cross-correlated Johnson noise measurements are performed in the temperature range of 3 to 300 K, achieving a sensitivity of 5.5 mK (110 ppm) in 1 s of integration time. This setup allows us to measure the thermal conductance of a boron nitride encapsulated monolayer graphene device over a wide temperature range. Our data show a high power law (T ∼ 4) deviation from the Wiedemann-Franz law above T ∼ 100 K

Ionization smoke detectors - the high-voltage issues

International Nuclear Information System (INIS)

Anon.

1992-01-01

Production of high-voltage ionization smoke detectors ceased in 1978 following the development of lower voltage models which used much smaller amounts of radioactive material. Despite this fact, thousands of high-voltage detectors are still in use today in many large UK companies. The major users argue that there is no reason to stop using their detectors if they are still fit for their purpose - many could last for another 15 to 20 years if properly maintained. But pressure has been mounting on businesses to replace all their high-voltage detectors with new low-voltage models within the next couple of years. This could place a huge financial burden on the companies concerned, with costs possibly running into millions of pounds. Traditionally, the major detector installers offered cleaning and maintenance services for high-voltage detectors to their customers but these have now been withdrawn. The installers give no clear reasons for this decision except that the detectors are outmoded and should be disposed of as soon as possible. Most users would agree that conversion to low-voltage types is inevitable but their main worry is the financial strain of replacing all their detectors - and associated equipment - in one go. They would prefer to phase out their high-voltage detectors in stages over a number of years to spread the costs of conversion. The problems of maintenance is discussed. A dual voltage fire alarm panel which allows the high-voltage detectors to be phased out is mentioned. (Author)

Ultra-wide frequency response measurement of an optical system with a DC photo-detector

KAUST Repository

Kuntz, Katanya B.

2017-01-09

Precise knowledge of an optical device\\'s frequency response is crucial for it to be useful in most applications. Traditional methods for determining the frequency response of an optical system (e.g. optical cavity or waveguide modulator) usually rely on calibrated broadband photo-detectors or complicated RF mixdown operations. As the bandwidths of these devices continue to increase, there is a growing need for a characterization method that does not have bandwidth limitations, or require a previously calibrated device. We demonstrate a new calibration technique on an optical system (consisting of an optical cavity and a high-speed waveguide modulator) that is free from limitations imposed by detector bandwidth, and does not require a calibrated photo-detector or modulator. We use a low-frequency (DC) photo-detector to monitor the cavity\\'s optical response as a function of modulation frequency, which is also used to determine the modulator\\'s frequency response. Knowledge of the frequency-dependent modulation depth allows us to more precisely determine the cavity\\'s characteristics (free spectral range and linewidth). The precision and repeatability of our technique is demonstrated by measuring the different resonant frequencies of orthogonal polarization cavity modes caused by the presence of a non-linear crystal. Once the modulator has been characterized using this simple method, the frequency response of any passive optical element can be determined to a fine resolution (e.g. kilohertz) over several gigahertz.

Re-use of Low Bandwidth Equipment for High Bit Rate Transmission Using Signal Slicing Technique

DEFF Research Database (Denmark)

Wagner, Christoph; Spolitis, S.; Vegas Olmos, Juan José

: Massive fiber-to-the-home network deployment requires never ending equipment upgrades operating at higher bandwidth. We show effective signal slicing method, which can reuse low bandwidth opto-electronical components for optical communications at higher bit rates.......: Massive fiber-to-the-home network deployment requires never ending equipment upgrades operating at higher bandwidth. We show effective signal slicing method, which can reuse low bandwidth opto-electronical components for optical communications at higher bit rates....

Photoacoustic projection imaging using an all-optical detector array

Science.gov (United States)

Bauer-Marschallinger, J.; Felbermayer, K.; Berer, T.

2018-02-01

We present a prototype for all-optical photoacoustic projection imaging. By generating projection images, photoacoustic information of large volumes can be retrieved with less effort compared to common photoacoustic computed tomography where many detectors and/or multiple measurements are required. In our approach, an array of 60 integrating line detectors is used to acquire photoacoustic waves. The line detector array consists of fiber-optic MachZehnder interferometers, distributed on a cylindrical surface. From the measured variation of the optical path lengths of the interferometers, induced by photoacoustic waves, a photoacoustic projection image can be reconstructed. The resulting images represent the projection of the three-dimensional spatial light absorbance within the imaged object onto a two-dimensional plane, perpendicular to the line detector array. The fiber-optic detectors achieve a noise-equivalent pressure of 24 Pascal at a 10 MHz bandwidth. We present the operational principle, the structure of the array, and resulting images. The system can acquire high-resolution projection images of large volumes within a short period of time. Imaging large volumes at high frame rates facilitates monitoring of dynamic processes.

Extremelly High Bandwidth Rad Hard Data Acquisition System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Advancements in sensors/detectors are needed to support future NASA mission concepts including polarimetry, large format imaging arrays, and high-sensitivity...

FPGA Compute Acceleration for High-Throughput Data Processing in High-Energy Physics Experiments

CERN Multimedia

CERN. Geneva

2017-01-01

The upgrades of the four large experiments of the LHC at CERN in the coming years will result in a huge increase of data bandwidth for each experiment which needs to be processed very efficiently. For example the LHCb experiment will upgrade its detector 2019/2020 to a 'triggerless' readout scheme, where all of the readout electronics and several sub-detector parts will be replaced. The new readout electronics will be able to readout the detector at 40MHz. This increases the data bandwidth from the detector down to the event filter farm to 40TBit/s, which must be processed to select the interesting proton-proton collisions for later storage. The architecture of such a computing farm, which can process this amount of data as efficiently as possible, is a challenging task and several compute accelerator technologies are being considered.    In the high performance computing sector more and more FPGA compute accelerators are being used to improve the compute performance and reduce the...

High-bandwidth piezoresistive force probes with integrated thermal actuation

International Nuclear Information System (INIS)

Doll, Joseph C; Pruitt, Beth L

2012-01-01

We present high-speed force probes with on-chip actuation and sensing for the measurement of pN-scale forces at the microsecond timescale. We achieve a high resonant frequency in water (1–100 kHz) with requisite low spring constants (0.3–40 pN nm −1 ) and low integrated force noise (1–100 pN) by targeting probe dimensions on the order of 300 nm thick, 1–2 μm wide and 30–200 μm long. Forces are measured using silicon piezoresistors, while the probes are actuated thermally with an aluminum unimorph and silicon heater. The piezoresistive sensors are designed using the open-source numerical optimization code that incorporates constraints on operating temperature. Parylene passivation enables operation in ionic media and we demonstrate simultaneous actuation and sensing. The improved design and fabrication techniques that we describe enable a 10–20-fold improvement in force resolution or measurement bandwidth over prior piezoresistive cantilevers of comparable thickness. (paper)

High bandwidth piezoresistive force probes with integrated thermal actuation

Science.gov (United States)

Doll, Joseph C.; Pruitt, Beth L.

2012-01-01

We present high-speed force probes with on-chip actuation and sensing for the measurement of pN-scale forces at the microsecond time scale. We achieve a high resonant frequency in water (1–100 kHz) with requisite low spring constants (0.3–40 pN/nm) and low integrated force noise (1–100 pN) by targeting probe dimensions on the order of 300 nm thick, 1–2 μm wide and 30–200 μm long. Forces are measured using silicon piezoresistors while the probes are actuated thermally with an aluminum unimorph and silicon heater. The piezoresistive sensors are designed using open source numerical optimization code that incorporates constraints on operating temperature. Parylene passivation enables operation in ionic media and we demonstrate simultaneous actuation and sensing. The improved design and fabrication techniques that we describe enable a 10–20 fold improvement in force resolution or measurement bandwidth over prior piezoresistive cantilevers of comparable thickness. PMID:23175616

Applied techniques for high bandwidth data transfers across wide area networks

International Nuclear Information System (INIS)

Lee, Jason; Gunter, Dan; Tierney, Brian; Allcock, Bill; Bester, Joe; Bresnahan, John; Tuecke, Steve

2001-01-01

Large distributed systems such as Computational/Data Grids require large amounts of data to be co-located with the computing facilities for processing. Ensuring that the data is there in time for the computation in today's Internet is a massive problem. From our work developing a scalable distributed network cache, we have gained experience with techniques necessary to achieve high data throughput over high bandwidth Wide Area Networks (WAN). In this paper, we discuss several hardware and software design techniques and issues, and then describe their application to an implementation of an enhanced FTP protocol called GridFTP. We also describe results from two applications using these techniques, which were obtained at the Supercomputing 2000 conference

Mahanaxar: quality of service guarantees in high-bandwidth, real-time streaming data storage

Energy Technology Data Exchange (ETDEWEB)

Bigelow, David [Los Alamos National Laboratory; Bent, John [Los Alamos National Laboratory; Chen, Hsing-Bung [Los Alamos National Laboratory; Brandt, Scott [UCSC

2010-04-05

Large radio telescopes, cyber-security systems monitoring real-time network traffic, and others have specialized data storage needs: guaranteed capture of an ultra-high-bandwidth data stream, retention of the data long enough to determine what is 'interesting,' retention of interesting data indefinitely, and concurrent read/write access to determine what data is interesting, without interrupting the ongoing capture of incoming data. Mahanaxar addresses this problem. Mahanaxar guarantees streaming real-time data capture at (nearly) the full rate of the raw device, allows concurrent read and write access to the device on a best-effort basis without interrupting the data capture, and retains data as long as possible given the available storage. It has built in mechanisms for reliability and indexing, can scale to meet arbitrary bandwidth requirements, and handles both small and large data elements equally well. Results from our prototype implementation shows that Mahanaxar provides both better guarantees and better performance than traditional file systems.

Large motion high cycle high speed optical fibers for space based applications.

Energy Technology Data Exchange (ETDEWEB)

Stromberg, Peter G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tandon, Rajan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gibson, Cory S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reedlunn, Benjamin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rasberry, Roger David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rohr, Garth David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-10-01

Future remote sensing applications will require higher resolution and therefore higher data rates (up to perhaps 100 gigabits per second) while achieving lower mass and cost. A current limitation to the design space is high speed high bandwidth data does not cross movable gimbals because of cabling issues. This requires the detectors to be off gimbal. The ability to get data across the gimbal would open up efficiencies in designs where the detectors and the electronics can be placed anywhere on the system. Fiber optic cables provide light weight high speed high bandwidth connections. Current options are limited to 20,000 cycles as opposed to the 1,000,000 cycles needed for future space based applications. To extend this to the million+ regime, requires a thorough understanding of the failure mechanisms and the materials, proper selection of materials (e.g., glass and jacket material) allowable geometry changes to the cable, radiation hardness, etc.

A HIGH BANDWIDTH BIPOLAR POWER SUPPLY FOR THE FAST CORRECTORS IN THE APS UPGRADE*

Energy Technology Data Exchange (ETDEWEB)

Wang, Ju; Sprau, Gary

2017-06-25

The APS Upgrade of a multi-bend achromat (MBA) storage ring requires a fast bipolar power supply for the fast correction magnets. The key performance requirement of the power supply includes a small-signal bandwidth of 10 kHz for the output current. This requirement presents a challenge to the design because of the high inductance of the magnet load and a limited input DC voltage. A prototype DC/DC power supply utilizing a MOSFET H-bridge circuit with a 500 kHz PWM has been developed and tested successfully. The prototype achieved a 10-kHz bandwidth with less than 3-dB attenuation for a signal 0.5% of the maximum operating current of 15 amperes. This paper presents the design of the power circuit, the PWM method, the control loop, and the test results.

High performance visual display for HENP detectors

International Nuclear Information System (INIS)

McGuigan, Michael; Smith, Gordon; Spiletic, John; Fine, Valeri; Nevski, Pavel

2001-01-01

A high end visual display for High Energy Nuclear Physics (HENP) detectors is necessary because of the sheer size and complexity of the detector. For BNL this display will be of special interest because of STAR and ATLAS. To load, rotate, query, and debug simulation code with a modern detector simply takes too long even on a powerful work station. To visualize the HENP detectors with maximal performance we have developed software with the following characteristics. We develop a visual display of HENP detectors on BNL multiprocessor visualization server at multiple level of detail. We work with general and generic detector framework consistent with ROOT, GAUDI etc, to avoid conflicting with the many graphic development groups associated with specific detectors like STAR and ATLAS. We develop advanced OpenGL features such as transparency and polarized stereoscopy. We enable collaborative viewing of detector and events by directly running the analysis in BNL stereoscopic theatre. We construct enhanced interactive control, including the ability to slice, search and mark areas of the detector. We incorporate the ability to make a high quality still image of a view of the detector and the ability to generate animations and a fly through of the detector and output these to MPEG or VRML models. We develop data compression hardware and software so that remote interactive visualization will be possible among dispersed collaborators. We obtain real time visual display for events accumulated during simulations

Scanning fluorescence detector for high-throughput DNA genotyping

Science.gov (United States)

Rusch, Terry L.; Petsinger, Jeremy; Christensen, Carl; Vaske, David A.; Brumley, Robert L., Jr.; Luckey, John A.; Weber, James L.

1996-04-01

A new scanning fluorescence detector (SCAFUD) was developed for high-throughput genotyping of short tandem repeat polymorphisms (STRPs). Fluorescent dyes are incorporated into relatively short DNA fragments via polymerase chain reaction (PCR) and are separated by electrophoresis in short, wide polyacrylamide gels (144 lanes with well to read distances of 14 cm). Excitation light from an argon laser with primary lines at 488 and 514 nm is introduced into the gel through a fiber optic cable, dichroic mirror, and 40X microscope objective. Emitted fluorescent light is collected confocally through a second fiber. The confocal head is translated across the bottom of the gel at 0.5 Hz. The detection unit utilizes dichroic mirrors and band pass filters to direct light with 10 - 20 nm bandwidths to four photomultiplier tubes (PMTs). PMT signals are independently amplified with variable gain and then sampled at a rate of 2500 points per scan using a computer based A/D board. LabView software (National Instruments) is used for instrument operation. Currently, three fluorescent dyes (Fam, Hex and Rox) are simultaneously detected with peak detection wavelengths of 543, 567, and 613 nm, respectively. The detection limit for fluorescein-labeled primers is about 100 attomoles. Planned SCAFUD upgrades include rearrangement of laser head geometry, use of additional excitation lasers for simultaneous detection of more dyes, and the use of detector arrays instead of individual PMTs. Extensive software has been written for automatic analysis of SCAFUD images. The software enables background subtraction, band identification, multiple- dye signal resolution, lane finding, band sizing and allele calling. Whole genome screens are currently underway to search for loci influencing such complex diseases as diabetes, asthma, and hypertension. Seven production SCAFUDs are currently in operation. Genotyping output for the coming year is projected to be about one million total genotypes (DNA

Towards Bandwidth Scalable Transceiver Technology for Optical Metro-Access Networks

DEFF Research Database (Denmark)

Spolitis, Sandis; Bobrovs, Vjaceslavs; Wagner, Christoph

2015-01-01

sliceable transceiver for 1 Gbit/s non-return to zero (NRZ) signal sliced into two slices is presented. Digital signal processing (DSP) power consumption and latency values for proposed sliceable transceiver technique are also discussed. In this research post FEC with 7% overhead error free transmission has......Massive fiber-to-the-home network deployment is creating a challenge for telecommunications network operators: exponential increase of the power consumption at the central offices and a never ending quest for equipment upgrades operating at higher bandwidth. In this paper, we report on flexible...... signal slicing technique, which allows transmission of high-bandwidth signals via low bandwidth electrical and optoelectrical equipment. The presented signal slicing technique is highly scalable in terms of bandwidth which is determined by the number of slices used. In this paper performance of scalable...

The status of the Brazilian spherical detector

International Nuclear Information System (INIS)

Aguiar, O D; Andrade, L A; Filho, L Camargo; Costa, C A; Araujo, J C N de; Neto, E C de Rey; Souza, S T de; Fauth, A C; Frajuca, C; Frossati, G; Furtado, S R; Furtado, V G S; Magalhaes, N S; Jr, R M Marinho; Matos, E S; Meliani, M T; Melo, J L; Miranda, O D; Jr, N F Oliveira; Ribeiro, K L; Salles, K B M; Stellati, C; Jr, W F Velloso

2002-01-01

The first phase of the Brazilian Graviton Project is the construction and operation of the gravitational wave detector Mario Schenberg at the Physics Institute of the University of Sao Paulo. This gravitational wave spherical antenna is planned to feature a sensitivity better than h = 10 -21 Hz -1/2 at the 3.0-3.4 kHz bandwidth, and to work not only as a detector, but also as a testbed for the development of new technologies. Here we present the status of this detector

ICE-Based Custom Full-Mesh Network for the CHIME High Bandwidth Radio Astronomy Correlator

Science.gov (United States)

Bandura, K.; Cliche, J. F.; Dobbs, M. A.; Gilbert, A. J.; Ittah, D.; Mena Parra, J.; Smecher, G.

2016-03-01

New generation radio interferometers encode signals from thousands of antenna feeds across large bandwidth. Channelizing and correlating this data requires networking capabilities that can handle unprecedented data rates with reasonable cost. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) correlator processes 8-bits from N=2,048 digitizer inputs across 400MHz of bandwidth. Measured in N2× bandwidth, it is the largest radio correlator that is currently commissioning. Its digital back-end must exchange and reorganize the 6.6terabit/s produced by its 128 digitizing and channelizing nodes, and feed it to the 256 graphics processing unit (GPU) node spatial correlator in a way that each node obtains data from all digitizer inputs but across a small fraction of the bandwidth (i.e. ‘corner-turn’). In order to maximize performance and reliability of the corner-turn system while minimizing cost, a custom networking solution has been implemented. The system makes use of Field Programmable Gate Array (FPGA) transceivers to implement direct, passive copper, full-mesh, high speed serial connections between sixteen circuit boards in a crate, to exchange data between crates, and to offload the data to a cluster of 256 GPU nodes using standard 10Gbit/s Ethernet links. The GPU nodes complete the corner-turn by combining data from all crates and then computing visibilities. Eye diagrams and frame error counters confirm error-free operation of the corner-turn network in both the currently operating CHIME Pathfinder telescope (a prototype for the full CHIME telescope) and a representative fraction of the full CHIME hardware providing an end-to-end system validation. An analysis of an equivalent corner-turn system built with Ethernet switches instead of custom passive data links is provided.

High performance visual display for HENP detectors

CERN Document Server

McGuigan, M; Spiletic, J; Fine, V; Nevski, P

2001-01-01

A high end visual display for High Energy Nuclear Physics (HENP) detectors is necessary because of the sheer size and complexity of the detector. For BNL this display will be of special interest because of STAR and ATLAS. To load, rotate, query, and debug simulation code with a modern detector simply takes too long even on a powerful work station. To visualize the HENP detectors with maximal performance we have developed software with the following characteristics. We develop a visual display of HENP detectors on BNL multiprocessor visualization server at multiple level of detail. We work with general and generic detector framework consistent with ROOT, GAUDI etc, to avoid conflicting with the many graphic development groups associated with specific detectors like STAR and ATLAS. We develop advanced OpenGL features such as transparency and polarized stereoscopy. We enable collaborative viewing of detector and events by directly running the analysis in BNL stereoscopic theatre. We construct enhanced interactiv...

High tracking resolution detectors. Final Technical Report

International Nuclear Information System (INIS)

Vasile, Stefan; Li, Zheng

2010-01-01

High-resolution tracking detectors based on Active Pixel Sensor (APS) have been valuable tools in Nuclear Physics and High-Energy Physics research, and have contributed to major discoveries. Their integration time, radiation length and readout rate is a limiting factor for the planed luminosity upgrades in nuclear and high-energy physics collider-based experiments. The goal of this program was to demonstrate and develop high-gain, high-resolution tracking detector arrays with faster readout, and shorter radiation length than APS arrays. These arrays may operate as direct charged particle detectors or as readouts of high resolution scintillating fiber arrays. During this program, we developed in CMOS large, high-resolution pixel sensor arrays with integrated readout, and reset at pixel level. Their intrinsic gain, high immunity to surface and moisture damage, will allow operating these detectors with minimal packaging/passivation requirements and will result in radiation length superior to APS. In Phase I, we designed and fabricated arrays with calorimetric output capable of sub-pixel resolution and sub-microsecond readout rate. The technical effort was dedicated to detector and readout structure development, performance verification, as well as to radiation damage and damage annealing.

Theoretical investigation of injection-locked high modulation bandwidth quantum cascade lasers.

Science.gov (United States)

Meng, Bo; Wang, Qi Jie

2012-01-16

In this study, we report for the first time to our knowledge theoretical investigation of modulation responses of injection-locked mid-infrared quantum cascade lasers (QCLs) at wavelengths of 4.6 μm and 9 μm, respectively. It is shown through a three-level rate equations model that the direct intensity modulation of QCLs gives the maximum modulation bandwidths of ~7 GHz at 4.6 μm and ~20 GHz at 9 μm. By applying the injection locking scheme, we find that the modulation bandwidths of up to ~30 GHz and ~70 GHz can be achieved for QCLs at 4.6 μm and 9 μm, respectively, with an injection ratio of 5 dB. The result also shows that an ultrawide modulation bandwidth of more than 200 GHz is possible with a 10 dB injection ratio for QCLs at 9 μm. An important characteristic of injection-locked QCLs is the nonexistence of unstable locking region in the locking map, in contrast to their diode laser counterparts. We attribute this to the ultra-short upper laser state lifetimes of QCLs.

High Bandwidth Communications Links Between Heterogeneous Autonomous Vehicles Using Sensor Network Modeling and Extremum Control Approaches

Science.gov (United States)

2008-12-01

In future network-centric warfare environments, teams of autonomous vehicles will be deployed in a coorperative manner to conduct wide-area...of data back to the command station, autonomous vehicles configured with high bandwidth communication system are positioned between the command

EMG-Torque Dynamics Change With Contraction Bandwidth.

Science.gov (United States)

Golkar, Mahsa A; Jalaleddini, Kian; Kearney, Robert E

2018-04-01

An accurate model for ElectroMyoGram (EMG)-torque dynamics has many uses. One of its applications which has gained high attention among researchers is its use, in estimating the muscle contraction level for the efficient control of prosthesis. In this paper, the dynamic relationship between the surface EMG and torque during isometric contractions at the human ankle was studied using system identification techniques. Subjects voluntarily modulated their ankle torque in dorsiflexion direction, by activating their tibialis anterior muscle, while tracking a pseudo-random binary sequence in a torque matching task. The effects of contraction bandwidth, described by torque spectrum, on EMG-torque dynamics were evaluated by varying the visual command switching time. Nonparametric impulse response functions (IRF) were estimated between the processed surface EMG and torque. It was demonstrated that: 1) at low contraction bandwidths, the identified IRFs had unphysiological anticipatory (i.e., non-causal) components, whose amplitude decreased as the contraction bandwidth increased. We hypothesized that this non-causal behavior arose, because the EMG input contained a component due to feedback from the output torque, i.e., it was recorded from within a closed-loop. Vision was not the feedback source since the non-causal behavior persisted when visual feedback was removed. Repeating the identification using a nonparametric closed-loop identification algorithm yielded causal IRFs at all bandwidths, supporting this hypothesis. 2) EMG-torque dynamics became faster and the bandwidth of system increased as contraction modulation rate increased. Thus, accurate prediction of torque from EMG signals must take into account the contraction bandwidth sensitivity of this system.

Linearity of photoconductive GaAs detectors to pulsed electrons

International Nuclear Information System (INIS)

Ziegler, L.H.

1995-01-01

The response of neutron damaged GaAs photoconductor detectors to intense, fast (50 psec fwhm) pulses of 16 MeV electrons has been measured. Detectors made from neutron damaged GaAs are known to have reduced gain, but significantly improved bandwidth. An empirical relationship between the observed signal and the incident electron fluence has been determined

Requirements on high resolution detectors

Energy Technology Data Exchange (ETDEWEB)

Koch, A. [European Synchrotron Radiation Facility, Grenoble (France)

1997-02-01

For a number of microtomography applications X-ray detectors with a spatial resolution of 1 {mu}m are required. This high spatial resolution will influence and degrade other parameters of secondary importance like detective quantum efficiency (DQE), dynamic range, linearity and frame rate. This note summarizes the most important arguments, for and against those detector systems which could be considered. This article discusses the mutual dependencies between the various figures which characterize a detector, and tries to give some ideas on how to proceed in order to improve present technology.

Effect of Feed Substrate Thickness on the Bandwidth and Radiation Characteristics of an Aperture-Coupled Microstrip Antenna with a High Permittivity Feed Substrate

Directory of Open Access Journals (Sweden)

Jae-Hyun Kim

2018-04-01

Full Text Available The impedance bandwidth and radiation characteristics of an aperture-coupled microstrip line-fed patch antenna (ACMPA with a high permittivity (ɛr = 10 feed substrate suitable for integration with a monolithic microwave integrated circuit (MMIC are investigated for various feed substrate thicknesses through an experiment and computer simulation. The impedance bandwidth of an ACMPA with a high permittivity feed substrate increases as the feed substrate thickness decreases. Furthermore, the front-to-back ratio of an ACMPA with a high permittivity feed substrate increases and the cross-polarization level decreases as the feed substrate thickness decreases. As the impedance bandwidth of an ACMPA with a high permittivity feed substrate increases and its radiation characteristics improve as the feed substrate thickness decreases, the ACMPA configuration becomes suitable for integration with an MMIC.

Sensitivity-Bandwidth Limit in a Multimode Optoelectromechanical Transducer

Science.gov (United States)

Moaddel Haghighi, I.; Malossi, N.; Natali, R.; Di Giuseppe, G.; Vitali, D.

2018-03-01

An optoelectromechanical system formed by a nanomembrane capacitively coupled to an L C resonator and to an optical interferometer has recently been employed for the highly sensitive optical readout of rf signals [T. Bagci et al., Nature (London) 507, 81 (2013), 10.1038/nature13029]. We propose and experimentally demonstrate how the bandwidth of such a transducer can be increased by controlling the interference between two electromechanical interaction pathways of a two-mode mechanical system. With a proof-of-principle device operating at room temperature, we achieve a sensitivity of 300 nV /√{Hz } over a bandwidth of 15 kHz in the presence of radio-frequency noise, and an optimal shot-noise-limited sensitivity of 10 nV /√{Hz } over a bandwidth of 5 kHz. We discuss strategies for improving the performance of the device, showing that, for the same given sensitivity, a mechanical multimode transducer can achieve a bandwidth significantly larger than that for a single-mode one.

Data analysis-based autonomic bandwidth adjustment in software defined multi-vendor optical transport networks.

Science.gov (United States)

Li, Yajie; Zhao, Yongli; Zhang, Jie; Yu, Xiaosong; Jing, Ruiquan

2017-11-27

Network operators generally provide dedicated lightpaths for customers to meet the demand for high-quality transmission. Considering the variation of traffic load, customers usually rent peak bandwidth that exceeds the practical average traffic requirement. In this case, bandwidth provisioning is unmetered and customers have to pay according to peak bandwidth. Supposing that network operators could keep track of traffic load and allocate bandwidth dynamically, bandwidth can be provided as a metered service and customers would pay for the bandwidth that they actually use. To achieve cost-effective bandwidth provisioning, this paper proposes an autonomic bandwidth adjustment scheme based on data analysis of traffic load. The scheme is implemented in a software defined networking (SDN) controller and is demonstrated in the field trial of multi-vendor optical transport networks. The field trial shows that the proposed scheme can track traffic load and realize autonomic bandwidth adjustment. In addition, a simulation experiment is conducted to evaluate the performance of the proposed scheme. We also investigate the impact of different parameters on autonomic bandwidth adjustment. Simulation results show that the step size and adjustment period have significant influences on bandwidth savings and packet loss. A small value of step size and adjustment period can bring more benefits by tracking traffic variation with high accuracy. For network operators, the scheme can serve as technical support of realizing bandwidth as metered service in the future.

Wideband and high-gain frequency stabilization of a 100-W injection-locked Nd:YAG laser for second-generation gravitational wave detectors.

Science.gov (United States)

Ohmae, Noriaki; Moriwaki, Shigenori; Mio, Norikatsu

2010-07-01

Second-generation gravitational wave detectors require a highly stable laser with an output power greater than 100 W to attain their target sensitivity. We have developed a frequency stabilization system for a 100-W injection-locked Nd:YAG (yttrium aluminum garnet) laser. By placing an external wideband electro-optic modulator used as a fast-frequency actuator in the optical path of the slave output, we can circumvent a phase delay in the frequency control loop originating from the pole of an injection-locked slave cavity. Thus, we have developed an electro-optic modulator made of a MgO-doped stoichiometric LiNbO(3) crystal. Using this modulator, we achieve a frequency control bandwidth of 800 kHz and a control gain of 180 dB at 1 kHz. These values satisfy the requirement for a laser frequency control loop in second-generation gravitational wave detectors.

CALDER: High-sensitivity cryogenic light detectors

International Nuclear Information System (INIS)

Casali, N.; Bellini, F.; Cardani, L.

2017-01-01

The current bolometric experiments searching for rare processes such as neutrinoless double-beta decay or dark matter interaction demand for cryogenic light detectors with high sensitivity, large active area and excellent scalability and radio-purity in order to reduce their background budget. The CALDER project aims to develop such kind of light detectors implementing phonon-mediated Kinetic Inductance Detectors (KIDs). The goal for this project is the realization of a 5 × 5 cm"2 light detector working between 10 and 100mK with a baseline resolution RMS below 20 eV. In this work the characteristics and the performances of the prototype detectors developed in the first project phase will be shown.

Bandwidth Limitations in Characterization of High Intensity Focused Ultrasound Fields in the Presence of Shocks

Science.gov (United States)

Khokhlova, V. A.; Bessonova, O. V.; Soneson, J. E.; Canney, M. S.; Bailey, M. R.; Crum, L. A.

2010-03-01

Nonlinear propagation effects result in the formation of weak shocks in high intensity focused ultrasound (HIFU) fields. When shocks are present, the wave spectrum consists of hundreds of harmonics. In practice, shock waves are modeled using a finite number of harmonics and measured with hydrophones that have limited bandwidths. The goal of this work was to determine how many harmonics are necessary to model or measure peak pressures, intensity, and heat deposition rates of the HIFU fields. Numerical solutions of the Khokhlov-Zabolotskaya-Kuznetzov-type (KZK) nonlinear parabolic equation were obtained using two independent algorithms, compared, and analyzed for nonlinear propagation in water, in gel phantom, and in tissue. Measurements were performed in the focus of the HIFU field in the same media using fiber optic probe hydrophones of various bandwidths. Experimental data were compared to the simulation results.

Semiconductor high-energy radiation scintillation detector

International Nuclear Information System (INIS)

Kastalsky, A.; Luryi, S.; Spivak, B.

2006-01-01

We propose a new scintillation-type detector in which high-energy radiation generates electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. An important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombination time of minority carriers. Notably, the fast response comes without any degradation in brightness. When the scintillator is implemented in a qualified semiconductor material (such as InP or GaAs), the photo-detector and associated circuits can be epitaxially integrated on the scintillator slab and the structure can be stacked-up to achieve virtually any desired absorption capability

Strip detector for the ATLAS detector upgrade for the High-Luminosity LHC

CERN Document Server

Veloce, Laurelle Maria; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High Luminosity LHC, scheduled for 2025. The expected radiation damage at an integrated luminosity of 3000fb-1 will require the tracking detectors to withstand hadron fluencies to over 1x1016 1 MeV neutron equivalent per cm2. With the addition of increased readout rates, the existing Inner Detector will have to be replaced by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The ITk strip detector consists of a four-layer barrel and a forward region composed of six discs on each side of the barrel. The current prototyping phase has resulted in the ITk Strip Detector Technical Design Report (TDR), which starts the pre-production readiness phase at the involved institutes. In this contribution we present the design of the ITk Strip Detector and current status of R&D of various detector components.

Multi-granularity Bandwidth Allocation for Large-Scale WDM/TDM PON

Science.gov (United States)

Gao, Ziyue; Gan, Chaoqin; Ni, Cuiping; Shi, Qiongling

2017-12-01

WDM (wavelength-division multiplexing)/TDM (time-division multiplexing) PON (passive optical network) is being viewed as a promising solution for delivering multiple services and applications, such as high-definition video, video conference and data traffic. Considering the real-time transmission, QoS (quality of services) requirements and differentiated services model, a multi-granularity dynamic bandwidth allocation (DBA) in both domains of wavelengths and time for large-scale hybrid WDM/TDM PON is proposed in this paper. The proposed scheme achieves load balance by using the bandwidth prediction. Based on the bandwidth prediction, the wavelength assignment can be realized fairly and effectively to satisfy the different demands of various classes. Specially, the allocation of residual bandwidth further augments the DBA and makes full use of bandwidth resources in the network. To further improve the network performance, two schemes named extending the cycle of one free wavelength (ECoFW) and large bandwidth shrinkage (LBS) are proposed, which can prevent transmission from interruption when the user employs more than one wavelength. The simulation results show the effectiveness of the proposed scheme.

The Gravitational Wave Detector EXPLORER

CERN Multimedia

2002-01-01

%RE5 EXPLORER is a cryogenic resonant-mass gravitational wave (GW) detector. It is in operation at CERN since 1984 and it has been the first cryogenic GW antenna to perform continuous observations (since 1990).\\\\ \\\\EXPLORER is actually part of the international network of resonant-mass detectors which includes ALLEGRO at the Louisiana State University, AURIGA at the INFN Legnaro Laboratories, NAUTILUS at the INFN Frascati Laboratories and NIOBE at the University of Western Australia. The EXPLORER sensitivity, at present of the same order of the other antennas, is 10$^{-20}$ Hz$^{-1/2}$ over a bandwidth of 20 Hz and 6 10$^{-22}$ Hz$^{-1/2}$ with a bandwidth of about 0.5 Hz, corresponding to a sensitivity to short GW bursts of \\textit{h} = 6 10$^{-19}$.\\\\ \\\\This sensitivity should allow the detection of the burst sources in our Galaxy and in the Local Group. No evidence of GW signals has been reported up to now.\\\\ \\\\The principle of operation is based on the assumption that any vibrational mode of a resonant bo...

On Bandwidth Efficient Modulation for High-Data-Rate Wireless LAN Systems

Directory of Open Access Journals (Sweden)

Stolpman Victor

2002-01-01

Full Text Available We address the problem of high-data-rate orthogonal frequency division multiplexed (OFDM systems under restrictive bandwidth constraints. Based on recent theoretic results, multiple-input multiple-output (MIMO configurations are best suited for this problem. In this paper, we examine several MIMO configurations suitable for high rate transmission. In all scenarios considered, perfect channel state information (CSI is assumed at the receiver. In constrast, availability of CSI at the transmitter is addressed separately. We show that powerful space-time codes can be developed by combining some simple well-known techniques. In fact, we show that for certain configurations, these space-time MIMO configurations are near optimum in terms of outage capacity as compared to previously published codes. Performance evaluation of these techniques is demonstrated within the IEEE 802.11a framework via Monte Carlo simulations.

Proceedings of the symposium on high energy detectors

International Nuclear Information System (INIS)

1980-02-01

Since the study meeting on measuring instruments held three years ago, large change has arisen. Valuable experiences have been accumulated by the successful conclusion of the first term experiments in the National Laboratory for High Energy Physics. The improvement of detectors and the development of new detectors are strongly desired just before starting the future plans. In low energy field also, the steady advance has been accomplished. This symposium was held in such situation on September 18 and 19, 1979, at KEK, and aimed at clarifying the present status and accomplishment of high energy detectors, and setting forth the future prospect. On the first day, the review of recent topics concerning position detectors and particle-identifying detectors, and the reports on drift chambers, liquid wire chambers and the single wire chambers using charge division method were mainly presented. On the second day, the reports on the electronics related to position detectors, particle-identifying detectors, calorimeters, and the development of new detectors, the consideration on multiple tracks as the future plan, and the review of transition radiation detectors were presented. The results of this symposium will surely be utilized for the high energy experiments hereafter. The 26 papers presented are outlined. (Kako, I.)

Epitaxial silicon semiconductor detectors, past developments, future prospects

International Nuclear Information System (INIS)

Gruhn, C.R.

1976-01-01

A review of the main physical characteristics of epitaxial silicon as it relates to detector development is presented. As examples of applications results are presented on (1) epitaxial silicon avalanche diodes (ESAD); signal-to-noise, non-linear aspects of the avalanche gain mechanism, gain-bandwidth product, (2) ultrathin epitaxial silicon surface barrier (ESSB) detectors, response to heavy ions, (3) an all-epitaxial silicon diode (ESD), response to heavy ions, charge transport and charge defect. Future prospects of epitaxial silicon as it relates to new detector designs are summarized

Photomask specifications for high energy physics detectors

CERN Document Server

Pindo, M

2002-01-01

Planar technologies used for radiation detector fabrication imply an extensive use of photomasks whose characteristics are critical in determining final detector performance. Compatibly with their manufacturing process, photomasks must satisfy the application-specific requirements dictated both by wafer manufacturers and detector final users. The design and realization of microstrip and pixel detectors, widely used in high energy physics experiments, ask for intensive scientific effort, advanced technology and important economical investments. Photomask specification definition is one of the fundamental steps to optimize detector fabrication processes and fulfill experimental requirements at the most appropriate cost.

Pyroelectric detectors with integrated operational amplifier for high modulation frequencies; Pyroelektrische Detektoren mit integriertem Operationsverstaerker fuer hohe Modulationsfrequenzen

Energy Technology Data Exchange (ETDEWEB)

Neumann, N.; Saenze, H.; Heinze, M. [InfraTec GmbH Dresden (Germany)

2006-02-01

In order to use the advantages of the current mode operation a pyroelectric detector family with integrated transimpedance amplifier (TIA) was developed particularly for modulation frequencies up to the kHz range with a simplified external circuitry for new application fields, e.g. absorption spectroscopy using quantum-cascade-laser. The essential advantages of the TIA arise from the small electrical time constant {tau}{sub E} and the short-circuiting of the pyroelectric element. A flat amplitude response up to some kHz was aimed at for a sufficiently high response of 7500 V/W, appr., also at high modulation frequencies. This can be achieved through a electrical time constant of 1 ms or less and a wide bandwidth of the op amp. The article describes in detail how these demands were accomplished and which compromises had to be accepted. (orig.)

Efficient Bandwidth Management for Ethernet Passive Optical Networks

KAUST Repository

Elrasad, Amr Elsayed M.

2016-05-15

The increasing bandwidth demands in access networks motivates network operators, networking devices manufacturers, and standardization institutions to search for new approaches for access networks. These approaches should support higher bandwidth, longer distance between end user and network operator, and less energy consumption. Ethernet Passive Optical Network (EPON) is a favorable choice for broadband access networks. EPONs support transmission rates up to 10 Gbps. EPONs also support distance between end users and central office up to 20 Km. Moreover, optical networks have the least energy consumption among all types of networks. In this dissertation, we focus on reducing delay and saving energy in EPONs. Reducing delay is essential for delay-sensitive traffic, while minimizing energy consumption is an environmental necessity and also reduces the network operating costs. We identify five challenges, namely excess bandwidth allocation, frame delineation, congestion resolution, large round trip time delay in long-reach EPONs (LR-EPONs), and energy saving. We provide a Dynamic Bandwidth Allocation (DBA) approach for each challenge. We also propose a novel scheme that combines the features of the proposed approaches in one highly performing scheme. Our approach is to design novel DBA protocols that can further reduce the delay and be simultaneously simple and fair. We also present a dynamic bandwidth allocation scheme for Green EPONs taking into consideration maximizing energy saving under target delay constraints. Regarding excess bandwidth allocation, we develop an effective DBA scheme called Delayed Excess Scheduling (DES). DES achieves significant delay and jitter reduction and is more suitable for industrial deployment due to its simplicity. Utilizing DES in hybrid TDM/WDM EPONs (TWDM-EPONs) is also investigated. We also study eliminating the wasted bandwidth due to frame delineation. We develop an interactive DBA scheme, Efficient Grant Sizing Interleaved

A Track Reconstructing Low-latency Trigger Processor for High-energy Physics

CERN Document Server

AUTHOR|(CDS)2067518

2009-01-01

The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 µs to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbps via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's dr...

Design of bandwidth tunable HTS filter using H-shaped waveguides

Energy Technology Data Exchange (ETDEWEB)

Koike, Y. [Department of Electrical Engineering, University of Yamanashi, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Sekiya, N., E-mail: nsekiya@yamanashi.ac.j [Department of Electrical Engineering, University of Yamanashi, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Nakagawa, Y. [Department of Electrical Engineering, University of Yamanashi, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ohshima, S. [Yamagata University, 4-3-16 Johnan, Yonezawa 992-8510 (Japan)

2009-10-15

We have developed a bandwidth tuning method for use in high-temperature superconducting (HTS) microstrip filters. Several H-shaped waveguides are placed between the resonators, and the bandwidth is adjusted by changing the switch states of the waveguides. The coupling coefficients between the resonators are controlled by switching the connection or isolation of the center gaps of the waveguides so as to tune the bandwidth. The effects of using this method were evaluated by simulation using a filter composed of 3-pole half-wavelength straight-line resonators with an H-shaped waveguide between each pair and additional electric pads for post-tuning trimming. The filter was designed to have a center frequency of 5 GHz and a bandwidth of 100 MHz by using an electromagnetic simulator based on the moment method. The simulation showed that bandwidth tuning of 150 MHz can be obtained by using H-shaped waveguides to adjust the coupling coefficients. It also showed that using additional electric pads around the feed lines, which was previously shown to be useful for trimming to improve insertion loss after center-frequency tuning, is also useful for bandwidth tuning.

In-circuit-measurement of parasitic elements in high gain high bandwidth low noise transimpedance amplifiers.

Science.gov (United States)

Cochems, P; Kirk, A; Zimmermann, S

2014-12-01

Parasitic elements play an important role in the development of every high performance circuit. In the case of high gain, high bandwidth transimpedance amplifiers, the most important parasitic elements are parasitic capacitances at the input and in the feedback path, which significantly influence the stability, the frequency response, and the noise of the amplifier. As these parasitic capacitances range from a few picofarads down to only a few femtofarads, it is nearly impossible to measure them accurately using traditional LCR meters. Unfortunately, they also cannot be easily determined from the transfer function of the transimpedance amplifier, as it contains several overlapping effects and its measurement is only possible when the circuit is already stable. Therefore, we developed an in-circuit measurement method utilizing minimal modifications to the input stage in order to measure its parasitic capacitances directly and with unconditional stability. Furthermore, using the data acquired with this measurement technique, we both proposed a model for the complicated frequency response of high value thick film resistors as they are used in high gain transimpedance amplifiers and optimized our transimpedance amplifier design.

Research of high energy radioactivity identification detector

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Kyun; Lee, Yong Bum; Hwang, Jong Sun; Choi, Seok Ki

1998-07-01

{Delta} {Epsilon}-{Epsilon} telescope high radioactivity detector was designed, fabricated, and tested at the 35 MeV proton energy. We developed the computer code to calculate the energy loss of projectile ions in the matter. Using the code, we designed and fabricated a detector to measure 15-50 MeV protons. The detector was successfully tested to measure the energy of protons and deuterons and to identify the ions. In future, we would like to extend the present result to the development of a higher energy proton detector and a heavy ion detector. (author). 10 refs., 3 tabs., 14 figs

Improved-Bandwidth Transimpedance Amplifier

Science.gov (United States)

Chapsky, Jacob

2009-01-01

The widest available operational amplifier, with the best voltage and current noise characteristics, is considered for transimpedance amplifier (TIA) applications where wide bandwidth is required to handle fast rising input signals (as for time-of-flight measurement cases). The added amplifier inside the TIA feedback loop can be configured to have slightly lower voltage gain than the bandwidth reduction factor.

Wide-bandwidth bilateral control using two-stage actuator system

International Nuclear Information System (INIS)

Kokuryu, Saori; Izutsu, Masaki; Kamamichi, Norihiro; Ishikawa, Jun

2015-01-01

This paper proposes a two-stage actuator system that consists of a coarse actuator driven by a ball screw with an AC motor (the first stage) and a fine actuator driven by a voice coil motor (the second stage). The proposed two-stage actuator system is applied to make a wide-bandwidth bilateral control system without needing expensive high-performance actuators. In the proposed system, the first stage has a wide moving range with a narrow control bandwidth, and the second stage has a narrow moving range with a wide control bandwidth. By consolidating these two inexpensive actuators with different control bandwidths in a complementary manner, a wide bandwidth bilateral control system can be constructed based on a mechanical impedance control. To show the validity of the proposed method, a prototype of the two-stage actuator system has been developed and basic performance was evaluated by experiment. The experimental results showed that a light mechanical impedance with a mass of 10 g and a damping coefficient of 2.5 N/(m/s) that is an important factor to establish good transparency in bilateral control has been successfully achieved and also showed that a better force and position responses between a master and slave is achieved by using the proposed two-stage actuator system compared with a narrow bandwidth case using a single ball screw system. (author)

The influence of anisotropic electron drift velocity on the signal shapes of closed-end HPGe detectors

CERN Document Server

Mihailescu, L; Lieder, R M; Brands, H; Jaeger, H

2000-01-01

This study is concerned with the anisotropy of the electron drift velocity in germanium crystals at high electric fields and low temperature, and its influence on the charge collection process in n-type, high-purity germanium (HPGe) detectors of closed-end, coaxial geometry. The electron trajectories inside HPGe detectors are simulated using a phenomenological model to calculate the dependence of the drift velocity on the angle between the electric field and the crystal orientation. The resulting induced currents and pulse shapes for a given detector geometry and preamplifier bandwidth are compared to experiment. Experimentally, the dependence of the pulse shapes on the conductivity anisotropy in closed-end HPGe detectors was observed. The experimental data on pulse shapes were obtained by sampling preamplifier signals of an encapsulated, hexaconical EUROBALL detector, which was irradiated by collimated sup 2 sup 2 Na and sup 2 sup 4 sup 1 Am sources. The crystal orientation was measured by neutron reflection...

APEnet+: high bandwidth 3D torus direct network for petaflops scale commodity clusters

International Nuclear Information System (INIS)

Ammendola, R; Salamon, A; Salina, G; Biagioni, A; Prezza, O; Cicero, F Lo; Lonardo, A; Paolucci, P S; Rossetti, D; Tosoratto, L; Vicini, P; Simula, F

2011-01-01

We describe herein the APElink+ board, a PCIe interconnect adapter featuring the latest advances in wire speed and interface technology plus hardware support for a RDMA programming model and experimental acceleration of GPU networking; this design allows us to build a low latency, high bandwidth PC cluster, the APEnet+ network, the new generation of our cost-effective, tens-of-thousands-scalable cluster network architecture. Some test results and characterization of data transmission of a complete testbench, based on a commercial development card mounting an Altera ® FPGA, are provided.

APEnet+: high bandwidth 3D torus direct network for petaflops scale commodity clusters

Energy Technology Data Exchange (ETDEWEB)

Ammendola, R; Salamon, A; Salina, G [INFN Tor Vergata, Roma (Italy); Biagioni, A; Prezza, O; Cicero, F Lo; Lonardo, A; Paolucci, P S; Rossetti, D; Tosoratto, L; Vicini, P [INFN Roma, Roma (Italy); Simula, F [Sapienza Universita di Roma, Roma (Italy)

2011-12-23

We describe herein the APElink+ board, a PCIe interconnect adapter featuring the latest advances in wire speed and interface technology plus hardware support for a RDMA programming model and experimental acceleration of GPU networking; this design allows us to build a low latency, high bandwidth PC cluster, the APEnet+ network, the new generation of our cost-effective, tens-of-thousands-scalable cluster network architecture. Some test results and characterization of data transmission of a complete testbench, based on a commercial development card mounting an Altera{sup Registered-Sign} FPGA, are provided.

Advanced Detectors for Nuclear, High Energy and Astroparticle Physics

CERN Document Server

Das, Supriya; Ghosh, Sanjay

2018-01-01

The book presents high-quality papers presented at a national conference on ‘Advanced Detectors for Nuclear, High Energy and Astroparticle Physics’. The conference was organized to commemorate 100 years of Bose Institute. The book is based on the theme of the conference and provides a clear picture of basics and advancement of detectors for nuclear physics, high-energy physics and astroparticle physics together. The topics covered in the book include detectors for accelerator-based high energy physics; detectors for non-accelerator particle physics; nuclear physics detectors; detection techniques in astroparticle physics and dark matter; and applications and simulations. The book will be a good reference for researchers and industrial personnel working in the area of nuclear and astroparticle physics.

Bandwidth-on-demand motion control

NARCIS (Netherlands)

Van Loon, S.J.L.M.; Hunnekens, B.G.B.; Simon, A.S.; van de Wouw, N.; Heemels, W.P.M.H.

2018-01-01

In this brief, we introduce a 'bandwidth-on-demand' variable-gain control (VGC) strategy that allows for a varying bandwidth of the feedback controller. The proposed VGC can achieve improved performance given time-varying, reference-dependent performance requirements compared with linear

Development of high sensitivity radon detectors

CERN Document Server

Takeuchi, Y; Kajita, T; Tasaka, S; Hori, H; Nemoto, M; Okazawa, H

1999-01-01

High sensitivity detectors for radon in air and in water have been developed. We use electrostatic collection and a PIN photodiode for these detectors. Calibration systems have been also constructed to obtain collection factors. As a result of the calibration study, the absolute humidity dependence of the radon detector for air is clearly observed in the region less than about 1.6 g/m sup 3. The calibration factors of the radon detector for air are 2.2+-0.2 (counts/day)/(mBq/m sup 3) at 0.08 g/m sup 3 and 0.86+-0.06 (counts/day)/(mBq/m sup 3) at 11 g/m sup 3. The calibration factor of the radon detector for water is 3.6+-0.5 (counts/day)/(mBq/m sup 3). The background level of the radon detector for air is 2.4+-1.3 counts/day. As a result, one standard deviation excess of the signal above the background of the radon detector for air should be possible for 1.4 mBq/m sup 3 in a one-day measurement at 0.08 g/m sup 3.

Development of a high-count-rate neutron detector with position sensitivity and high efficiency

International Nuclear Information System (INIS)

Nelson, R.; Sandoval, J.

1996-01-01

While the neutron scattering community is bombarded with hints of new technologies that may deliver detectors with high-count-rate capability, high efficiency, gamma-ray insensitivity, and high resolution across large areas, only the time-tested, gas-filled 3 He and scintillation detectors are in widespread use. Future spallation sources with higher fluxes simply must exploit some of the advanced detector schemes that are as yet unproved as production systems. Technologies indicating promise as neutron detectors include pixel arrays of amorphous silicon, silicon microstrips, microstrips with gas, and new scintillation materials. This project sought to study the competing neutron detector technologies and determine which or what combination will lead to a production detector system well suited for use at a high-intensity neutron scattering source

A detector for high-energy neutrino interactions

International Nuclear Information System (INIS)

Holder, M.; Knobloch, J.; Lacourt, A.; Laverriere, G.; May, J.; Paar, H.; Palazzi, P.; Ranjard, F.; Schilly, P.; Schlatter, D.; Steinberger, J.; Suter, H.; Wahl, H.; Williams, E.G.H.; Eisele, F.; Geweniger, G.; Kleinknecht, K.; Pollmann, O.; Spahn, G.; Willutzki, H.J.; Navarria, F.L.

1978-01-01

The authors describe the design, construction and performance of a large mass detector used at CERN to study high-energy neutrino interactions in iron. This detector combines magnetic spectrometry and hadron calorimetry techniques. (Auth.)

Digital readouts for large microwave low-temperature detector arrays

International Nuclear Information System (INIS)

Mazin, Benjamin A.; Day, Peter K.; Irwin, Kent D.; Reintsema, Carl D.; Zmuidzinas, Jonas

2006-01-01

Over the last several years many different types of low-temperature detectors (LTDs) have been developed that use a microwave resonant circuit as part of their readout. These devices include microwave kinetic inductance detectors (MKID), microwave SQUID readouts for transition edge sensors (TES), and NIS bolometers. Current readout techniques for these devices use analog frequency synthesizers and IQ mixers. While these components are available as microwave integrated circuits, one set is required for each resonator. We are exploring a new readout technique for this class of detectors based on a commercial-off-the-shelf technology called software defined radio (SDR). In this method a fast digital to analog (D/A) converter creates as many tones as desired in the available bandwidth. Our prototype system employs a 100MS/s 16-bit D/A to generate an arbitrary number of tones in 50MHz of bandwidth. This signal is then mixed up to the desired detector resonant frequency (∼10GHz), sent through the detector, then mixed back down to baseband. The baseband signal is then digitized with a series of fast analog to digital converters (80MS/s, 14-bit). Next, a numerical mixer in a dedicated integrated circuit or FPGA mixes the resonant frequency of a specified detector to 0Hz, and sends the complex detector output over a computer bus for processing and storage. In this paper we will report on our results in using a prototype system to readout a MKID array, including system noise performance, X-ray pulse response, and cross-talk measurements. We will also discuss how this technique can be scaled to read out many thousands of detectors

The ATLAS High-Granularity Timing Detector

CERN Document Server

Sacerdoti, Sabrina; The ATLAS collaboration

2018-01-01

In the high luminosity phase of the LHC, scheduled to start in 2026, the instantaneous luminosity will be increased to up to $\\mathcal{L} = 7.5 × 10^{34} cm^{−2}s^{−1}$. As a consequence, the detectors will be faced with challenging conditions, in particular the increase of pile-up: an average of 200 interactions per bunch crossing are expected, corresponding to an average interaction density of 1.8 collisions/mm. The reconstruction performance will be severely degraded in the end-cap and forward region of the ATLAS detector, especially for jets and transverse missing energy. The addition of timing information in forward objects through the High-Granularity Timing Detector will help to recover the performance of these regions to levels similar to the ones expected in the central region of the detector. It will also provide a bunch-by-bunch luminosity measurement. This talk will be focused on the developments surrounding the LGAD sensors and front-end electronics, which are aimed to achieve a low time res...

Glass Industry Bandwidth Analysis

Energy Technology Data Exchange (ETDEWEB)

Rue, David M. [Gas Technology Inst., Des Plaines, IL (United States)

2006-07-01

This is a study on energy use and potential savings, or "bandwidth" study, for several glassmaking processes. Intended to provide a realistic estimate of the potential amount of energy that can be saved in an industrial process, the "bandwidth" refers to the difference between the amount of energy that would be consumed in a process using commercially available technology versus the minimum amount of energy needed to achieve those same results.

Industrial Glass Bandwidth Analysis

Energy Technology Data Exchange (ETDEWEB)

Rue, David M. [Gas Technology Inst., Des Plaines, IL (United States); Servaites, James [Gas Technology Inst., Des Plaines, IL (United States); Wolf, Warren [Gas Technology Inst., Des Plaines, IL (United States)

2007-08-01

This is a study on energy use and potential savings, or "bandwidth" study, for several glassmaking processes. Intended to provide a realistic estimate of the potential amount of energy that can be saved in an industrial process, the "bandwidth" refers to the difference between the amount of energy that would be consumed in a process using commercially available technology versus the minimum amount of energy needed to achieve those same results.

Performance characterization of the Micromegas detector for the New Small Wheel upgrade and Development and improvement of the Muon Spectrometer Detector Control System in the ATLAS experiment

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00349891

The ATLAS, an abbreviation for A Toroidal LHC ApparatuS, detector is one of the two general purpose high luminosity experiments (along with CMS) that have been built for probing p-p and Pb-Pb or p-Pb collisions in the LHC. The muon spectrometer encircles the rest of the ATLAS detector subsystems defining the ATLAS overall dimensions. Its principle of operation is based on the magnetic deflection of muon tracks by a system of superconducting air-core toroid magnets providing high resolution muon momentum measurement. The upgrade of the ATLAS muon spectrometer is primarily motivated by the high background radiation expected during Run-3 (2021) and ultimately at $\\mathcal{L}=7\\times 10^{34}\\,\\mathrm{cm^{-2}s^{-1}}$ in HL-LHC (2026). Owing to this the detectors that occupy the innermost muon station called Small Wheel (SW), MDT, CSC \\& TGC, will go beyond their design luminosity limit. In addition, the muon trigger rate will exceed the available bandwidth because of the fake endcap muon triggers ($90\\%$ is c...

Optimal Bandwidth Selection for Kernel Density Functionals Estimation

Directory of Open Access Journals (Sweden)

Su Chen

2015-01-01

Full Text Available The choice of bandwidth is crucial to the kernel density estimation (KDE and kernel based regression. Various bandwidth selection methods for KDE and local least square regression have been developed in the past decade. It has been known that scale and location parameters are proportional to density functionals ∫γ(xf2(xdx with appropriate choice of γ(x and furthermore equality of scale and location tests can be transformed to comparisons of the density functionals among populations. ∫γ(xf2(xdx can be estimated nonparametrically via kernel density functionals estimation (KDFE. However, the optimal bandwidth selection for KDFE of ∫γ(xf2(xdx has not been examined. We propose a method to select the optimal bandwidth for the KDFE. The idea underlying this method is to search for the optimal bandwidth by minimizing the mean square error (MSE of the KDFE. Two main practical bandwidth selection techniques for the KDFE of ∫γ(xf2(xdx are provided: Normal scale bandwidth selection (namely, “Rule of Thumb” and direct plug-in bandwidth selection. Simulation studies display that our proposed bandwidth selection methods are superior to existing density estimation bandwidth selection methods in estimating density functionals.

High Temperature Superconductor Resonator Detectors

Data.gov (United States)

National Aeronautics and Space Administration — High Temperature Superconductor (HTS) infrared detectors were studied for years but never matured sufficiently for infusion into instruments. Several recent...

A beam-synchronous gated peak-detector for the LHC beam observation system

CERN Document Server

Levens, T E; Wehrle, U

2013-01-01

Measurements of the bunch peak amplitude using the longitudinal wideband wall-current monitor are a vital tool used in the Large Hadron Collider (LHC) beam observation system. These peak-detected measurements can be used to diagnose bunch shape oscillations, for example coherent quadrupole oscillations, that occur at injection and during beam manipulations. Peak-detected Schottky diagnostics can also be used to obtain the synchrotron frequency distribution and other parameters from a bunched beam under stable conditions. For the LHC a beam-synchronous gated peak detector has been developed to allow individual bunches to be monitored without the influence of other bunches circulating in the machine. The requirement for the observation of both low intensity pilot bunches and high intensity bunches for physics requires a detector front-end with a high bandwidth and a large dynamic range while the usage for Schottky measurements requires low noise electronics. This paper will present the design of this detector s...

High speed optical wireless data transmission system for particle sensors in high energy physics

Science.gov (United States)

Ali, W.; Corsini, R.; Ciaramella, E.; Dell'Orso, R.; Messineo, A.; Palla, F.

2015-08-01

High speed optical fiber or copper wire communication systems are frequently deployed for readout data links used in particle physics detectors. Future detector upgrades will need more bandwidth for data transfer, but routing requirements for new cables or optical fiber will be challenging due to space limitations. Optical wireless communication (OWC) can provide high bandwidth connectivity with an advantage of reduced material budget and complexity of cable installation and management. In a collaborative effort, Scuola Superiore Sant'Anna and INFN Pisa are pursuing the development of a free-space optical link that could be installed in a future particle physics detector or upgrade. We describe initial studies of an OWC link using the inner tracker of the Compact Muon Solenoid (CMS) detector as a reference architecture. The results of two experiments are described: the first to verify that the laser source transmission wavelength of 1550 nm will not introduce fake signals in silicon strip sensors while the second was to study the source beam diameter and its tolerance to misalignment. For data rates of 2.5 Gb/s and 10 Gb/s over a 10 cm working distance it was observed that a tolerance limit of ±0.25 mm to ±0.8 mm can be obtained for misaligned systems with source beam diameters of 0.38 mm to 3.5 mm, respectively.

Hydrogen high pressure proportional drift detector

International Nuclear Information System (INIS)

Arefiev, A.; Balaev, A.

1983-01-01

The design and operation performances of a proportional drift detector PDD are described. High sensitivity of the applied PAD makes it possible to detect the neutron-proton elastic scattering in the energy range of recoil protons as low as 1 keV. The PDD is filled with hydrogen up to the pressure at 40 bars. High purity of the gas is maintained by a continuously operating purification system. The detector has been operating for several years in a neutron beam at the North Area of the CERN SPS

CZT drift strip detectors for high energy astrophysics

DEFF Research Database (Denmark)

Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Caroli, E.

2010-01-01

Requirements for X- and gamma ray detectors for future High Energy Astrophysics missions include high detection efficiency and good energy resolution as well as fine position sensitivity even in three dimensions.We report on experimental investigations on the CZT drift detector developed DTU Space...

Reliability studies of high operating temperature MCT photoconductor detectors

Science.gov (United States)

Wang, Wei; Xu, Jintong; Zhang, Yan; Li, Xiangyang

2010-10-01

This paper concerns HgCdTe (MCT) infrared photoconductor detectors with high operating temperature. The near room temperature operation of detectors have advantages of light weight, less cost and convenient usage. Their performances are modest and they suffer from reliable problems. These detectors face with stability of the package, chip bonding area and passivation layers. It's important to evaluate and improve the reliability of such detectors. Defective detectors were studied with SEM(Scanning electron microscope) and microscopy. Statistically significant differences were observed between the influence of operating temperature and the influence of humidity. It was also found that humility has statistically significant influence upon the stability of the chip bonding and passivation layers, and the amount of humility isn't strongly correlated to the damage on the surface. Considering about the commonly found failures modes in detectors, special test structures were designed to improve the reliability of detectors. An accelerated life test was also implemented to estimate the lifetime of the high operating temperature MCT photoconductor detectors.

Improving the Bandwidth Selection in Kernel Equating

Science.gov (United States)

Andersson, Björn; von Davier, Alina A.

2014-01-01

We investigate the current bandwidth selection methods in kernel equating and propose a method based on Silverman's rule of thumb for selecting the bandwidth parameters. In kernel equating, the bandwidth parameters have previously been obtained by minimizing a penalty function. This minimization process has been criticized by practitioners…

The statistical bandwidth of Butterworth filters

Science.gov (United States)

Davy, J. L.; Dunn, I. P.

1987-06-01

The precision of standard architectural acoustic measurements is a function of the statistical bandwidth of the band pass filters used in the measurements. The International and United States Standards on octave and fractional octave-band filters which specify the band pass filters used in architectural acoustics measurements give the effective bandwidth, but unfortunately not the statistical bandwidth of the filters. Both these Standards are currently being revised and both revisions require the use of Butterworth filter characteristics. In this paper it is shown theoretically that the ratio of statistical bandwidth to effective bandwidth for an nth order Butterworth band pass filter is {2n}/{(2n-1)}. This is verified experimentally for third-octave third-order Butterworth band pass filters. It is also shown experimentally that this formula is approximately correct for some non-Butterworth third-octave third-order band pass filters. Because of the importance of Butterworth filters in the revised Standards, the theory of Butterworth filters is reviewed and the formulae for Butterworth filters given in both revised Standards are derived.

Strip detector for the ATLAS detector upgrade for the high-luminosity LHC

CERN Document Server

Madaffari, Daniele; The ATLAS collaboration

2017-01-01

The planned HL-LHC (High Luminosity LHC) in 2025 is being designed to maximise the physics potential of the LHC through a sizeable increase in the luminosity, reaching 1x10$^{35}$ cm$^{-2}$s$^{-1}$ after 10 years of operation. A consequence of this increased luminosity is the expected radiation damage at an integrated luminosity of 3000 fb$^{-1}$, requiring the tracking detectors to withstand hadron fluencies to over 1x10$^{16}$ 1 MeV neutron equivalent per cm$^2$. With the addition of increased readout rates, a complete re-design of the current ATLAS Inner Detector (ID) is being developed as the Inner Tracker (ITk), which will consist of both strip and pixelated silicon detectors. The physics motivations, required performance characteristics and basic design of the proposed upgrade of the strip detector will be a subject of this talk. Present ideas and solutions for the strip detector and current research and development program will be discussed.

Prototyping of larger structures for the Phase-II upgrade of the pixel detector of the ATLAS experiment

CERN Document Server

Alvarez Feito, Diego; The ATLAS collaboration

2017-01-01

For the high luminosity era of the Large Hadron Collider (HL-LHC) it is forseen to replace the current inner tracker of the ATLAS experiment with a new detector to cope with the occuring increase in occupancy, bandwidth and radiation damage. It will consist of an inner pixel and outer strip detector aiming to provide tracking coverage up to |η|<4. The layout of the pixel detector is foreseen to consist of five layers of pixel silicon sensor modules in the central region and several ring-shaped layers in the forward region. It results in up to 14 m² of silicon depending on the selected layout. Beside the challenge of radiation hardness and high-rate capable silicon sensors and readout electronics many system aspects have to be considered for a fully functional detector. Both stable and low mass mechanical structures and services are important. Within the collaboration a large effort is started to prototype larger detector structures for both the central and forward region of the detector. The aspect of sy...

Compensation of the detector capacitance presented to charge-sensitive preamplifiers using the Miller effect

Energy Technology Data Exchange (ETDEWEB)

Kwon, Inyong, E-mail: iykwon@umich.edu [University of Michigan, Ann Arbor, MI (United States); Kang, Taehoon, E-mail: thnkang@umich.edu [University of Michigan, Ann Arbor, MI (United States); Wells, Byron T., E-mail: wells@galtresearch.com [Galt LLC, Ypsilanti, MI (United States); D’Aries, Lawrence J., E-mail: lawrence.j.daries.civ@mail.mil [Picatinny Arsenal, Rockaway Township, NJ (United States); Hammig, Mark D., E-mail: hammig@umich.edu [University of Michigan, Ann Arbor, MI (United States)

2015-06-01

This paper describes an integrated circuit design for a modified charge-sensitive amplifier (CSA) that compensates for the effect of capacitance presented by nuclear radiation detectors and other sensors. For applications that require large area semiconductor detectors or for those semiconductor sensors derived from high permittivity materials such as PbSe, the detector capacitance can degrade the system gain and bandwidth of a front-end preamplifier, resulting in extended rise times and attenuated output voltage signals during pulse formation. In order to suppress the effect of sensor capacitance, we applied a bootstrap technique into a traditional CSA. The technique exploits the Miller effect by reducing the effective voltage difference between the two sides of a radiation detector which minimizes the capacitance presented to the differential common-source amplifier. This new configuration is successfully designed to produce effective gain even at high detector capacitance. The entire circuit, including a core CSA with feedback components and a bootstrap amplifier, are implemented in a 0.18 μm CMOS process with a 3.3 V supply voltage. - Highlights: • A modified CSA was implemented for detector capacitance compensation. • Increasing detector capacitance degrades gain and rise time. • A bootstrap amplifier exploiting the Miller effect is described. • It allows using large area radiation sensors for high radiation-interaction rates. • Intensive noise analyses show that SNR is much better with the technique.

Bandwidth tunable amplifier for recording biopotential signals.

Science.gov (United States)

Hwang, Sungkil; Aninakwa, Kofi; Sonkusale, Sameer

2010-01-01

This paper presents a low noise, low power, bandwidth tunable amplifier for bio-potential signal recording applications. By employing depletion-mode pMOS transistor in diode configuration as a tunable sub pA current source to adjust the resistivity of MOS-Bipolar pseudo-resistor, the bandwidth is adjusted without any need for a separate band-pass filter stage. For high CMRR, PSRR and dynamic range, a fully differential structure is used in the design of the amplifier. The amplifier achieves a midband gain of 39.8dB with a tunable high-pass cutoff frequency ranging from 0.1Hz to 300Hz. The amplifier is fabricated in 0.18εm CMOS process and occupies 0.14mm(2) of chip area. A three electrode ECG measurement is performed using the proposed amplifier to show its feasibility for low power, compact wearable ECG monitoring application.

Event timing in high purity germanium coaxial detectors

International Nuclear Information System (INIS)

El-Ibiary, M.Y.

1979-08-01

The timing of gamma ray radiation in systems using high purity coaxial germanium detectors is analyzed and compared to that of systems using Ge(Li) detectors. The analysis takes into account the effect of the residual impurities on the electric field distribution, and hence on the rate of rise of the electrical pulses delivered to the timing module. Conditions under which the electric field distribution could lead to an improvement in timing performance, are identified. The results of the analysis confirm the experimental results published elsewhere and when compared with those for Ge(Li) detectors, which usually operate under conditions of charge carrier velocity saturation, confirm that high purity germanium detectors need not have inferior timing characteristics. A chart is given to provide a quantitative basis on which the trade off between the radius of the detector and its time resolution may be made

High-gain bipolar detector on float-zone silicon

Science.gov (United States)

Han, D. J.; Batignani, G.; Del Guerra, A.; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

2003-10-01

Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ˜7.77×10 4/s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device.

High-gain bipolar detector on float-zone silicon

International Nuclear Information System (INIS)

Han, D.J.; Batignani, G.; Guerra, A.D.A. Del; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

2003-01-01

Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ∼7.77x10 4 /s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device

Time-optimal control with finite bandwidth

Science.gov (United States)

Hirose, M.; Cappellaro, P.

2018-04-01

Time-optimal control theory provides recipes to achieve quantum operations with high fidelity and speed, as required in quantum technologies such as quantum sensing and computation. While technical advances have achieved the ultrastrong driving regime in many physical systems, these capabilities have yet to be fully exploited for the precise control of quantum systems, as other limitations, such as the generation of higher harmonics or the finite response time of the control apparatus, prevent the implementation of theoretical time-optimal control. Here we present a method to achieve time-optimal control of qubit systems that can take advantage of fast driving beyond the rotating wave approximation. We exploit results from time-optimal control theory to design driving protocols that can be implemented with realistic, finite-bandwidth control fields, and we find a relationship between bandwidth limitations and achievable control fidelity.

Proposal for a semiconductor high resolution tracking detector

International Nuclear Information System (INIS)

Rehak, P.

1983-01-01

A 'new' concept for detection and tracking of charged particles in high energy physics experiments is proposed. It combines a well known high purity semiconductor diode detector (HPSDD) with a heterojunction structure (HJ) and a negative electron affinity (NEA) surface. The detector should be capable of providing a two dimensional view (few cm 2 ) of multi-track events with the following properties: a) position resolution down to a few μm (10 8 position elements); b) high density of information (10 2 -10 3 dots per mm of minimum ionizing track); c) high rate capabilities (few MHz); d) live operation with options to be triggered and/or the information from the detector can be used as an input for the decision to record an event. (orig.)

Summary of activity. Topic I: detectors and experiments. [High-energy detectors for use at ISABELLE

Energy Technology Data Exchange (ETDEWEB)

Marx, J; Ozaki, S

1978-01-01

Results of a workshop studying detectors for Isabelle experimental halls are described. The detectors must be very reliable. Spatial resolution of the tracking detectors must be high to provide accurate measurements of angle and momentum, retain a short resolving time, and show excellent multiparticle handling capability. Included in the study were hodoscopes, drift chambers, proportional chambers, time projection chambers, Cherenkov counters, electromagnetic shower detectors, and hadron calorimeters. Data handling methods were also included in the studies. (FS)

47 CFR 2.202 - Bandwidths.

Science.gov (United States)

2010-10-01

... three numerals and one letter. The letter occupies the position of the decimal point and represents the... quality desired Speech and music, M=4000, Bandwidth: 8000 Hz= 8 kHz 8K00A3E Sound broadcasting, single... desired Speech and music, M=4000, Bandwidth: 4000 Hz= 4 kHz 4K00R3E Sound broadcasting, single-sideband...

A Very High Momentum Particle Identification Detector

CERN Document Server

Acconcia, T.V.; Barile, F.; Barnaföldi, G.G.; Bellwied, R.; Bencedi, G.; Bencze, G.; Berenyi, D.; Boldizsar, L.; Chattopadhyay, S.; Cindolo, F.; Chinellato, D.D.; D'Ambrosio, S.; Das, D.; Das, K.; Das-Bose, L.; Dash, A.K.; De Cataldo, G.; De Pasquale, S.; Di Bari, D.; Di Mauro, A.; Futo, E.; Garcia, E.; Hamar, G.; Harton, A.; Iannone, G.; Jimenez, R.T.; Kim, D.W.; Kim, J.S.; Knospe, A.; Kovacs, L.; Levai, P.; Nappi, E.; Markert, C.; Martinengo, P.; Mayani, D.; Molnar, L.; Olah, L.; Paic, G.; Pastore, C.; Patimo, G.; Patino, M.E.; Peskov, V.; Pinsky, L.; Piuz, F.; Pochybova, S.; Sgura, I.; Sinha, T.; Song, J.; Takahashi, J.; Timmins, A.; Van Beelen, J.B.; Varga, D.; Volpe, G.; Weber, M.; Xaplanteris, L.; Yi, J.; Yoo, I.K.

2014-01-01

The construction of a new detector is proposed to extend the capabilities of ALICE in the high transverse momentum (pT) region. This Very High Momentum Particle Identification Detector (VHMPID) performs charged hadron identification on a track-by-track basis in the 5 GeV/c < p < 25 GeV/c momentum range and provides ALICE with new opportunities to study parton-medium interactions at LHC energies. The VHMPID covers up to 30% of the ALICE central barrel and presents sufficient acceptance for triggered- and tagged-jet studies, allowing for the first time identified charged hadron measurements in jets. This Letter of Intent summarizes the physics motivations for such a detector as well as its layout and integration into ALICE.

A high-speed, eight-wavelength visible light-infrared pyrometer for shock physics experiments

Science.gov (United States)

Wang, Rongbo; Li, Shengfu; Zhou, Weijun; Luo, Zhen-Xiong; Meng, Jianhua; Tian, Jianhua; He, Lihua; Cheng, Xianchao

2017-09-01

An eight-channel, high speed pyrometer for precise temperature measurement is designed and realized in this work. The addition of longer-wavelength channels sensitive at lower temperatures highly expands the measured temperature range, which covers the temperature of interest in shock physics from 1500K-10000K. The working wavelength range is 400-1700nm from visible light to near-infrared (NIR). Semiconductor detectors of Si and InGaAs are used as photoelectric devices, whose bandwidths are 50MHz and 150MHz respectively. Benefitting from the high responsivity and high speed of detectors, the time resolution of the pyrometer can be smaller than 10ns. By combining the high-transmittance beam-splitters and narrow-bandwidth filters, the peak spectrum transmissivity of each channel can be higher than 60%. The gray-body temperatures of NaI crystal under shock-loading are successfully measured by this pyrometer.

A VME-based readout system for the CMS Preshower sub-detector

CERN Document Server

Antchev, G; Bialas, W; Da Silva, J C; Kokkas, P; Manthos, N; Reynaud, S; Sidiropoulos, G; Snoeys, W; Vichoudis, P

2007-01-01

The CMS preshower is a fine grain detector that comprises 4288 silicon sensors, each containing 32 strips. The raw data are transferred from the detector to the counting room via 1208 optical fibres. Each fibre carries a 600-byte data packet per event. The maximum average level-1 trigger rate of 100 kHz results in a total data flow of ~72 GB/s from the preshower. For the readout of the preshower, 56 links to the CMS DAQ have been reserved, each having a bandwidth of 200 MB/s (2 kB/event). The total available downstream bandwidth of GB/s necessitates a reduction in the data volume by a factor of at least 7. A modular VME-based system is currently under development. The main objective of each VME board in this system is to acquire on-detector data from at least 22 optical links, perform on-line data reduction and pass the concentrated data to the CMS DAQ. The principle modules that the system is based on are being developed in collaboration with the TOTEM experiment.

High-precision efficiency calibration of a high-purity co-axial germanium detector

Energy Technology Data Exchange (ETDEWEB)

Blank, B., E-mail: blank@cenbg.in2p3.fr [Centre d' Etudes Nucléaires de Bordeaux Gradignan, UMR 5797, CNRS/IN2P3, Université de Bordeaux, Chemin du Solarium, BP 120, 33175 Gradignan Cedex (France); Souin, J.; Ascher, P.; Audirac, L.; Canchel, G.; Gerbaux, M.; Grévy, S.; Giovinazzo, J.; Guérin, H.; Nieto, T. Kurtukian; Matea, I. [Centre d' Etudes Nucléaires de Bordeaux Gradignan, UMR 5797, CNRS/IN2P3, Université de Bordeaux, Chemin du Solarium, BP 120, 33175 Gradignan Cedex (France); Bouzomita, H.; Delahaye, P.; Grinyer, G.F.; Thomas, J.C. [Grand Accélérateur National d' Ions Lourds, CEA/DSM, CNRS/IN2P3, Bvd Henri Becquerel, BP 55027, F-14076 CAEN Cedex 5 (France)

2015-03-11

A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and γ-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived online sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed β decays for tests of the weak-interaction standard model.

High Frequency Amplitude Detector for GMI Magnetic Sensors

Directory of Open Access Journals (Sweden)

Aktham Asfour

2014-12-01

Full Text Available A new concept of a high-frequency amplitude detector and demodulator for Giant-Magneto-Impedance (GMI sensors is presented. This concept combines a half wave rectifier, with outstanding capabilities and high speed, and a feedback approach that ensures the amplitude detection with easily adjustable gain. The developed detector is capable of measuring high-frequency and very low amplitude signals without the use of diode-based active rectifiers or analog multipliers. The performances of this detector are addressed throughout the paper. The full circuitry of the design is given, together with a comprehensive theoretical study of the concept and experimental validation. The detector has been used for the amplitude measurement of both single frequency and pulsed signals and for the demodulation of amplitude-modulated signals. It has also been successfully integrated in a GMI sensor prototype. Magnetic field and electrical current measurements in open- and closed-loop of this sensor have also been conducted.

Optimization of Quantum-Dot Molecular Beam Epitaxy for Broad Spectral Bandwidth Devices

KAUST Repository

Majid, Mohammed Abdul

2012-12-01

The optimization of the key growth parameters for broad spectral bandwidth devices based on quantum dots is reported. A combination of atomic force microscopy, photoluminescence of test samples, and optoelectronic characterization of superluminescent diodes (SLDs) is used to optimize the growth conditions to obtain high-quality devices with large spectral bandwidth, radiative efficiency (due to a reduced defective-dot density), and thus output power. The defective-dot density is highlighted as being responsible for the degradation of device performance. An SLD device with 160 nm of bandwidth centered at 1230 nm is demonstrated.

Optimization of Quantum-Dot Molecular Beam Epitaxy for Broad Spectral Bandwidth Devices

KAUST Repository

Majid, Mohammed Abdul; Hugues, M.; Vézian, S.; Childs, D. T. D.; Hogg, R. A.

2012-01-01

The optimization of the key growth parameters for broad spectral bandwidth devices based on quantum dots is reported. A combination of atomic force microscopy, photoluminescence of test samples, and optoelectronic characterization of superluminescent diodes (SLDs) is used to optimize the growth conditions to obtain high-quality devices with large spectral bandwidth, radiative efficiency (due to a reduced defective-dot density), and thus output power. The defective-dot density is highlighted as being responsible for the degradation of device performance. An SLD device with 160 nm of bandwidth centered at 1230 nm is demonstrated.

The data acquisition system of the Belle II Pixel Detector

Science.gov (United States)

Münchow, D.; Dingfelder, J.; Geßler, T.; Konorov, I.; Kühn, W.; Lange, S.; Lautenbach, K.; Levit, D.; Liu, Z.; Marinas, C.; Schnell, M.; Spruck, B.; Zhao, J.

2014-08-01

At the future Belle II experiment the DEPFET (DEPleted Field Effect Transistor) pixel detector will consist of about 8 million channels and is placed as the innermost detector. Because of its small distance to the interaction region and the high luminosity in Belle II, for a trigger rate of about 30 kHz with an estimated occupancy of about 3 % a data rate of about 22 GB/s is expected. Due to the high data rate, a data reduction factor higher than 30 is needed in order to stay inside the specifications of the event builder. The main hardware to reduce the data rate is a xTCA based Compute Node (CN) developed in cooperation between IHEP Beijing and University Giessen. Each node has as main component a Xilinx Virtex-5 FX70T FPGA and is equipped with 2 × 2 GB RAM , GBit Ethernet and 4 × 6.25 Gb/s optical links. An ATCA carrier board is able to hold up to four CN and supplies high bandwidth connections between the four CNs and to the ATCA backplane. To achieve the required data reduction on the CNs, regions of interest (ROI) are used. These regions are calculated in two independent systems by projecting tracks back to the pixel detector. One is the High Level Trigger (HLT) which uses data from the Silicon Vertex Detector (SVD), a silicon strip detector, and outer detectors. The other is the Data Concentrator (DATCON) which calculates ROIs based on SVD data only, in order to get low momentum tracks. With this information, only PXD data inside these ROIs will be forwarded to the event builder, while data outside of these regions will be discarded. First results of the test beam time in January 2014 at DESY with a Belle II vertex detector prototype and full DAQ chain will be presented.

Controlling Laser Plasma Instabilities Using Temporal Bandwidth

Science.gov (United States)

Tsung, Frank; Weaver, J.; Lehmberg, R.

2016-10-01

We are performing particle-in-cell simulations using the code OSIRIS to study the effects of laser plasma interactions in the presence of temporal bandwidth under conditions relevant to current and future experiments on the NIKE laser. Our simulations show that, for sufficiently large bandwidth (where the inverse bandwidth is comparable with the linear growth time), the saturation level, and the distribution of hot electrons, can be effected by the addition of temporal bandwidths (which can be accomplished in experiments using beam smoothing techniques such as ISI). We will quantify these effects and investigate higher dimensional effects such as laser speckles. This work is supported by DOE and NRL.

Optoelectronic analogue signal transfer for LHC detectors, 1991

CERN Document Server

Dowell, John D; Homer, R J; Jovanovic, P; Kenyon, I; Staley, R; Webster, K; Da Via, C; Feyt, J; Nappey, P; Stefanini, G; Dwir, B; Reinhart, F K; Davies, J; Green, N; Stewart, W; Young, T; Hall, G; Akesson, T; Jarlskog, G; Kröll, S; Nickerson, R; Jaroslawski, S; CERN. Geneva. Detector Research and Development Committee

1991-01-01

We propose to study and develop opto-electronic analogue front-ends based on electro-optic intensity modulators. These devices translate the detector electrical analogue signals into optical signals which are then transferred via optical fibres to photodetector receivers at the remote readout. In comparison with conventional solutions based on copper cables, this technique offers the advantages of high speed, very low power dissipation and transmission losses, compactness and immunity to electromagnetic interference. The linearity and dynamic range that can be obtained are more than adequate for central tracking detectors, and the proposed devices have considerable radiation- hardness capabilities. The large bandwidth and short transit times offer possibilities for improved triggering schemes. The proposed R&D programme is aimed at producing multi-channel "demonstrator" units for evaluation both in laboratory and beam tests. This will allow the choice of the most effective technology. A detailed study wil...

Receiver bandwidth effects on complex modulation and detection using directly modulated lasers.

Science.gov (United States)

Yuan, Feng; Che, Di; Shieh, William

2016-05-01

Directly modulated lasers (DMLs) have long been employed for short- and medium-reach optical communications due to their low cost. Recently, a new modulation scheme called complex modulated DMLs has been demonstrated showing a significant optical signal to noise ratio sensitivity enhancement compared with the traditional intensity-only detection scheme. However, chirp-induced optical spectrum broadening is inevitable in complex modulated systems, which may imply a need for high-bandwidth receivers. In this Letter, we study the impact of receiver bandwidth effects on the performance of complex modulation and coherent detection systems based on DMLs. We experimentally demonstrate that such systems exhibit a reasonable tolerance for the reduced receiver bandwidth. For 10 Gbaud 4-level pulse amplitude modulation signals, the required electrical bandwidth is as low as 8.5 and 7.5 GHz for 7% and 20% forward error correction, respectively. Therefore, it is feasible to realize DML-based complex modulated systems using cost-effective receivers with narrow bandwidth.

Single photon detector with high polarization sensitivity.

Science.gov (United States)

Guo, Qi; Li, Hao; You, LiXing; Zhang, WeiJun; Zhang, Lu; Wang, Zhen; Xie, XiaoMing; Qi, Ming

2015-04-15

Polarization is one of the key parameters of light. Most optical detectors are intensity detectors that are insensitive to the polarization of light. A superconducting nanowire single photon detector (SNSPD) is naturally sensitive to polarization due to its nanowire structure. Previous studies focused on producing a polarization-insensitive SNSPD. In this study, by adjusting the width and pitch of the nanowire, we systematically investigate the preparation of an SNSPD with high polarization sensitivity. Subsequently, an SNSPD with a system detection efficiency of 12% and a polarization extinction ratio of 22 was successfully prepared.

Fast current amplifier for background-limited operation of photovoltaic InSb detectors

Energy Technology Data Exchange (ETDEWEB)

Altmann, J; Koehler, S; Lahmann, W

1981-01-01

A fast current amplifier for use with photovoltaic indium antimonide detectors is described which was designed for detection of lidar return signals. Near background-limited operation was possible for bandwidths up to 0.8 MHz.

Broadband illumination of superconducting pair breaking photon detectors

International Nuclear Information System (INIS)

Guruswamy, T; Goldie, D J; Withington, S

2016-01-01

Understanding the detailed behaviour of superconducting pair breaking photon detectors such as Kinetic Inductance Detectors (KIDs) requires knowledge of the nonequilibrium quasiparticle energy distributions. We have previously calculated the steady state distributions resulting from uniform absorption of monochromatic sub gap and above gap frequency radiation by thin films. In this work, we use the same methods to calculate the effect of illumination by broadband sources, such as thermal radiation from astrophysical phenomena or from the readout system. Absorption of photons at multiple above gap frequencies is shown to leave unchanged the structure of the quasiparticle energy distribution close to the superconducting gap. Hence for typical absorbed powers, we find the effects of absorption of broadband pair breaking radiation can simply be considered as the sum of the effects of absorption of many monochromatic sources. Distribution averaged quantities, like quasiparticle generation efficiency η, match exactly a weighted average over the bandwidth of the source of calculations assuming a monochromatic source. For sub gap frequencies, however, distributing the absorbed power across multiple frequencies does change the low energy quasiparticle distribution. For moderate and high absorbed powers, this results in a significantly larger η–a higher number of excess quasiparticles for a broadband source compared to a monochromatic source of equal total absorbed power. Typically in KIDs the microwave power absorbed has a very narrow bandwidth, but in devices with broad resonance characteristics (low quality factors), this increase in η may be measurable. (paper)

Open-Loop Wide-Bandwidth Phase Modulation Techniques

Directory of Open Access Journals (Sweden)

Nitin Nidhi

2011-01-01

Full Text Available The ever-increasing growth in the bandwidth of wireless communication channels requires the transmitter to be wide-bandwidth and power-efficient. Polar and outphasing transmitter topologies are two promising candidates for such applications, in future. Both these architectures require a wide-bandwidth phase modulator. Open-loop phase modulation presents a viable solution for achieving wide-bandwidth operation. An overview of prior art and recent approaches for phase modulation is presented in this paper. Phase quantization noise cancellation was recently introduced to lower the out-of-band noise in a digital phase modulator. A detailed analysis on the impact of timing and quantization of the cancellation signal is presented. Noise generated by the transmitter in the receive band frequency poses another challenge for wide-bandwidth transmitter design. Addition of a noise transfer function notch, in a digital phase modulator, to reduce the noise in the receive band during phase modulation is described in this paper.

A high performance long-reach passive optical network with a novel excess bandwidth distribution scheme

Science.gov (United States)

Chao, I.-Fen; Zhang, Tsung-Min

2015-06-01

Long-reach passive optical networks (LR-PONs) have been considered to be promising solutions for future access networks. In this paper, we propose a distributed medium access control (MAC) scheme over an advantageous LR-PON network architecture that reroutes the control information from and back to all ONUs through an (N + 1) × (N + 1) star coupler (SC) deployed near the ONUs, thereby overwhelming the extremely long propagation delay problem in LR-PONs. In the network, the control slot is designed to contain all bandwidth requirements of all ONUs and is in-band time-division-multiplexed with a number of data slots within a cycle. In the proposed MAC scheme, a novel profit-weight-based dynamic bandwidth allocation (P-DBA) scheme is presented. The algorithm is designed to efficiently and fairly distribute the amount of excess bandwidth based on a profit value derived from the excess bandwidth usage of each ONU, which resolves the problems of previously reported DBA schemes that are either unfair or inefficient. The simulation results show that the proposed decentralized algorithms exhibit a nearly three-order-of-magnitude improvement in delay performance compared to the centralized algorithms over LR-PONs. Moreover, the newly proposed P-DBA scheme guarantees low delay performance and fairness even when under attack by the malevolent ONU irrespective of traffic loads and burstiness.

The High Energy Detector of Simbol-X

Science.gov (United States)

Meuris, A.; Limousin, O.; Lugiez, F.; Gevin, O.; Blondel, C.; Le Mer, I.; Pinsard, F.; Cara, C.; Goetschy, A.; Martignac, J.; Tauzin, G.; Hervé, S.; Laurent, P.; Chipaux, R.; Rio, Y.; Fontignie, J.; Horeau, B.; Authier, M.; Ferrando, P.

2009-05-01

The High Energy Detector (HED) is one of the three detection units on board the Simbol-X detector spacecraft. It is placed below the Low Energy Detector so as to collect focused photons in the energy range from 8 to 80 keV. It consists of a mosaic of 64 independent cameras, divided in 8 sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique component. The status of the HED design will be reported. The promising results obtained from the first micro-camera prototypes called Caliste 64 and Caliste 256 will be presented to illustrate the expected performance of the instrument.

The High Energy Detector of Simbol-X

International Nuclear Information System (INIS)

Meuris, A.; Limousin, O.; Blondel, C.; Le Mer, I.; Pinsard, F.; Cara, C.; Goetschy, A.; Martignac, J.; Laurent, P.; Chipaux, R.; Rio, Y.; Fontignie, J.; Horeau, B.; Ferrando, P.; Lugiez, F.; Gevin, O.; Tauzin, G.; Herve, S.; Authier, M.

2009-01-01

The High Energy Detector (HED) is one of the three detection units on board the Simbol-X detector spacecraft. It is placed below the Low Energy Detector so as to collect focused photons in the energy range from 8 to 80 keV. It consists of a mosaic of 64 independent cameras, divided in 8 sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique component. The status of the HED design will be reported. The promising results obtained from the first micro-camera prototypes called Caliste 64 and Caliste 256 will be presented to illustrate the expected performance of the instrument.

Fluid limits for Bandwidth-Sharing Networks with Impatience.

NARCIS (Netherlands)

Remerova, M.; Reed, J.; Zwart, A.P.

2014-01-01

Bandwidth-sharing networks as introduced by Roberts and Massoulié [Roberts JW, Massoulié L (1998) Bandwidth sharing and admission control for elastic traffic. Proc. ITC Specialist Seminar, Yokohama, Japan], Massoulié and Roberts [Massoulié L, Roberts JW (1999) Bandwidth sharing: Objectives and

Directing Traffic: Managing Internet Bandwidth Fairly

Science.gov (United States)

Paine, Thomas A.; Griggs, Tyler J.

2008-01-01

Educational institutions today face budgetary restraints and scarce resources, complicating the decision of how to allot bandwidth for campus network users. Additionally, campus concerns over peer-to-peer networking (specifically outbound Internet traffic) have increased because of bandwidth and copyright issues. In this article, the authors…

The upgrade for the data acquisition system of the KOTO detector

Energy Technology Data Exchange (ETDEWEB)

Tecchio, M., E-mail: tecchio@umich.edu [University of Michigan, Ann Arbor, MI (United States); Beechert, J.; Campbell, M. [University of Michigan, Ann Arbor, MI (United States); Huff, M. [Kenyon College, Gambier, OH (United States); Micallef, J.; Rymph, C.; Schamis, H.; Su, S. [University of Michigan, Ann Arbor, MI (United States); Xu, J. [Apple Inc., Cupertino, CA (United States)

2016-07-11

A major upgrade to the KOTO detector data acquisition system based on the ATCA standard is being considered. The ATCA standard provides a natural solution to the current KOTO constraints, including communication between boards and higher input and output bandwidth.

The upgrade for the data acquisition system of the KOTO detector

International Nuclear Information System (INIS)

Tecchio, M.; Beechert, J.; Campbell, M.; Huff, M.; Micallef, J.; Rymph, C.; Schamis, H.; Su, S.; Xu, J.

2016-01-01

A major upgrade to the KOTO detector data acquisition system based on the ATCA standard is being considered. The ATCA standard provides a natural solution to the current KOTO constraints, including communication between boards and higher input and output bandwidth.

Propagation of 1-THz bandwidth electrical pulses on high Tc superconducting transmission lines

International Nuclear Information System (INIS)

Nuss, M.C.; Mankiewich, P.M.; Howard, R.E.; Harvey, T.E.; Brandle, C.D.; Straugh, B.L.; Smith, P.R.

1989-01-01

The new high temperature superconductors have triggered enormous interest not only because of the unique physics involved but also because of their technical potentials, such as the promise for propagation of extremely short electrical pulses. Superconducting band caps of --20TH z are predicted assuming BCS theory for the superconductor, making lossless propagation of electrical pulses as short as 50 fs possible. Despite microwave measurements at low frequencies of several gigahertz first studies at higher frequencies by Dykaar et al have shown distortion-free propagation of 100-GHz electrical pulses on YBa 2 Cu 3 O 3 (YBCO) lines for --5-mm propagation distance. Results were also reported for aluminum coplanar lines and a YBCO ground plane. The authors report on the propagation of 1-ps electrical pulses (1-THz bandwidth) on YBCO coplanar transmission lines defined on lanthanum gallate (LaGaO 3 ) as a substrate. On LaGaO 3 , YBCO grows highly oriented as on SrTiO 3 . However, unlike SrTiO 3 , LaGaO 3 has a much lower dielectric constant and small losses in the terahertz frequency range. Electrical pulses of --750-fs duration are generated in a radiation-damaged silicon-on-sapphire photoconductive switch integrated into a 20-μm coplanar stripline with 10-μm spacing and excited with 100-fs optical pulses from a CPM laser. An μ1-THz bandwidth electrical contact is made to the YBCO coplanar stripline defined on LaGaO 3 using a flip-chip geometry. They find that electrical pulses broaden only from 750 fs to 1 ps with little loss in amplitude on traveling through their flip-chip input and propagated electrical pulses are probed by electooptic sampling in two small LiTaO 3 crystals separated by 3 mm

Performance of the NOνA Data Acquisition and Trigger Systems for the full 14 kT Far Detector

International Nuclear Information System (INIS)

Norman, A.; Ding, P.F.; Rebel, B.; Shanahan, P.; Davies, G.S.; Niner, E.; Dukes, E.C.; Frank, M.J.; Group, R.C.; Henderson, W.; Mina, R.; Oksuzian, Y.; Duyan, H.; Habig, A.; Moren, A.; Tomsen, K.; Mualem, L.; Sheshukov, A.; Tamsett, M.; Vinton, L.

2015-01-01

The NOvA experiment uses a continuous, free-running, dead-timeless data acquisition system to collect data from the 14 kT far detector. The DAQ system readouts the more than 344,000 detector channels and assembles the information into an raw unfiltered high bandwidth data stream. The NOvA trigger systems operate in parallel to the readout and asynchronously to the primary DAQ readout/event building chain. The data driven triggering systems for NOvA are unique in that they examine long contiguous time windows of the high resolution readout data and enable the detector to be sensitive to a wide range of physics interactions from those with fast, nanosecond scale signals up to processes with long delayed coincidences between hits which occur at the tens of milliseconds time scale. The trigger system is able to achieve a true 100% live time for the detector, making it sensitive to both beam spill related and off-spill physics. (paper)

Silicon detectors for x and gamma-ray with high radiation resistance

International Nuclear Information System (INIS)

Cimpoca, Valerica; Popescu, Ion V.; Ruscu, Radu

2001-01-01

Silicon detectors are widely used in X and gamma-ray spectroscopy for direct detection or coupled with scintillators in high energy nuclear physics (modern collider experiments are representative), medicine and industrial applications. In X and gamma dosimetry, a low detection limit (under 6 KeV) with silicon detectors becomes available. Work at the room temperature is now possible due to the silicon processing evolution, which assures low reverse current and high life time of carriers. For several years, modern semiconductor detectors have been the primary choice for the measurement of nuclear radiation in various scientific fields. Nowadays the recently developed high resolution silicon detectors found their way in medical applications. As a consequence many efforts have been devoted to the development of high sensitivity and radiation hardened X and gamma-ray detectors for the energy range of 5 - 150 keV. The paper presents some results concerning the technology and behaviour of X and Gamma ray silicon detectors used in physics research, industrial and medical radiography. The electrical characteristics of these detectors, their modification after exposure to radiation and the results of spectroscopic X and Gamma-ray measurements are discussed. The results indicated that the proposed detectors enables the development of reliable silicon detectors to be used in controlling the low and high radiation levels encountered in a lot of application

Design and fabrication of bandwidth tunable HTS transmit filter using {pi}-shaped waveguides

Energy Technology Data Exchange (ETDEWEB)

Sekiya, N., E-mail: nsekiya@yamanashi.ac.j [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Harada, H.; Nakagawa, Y. [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ono, S.; Ohshima, S. [Yamagata University, 4-3-16 Johnan, Yonezawa 992-8510 (Japan)

2010-11-01

We have developed a method for tuning the bandwidth of a high-temperature superconducting (HTS) microstrip filter. Several {pi}-shaped waveguides are placed between the resonators, and the bandwidth is tuned in discrete steps by changing the switch states of the waveguides, which changes the coupling coefficient between the resonators. The filter contains 3-pole half-wavelength straight-line resonators and two {pi}-shaped waveguides for bandwidth tuning. It also has several electrical pads distributed around the feed lines for trimming after tuning. The filter was fabricated by depositing YBa{sub 2}Cu{sub 3}O{sub 7} thin film on an MgO substrate and has a measured center frequency of 5.17 GHz and bandwidth of 220 MHz. Use of the {pi}-shaped waveguides to adjust the coupling coefficients and the electrical pads to adjust the external quality factors resulted in 80-MHz bandwidth tuning without increased insertion loss.

A High-Linearity Low-Noise Amplifier with Variable Bandwidth for Neural Recoding Systems

Science.gov (United States)

Yoshida, Takeshi; Sueishi, Katsuya; Iwata, Atsushi; Matsushita, Kojiro; Hirata, Masayuki; Suzuki, Takafumi

2011-04-01

This paper describes a low-noise amplifier with multiple adjustable parameters for neural recording applications. An adjustable pseudo-resistor implemented by cascade metal-oxide-silicon field-effect transistors (MOSFETs) is proposed to achieve low-signal distortion and wide variable bandwidth range. The amplifier has been implemented in 0.18 µm standard complementary metal-oxide-semiconductor (CMOS) process and occupies 0.09 mm2 on chip. The amplifier achieved a selectable voltage gain of 28 and 40 dB, variable bandwidth from 0.04 to 2.6 Hz, total harmonic distortion (THD) of 0.2% with 200 mV output swing, input referred noise of 2.5 µVrms over 0.1-100 Hz and 18.7 µW power consumption at a supply voltage of 1.8 V.

Operational Experience with the ATLAS Pixel Detector

CERN Document Server

Djama, Fares; The ATLAS collaboration

2017-01-01

Run-2 of the LHC is providing new challenges to track and vertex reconstruction imposed by the higher collision energy, pileup and luminosity that are being delivered. The ATLAS tracking performance relies critically on the Pixel Detector, therefore, in view of Run-2 of LHC, the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and an additional optical link per module was added to overcome in some layers the readout bandwidth limitation when LHC will exceed the nominal peak luminosity by almost a factor of 3. The key features and challenges met during the IBL project will be presented, as well as its operational experience and Pixel Detector performance in LHC.

High level trigger system for the ALICE experiment

International Nuclear Information System (INIS)

Frankenfeld, U.; Roehrich, D.; Ullaland, K.; Vestabo, A.; Helstrup, H.; Lien, J.; Lindenstruth, V.; Schulz, M.; Steinbeck, T.; Wiebalck, A.; Skaali, B.

2001-01-01

The ALICE experiment at the Large Hadron Collider (LHC) at CERN will detect up to 20,000 particles in a single Pb-Pb event resulting in a data rate of ∼75 MByte/event. The event rate is limited by the bandwidth of the data storage system. Higher rates are possible by selecting interesting events and subevents (High Level trigger) or compressing the data efficiently with modeling techniques. Both require a fast parallel pattern recognition. One possible solution to process the detector data at such rates is a farm of clustered SMP nodes, based on off-the-shelf PCs, and connected by a high bandwidth, low latency network

tkLayout: a Design Tool for Innovative Silicon Tracking Detectors

CERN Document Server

Bianchi, Giovanni

2014-01-01

A new CMS tracker is scheduled to become operational for the LHC Phase 2 upgrade in the early 2020's. tkLayout is a software package developed to create 3d models for the design of the CMS tracker and to evaluate its fundamental performance figures. The new tracker will have to cope with much higher luminosity conditions, resulting in increased track density, harsher radiation exposure and, especially, much higher data acquisition bandwidth, such that equipping the tracker with triggering capabilities is envisaged. The design of an innovative detector involves deciding on an architecture offering the best trade-off among many figures of merit, such as tracking resolution, power dissipation, bandwidth, cost and so on. Quantitatively evaluating these figures of merit as early as possible in the design phase is of capital importance and it is best done with the aid of software models. tkLayout is a flexible modeling tool: new performance estimates and support for different detector geometries can be quickly ad...

Pseudo-differential CMOS analog front-end circuit for wide-bandwidth optical probe current sensor

Science.gov (United States)

Uekura, Takaharu; Oyanagi, Kousuke; Sonehara, Makoto; Sato, Toshiro; Miyaji, Kousuke

2018-04-01

In this paper, we present a pseudo-differential analog front-end (AFE) circuit for a novel optical probe current sensor (OPCS) aimed for high-frequency power electronics. It employs a regulated cascode transimpedance amplifier (RGC-TIA) to achieve a high gain and a large bandwidth without using an extremely high performance operational amplifier. The AFE circuit is designed in a 0.18 µm standard CMOS technology achieving a high transimpedance gain of 120 dB Ω and high cut off frequency of 16 MHz. The measured slew rate is 70 V/µs and the input referred current noise is 1.02 pA/\\sqrt{\\text{Hz}} . The magnetic resolution and bandwidth of OPCS are estimated to be 1.29 mTrms and 16 MHz, respectively; the bandwidth is higher than that of the reported Hall effect current sensor.

Low and Expensive Bandwidth Remains Key Bottleneck for ...

African Journals Online (AJOL)

These bottlenecks have dwarfed the expectations of the citizens to fully participate in the new world economic order galvanized by e-commerce and world trade. It is estimated that M.I.T in Boston USA has bandwidth allocation that surpasses all the bandwidth allocated to Nigeria put together. Low bandwidth has been found ...

IMPROVING BANDWIDTH OF FLIPPED VOLTAGE FOLLOWER USING GATE-BODY DRIVEN TECHNIQUE

Directory of Open Access Journals (Sweden)

VANDANA NIRANJAN

2017-01-01

Full Text Available In this paper, a new approach to enhance the bandwidth of flipped voltage follower is explored. The proposed approach is based on gate-body driven technique. This technique boosts the transconductance in a MOS transistor as both gate and body/bulk terminals are tied together and used as signal input. This novel technique appears as a good solution to merge the advantages of gate-driven and bulk-driven techniques and suppress their disadvantages. The gate-body driven technique utilizes body effect to enable low voltage low power operation and improves the overall performance of flipped voltage follower, providing it with low output impedance, high input impedance and bandwidth extension ratio of 2.614. The most attractive feature is that bandwidth enhancement has been achieved without use of any passive component or extra circuitry. Simulations in PSpice environment for 180 nm CMOS technology verified the predicted theoretical results. The improved flipped voltage follower is particularly interesting for high frequency low noise signal processing applications.

Wireless data transmission for high energy physics applications

Science.gov (United States)

Dittmeier, Sebastian; Brenner, Richard; Dancila, Dragos; Dehos, Cedric; De Lurgio, Patrick; Djurcic, Zelimir; Drake, Gary; Gonzalez Gimenez, Jose Luis; Gustafsson, Leif; Kim, Do-Won; Locci, Elizabeth; Pfeiffer, Ullrich; Röhrich, Dieter; Rydberg, Anders; Schöning, André; Siligaris, Alexandre; Soltveit, Hans Kristian; Ullaland, Kjetil; Vincent, Pierre; Rodriguez Vazquez, Pedro; Wiedner, Dirk; Yang, Shiming

2017-08-01

Silicon tracking detectors operated at high luminosity collider experiments pose a challenge for current and future readout systems regarding bandwidth, radiation, space and power constraints. With the latest developments in wireless communications, wireless readout systems might be an attractive alternative to commonly used wired optical and copper based readout architectures. The WADAPT group (Wireless Allowing Data and Power Transmission) has been formed to study the feasibility of wireless data transmission for future tracking detectors. These proceedings cover current developments focused on communication in the 60 GHz band. This frequency band offers a high bandwidth, a small form factor and an already mature technology. Motivation for wireless data transmission for high energy physics application and the developments towards a demonstrator prototype are summarized. Feasibility studies concerning the construction and operation of a wireless transceiver system have been performed. Data transmission tests with a transceiver prototype operating at even higher frequencies in the 240 GHz band are described. Data transmission at rates up to 10 Gb/s have been obtained successfully using binary phase shift keying.

Fully integrated CMOS pixel detector for high energy particles

International Nuclear Information System (INIS)

Vanstraelen, G.; Debusschere, I.; Claeys, C.; Declerck, G.

1989-01-01

A novel type of position and energy sensitive, monolithic pixel array with integrated readout electronics is proposed. Special features of the design are a reduction of the number of output channels and of the amount of output data, and the use of transistors on the high resistivity silicon. The number of output channels for the detector array is reduced by handling in parallel a number of pixels, chosen as a function of the time resolution required for the system, and by the use of an address decoder. A further reduction of data is achieved by reading out only those pixels which have been activated. The pixel detector circuit will be realized in a 3 μm p-well CMOS process, which is optimized for the full integration of readout electronics and detector diodes on high resistivity Si. A retrograde well is formed by means of a high energy implantation, followed by the appropriate temperature steps. The optimization of the well shape takes into account the high substrate bias applied during the detector operation. The design is largely based on the use of MOS transistors on the high resistivity silicon itself. These have proven to perform as well as transistors on standard doped substrate. The basic building elements as well as the design strategy of the integrated pixel detector are presented in detail. (orig.)

Kernel-based noise filtering of neutron detector signals

International Nuclear Information System (INIS)

Park, Moon Ghu; Shin, Ho Cheol; Lee, Eun Ki

2007-01-01

This paper describes recently developed techniques for effective filtering of neutron detector signal noise. In this paper, three kinds of noise filters are proposed and their performance is demonstrated for the estimation of reactivity. The tested filters are based on the unilateral kernel filter, unilateral kernel filter with adaptive bandwidth and bilateral filter to show their effectiveness in edge preservation. Filtering performance is compared with conventional low-pass and wavelet filters. The bilateral filter shows a remarkable improvement compared with unilateral kernel and wavelet filters. The effectiveness and simplicity of the unilateral kernel filter with adaptive bandwidth is also demonstrated by applying it to the reactivity measurement performed during reactor start-up physics tests

A high-throughput, multi-channel photon-counting detector with picosecond timing

Science.gov (United States)

Lapington, J. S.; Fraser, G. W.; Miller, G. M.; Ashton, T. J. R.; Jarron, P.; Despeisse, M.; Powolny, F.; Howorth, J.; Milnes, J.

2009-06-01

High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchannel plate devices with very high time resolution, and high-speed multi-channel ASIC electronics developed for the LHC at CERN, provides the necessary building blocks for a high-throughput detector system with up to 1024 parallel counting channels and 20 ps time resolution. We describe the detector and electronic design, discuss the current status of the HiContent project and present the results from a 64-channel prototype system. In the absence of an operational detector, we present measurements of the electronics performance using a pulse generator to simulate detector events. Event timing results from the NINO high-speed front-end ASIC captured using a fast digital oscilloscope are compared with data taken with the proposed electronic configuration which uses the multi-channel HPTDC timing ASIC.

A high-throughput, multi-channel photon-counting detector with picosecond timing

International Nuclear Information System (INIS)

Lapington, J.S.; Fraser, G.W.; Miller, G.M.; Ashton, T.J.R.; Jarron, P.; Despeisse, M.; Powolny, F.; Howorth, J.; Milnes, J.

2009-01-01

High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchannel plate devices with very high time resolution, and high-speed multi-channel ASIC electronics developed for the LHC at CERN, provides the necessary building blocks for a high-throughput detector system with up to 1024 parallel counting channels and 20 ps time resolution. We describe the detector and electronic design, discuss the current status of the HiContent project and present the results from a 64-channel prototype system. In the absence of an operational detector, we present measurements of the electronics performance using a pulse generator to simulate detector events. Event timing results from the NINO high-speed front-end ASIC captured using a fast digital oscilloscope are compared with data taken with the proposed electronic configuration which uses the multi-channel HPTDC timing ASIC.

Bandwidth Assessment for MultiRotor UAVs

Directory of Open Access Journals (Sweden)

Ferrarese Gastone

2017-06-01

Full Text Available This paper is a technical note about the theoretical evaluation of the bandwidth of multirotor helicopters. Starting from a mathematical linear model of the dynamics of a multirotor aircraft, the transfer functions of the state variables that deeply affect the stability characteristics of the aircraft are obtained. From these transfer functions, the frequency response analysis of the system is effected. After this analysis, the bandwidth of the system is defined. This result is immediately utilized for the design of discrete PID controllers for hovering flight stabilization. Numeric simulations are shown to demonstrate that the knowledge of the bandwidth is a valid aid in the design of flight control systems of these machines.

Negative optical inertia for enhancing the sensitivity of future gravitational-wave detectors

International Nuclear Information System (INIS)

Khalili, Farid; Danilishin, Stefan; Mueller-Ebhardt, Helge; Miao Haixing; Zhao Chunnong; Chen Yanbei

2011-01-01

We consider enhancing the sensitivity of future gravitational-wave detectors by using double optical spring. When the power, detuning and bandwidth of the two carriers are chosen appropriately, the effect of the double optical spring can be described as a 'negative inertia', which cancels the positive inertia of the test masses and thus increases their response to gravitational waves. This allows us to surpass the free-mass standard quantum limit (SQL) over a broad frequency band, through signal amplification, rather than noise cancellation, which has been the case for all broadband SQL-beating schemes so far considered for gravitational-wave detectors. The merit of such signal amplification schemes lies in the fact that they are less susceptible to optical losses than noise-cancellation schemes. We show that it is feasible to demonstrate such an effect with the Gingin High Optical Power Test Facility, and it can eventually be implemented in future advanced GW detectors.

High precision detector robot arm system

Science.gov (United States)

Shu, Deming; Chu, Yong

2017-01-31

A method and high precision robot arm system are provided, for example, for X-ray nanodiffraction with an X-ray nanoprobe. The robot arm system includes duo-vertical-stages and a kinematic linkage system. A two-dimensional (2D) vertical plane ultra-precision robot arm supporting an X-ray detector provides positioning and manipulating of the X-ray detector. A vertical support for the 2D vertical plane robot arm includes spaced apart rails respectively engaging a first bearing structure and a second bearing structure carried by the 2D vertical plane robot arm.

Comparison of charge collection in semiconductor detectors and timing resolution, using a sub-nanosecond transimpedance amplifier

International Nuclear Information System (INIS)

Rudge, A.

1995-01-01

A transimpedance amplifier, with a risetime of <600 ps and a noise of <1000 RMS electrons in a 500 MHz bandwidth, has been used for comparison of charge collection times in silicon, gallium arsenide and diamond detectors. The use of silicon detectors as trigger counters/hodoscopes is demonstrated, together with measured timing characteristics. (orig.)

Comparison of charge collection in semiconductor detectors and timing resolution, using a sub-nanosecond transimpedance amplifier

Energy Technology Data Exchange (ETDEWEB)

Rudge, A. [European Organization for Nuclear Research, Geneva (Switzerland)

1995-06-01

A transimpedance amplifier, with a risetime of <600 ps and a noise of <1000 RMS electrons in a 500 MHz bandwidth, has been used for comparison of charge collection times in silicon, gallium arsenide and diamond detectors. The use of silicon detectors as trigger counters/hodoscopes is demonstrated, together with measured timing characteristics. (orig.).

High-Rate Performance of Muon Drift Tube Detectors

CERN Document Server

Schwegler, Philipp

The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are stud...

Gain-switched, Yb-doped, all-fiber laser with narrow bandwidth

DEFF Research Database (Denmark)

Larsen, Casper; Giesberts, Martin; Nyga, Sebastian

2013-01-01

We demonstrate that an all-fiber, narrow bandwidth, high pulse energy pulsed laser can be constructed from commercially available components by applying gain-switching. After single-stage amplification the pulses are frequency doubled in ppSLT with high efficiency....

Adaptive slope compensation for high bandwidth digital current mode controller

DEFF Research Database (Denmark)

Taeed, Fazel; Nymand, Morten

2015-01-01

An adaptive slope compensation method for digital current mode control of dc-dc converters is proposed in this paper. The compensation slope is used for stabilizing the inner current loop in peak current mode control. In this method, the compensation slope is adapted with the variations...... in converter duty cycle. The adaptive slope compensation provides optimum controller operation in term of bandwidth over wide range of operating points. In this paper operation principle of the controller is discussed. The proposed controller is implemented in an FPGA to control a 100 W buck converter...

Impact of crystal orientation on the modulation bandwidth of InGaN/GaN light-emitting diodes

Science.gov (United States)

Monavarian, M.; Rashidi, A.; Aragon, A. A.; Oh, S. H.; Rishinaramangalam, A. K.; DenBaars, S. P.; Feezell, D.

2018-01-01

High-speed InGaN/GaN blue light-emitting diodes (LEDs) are needed for future gigabit-per-second visible-light communication systems. Large LED modulation bandwidths are typically achieved at high current densities, with reports close to 1 GHz bandwidth at current densities ranging from 5 to 10 kA/cm2. However, the internal quantum efficiency (IQE) of InGaN/GaN LEDs is quite low at high current densities due to the well-known efficiency droop phenomenon. Here, we show experimentally that nonpolar and semipolar orientations of GaN enable higher modulation bandwidths at low current densities where the IQE is expected to be higher and power dissipation is lower. We experimentally compare the modulation bandwidth vs. current density for LEDs on nonpolar (10 1 ¯ 0 ), semipolar (20 2 ¯ 1 ¯) , and polar (" separators="|0001 ) orientations. In agreement with wavefunction overlap considerations, the experimental results indicate a higher modulation bandwidth for the nonpolar and semipolar LEDs, especially at relatively low current densities. At 500 A/cm2, the nonpolar LED has a 3 dB bandwidth of ˜1 GHz, while the semipolar and polar LEDs exhibit bandwidths of 260 MHz and 75 MHz, respectively. A lower carrier density for a given current density is extracted from the RF measurements for the nonpolar and semipolar LEDs, consistent with the higher wavefunction overlaps in these orientations. At large current densities, the bandwidth of the polar LED approaches that of the nonpolar and semipolar LEDs due to coulomb screening of the polarization field. The results support using nonpolar and semipolar orientations to achieve high-speed LEDs at low current densities.

Compton imaging with a highly-segmented, position-sensitive HPGe detector

Energy Technology Data Exchange (ETDEWEB)

Steinbach, T.; Hirsch, R.; Reiter, P.; Birkenbach, B.; Bruyneel, B.; Eberth, J.; Hess, H.; Lewandowski, L. [Universitaet zu Koeln, Institut fuer Kernphysik, Koeln (Germany); Gernhaeuser, R.; Maier, L.; Schlarb, M.; Weiler, B.; Winkel, M. [Technische Universitaet Muenchen, Physik Department, Garching (Germany)

2017-02-15

A Compton camera based on a highly-segmented high-purity germanium (HPGe) detector and a double-sided silicon-strip detector (DSSD) was developed, tested, and put into operation; the origin of γ radiation was determined successfully. The Compton camera is operated in two different modes. Coincidences from Compton-scattered γ-ray events between DSSD and HPGe detector allow for best angular resolution; while the high-efficiency mode takes advantage of the position sensitivity of the highly-segmented HPGe detector. In this mode the setup is sensitive to the whole 4π solid angle. The interaction-point positions in the 36-fold segmented large-volume HPGe detector are determined by pulse-shape analysis (PSA) of all HPGe detector signals. Imaging algorithms were developed for each mode and successfully implemented. The angular resolution sensitively depends on parameters such as geometry, selected multiplicity and interaction-point distances. Best results were obtained taking into account the crosstalk properties, the time alignment of the signals and the distance metric for the PSA for both operation modes. An angular resolution between 13.8 {sup circle} and 19.1 {sup circle}, depending on the minimal interaction-point distance for the high-efficiency mode at an energy of 1275 keV, was achieved. In the coincidence mode, an increased angular resolution of 4.6 {sup circle} was determined for the same γ-ray energy. (orig.)

Bandwidth Impacts of Localizing Peer-to-Peer IP Video Traffic in Access and Aggregation Networks

Directory of Open Access Journals (Sweden)

Kenneth Kerpez

2008-10-01

Full Text Available This paper examines the burgeoning impact of peer-to-peer (P2P traffic IP video traffic. High-quality IPTV or Internet TV has high-bandwidth requirements, and P2P IP video could severely strain broadband networks. A model for the popularity of video titles is given, showing that some titles are very popular and will often be available locally; making localized P2P attractive for video titles. The bandwidth impacts of localizing P2P video to try and keep traffic within a broadband access network area or within a broadband access aggregation network area are examined. Results indicate that such highly localized P2P video can greatly lower core bandwidth usage.

Detector Developments for the High Luminosity LHC Era (1/4)

CERN Multimedia

CERN. Geneva

2010-01-01

Calorimetry and Muon Spectrometers - Part I : In the first part of the lecture series, the motivation for a high luminosity upgrade of the LHC will be quickly reviewed together with the challenges for the LHC detectors. In particular, the plans and ongoing research for new calorimeter detectors will be explained. The main issues in the high-luminosity era are an improved radiation tolerance, natural ageing of detector components and challenging trigger and physics requirements. The new technological solutions for calorimetry at a high-luminosity LHC will be reviewed.

High-Rate Glass Resistive Plate Chambers For LHC Muon Detectors Upgrade

CERN Document Server

Laktineh, I; Cauwenbergh, S; Combret, C; Crotty, I; Haddad, Y; Grenier, G; Guida, R; Kieffer, R; Lumb, N; Mirabito, L; Schirra, F; Seguin, N; Tytgat, M; Van der Donckt, M; Wang, Y; Zaganidis, N

2012-01-01

The limitation of the detection rate of standard bakelite resistive plate chambers (RPC) used as muon detector in LHC experiments is behind the absence of such detectors in the high TJ regions in both CMS and ATLAS detectors. RPCs made with low resistivity glass plates (10ID O.cm) could be an adequate solution to equip the high TJ regions extending thus both the trigger efficiency and the physics performance. Different beam tests with single and multi-gap configurations using the new glass have shown that such detectors can operate at few thousands Hzlcm2 with high efficiency( > 90%).

High resolution, position sensitive detector for energetic particle beams

International Nuclear Information System (INIS)

Marsh, E.P.; Strathman, M.D.; Reed, D.A.; Odom, R.W.; Morse, D.H.; Pontau, A.E.

1993-01-01

The performance and design of an imaging position sensitive, particle beam detector will be presented. The detector is minimally invasive, operates a wide dynamic range (>10 10 ), and exhibits high spatial resolution. The secondary electrons produced when a particle beam passes through a thin foil are imaged using stigmatic ion optics onto a two-dimensional imaging detector. Due to the low scattering cross section of the 6 nm carbon foil the detector is a minimal perturbation on the primary beam. A prototype detector with an image resolution of approximately 5 μm for a field of view of 1 mm has been reported. A higher resolution detector for imaging small beams (<50 μm) with an image resolution of better than 0.5 μm has since been developed and its design is presented. (orig.)

Operational Experience and Performance with the ATLAS Pixel detector

CERN Document Server

Yang, Hongtao; The ATLAS collaboration

2018-01-01

In this presentation, I will discuss the operation of ATLAS Pixel Detector during Run 2 proton-proton data-taking at √s=13 TeV in 2017. The topics to be covered include 1) the bandwidth issue and how it is mitigated through readout upgrade and threshold adjustment; 2) the auto-corrective actions; 3) monitoring of radiation effects.

Average Bandwidth Allocation Model of WFQ

Directory of Open Access Journals (Sweden)

Tomáš Balogh

2012-01-01

Full Text Available We present a new iterative method for the calculation of average bandwidth assignment to traffic flows using a WFQ scheduler in IP based NGN networks. The bandwidth assignment calculation is based on the link speed, assigned weights, arrival rate, and average packet length or input rate of the traffic flows. We prove the model outcome with examples and simulation results using NS2 simulator.

High pressure argon detector of high energy neutrinos

International Nuclear Information System (INIS)

Vishnevskii, A.V.; Golutvin, I.A.; Sarantsev, V.L.; Sviridov, V.A.; Dolgoshein, B.A.; Kalinovskii, A.N.; Sosnovtsev, V.V.; Chernyatin, V.K.; Kaftanov, V.S.; Khovanskii, V.D.; Shevchenko, V.G.

1979-01-01

In the present paper, we suggest an electron neutrino detector of a new type where track information is available for all charged particles. As a working medium we use Argon compressed up to a pressure of 100 to 150 atm (approximately 0.2-0.3 g/cm 3 ). The spatial reconstruction of tracks are accomplished with an accuracy not inferior to that of bubble chambers. The detector has a high sensitivity in ionization measurements. An assembly with a working medium mass of approximately 100 tons seem to be realisable. This makes it possible to perform tasks with cross-sections of (10 -5 + 10 -3 ) x delty tot at an intensity of the neutrino beam which is available in present-day accelerators. (orig.)

Digital signal processors for cryogenic high-resolution x-ray detector readout

International Nuclear Information System (INIS)

Friedrich, Stephan; Drury, Owen B.; Bechstein, Sylke; Hennig, Wolfgang; Momayezi, Michael

2003-01-01

We are developing fast digital signal processors (DSPs) to read out superconducting high-resolution X-ray detectors with on-line pulse processing. For superconducting tunnel junction (STJ) detector read-out, the DSPs offer online filtering, rise time discrimination and pile-up rejection. Compared to analog pulse processing, DSP readout somewhat degrades the detector resolution, but improves the spectral purity of the detector response. We discuss DSP performance with our 9-channel STJ array for synchrotron-based high-resolution X-ray spectroscopy. (author)

Results from the AMANDA high-energy neutrino detector

International Nuclear Information System (INIS)

Biron, A.

2001-01-01

This paper briefly summarizes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector. The complete data set from 1997 was analyzed. For E μ > 10 TeV, the detector exceeds 10,000 m 2 in effective area between declinations of 25 and 90 degrees. Neutrinos generated in the atmosphere by cosmic ray interactions were used to verify the overall sensitivity of the coincident events between the SPASE air shower array and the AMANDA detector. Preliminary flux limits from point source candidates are presented. For declinations larger than +45 degrees, our results compare favourably to existing limits for sources in the Southern sky. We also present the current status of the searches for high-energy neutrino emission from diffusely distributed sources, GRBs, and WIMPs from the center of the Earth

Energy efficiency in elastic-bandwidth optical networks

DEFF Research Database (Denmark)

Vizcaino, Jorge Lopez; Ye, Yabin; Tafur Monroy, Idelfonso

2011-01-01

of elastic bandwidth allocation, opens new horizons in the operation of optical networks. In this paper, we compare the network planning problem in an elastic bandwidth CO-OFDM-based network and a fixed-grid WDM network. We highlight the benefits that bandwidth elasticity and the selection of different......The forecasted growth in the Internet traffic has made the operators and industry to be concerned about the power consumption of the networks, and to become interested in alternatives to plan and operate the networks in a more energy efficient manner. The introduction of OFDM, and its property...

Physics potential of ATLAS detector with high luminosity

International Nuclear Information System (INIS)

Zhou, Bing

2004-01-01

The ATLAS detector is designed to exploit the full physics potential in the TeV energy region opened up by the Large Hadron Collider at a center of mass energy of 14 TeV with very high luminosities. The physics performance of the ATLAS detector on Higgs, extra-dimension and strong symmetry breaking scenario is summarized in this note. ATLAS experiment has great discovery potential for these new phenomena with high luminosity. Triple gauge couplings are very sensitive for probing new physics at TeV scale. We show that ATLAS can measure these couplings very precisely with high luminosity. (orig.)

FELIX: the new detector interface for the ATLAS experiment

CERN Document Server

Wu, Weihao; The ATLAS collaboration

2018-01-01

During the next major shutdown (2019-2020), the ATLAS experiment at the LHC at CERN will adopt the Front-End Link eXchange (FELIX) system as the interface between the data acquisition, detector control and TTC (Timing, Trigger and Control) systems and new or updated trigger and detector front-end electronics. FELIX will function as a router between custom serial links from front-end ASICs and FPGAs to data collection and processing components via a commodity switched network. Links may aggregate many slower links or be a single high bandwidth link. FELIX will also forward the LHC bunch-crossing clock, fixed latency trigger accepts and resets received from the TTC system to front-end electronics. The FELIX system uses commodity server technology in combination with FPGA-based PCIe I/O cards. The FELIX servers will run a software routing platform serving data to network clients. Commodity servers connected to FELIX systems via the same network will run the new Software Readout Driver (SW ROD) infrastructure for...

FELIX: the New Detector Interface for the ATLAS Experiment

CERN Document Server

Aggarwal, Anamika; The ATLAS collaboration

2018-01-01

During the next major shutdown (2019-2020), the ATLAS experiment at the LHC will adopt the Front-End Link eXchange (FELIX) system as the interface between the data acquisition, detector control and TTC (Timing, Trigger and Control) systems and new or updated trigger and detector front-end electronics. FELIX will function as a router between custom serial links from front-end ASICs and FPGAs to data collection and processing components via a commodity switched network. Links may aggregate many slower links or be a single high bandwidth link. FELIX will also forward the LHC bunch-crossing clock, fixed latency trigger accepts and resets received from the TTC system to front-end electronics. The FELIX system uses commodity server technology in combination with FPGA-based PCIe I/O cards. The FELIX servers will run a software routing platform serving data to network clients. Commodity servers connected to FELIX systems via the same network will run the new Software Readout Driver (SW ROD) infrastructure for event f...

Orion, a high efficiency 4π neutron detector

International Nuclear Information System (INIS)

Crema, E.; Piasecki, E.; Wang, X.M.; Doubre, H.; Galin, J.; Guerreau, D.; Pouthas, J.; Saint-Laurent, F.

1990-01-01

In intermediate energy heavy ion collisions the multiplicity of emitted neutrons is strongly connected to energy dissipation and to impact parameter. We present the 4π detector ORION, a high efficiency liquid scintillator detector which permits to get information on the multiplicity of neutrons measured event-wise and on the spatial distribution of these neutrons [fr

Bandwidth Impacts of Localizing Peer-to-Peer IP Video Traffic in Access and Aggregation Networks

Directory of Open Access Journals (Sweden)

Kerpez Kenneth

2008-01-01

Full Text Available Abstract This paper examines the burgeoning impact of peer-to-peer (P2P traffic IP video traffic. High-quality IPTV or Internet TV has high-bandwidth requirements, and P2P IP video could severely strain broadband networks. A model for the popularity of video titles is given, showing that some titles are very popular and will often be available locally; making localized P2P attractive for video titles. The bandwidth impacts of localizing P2P video to try and keep traffic within a broadband access network area or within a broadband access aggregation network area are examined. Results indicate that such highly localized P2P video can greatly lower core bandwidth usage.

Prototype of high resolution PET using resistive electrode position sensitive CdTe detectors

International Nuclear Information System (INIS)

Kikuchi, Yohei; Ishii, Keizo; Matsuyama, Shigeo; Yamazaki, Hiromichi

2008-01-01

Downsizing detector elements makes it possible that spatial resolutions of positron emission tomography (PET) cameras are improved very much. From this point of view, semiconductor detectors are preferable. To obtain high resolution, the pixel type or the multi strip type of semiconductor detectors can be used. However, in this case, there is a low packing ratio problem, because a dead area between detector arrays cannot be neglected. Here, we propose the use of position sensitive semiconductor detectors with resistive electrode. The CdTe detector is promising as a detector for PET camera because of its high sensitivity. In this paper, we report development of prototype of high resolution PET using resistive electrode position sensitive CdTe detectors. We made 1-dimensional position sensitive CdTe detectors experimentally by changing the electrode thickness. We obtained 750 A as an appropriate thickness of position sensitive detectors, and evaluated the performance of the detector using a collimated 241 Am source. A good position resolution of 1.2 mm full width half maximum (FWHM) was obtained. On the basis of the fundamental development of resistive electrode position sensitive detectors, we constructed a prototype of high resolution PET which was a dual head type and was consisted of thirty-two 1-dimensional position sensitive detectors. In conclusion, we obtained high resolutions which are 0.75 mm (FWHM) in transaxial, and 1.5 mm (FWHM) in axial. (author)

Development of bonded semiconductor device for high counting rate high efficiency photon detectors

International Nuclear Information System (INIS)

Kanno, Ikuo

2008-01-01

We are trying to decrease dose exposure in medical diagnosis by way of measuring the energy of X-rays. For this purpose, radiation detectors for X-ray energy measurement with high counting rate should be developed. Direct bonding of Si wafers was carried out to make a radiation detector, which had separated X-ray absorber and detector. The resistivity of bonding interface was estimated with the results of four-probe measurements and model calculations. Direct bonding of high resistivity p and n-Si wafers was also performed. The resistance of the pn bonded diode was 0.7 MΩ. The resistance should be increased in the future. (author)

A 750MHz and a 8GHz High Bandwidth Digital FFT Spectrometer, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The scope of this project is to to develop a wide bandwidth, low power, and compact single board digital Fast Fourier Transform spectrometer (FFTS) optimized for the...

On semidefinite programming bounds for graph bandwidth

NARCIS (Netherlands)

de Klerk, E.; Nagy, M.; Sotirov, R.

2013-01-01

In this paper, we propose two new lower bounds on graph bandwidth and cyclic bandwidth based on semidefinite programming (SDP) relaxations of the quadratic assignment problem. We compare the new bounds with two other SDP bounds reported in [A. Blum, G. Konjevod, R. Ravi, and S. Vempala,

47 CFR 74.535 - Emission and bandwidth.

Science.gov (United States)

2010-10-01

... digital modulation in paragraph (a) of this section, the resolution bandwidth (BRES) of the measuring...), adjusted upward to the nearest greater resolution bandwidth available on the measuring equipment. In all... frequency energy outside the assigned channel. Upon notice by the FCC to the station licensee that...

A noise model for the Brazilian gravitational wave detector 'Mario Schenberg'

International Nuclear Information System (INIS)

Frajuca, Carlos; Ribeiro, Kilder L; Andrade, Luiz A; Aguiar, Odylio D; Magalhaes, Nadja S; Jr, Rubens de Melo Marinho

2004-01-01

'Mario Schenberg' is a spherical resonant-mass gravitational wave (GW) detector that will be part of a GW detection array of three detectors. The other two will be built in Italy and in The Netherlands. Their resonant frequencies will be around 3.2 kHz with a bandwidth of about 200 Hz. This range of frequencies is new in a field where the typical frequencies lay below 1 kHz, making the development of the mechanical system much more complex. In this work, a noise model of the detector is presented, where all main sources of noise were taken into account. The final goal is to calculate the expected sensitivity of the detector, analysing which parameters must be changed to improve this

High-Power and High-Efficiency 1.3- µm Superluminescent Diode With Flat-Top and Ultrawide Emission Bandwidth

KAUST Repository

Khan, Mohammed Zahed Mustafa; Alhashim, Hala H.; Ng, Tien Khee; Ooi, Boon S.

2015-01-01

We report on a flat-top and ultrawide emission bandwidth of 125 nm from InGaAsP/InP multiple quantum-well (MQW) superluminescent diode with antireflection coated and tilted ridge-waveguide device configuration. A total output power in excess of 70 mW with an average power spectral density of 0.56 mW/nm and spectral ripple ≤ 1.2 ± 0.5 dB is measured from the device. Wall-plug efficiency and output power as high as 14% and 80 mW, respectively, is demonstrated from this batch of devices. We attribute the broad emission to the inherent inhomogeneity of the electron-heavy-hole (e-hh) and electron-light-hole (e-lh) recombination of the ground state and the first excited state of the MQWs and their simultaneous emission.

High-Power and High-Efficiency 1.3- µm Superluminescent Diode With Flat-Top and Ultrawide Emission Bandwidth

KAUST Repository

Khan, Mohammed Zahed Mustafa

2015-02-01

We report on a flat-top and ultrawide emission bandwidth of 125 nm from InGaAsP/InP multiple quantum-well (MQW) superluminescent diode with antireflection coated and tilted ridge-waveguide device configuration. A total output power in excess of 70 mW with an average power spectral density of 0.56 mW/nm and spectral ripple ≤ 1.2 ± 0.5 dB is measured from the device. Wall-plug efficiency and output power as high as 14% and 80 mW, respectively, is demonstrated from this batch of devices. We attribute the broad emission to the inherent inhomogeneity of the electron-heavy-hole (e-hh) and electron-light-hole (e-lh) recombination of the ground state and the first excited state of the MQWs and their simultaneous emission.

Experiences in Traceroute and Bandwidth Change Analysis

Energy Technology Data Exchange (ETDEWEB)

Logg, C

2004-06-23

SLAC has been studying end-to-end WAN bandwidth availability and achievability for 2.5 years via IEPM-BW [1]. IEPM-BW performs network intensive tests every 90 minutes. Based on that experience we have also developed a light weight available bandwidth (ABwE [2]) measurement tool that can make a measurement within a second. We are now extending this to a WAN measurement and detection system (IEPM-LITE) aimed at more quickly detecting and troubleshooting network performance problems and also to be more friendly on lower performance paths. IEPM-LITE uses ping, forward traceroutes, and ABwE sensors to monitor, in close to real-time, Round Trip Times (RTT), changes in available bandwidth and routes to and from target hosts. This paper discusses the experiences, techniques and algorithms used to detect and report on significant traceroute and bandwidth changes. The ultimate aim is to develop a lightweight WAN network performance monitoring system that can detect, in near real time, significant changes and generate alerts.

Experiences in Traceroute and Bandwidth Change Analysis

International Nuclear Information System (INIS)

Logg, C

2004-01-01

SLAC has been studying end-to-end WAN bandwidth availability and achievability for 2.5 years via IEPM-BW [1]. IEPM-BW performs network intensive tests every 90 minutes. Based on that experience we have also developed a light weight available bandwidth (ABwE [2]) measurement tool that can make a measurement within a second. We are now extending this to a WAN measurement and detection system (IEPM-LITE) aimed at more quickly detecting and troubleshooting network performance problems and also to be more friendly on lower performance paths. IEPM-LITE uses ping, forward traceroutes, and ABwE sensors to monitor, in close to real-time, Round Trip Times (RTT), changes in available bandwidth and routes to and from target hosts. This paper discusses the experiences, techniques and algorithms used to detect and report on significant traceroute and bandwidth changes. The ultimate aim is to develop a lightweight WAN network performance monitoring system that can detect, in near real time, significant changes and generate alerts

Preamplifier design with wide bandwidth using InGaP/GaAs HBT for 10-Gbps photoreceiver module

International Nuclear Information System (INIS)

Hong, S. E.; Lim, J. M.; Kim, S. I.; Nam, E. S.

2004-01-01

We report a preamplifier with wide bandwidth using high-speed and reliable InGaP/GaAs HBT applicable for 10-Gbps photoreceiver modules. The three-stage preamplifier with a negative feedback resistor demonstrates an effective transimpedance gain of 43 dBΩ, a -3-dB bandwidth of 14 GHz corresponding to a very high transimpedance-bandwidth product of 2.52 THzΩ, and an output return loss of -18 dB up to -3-dB bandwidth. This compact circuit is fabricated with an area of 800 X 700 μm 2 . A photoreceiver module of surface-mountable package type, that is composed of preamplifier and photodiode of surface-illumination type, demonstrates an optical bandwidth of 7.5 GHz at λ = 1.55 μ m and a 45-psec rise/fall time for 10-Gbps. The module shows higher sensitivity for a 10-Gbps optical transmission system.

High resolution, position sensitive detector for energetic particle beams

Energy Technology Data Exchange (ETDEWEB)

Marsh, E P [Charles Evans and Associates, Redwood City, CA (United States); Strathman, M D [Charles Evans and Associates, Redwood City, CA (United States); Reed, D A [Charles Evans and Associates, Redwood City, CA (United States); Odom, R W [Charles Evans and Associates, Redwood City, CA (United States); Morse, D H [Sandia National Labs., Livermore, CA (United States); Pontau, A E [Sandia National Labs., Livermore, CA (United States)

1993-05-01

The performance and design of an imaging position sensitive, particle beam detector will be presented. The detector is minimally invasive, operates a wide dynamic range (>10[sup 10]), and exhibits high spatial resolution. The secondary electrons produced when a particle beam passes through a thin foil are imaged using stigmatic ion optics onto a two-dimensional imaging detector. Due to the low scattering cross section of the 6 nm carbon foil the detector is a minimal perturbation on the primary beam. A prototype detector with an image resolution of approximately 5 [mu]m for a field of view of 1 mm has been reported. A higher resolution detector for imaging small beams (<50 [mu]m) with an image resolution of better than 0.5 [mu]m has since been developed and its design is presented. (orig.)

Signal enhancement by spectral equalization of high frequency broadband signals transmitted through optical fibers

International Nuclear Information System (INIS)

Lyons, P.B.; Ogle, J.W.; Holzman, M.A.

1980-01-01

A new technique is discussed for enhancing the bandwidth and intensity of high frequency (> 1 GHz) analog, spectrally broad (40 nm) signals transmitted through one kilometer of optical fiber. The existing method for bandwidth enhancement of such a signal uses a very narrow (approx. 1 nm) filter between the fiber and detector to limit bandwidth degradation due to material dispersion. Using this method, most of the available optical intensity is rejected and lost. This new technique replaces the narrow-band filter with a spectral equalizer device which uses a reflection grating to disperse the input signal spectrum and direct it onto a linear array of fibers

Efficient Bandwidth Management for Ethernet Passive Optical Networks

KAUST Repository

Elrasad, Amr

2016-01-01

The increasing bandwidth demands in access networks motivates network operators, networking devices manufacturers, and standardization institutions to search for new approaches for access networks. These approaches should support higher bandwidth

Application of cadmium telluride detectors to high energy computed tomography

International Nuclear Information System (INIS)

Glasser, F.; Thomas, G.; Cuzin, M.; Verger, L.

1991-01-01

15 years ago, Cadmium Telluride detectors have been investigated in our laboratory as possible detectors for medical scanners [1]. Today most of these machines are using high pressure Xenon gas as multicells detectors, BGO or CdWO 4 scintillators for industrial computerized tomography. Xenon gas detectors are well suited for detection of 100 KeV X-rays and enables to build 1000 cells homogeneous detector with a dynamic range of 3 decades. BGO and CdWO 4 scintillators, associated with photomultipliers or photodiodes are used for higher energy (400 KeV). They present a low afterglow and a dynamic range of 4 to 5 decades. Non destructive testing of very absorbing objects (eg 2 m diameter solid rocket motor) by X-ray tomography requires much higher energy X-rays (16 MeV) and doses up to 12000 rads/min at 1 meter. For this application Cadmium Telluride detectors operating as photoconductors are well suited. A prototype of tomograph machine, able to scan 0.5 m diameter high density objects has been realized with 25 CdTe detectors (25x15x0.8 mm 3 ). It produces good quality 1024x1024 tomographic images

Test Beam Performance Measurements for the Phase I Upgrade of the CMS Pixel Detector

CERN Document Server

Dragicevic, M.; Hrubec, J.; Steininger, H.; Gädda, A.; Härkönen, J.; Lampén, T.; Luukka, P.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Winkler, A.; Eerola, P.; Tuuva, T.; Baulieu, G.; Boudoul, G.; Caponetto, L.; Combaret, C.; Contardo, D.; Dupasquier, T.; Gallbit, G.; Lumb, N.; Mirabito, L.; Perries, S.; Donckt, M.Vander; Viret, S.; Bonnin, C.; Charles, L.; Gross, L.; Hosselet, J.; Tromson, D.; Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Pierschel, G.; Preuten, M.; Rauch, M.; Wlochal, M.; Aldaya, M.; Asawatangtrakuldee, C.; Beernaert, K.; Bertsche, D.; Contreras-Campana, C.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Gallo, E.; Garcia, J.Garay; Hansen, K.; Haranko, M.; Harb, A.; Hauk, J.; Keaveney, J.; Kalogeropoulos, A.; Kleinwort, C.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Pitzl, D.; Reichelt, O.; Savitskyi, M.; Schütze, P.; Sola, V.; Spannagel, S.; Walsh, R.; Zuber, A.; Biskop, H.; Buhmann, P.; Centis-Vignali, M.; Garutti, E.; Haller, J.; Hoffmann, M.; Klanner, R.; Lapsien, T.; Matysek, M.; Perieanu, A.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schwandt, J.; Sonneveld, J.; Steinbrück, G.; Vormwald, B.; Wellhausen, J.; Abbas, M.; Amstutz, C.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; Boer, W.De; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Freund, B.; Hartmann, F.; Heindl, S.; Husemann, U.; Kornmeyer, A.; Kudella, S.; Muller, Th.; Simonis, H.J.; Steck, P.; Weber, M.; Weiler, Th.; Kiss, T.; Siklér, F.; Tölyhi, T.; Veszprémi, V.; Cariola, P.; Creanza, D.; Palma, M.De; Robertis, G.De; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Costa, S.; Mattia, A.Di; Giordano, F.; Potenza, R.; Saizu, M.A.; Tricomi, A.; Tuve, C.; Focardi, E.; Dinardo, M.E.; Fiorendi, S.; Gennai, S.; Malvezzi, S.; Manzoni, R.A.; Menasce, D.; Moroni, L.; Pedrini, D.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Pozzobon, N.; Tosi, M.; Solestizi, L.Alunni; Biasini, M.; Bilei, G.M.; Cecchi, C.; Checcucci, B.; Ciangottini, D.; Fanò, L.; Gentsos, C.; Ionica, M.; Leonardi, R.; Manoni, E.; Mantovani, G.; Marconi, S.; Mariani, V.; Menichelli, M.; Modak, A.; Morozzi, A.; Moscatelli, F.; Passeri, D.; Placidi, P.; Postolache, V.; Rossi, A.; Saha, A.; Santocchia, A.; Storchi, L.; Spiga, D.; Androsov, K.; Azzurri, P.; Bagliesi, G.; Basti, A.; Boccali, T.; Borrello, L.; Bosi, F.; Castaldi, R.; Ceccanti, M.; Ciocci, M.A.; Dell'Orso, R.; Donato, S.; Fedi, G.; Giassi, A.; Grippo, M.T.; Ligabue, F.; Magazzu, G.; Mammini, P.; Mariani, F.; Mazzoni, E.; Messineo, A.; Moggi, A.; Morsani, F.; Palla, F.; Palmonari, F.; Profeti, A.; Raffaelli, F.; Ragonesi, A.; Rizzi, A.; Soldani, A.; Spagnolo, P.; Tenchini, R.; Tonelli, G.; Venturi, A.; Verdini, P.G.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bonnaud, J.; Daguin, J.; D'Auria, A.; Detraz, S.; Dondelewski, O.; Engegaard, B.; Faccio, F.; Frank, N.; Gill, K.; Honma, A.; Kornmayer, A.; Labaza, A.; Manolescu, F.; McGill, I.; Mersi, S.; Michelis, S.; Onnela, A.; Ostrega, M.; Pavis, S.; Peisert, A.; Pernot, J.F.; Petagna, P.; Postema, H.; Rapacz, K.; Sigaud, C.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Verlaat, B.; Vichoudis, P.; Zwalinski, L.; Bachmair, F.; Becker, R.; di Calafiori, D.; Casal, B.; Berger, P.; Djambazov, L.; Donega, M.; Grab, C.; Hits, D.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Arbol, P.Martinez Ruiz del; Masciovecchio, M.; Meinhard, M.; Perozzi, L.; Roeser, U.; Starodumov, A.; Tavolaro, V.; Wallny, R.; Zhu, D.; Amsler, C.; Bösiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; de Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.H.; Dietz, C.; Fiori, F.; Grundler, U.; Hou, W.S.; Lu, R.S.; Moya, M.; Tsai, J.F.; Tzeng, Y.M.; Cussans, D.; Goldstein, J.; Grimes, M.; Newbold, D.; Hobson, P.; Reid, I.D.; Auzinger, G.; Bainbridge, R.; Dauncey, P.; Hall, G.; James, T.; Magnan, A.M.; Pesaresi, M.; Raymond, D.M.; Uchida, K.; Durkin, T.; Harder, K.; Shepherd-Themistocleous, C.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Olmedo, M.; Si, W.; Yates, B.R.; Dominguez, A.; Bartek, R.; Bentele, B.; Cumalat, J.P.; Ford, W.T.; Jensen, F.; Johnson, A.; Krohn, M.; Leontsinis, S.; Mulholland, T.; Stenson, K.; Wagner, S.R.; Apresyan, A.; Bolla, G.; Burkett, K.; Butler, J.N.; Canepa, A.; Cheung, H.W.K.; Christian, D.; Cooper, W.E.; Deptuch, G.; Derylo, G.; Gingu, C.; Grünendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Kahlid, F.; Kwan, S.; Lei, C.M.; Lipton, R.; Sá, R.Lopes De; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Schneider, B.; Sellberg, G.; Shenai, A.; Siehl, K.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Berry, D.R.; Chen, X.; Ennesser, L.; Evdokimov, A.; Gerber, C.E.; Makauda, S.; Mills, C.; Gonzalez, I.D.Sandoval; Alimena, J.; Antonelli, L.J.; Francis, B.; Hart, A.; Hill, C.S.; Parashar, N.; Stupak, J.; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D.H.; Shi, X.; Baringer, P.; Bean, A.; Khalil, S.; Kropivnitskaya, A.; Majumder, D.; Schmitz, E.; Wilson, G.; Ivanov, A.; Mendis, R.; Mitchell, T.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J.G.; Cremaldi, L.M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Claes, D.R.; Fangmeier, C.; Suarez, R.Gonzalez; Monroy, J.; Siado, J.; Bartz, E.; Gershtein, Y.; Halkiadakis, E.; Kyriacou, S.; Lath, A.; Nash, K.; Osherson, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Norberg, S.; Vargas, J.E.Ramirez; Alyari, M.; Dolen, J.; Godshalk, A.; Harrington, C.; Iashvili, I.; Kharchilava, A.; Nguyen, D.; Parker, A.; Rappoccio, S.; Roozbahani, B.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; McDermott, K.; Mirman, N.; Rinkevicius, A.; Ryd, A.; Salvati, E.; Skinnari, L.; Soffi, L.; Tao, Z.; Thom, J.; Tucker, J.; Zientek, M.; Akgün, B.; Ecklund, K.M.; Kilpatrick, M.; Nussbaum, T.; Zabel, J.; D'Angelo, P.; Johns, W.; Rose, K.

2017-05-30

A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These upgrades allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. In this paper, comprehensive test beam studies are presented which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency has been determined to be ($99.95 \\pm 0.05$) \\%, while the intrinsic spatial resolution has been measured to be ($4.80 \\pm 0.25$) $\\mu$m and ($7.99 \\pm 0.21$...

Chemical Industry Bandwidth Study

Energy Technology Data Exchange (ETDEWEB)

none,

2006-12-01

The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

Full energy peak efficiency of composite detectors for high energy gamma-rays

International Nuclear Information System (INIS)

Kshetri, Ritesh

2015-01-01

Experiments involving radioactive beams demand high detection efficiencies. One of the ways to obtain high detection efficiency without deteriorating the energy resolution or timing characteristics is the use of composite detectors which are composed of standard HPGe crystals arranged in a compact way. Two simplest composite detectors are the clover and cluster detectors. The TRIUMF-ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS) comprises of 16 large volume, 32-fold segmented HPGe clover detectors, where each detector is shielded by a 20-fold segmented escape suppression shield (ESS)

High Resolution PET with 250 micrometer LSO Detectors and Adaptive Zoom

International Nuclear Information System (INIS)

Cherry, Simon R.; Qi, Jinyi

2012-01-01

There have been impressive improvements in the performance of small-animal positron emission tomography (PET) systems since their first development in the mid 1990s, both in terms of spatial resolution and sensitivity, which have directly contributed to the increasing adoption of this technology for a wide range of biomedical applications. Nonetheless, current systems still are largely dominated by the size of the scintillator elements used in the detector. Our research predicts that developing scintillator arrays with an element size of 250 (micro)m or smaller will lead to an image resolution of 500 (micro)m when using 18F- or 64Cu-labeled radiotracers, giving a factor of 4-8 improvement in volumetric resolution over the highest resolution research systems currently in existence. This proposal had two main objectives: (i) To develop and evaluate much higher resolution and efficiency scintillator arrays that can be used in the future as the basis for detectors in a small-animal PET scanner where the spatial resolution is dominated by decay and interaction physics rather than detector size. (ii) To optimize one such high resolution, high sensitivity detector and adaptively integrate it into the existing microPET II small animal PET scanner as a 'zoom-in' detector that provides higher spatial resolution and sensitivity in a limited region close to the detector face. The knowledge gained from this project will provide valuable information for building future PET systems with a complete ring of very high-resolution detector arrays and also lay the foundations for utilizing high-resolution detectors in combination with existing PET systems for localized high-resolution imaging.

Optimal design of similariton fiber lasers without gain-bandwidth limitation.

Science.gov (United States)

Li, Xingliang; Zhang, Shumin; Yang, Zhenjun

2017-07-24

We have numerically investigated broadband high-energy similariton fiber lasers, demonstrated that the self-similar evolution of pulses can locate in a segment of photonic crystal fiber without gain-bandwidth limitation. The effects of various parameters, including the cavity length, the spectral filter bandwidth, the pump power, the length of the photonic crystal fiber and the output coupling ratio have also been studied in detail. Using the optimal parameters, a single pulse with spectral width of 186.6 nm, pulse energy of 23.8 nJ, dechirped pulse duration of 22.5 fs and dechirped pulse peak power of 1.26 MW was obtained. We believe that this detailed analysis of the behaviour of pulses in the similariton regime may have major implications in the development of broadband high-energy fiber lasers.

GEM detector performance with innovative micro-TPC readout in high magnetic field

Directory of Open Access Journals (Sweden)

Garzia I.

2018-01-01

Full Text Available Gas detector development is one of the pillars of the research in fundamental physics. Since several years, a new concept of detectors, called Micro Pattern Gas Detector (MPGD, allowed to overcome several problems related to other types of commonly used detectors, like drift chamber and micro strips detectors, reducing the rate of discharges and providing better radiation tolerance. Among the most used MPGDs are the Gas Electron Multipliers (GEMs. Invented by Sauli in 1997, nowadays GEMs have become an important reality for particle detectors in high energy physics. Commonly deployed as fast timing detectors and triggers, their fast response, high rate capability and high radiation hardness make them also suitable as tracking detectors. The readout scheme is one of the most important features in tracking technology. Analog readout based on the calculation of the center of gravity technique allows to overcome the limit imposed by digital pads, whose spatial resolution is limited by the pitch dimensions. However, the presence of high external magnetic fields can distort the electronic cloud and affect the performance. The development of the micro-TPC reconstruction method brings GEM detectors into a new prospective, improving significantly the spatial resolutionin presence of high magnetic fields. This innovative technique allows to reconstruct the 3-dimensional particle position, as Time Projection Chamber, but within a drift gap of a few millimeters. In these report, the charge centroid and micro-TPC methods are described in details. We discuss the results of several test beams performed with planar chambers in magnetic field. These results are one of the first developments of micro-TPC technique for GEM detectors, which allows to reach unprecedented performance in a high magnetic field of 1 T.

GEM detector performance with innovative micro-TPC readout in high magnetic field

Science.gov (United States)

Garzia, I.; Alexeev, M.; Amoroso, A.; Baldini Ferroli, R.; Bertani, M.; Bettoni, D.; Bianchi, F.; Calcaterra, A.; Canale, N.; Capodiferro, M.; Cassariti, V.; Cerioni, S.; Chai, J. Y.; Chiozzi, S.; Cibinetto, G.; Cossio, F.; Cotta Ramusino, A.; De Mori, F.; Destefanis, M.; Dong, J.; Evangelisti, F.; Evangelisti, F.; Farinelli, R.; Fava, L.; Felici, G.; Fioravanti, E.; Gatta, M.; Greco, M.; Lavezzi, L.; Leng, C. Y.; Li, H.; Maggiora, M.; Malaguti, R.; Marcello, S.; Melchiorri, M.; Mezzadri, G.; Mignone, M.; Morello, G.; Pacetti, S.; Patteri, P.; Pellegrino, J.; Pelosi, A.; Rivetti, A.; Rolo, M. D.; Savrié, M.; Scodeggio, M.; Soldani, E.; Sosio, S.; Spataro, S.; Tskhadadze, E.; Verma, S.; Wheadon, R.; Yan, L.

2018-01-01

Gas detector development is one of the pillars of the research in fundamental physics. Since several years, a new concept of detectors, called Micro Pattern Gas Detector (MPGD), allowed to overcome several problems related to other types of commonly used detectors, like drift chamber and micro strips detectors, reducing the rate of discharges and providing better radiation tolerance. Among the most used MPGDs are the Gas Electron Multipliers (GEMs). Invented by Sauli in 1997, nowadays GEMs have become an important reality for particle detectors in high energy physics. Commonly deployed as fast timing detectors and triggers, their fast response, high rate capability and high radiation hardness make them also suitable as tracking detectors. The readout scheme is one of the most important features in tracking technology. Analog readout based on the calculation of the center of gravity technique allows to overcome the limit imposed by digital pads, whose spatial resolution is limited by the pitch dimensions. However, the presence of high external magnetic fields can distort the electronic cloud and affect the performance. The development of the micro-TPC reconstruction method brings GEM detectors into a new prospective, improving significantly the spatial resolutionin presence of high magnetic fields. This innovative technique allows to reconstruct the 3-dimensional particle position, as Time Projection Chamber, but within a drift gap of a few millimeters. In these report, the charge centroid and micro-TPC methods are described in details. We discuss the results of several test beams performed with planar chambers in magnetic field. These results are one of the first developments of micro-TPC technique for GEM detectors, which allows to reach unprecedented performance in a high magnetic field of 1 T.

A high resolution germanium detector array for hypernuclear studies at PANDA

Energy Technology Data Exchange (ETDEWEB)

Bleser, Sebastian; Sanchez Lorente, Alicia; Steinen, Marcell [Helmholtz-Institut Mainz (Germany); Gerl, Juergen; Kojouharov, Ivan [GSI, Darmstadt (Germany); Iazzi, Felice [Politecnico, Torino, Turin (Italy); INFN, Torino, Turin (Italy); Pochodzalla, Josef; Rittgen, Kai; Sahin, Cihan [Institute for Nuclear Physics, JGU Mainz (Germany); Collaboration: PANDA-Collaboration

2013-07-01

The PANDA experiment, planned at the FAIR facility in Darmstadt, aims at the high resolution γ-spectroscopy of double Λ hypernuclei. For this purpose a devoted detector setup is required, consisting of a primary nuclear target, an active secondary target and a germanium detector array for the γ-spectroscopy. Due to the limited space within the PANDA detector a compact design is required. In particular the conventional LN{sub 2} cooling system must be replaced by an electro-mechanical device and a new arrangement of the crystals is needed. This poster shows the ongoing development of the germanium detectors. Test measurements of a single crystal prototype with an improved cooling concept are shown. Thermal simulations for a triple crystal detector are presented. Aditionally studies of the optimization of the detector arrangement inside the PANDA barrel spectrometer are shown. Finally the status on digital pulse shape analysis is presented which will be necessary to deal with high counting rates and to recover the high original energy resolution in case of neutron damage.

Light box for investigation of characteristics of optoelectronics detectors

Science.gov (United States)

Szreder, Agnieszka; Mazikowski, Adam

2017-09-01

In this paper, a light box for investigation of characteristics of optoelectronic detectors is described. The light box consists of an illumination device, an optical power sensor and a mechanical enclosure. The illumination device is based on four types of high-power light emitting diodes (LED): white light, red, green and blue. The illumination level can be varied for each LED independently by the driver and is measured by optical power sensor. The mechanical enclosure provides stable mounting points for the illumination device, sensor and the examined detector and protects the system from external light, which would otherwise strongly influence the measurement results. Uniformity of illumination distribution provided by the light box for all colors is good, making the measurement results less dependent on the position of the examined detector. The response of optoelectronic detectors can be investigated using the developed light box for each LED separately or for any combination of up to four LED types. As the red, green and blue LEDs are rather narrow bandwidth sources, spectral response of different detectors can be examined for these wavelength ranges. The described light box can be used for different applications. Its primary use is in a student laboratory setup for investigation of characteristics of optoelectronic detectors. Moreover, it can also be used in various colorimetric or photographic applications. Finally, it will be used as a part of demonstrations from the fields of vision and color, performed during science fairs and outreach activities increasing awareness of optics and photonics.

Plasma-focus neutron diagnostics by means of high-sensitivity bubble detectors

International Nuclear Information System (INIS)

Zoita, V.; Pantea, A.; Patran, A.; Lee, P.; Springham, S.V.; Koh, M.; Rawat, R.S.; Zhang, T.; Hassan, M.

2005-01-01

A new type of bubble detector (a superheated fluid detector), the DEFENDER TM , was tested as a neutron diagnostics device on the NX2 plasma focus (PF) device at the NIE/NTU, Singapore. The DEFENDER TM detector was recently developed and commercialised by BTI, Canada, and it is characterised by a very high sensitivity (a factor of about 30 higher than the standard detectors) to fast neutrons (energy above 100 keV). Together with its particular energy response this high sensitivity allows for the development of improved neutron diagnostics for the PF devices. The NX2 plasma focus device has the following typical operating parameters: condenser bank charging voltage: 15 kV; stored energy: 2.3 kJ; peak current: 420 kA; current rise-time: 1.35 μs; deuterium pressure: 20 mbar. During most of the experiments reported here the NX2 device was operated at 14 kV charging voltage and 20 mbar deuterium pressure. A few shots were done at voltages of 14.5 and 15 kV and the same gas pressure. The bubble detector neutron diagnostics experiments carried out on the NX2 machine involved the following measurements: 1. Relative calibration of the four detectors. The detectors were irradiated simultaneously, in identical conditions, by plasma focus neutron pulses and their neutron responses were compared.; 2. angular distribution of the neutron fluence (single shot). The distribution of the neutron fluence was measured at four angles with respect to the PF electrode axis: 0, 30, 60 and 90 deg; 3. Reproducibility of the neutron yield at high repetition rate operation. The NX2 device was operated at 1 Hz repetition rate.; 4. Bubble detector response time. The response time of the DEFENDER TM detector was tested by using the short PF neutron pulses and a high-speed video camera. The paper will present the results of these experiments and their implications for the development of neutron plasma diagnostics techniques based on the bubble detectors and their broader class of superheated

Performance of the CMS Phase 1 Pixel Detector

CERN Document Server

Akgun, Bora

2018-01-01

It is anticipated that the LHC accelerator will reach and exceed the luminosity of L = 2$\\times$10$^{34}$cm$^{-2}$s$^{-1}$ during the LHC Run 2 period until 2023. At this higher luminosity and increased hit occupancies the CMS phase-0 pixel detector would have been subjected to severe dead time and inefficiencies introduced by limited buffers in the analog read-out chip and effects of radiation damage in the sensors. Therefore a new pixel detector has been built and replaced the phase-0 detector in the 2016/17 LHC extended year-end technical stop. The CMS phase-1 pixel detector features four central barrel layers and three end-cap disks in forward and backward direction for robust tracking performance, and a significantly reduced overall material budget including new cooling and powering schemes. The design of the new front-end readout chip comprises larger data buffers, an increased transmission bandwidth, and low-threshold comparators. These improvements allow the new pixel detector to sustain and improve t...

Non-streaming high-efficiency perforated semiconductor neutron detectors, methods of making same and measuring wand and detector modules utilizing same

Science.gov (United States)

McGregor, Douglas S.; Shultis, John K.; Rice, Blake B.; McNeil, Walter J.; Solomon, Clell J.; Patterson, Eric L.; Bellinger, Steven L.

2010-12-21

Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.

A high-throughput, multi-channel photon-counting detector with picosecond timing

CERN Document Server

Lapington, J S; Miller, G M; Ashton, T J R; Jarron, P; Despeisse, M; Powolny, F; Howorth, J; Milnes, J

2009-01-01

High-throughput photon counting with high time resolution is a niche application area where vacuum tubes can still outperform solid-state devices. Applications in the life sciences utilizing time-resolved spectroscopies, particularly in the growing field of proteomics, will benefit greatly from performance enhancements in event timing and detector throughput. The HiContent project is a collaboration between the University of Leicester Space Research Centre, the Microelectronics Group at CERN, Photek Ltd., and end-users at the Gray Cancer Institute and the University of Manchester. The goal is to develop a detector system specifically designed for optical proteomics, capable of high content (multi-parametric) analysis at high throughput. The HiContent detector system is being developed to exploit this niche market. It combines multi-channel, high time resolution photon counting in a single miniaturized detector system with integrated electronics. The combination of enabling technologies; small pore microchanne...

Assessment of ambient-temperature, high-resolution detectors for nuclear safeguards applications

International Nuclear Information System (INIS)

Ruhter, W.D.; McQuaid, J.H.; Lavietes, A.

1993-01-01

High-resolution, gamma- and x-ray spectrometry are used routinely in nuclear safeguards verification measurements of plutonium and uranium in the field. These measurements are now performed with high-purity germanium (HPGe) detectors that require cooling liquid-nitrogen temperatures, thus limiting their utility in field and unattended safeguards measurement applications. Ambient temperature semiconductor detectors may complement HPGe detectors for certain safeguards verification applications. Their potential will be determined by criteria such as their performance, commercial availability, stage of development, and costs. We have conducted as assessment of ambient temperature detectors for safeguards measurement applications with these criteria in mind

Ultrawide Bandwidth Receiver Based on a Multivariate Generalized Gaussian Distribution

KAUST Repository

Ahmed, Qasim Zeeshan

2015-04-01

Multivariate generalized Gaussian density (MGGD) is used to approximate the multiple access interference (MAI) and additive white Gaussian noise in pulse-based ultrawide bandwidth (UWB) system. The MGGD probability density function (pdf) is shown to be a better approximation of a UWB system as compared to multivariate Gaussian, multivariate Laplacian and multivariate Gaussian-Laplacian mixture (GLM). The similarity between the simulated and the approximated pdf is measured with the help of modified Kullback-Leibler distance (KLD). It is also shown that MGGD has the smallest KLD as compared to Gaussian, Laplacian and GLM densities. A receiver based on the principles of minimum bit error rate is designed for the MGGD pdf. As the requirement is stringent, the adaptive implementation of the receiver is also carried out in this paper. Training sequence of the desired user is the only requirement when implementing the detector adaptively. © 2002-2012 IEEE.

A Very High Spatial Resolution Detector for Small Animal PET

International Nuclear Information System (INIS)

Kanai Shah, M.S.

2007-01-01

Positron Emission Tomography (PET) is an in vivo analog of autoradiography and has the potential to become a powerful new tool in imaging biological processes in small laboratory animals. PET imaging of small animals can provide unique information that can help in advancement of human disease models as well as drug development. Clinical PET scanners used for human imaging are bulky, expensive and do not have adequate spatial resolution for small animal studies. Hence, dedicated, low cost instruments are required for conducting small animal studies with higher spatial resolution than what is currently achieved with clinical as well as dedicated small animal PET scanners. The goal of the proposed project is to investigate a new all solid-state detector design for small animal PET imaging. Exceptionally high spatial resolution, good timing resolution, and excellent energy resolution are expected from the proposed detector design. The Phase I project was aimed at demonstrating the feasibility of producing high performance solid-state detectors that provide high sensitivity, spatial resolution, and timing characteristics. Energy resolution characteristics of the new detector were also investigated. The goal of the Phase II project is to advance the promising solid-state detector technology for small animal PET and determine its full potential. Detectors modules will be built and characterized and finally, a bench-top small animal PET system will be assembled and evaluated

Application of Advanced Laser Diagnostics to High Impact Technologies. Delivery Order 0001: Laser Diagnostics Applications

Science.gov (United States)

2011-02-01

an f=75 mm fused-silica lens. Both detectors were UV-enhanced silicon p-i-n photodiodes built into a transimpedance amplifier circuit. The voltage...model included an integrated transimpedance amplifier . These detectors were cooled with liquid nitrogen to operate at 77 K. The bandwidth of these...tremendous peak powers for broad spectral coverage and non-linear signal generation. The high pulse-repetition rates of ultrafast oscillators and amplifiers

A Bandwidth-Optimized Multi-Core Architecture for Irregular Applications

Energy Technology Data Exchange (ETDEWEB)

Secchi, Simone; Tumeo, Antonino; Villa, Oreste

2012-05-31

This paper presents an architecture template for next-generation high performance computing systems specifically targeted to irregular applications. We start our work by considering that future generation interconnection and memory bandwidth full-system numbers are expected to grow by a factor of 10. In order to keep up with such a communication capacity, while still resorting to fine-grained multithreading as the main way to tolerate unpredictable memory access latencies of irregular applications, we show how overall performance scaling can benefit from the multi-core paradigm. At the same time, we also show how such an architecture template must be coupled with specific techniques in order to optimize bandwidth utilization and achieve the maximum scalability. We propose a technique based on memory references aggregation, together with the related hardware implementation, as one of such optimization techniques. We explore the proposed architecture template by focusing on the Cray XMT architecture and, using a dedicated simulation infrastructure, validate the performance of our template with two typical irregular applications. Our experimental results prove the benefits provided by both the multi-core approach and the bandwidth optimization reference aggregation technique.

ATLAS ITk Strip Detector for High-Luminosity LHC

CERN Document Server

Kroll, Jiri; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High-Luminosity LHC that is scheduled for 2026. The expected peak instantaneous luminosity up to 7.5E34 per second and cm2 corresponding to approximately 200 inelastic proton-proton interactions per beam crossing, radiation damage at an integrated luminosity of 3000/fb and hadron fluencies over 1E16 1 MeV neutron equivalent per cm2, as well as fast hardware tracking capability that will bring Level-0 trigger rate of a few MHz down to a Level-1 trigger rate below 1 MHz require a replacement of existing Inner Detector by an all-silicon Inner Tracker (ITk) with a pixel detector surrounded by a strip detector. The current prototyping phase, that is working with ITk Strip Detector consisting of a four-layer barrel and a forward region composed of six discs on each side of the barrel, has resulted in the ATLAS ITk Strip Detector Technical Design Report (TDR), which starts the pre-production readiness phase at the ...

ATLAS ITk Strip Detector for High-Luminosity LHC

CERN Document Server

Kroll, Jiri; The ATLAS collaboration

2017-01-01

The ATLAS experiment is currently preparing for an upgrade of the tracking system in the course of the High-Luminosity LHC that is scheduled for 2026. The expected peak instantaneous luminosity up to $7.5\\times10^{34}\\;\\mathrm{cm}^{-2}\\mathrm{s}^{-1}$ corresponding to approximately 200 inelastic proton-proton interactions per beam crossing, radiation damage at an integrated luminosity of $3000\\;\\mathrm{fb}^{-1}$ and hadron fluencies over $2\\times10^{16}\\;\\mathrm{n}_{\\mathrm{eq}}/\\mathrm{cm}^{2}$, as well as fast hardware tracking capability that will bring Level-0 trigger rate of a few MHz down to a Level-1 trigger rate below 1 MHz require a replacement of existing Inner Detector by an all-silicon Inner Tracker with a pixel detector surrounded by a strip detector. The current prototyping phase, that is working with ITk Strip Detector consisting of a four-layer barrel and a forward region composed of six disks on each side of the barrel, has resulted in the ATLAS Inner Tracker Strip Detector Technical Design R...

High-spatial resolution and high-spectral resolution detector for use in the measurement of solar flare hard x rays

International Nuclear Information System (INIS)

Desai, U.D.; Orwig, L.E.

1988-01-01

In the areas of high spatial resolution, the evaluation of a hard X-ray detector with 65 micron spatial resolution for operation in the energy range from 30 to 400 keV is proposed. The basic detector is a thick large-area scintillator faceplate, composed of a matrix of high-density scintillating glass fibers, attached to a proximity type image intensifier tube with a resistive-anode digital readout system. Such a detector, combined with a coded-aperture mask, would be ideal for use as a modest-sized hard X-ray imaging instrument up to X-ray energies as high as several hundred keV. As an integral part of this study it was also proposed that several techniques be critically evaluated for X-ray image coding which could be used with this detector. In the area of high spectral resolution, it is proposed to evaluate two different types of detectors for use as X-ray spectrometers for solar flares: planar silicon detectors and high-purity germanium detectors (HPGe). Instruments utilizing these high-spatial-resolution detectors for hard X-ray imaging measurements from 30 to 400 keV and high-spectral-resolution detectors for measurements over a similar energy range would be ideally suited for making crucial solar flare observations during the upcoming maximum in the solar cycle

PIC Simulation of Laser Plasma Interactions with Temporal Bandwidths

Science.gov (United States)

Tsung, Frank; Weaver, J.; Lehmberg, R.

2015-11-01

We are performing particle-in-cell simulations using the code OSIRIS to study the effects of laser plasma interactions in the presence of temperal bandwidths under conditions relevant to current and future shock ignition experiments on the NIKE laser. Our simulations show that, for sufficiently large bandwidth, the saturation level, and the distribution of hot electrons, can be effected by the addition of temporal bandwidths (which can be accomplished in experiments using smoothing techniques such as SSD or ISI). We will show that temporal bandwidth along play an important role in the control of LPI's in these lasers and discuss future directions. This work is conducted under the auspices of NRL.

Hard x-ray monochromator with milli-electron volt bandwidth for high-resolution diffraction studies of diamond crystals

Energy Technology Data Exchange (ETDEWEB)

Stoupin, Stanislav; Shvyd' ko, Yuri; Shu Deming; Khachatryan, Ruben; Xiao, Xianghui; DeCarlo, Francesco; Goetze, Kurt; Roberts, Timothy; Roehrig, Christian; Deriy, Alexey [Advanced Photon Source, Argonne National Laboratory, Illinois 60439 (United States)

2012-02-15

We report on design and performance of a high-resolution x-ray monochromator with a spectral bandwidth of {Delta}E{sub X}{approx_equal} 1.5 meV, which operates at x-ray energies in the vicinity of the backscattering (Bragg) energy E{sub H} = 13.903 keV of the (008) reflection in diamond. The monochromator is utilized for high-energy-resolution diffraction characterization of diamond crystals as elements of advanced x-ray crystal optics for synchrotrons and x-ray free-electron lasers. The monochromator and the related controls are made portable such that they can be installed and operated at any appropriate synchrotron beamline equipped with a pre-monochromator.

A high resolution germanium detector array for hypernuclear studies at PANDA

Energy Technology Data Exchange (ETDEWEB)

Bleser, Sebastian; Sanchez Lorente, Alicia; Steinen, Marcell [Helmholtz-Institut Mainz (Germany); Gerl, Juergen; Kojouharova, Jasmina; Kojouharov, Ivan [GSI Darmstadt (Germany); Iazzi, Felice [Politecnico, Torino (Italy); INFN, Torino (Italy); Pochodzalla, Josef; Rittgen, Kai; Sahin, Cihan [Institute for Nuclear Physics, JGU Mainz (Germany)

2014-07-01

The PANDA experiment, planned at the FAIR facility in Darmstadt, aims at the high resolution γ-spectroscopy of double Λ hypernuclei. For this purpose a devoted detector setup is required, consisting of a primary nuclear target, an active secondary target and a germanium detector array for the γ-spectroscopy. Due to the limited space within the PANDA detector a compact design is required. In particular the conventional LN{sub 2} cooling system must be replaced by an electro mechanical device and a new arrangement of the crystals is needed. This presentation shows the progress in the development of the germanium detectors. First results of in-beam measurements at COSY with a new electro mechanically cooled single crystal prototype are presented. Digital pulse shape analysis is used to disentangle pile up events due to the high event rate. This analysis technique also allows to recover the high original energy resolution in case of neutron damage. Finally the status of the new triple crystal detector prototype is given.

Electronics for very high rate tracking detectors

International Nuclear Information System (INIS)

Williams, H.H.; Dressnandt, N.; Ekenberg, T.; Gerds, E.J.; Newcomer, F.M.; Tedja, S.; Van Berg, R.; Van der Speigel, J.

1995-01-01

Results are presented on a system of electronics designed for very high rate tracking detectors at the SSC and LHC. The primary goal was a system for signal detection, time measurement, and readout for the straw tracker for SDC. An integrated circuit incorporating eight channels of amplifier-shaper-discriminator (including detector tail cancellation), and two different integrated circuits for time measurement are described. The performance of tracking measurements up to counting rates of 8 MHz per wire is reported, as well as preliminary results from a baseline restoration circuit. (orig.)

Performance of high-resolution position-sensitive detectors developed for storage-ring decay experiments

International Nuclear Information System (INIS)

Yamaguchi, T.; Suzaki, F.; Izumikawa, T.; Miyazawa, S.; Morimoto, K.; Suzuki, T.; Tokanai, F.; Furuki, H.; Ichihashi, N.; Ichikawa, C.; Kitagawa, A.; Kuboki, T.; Momota, S.; Nagae, D.; Nagashima, M.; Nakamura, Y.; Nishikiori, R.; Niwa, T.; Ohtsubo, T.; Ozawa, A.

2013-01-01

Highlights: • Position-sensitive detectors were developed for storage-ring decay spectroscopy. • Fiber scintillation and silicon strip detectors were tested with heavy ion beams. • A new fiber scintillation detector showed an excellent position resolution. • Position and energy detection by silicon strip detectors enable full identification. -- Abstract: As next generation spectroscopic tools, heavy-ion cooler storage rings will be a unique application of highly charged RI beam experiments. Decay spectroscopy of highly charged rare isotopes provides us important information relevant to the stellar conditions, such as for the s- and r-process nucleosynthesis. In-ring decay products of highly charged RI will be momentum-analyzed and reach a position-sensitive detector set-up located outside of the storage orbit. To realize such in-ring decay experiments, we have developed and tested two types of high-resolution position-sensitive detectors: silicon strips and scintillating fibers. The beam test experiments resulted in excellent position resolutions for both detectors, which will be available for future storage-ring experiments

Influence of Reduced Graphene Oxide on Effective Absorption Bandwidth Shift of Hybrid Absorbers.

Science.gov (United States)

Ameer, Shahid; Gul, Iftikhar Hussain

2016-01-01

The magnetic nanoparticle composite NiFe2O4 has traditionally been studied for high-frequency microwave absorption with marginal performance towards low-frequency radar bands (particularly L and S bands). Here, NiFe2O4 nanoparticles and nanohybrids using large-diameter graphene oxide (GO) sheets are prepared via solvothermal synthesis for low-frequency wide bandwidth shielding (L and S radar bands). The synthesized materials were characterized using XRD, SEM, FTIR and microwave magneto dielectric spectroscopy. The dimension of these solvothermally synthesized pristine particles and hybrids lies within 30-58 nm. Microwave magneto-dielectric spectroscopy was performed in the low-frequency region in the 1 MHz-3 GHz spectrum. The as-synthesized pristine nanoparticles and hybrids were found to be highly absorbing for microwaves throughout the L and S radar bands (graphene sheet coupling shows application of these materials with absorption bandwidth which is tailored such that these could be used for low frequency. Previously, these were used for high frequency absorptions (typically > 4 GHz) with limited selective bandwidth.

HPGe detectors long time behaviour in high-resolution γ spectrometry

International Nuclear Information System (INIS)

Sajo-Bohus, L.; Rosso, D.; Sajo Castelli, A.M.; Napoli, D.R.; Fioretto, E.; Menegazzo, R.; Barros, H.; Ur, C.A.; Palacios, D.; Liendo, J.

2011-01-01

A large set of data on long term performance of n-type HPGe detectors used in GASP, EUROBALL and CLARA γ spectrometers, as well as environmental measurements have been collected over two decades. In this paper a detailed statistical analysis of this data is given and detector long term behaviour is provided to the scientific community. We include failure, failure mode, repair frequency, repair outcome and its influence in the energy efficiency and energy resolution. A remarkable result is that the life span distribution is exponential. A detector's failure is a memory-less process, where a previous failure does not influence the upcoming one. Repaired spectrometers result in high reliability with deep implications in the management of large scale high-resolution gamma spectrometry related projects. Findings show that on average, detectors initial counting efficiency is slightly lower (∼2%) than that reported by the manufacturers and the repair process (including annealing) does not affect significantly the energy efficiency, even after a long period of use. Repaired detector energy resolution statistics show that the probability, that a repaired detector will be at least as good as it was originally, is more than 3/4.

12 GeV detector technology at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Leckey, John P. [Indiana University, Bloomington, IN 47405 (United States); Collaboration: GlueX Collaboration

2013-04-19

The Thomas Jefferson National Accelerator Facility (JLab) is presently in the middle of an upgrade to increase the energy of its CW electron beam from 6 GeV to 12 GeV along with the addition of a fourth experimental hall. Driven both by necessity and availability, novel detectors and electronics modules have been used in the upgrade. One such sensor is the Silicon Photomultiplier (SiPM), specifically a Multi-Pixel Photon Counter (MPPC), which is an array of avalanche photodiode pixels operating in Geiger mode that are used to sense photons. The SiPMs replace conventional photomultiplier tubes and have several distinct advantages including the safe operation in a magnetic field and the lack of need for high voltage. Another key to 12 GeV success is advanced fast electronics. Jlab will use custom 250 MHz and 125 MHz 12-bit analog to digital converters (ADCs) and time to digital converters (TDCs) all of which take advantage of VME Switched Serial (VXS) bus with its GB/s high bandwidth readout capability. These new technologies will be used to readout drift chambers, calorimeters, spectrometers and other particle detectors at Jlab once the 12 GeV upgrade is complete. The largest experiment at Jlab utilizing these components is GlueX - an experiment in the newly constructed Hall D that will study the photoproduction of light mesons in the search for hybrid mesons. The performance of these components and their respective detectors will be presented.

Fluid Limits for Bandwidth-Sharing Networks in Overload.

NARCIS (Netherlands)

Borst, S.; Egorova, R.; Zwart, A.P.

2014-01-01

Bandwidth-sharing networks as considered by Roberts and Massoulié [28] (Roberts JW, Massoulié L (1998) Bandwidth sharing and admission control for elastic traffic. Proc. ITC Specialist Seminar, Yokohama, Japan) provide a natural modeling framework for describing the dynamic flow-level interaction

Fluid limits for bandwidth-sharing networks in overload

NARCIS (Netherlands)

Borst, S.C.; Egorova, R.R.; Zwart, B.

2014-01-01

Bandwidth-sharing networks as considered by Roberts and Massoulié [28] (Roberts JW, Massoulié L (1998) Bandwidth sharing and admission control for elastic traffic. Proc. ITC Specialist Seminar, Yokohama, Japan) provide a natural modeling framework for describing the dynamic flow-level interaction

Transducers for the Brazilian gravitational wave detector 'Mario Schenberg'

International Nuclear Information System (INIS)

Frajuca, Carlos; Ribeiro, Kilder L; Andrade, Luiz A; Jr, Walter F Velloso; Melo, Jose L; Aguiar, Odylio D; Magalhaes, Nadja S

2002-01-01

'Mario Schenberg' is a spherical resonant-mass gravitational wave (GW) detector that will be part of a GW detection array of three detectors. The other two will be built in Italy and the Netherlands. Their resonant frequencies will be around 3.2 kHz with a bandwidth of about 200 Hz. This range of frequencies is new in a field where the typical frequencies lie below 1 kHz, making the transducer development much more complex. In this paper, the design of the mechanical part of the transducer will be shown, as well as the attachment method to the sphere and the expected sensitivity

Development of high efficiency neutron detectors

International Nuclear Information System (INIS)

Pickrell, M.M.; Menlove, H.O.

1993-01-01

The authors have designed a novel neutron detector system using conventional 3 He detector tubes and composites of polyethylene and graphite. At this time the design consists entirely of MCNP simulations of different detector configurations and materials. These detectors are applicable to low-level passive and active neutron assay systems such as the passive add-a-source and the 252 Cf shuffler. Monte Carlo simulations of these neutron detector designs achieved efficiencies of over 35% for assay chambers that can accommodate 55-gal. drums. Only slight increases in the number of detector tubes and helium pressure are required. The detectors also have reduced die-away times. Potential applications are coincident and multiplicity neutron counting for waste disposal and safeguards. The authors will present the general design philosophy, underlying physics, calculation mechanics, and results

CVD Diamond Sensors In Detectors For High Energy Physics

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00334150; Trischuk, William

At the end of the next decade an upgrade of the Large Hadron Collider (LHC) to High Luminosity LHC (HL-LHC) is planned which requires the development of new radiation tolerant sensor technology. Diamond is an interesting material for use as a particle detector in high radiation environments. The large band gap ($5.47\\,\\text{eV}$) and the large displacement energy suggest that diamond is a radiation tolerant detector material. In this Thesis the capability of Chemical Vapor Deposition (CVD) diamond as such a sensor technology is investigated. The radiation damage constant for $800\\,\\text{MeV}$ protons is measured using single crystalline CVD (scCVD) and polycrystalline CVD (pCVD) diamonds irradiated to particle fluences up to $12 \\times 10^{15}\\,\\text{p/cm}^2$. In addition the signal response of a pCVD diamond detector after an irradiation to $12 \\times 10^{15}\\,\\text{p/cm}^2$ is investigated to determine if such a detector can be operated efficiently in the expected HL-LHC environment. By using electrodes em...

Timing performance measurements of Si-PM-based LGSO phoswich detectors

International Nuclear Information System (INIS)

Yamamoto, Seiichi; Kobayashi, Takahiro; Okumura, Satoshi; Yeom, Jung Yeol

2016-01-01

Since the timing resolution was significantly improved using silicon photomultipliers (Si-PMs) combined with fast scintillators, we expect that phoswich detectors will be used in future TOF-PET systems. However, no practical phoswich detector has been proposed for TOF-PET detectors. We conducted timing performance measurements of phoswich detectors comprised of two types of Ce-doped LGSO scintillators with different decay times coupled to Si-PMs and digitized the output signals using a high bandwidth digital oscilloscope. We prepared three types of LGSOs (LGSO-fast, LGSO-standard, and LGSO-slow) with different Ce concentrations. After measuring the decay time, the energy performance, and the timing performance of each LGSO, we conducted pulse shape analysis and timing resolution measurements for two versions of phoswich LGSOs: LGSO-standard/LGSO-fast and LGSO-slow/LGSO-fast combinations. The pulse shape spectra for a 10-mm-long crystal LGSO-slow/LGSO-fast combination showed good separation of the front and back crystals with a peak-to-valley ratio of 2.0. The timing resolutions for the 20-mm-long crystal LGSO-slow/LGSO-fast combination were ~300 ps FWHM. The timing resolutions for the phoswich LGSOs were slightly inferior than that measured with the individual LGSO fast, but the acquired timing resolution for the phoswich configuration, ~300 ps with a LGSO-slow/LGSO-fast combination, is adequate for TOF-PET systems. We conclude that LGSO phoswich detectors are promising for TOF-DOI-PET systems.

Microfluidic Scintillation Detectors for High Energy Physics

CERN Document Server

Maoddi, Pietro; Mapelli, Alessandro

This thesis deals with the development and study of microfluidic scintillation detectors, a technology of recent introduction for the detection of high energy particles. Most of the interest for such devices comes from the use of a liquid scintillator, which entails the possibility of changing the active material in the detector, leading to increased radiation resistance. A first part of the thesis focuses on the work performed in terms of design and modelling studies of novel prototype devices, hinting to new possibilities and applications. In this framework, the simulations performed to validate selected designs and the main technological choices made in view of their fabrication are addressed. The second part of this thesis deals with the microfabrication of several prototype devices. Two different materials were studied for the manufacturing of microfluidic scintillation detectors, namely the SU-8 photosensitive epoxy and monocrystalline silicon. For what concerns the former, an original fabrication appro...

Alpha-ray spectrometry at high temperature by using a compound semiconductor detector.

Science.gov (United States)

Ha, Jang Ho; Kim, Han Soo

2013-11-01

The use of conventional radiation detectors in harsh environments is limited by radiation damage to detector materials and by temperature constraints. We fabricated a wide-band gap semiconductor radiation detector based on silicon carbide. All the detector components were considered for an application in a high temperature environment like a nuclear reactor core. The radiation response, especially to alpha particles, was measured using an (241)Am source at variable operating voltages at room temperature in the air. The temperature on detector was controlled from 30°C to 250°C. The alpha-particle spectra were measured at zero bias operation. Even though the detector is operated at high temperature, the energy resolution as a function of temperature is almost constant within 3.5% deviation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Studies of bandwidth dependence of laser plasma instabilities driven by the Nike laser

Science.gov (United States)

Weaver, J.; Kehne, D.; Obenschain, S.; Serlin, V.; Schmitt, A. J.; Oh, J.; Lehmberg, R. H.; Brown, C. M.; Seely, J.; Feldman, U.

2012-10-01

Experiments at the Nike laser facility of the Naval Research Laboratory are exploring the influence of laser bandwidth on laser plasma instabilities (LPI) driven by a deep ultraviolet pump (248 nm) that incorporates beam smoothing by induced spatial incoherence (ISI). In early ISI studies with longer wavelength Nd:glass lasers (1054 nm and 527 nm),footnotetextObenschain, PRL 62(1989);Mostovych, PRL 62(1987);Peyser, Phys. Fluids B 3(1991). stimulated Raman scattering, stimulated Brillouin scattering, and the two plasmon decay instability were reduced when wide bandwidth ISI (δν/ν˜0.03-0.19%) pulses irradiated targets at moderate to high intensities (10^14-10^15 W/cm^2). The current studies will compare the emission signatures of LPI from planar CH targets during Nike operation at large bandwidth (δν˜1THz) to observations for narrower bandwidth operation (δν˜0.1-0.3THz). These studies will help clarify the relative importance of the short wavelength and wide bandwidth to the increased LPI intensity thresholds observed at Nike. New pulse shapes are being used to generate plasmas with larger electron density scale-lengths that are closer to conditions during pellet implosions for direct drive inertial confinement fusion.

International workshop on advanced materials for high precision detectors. Proceedings

International Nuclear Information System (INIS)

Nicquevert, B.; Hauviller, C.

1994-01-01

These proceedings gather together the contributions to the Workshop on Advanced Materials for High Precision Detectors, which was held from 28-30 September 1994 in Archamps, Haute-Savoie, France. This meeting brought together international experts (researchers, physicists and engineers) in the field of advanced materials and their use in high energy physics detectors or spacecraft applications. Its purpose was to discuss the status of the different materials currently in use in the structures of detectors and spacecraft, together with their actual performances, technological implications and future prospects. Environmental effects, such as those of moisture and radiation, were discussed, as were design and manufacturing technologies. Some case studies were presented. (orig.)

Investigating the influence of chromatic aberration and optical illumination bandwidth on fundus imaging in rats

Science.gov (United States)

Li, Hao; Liu, Wenzhong; Zhang, Hao F.

2015-10-01

Rodent models are indispensable in studying various retinal diseases. Noninvasive, high-resolution retinal imaging of rodent models is highly desired for longitudinally investigating the pathogenesis and therapeutic strategies. However, due to severe aberrations, the retinal image quality in rodents can be much worse than that in humans. We numerically and experimentally investigated the influence of chromatic aberration and optical illumination bandwidth on retinal imaging. We confirmed that the rat retinal image quality decreased with increasing illumination bandwidth. We achieved the retinal image resolution of 10 μm using a 19 nm illumination bandwidth centered at 580 nm in a home-built fundus camera. Furthermore, we observed higher chromatic aberration in albino rat eyes than in pigmented rat eyes. This study provides a design guide for high-resolution fundus camera for rodents. Our method is also beneficial to dispersion compensation in multiwavelength retinal imaging applications.

Semiconductor devices as track detectors in high energy colliding beam experiments

International Nuclear Information System (INIS)

Ludlam, T.

1980-01-01

In considering the design of experiments for high energy colliding beam facilities one quickly sees the need for better detectors. The full exploitation of machines like ISABELLE will call for detector capabilities beyond what can be expected from refinements of the conventional approaches to particle detection in high energy physics experiments. Over the past year or so there has been a general realization that semiconductor device technology offers the possibility of position sensing detectors having resolution elements with dimensions of the order of 10 microns or smaller. Such a detector could offer enormous advantages in the design of experiments, and the purpose of this paper is to discuss some of the possibilities and some of the problems

Semiconductor devices as track detectors in high energy colliding beam experiments

Energy Technology Data Exchange (ETDEWEB)

Ludlam, T

1980-01-01

In considering the design of experiments for high energy colliding beam facilities one quickly sees the need for better detectors. The full exploitation of machines like ISABELLE will call for detector capabilities beyond what can be expected from refinements of the conventional approaches to particle detection in high energy physics experiments. Over the past year or so there has been a general realization that semiconductor device technology offers the possibility of position sensing detectors having resolution elements with dimensions of the order of 10 microns or smaller. Such a detector could offer enormous advantages in the design of experiments, and the purpose of this paper is to discuss some of the possibilities and some of the problems.

Silicon microstrip detector development in the Institute for High Energy Physics Zeuthen, GDR

International Nuclear Information System (INIS)

Lange, W.; Nowak, W.D.; Truetzschler, K.

1990-01-01

This paper reports that in regard of the growing interest to study short living particles demanding for high resolution vertex detectors the authors started to build Si microstrip detectors. The first detector generation was characterized by a small area of silicon and a readout via printed circuit board fan out. Now they can assemble detectors with larger areas and VLSI readout. A special cleanroom has been built. Equipment and tools necessary are available. Silicon wafers and thick film hybrid circuits are fabricated under collaboration by the GDR industry. Applications of their detectors were several test-runs at CERN to calibrate the L3 time expansion chamber (TEC) and the L3 muon chambers. A 10-layer telescope is designed now and it is planned to calibrate a high resolution scintillation fiber target. Future applications will be high resolution vertex detectors, e.g. L3 upgrading (LEP, CERN) or KEDR (VEPP-5, Novosibirsk). Further investigations will concern AC coupled strip detectors (single and double sided) and pixel and/or pad detectors

FELIX: the New Detector Interface for the ATLAS Experiment arXiv

CERN Document Server

Wu, Weihao

During the next major shutdown (2019-2020), the ATLAS experiment at the LHC will adopt the Front-End Link eXchange (FELIX) system as the interface between the data acquisition, detector control and TTC (Timing, Trigger and Control) systems and new or updated trigger and detector front-end electronics. FELIX will function as a router between custom serial links from front-end ASICs and FPGAs to data collection and processing components via a commodity switched network. Links may aggregate many slower links or be a single high bandwidth link. FELIX will also forward the LHC bunch-crossing clock, fixed latency trigger accepts and resets received from the TTC system to front-end electronics. The FELIX system uses commodity server technology in combination with FPGA-based PCIe I/O cards. The FELIX servers will run a software routing platform serving data to network clients. Commodity servers connected to FELIX systems via the same network will run the new Software Readout Driver (SW ROD) infrastructure for event f...

New high-gain thin-gap detector for the OPAL hadron calorimeter

Energy Technology Data Exchange (ETDEWEB)

Dado, S; Goldberg, J; Lupu, N; Mincer, A I; Alexander, G; Bella, G; Gnat, Y; Grunhaus, J; Levy, A; Cohen, J

1986-12-01

A new type of thin-gap multiwire gas detector operating in a high-gain mode was developed for use in the OPAL pole-tip calorimeter. The detector thickness is only 6.6 mm and its area is 0.61 m/sup 2/. The induced pad readout provides high output pulses that require no amplification. The setup for the detector mass production and quality-control test is described. Results from a test beam setup that simulates the OPAL pole-tip calorimeter are presented and compared with computer simulations.

Motivation for an SSC detector with ultra-high resolution photon detection

International Nuclear Information System (INIS)

Gunion, J.F.; Kane, G.

1992-01-01

It is well known that incorporating ultra-high resolution photon detection into a general purpose detector for the SSC will be extremely difficult. The authors will argue that the physics signals that could be missed without such resolution are of such importance that a special purpose detector designed specifically for photon final state modes should be constructed, if sufficient resolution cannot be achieved with general purpose detectors. The potentially great value of these signals as a probe of extremely high mass scales is stressed

Bandwidth selection in smoothing functions | Kibua | East African ...

African Journals Online (AJOL)

... inexpensive and, hence, worth adopting. We argue that the bandwidth parameter is determined by two factors: the kernel function and the length of the smoothing region. We give an illustrative example of its application using real data. Keywords: Kernel, Smoothing functions, Bandwidth > East African Journal of Statistics ...

Design optimization of the distributed modal filtering rod fiber for increasing single mode bandwidth

DEFF Research Database (Denmark)

Jørgensen, Mette Marie; Petersen, Sidsel Rübner; Laurila, Marko

2012-01-01

. Large preform tolerances are compensated during the fiber draw resulting in ultra low NA fibers with very large cores. In this paper, design optimization of the SM bandwidth of the DMF rod fiber is presented. Analysis of band gap properties results in a fourfold increase of the SM bandwidth compared...... LMA fiber amplifiers having high pump absorption through a pump cladding that is decoupled from the outer fiber. However, achieving ultra low NA for single-mode (SM) guidance is challenging, and thus different design strategies must be applied to filter out higher order modes (HOMs). The novel...... distributed modal filtering (DMF) design presented here enables SM guidance, and previous results have shown a SM mode field diameter of 60 μm operating in a 20 nm SM bandwidth. The DMF rod fiber has high index ring-shaped inclusions acting as resonators enabling SM guidance through modal filtering of HOMs...

A 3D CZT high resolution detector for x- and gamma-ray astronomy

DEFF Research Database (Denmark)

Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Zappettini, A.

2014-01-01

At DTU Space we have developed a high resolution three dimensional (3D) position sensitive CZT detector for high energy astronomy. The design of the 3D CZT detector is based on the CZT Drift Strip detector principle. The position determination perpendicular to the anode strips is performed using...

High energy radiation detector

International Nuclear Information System (INIS)

Vosburgh, K.G.

1975-01-01

The high energy radiation detector described comprises a set of closely spaced wedge reflectors. Each wedge reflector is composed of three sides forming identical isoceles triangles with a common apex and an open base forming an equilateral triangle. The length of one side of the base is less than the thickness of the coat of material sensitive to high energy radiation. The wedge reflectors reflect the light photons spreading to the rear of the coat in such a way that each reflected track is parallel to the incident track of the light photon spreading rearwards. The angle of the three isosceles triangles with a common apex is between 85 and 95 deg. The first main surface of the coat of high energy radiation sensitive material is in contact with the projecting edges of the surface of the wedge reflectors of the reflecting element [fr

Orientation masking and cross-orientation suppression (XOS): implications for estimates of filter bandwidth.

Science.gov (United States)

Meese, Tim S; Holmes, David J

2010-10-01

Most contemporary models of spatial vision include a cross-oriented route to suppression (masking from a broadly tuned inhibitory pool), which is most potent at low spatial and high temporal frequencies (T. S. Meese & D. J. Holmes, 2007). The influence of this pathway can elevate orientation-masking functions without exciting the target mechanism, and because early psychophysical estimates of filter bandwidth did not accommodate this, it is likely that they have been overestimated for this corner of stimulus space. Here we show that a transient 40% contrast mask causes substantial binocular threshold elevation for a transient vertical target, and this declines from a mask orientation of 0° to about 40° (indicating tuning), and then more gently to 90°, where it remains at a factor of ∼4. We also confirm that cross-orientation masking is diminished or abolished at high spatial frequencies and for sustained temporal modulation. We fitted a simple model of pedestal masking and cross-orientation suppression (XOS) to our data and those of G. C. Phillips and H. R. Wilson (1984) and found the dependency of orientation bandwidth on spatial frequency to be much less than previously supposed. An extension of our linear spatial pooling model of contrast gain control and dilution masking (T. S. Meese & R. J. Summers, 2007) is also shown to be consistent with our results using filter bandwidths of ±20°. Both models include tightly and broadly tuned components of divisive suppression. More generally, because XOS and/or dilution masking can affect the shape of orientation-masking curves, we caution that variations in bandwidth estimates might reflect variations in processes that have nothing to do with filter bandwidth.

Polybinary modulation for bandwidth limited optical links

DEFF Research Database (Denmark)

Vegas Olmos, Juan José; Jurado-Navas, Antonio

2015-01-01

form of partial response modulation, employs simple codification and filtering at the transmitter to drastically increase the spectral efficiency. At the receiver side, poly binary modulation requires low complexity direct detection and very little digital signal processing. This talk will review...... the recent results on poly binary modulation, comprising both binary and multilevel signals as seed signals. The results will show how poly binary modulation effectively reduces the bandwidth requirements on optical links while providing high spectral efficiency....

New high gain thin gap detector for the OPAL hadron calorimeter

Energy Technology Data Exchange (ETDEWEB)

Dado, S; Goldberg, J; Lupu, N; Mincer, A I; Alexander, G; Bella, G; Gnat, Y; Grunhaus, J; Levy, A; Cohen, J

1986-12-01

A new type of thin gap multiwire gas detector operating in a high gain mode has been developed for use in the OPAL pole tip calorimeter. The detector thickness is only 6.6 mm and its area is 0.61 m/sup 2/. The induced pad readout provides high output pulses which require no amplification. The set-up for the detector mass production and quality control test is described. Results from a test beam set-up that simulates the OPAL pole tip calorimeter are presented and compared with computer simulations.

Neutrino hierarchy from CP-blind observables with high density magnetized detectors

International Nuclear Information System (INIS)

Donini, A.; Fernandez-Martinez, E.; Rigolin, S.; Migliozzi, P.; Scotto Lavina, L.; Selvi, M.; Tabarelli de Fatis, T.; Terranova, F.

2008-01-01

High density magnetized detectors are well suited to exploit the outstanding purity and intensities of novel neutrino sources like neutrino factories and beta beams. They can also provide independent measurements of leptonic mixing parameters through the observation of atmospheric muon-neutrinos. In this paper, we discuss the combination of these observables from a multi-kT iron detector and a high energy beta beam; in particular, we demonstrate that even with moderate detector granularities the neutrino mass hierarchy can be determined for θ 13 values greater than 4 . (orig.)

The next science run of the gravitational wave detector NAUTILUS

CERN Document Server

Astone, P; Bassan, M; Bonifazi, P; Coccia, E; D'Antonio, S; Fafone, V; Giordano, G; Marini, A; Minenkov, Y; Modena, I; Modestino, G; Moleti, A; Pallottino, G V; Pizzella, G; Quintieri, L; Rocchi, A; Ronga, F; Terenzi, R; Visco, M

2002-01-01

The ultra-cryogenic gravitational wave detector NAUTILUS is gathering data in Frascati (Rome), in its second science run since June 1998. The measured strain sensitivity at the two resonances is 4 x 10 sup - sup 2 sup 2 Hz sup - sup 1 sup / sup 2 over a bandwidth of 1 Hz and better than 3 x 10 sup - sup 2 sup 0 Hz sup - sup 1 sup / sup 2 over a band of about 25 Hz, with a duty cycle of about 80%, mainly limited by cryogenic operations. At the beginning of 2002, the detector will be upgraded with a new Al bar, transducer and SQUID, and will be tuned to the 935 Hz frequency of the recently discovered pulsar in SN 1987A. The future sensitivity of the detector is presented and discussed.

Performance of GEM detectors in high intensity particle beams

CERN Document Server

Bachmann, S; Ketzer, B; Deutel, M; Ropelewski, Leszek; Sauli, Fabio; Bondar, A E; Buzulutskov, A F; Shekhtman, L I; Sokolov, A; Tatarinov, A A; Vasilev, A; Kappler, S; Schulte, E C

2001-01-01

We describe extensive tests of Double GEM and Triple GEM detectors, including full size prototypes for the COMPASS experiment, exposed to high intensity muon, proton and pion beams at the Paul~Scherrer Institute and at CERN. The measurements aim at detecting problems possible under these operation conditions, the main concern being the occurrence of discharges induced by beam particles. Results on the dependence of the probability for induced discharges on the experimental environment are presented and discussed. Implications for the application of GEM~detectors in experiments at high luminosity colliders are illustrated.

Toward achieving flexible and high sensitivity hexagonal boron nitride neutron detectors

Science.gov (United States)

Maity, A.; Grenadier, S. J.; Li, J.; Lin, J. Y.; Jiang, H. X.

2017-07-01

Hexagonal boron nitride (h-BN) detectors have demonstrated the highest thermal neutron detection efficiency to date among solid-state neutron detectors at about 51%. We report here the realization of h-BN neutron detectors possessing one order of magnitude enhancement in the detection area but maintaining an equal level of detection efficiency of previous achievement. These 3 mm × 3 mm detectors were fabricated from 50 μm thick freestanding and flexible 10B enriched h-BN (h-10BN) films, grown by metal organic chemical vapor deposition followed by mechanical separation from sapphire substrates. Mobility-lifetime results suggested that holes are the majority carriers in unintentionally doped h-BN. The detectors were tested under thermal neutron irradiation from californium-252 (252Cf) moderated by a high density polyethylene moderator. A thermal neutron detection efficiency of ˜53% was achieved at a bias voltage of 200 V. Conforming to traditional solid-state detectors, the realization of h-BN epilayers with enhanced electrical transport properties is the key to enable scaling up the device sizes. More specifically, the present results revealed that achieving an electrical resistivity of greater than 1014 Ωṡcm and a leakage current density of below 3 × 10-10 A/cm2 is needed to fabricate large area h-BN detectors and provided guidance for achieving high sensitivity solid state neutron detectors based on h-BN.

Automation of the Characterization of High Purity Germanium Detectors

Science.gov (United States)

Dugger, Charles ``Chip''

2014-09-01

Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of the detectors must be characterized. A robotic arm is being tested for future calibration of HPGe detectors. The arm will hold a source at locations relative to the crystal while data is acquired. Several radioactive sources of varying energy levels will be used to determine the characteristics of the crystal. In this poster, I will present our work with the robot, as well as the characterization of data we took with an underground HPGe detector at the WIPP facility in Carlsbad, NM (2013). Neutrinoless double beta decay is a rare hypothesized process that may yield valuable insight into the fundamental properties of the neutrino. Currently there are several experiments trying to observe this process, including the Majorana DEMONSTRAOR experiment, which uses high purity germanium (HPGe) detectors to generate and search for these events. Because the event happens internally, it is essential to have the lowest background possible. This is done through passive detector shielding, as well as event discrimination techniques that distinguish between multi-site events characteristic of gamma-radiation, and single-site events characteristic of neutrinoless double beta decay. Before fielding such an experiment, the radiation response of

Bandwidth-sharing in LHCONE, an analysis of the problem

Science.gov (United States)

Wildish, T.

2015-12-01

The LHC experiments have traditionally regarded the network as an unreliable resource, one which was expected to be a major source of errors and inefficiency at the time their original computing models were derived. Now, however, the network is seen as much more capable and reliable. Data are routinely transferred with high efficiency and low latency to wherever computing or storage resources are available to use or manage them. Although there was sufficient network bandwidth for the experiments’ needs during Run-1, they cannot rely on ever-increasing bandwidth as a solution to their data-transfer needs in the future. Sooner or later they need to consider the network as a finite resource that they interact with to manage their traffic, in much the same way as they manage their use of disk and CPU resources. There are several possible ways for the experiments to integrate management of the network in their software stacks, such as the use of virtual circuits with hard bandwidth guarantees or soft real-time flow-control, with somewhat less firm guarantees. Abstractly, these can all be considered as the users (the experiments, or groups of users within the experiment) expressing a request for a given bandwidth between two points for a given duration of time. The network fabric then grants some allocation to each user, dependent on the sum of all requests and the sum of available resources, and attempts to ensure the requirements are met (either deterministically or statistically). An unresolved question at this time is how to convert the users’ requests into an allocation. Simply put, how do we decide what fraction of a network's bandwidth to allocate to each user when the sum of requests exceeds the available bandwidth? The usual problems of any resourcescheduling system arise here, namely how to ensure the resource is used efficiently and fairly, while still satisfying the needs of the users. Simply fixing quotas on network paths for each user is likely to lead

A Novel Approach to Reduce the Unicast Bandwidth of an IPTV System in a High-Speed Access Network

Directory of Open Access Journals (Sweden)

El Hassane Khabbiza

2017-01-01

Full Text Available Channel change time is a critical quality of experience (QOE metric for IP-based video delivery systems such as Internet Protocol Television (IPTV. An interesting channel change acceleration scheme based on peer-assisted delivery was recently proposed, which consists of deploying one FCC server (Fast Channel Change Server in the IP backbone in order to send the unicast stream to the STB (Set-Top Box before sending the normal multicast stream after each channel change. However, deploying such a solution will cause high bandwidth usage in the network because of the huge unicast traffic sent by the FCC server to the STBs. In this paper, we propose a new solution to reduce the bandwidth occupancy of the unicast traffic, by deploying the FCC server capabilities on the user STB. This means that, after each channel change request, the STB will receive the unicast traffic from another STB instead of the central server. By using this method, the unicast traffic will not pass through the IP network; it will be a peer-to-peer communication via the Access Network only. Extensive simulation results are presented to demonstrate the robustness of our new solution.

Handling high data rate detectors at Diamond Light Source

Science.gov (United States)

Pedersen, U. K.; Rees, N.; Basham, M.; Ferner, F. J. K.

2013-03-01

An increasing number of area detectors, in use at Diamond Light Source, produce high rates of data. In order to capture, store and process this data High Performance Computing (HPC) systems have been implemented. This paper will present the architecture and usage for handling high rate data: detector data capture, large volume storage and parallel processing. The EPICS area Detector frame work has been adopted to abstract the detectors for common tasks including live processing, file format and storage. The chosen data format is HDF5 which provides multidimensional data storage and NeXuS compatibility. The storage system and related computing infrastructure include: a centralised Lustre based parallel file system, a dedicated network and a HPC cluster. A well defined roadmap is in place for the evolution of this to meet demand as the requirements and technology advances. For processing the science data the HPC cluster allow efficient parallel computing, on a mixture of ×86 and GPU processing units. The nature of the Lustre storage system in combination with the parallel HDF5 library allow efficient disk I/O during computation jobs. Software developments, which include utilising optimised parallel file reading for a variety of post processing techniques, are being developed in collaboration as part of the Pan-Data EU Project (www.pan-data.eu). These are particularly applicable to tomographic reconstruction and processing of non crystalline diffraction data.

CHICSi - a compact ultra-high vacuum compatible detector system for nuclear reaction experiments at storage rings. II. Detectors

Energy Technology Data Exchange (ETDEWEB)

Golubev, P.; Avdeichikov, V.; Carlen, L.; Jakobsson, B. E-mail: bo.jakobsson@kosufy.lu.se; Siwek, A.; Veldhuizen, E.J. van; Westerberg, L.; Whitlow, H.J

2003-03-11

We describe the detectors for identification of charged particles and fragments in CHICSi, a large solid angle multi-telescope system mounted inside an ultra-high vacuum (UHV), cluster-jet target chamber. CHICSi performs nuclear reaction experiments at storage rings. The telescopes consist of a first very thin, 10-14 {mu}m Si detector, a second 300 {mu}m (or possibly 500 {mu}m) ion implanted Si detector supplemented by a 6 mm GSO(Ce) scintillator read out by a photodiode (PD) or by a third 300 {mu}m Si detector. The telescopes provide full charge separation up to Z=17 and mass resolution up to A=9 in the energy range 0.7-60A MeV. The thin p-i-n diode detector, etched out from a 280 {mu}m Si wafer, and the GSO/PD detector, both exclusively developed for CHICSi, provide an energy resolution {<=}8%, while the standard 300 {mu}m detectors have {<=}2% energy resolution. Radiation stability of the Si detectors is confirmed up to an integrated flux of 10{sup 10} alpha particles. The GSO detector has 70% light collection efficiency with the optical coupling to the PD a simple open, 0.2 mm, gap. A new method, developed to perform absolute energy calibration for the GSO/PD detector is presented.

CHICSi - a compact ultra-high vacuum compatible detector system for nuclear reaction experiments at storage rings. II. Detectors

International Nuclear Information System (INIS)

Golubev, P.; Avdeichikov, V.; Carlen, L.; Jakobsson, B.; Siwek, A.; Veldhuizen, E.J. van; Westerberg, L.; Whitlow, H.J.

2003-01-01

We describe the detectors for identification of charged particles and fragments in CHICSi, a large solid angle multi-telescope system mounted inside an ultra-high vacuum (UHV), cluster-jet target chamber. CHICSi performs nuclear reaction experiments at storage rings. The telescopes consist of a first very thin, 10-14 μm Si detector, a second 300 μm (or possibly 500 μm) ion implanted Si detector supplemented by a 6 mm GSO(Ce) scintillator read out by a photodiode (PD) or by a third 300 μm Si detector. The telescopes provide full charge separation up to Z=17 and mass resolution up to A=9 in the energy range 0.7-60A MeV. The thin p-i-n diode detector, etched out from a 280 μm Si wafer, and the GSO/PD detector, both exclusively developed for CHICSi, provide an energy resolution ≤8%, while the standard 300 μm detectors have ≤2% energy resolution. Radiation stability of the Si detectors is confirmed up to an integrated flux of 10 10 alpha particles. The GSO detector has 70% light collection efficiency with the optical coupling to the PD a simple open, 0.2 mm, gap. A new method, developed to perform absolute energy calibration for the GSO/PD detector is presented

Towards a large scale high energy cosmic neutrino undersea detector

Energy Technology Data Exchange (ETDEWEB)

Azoulay, R.; Berthier, R. [CEA Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Direction des Sciences de la Matiere; Arpesella, C. [Centre National de la Recherche Scientifique (CNRS), 13 - Marseille (France). Centre de Physique Theorique] [and others

1997-06-01

ANTARES collaboration proposes to study high energy cosmic neutrinos by using a deep sea Cherenkov detector. The potential interest of such a study for astrophysicists and particle physicists is developed. The different origins of cosmic neutrinos are reviewed. In order to observe with relevant statistic the flux of neutrinos from extra-galactic sources, a km-scale detector is necessary. The feasibility of such a detector is studied. A variety of technical problems have been solved. Some of them are standard for particle physicists: choice of photo-multipliers, monitoring, trigger, electronics, data acquisition, detector optimization. Others are more specific of sea science engineering particularly: detector deployment in deep sea, data transmission through optical cables, bio-fouling, effect of sea current. The solutions are presented and the sea engineering part involving detector installation will be tested near French coasts. It is scheduled to build a reduced-scale demonstrator within the next 2 years. (A.C.) 50 refs.

Towards a large scale high energy cosmic neutrino undersea detector

International Nuclear Information System (INIS)

Azoulay, R.; Berthier, R.; Arpesella, C.

1997-06-01

ANTARES collaboration proposes to study high energy cosmic neutrinos by using a deep sea Cherenkov detector. The potential interest of such a study for astrophysicists and particle physicists is developed. The different origins of cosmic neutrinos are reviewed. In order to observe with relevant statistic the flux of neutrinos from extra-galactic sources, a km-scale detector is necessary. The feasibility of such a detector is studied. A variety of technical problems have been solved. Some of them are standard for particle physicists: choice of photo-multipliers, monitoring, trigger, electronics, data acquisition, detector optimization. Others are more specific of sea science engineering particularly: detector deployment in deep sea, data transmission through optical cables, bio-fouling, effect of sea current. The solutions are presented and the sea engineering part involving detector installation will be tested near French coasts. It is scheduled to build a reduced-scale demonstrator within the next 2 years. (A.C.)

A High-Granularity Timing Detector for the Phase-II upgrade of the ATLAS Detector System

CERN Document Server

Agapopoulou, Christina; The ATLAS collaboration

2017-01-01

The expected increase of the particle flux at the high luminosity phase of the LHC with instantaneous luminosities up to L = 7.5 × 10^{34} cm^{−2}s^{−1} will have a severe impact on pile-up. The pile-up is expected to increase on average to 200 interactions per bunch crossing. The reconstruction performance for especially jets and transverse missing energy will be severely degraded in the end-cap and forward region of the ATLAS detector. A High Granularity Timing Detector (HGTD) is proposed in front of the liquid Argon end-cap calorimeters of ATLAS for pile-up mitigation in the offline reconstruction. An additional use of the detector as a luminometer is proposed. This device covers the pseudo-rapidity range of 2.4 to about 4. Four layers of Silicon sensors are foreseen to provide precision timing information with a time resolution of the order of 30 picoseconds per minimum ionizing particle in order to assign the energy deposits in the calorimeter to different proton-proton collision vertices. Each read...

High rate multiplicity detector for relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Beavis, D.; Bennett, M.J.; Carroll, J.B.; Chiba, J.; Chikanian, A.; Crawford, H.J.; Cronqvist, M.; Dardenne, Y.; Debbe, R.; Doke, T.; Engelage, J.; Flores, I.; Greiner, L.; Hayano, R.S.; Hallman, T.J.; Heckman, H.H.; Kashiwagi, T.; Kikuchi, J.; Kumar, B.S.; Kuo, C.; Lindstrom, P.J.; Mitchell, J.W.; Nagamiya, S.; Nagle, J.L.; Pope, J.K.; Stankus, P.; Tanaka, K.H.; Welsh, R.C.; Zhan, W.

1995-01-01

We have constructed and operated a detector to measure the multiplicity of secondary particles produced in nucleus-nucleus collisions in the E878 experiment at the Brookhaven National Laboratory AGS facility. We describe the operation and performance of the detector in a high rate Au beam environment, and interpret the multiplicity data in terms of the impact parameters of the nucleus-nucleus collisions. ((orig.))

High rate multiplicity detector for relativistic heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Beavis, D [Brookhaven National Lab., Upton, NY (United States); Bennett, M J [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Carroll, J B [University of California at Los Angeles, Los Angeles, CA (United States); Chiba, J [KEK National High Energy Physics, Tsukuba (Japan); Chikanian, A [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Crawford, H J [University of California Space Sciences Laboratory, Berkeley, CA (United States); Cronqvist, M [University of California Space Sciences Laboratory, Berkeley, CA (United States); Dardenne, Y [University of California Space Sciences Laboratory, Berkeley, CA (United States); Debbe, R [Brookhaven National Lab., Upton, NY (United States); Doke, T [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Engelage, J [University of California Space Sciences Laboratory, Berkeley, CA (United States); Flores, I [University of California Space Sciences Laboratory, Berkeley, CA (United States); Greiner, L [University of California Space Sciences Laboratory, Berkeley, CA (United States); Hayano, R S [University of Tokyo, Tokyo (Japan); Hallman, T J [University of California at Los Angeles, Los Angeles, CA (United States); Heckman, H H [Lawrence Berkeley Lab., CA (United States); Kashiwagi, T [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kikuchi, J [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kumar, B S [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Kuo, C [University of California Space Sciences Laboratory, Berkeley, CA (United States); Lindstrom, P J [Lawrence Berkeley Lab., CA (United States); Mitchell, J W [Universities Space Research Association/Goddard Space Flight Center, Greenbelt, MD (United States); Nagamiya, S; E878 Collaboration

1995-04-21

We have constructed and operated a detector to measure the multiplicity of secondary particles produced in nucleus-nucleus collisions in the E878 experiment at the Brookhaven National Laboratory AGS facility. We describe the operation and performance of the detector in a high rate Au beam environment, and interpret the multiplicity data in terms of the impact parameters of the nucleus-nucleus collisions. ((orig.)).

A high-resolution multiwire area detector for X-ray scattering

Energy Technology Data Exchange (ETDEWEB)

Faruqi, A R; Andrews, H [Medical Research Council, Cambridge (UK). Lab. of Molecular Biology

1989-11-10

A high-resolution multiwire area detector has been developed for recording X-ray scattering from biological specimens. The detector is 100x100 mm{sup 2} and, under the present operating conditions, has a spatial resolution of about 250 {mu}m in both directions. The detector is set up on a double-mirror focusing camera on a rotating anode X-ray generator and has been used in a number of small-angle experiments, two of which are described in this paper. (orig.).

A time of flight detector for high energy heavy particles

Energy Technology Data Exchange (ETDEWEB)

Fang, Z.; O`Connor, D.J. [Newcastle Univ., NSW (Australia). Dept. of Physics

1993-12-31

As a commonly used method to measure the energy of a particle with known mass, the flight time of the particle travelling over a certain distance is measured. A detector based on this principle is called a time-of-flight (TOF) detector which has attracted interests constantly during the last 15 years. For high energy heavy particle energy detection, TOF detector is an appropriated choice and such a system, developed recently, is described in this paper. 8 refs., 3 figs.

A time of flight detector for high energy heavy particles

Energy Technology Data Exchange (ETDEWEB)

Fang, Z; O` Connor, D J [Newcastle Univ., NSW (Australia). Dept. of Physics

1994-12-31

As a commonly used method to measure the energy of a particle with known mass, the flight time of the particle travelling over a certain distance is measured. A detector based on this principle is called a time-of-flight (TOF) detector which has attracted interests constantly during the last 15 years. For high energy heavy particle energy detection, TOF detector is an appropriated choice and such a system, developed recently, is described in this paper. 8 refs., 3 figs.

Kernel bandwidth estimation for non-parametric density estimation: a comparative study

CSIR Research Space (South Africa)

Van der Walt, CM

2013-12-01

Full Text Available We investigate the performance of conventional bandwidth estimators for non-parametric kernel density estimation on a number of representative pattern-recognition tasks, to gain a better understanding of the behaviour of these estimators in high...

Low mass hybrid pixel detectors for the high luminosity LHC upgrade

Energy Technology Data Exchange (ETDEWEB)

Gonella, Laura

2013-10-15

Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are discussed using the upgrades of the ATLAS pixel detector as a case study.

Low mass hybrid pixel detectors for the high luminosity LHC upgrade

International Nuclear Information System (INIS)

Gonella, Laura

2013-10-01

Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are discussed using the upgrades of the ATLAS pixel detector as a case study.

Comparison of Semidefinite Relaxation Detectors for High-Order Modulation MIMO Systems

Directory of Open Access Journals (Sweden)

Z. Y. Shao

2014-01-01

Full Text Available Multiple-input multiple-output (MIMO system is considered to be one of the key technologies of LTE since it achieves requirements of high throughput and spectral efficiency. The semidefinite relaxation (SDR detection for MIMO systems is an attractive alternative to the optimum maximum likelihood (ML decoding because it is very computationally efficient. We propose a new SDR detector for 256-QAM MIMO system and compare its performance with two other SDR detectors, namely, BC-SDR detector and VA-SDR detector. The tightness and complexity of these three SDR detectors are analyzed. Both theoretical analysis and simulation results demonstrate that the proposed SDR can provide the best BLER performance among the three detectors, while the BC-SDR detector and the VA-SDR detector provide identical BLER performance. Moreover, the BC-SDR has the lowest computational complexity and the VA-SDR has the highest computational complexity, while the proposed SDR is in between.

TPROXY dan FILTERING SEBAGAI METODE OPTIMASI PEMAKAIAN BANDWIDTH INTERNET

Directory of Open Access Journals (Sweden)

Sutiyo Sutiyo

2015-04-01

Full Text Available Until now the use of the internet disuatu agencies viewed from the initial planning, use and care, even long-term planning is still not optimal. The main factor lies in the existing human resources, especially in IT personnel and policy makers who do not understand or do not even know at all how your use of the Internet well, optimal, efficient, particularly associated with the consumption of Internet bandwidth. Internet bandwidth capacity greatly affect the speed of web access or other Internet applications. So we need a plan and maintance necessary to obtain good Internet bandwidth consumption efficiency and guaranteed QoS, such as by utilizing Tproxy and filtering methods. TProxy is a development of which has been patched Squid, a proxy to be able to pass traffic without NAT (Network Access Translation. Fitering a firewall system which is used for filtering data packets that do not want filtered dikendaki or akhirmya able to minimize traffic on bandwidth usage. Tproxy and filtering runs on the Linux platform. Linux distributions are often used to Tproxy is a variant Debian, Centos and then to use Mikrotik Filtering. At the end of each request or query from the client or the response of the proxy server does not have meaningful constraints, the bandwidth between the client and the proxy server does not happen limitation, bandwidth capable of running close to capacity including 10 Mbps Ethernet, 100 Mbps, and even a GPS (full speed.

Influence for high intensity irradiation on characteristics of silicon strip-detectors

International Nuclear Information System (INIS)

Anokhin, I.E.; Pugatch, V.M.; Zinets, O.S.

1995-01-01

Full text: Silicon strip detectors (SSD) are widely used for the coordinate determination of short-range as well as minimum ionizing particles with high spatial resolution. Submicron position sensitivity of strip-detectors for short-range particles has been studied by means of two dimensional analyses of charges collected by neighboring strips as well as by measurement of charge collection times [1]. Silicon strip detectors was also used for testing high energy electron beam [2]. Under large fluences the radiation defects are stored and such characteristics of strip-detectors as an accuracy of the coordinate determination and the registration efficiency are significantly changed. Radiation defects lead to a decrease of the lifetime and mobility of charge carriers and therefore to changes of conditions for the charge collection in detectors. The inhomogeneity in spatial distribution if defects and electrical field plays an important role in the charge collection. In this report the role of the diffusion and drift in the charge collection in silicon strip-detectors under irradiation up to 10 Mrad has been studied. The electric field distribution and its dependence on the radiation dose in the detector have been calculated. It is shown that for particles incident between adjacent strips the coordinate determination precision depends strongly on the detector geometry and the electric field distribution, particularly in the vicinity of strips. Measuring simultaneously the collected charges and collection times on adjacent strips one can essentially improve reliability of the coordinate determination for short-range particles. Usually SSD are fabricated on n-type wafers. It is well known that under high intensity irradiation n-Si material converts into p-Si as far as p-type silicon is more radiative hard than n-type silicon [3] it is reasonable to fabricate SSD using high resistivity p-Si. Characteristics of SSD in basis n-and P-Si have been compared and higher

Optimal Bandwidth Selection in Observed-Score Kernel Equating

Science.gov (United States)

Häggström, Jenny; Wiberg, Marie

2014-01-01

The selection of bandwidth in kernel equating is important because it has a direct impact on the equated test scores. The aim of this article is to examine the use of double smoothing when selecting bandwidths in kernel equating and to compare double smoothing with the commonly used penalty method. This comparison was made using both an equivalent…

Pressure balanced type membrane covered polarographic oxygen detectors for use in high temperature-high pressure water, (1)

International Nuclear Information System (INIS)

Nakayama, Norio; Uchida, Shunsuke

1984-01-01

A pressure balanced type membrane covered polarographic oxygen detector was developed to determine directly oxygen concentrations in high temperature, high pressure water without cooling and pressure reducing procedures. The detector is characterized by the following features: (1) The detector body and the membrane for oxygen penetration are made of heat resistant resin. (2) The whole detector body is contained in a pressure chamber where interior and exterior pressures of the detector are balanced. (3) Thermal expansion of the electrolyte is absorbed by deformation of a diaphragm attached to the detector bottom. (4) The effect of dissolved Ag + on the signal current is eliminated by applying a guard electrode. As a result of performance tests at elevated temperature, it was demonstrated that a linear relationship between oxygen concentration and signal current was obtained up to 285 0 C, which was stabilized by the guard electrode. The minimum O 2 concentration detectable was 0.03ppm (9.4 x 10 -7 mol/kg). (author)

A Study on the Bandwidth Characteristics of Pleated Pneumatic Artificial Muscles

Directory of Open Access Journals (Sweden)

Rino Versluys

2009-01-01

Full Text Available Pleated pneumatic artificial muscles have interesting properties that can be of considerable significance in robotics and automation. With a view to the potential use of pleated pneumatic artificial muscles as actuators for a fatigue test bench (high forces and small displacements, the bandwidth characteristics of a muscle-valve system were investigated. Bandwidth is commonly used for linear systems, as the Bode plot is independent of the amplitude of the input signal. However, due to the non-linear behaviour of pleated pneumatic artificial muscles, the system's gain becomes dependent on the amplitude of the input sine wave. As a result, only one Bode plot is insufficient to clearly describe or identify a non-linear system. In this study, the bandwidth of a muscle-valve system was assessed from two perspectives: a varying amplitude and a varying offset of the input sine wave. A brief introduction to pneumatic artificial muscles is given. The concept of pleated pneumatic artificial muscles is explained. Furthermore, the different test methods and experimental results are presented.

High voltage calibration of the TANSY-KM5 neutron detectors

International Nuclear Information System (INIS)

Grosshoeg, G.; Belle, P. van; Wilson, D.

1996-11-01

We have developed a procedure for the high voltage calibration of the TANSY neutron detectors. The procedure is based on the work done during the construction of the spectrometer. A program is written for the measurement of the sensitivity of the neutron detectors as a function of the high voltage. The data are transferred to a PC for evaluation. We use a Cobalt source for the calibration. With the PC the voltage corresponding to the effective Compton edge is found. The voltage settings for the neutron detectors are calculated and stored in a file suitable for input to a program that is used to control the instrument. A measurement is reported that shows that the reproducibility of the measurement is good. 4 refs

3D detectors with high space and time resolution

Science.gov (United States)

Loi, A.

2018-01-01

For future high luminosity LHC experiments it will be important to develop new detector systems with increased space and time resolution and also better radiation hardness in order to operate in high luminosity environment. A possible technology which could give such performances is 3D silicon detectors. This work explores the possibility of a pixel geometry by designing and simulating different solutions, using Sentaurus Tecnology Computer Aided Design (TCAD) as design and simulation tool, and analysing their performances. A key factor during the selection was the generated electric field and the carrier velocity inside the active area of the pixel.

Stabilized High Power Laser for Advanced Gravitational Wave Detectors

International Nuclear Information System (INIS)

Willke, B; Danzmann, K; Fallnich, C; Frede, M; Heurs, M; King, P; Kracht, D; Kwee, P; Savage, R; Seifert, F; Wilhelm, R

2006-01-01

Second generation gravitational wave detectors require high power lasers with several 100W of output power and with very low temporal and spatial fluctuations. In this paper we discuss possible setups to achieve high laser power and describe a 200W prestabilized laser system (PSL). The PSL noise requirements for advanced gravitational wave detectors will be discussed in general and the stabilization scheme proposed for the Advanced LIGO PSL will be described. Special emphasis will be given to the most demanding power stabilization requirements and new results (RIN ≤ 4x10 -9 /√Hz) will be presented

A high-pressure MWPC detector for crystallography

DEFF Research Database (Denmark)

Ortuno-Prados, F.; Bazzano, A.; Berry, A.

1999-01-01

The application of the Multi-Wire Proportional Counter (MWPC) as a potential detector for protein crystallography and other wide-angle diffraction experiments is presented. Electrostatic problems found with our large area MWPC when operated at high pressure are discussed. We suggest that a solution...

Diamond and silicon pixel detectors in high radiation environments

Energy Technology Data Exchange (ETDEWEB)

Tsung, Jieh-Wen

2012-10-15

Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

Diamond and silicon pixel detectors in high radiation environments

International Nuclear Information System (INIS)

Tsung, Jieh-Wen

2012-10-01

Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10 16 particles per cm 2 , which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10 15 particles per cm 2 .

High-rate performance of muon drift tube detectors

International Nuclear Information System (INIS)

Schwegler, Philipp

2014-01-01

The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are studied. The resolution and efficiency of sMDT chambers at high γ-ray and proton irradiation rates well beyond the ones expected at HL-LHC have been measured and the irradiation effects understood using detailed simulations. The sMDT chambers offer an about an order of magnitude better rate capability and are an ideal replacement for the MDT chambers because of compatibility of services and read-out. The limitations of the sMDT chambers are now in the read-out electronics, taken from the MDT chambers, to which improvements for even higher rate capability are proposed.

A Hybrid OFDM-TDM Architecture with Decentralized Dynamic Bandwidth Allocation for PONs

Directory of Open Access Journals (Sweden)

Taner Cevik

2013-01-01

Full Text Available One of the major challenges of passive optical networks is to achieve a fair arbitration mechanism that will prevent possible collisions from occurring at the upstream channel when multiple users attempt to access the common fiber at the same time. Therefore, in this study we mainly focus on fair bandwidth allocation among users, and present a hybrid Orthogonal Frequency Division Multiplexed/Time Division Multiplexed architecture with a dynamic bandwidth allocation scheme that provides satisfying service qualities to the users depending on their varying bandwidth requirements. Unnecessary delays in centralized schemes occurring during bandwidth assignment stage are eliminated by utilizing a decentralized approach. Instead of sending bandwidth demands to the optical line terminal (OLT which is the only competent authority, each optical network unit (ONU runs the same bandwidth demand determination algorithm. ONUs inform each other via signaling channel about the status of their queues. This information is fed to the bandwidth determination algorithm which is run by each ONU in a distributed manner. Furthermore, Light Load Penalty, which is a phenomenon in optical communications, is mitigated by limiting the amount of bandwidth that an ONU can demand.

A Hybrid OFDM-TDM Architecture with Decentralized Dynamic Bandwidth Allocation for PONs

Science.gov (United States)

Cevik, Taner

2013-01-01

One of the major challenges of passive optical networks is to achieve a fair arbitration mechanism that will prevent possible collisions from occurring at the upstream channel when multiple users attempt to access the common fiber at the same time. Therefore, in this study we mainly focus on fair bandwidth allocation among users, and present a hybrid Orthogonal Frequency Division Multiplexed/Time Division Multiplexed architecture with a dynamic bandwidth allocation scheme that provides satisfying service qualities to the users depending on their varying bandwidth requirements. Unnecessary delays in centralized schemes occurring during bandwidth assignment stage are eliminated by utilizing a decentralized approach. Instead of sending bandwidth demands to the optical line terminal (OLT) which is the only competent authority, each optical network unit (ONU) runs the same bandwidth demand determination algorithm. ONUs inform each other via signaling channel about the status of their queues. This information is fed to the bandwidth determination algorithm which is run by each ONU in a distributed manner. Furthermore, Light Load Penalty, which is a phenomenon in optical communications, is mitigated by limiting the amount of bandwidth that an ONU can demand. PMID:24194684

Admittance detector for high impedance systems: design and applications.

Science.gov (United States)

Zhang, Min; Stamos, Brian N; Dasgupta, Purnendu K

2014-12-02

We describe an admittance detector for high impedance systems (small capillary bore and/or low solution specific conductance). Operation in the low frequency range (≤1 kHz, much lower than most relevant publications) provides optimum response to conductance changes in capillaries ≤20 μm in bore. The detector design was based on studies described in a preceding companion paper ( Zhang, M.; Stamos, B. N.; Amornthammarong, N.; Dasgupta, P. K. Anal. Chem. 2014, 8 , DOI 10.1021/ac503245a.). The highest S/N for detecting 100 μM KCl (5.5 μM peak concentration, ∼0.8 μS/cm) injected into water flowing through a capillary of 7.5 μm inner radius (r) was observed at 500-750 Hz. A low bias current operational amplifier in the transimpedance configuration permitted high gain (1 V/nA) to measure pA-nA level currents in the detection cell. Aside from an oscillator, an offset-capable RMS-DC converter formed the complete detection circuitry. Limits of detection (LODs) of KCl scaled inversely with the capillary cross section and were 2.1 and 0.32 μM injected KCl for r = 1 and 2.5 μm capillaries, respectively. When used as a detector on an r = 8 μm bore poly(methyl methacrylate) capillary in a split effluent stream from a suppressed ion chromatograph, the LOD was 27 nM bromide (Vex 22 V p-p), compared to 14 nM observed with a commercial bipolar pulse macroscale conductivity detector with an actively thermostated cell. We also show applications of the detector in electrophoresis in capillaries with r = 1 and 2.5 μm. Efficient heat dissipation permits high concentrations of the background electrolyte and sensitive detection because of efficient electrostacking.

Passive Mobile Bandwidth Classification Using Short Lived TCP Connections

OpenAIRE

Michelinakis, Foivos; Kreitz, Gunnar; Petrocco, Riccardo; Zhang, Boxun; Widmer, Joerg

2015-01-01

Consumption of multimedia content is moving from a residential environment to mobile phones. Optimizing Quality of Experience—smooth, quick, and high quality playback—is more difficult in this setting, due to the highly dynamic nature of wireless links. A key requirement for achieving this goal is estimating the available bandwidth of mobile devices. Ideally, this should be done quickly and with low overhead. One challenge is that the majority of connections on mobiles are short-lived TCP con...

Bandwidth Estimation in Wireless Lans for Multimedia Streaming Services

Directory of Open Access Journals (Sweden)

Heung Ki Lee

2007-01-01

Full Text Available The popularity of multimedia streaming services via wireless networks presents major challenges in the management of network bandwidth. One challenge is to quickly and precisely estimate the available bandwidth for the decision of streaming rates of layered and scalable multimedia services. Previous studies based on wired networks are too burdensome to be applied to multimedia applications in wireless networks. In this paper, a new method, IdleGap, is suggested to estimate the available bandwidth of a wireless LAN based on the information from a low layer in the protocol stack. We use a network simulation tool, NS-2, to evaluate our new method with various ranges of cross-traffic and observation times. Our simulation results show that IdleGap accurately estimates the available bandwidth for all ranges of cross-traffic (100 Kbps ∼ 1 Mbps with a very short observation time of 10 seconds.

Bandwidth allocation and pricing problem for a duopoly market

Directory of Open Access Journals (Sweden)

You Peng-Sheng

2011-01-01

Full Text Available This research discusses the Internet service provider (ISP bandwidth allocation and pricing problems for a duopoly bandwidth market with two competitive ISPs. According to the contracts between Internet subscribers and ISPs, Internet subscribers can enjoy their services up to their contracted bandwidth limits. However, in reality, many subscribers may experience the facts that their on-line requests are denied or their connection speeds are far below their contracted speed limits. One of the reasons is that ISPs accept too many subscribers as their subscribers. To avoid this problem, ISPs can set limits for their subscribers to enhance their service qualities. This paper develops constrained nonlinear programming to deal with this problem for two competitive ISPs. The condition for reaching the equilibrium between the two competitive firms is derived. The market equilibrium price and bandwidth resource allocations are derived as closed form solutions.

Correlation and image compression for limited-bandwidth CCD.

Energy Technology Data Exchange (ETDEWEB)

Thompson, Douglas G.

2005-07-01

As radars move to Unmanned Aerial Vehicles with limited-bandwidth data downlinks, the amount of data stored and transmitted with each image becomes more significant. This document gives the results of a study to determine the effect of lossy compression in the image magnitude and phase on Coherent Change Detection (CCD). We examine 44 lossy compression types, plus lossless zlib compression, and test each compression method with over 600 CCD image pairs. We also derive theoretical predictions for the correlation for most of these compression schemes, which compare favorably with the experimental results. We recommend image transmission formats for limited-bandwidth programs having various requirements for CCD, including programs which cannot allow performance degradation and those which have stricter bandwidth requirements at the expense of CCD performance.

Large-bandwidth planar photonic crystal waveguides

DEFF Research Database (Denmark)

Søndergaard, Thomas; Lavrinenko, Andrei

2002-01-01

A general design principle is presented for making finite-height photonic crystal waveguides that support leakage-free guidance of light over large frequency intervals. The large bandwidth waveguides are designed by introducing line defects in photonic crystal slabs, where the material in the line...... defect has appropriate dispersion properties relative to the photonic crystal slab material surrounding the line defect. A three-dimensional theoretical analysis is given for large-bandwidth waveguide designs based on a silicon-air photonic crystal slab suspended in air. In one example, the leakage......-free single-mode guidance is found for a large frequency interval covering 60% of the photonic band-gap....

High-Resolution Gamma-Ray Imaging Measurements Using Externally Segmented Germanium Detectors

Science.gov (United States)

Callas, J.; Mahoney, W.; Skelton, R.; Varnell, L.; Wheaton, W.

1994-01-01

Fully two-dimensional gamma-ray imaging with simultaneous high-resolution spectroscopy has been demonstrated using an externally segmented germanium sensor. The system employs a single high-purity coaxial detector with its outer electrode segmented into 5 distinct charge collection regions and a lead coded aperture with a uniformly redundant array (URA) pattern. A series of one-dimensional responses was collected around 511 keV while the system was rotated in steps through 180 degrees. A non-negative, linear least-squares algorithm was then employed to reconstruct a 2-dimensional image. Corrections for multiple scattering in the detector, and the finite distance of source and detector are made in the reconstruction process.

Performance of microstrip and microgap gas detectors at high pressure

International Nuclear Information System (INIS)

Fraga, F.A.F.; Fraga, M.M.F.R.; Marques, R.F.; Margato, L.M.S.; Goncalo, J.R.; Policarpo, A.J.P.L.

1997-01-01

A study of the operation of microstrip and microgap detectors at various gas pressures up to 6 bar with Kr-CO 2 , Xe-CO 2 and Xe-CH 4 is presented. The data were collected with a microstrip (1000 μm pitch) and a microgap (200 μm pitch) detector using a clean chamber and gas system. It is shown that maximum gain is strongly dependent on pressure and gains as high as 9 x 10 3 were obtained with Kr-CO 2 at 6 bar with a MSGC. With the smaller-pitch MGC we could get a gain of 180 with Xe-CH 4 at 6 bar; the typical energy resolution at 22 keV being about 15%. From the present work one can conclude that microstructures can operate at high pressure and that their application in high-efficiency, low-granularity X-ray detectors with an energy range up to a few tens of keV can be seriously considered. (orig.)

Nuclear radiation detectors using high resistivity neutron transmutation doped silicon

International Nuclear Information System (INIS)

Gessner, T.; Irmer, K.

1983-01-01

A method for the production of semiconductor detectors based on high resistivity n-type silicon is described. The n-type silicon is produced by neutron irradiation of p-type silicon. The detectors are produced by planar technique. They are suitable for the spectrometry of alpha particles and for the pulse count measurement of beta particles at room temperature. (author)

High purity liquid phase epitaxial gallium arsenide nuclear radiation detector

International Nuclear Information System (INIS)

Alexiev, D.; Butcher, K.S.A.

1991-11-01

Surface barrier radiation detector made from high purity liquid phase epitaxial gallium arsenide wafers have been operated as X- and γ-ray detectors at various operating temperatures. Low energy isotopes are resolved including 241 Am at 40 deg C. and the higher gamma energies of 235 U at -80 deg C. 15 refs., 1 tab., 6 figs

A track reconstructing low-latency trigger processor for high-energy physics

International Nuclear Information System (INIS)

Cuveland, Jan de

2009-01-01

The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 μs to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbit/s via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's drift chambers based on explicit value comparisons, calculates the momentum of the originating particles from the course of the reconstructed tracks, and finally leads to a trigger decision. The architecture is capable of processing up to 20 000 track segments in less than 2 μs with high detection efficiency and reconstruction precision for high-momentum particles. As a result, this thesis shows how a trigger processor performing complex online track reconstruction within tight real-time requirements can be realized. The presented hardware has been built and is in continuous data taking operation in the ALICE experiment. (orig.)

A track reconstructing low-latency trigger processor for high-energy physics

Energy Technology Data Exchange (ETDEWEB)

Cuveland, Jan de

2009-09-17

The detection and analysis of the large number of particles emerging from high-energy collisions between atomic nuclei is a major challenge in experimental heavy-ion physics. Efficient trigger systems help to focus the analysis on relevant events. A primary objective of the Transition Radiation Detector of the ALICE experiment at the LHC is to trigger on high-momentum electrons. In this thesis, a trigger processor is presented that employs massive parallelism to perform the required online event reconstruction within 2 {mu}s to contribute to the Level-1 trigger decision. Its three-stage hierarchical architecture comprises 109 nodes based on FPGA technology. Ninety processing nodes receive data from the detector front-end at an aggregate net bandwidth of 2.16 Tbit/s via 1080 optical links. Using specifically developed components and interconnections, the system combines high bandwidth with minimum latency. The employed tracking algorithm three-dimensionally reassembles the track segments found in the detector's drift chambers based on explicit value comparisons, calculates the momentum of the originating particles from the course of the reconstructed tracks, and finally leads to a trigger decision. The architecture is capable of processing up to 20 000 track segments in less than 2 {mu}s with high detection efficiency and reconstruction precision for high-momentum particles. As a result, this thesis shows how a trigger processor performing complex online track reconstruction within tight real-time requirements can be realized. The presented hardware has been built and is in continuous data taking operation in the ALICE experiment. (orig.)

Calorimetric low - temperature detectors for high resolution X-ray spectroscopy on stored highly stripped heavy ions

International Nuclear Information System (INIS)

Bleile, A.; Egelhof, P.; Kraft, S.; Meier, H.J.; Shrivastava, A.; Weber, M.; McCammon, D.; Stahle, C.K.

2001-09-01

The accurate determination of the Lamb shift in heavy hydrogen-like ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields, not accessible otherwise. For the investigation of the Lyman-α transitions in 208 Pb 81+ or 238 U 91+ with sufficient accuracy, a high resolution calorimetric detector for hard X-rays (E ≤ 100 keV) is presently being developed. The detector modules consist of arrays of silicon thermistors and of X-ray absorbers made of high-Z material to optimize the absorption efficiency. The detectors are housed in a specially designed 3 He/ 4 He dilution refrigerator with a side arm which fits to the internal target geometry of the storage ring ESR at GSI Darmstadt. The detector performance presently achieved is already close to fulfill the demands of the Lamb shift experiment. For a prototype detector pixel with a 0.2 mm 2 x 47 μm Pb absorber an energy resolution of ΔE FWHM = 65 eV is obtained for 60 keV X-rays. (orig.)

Amplifying modeling for broad bandwidth pulse in Nd:glass based on hybrid-broaden mechanism

International Nuclear Information System (INIS)

Sujingqin; Lanqin, L; Wenyi, W; Feng, J; Xiaofeng, W; Xiaomin, Z; Bin, L

2008-01-01

In this paper, the cross relaxation time is proposed to combine the homogeneous and inhomogeneous broaden mechanism for broad bandwidth pulse amplification model. The corresponding velocity equation, which can describe the response of inverse population on upper and low energy level of gain media to different frequency of pulse, is also put forward. The gain saturation and energy relaxation effect are also included in the velocity equation. Code named CPAP has been developed to simulate the amplifying process of broad bandwidth pulse in multi-pass laser system. The amplifying capability of multi-pass laser system is evaluated and gain narrowing and temporal shape distortion are also investigated when bandwidth of pulse and cross relaxation time of gain media are different. Results can benefit the design of high-energy PW laser system in LFRC, CAEP

Amplifying modeling for broad bandwidth pulse in Nd:glass based on hybrid-broaden mechanism

Energy Technology Data Exchange (ETDEWEB)

Sujingqin; Lanqin, L; Wenyi, W; Feng, J; Xiaofeng, W; Xiaomin, Z [Research Center of Laser Fusion, China Academy of Engineering Physics, P. O. Box 919-988, Mianyang, China, 621900 (China); Bin, L [School of Computer and Communication Engineering, Southwest Jiaotong University, Chengdu. China, 610031 (China)], E-mail: sujingqin@tom.com

2008-05-15

In this paper, the cross relaxation time is proposed to combine the homogeneous and inhomogeneous broaden mechanism for broad bandwidth pulse amplification model. The corresponding velocity equation, which can describe the response of inverse population on upper and low energy level of gain media to different frequency of pulse, is also put forward. The gain saturation and energy relaxation effect are also included in the velocity equation. Code named CPAP has been developed to simulate the amplifying process of broad bandwidth pulse in multi-pass laser system. The amplifying capability of multi-pass laser system is evaluated and gain narrowing and temporal shape distortion are also investigated when bandwidth of pulse and cross relaxation time of gain media are different. Results can benefit the design of high-energy PW laser system in LFRC, CAEP.

TEXAS: a calorimeter-based high-rate detector for the SSC

International Nuclear Information System (INIS)

Alverson, G.; Faissler, W.; Glaubman, M.; Von Goeler, E.; Grimes, A.; Leedomo, I.; Moromisato, J.; Pothier, E.; Reucroft, S.; Saletan, E.; Ayer, F.; Elder, C.; Womble, E.; Sullivan, D.; Bhanot, G.; Mucci, J.; Orr, D.; Reardon, J.; Dautat, H.; McIntyre, R.J.; Dunn, W.L.; Myers, S.K.; O'Foghlundha, F.; Simpkins, J.D.; Yacout, A.M.; Dye, S.; Jones, G.; Klein, S.; Miller, J.P.; Oh, C.; Perlman, D.; Rahman, M.A.; Roberb, B.L.; Stone, J.; Sulak, L.; Worstell, W.; Hecht, M.; Thruston, T.; Hofteizer, J.; Hurlbut, C.; Jaquet, P.; Kamon, T.; Webb, R.; Lane, C.; Murray, J.; Saupp, S.L.; Schulte, T.; Stapleton, J.W.; Winn, D.; Woosley, J.K.

1991-01-01

The conceptual design for a novel SSC detector that focuses on calorimetry is presented. The physics goals include searches for elementary scalars of low mass (M H w ) and high mass (M H >600 GeV), for heavy supersymmetric matter, for compositeness and for strong vector-boson interactions. Examples of the relevant signatures are H→γγ; H→ZZ*; H→lνqanti q, llνν, llqanti q; g tilde g tilde→E T miss +>2 jets; and a jet excess at high p T . These goals may be achieved with high precision, fast compensated and truly hermetic calorimetry, optimized for electrons, photons, and jets. The design allows for total hermeticity to η=5.5 missing energy. All the goals require operation at high luminosity and the additional concerns of γ-γ and jet-jet separation, as well as survival in a high radiation environment, are addressed by an unusually large inner radius of the detector. The detector concept consists of the following few and well defined components: a scintillating fiber tracking system incorporating an imaging preradiator, a projective, finely segmented, thick scintillator calorimeter; and a muon TRD trigger and spectrometer. (orig.)

Signal generation in highly irradiated silicon microstrip detectors for the ATLAS experiment

International Nuclear Information System (INIS)

Ruggiero, Gennaro

2003-01-01

Silicon detectors are the most diffused tracking devices in High Energy Physics (HEP). The reason of such success can be found in the characteristics of the material together with the existing advanced technology for the fabrication of these devices. Nevertheless in many modem HEP experiments the observation of vary rare events require data taking at high luminosity with a consequent extremely intense hadron radiation field that damages the silicon and degrades the performance of these devices. In this thesis work a detailed study of the signal generation in microstrip detectors has been produced with a special care for the ATLAS semiconductor tracker geometry. This has required a development of an appropriate setup to perform measurements with Transient Current/ Charge Technique. This has allowed studying the evolution of the signal in several microstrips detector samples irradiated at fluences covering the range expected in the ATLAS Semiconductor Tracker. For a better understanding of these measurements a powerful software package that simulates the signal generation in these devices has been developed. Moreover in this thesis it has been also shown that the degradation due to radiation in silicon detectors can be strongly reduced if the data taking is done with detectors operated at 130 K. This makes low temperature operation that benefits of the recovery of the charge collection efficiency in highly irradiated silicon detectors (also known as Lazarus effect) an optimal option for future high luminosity experiments. (author)

Variable Bandwidth Analog Channel Filters for Software Defined Radio

NARCIS (Netherlands)

Arkesteijn, V.J.; Klumperink, Eric A.M.; Nauta, Bram

2001-01-01

An important aspect of Software Defined Radio is the ability to define the bandwidth of the filter that selects the desired channel. This paper first explains the importance of channel filtering. Then the advantage of analog channel filtering with a variable bandwidth in a Software Defined Radio is

Breaking Lorentz reciprocity to overcome the time-bandwidth limit in physics and engineering

Science.gov (United States)

Tsakmakidis, K. L.; Shen, L.; Schulz, S. A.; Zheng, X.; Upham, J.; Deng, X.; Altug, H.; Vakakis, A. F.; Boyd, R. W.

2017-06-01

A century-old tenet in physics and engineering asserts that any type of system, having bandwidth Δω, can interact with a wave over only a constrained time period Δt inversely proportional to the bandwidth (Δt·Δω ~ 2π). This law severely limits the generic capabilities of all types of resonant and wave-guiding systems in photonics, cavity quantum electrodynamics and optomechanics, acoustics, continuum mechanics, and atomic and optical physics but is thought to be completely fundamental, arising from basic Fourier reciprocity. We propose that this “fundamental” limit can be overcome in systems where Lorentz reciprocity is broken. As a system becomes more asymmetric in its transport properties, the degree to which the limit can be surpassed becomes greater. By way of example, we theoretically demonstrate how, in an astutely designed magnetized semiconductor heterostructure, the above limit can be exceeded by orders of magnitude by using realistic material parameters. Our findings revise prevailing paradigms for linear, time-invariant resonant systems, challenging the doctrine that high-quality resonances must invariably be narrowband and providing the possibility of developing devices with unprecedentedly high time-bandwidth performance.

Diamond detectors for high energy physics experiments

Science.gov (United States)

Bäni, L.; Alexopoulos, A.; Artuso, M.; Bachmair, F.; Bartosik, M.; Beacham, J.; Beck, H.; Bellini, V.; Belyaev, V.; Bentele, B.; Berdermann, E.; Bergonzo, P.; Bes, A.; Brom, J.-M.; Bruzzi, M.; Cerv, M.; Chiodini, G.; Chren, D.; Cindro, V.; Claus, G.; Collot, J.; Cumalat, J.; Dabrowski, A.; D'Alessandro, R.; Dauvergne, D.; de Boer, W.; Dorfer, C.; Dünser, M.; Eremin, V.; Eusebi, R.; Forcolin, G.; Forneris, J.; Frais-Kölbl, H.; Gallin-Martel, L.; Gallin-Martel, M. L.; Gan, K. K.; Gastal, M.; Giroletti, C.; Goffe, M.; Goldstein, J.; Golubev, A.; Gorišek, A.; Grigoriev, E.; Grosse-Knetter, J.; Grummer, A.; Gui, B.; Guthoff, M.; Haughton, I.; Hiti, B.; Hits, D.; Hoeferkamp, M.; Hofmann, T.; Hosslet, J.; Hostachy, J.-Y.; Hügging, F.; Hutton, C.; Jansen, H.; Janssen, J.; Kagan, H.; Kanxheri, K.; Kasieczka, G.; Kass, R.; Kassel, F.; Kis, M.; Konovalov, V.; Kramberger, G.; Kuleshov, S.; Lacoste, A.; Lagomarsino, S.; Lo Giudice, A.; Lukosi, E.; Maazouzi, C.; Mandic, I.; Mathieu, C.; Menichelli, M.; Mikuž, M.; Morozzi, A.; Moss, J.; Mountain, R.; Murphy, S.; Muškinja, M.; Oh, A.; Oliviero, P.; Passeri, D.; Pernegger, H.; Perrino, R.; Picollo, F.; Pomorski, M.; Potenza, R.; Quadt, A.; Re, A.; Reichmann, M.; Riley, G.; Roe, S.; Sanz, D.; Scaringella, M.; Schaefer, D.; Schmidt, C. J.; Schnetzer, S.; Sciortino, S.; Scorzoni, A.; Seidel, S.; Servoli, L.; Smith, S.; Sopko, B.; Sopko, V.; Spagnolo, S.; Spanier, S.; Stenson, K.; Stone, R.; Sutera, C.; Tannenwald, B.; Taylor, A.; Traeger, M.; Tromson, D.; Trischuk, W.; Tuve, C.; Uplegger, L.; Velthuis, J.; Venturi, N.; Vittone, E.; Wagner, S.; Wallny, R.; Wang, J. C.; Weingarten, J.; Weiss, C.; Wengler, T.; Wermes, N.; Yamouni, M.; Zavrtanik, M.

2018-01-01

Beam test results of the radiation tolerance study of chemical vapour deposition (CVD) diamond against different particle species and energies is presented. We also present beam test results on the independence of signal size on incident particle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition functionality of poly-crystalline CVD diamond 3D devices was demonstrated in beam tests and 3D diamond detectors are shown to be a promising technology for applications in future high luminosity experiments.

Design of the corona current measurement sensor with wide bandwidth under dc ultra-high-voltage environment

International Nuclear Information System (INIS)

Liu, Yingyi; Yuan, Haiwen; Yang, Qinghua; Cui, Yong

2011-01-01

The research in the field of corona discharge, which is one of the key technologies, can help us to realize ultra-high-voltage (UHV) power transmission. This paper proposes a new sampling resistance sensor to measure the dc UHV corona current in a wide band. By designing the structural and distributed parameters of the sensor, the UHV dielectric breakdown performance and the wide-band measuring characteristics of the sensor are satisfied. A high-voltage discharge test shows that the designed sensor can work under a 1200 kV dc environment without the occurrence of corona discharge. A frequency characteristic test shows that the measuring bandwidth of the sensor can be improved from the current 4.5 to 20 MHz. The test results in an actual dc UHV transmission line demonstrate that the sensor can accurately measure the corona current under the dc UHV environment

Bandwidth auction for SVC streaming in dynamic multi-overlay

Science.gov (United States)

Xiong, Yanting; Zou, Junni; Xiong, Hongkai

2010-07-01

In this paper, we study the optimal bandwidth allocation for scalable video coding (SVC) streaming in multiple overlays. We model the whole bandwidth request and distribution process as a set of decentralized auction games between the competing peers. For the upstream peer, a bandwidth allocation mechanism is introduced to maximize the aggregate revenue. For the downstream peer, a dynamic bidding strategy is proposed. It achieves maximum utility and efficient resource usage by collaborating with a content-aware layer dropping/adding strategy. Also, the convergence of the proposed auction games is theoretically proved. Experimental results show that the auction strategies can adapt to dynamic join of competing peers and video layers.

High voltage distribution scheme for large size GEM detector

International Nuclear Information System (INIS)

Saini, J.; Kumar, A.; Dubey, A.K.; Negi, V.S.; Chattopadhyay, S.

2016-01-01

Gas Electron Multiplier (GEM) detectors will be used for Muon tracking in the Compressed Baryonic Matter (CBM) experiment at the Facility for Anti-proton Ion Research (FAIR) at Darmstadt, Germany. The sizes of the detector modules in the Muon chambers are of the order of 1 metre x 0.5 metre. For construction of these chambers, three GEM foils are used per chamber. These foils are made by two layered 50μm thin kapton foil. Each GEM foil has millions of holes on it. In such a large scale manufacturing of the foils, even after stringent quality controls, some of the holes may still have defects or defects might develop over the time with operating conditions. These defects may result in short-circuit of the entire GEM foil. A short even in a single hole will make entire foil un-usable. To reduce such occurrences, high voltage (HV) segmentation within the foils has been introduced. These segments are powered either by individual HV supply per segment or through an active HV distribution to manage such a large number of segments across the foil. Individual supplies apart from being costly, are highly complex to implement. Additionally, CBM will have high intensity of particles bombarding on the detector causing the change of resistive chain current feeding the GEM detector with the variation in the intensity. This leads to voltage fluctuations across the foil resulting in the gain variation with the particle intensity. Hence, a low cost active HV distribution is designed to take care of the above discussed issues

High resolution X radiography imaging detector-micro gap chamber

International Nuclear Information System (INIS)

Long Huqiang; Wang Yun; Xu Dong; Xie Kuanzhong; Bian Jianjiang

2007-01-01

Micro gap chamber (MGC) is a new type of Two-Dimensional position sensitive detector having excellent properties on the space and time resolution, counting rate, 2D compact structure and the flexible of application. It will become a candidate of a new tracking detector for high energy physics experiment. The basic structure and properties of MGC as well as its main research subjects are presented in this paper. Furthermore, the feasibility and validity of utilizing diamond films as the MGC gap material were also discussed in detail. So, a potential radiography imaging detector is provided in order to realize X image and X ray diffraction experiment having very good spatial and time resolution in the 3rd Generation of Synchrotron Radiation Facility. (authors)

A tilted fiber-optic plate coupled CCD detector for high resolution neutron imaging

Energy Technology Data Exchange (ETDEWEB)

Kim, Jongyul; Cho, Gyuseong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Jongyul; Hwy, Limchang; Kim, Taejoo; Lee, Kyehong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Seungwook [Pusan National Univ., Pusan (Korea, Republic of)

2013-05-15

One of these efforts is that a tilted scintillator geometry and lens coupled CCD detector for neutron imaging system were used to improve spatial resolution in one dimension. The increased spatial resolution in one dimension was applied to fuel cell study. However, a lens coupled CCD detector has lower sensitivity than a fiber-optic plate coupled CCD detector due to light loss. In this research, a tilted detector using fiber-optic plate coupled CCD detector was developed to improve resolution and sensitivity. In addition, a tilted detector can prevent an image sensor from direct radiation damage. Neutron imaging has been used for fuel cell study, lithium ion battery study, and many scientific applications. High quality neutron imaging is demanded for more detailed studies of applications, and spatial resolution should be considered to get high quality neutron imaging. Therefore, there were many efforts to improve spatial resolution.

A detector for use in high energy bremsstrahlung shielding studies

International Nuclear Information System (INIS)

Wilson, O.J.; Thomson, J.E.M.

1983-01-01

The design, development and calibration of a detector based on the principle of the Moxon-Rae detector is discussed. It is ideally suited to the measurement of the energy fluence of photons transmitted through a thick shield which has been irradiated with high energy bremsstrahlung. The detection sensitivity is 10 4 to 10 5 times that of the P2 ion chamber

Magnetic Microcalorimeter (MMC) Gamma Detectors with Ultra-High Energy Resolution

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Stephen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2018-01-19

The goal of this LCP is to develop ultra-high resolution gamma detectors based on magnetic microcalorimeters (MMCs) for accurate non-destructive analysis (NDA) of nuclear materials. For highest energy resolution, we will introduce erbium-doped silver (Ag:Er) as a novel sensor material, and implement several geometry and design changes to improve the signal-to-noise ratio. The detector sensitivity will be increased by developing arrays of 32 Ag:Er pixels read out by 16 SQUID preamplifiers, and by developing a cryogenic Compton veto to reduce the spectral background. Since best MMC performance requires detector operation at ~10 mK, we will purchase a dilution refrigerator with a base temperature <10 mK and adapt it for MMC operation. The detector performance will be tested with radioactive sources of interest to the safeguards community.

Development of high pressure-high vacuum-high conductance piston valve for gas-filled radiation detectors

International Nuclear Information System (INIS)

Prasad, D N; Ayyappan, R; Kamble, L P; Singh, J P; Muralikrishna, L V; Alex, M; Balagi, V; Mukhopadhyay, P K

2008-01-01

Gas-filled radiation detectors need gas filling at pressures that range from few cms of mercury to as high as 25kg/cm 2 at room temperature. Before gas-filling these detectors require evacuation to a vacuum of the order of ∼1 x 10 -5 mbar. For these operations of evacuation and gas filling a system consisting of a vacuum pump with a high vacuum gauge, gas cylinder with a pressure gauge and a valve is used. The valve has to meet the three requirements of compatibility with high-pressure and high vacuum and high conductance. A piston valve suitable for the evacuation and gas filling of radiation detectors has been designed and fabricated to meet the above requirements. The stainless steel body (80mmx160mm overall dimensions) valve with a piston arrangement has a 1/2 inch inlet/outlet opening, neoprene/viton O-ring at piston face and diameter for sealing and a knob for opening and closing the valve. The piston movement mechanism is designed to have minimum wear of sealing O-rings. The valve has been hydrostatic pressure tested up to 75bars and has Helium leak rate of less than 9.6x10 -9 m bar ltr/sec in vacuum mode and 2x10 -7 mbar ltr/sec in pressure mode. As compared to a commercial diaphragm valve, which needed 3 hours to evacuate a 7 litre chamber to 2.5x10 -5 mbar, the new valve achieved vacuum 7.4x10 -6 mbar in the same time under the same conditions

Optimal kernel shape and bandwidth for atomistic support of continuum stress

International Nuclear Information System (INIS)

Ulz, Manfred H; Moran, Sean J

2013-01-01

The treatment of atomistic scale interactions via molecular dynamics simulations has recently found favour for multiscale modelling within engineering. The estimation of stress at a continuum point on the atomistic scale requires a pre-defined kernel function. This kernel function derives the stress at a continuum point by averaging the contribution from atoms within a region surrounding the continuum point. This averaging volume, and therefore the associated stress at a continuum point, is highly dependent on the bandwidth and shape of the kernel. In this paper we propose an effective and entirely data-driven strategy for simultaneously computing the optimal shape and bandwidth for the kernel. We thoroughly evaluate our proposed approach on copper using three classical elasticity problems. Our evaluation yields three key findings: firstly, our technique can provide a physically meaningful estimation of kernel bandwidth; secondly, we show that a uniform kernel is preferred, thereby justifying the default selection of this kernel shape in future work; and thirdly, we can reliably estimate both of these attributes in a data-driven manner, obtaining values that lead to an accurate estimation of the stress at a continuum point. (paper)

Optimized high energy resolution in γ-ray spectroscopy with AGATA triple cluster detectors

Energy Technology Data Exchange (ETDEWEB)

Wiens, Andreas

2011-06-20

The AGATA demonstrator consists of five AGATA Triple Cluster (ATC) detectors. Each triple cluster detector contains three asymmetric, 36-fold segmented, encapsulated high purity germanium detectors. The purpose of the demonstrator is to show the feasibility of position-dependent γ-ray detection by means of γ-ray tracking, which is based on pulse shape analysis. The thesis describes the first optimization procedure of the first triple cluster detectors. Here, a high signal quality is mandatory for the energy resolution and the pulse shape analysis. The signal quality was optimized and the energy resolution was improved through the modification of the electronic properties, of the grounding scheme of the detector in particular. The first part of the work was the successful installation of the first four triple cluster detectors at INFN (National Institute of Nuclear Physics) in Legnaro, Italy, in the demonstrator frame prior to the AGATA commissioning experiments and the first physics campaign. The four ATC detectors combine 444 high resolution spectroscopy channels. This number combined with a high density were achieved for the first time for in-beam γ-ray spectroscopy experiments. The high quality of the ATC detectors is characterized by the average energy resolutions achieved for the segments of each crystal in the range of 1.943 and 2.131 keV at a γ-ray energy of 1.33 MeV for the first 12 crystals. The crosstalk level between individual detectors in the ATC is negligible. The crosstalk within one crystal is at a level of 10{sup -3}. In the second part of the work new methods for enhanced energy resolution in highly segmented and position sensitive detectors were developed. The signal-to-noise ratio was improved through averaging of the core and the segment signals, which led to an improvement of the energy resolution of 21% for γ-energies of 60 keV to a FWHM of 870 eV. In combination with crosstalk correction, a clearly improved energy resolution was

A high rate, low noise, x-ray silicon strip detector system

International Nuclear Information System (INIS)

Ludewigt, B.; Jaklevic, J.; Kipnis, I.; Rossington, C.; Spieler, H.

1993-11-01

An x-ray detector system, based on a silicon strip detector wire-bonded to a low noise charge-senstive amplifier integrated circuit, has been developed for synchrotron radiation experiments which require very high count rates and good energy resolution. Noise measurements and x-ray spectra were taken using a 6 mm long, 55 μm pitch strip detector in conjunction with a prototype 16-channel charge-sensitive preamplifier, both fabricated using standard 1.2 μm CMOS technology. The detector system currently achieves an energy resolution of 350 eV FWHM at 5.9 key, 2 μs peaking time, when cooled to -5 degree C

A car-borne highly sensitive near-IR diode-laser methane detector

International Nuclear Information System (INIS)

Berezin, A G; Ershov, Oleg V; Shapovalov, Yu P

2003-01-01

A highly sensitive automated car-borne detector for measuring methane concentration in real time is designed, developed and tested under laboratory and field conditions. Measurements were made with the help of an uncooled tunable near-IR 1.65-μm laser diode. The detector consists of a multipass optical cell with a 45-m long optical path and a base length of 0.5 m. The car-borne detector is intended for monitoring the methane concentration in air from the moving car to reveal the leakage of domestic gas. The sensitivity limit (standard deviation) under field conditions is 1 ppm (20 ppb under laboratory conditions) for a measuring time of 0.4 s. The measuring technique based on the detection of a single methane line ensured a high selectivity of methane detector relative to other gases. The methane detector can be easily modified for measuring other simple-molecule gases (e.g., CO, CO 2 , HF, NO 2 , H 2 O) by replacing the diode laser and varying the parameters of the control program. (special issue devoted to the memory of academician a m prokhorov)

Physical and electrical bandwidths of integrated photodiodes in standard CMOS technology

NARCIS (Netherlands)

Radovanovic, S.; Annema, Anne J.; Nauta, Bram

2003-01-01

The influence of different geometries (layouts) and structures of high-speed photodiodes in fully standard 0.18 μm CMOS technology on their intrinsic (physical) and electrical bandwidths is analyzed. Three photodiode structures are studied: nwell/p-substrate, p+/nwell/p-substrate and p+/nwell. The

Bandwidth tunable microwave photonic filter based on digital and analog modulation

Science.gov (United States)

Zhang, Qi; Zhang, Jie; Li, Qiang; Wang, Yubing; Sun, Xian; Dong, Wei; Zhang, Xindong

2018-05-01

A bandwidth tunable microwave photonic filter based on digital and analog modulation is proposed and experimentally demonstrated. The digital modulation is used to broaden the effective gain spectrum and the analog modulation is to get optical lines. By changing the symbol rate of data pattern, the bandwidth is tunable from 50 MHz to 700 MHz. The interval of optical lines is set according to the bandwidth of gain spectrum which is related to the symbol rate. Several times of bandwidth increase are achieved compared to a single analog modulation and the selectivity of the response is increased by 3.7 dB compared to a single digital modulation.

High P/sub T/ detectors for the SSC

International Nuclear Information System (INIS)

Trilling, G.H.

1987-11-01

Summarized in this report is some of the work done at the recent Workshop on Experiments, Detectors, and Experimental Areas for the Supercollider held at Berkeley. The major goal was to develop an understanding of what complement of detectors would provide the capability for a well-balanced physics program at the SSC. Unlike earlier studies which had emphasized individual components such as tracking, calorimetry, etc., the intention was to focus on complete detectors. The particular detectors discussed in this paper are: the large solenoid detectors, the compact solenoid detectors, the non-magnetic detectors, the dipole detectors and muon detectors. 10 refs., 6 figs., 2 tabs

Detector development for the High Luminosity Large Hadron Collider

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00367854; Gößling, Claus

To maximise the discovery potential of the Large Hadron Collider, it will be upgraded to the High Luminosity Large Hadron Collider in 2024. New detector challenges arise from the higher instantaneous luminosity and the higher particle flux. The new ATLAS Inner Tracker will replace the current tracking detector to be able to cope with these challenges. Many pixel detector technologies exist for particle tracking, but their suitability for the ATLAS Inner Tracker needs to be studied. Active high-voltage CMOS sensors, which are produced in industrialised processes, offer a fast readout and radiation tolerance. In this thesis the HV2FEI4v2 sensor, which is capacitively coupled to the ATLAS Pixel FE-I4 readout chip, is characterised for the usage in the outer layers of the ATLAS Inner Tracker. Key quantities of this prototype module are studied, such as the hit efficiency and the subpixel encoding. The early HV2FEI4v2 prototype shows promising results as a starting point for further module developments. Active CMO...

Glass-embedded two-dimensional silicon photonic crystal devices with a broad bandwidth waveguide and a high quality nanocavity.

Science.gov (United States)

Jeon, Seung-Woo; Han, Jin-Kyu; Song, Bong-Shik; Noda, Susumu

2010-08-30

To enhance the mechanical stability of a two-dimensional photonic crystal slab structure and maintain its excellent performance, we designed a glass-embedded silicon photonic crystal device consisting of a broad bandwidth waveguide and a nanocavity with a high quality (Q) factor, and then fabricated the structure using spin-on glass (SOG). Furthermore, we showed that the refractive index of the SOG could be tuned from 1.37 to 1.57 by varying the curing temperature of the SOG. Finally, we demonstrated a glass-embedded heterostructured cavity with an ultrahigh Q factor of 160,000 by adjusting the refractive index of the SOG.

Bandwidth Dependence of Laser Plasma Instabilities Driven by the Nike KrF Laser

Science.gov (United States)

Weaver, J. L.; Oh, J.; Seely, J.; Kehne, D.; Brown, C. M.; Obenschain, S.; Serlin, V.; Schmitt, A. J.; Phillips, L.; Lehmberg, R. H.; McLean, E.; Manka, C.; Feldman, U.

2011-10-01

The Nike krypton-fluoride (KrF) laser at the Naval Research Laboratory operates in the deep UV (248 nm) and employs beam smoothing by induced spatial incoherence (ISI). In the first ISI studies at longer wavelengths (1054 nm and 527 nm) [Obenschain, PRL 62, 768(1989);Mostovych, PRL, 59, 1193(1987); Peyser, Phys. Fluids B 3, 1479(1991)], stimulated Raman scattering, stimulated Brillouin scattering, and the two plasmon decay instability were reduced when wide bandwidth ISI (δν / ν ~ 0.03-0.19%) pulses irradiated targets at moderate to high intensities (1014-1015W/cm2) . Recent Nike work showed that the threshold for quarter critical instabilities increased with the expected wavelength scaling, without accounting for the large bandwidth (δν ~ 1-3 THz). New experiments will compare laser plasma instabilities (LPI) driven by narrower bandwidth pulses to those observed with the standard operation. The bandwidth of KrF lasers can be reduced by adding narrow filters (etalons or gratings) in the initial stages of the laser. This talk will discuss the method used to narrow the output spectrum of Nike, the laser performance for this new operating mode, and target observations of LPI in planar CH targets. Work supported by DoE/NNSA.

Low-cost bump-bonding processes for high energy physics pixel detectors

CERN Document Server

AUTHOR|(CDS)2069357; Blank, Thomas; Colombo, Fabio; Dierlamm, Alexander Hermann; Husemann, Ulrich; Kudella, Simon; Weber, M

2016-01-01

In the next generation of collider experiments detectors will be challenged by unprecedented particle fluxes. Thus large detector arrays of highly pixelated detectors with minimal dead area will be required at reasonable costs. Bump-bonding of pixel detectors has been shown to be a major cost-driver. KIT is one of five production centers of the CMS barrel pixel detector for the Phase I Upgrade. In this contribution the SnPb bump-bonding process and the production yield is reported. In parallel to the production of the new CMS pixel detector, several alternatives to the expensive photolithography electroplating/electroless metal deposition technologies are developing. Recent progress and challenges faced in the development of bump-bonding technology based on gold-stud bonding by thin (15 μm) gold wire is presented. This technique allows producing metal bumps with diameters down to 30 μm without using photolithography processes, which are typically required to provide suitable under bump metallization. The sh...

High-resolution imaging gamma-ray spectroscopy with externally segmented germanium detectors

Science.gov (United States)

Callas, J. L.; Mahoney, W. A.; Varnell, L. S.; Wheaton, W. A.

1993-01-01

Externally segmented germanium detectors promise a breakthrough in gamma-ray imaging capabilities while retaining the superb energy resolution of germanium spectrometers. An angular resolution of 0.2 deg becomes practical by combining position-sensitive germanium detectors having a segment thickness of a few millimeters with a one-dimensional coded aperture located about a meter from the detectors. Correspondingly higher angular resolutions are possible with larger separations between the detectors and the coded aperture. Two-dimensional images can be obtained by rotating the instrument. Although the basic concept is similar to optical or X-ray coded-aperture imaging techniques, several complicating effects arise because of the penetrating nature of gamma rays. The complications include partial transmission through the coded aperture elements, Compton scattering in the germanium detectors, and high background count rates. Extensive electron-photon Monte Carlo modeling of a realistic detector/coded-aperture/collimator system has been performed. Results show that these complicating effects can be characterized and accounted for with no significant loss in instrument sensitivity.

Development of a high-speed single-photon pixellated detector for visible wavelengths

CERN Document Server

Mac Raighne, Aaron; Mathot, Serge; McPhate, Jason; Vallerga, John; Jarron, Pierre; Brownlee, Colin; O’Shea, Val

2009-01-01

We present the development of a high-speed, single-photon counting, Hybrid Photo Detector (HPD). The HPD consists of a vacuum tube, containing the detector assembly, sealed with a transparent optical input window. Photons incident on the photocathode eject a photoelectron into a large electric field, which accelerates the incident electron onto a silicon detector. The silicon detector is bump bonded to a Medipix readout chip. This set-up allows for the detection and readout of low incident photon intensities at rates that are otherwise unattainable with current camera technology. Reported is the fabrication of the camera that brings together a range of sophisticated design and fabrication techniques and the expected theoretical imaging performance. Applications to cellular and molecular microscopy are also described in which single-photon-counting abilities at high frame rates are crucial

Path connectivity based spectral defragmentation in flexible bandwidth networks.

Science.gov (United States)

Wang, Ying; Zhang, Jie; Zhao, Yongli; Zhang, Jiawei; Zhao, Jie; Wang, Xinbo; Gu, Wanyi

2013-01-28

Optical networks with flexible bandwidth provisioning have become a very promising networking architecture. It enables efficient resource utilization and supports heterogeneous bandwidth demands. In this paper, two novel spectrum defragmentation approaches, i.e. Maximum Path Connectivity (MPC) algorithm and Path Connectivity Triggering (PCT) algorithm, are proposed based on the notion of Path Connectivity, which is defined to represent the maximum variation of node switching ability along the path in flexible bandwidth networks. A cost-performance-ratio based profitability model is given to denote the prons and cons of spectrum defragmentation. We compare these two proposed algorithms with non-defragmentation algorithm in terms of blocking probability. Then we analyze the differences of defragmentation profitability between MPC and PCT algorithms.

Front-end electronics for high rate, position sensitive neutron detectors

CERN Document Server

Yu, B; Harder, J A; Hrisoho, A; Radeka, V; Smith, G C

2002-01-01

Advanced neutron detectors for experiments at new spallation sources will require greater counting rate capabilities than previously attainable. This necessitates careful design of both detector and readout electronics. As part of a new instrument for protein crystallography at LANSCE, we are constructing a detector whose concept was described previously (IEEE Trans. Nucl. Sci. NS-46 (1999) 1916). Here, we describe the signal processing circuit, which is well suited for sup 3 He detectors with a continuous interpolating readout. The circuit is based on standard charge preamplification, transmission of this signal over 20 meters or so, followed by sample and hold using a second order gated baseline restorer. This latter unit provides high rate capability without requiring pole-zero and tail cancellation circuits. There is also provision for gain-adjustment. The circuits are produced in surface mounted technology.

Status report and near future prospects for the gravitational wave detector AURIGA

International Nuclear Information System (INIS)

Zendri, J-P; Baggio, L; Bignotto, M; Bonaldi, M; Cerdonio, M; Conti, L; Rosa, M De; Falferi, P; Fortini, P L; Inguscio, M; Marin, A; Marin, F; Mezzena, R; Ortolan, A; Prodi, G A; Rocco, E; Salemi, F; Soranzo, G; Taffarello, L; Vedovato, G; Vinante, A; Vitale, S

2002-01-01

We describe the experimental efforts to set up the second AURIGA run. Thanks to the upgraded capacitive readout, fully characterized and optimized in a dedicated facility, we predict an improvement in the detector sensitivity and bandwidth by at least one order of magnitude. In the second run, AURIGA will also benefit from newly designed cryogenic mechanical suspensions and the upgraded data acquisition and data analysis

Silicon detectors

International Nuclear Information System (INIS)

Klanner, R.

1984-08-01

The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

A detector for high frequency modulation in auroral particle fluxes

Science.gov (United States)

Spiger, R. J.; Oehme, D.; Loewenstein, R. F.; Murphree, J.; Anderson, H. R.; Anderson, R.

1974-01-01

A high time resolution electron detector has been developed for use in sounding rocket studies of the aurora. The detector is used to look for particle bunching in the range 50 kHz-10 MHz. The design uses an electron multiplier and an onboard frequency spectrum analyzer. By using the onboard analyzer, the data can be transmitted back to ground on a single 93-kHz voltage-controlled oscillator. The detector covers the 50 kHz-10 MHz range six times per second and detects modulation on the order of a new percent of the total electron flux. Spectra are presented for a flight over an auroral arc.

Low level neutron monitoring using high pressure 3He detectors

International Nuclear Information System (INIS)

Pszona, S.

1995-01-01

Three detectors, two spherical proportional counters and an ionisation chamber, all filled with 3 He to pressures of 160 kPa, 325 kPa and 1 MPa respectively have been experimentally studied with respect to their use for low level neutron monitoring. The ambient dose equivalent responses and the energy resolutions of these detectors have been determined. It is shown that spectral analysis of the signals from these detectors not only gives high sensitivity with regard to ambient dose equivalent but also improves the quality of the measurements. A special instrumentation for low level neutron monitoring is described in which a quality control method has been implemented. (Author)

Very broad bandwidth klystron amplifiers

Science.gov (United States)

Faillon, G.; Egloff, G.; Farvet, C.

Large surveillance radars use transmitters at peak power levels of around one MW and average levels of a few kW, and possibly several tens of kW, in S band, or even C band. In general, the amplification stage of these transmitters is a microwave power tube, frequently a klystron. Although designers often turn to klystrons because of their good peak and average power capabilities, they still see them as narrow band amplifiers, undoubtedly because of their resonant cavities which, at first sight, would seem highly selective. But, with the progress of recent years, it has now become quite feasible to use these tubes in installations requiring bandwidths in excess of 10 - 12 percent, and even 15 percent, at 1 MW peak for example, in S-band.

Theoretical study on the ultra-narrow bandwidth tunable atomic filter with electromagnetically induced transparency

Science.gov (United States)

Liu, Yang; Li, Shu-qing; Feng, Zhong-ying; Liu, Xiao-fei; Gao, Jin-yue

2016-12-01

To obtain the weak signal light detection from the high background noise, we present a theoretical study on the ultra-narrow bandwidth tunable atomic filter with electromagnetically induced transparency. In a three-level Λ -type atomic system in the rubidium D1 line, the bandwidth of the EIT atomic filter is narrowed to ~6.5 \\text{MHz} . And the single peak transmission of the filter can be up to 86% . Moreover, the transmission wavelength can be tuned by changing the coupling light frequency. This theoretical scheme can also be applied to other alkali atomic systems.

Preliminary report on the development of a high resolution PET camera using semiconductor detectors

International Nuclear Information System (INIS)

Kikuchi, Yohei; Ishii, Keizo; Yamazaki, Hiromichi; Matsuyama, Shigeo; Yamaguchi, Takashi; Yamamoto, Yusuke; Sato, Takemi; Aoki, Yasushi; Aoki, Kenichi

2005-01-01

We are developing a PET camera using small semiconductor detectors, whose resolution is equivalent to the physical limit of spatial resolution. First, a coincidence system of 16 Schottky CdTe detectors of 0.5 mm width obtained a resolution of <1 mm and it was confirmed that the Schottky CdTe detector is suitable for high resolution PET. Next, the performance of a pair of 32 channel CdTe arrays (1.2 mm width per channel) was investigated for the development of the prototype of high resolution PET. The time resolution between opposing detector pair was 13 ns (FWHM) when high voltage (700 V) was applied. The image of a 0.6 mm diameter point source was obtained in an experiment with opposing detector arrays using four channels, indicating that, a higher resolution can be achieved with the 32 channel CdTe array

Bandwidth-narrowed Bragg gratings inscribed in double-cladding fiber by femtosecond laser.

Science.gov (United States)

Shi, Jiawei; Li, Yuhua; Liu, Shuhui; Wang, Haiyan; Liu, Ningliang; Lu, Peixiang

2011-01-31

Bragg gratings with the bandwidth(FWHM) narrowed up to 79 pm were inscribed in double-cladding fiber with femtosecond radiation and a phase mask followed by an annealing treatment. With the annealing temperature below a critical value, the bandwidth of Bragg gratings induced by Type I-IR and Type II-IR index change was narrowed without the reduction of reflectivity. The bandwidth narrowing is due to the profile transformation of the refractive index modulation caused by the annealing treatment. This mechanism was verified by comparing bandwidth narrowing processes of FBGs written with different power densities.

Low mass hybrid pixel detectors for the high luminosity LHC upgrade

CERN Document Server

Gonella, Laura; Desch, Klaus

2013-11-11

Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are dis...

MPTCP Tunnel: An Architecture for Aggregating Bandwidth of Heterogeneous Access Networks

Directory of Open Access Journals (Sweden)

Xiaolan Liu

2018-01-01

Full Text Available Fixed and cellular networks are two typical access networks provided by operators. Fixed access network is widely employed; nevertheless, its bandwidth is sometimes not sufficient enough to meet user bandwidth requirements. Meanwhile, cellular access network owns unique advantages of wider coverage, faster increasing link speed, more flexible deployment, and so forth. Therefore, it is attractive for operators to mitigate the bandwidth shortage by bundling these two. Actually, there have been existing schemes proposed to aggregate the bandwidth of two access networks, whereas they all have their own problems, like packet reordering or extra latency overhead. To address this problem, we design new architecture, MPTCP Tunnel, to aggregate the bandwidth of multiple heterogeneous access networks from the perspective of operators. MPTCP Tunnel uses MPTCP, which solves the reordering problem essentially, to bundle multiple access networks. Besides, MPTCP Tunnel sets up only one MPTCP connection at play which adapts itself to multiple traffic types and TCP flows. Furthermore, MPTCP Tunnel forwards intact IP packets through access networks, maintaining the end-to-end TCP semantics. Experimental results manifest that MPTCP Tunnel can efficiently aggregate the bandwidth of multiple access networks and is more adaptable to the increasing heterogeneity of access networks than existing mechanisms.

A bandwidth independent linear method for detection of carrier envelope phase drift

International Nuclear Information System (INIS)

Goerbe, M.

2006-01-01

Complete test of publication follows. Most of the femtosecond-scale physical phenomena can be experimentally investigated by using carrier-envelope phase (CEP) stabilized laser pulses only. The usual method of CEP stabilization requires laser pulses with a bandwidth of one octave broad at least. If the spectrum of the fundamental pulse itself is not sufficiently broad, then its bandwidth has to be broadened by use of any nonlinear method. Spectrally and spatially resolved interferometry (SSRI) has been proven to be a powerful technique for dispersion measurement of various materials and optical elements. It typically consists of a two-beam interferometer equipped with an imaging spectrograph. The interference pattern is imaged onto the input slit of the spectrograph, so that spatially (along the slit) and spectrally resolved interference fringes are formed on the 2D detector (CCD camera) inserted at the output plane of the spectrograph. In this paper we show that the visibility of the spectrally and spatially resolved interference fringes depends strongly on the CEP drift of subsequent pulses from a pulse train. When the pulses are CEP stabilized then the visibility has a definite extremum. To introduce the operation principle, let's assume a black box in the sample are of the interferometer illuminated by train of CEP-stabilized laser pulses. This imaginary black box would change only the CEP of the subsequent pulses by Δ ψ but leaves their dispersion relative to the reference pulse, i.e. the pulse propagating in the other arm of the interferometer, unchanged. The spatial position of the interference fringes depends on Δ ψ . If the subsequent fringes are formed by pulses with different CEP, the spatial position of each interference fringe changes. The detector, i.e. the CCD chip of the imaging spectrograph is slow, so that it actually captures many subsequent interference patterns, on top of each other. As a result, the visibility of the resulted and captured

Digital approach to high-resolution pulse processing for semiconductor detectors

International Nuclear Information System (INIS)

Georgiev, A.; Buchner, A.; Gast, W.; Lieder, R.M.

1992-01-01

A new design philosophy for processing signals produced by high resolution, large volume semiconductor detectors is described. These detectors, to be used in the next generation of spectrometer arrays for nuclear research (i.e. EUROBALL, etc.), present a set of problems like resolution degradation due to charge trapping and ballistic defect effects, low resolution at a high count rate, poor long term stability, etc. To solve these problems, a new design approach has been developed, including reconstruction of the event charge, providing a pure triangular residual function, and suppressing low frequency noise. 5 refs., 4 figs

Digital approach to high-resolution pulse processing for semiconductor detectors

Energy Technology Data Exchange (ETDEWEB)

Georgiev, A [Sofia Univ. (Bulgaria); Buchner, A [Forschungszentrum Rossendorf (Germany); Gast, W; Lieder, R M [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Stein, J [Target System Electronic GmbH, Solingen, (Germany)

1992-08-01

A new design philosophy for processing signals produced by high resolution, large volume semiconductor detectors is described. These detectors, to be used in the next generation of spectrometer arrays for nuclear research (i.e. EUROBALL, etc.), present a set of problems like resolution degradation due to charge trapping and ballistic defect effects, low resolution at a high count rate, poor long term stability, etc. To solve these problems, a new design approach has been developed, including reconstruction of the event charge, providing a pure triangular residual function, and suppressing low frequency noise. 5 refs., 4 figs.

Nanosecond X-ray detector based on high resistivity ZnO single crystal semiconductor

Energy Technology Data Exchange (ETDEWEB)

Zhao, Xiaolong; He, Yongning, E-mail: yongning@mail.xjtu.edu.cn; Peng, Wenbo; Huang, Zhiyong; Qi, Xiaomeng; Pan, Zijian; Zhang, Wenting [School of Electronic and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Liang; Liu, Jinliang; Zhang, Zhongbing; Ouyang, Xiaoping [Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

2016-04-25

The pulse radiation detectors are sorely needed in the fields of nuclear reaction monitoring, material analysis, astronomy study, spacecraft navigation, and space communication. In this work, we demonstrate a nanosecond X-ray detector based on ZnO single crystal semiconductor, which emerges as a promising compound-semiconductor radiation detection material for its high radiation tolerance and advanced large-size bulk crystal growth technique. The resistivity of the ZnO single crystal is as high as 10{sup 13} Ω cm due to the compensation of the donor defects (V{sub O}) and acceptor defects (V{sub Zn} and O{sub i}) after high temperature annealing in oxygen. The photoconductive X-ray detector was fabricated using the high resistivity ZnO single crystal. The rise time and fall time of the detector to a 10 ps pulse electron beam are 0.8 ns and 3.3 ns, respectively, indicating great potential for ultrafast X-ray detection applications.

An Application-Level QoS Control Method Based on Local Bandwidth Scheduling

Directory of Open Access Journals (Sweden)

Yong Wang

2018-01-01

Full Text Available Quality of service (QoS is an important performance indicator for Web applications and bandwidth is a key factor affecting QoS. Current methods use network protocols or ports to schedule bandwidth, which require tedious manual configurations or modifications of the underlying network. Some applications use dynamic ports and the traditional port-based bandwidth control methods cannot deal with them. A new QoS control method based on local bandwidth scheduling is proposed, which can schedule bandwidth at application level in a user-transparent way and it does not require tedious manual configurations. Experimental results indicate that the new method can effectively improve the QoS for applications, and it can be easily integrated into current Web applications without the need to modify the underlying network.

High-resolution ion-implanted silicon detectors

International Nuclear Information System (INIS)

von Borany, J.; Schmidt, B.

1985-01-01

An account is given of the properties of silicon detectors developed at the Central Institute of Nuclear Research of the Academy of Sciences of the German Democratic Republic (Rossendorf) and made by a special planar technology using ion implantation, anodic oxidation, thermal oxidation in an oxygen atmosphere containing HCl, and annealing by pulses of 10--20 msec duration. The resolution for α particles of 5.5 MeV energy was 11.2 keV (active area A 2 ). The detectors were characterized by a low intrinsic noise (< or =5 keV), so that they could be used for spectrometry of low-energy electrons (E/sub e/< or =250 keV). In a certain range of energies (E/sub x/ = 15--60 keV) it was possible to use these detectors for spectrometry of x rays at room temperature. Examples and results of applications of detectors in radiation chemistry (investigations of backscattering of particles and nuclear reaction spectroscopy) are given. The feasibility of annealing of radiation defects in such detectors after irradiation with a large dose of charged particles is considered

Commissioning and first results from the CMS phase-1 upgrade pixel detector

CERN Document Server

Sonneveld, Jorine Mirjam

2017-01-01

The phase~1 upgrade of the CMS pixel detector has been designed to maintain the tracking performance at instantaneous luminosities of $2 \\times 10^{34} \\mathrm{~cm}^{-2} \\mathrm{~s}^{-1}$. Both barrel and endcap disk systems now feature one extra layer (4 barrel layers and 3 endcap disks), and a digital readout that provides a large enough bandwidth to read out its 124M pixel channels (87.7 percent more pixels compared to the previous system). The backend control and readout systems have been upgraded accordingly from VME-based to micro-TCA-based ones. The detector is now also fitted with a bi-phase CO$_2$ cooling system that reduces the material budget in the tracking region. The detector has been installed inside CMS at the start of 2017 and is now taking data. These proceedings discuss experiences in the commissioning and operation of the CMS phase~1 pixel detector. The first results from the CMS phase~1 pixel detector with this year's LHC proton-proton collision data are presented. ...

Pushing the Envelope: Ship to Shore Events and High-Bandwidth Telepresence Engages Scientists and the Public

Science.gov (United States)

Cooper, S. K.; Coleman, D. F.; Fisher, A. T.; Livelybrooks, D.; Mulder, G.

2013-12-01

Since 2009, the drillship JOIDES Resolution has engaged in an extensive program of live ship-to-shore events during its two-month scientific expeditions using a range of software applications and formats. The University of Rhode Island's Inner Space Center has utilized a high bandwidth 'telepresence' from ships such as the Ocean Exploration Trust's E/V Nautilus and the NOAA Ship Okeanos Explorer, to bring live feeds from underwater exploration vehicles directly into museums, aquaria, science centers, boys and girls clubs, and K-16 classrooms. Both of these strategies have employed close partnerships between scientists and educators to bring cutting edge research and the excitement of exploration and discovery directly to the public in close to real time, but telepresence provides unique opportunities. Participants have been able to experience, live, launches of remotely operated vehicle systems including Jason/Medea on R/V Atlantis and Hercules/Argus on Nautilus, see scientific samples come up on deck for the very first time, observe previously-undiscovered shipwrecks at the same time as those on ship, and watch amazing deep sea creatures swim past deep water cameras. There are many benefits from high-bandwidth telepresence, including improved quality of images, video, and sound; the ability to move large data sets and files between ship and shore, allowing collaboration among individuals who are not on the ship; the ability to stage spontaneous "web events" among scientific, educational, and technical personnel at essentially any time; and more intensive interactions through use of social media, such as blogging, posting of multimedia products, and frequent question/answer sessions. These telepresence-enhanced activities assist the public in understanding the significance and excitement of these discoveries, the challenges of working in the deep sea, and the true nature of scientific processes. These interactions have significant impacts on their audiences, and

High-Dose Neutron Detector Development Using ¹⁰B Coated Cells

Energy Technology Data Exchange (ETDEWEB)

Menlove, Howard Olsen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-11-08

During FY16 the boron-lined parallel-plate technology was optimized to fully benefit from its fast timing characteristics in order to enhance its high count rate capability. To facilitate high count rate capability, a novel fast amplifier with timing and operating properties matched to the detector characteristics was developed and implemented in the 8” boron plate detector that was purchased from PDT. Each of the 6 sealed-cells was connected to a fast amplifier with corresponding List mode readout from each amplifier. The FY16 work focused on improvements in the boron-10 coating materials and procedures at PDT to significantly improve the neutron detection efficiency. An improvement in the efficiency of a factor of 1.5 was achieved without increasing the metal backing area for the boron coating. This improvement has allowed us to operate the detector in gamma-ray backgrounds that are four orders of magnitude higher than was previously possible while maintaining a relatively high counting efficiency for neutrons. This improvement in the gamma-ray rejection is a key factor in the development of the high dose neutron detector.

The BaBar LST Detector High Voltage System: Design And Implementation

International Nuclear Information System (INIS)

Benelli, G.; Honscheid, K.; Lewis, E.A.; Regensburger, J.J.; Smith, D.S.; Ohio State U.

2006-01-01

In 2004, the first two sextants of the new Limited Streamer Tube (LST) detector were installed in the BABAR experiment to replace the ageing Resistive Plate Chambers (RPCs) as active detectors for the BABAR Instrumented Flux Return (IFR) muon system. Each streamer tube of the new detector consists of 8 cells. The cell walls are coated with graphite paint and a 100 (micro)m wire forms the anode. These wires are coupled in pairs inside the tubes resulting in 4 independent two-cell segments per LST. High voltage (HV) is applied to the 4 segments through a custom connector that also provides the decoupling capacitor to pick up the detector signals from the anode wires. The BABAR LST detector is operated at 5.5 kV. The high voltage system for the LST detector was designed and built at The Ohio State University (OSU HVPS). Each of the 25 supplies built for BaBar provides 80 output channels with individual current monitoring and overcurrent protection. For each group of 20 channels the HV can be adjusted between 0 and 6 kV. A 4-fold fan-out is integrated in the power supplies to provide a total of 320 outputs. The power supplies are controlled through built-in CANbus and Ethernet (TCP/IP) interfaces. In this presentation we will discuss the design and novel features of the OSU HVPS system and its integration into the BABAR EPICS detector control framework. Experience with the supplies operation during the LST extensive quality control program and their performance during the initial data taking period will be discussed

Development and features of an X-ray detector with high spatial resolution

International Nuclear Information System (INIS)

Hartmann, H.

1979-09-01

A laboratory model of an X-ray detector with high spatial resolution was developed and constructed. It has no spectral resolution, but a local resolution of 20 μm which is about ten times as high as that of position-sensitive proportional counters and satisfies the requirements of the very best Wolter telescopes with regard to spatial resolution. The detector will be used for laboratory tests of the 80 cm Wolter telescope which is being developed for Spacelab flights. The theory of the wire grid detector and the physics of the photoelectric effect has been developed, and model calculations and numerical calculations have been carried out. (orig./WB) [de

Charge collection performance of a segmented planar high-purity germanium detector

Energy Technology Data Exchange (ETDEWEB)

Cooper, R.J. [Department of Physics, The University of Liverpool, Oliver Lodge Laboratory, Liverpool Merseyside L69 7ZE (United Kingdom)], E-mail: R.Cooper@liverpool.ac.uk; Boston, A.J.; Boston, H.C.; Cresswell, J.R.; Grint, A.N.; Harkness, L.J.; Nolan, P.J.; Oxley, D.C.; Scraggs, D.P. [Department of Physics, The University of Liverpool, Oliver Lodge Laboratory, Liverpool Merseyside L69 7ZE (United Kingdom); Lazarus, I.; Simpson, J. [STFC Daresbury Laboratory, Warrington, Cheshire WA4 4AD (United Kingdom); Dobson, J. [Rosemere Cancer Centre, Royal Preston Hospital, Preston PR2 9HT (United Kingdom)

2008-10-01

High-precision scans of a segmented planar high-purity germanium (HPGe) detector have been performed with a range of finely collimated gamma ray beams allowing the response as a function of gamma ray interaction position to be quantified. This has allowed the development of parametric pulse shape analysis (PSA) techniques and algorithms for the correction of imperfections in performance. In this paper we report on the performance of this detector, designed for use in a positron emission tomography (PET) development system.

Hexagonal boron nitride neutron detectors with high detection efficiencies

Science.gov (United States)

Maity, A.; Grenadier, S. J.; Li, J.; Lin, J. Y.; Jiang, H. X.

2018-01-01

Neutron detectors fabricated from 10B enriched hexagonal boron nitride (h-10BN or h-BN) epilayers have demonstrated the highest thermal neutron detection efficiency among solid-state neutron detectors to date at about 53%. In this work, photoconductive-like vertical detectors with a detection area of 1 × 1 mm2 were fabricated from 50 μm thick free-standing h-BN epilayers using Ni/Au and Ti/Al bilayers as ohmic contacts. Leakage currents, mobility-lifetime (μτ) products under UV photoexcitation, and neutron detection efficiencies have been measured for a total of 16 different device configurations. The results have unambiguously identified that detectors incorporating the Ni/Au bilayer on both surfaces as ohmic contacts and using the negatively biased top surface for neutron irradiation are the most desired device configurations. It was noted that high growth temperatures of h-10BN epilayers on sapphire substrates tend to yield a higher concentration of oxygen impurities near the bottom surface, leading to a better device performance by the chosen top surface for irradiation than by the bottom. Preferential scattering of oxygen donors tends to reduce the mobility of holes more than that of electrons, making the biasing scheme with the ability of rapidly extracting holes at the irradiated surface while leaving the electrons to travel a large average distance inside the detector at a preferred choice. When measured against a calibrated 6LiF filled micro-structured semiconductor neutron detector, it was shown that the optimized configuration has pushed the detection efficiency of h-BN neutron detectors to 58%. These detailed studies also provided a better understanding of growth-mediated impurities in h-BN epilayers and their effects on the charge collection and neutron detection efficiencies.

Analytical optimization of active bandwidth and quality factor for TOCSY experiments in NMR spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Coote, Paul, E-mail: paul-coote@hms.harvard.edu [Harvard Medical School (United States); Bermel, Wolfgang [Bruker BioSpin GmbH (Germany); Wagner, Gerhard; Arthanari, Haribabu, E-mail: hari@hms.harvard.edu [Harvard Medical School (United States)

2016-09-15

Active bandwidth and global quality factor are the two main metrics used to quantitatively compare the performance of TOCSY mixing sequences. Active bandwidth refers to the spectral region over which at least 50 % of the magnetization is transferred via a coupling. Global quality factor scores mixing sequences according to the worst-case transfer over a range of possible mixing times and chemical shifts. Both metrics reward high transfer efficiency away from the main diagonal of a two-dimensional spectrum. They can therefore be used to design mixing sequences that will function favorably in experiments. Here, we develop optimization methods tailored to these two metrics, including precise control of off-diagonal cross peak buildup rates. These methods produce square shaped transfer efficiency profiles, directly matching the desirable properties that the metrics are intended to measure. The optimization methods are analytical, rather than numerical. The two resultant shaped pulses have significantly higher active bandwidth and quality factor, respectively, than all other known sequences. They are therefore highly suitable for use in NMR spectroscopy. We include experimental verification of these improved waveforms on small molecule and protein samples.

Prototyping of petalets for the Phase-II upgrade of the silicon strip tracking detector of the ATLAS experiment

Science.gov (United States)

Kuehn, S.; Benítez, V.; Fernández-Tejero, J.; Fleta, C.; Lozano, M.; Ullán, M.; Lacker, H.; Rehnisch, L.; Sperlich, D.; Ariza, D.; Bloch, I.; Díez, S.; Gregor, I.; Keller, J.; Lohwasser, K.; Poley, L.; Prahl, V.; Zakharchuk, N.; Hauser, M.; Jakobs, K.; Mahboubi, K.; Mori, R.; Parzefall, U.; Bernabéu, J.; Lacasta, C.; Marco-Hernandez, R.; Rodriguez Rodriguez, D.; Santoyo, D.; Solaz Contell, C.; Soldevila Serrano, U.; Affolder, T.; Greenall, A.; Gallop, B.; Phillips, P. W.; Cindro, V.

2018-03-01

In the high luminosity era of the Large Hadron Collider, the instantaneous luminosity is expected to reach unprecedented values, resulting in about 200 proton-proton interactions in a typical bunch crossing. To cope with the resultant increase in occupancy, bandwidth and radiation damage, the ATLAS Inner Detector will be replaced by an all-silicon system, the Inner Tracker (ITk). The ITk consists of a silicon pixel and a strip detector and exploits the concept of modularity. Prototyping and testing of various strip detector components has been carried out. This paper presents the developments and results obtained with reduced-size structures equivalent to those foreseen to be used in the forward region of the silicon strip detector. Referred to as petalets, these structures are built around a composite sandwich with embedded cooling pipes and electrical tapes for routing the signals and power. Detector modules built using electronic flex boards and silicon strip sensors are glued on both the front and back side surfaces of the carbon structure. Details are given on the assembly, testing and evaluation of several petalets. Measurement results of both mechanical and electrical quantities are shown. Moreover, an outlook is given for improved prototyping plans for large structures.

Design of ultrathin dual-resonant reflective polarization converter with customized bandwidths

Science.gov (United States)

Kundu, Debidas; Mohan, Akhilesh; Chakrabarty, Ajay

2017-10-01

In this paper, an ultrathin dual-resonant reflective polarization converter is proposed to obtain customized bandwidths using precise space-filling technique to its top geometry. The unit cell of the dual-resonant prototype consists of conductive square ring with two diagonally arranged slits, supported by metal-backed thin dielectric layer. It offers two narrow bands with fractional bandwidths of 3.98 and 6.65% and polarization conversion ratio (PCR) of 97.16 and 98.87% at 4.52 and 6.97 GHz, respectively. The resonances are brought in proximity to each other by changing the length of surface current paths of the two resonances. By virtue of this mechanism, two polarization converters with two different types of bandwidths are obtained. One polarization converter produces a full-width at half-maxima PCR bandwidth of 34%, whereas another polarization converter produces a 90% PCR bandwidth of 19%. All the proposed polarization converters are insensitive to wide variations of incident angle for both TE- and TM-polarized incident waves. Measured results show good agreement with the numerically simulated results.

Detectors and signal processing for high-energy physics

International Nuclear Information System (INIS)

Rehak, P.

1981-01-01

Basic principles of the particle detection and signal processing for high-energy physics experiments are presented. It is shown that the optimum performance of a properly designed detector system is not limited by incidental imperfections, but solely by more fundamental limitations imposed by the quantum nature and statistical behavior of matter. The noise sources connected with the detection and signal processing are studied. The concepts of optimal filtering and optimal detector/amplifying device matching are introduced. Signal processing for a liquid argon calorimeter is analyzed in some detail. The position detection in gas counters is studied. Resolution in drift chambers for the drift coordinate measurement as well as the second coordinate measurement is discussed

Optical slotted circuit switched network: a bandwidth efficient alternative to wavelength-routed network

Science.gov (United States)

Li, Yan; Collier, Martin

2007-11-01

Wavelength-routed networks have received enormous attention due to the fact that they are relatively simple to implement and implicitly offer Quality of Service (QoS) guarantees. However, they suffer from a bandwidth inefficiency problem and require complex Routing and Wavelength Assignment (RWA). Most attempts to address the above issues exploit the joint use of WDM and TDM technologies. The resultant TDM-based wavelength-routed networks partition the wavelength bandwidth into fixed-length time slots organized as a fixed-length frame. Multiple connections can thus time-share a wavelength and the grooming of their traffic leads to better bandwidth utilization. The capability of switching in both wavelength and time domains in such networks also mitigates the RWA problem. However, TMD-based wavelength-routed networks work in synchronous mode and strict synchronization among all network nodes is required. Global synchronization for all-optical networks which operate at extremely high speed is technically challenging, and deploying an optical synchronizer for each wavelength involves considerable cost. An Optical Slotted Circuit Switching (OSCS) architecture is proposed in this paper. In an OSCS network, slotted circuits are created to better utilize the wavelength bandwidth than in classic wavelength-routed networks. The operation of the protocol is such as to avoid the need for global synchronization required by TDM-based wavelength-routed networks.

The gravitational wave detector NAUTILUS operating at T = 0.1 K

International Nuclear Information System (INIS)

Astone, P.; Bassan, M.; Bonifazi, P.

1997-02-01

They report on the ultralow-temperature resonant-mass gravitational-wave detector NAUTILUS operating at the Frascati INFN Laboratories. The present aim of this detector is to achieve a sensitivity sufficient to detect bursts of gravitational radiation from sources located in our Galaxy and in the local group. Progress in transducer technology is likely to lead to sensitivities that will enable them to observe events from sources as far away as the Virgo cluster of galaxies. They describe the cryogenic apparatus, readout system cosmic-ray veto system, and give first results obtained during one year of continuous operation at T = 0.1 K. In particular the Brownian noise of the detector at T = 0.1 K was measured. The measured strain sensitivity was h-tilde ∼ 6 10 -22 Hz -1/2 at the frequencies of the two modes, 908 Hz and 924 Hz, with bandwidths of about 1 Hz

FPGA based compute nodes for high level triggering in PANDA

International Nuclear Information System (INIS)

Kuehn, W; Gilardi, C; Kirschner, D; Lang, J; Lange, S; Liu, M; Perez, T; Yang, S; Schmitt, L; Jin, D; Li, L; Liu, Z; Lu, Y; Wang, Q; Wei, S; Xu, H; Zhao, D; Korcyl, K; Otwinowski, J T; Salabura, P

2008-01-01

PANDA is a new universal detector for antiproton physics at the HESR facility at FAIR/GSI. The PANDA data acquisition system has to handle interaction rates of the order of 10 7 /s and data rates of several 100 Gb/s. FPGA based compute nodes with multi-Gb/s bandwidth capability using the ATCA architecture are designed to handle tasks such as event building, feature extraction and high level trigger processing. Data connectivity is provided via optical links as well as multiple Gb Ethernet ports. The boards will support trigger algorithms such us pattern recognition for RICH detectors, EM shower analysis, fast tracking algorithms and global event characterization. Besides VHDL, high level C-like hardware description languages will be considered to implement the firmware

Characterization of segmented large volume, high purity germanium detectors

International Nuclear Information System (INIS)

Bruyneel, B.

2006-01-01

γ-ray tracking in future HPGe arrays like AGATA will rely on pulse shape analysis (PSA) of multiple γ-interactions. For this purpose, a simple and fast procedure was developed which enabled the first full characterization of a segmented large volume HPGe detector. An analytical model for the hole mobility in a Ge crystal lattice was developed to describe the hole drift anisotropy with experimental velocity values along the crystal axis as parameters. The new model is based on the drifted Maxwellian hole distribution in Ge. It is verified by reproducing successfully experimental longitudinal hole anisotropy data. A comparison between electron and hole mobility shows large differences for the longitudinal and tangential velocity anisotropy as a function of the electrical field orientation. Measurements on a 12 fold segmented, n-type, large volume, irregular shaped HPGe detector were performed in order to determine the parameters of anisotropic mobility for electrons and holes as charge carriers created by γ-ray interactions. To characterize the electron mobility the complete outer detector surface was scanned in small steps employing photopeak interactions at 60 keV. A precise measurement of the hole drift anisotropy was performed with 356 keV rays. The drift velocity anisotropy and crystal geometry cause considerable rise time differences in pulse shapes depending on the position of the spatial charge carrier creation. Pulse shapes of direct and transient signals are reproduced by weighting potential calculations with high precision. The measured angular dependence of rise times is caused by the anisotropic mobility, crystal geometry, changing field strength and space charge effects. Preamplified signals were processed employing digital spectroscopy electronics. Response functions, crosstalk contributions and averaging procedures were taken into account implying novel methods due to the segmentation of the Ge-crystal and the digital electronics. The results are

Characterization of segmented large volume, high purity germanium detectors

Energy Technology Data Exchange (ETDEWEB)

Bruyneel, B. [Koeln Univ. (Germany). Inst. fuer Kernphysik

2006-07-01

{gamma}-ray tracking in future HPGe arrays like AGATA will rely on pulse shape analysis (PSA) of multiple {gamma}-interactions. For this purpose, a simple and fast procedure was developed which enabled the first full characterization of a segmented large volume HPGe detector. An analytical model for the hole mobility in a Ge crystal lattice was developed to describe the hole drift anisotropy with experimental velocity values along the crystal axis as parameters. The new model is based on the drifted Maxwellian hole distribution in Ge. It is verified by reproducing successfully experimental longitudinal hole anisotropy data. A comparison between electron and hole mobility shows large differences for the longitudinal and tangential velocity anisotropy as a function of the electrical field orientation. Measurements on a 12 fold segmented, n-type, large volume, irregular shaped HPGe detector were performed in order to determine the parameters of anisotropic mobility for electrons and holes as charge carriers created by {gamma}-ray interactions. To characterize the electron mobility the complete outer detector surface was scanned in small steps employing photopeak interactions at 60 keV. A precise measurement of the hole drift anisotropy was performed with 356 keV rays. The drift velocity anisotropy and crystal geometry cause considerable rise time differences in pulse shapes depending on the position of the spatial charge carrier creation. Pulse shapes of direct and transient signals are reproduced by weighting potential calculations with high precision. The measured angular dependence of rise times is caused by the anisotropic mobility, crystal geometry, changing field strength and space charge effects. Preamplified signals were processed employing digital spectroscopy electronics. Response functions, crosstalk contributions and averaging procedures were taken into account implying novel methods due to the segmentation of the Ge-crystal and the digital electronics

High efficiency scintillation detectors

International Nuclear Information System (INIS)

Noakes, J.E.

1976-01-01

A scintillation counter consisting of a scintillation detector, usually a crystal scintillator optically coupled to a photomultiplier tube which converts photons to electrical pulses is described. The photomultiplier pulses are measured to provide information on impinging radiation. In inorganic crystal scintillation detectors to achieve maximum density, optical transparency and uniform activation, it has been necessary heretofore to prepare the scintillator as a single crystal. Crystal pieces fail to give a single composite response. Means are provided herein for obtaining such a response with crystal pieces, such means comprising the combination of crystal pieces and liquid or solid organic scintillator matrices having a cyclic molecular structure favorable to fluorescence. 8 claims, 6 drawing figures

Advantages and Limits of 4H-SIC Detectors for High- and Low-Flux Radiations

Science.gov (United States)

Sciuto, A.; Torrisi, L.; Cannavò, A.; Mazzillo, M.; Calcagno, L.

2017-11-01

Silicon carbide (SiC) detectors based on Schottky diodes were used to monitor low and high fluxes of photons and ions. An appropriate choice of the epilayer thickness and geometry of the surface Schottky contact allows the tailoring and optimizing the detector efficiency. SiC detectors with a continuous front electrode were employed to monitor alpha particles in a low-flux regime emitted by a radioactive source with high energy (>5.0 MeV) or generated in an ion implanter with sub-MeV energy. An energy resolution value of 0.5% was measured in the high energy range, while, at energy below 1.0 MeV, the resolution becomes 10%; these values are close to those measured with a traditional silicon detector. The same SiC devices were used in a high-flux regime to monitor high-energy ions, x-rays and electrons of the plasma generated by a high-intensity (1016 W/cm2) pulsed laser. Furthermore, SiC devices with an interdigit Schottky front electrode were proposed and studied to overcome the limits of the such SiC detectors in the detection of low-energy (˜1.0 keV) ions and photons of the plasmas generated by a low-intensity (1010 W/cm2) pulsed laser. SiC detectors are expected to be a powerful tool for the monitoring of radioactive sources and ion beams produced by accelerators, for a complete characterization of radiations emitted from laser-generated plasmas at high and low temperatures, and for dosimetry in a radioprotection field.

Moiré volume Bragg grating filter with tunable bandwidth.

Science.gov (United States)

Mokhov, Sergiy; Ott, Daniel; Divliansky, Ivan; Zeldovich, Boris; Glebov, Leonid

2014-08-25

We propose a monolithic large-aperture narrowband optical filter based on a moiré volume Bragg grating formed by two sequentially recorded gratings with slightly different resonant wavelengths. Such recording creates a spatial modulation of refractive index with a slowly varying sinusoidal envelope. By cutting a specimen at a small angle, to a thickness of one-period of this envelope, the longitudinal envelope profile will shift from a sine profile to a cosine profile across the face of the device. The transmission peak of the filter has a tunable bandwidth while remaining at a fixed resonant wavelength by a transversal shift of incidence position. Analytical expressions for the tunable bandwidth of such a filter are calculated and experimental data from a filter operating at 1064 nm with bandwidth range 30-90 pm is demonstrated.

High rate behavior and discharge limits in micro-pattern detectors

CERN Document Server

Bressan, A; Pagano, P; Ropelewski, Leszek; Sauli, Fabio; Biagi, S F; Buzulutskov, A F; Gruwé, M; De Lentdecker, G; Mörmann, D; Sharma, A

1999-01-01

We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strip micromegas, micro-dot, gas electron multiplier, CAT (compteur à trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8. In multiple structures, where the gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our c...

Bandwidth-Efficient Communication through 225 MHz Ka-band Relay Satellite Channel

Science.gov (United States)

Downey, Joseph; Downey, James; Reinhart, Richard C.; Evans, Michael Alan; Mortensen, Dale John

2016-01-01

The communications and navigation space infrastructure of the National Aeronautics and Space Administration (NASA) consists of a constellation of relay satellites (called Tracking and Data Relay Satellites (TDRS)) and a global set of ground stations to receive and deliver data to researchers around the world from mission spacecraft throughout the solar system. Planning is underway to enhance and transform the infrastructure over the coming decade. Key to the upgrade will be the simultaneous and efficient use of relay transponders to minimize cost and operations while supporting science and exploration spacecraft. Efficient use of transponders necessitates bandwidth efficient communications to best use and maximize data throughput within the allocated spectrum. Experiments conducted with NASA's Space Communication and Navigation (SCaN) Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques, such as bandwidth-efficient modulations, in an operational flight system. Demonstrations of these new techniques in realistic flight conditions provides critical experience and reduces the risk of using these techniques in future missions. Efficient use of spectrum is enabled by using high-order modulations coupled with efficient forward error correction codes. This paper presents a high-rate, bandwidth-efficient waveform operating over the 225 MHz Ka-band service of the TDRS System (TDRSS). The testing explores the application of Gaussian Minimum Shift Keying (GMSK), 248-phase shift keying (PSK) and 1632- amplitude PSK (APSK) providing over three bits-per-second-per-Hertz (3 bsHz) modulation combined with various LDPC encoding rates to maximize throughput. With a symbol rate of 200 Mbaud, coded data rates of 1000 Mbps were tested in the laboratory and up to 800 Mbps over the TDRS 225 MHz channel. This paper will present on the high-rate waveform design, channel characteristics, performance results, compensation

Influence of Reduced Graphene Oxide on Effective Absorption Bandwidth Shift of Hybrid Absorbers.

Directory of Open Access Journals (Sweden)

Shahid Ameer

Full Text Available The magnetic nanoparticle composite NiFe2O4 has traditionally been studied for high-frequency microwave absorption with marginal performance towards low-frequency radar bands (particularly L and S bands. Here, NiFe2O4 nanoparticles and nanohybrids using large-diameter graphene oxide (GO sheets are prepared via solvothermal synthesis for low-frequency wide bandwidth shielding (L and S radar bands. The synthesized materials were characterized using XRD, SEM, FTIR and microwave magneto dielectric spectroscopy. The dimension of these solvothermally synthesized pristine particles and hybrids lies within 30-58 nm. Microwave magneto-dielectric spectroscopy was performed in the low-frequency region in the 1 MHz-3 GHz spectrum. The as-synthesized pristine nanoparticles and hybrids were found to be highly absorbing for microwaves throughout the L and S radar bands ( 4 GHz with limited selective bandwidth.

Metamaterial composite bandpass filter with an ultra-broadband rejection bandwidth of up to 240 terahertz

DEFF Research Database (Denmark)

Strikwerda, Andrew; Zalkovskij, Maksim; Lorenzen, Dennis Lund

2014-01-01

We present a metamaterial, consisting of a cross structure and a metal mesh filter, that forms a composite with greater functional bandwidth than any terahertz (THz) metamaterial to date. Metamaterials traditionally have a narrow usable bandwidth that is much smaller than common THz sources......, such as photoconductive antennas and difference frequency generation. The composite structure shown here expands the usable bandwidth to exceed that of current THz sources. To highlight the applicability of this combination, we demonstrate a series of bandpass filters with only a single pass band, with a central...... frequency (f) that is scalable from 0.86–8.51 THz, that highly extinguishes other frequencies up to >240 THz. The performance of these filters is demonstrated in experiment, using both air biased coherent detection and a Fourier transform infrared spectrometer (FTIR), as well as in simulation. We present...

Image simulation of high-speed imaging by high-pressure gas ionization detector

International Nuclear Information System (INIS)

Miao Jichen; Liu Ximing; Wu Zhifang

2005-01-01

The signal of the neighbor pixels is cumulated in Freight Train Inspection System because data fetch time is shorter than ion excursion time. This paper analyzes the pertinency of neighbor pixels and designs computer simulation method to generate some emulate images such as indicator image. The result indicates the high-pressure gas ionization detector can be used in high-speed digital radiography field. (authors)

Characteristics of an intrinsic germanium detector for measurement of soft x-rays from high-temperature plasmas

International Nuclear Information System (INIS)

Kumagai, Katsuaki; Matoba, Tohru; Funahashi, Akimasa; Kawakami, Tomohide

1976-09-01

An intrinsic germanium (Ge(I)) detector has been prepared for measurement of soft X-ray spectra from high-temperature tokamak plasmas. Its characteristics of photo-peak efficiency, escape-peak and Compton scattering were calibrated with standard radioisotopes and soft X-rays from the JFT-2a plasma, and compared with those of a lithium-drifted silicon (Si(Li)) detector. Features of the Ge(I) detector are as follows: (i) high detection efficiency in the high energy range, (ii) wide energy range for measurement of soft X-ray spectra, and (iii) low Compton scattering effect in measurement of continuous spectra. Its dead-layer depth is about 0.06μm, and the minimum detectable energies in the Ge(I) detector are similar to those in the Si(Li) detector. The Ge(I) detector is effective for measuring soft X-ray spectra from high-temperature tokamak plasmas. (auth.)

Terahertz bandwidth photonic Hilbert transformers based on synthesized planar Bragg grating fabrication.

Science.gov (United States)

Sima, Chaotan; Gates, J C; Holmes, C; Mennea, P L; Zervas, M N; Smith, P G R

2013-09-01

Terahertz bandwidth photonic Hilbert transformers are proposed and experimentally demonstrated. The integrated device is fabricated via a direct UV grating writing technique in a silica-on-silicon platform. The photonic Hilbert transformer operates at bandwidths of up to 2 THz (~16 nm) in the telecom band, a 10-fold greater bandwidth than any previously reported experimental approaches. Achieving this performance requires detailed knowledge of the system transfer function of the direct UV grating writing technique; this allows improved linearity and yields terahertz bandwidth Bragg gratings with improved spectral quality. By incorporating a flat-top reflector and Hilbert grating with a waveguide coupler, an ultrawideband all-optical single-sideband filter is demonstrated.

Nonlinear detection for a high rate extended binary phase shift keying system.

Science.gov (United States)

Chen, Xian-Qing; Wu, Le-Nan

2013-03-28

The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM) on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD) detector. The two detectors detect the received signals together with the special impacting filter (SIF) that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs), which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK) signal detection and can provide accurate posterior probability for LDPC decoding.

Nonlinear Detection for a High Rate Extended Binary Phase Shift Keying System

Directory of Open Access Journals (Sweden)

Le-Nan Wu

2013-03-01

Full Text Available The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD detector. The two detectors detect the received signals together with the special impacting filter (SIF that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs, which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK signal detection and can provide accurate posterior probability for LDPC decoding.

A new metasurface reflective structure for simultaneous enhancement of antenna bandwidth and gain

International Nuclear Information System (INIS)

Habib Ullah, M; Islam, M T

2014-01-01

A new bi-layered metasurface reflective structure (MRS) on a high-permittivity, low-loss, ceramic-filled, bio-plastic, sandwich-structured, dielectric substrate is proposed for the simultaneous enhancement of the bandwidth and gain of a dual band patch antenna. By incorporating the MRS with a 4 mm air gap between the MRS and the antenna, the bandwidth and gain of the dual band patch antenna are significantly enhanced. The reflection coefficient (S11 < −10 dB) bandwidth of the proposed MRS-loaded antenna increased by 240% (178%), and the average peak gain improved by 595% (128%) compared to the antenna alone in the lower (upper) band. Incremental improvements of the magnitude and directional patterns have been observed from the measured radiation patterns at the three resonant frequencies of 0.9 GHz, 3.7 GHz and 4.5 GHz. The effects of different configurations of the radiating patch and the ground plane on the reflection coefficient have been analyzed. In addition, the voltage standing wave ratio and input impedance have also been validated using a Smith chart. (paper)

A new metasurface reflective structure for simultaneous enhancement of antenna bandwidth and gain

Science.gov (United States)

Ullah, M. Habib; Islam, M. T.

2014-08-01

A new bi-layered metasurface reflective structure (MRS) on a high-permittivity, low-loss, ceramic-filled, bio-plastic, sandwich-structured, dielectric substrate is proposed for the simultaneous enhancement of the bandwidth and gain of a dual band patch antenna. By incorporating the MRS with a 4 mm air gap between the MRS and the antenna, the bandwidth and gain of the dual band patch antenna are significantly enhanced. The reflection coefficient (S11 < -10 dB) bandwidth of the proposed MRS-loaded antenna increased by 240% (178%), and the average peak gain improved by 595% (128%) compared to the antenna alone in the lower (upper) band. Incremental improvements of the magnitude and directional patterns have been observed from the measured radiation patterns at the three resonant frequencies of 0.9 GHz, 3.7 GHz and 4.5 GHz. The effects of different configurations of the radiating patch and the ground plane on the reflection coefficient have been analyzed. In addition, the voltage standing wave ratio and input impedance have also been validated using a Smith chart.

Dynamic Bandwidth Allocation with Effective Utilization of Polling Interval over WDM/TDM PON

Science.gov (United States)

Ni, Cuiping; Gan, Chaoqin; Gao, Ziyue

2014-12-01

WDM/TDM (wavelength-division multiplexing/time-division multiplexing) PON (passive optical network) appears to be an attractive solution for the next generation optical access networks. Dynamic bandwidth allocation (DBA) plays a crucial role in efficiently and fairly allocating the bandwidth among all users in WDM/TDM PON. In this paper, two dynamic bandwidth allocation schemes (DBA1 and DBA2) are proposed to eliminate the idle time of polling cycles (i.e. polling interval), improve bandwidth utilization and make full use of bandwidth resources. The two DBA schemes adjust the time slot of sending request information and make fair scheduling among users to achieve the effective utilization of polling interval in WDM/TDM PON. The simulation and theoretical analyses verify that the proposed schemes outperform the conventional DBA scheme. We also make comparisons between the two schemes in terms of bandwidth utilization and average packet delay to further demonstrate the effectiveness of the scheme of DBA2.

A highly-segmented neutron detector for the A1 experiment at MAMI

Energy Technology Data Exchange (ETDEWEB)

Schoth, Matthias [Institut fuer Kernphysik, Mainz (Germany); Collaboration: A1-Collaboration

2015-07-01

Electric and magnetic form factors of the neutron, are one of the defining properties to characterize its structure quantitatively. A planned physics program to improve the data base significantly requires high performance detection of relativistic neutrons. Exploiting the full potential of the high luminosity supplied by the MAMI accelerator, a novel neutron detector is being developed in the scope of the A1 collaboration. A large active detector volume of 0.96 m{sup 3} is required to achieve a high raw detection efficiency. The detector is subdivided into 2048 plastic scintillators to be able to cope with high background rates. The light is extracted via wavelength shifting fibres and then guided to multi anode photomultiplier. The signal is read out with FPGA based TDCs (TRBv3 developed at GSI). The energy of the signal is obtained via time over threshold information in combination with a suitable shaping and discriminating circuit. Prototype tests have been performed to optimize the choice of materials and geometry. The capability to detect neutrons in the relevant momentum range has been demonstrated using pion production. A Geant4 simulation using tracking algorithms evaluating the deposited energy is able to optimize key detector properties like particle id efficiency, multiplicity or the effective analyzing power for double polarized scattering experiments.

Preparation of High Purity CdTe for Nuclear Detector: Electrical and Nuclear Characterization

Science.gov (United States)

Zaiour, A.; Ayoub, M.; Hamié, A.; Fawaz, A.; Hage-ali, M.

High purity crystal with controllable electrical properties, however, control of the electrical properties of CdTe has not yet been fully achieved. Using the refined Cd and Te as starting materials, extremely high-purity CdTe single crystals were prepared by the traditional vertical THM. The nature of the defects involved in the transitions was studied by analyzing the position of the energy levels by TSC method. The resolution of 4.2 keV (FWHM) confirms the high quality and stability of the detectors: TSC spectrum was in coherence with detectors spectrum with a horizontal plate between 0.2 and 0.6 eV. The enhancement in resolution of detectors with a full width at half- maximum (less than 0.31 meV), lead to confirm that the combination of vacuum distillation and zone refining was very effective to obtain more purified CdTe single crystals for photovoltaic or nuclear detectors with better physical properties.

Research on multi-spectrum detector in high-energy dual-energy X-ray imaging system

International Nuclear Information System (INIS)

Li Qinghua; Wang Xuewu; Li Jianmin; Kang Kejun; Li Yuanjing; Zhong Huaqiang

2008-01-01

The high-energy dual-energy X-ray imaging system can discriminate the material of the objects inspected, but when the objects are too thin, the discrimination becomes very difficult. This paper proposes the use of multi-spectrum detector to improve the ability to discriminate thin material, and a series of simulation were done with the Monte Carlo method. Firstly the X-ray depositions in the detectors with different thickness were calculated, and then the discrimination effects with different detector structure and parameters were calculated. The simulation results validated that using appropriate multi-spectrum detector can improve the discrimination accuracy of thin material, particularly thin high-Z material. (authors)

High-pressure plastic scintillation detector for measuring radiogenic gases in flow systems

Science.gov (United States)

Schell, W. R.; Vives-Batlle, J.; Yoon, S. R.; Tobin, M. J.

1999-02-01

Radioactive gases are emitted into the atmosphere from nuclear electric power and nuclear fuel reprocessing plants, from hospitals discarding xenon used in diagnostic medicine, as well as from nuclear weapons tests. A high-pressure plastic scintillation detector was constructed to measure atmospheric levels of such radioactive gases by detecting the beta and internal conversion (IC) electron decays. Operational tests and calibrations were made that permit integration of the flow detectors into a portable Gas Analysis, Separation and Purification system (GASP). The equipment developed can be used for measuring fission gases released from nuclear reactor sources and/or as part of monitoring equipment for enforcing the Comprehensive Test Ban Treaty. The detector is being used routinely for in-line gas separation efficiency measurements, at the elevated operational pressures used for the high-pressure swing analysis system (2070 kPa) and at flow rates of 5-15 l/min [1, 2]. This paper presents the design features, operational methods, calibration, and detector applications.

High-pressure plastic scintillation detector for measuring radiogenic gases in flow systems

International Nuclear Information System (INIS)

Schell, W.R.; Vives-Batlle, J.; Yoon, S.R; Tobin, M.J.

1999-01-01

Radioactive gases are emitted into the atmosphere from nuclear electric power and nuclear fuel reprocessing plants, from hospitals discarding xenon used in diagnostic medicine, as well as from nuclear weapons tests. A high-pressure plastic scintillation detector was constructed to measure atmospheric levels of such radioactive gases by detecting the beta and internal conversion (IC) electron decays. Operational tests and calibrations were made that permit integration of the flow detectors into a portable Gas Analysis, Separation and Purification system (GASP). The equipment developed can be used for measuring fission gases released from nuclear reactor sources and/or as part of monitoring equipment for enforcing the Comprehensive Test Ban Treaty. The detector is being used routinely for in-line gas separation efficiency measurements, at the elevated operational pressures used for the high-pressure swing analysis system (2070 kPa) and at flow rates of 5-15 l/min . This paper presents the design features, operational methods, calibration, and detector applications

Multi-channel imaging cytometry with a single detector

Science.gov (United States)

Locknar, Sarah; Barton, John; Entwistle, Mark; Carver, Gary; Johnson, Robert

2018-02-01

Multi-channel microscopy and multi-channel flow cytometry generate high bit data streams. Multiple channels (both spectral and spatial) are important in diagnosing diseased tissue and identifying individual cells. Omega Optical has developed techniques for mapping multiple channels into the time domain for detection by a single high gain, high bandwidth detector. This approach is based on pulsed laser excitation and a serial array of optical fibers coated with spectral reflectors such that up to 15 wavelength bins are sequentially detected by a single-element detector within 2.5 μs. Our multichannel microscopy system uses firmware running on dedicated DSP and FPGA chips to synchronize the laser, scanning mirrors, and sampling clock. The signals are digitized by an NI board into 14 bits at 60MHz - allowing for 232 by 174 pixel fields in up to 15 channels with 10x over sampling. Our multi-channel imaging cytometry design adds channels for forward scattering and back scattering to the fluorescence spectral channels. All channels are detected within the 2.5 μs - which is compatible with fast cytometry. Going forward, we plan to digitize at 16 bits with an A-toD chip attached to a custom board. Processing these digital signals in custom firmware would allow an on-board graphics processing unit to display imaging flow cytometry data over configurable scanning line lengths. The scatter channels can be used to trigger data buffering when a cell is present in the beam. This approach enables a low cost mechanically robust imaging cytometer.

Particle identification using digital pulse shape discrimination in a nTD silicon detector with a 1 GHz sampling digitizer

Science.gov (United States)

Mahata, K.; Shrivastava, A.; Gore, J. A.; Pandit, S. K.; Parkar, V. V.; Ramachandran, K.; Kumar, A.; Gupta, S.; Patale, P.

2018-06-01

In beam test experiments have been carried out for particle identification using digital pulse shape analysis in a 500 μm thick Neutron Transmutation Doped (nTD) silicon detector with an indigenously developed FPGA based 12 bit resolution, 1 GHz sampling digitizer. The nTD Si detector was used in a low-field injection setup to detect light heavy-ions produced in reactions of ∼ 5 MeV/A 7Li and 12C beams on different targets. Pulse height, rise time and current maximum have been obtained from the digitized charge output of a high bandwidth charge and current sensitive pre-amplifier. Good isotopic separation have been achieved using only the digitized charge output in case of light heavy-ions. The setup can be used for charged particle spectroscopy in nuclear reactions involving light heavy-ions around the Coulomb barrier energies.

Analysis of blocking probability for OFDM-based variable bandwidth optical network

Science.gov (United States)

Gong, Lei; Zhang, Jie; Zhao, Yongli; Lin, Xuefeng; Wu, Yuyao; Gu, Wanyi

2011-12-01

Orthogonal Frequency Division Multiplexing (OFDM) has recently been proposed as a modulation technique. For optical networks, because of its good spectral efficiency, flexibility, and tolerance to impairments, optical OFDM is much more flexible compared to traditional WDM systems, enabling elastic bandwidth transmissions, and optical networking is the future trend of development. In OFDM-based optical network the research of blocking rate has very important significance for network assessment. Current research for WDM network is basically based on a fixed bandwidth, in order to accommodate the future business and the fast-changing development of optical network, our study is based on variable bandwidth OFDM-based optical networks. We apply the mathematical analysis and theoretical derivation, based on the existing theory and algorithms, research blocking probability of the variable bandwidth of optical network, and then we will build a model for blocking probability.

Detector dead-time effects and paralyzability in high-speed quantum key distribution

International Nuclear Information System (INIS)

Rogers, Daniel J; Bienfang, Joshua C; Nakassis, Anastase; Xu Hai; Clark, Charles W

2007-01-01

Recent advances in quantum key distribution (QKD) have given rise to systems that operate at transmission periods significantly shorter than the dead times of their component single-photon detectors. As systems continue to increase in transmission rate, security concerns associated with detector dead times can limit the production rate of sifted bits. We present a model of high-speed QKD in this limit that identifies an optimum transmission rate for a system with given link loss and detector response characteristics