Wireless SAW passive tag temperature measurement in the collision case

Science.gov (United States)

Sorokin, A.; Shepeta, A.; Wattimena, M.

2018-04-01

This paper describes temperature measurement in the multisensor systems based on the radio-frequency identification SAW passive tags which are currently applied in the electric power systems and the switchgears. Different approaches of temperature measurement in the collision case are shown here. The study is based on the tag model with specific topology, which allows us to determine temperature through the response signal with time-frequency information. This research considers the collision case for several passive tags as the temperature sensors which are placed in the switchgear. This research proposal is to analyze the possibility of using several SAW passive sensors in the collision case. We consider the using of the different typical elements for passive surface acoustic wave tag which applies as an anticollision passive sensor. These wireless sensors based on the surface acoustic waves tags contain specifically coded structures. This topology makes possible the reliability of increasing tag identification and the temperature measurement in the collision case. As the results for this case we illustrate simultaneous measurement of at least six sensors.

Measurement of fast assembly spectra using time-of-flight method

International Nuclear Information System (INIS)

Duquesne, Henry; Rotival, Michel; Schmitt, Andre; Allard, Christian; De Keyser, Albert; Hortsmann, Henri

1975-07-01

Measurement of neutron spectra made in fast subcritical assemblies HUG 3 and PHUG 3 (uranium-graphite and plutonium-graphite) utilizing time-of-flight techniques are described. The matrix were excited by the pulsed neutron source from the BCMN Linac beam impinging on a target of natural uranium. Details of the experimental procedure, safety studies, detector calibration and data reduction are given [fr

Measuring and Predicting Tag Importance for Image Retrieval.

Science.gov (United States)

Li, Shangwen; Purushotham, Sanjay; Chen, Chen; Ren, Yuzhuo; Kuo, C-C Jay

2017-12-01

Textual data such as tags, sentence descriptions are combined with visual cues to reduce the semantic gap for image retrieval applications in today's Multimodal Image Retrieval (MIR) systems. However, all tags are treated as equally important in these systems, which may result in misalignment between visual and textual modalities during MIR training. This will further lead to degenerated retrieval performance at query time. To address this issue, we investigate the problem of tag importance prediction, where the goal is to automatically predict the tag importance and use it in image retrieval. To achieve this, we first propose a method to measure the relative importance of object and scene tags from image sentence descriptions. Using this as the ground truth, we present a tag importance prediction model to jointly exploit visual, semantic and context cues. The Structural Support Vector Machine (SSVM) formulation is adopted to ensure efficient training of the prediction model. Then, the Canonical Correlation Analysis (CCA) is employed to learn the relation between the image visual feature and tag importance to obtain robust retrieval performance. Experimental results on three real-world datasets show a significant performance improvement of the proposed MIR with Tag Importance Prediction (MIR/TIP) system over other MIR systems.

Use of a large time-compensated scintillation detector in neutron time-of-flight measurements

International Nuclear Information System (INIS)

Goodman, C.D.

1979-01-01

A scintillator for neutron time-of-flight measurements is positioned at a desired angle with respect to the neutron beam, and as a function of the energy thereof, such that the sum of the transit times of the neutrons and photons in the scintillator are substantially independent of the points of scintillations within the scintillator. Extrapolated zero timing is employed rather than the usual constant fraction timing. As a result, a substantially larger scintillator can be employed that substantially increases the data rate and shortens the experiment time. 3 claims

The dynamic method for time-of-flight measurement of thermal neutron spectra from pulsed sources

International Nuclear Information System (INIS)

Pepyolyshev, Yu.N.; Chuklyaev, S.V.; Tulaev, A.B.; Bobrakov, V.F.

1995-01-01

A time-of-flight method for measurement of thermal neutron spectra in pulsed neutron sources with an efficiency more than 10 5 times higher than the standard method is described. The main problems associated with the electric current technique for time-of-flight spectra measurement are examined. The methodical errors, problems of special neutron detector design and other questions are discussed. Some experimental results for spectra from the surfaces of water and solid methane moderators obtained at the IBR-2 pulsed reactor (Dubna, Russia) are presented. (orig.)

Clock-transport synchronisation for neutrino time-of-flight measurements

International Nuclear Information System (INIS)

Field, J.H.

2012-01-01

A method to synchronise, at the sub-nanosecond level, clocks used for neutrino time-of-flight measurements is proposed. Clocks situated near the neutrino source and target are compared with a moveable clock that is transported between them. The general-relativistic theory of the procedure was tested and verified in an experiment performed by Hafele and Keating in 1972. It is suggested that use of such a synchronisation method may contribute to a precise test of the Sagnac effect - a measured velocity greater than c - for neutrinos of the proposed LBNE beam between Fermilab and the Homestake mine. (orig.)

Correlation function measurement of uranium casting driven by tagged DT neutrons

International Nuclear Information System (INIS)

Li Jiansheng; Ye Cenming; Xie Wenxiong; Huang Po; Zeng Liheng; Jin Yu; Xie Qilin; Zhang Yi

2013-01-01

Background: In the nuclear disarmament process, the measurement and verification of uranium casting in sealed container are important to process control and treaty implementation. It is a difficult and hot problem to verify uranium casting in a sealed metal container, due to the weak intensity of neutron and gamma rays of uranium. Purpose: We want to measure the correlation functions of different casting in uranium casting verifications. Methods: Two BC501 scintillation detectors are placed outside the tagged neutron cone and in opposite position. The α detector forms the first channel pulse signal, while the two BC501 scintillation detectors form the second and third channel pulse signals. Those three pulsed time series are recorded by high speed acquisition system. The correlation functions between these signals are calculated by the time series. Results: Putting the two BC501 detectors into the tagged neutron cone, the time of flight for the 14 MeV neutron is measured. The FWHM in TOF spectrum is 2.0 ns. Putting the two BC501 detectors outside the tagged neutron cone, the correlation functions measured by high speed acquisition system and MCA are consistent. The spontaneous neutron decay constants of the castings are measured by γ rays. The decay constant of 6.5 kg Pb component is 184 μs -1 . The decay constants of 4 kg and 15 kg HEU casting are 210 μs -1 and 128 μs -1 , respectively. The correlation functions C 12 (τ), C 13 (τ) and C 23 (τ) are acquired. In C 12 (C), the γ ray peak coming from the inelastic reaction of 14-MeV neutrons with the casting is 5.0 ns before the neutron peak of fission chain. This time difference can estimate the casting position in container. The integrations of the C 12 (τ), C 13 (τ) and C 23 (τ) increase with the casting mass. The C 23 (τ) values of Pb component and DU casting are far less than the values of HEU casting. The C 23 (τ) integration of Pb component is 3.0% comparing with 15-kg HEU casting, while the

A measurement of Rb using mutually exclusive tags

Science.gov (United States)

Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Miquel, R.; Mir, Ll. M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bazarko, A. O.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Turnbull, R. M.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Ghete, V. M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Berlich, R.; Blum, W.; Brown, D.; Büscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nilolic, I.; Schune, M.-H.; Simion, S.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Kelly, M. S.; Lehto, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Charles, E.; Elmer, P.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Greening, T. C.; Hayes, O. J.; Hu, H.; Jin, S.; McNamara, P. A.; Nachtman, J. M.; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Sau, Lan Wu; Wu, X.; Yamartino, J. M.; Zobernig, G.

1997-02-01

A measurement of Rb using five mutually exclusive hemisphere tags has been performed by ALEPH using the full LEP1 statistics. Three tags are designed to select the decay of the Z0 to b quarks, while the remaining two selectZ0 decays to c and light quarks, and are used to measure the tagging efficiencies. The result, Rb = 0.2159 +/- 0.0009 (stat) +/- 0.0011 (syst), is in agreement with the electroweak theory prediction of 0.2158 +/- 0.0003.

Process-independent radiative-correction formula for single-tag and double-tag measurements of γγ reactions

International Nuclear Information System (INIS)

Ong, S.; Kessler, P.

1988-01-01

A simple and process-independent formula is given for radiative corrections in single-tag and double-tag measurements of γγ reactions. Its conditions of validity are that (i) in the γγ process itself all particles produced are detected and (ii) final-state particles, including the tagged electron(s), are measured with a good resolution in energy and momentum

The Dynamic Method for Time-of-Flight Measurement of Thermal Neutron Spectra from Pulsed Sources

International Nuclear Information System (INIS)

Pepelyshev, Yu.N.; Tulaev, A.B.; Bobrakov, V.F.

1994-01-01

The time-of-flight method for a measurement of thermal neutron spectra in the pulsed neutron sources with high efficiency of neutron registration, more than 10 5 times higher in comparison with traditional one, is described. The main problems connected with the electric current technique for time-of-flight spectra measurement are examined. The methodical errors, problems of a special neutron detector design and other questions are discussed. Some experimental results, spectra from surfaces of the water and solid methane moderators, obtained in the pulsed reactor IBR-2 (Dubna, Russia) are presented. 4 refs., 5 figs

Electric field measurement in the ionosphere using the time-of-flight technique

International Nuclear Information System (INIS)

Nakamura, Masato; Hayakawa, Hajime; Tsuruda, Koichiro

1989-01-01

The first successful electric field measurement in the ionosphere using the time-of-flight technique with a lithium ion beam was carried out on a S-520 sounding rocket launched from Kagoshima Space Center, Japan on January 15, 1987. The purpose of this experiment was to prove the validity of the time-of-flight technique when it is applied to the measurement of the dc electric field in the ionosphere. A time-coded ion beam was ejected from the rocket in the direction perpendicular to the Earth's magnetic field. The beam returned to the rocket twice per rocket spin when the initial beam direction was nearly perpendicular to the electric field. The electric field and the magnetic field were derived from the travel time of these return lithium ions. The accuracy of the electric field determination was ± 0.3 mV/m. The direction of the electric field was obtained from the direction of the returning ion beam after about one ion gyration. The main constituent of the measured electric field was a V x B field due to the rocket motion across the geomagnetic field. The ambient field was less than 1 mV/m. The magnetic field was measured with an accuracy of ± 2.7 nT in this experiment

Measurement of detector neutron energy response using time-of-flight techniques

International Nuclear Information System (INIS)

Janee, H.S.

1973-09-01

The feasibility of using time-of-flight techniques at the EG and G/AEC linear accelerator for measuring the neutron response of relatively sensitive detectors over the energy range 0.5 to 14 MeV has been demonstrated. The measurement technique is described in detail as are the results of neutron spectrum measurements from beryllium and uranium photoneutron targets. The sensitivity of a fluor photomultiplier LASL detector with a 2- by 1-inch NE-111 scintillator was determined with the two targets, and agreement in the region of overlap was very good. (U.S.)

Postprandial phase time influences the uptake of TAG from postprandial TAG-rich lipoproteins by THP-1 macrophages.

Science.gov (United States)

Cabello-Moruno, Rosana; Sinausia, Laura; Botham, Kathleen M; Montero, Emilio; Avella, Michael; Perona, Javier S

2014-11-14

Postprandial TAG-rich lipoproteins (TRL) can be taken up by macrophages, leading to the formation of foam cells, probably via receptor-mediated pathways. The present study was conducted to investigate whether the postprandial time point at which TRL are collected modulates this process. A meal containing refined olive oil was given to nine healthy young men and TRL were isolated from their serum at 2, 4 and 6 h postprandially. The lipid class and apoB compositions of TRL were determined by HPLC and SDS-PAGE, respectively. The accumulation of lipids in macrophages was determined after the incubation of THP-1 macrophages with TRL. The gene expression of candidate receptors was measured by real-time PCR. The highest concentrations of TAG, apoB48 and apoB100 in TRL were observed at 2 h after the consumption of the test meal. However, excessive intracellular TAG accumulation in THP-1 macrophages was observed in response to incubation with TRL isolated at 4 h, when their particle size (estimated as the TAG:apoB ratio) was intermediate. The abundance of mRNA transcripts in macrophages in response to incubation with TRL was down-regulated for LDL receptor (LDLR), slightly up-regulated for VLDL receptor and remained unaltered for LDLR-related protein, but no effect of the postprandial time point was observed. In contrast, the mRNA expression of scavenger receptors SRB1, SRA2 and CD36 was higher when cells were incubated with TRL isolated at 4 h after the consumption of the test meal. In conclusion, TRL led to excessive intracellular TAG accumulation in THP-1 macrophages, which was greater when cells were incubated with intermediate-sized postprandial TRL isolated at 4 h and was associated with a significant increase in the mRNA expression of scavenger receptors.

TORCH: A Large-Area Detector for Precision Time-of-Flight Measurements at LHCb

CERN Document Server

Harnew, N

2012-01-01

The TORCH (Time Of internally Reflected CHerenkov light) is an innovative high-precision time-of-flight detector which is suitable for large areas, up to tens of square metres, and is being developed for the upgraded LHCb experiment. The TORCH provides a time-of-flight measurement from the imaging of photons emitted in a 1 cm thick quartz radiator, based on the Cherenkov principle. The photons propagate by total internal reflection to the edge of the quartz plane and are then focused onto an array of Micro-Channel Plate (MCP) photon detectors at the periphery of the detector. The goal is to achieve a timing resolution of 15 ps per particle over a flight distance of 10 m. This will allow particle identification in the challenging momentum region up to 20 GeV/c. Commercial MCPs have been tested in the laboratory and demonstrate the required timing precision. An electronics readout system based on the NINO and HPTDC chipset is being developed to evaluate an 8×8 channel TORCH prototype. The simulated performance...

Time-of-flight techniques applied to neutron spectra measurements in fast subcritical assemblies

International Nuclear Information System (INIS)

Rotival, Michel

1975-04-01

Time-of-flight measurements on Uranium-Graphite assemblies were performed using the BCMN linear accelerator. Methods to provide scalar spectra averaged over a core cell from these experimental results are described [fr

ALICE Time Of Flight Detector

CERN Multimedia

Alici, A

2013-01-01

Charged particles in the intermediate momentum range are identified in ALICE by the Time Of Flight (TOF) detector. The time measurement with the TOF, in conjunction with the momentum and track length measured by the tracking detector, is used to calculate the particle mass.

Time-of-Flight Measurement of the Speed of Sound in a Metal Bar

Science.gov (United States)

Ganci, Salvatore

2016-01-01

A simple setup was designed for a "time-of-flight" measurement of the sound speed in a metal bar. The experiment requires low cost components and is very simple to understand by students. A good use of it is as a demonstration experiment.

Automatic identification of NDA measured items: Use of E-tags

International Nuclear Information System (INIS)

Chitumbo, K.; Olsen, R.; Hatcher, C.R.; Kadner, S.P.

1995-01-01

This paper describes how electronic identification devices or E-tags could reduce the time spent by LAEA inspectors making nondestructive assay (NDA) measurements. As one example, the use of E-tags with a high-level neutron coincidence counter (HLNC) is discussed in detail. Sections of the paper include inspection procedures, system description, software, and future plans. Mounting of E-tabs, modifications to the HLNC, and the use of tamper indicating devices are also discussed. The technology appears to have wide application to different types of nuclear facilities and inspections and could significantly change NDA inspection procedures

On the optimal identification of tag sets in time-constrained RFID configurations.

Science.gov (United States)

Vales-Alonso, Javier; Bueno-Delgado, María Victoria; Egea-López, Esteban; Alcaraz, Juan José; Pérez-Mañogil, Juan Manuel

2011-01-01

In Radio Frequency Identification facilities the identification delay of a set of tags is mainly caused by the random access nature of the reading protocol, yielding a random identification time of the set of tags. In this paper, the cumulative distribution function of the identification time is evaluated using a discrete time Markov chain for single-set time-constrained passive RFID systems, namely those ones where a single group of tags is assumed to be in the reading area and only for a bounded time (sojourn time) before leaving. In these scenarios some tags in a set may leave the reader coverage area unidentified. The probability of this event is obtained from the cumulative distribution function of the identification time as a function of the sojourn time. This result provides a suitable criterion to minimize the probability of losing tags. Besides, an identification strategy based on splitting the set of tags in smaller subsets is also considered. Results demonstrate that there are optimal splitting configurations that reduce the overall identification time while keeping the same probability of losing tags.

Exploiting phase measurements of EPC Gen2 RFID tags

NARCIS (Netherlands)

Huiting, J.; Flisijn, Hubert; Kokkeler, Andre B.J.; Smit, Gerardus Johannes Maria

2013-01-01

This paper presents a 2d localization system for UHF RFID tags. By measuring the phase between the transmitted continuous wave and received backscatter from the tag at different frequencies, it is possible to estimate the distance between the reader and tag. By determining distance estimates to

Measurement of decay time of K→π0π0 and tagging the KL and KS in the NA48 experiment at CERN

International Nuclear Information System (INIS)

Crepe, Sabine

1998-05-01

The NA48 experiment aims to measure, in the neutral kaon system and with a precision of 0.0002, the real part of the ratio between the amplitudes of the direct and indirect breaking of the CP symmetry. To reach the requested precision NA48 has to minimize systematic uncertainties and thus has chosen to detect simultaneously and in the same fiducial region the long and short-lived (K L and K S ) decays into two charged or neutral pions. Consequently, kaon tagging is necessary. It is done using the time coincidences between these decays and the protons at the origin of the K S beam. As mis-tagging leads to large bias for the NA48 measurement, it has to be carefully evaluated and understood. It could be due either to detectors inefficiencies or to random coincidences between K L and protons. The detector used for the tagging of the neutral modes is the liquid krypton calorimeter. Its time performances, studied with 1996 and 1997 data, appear to be very good: for two neutral pion decays its resolution is 250 ps and its inefficiency smaller than 0.0001. Moreover, the amount of random coincidences between protons and K L is directly related to the instantaneous rate of the proton beam. The time structures of this beam have been studied, Several frequencies have been found and the effective spill length has been measured to be only 75 per cent of the total one. Finally, the uncertainties on the real part of the ratio between direct and indirect CP breaking due to mis-tagging have been evaluated for the 1997 data. They are smaller than the statistical one. (author)

Time-of-flight measurement in the DZero Central Fiber Tracker

International Nuclear Information System (INIS)

Juan Estrada

2003-01-01

We continue evaluation of the new electronics developed for the Central Fiber Tracker and Preshower detectors. With the custom TriP chip and MCM II we have measured the position of the hits along the fiber by comparing the time of arrival of the photons at the VLPC with the expected timing relative to the beam. The measured rms resolution at the center of the fibers is 46cm for hits with more than 8 photo-electrons and is dominated by the statistics of photon arrival time. The corresponding resolution near the ends of the fibers (where more photoelectrons are collected) is calculated to be of order 27cm. With a second submission of the TriP chip to add the time-of-flight measuring capability we will effectively double the number of channels in the central fiber tracker. This capability will increase the maximum luminosity at which D0 can do tracking from ∼ 100 · 10 30 cm -2 s -1 to ∼ 200 · 10 30 cm -2 s -1 (at a bench mark tracking specification). The cost of replacing the electronics is of order $500K and the necessary lead time is 1.5 years

Monte-Carlo studies of the performance of scintillator detectors for time-of-flight measurements

International Nuclear Information System (INIS)

Yang, X.H.

1995-01-01

In this paper we report on a Monte-Carlo program, SToF, developed to evaluate the performance of scintillator-based Time-of-Flight (TOF) detectors. This program has been used in the design of the TOF system for the PHENIX experiment at RHIC. The program was used to evaluate the intrinsic time-of-flight resolution of various scintillator and light-guide geometries, and the results of these simulations are presented here. The simulation results agree extremely well with measured pulse-height and time distributions with one adjustable parameter. These results, thus, explain also the reduced quantities, such as the position dependence of the time resolution, etc, implying that SToF will be generally useful for estimating the performance of TOF detectors. ((orig.))

Design, construction, characterization, and use of a detector to measure time of flight of cosmic rays

Science.gov (United States)

Araujo, A. C.; Felix, J.

2017-01-01

In the study of cosmic rays, measurements of time of flight and momentum have been used to identify incident particles from its physical properties, like mass. In this document we present the design, construction, characterization, and operation of a detector to measure time of flight of cosmic rays. The device is comprised of three small plates of plastic scintillator arranged in vertical straight line, coupled to one photomultiplier tube. The analogical output has been connected to a data acquisition system to obtain the number of digital pulses per millisecond. We present details of design, construction, operation, and preliminary results.

Ion temperature measurement of indirectly-driven implosions using a geometry-compensated neutron time-of-flight detector

International Nuclear Information System (INIS)

Murphy, T.J.; Lerche, R.A.; Bennett, C.; Howe, G.

1994-05-01

A geometry-compensated neutron time-of-flight detector has been constructed and used on Nova to measure ion temperatures from indirectly-driven implosions with yields between 2.5 and 5 x 10 9 DD neutrons. The detector, which has an estimated response time of 250 ps, was located 150 cm from the targets. Due to the long decay time of the scintillator, the time-of-flight signal must be unfolded from the measured detector signal. Several methods for determining the width of the neutron energy spectrum from the data have been developed and give similar results. Scattered x rays continue to be a problem for low yield shots, but should be brought under control with adequate shielding

Ion-temperature measurement of indirectly driven implosions using a geometry-compensated neutron time-of-flight detector

International Nuclear Information System (INIS)

Murphy, T.J.; Lerche, R.A.; Bennett, C.; Howe, G.

1995-01-01

A geometry-compensated neutron time-of-flight detector has been constructed and used on Nova to measure ion temperatures from indirectly driven implosions with yields between 2.5 and 5x10 9 DD neutrons. The detector, which has an estimated respond time of 250 ps, was located 150 cm from the targets. Due to the long decay time of the scintillator, the time-of-flight signal must be unfolded from the measured detector signal. Several methods for determining the width of the neutron energy spectrum from the data have been developed and give similar results. Scattered x rays continue to be a problem for low yield shots, but should be brought under control with adequate shielding

A Measurement of $R_b$ using Mutually Exclusive Tags

CERN Document Server

Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Miquel, R; Mir, L M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Becker, U; Bazarko, A O; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Ghete, V M; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Coyle, P; Diaconu, C A; Etienne, F; Konstantinidis, N P; Leroy, O; Motsch, F; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Berlich, R; Blum, Walter; Brown, D; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Schune, M H; Simion, S; Tournefier, E; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; Gao, Y S; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zobernig, G

1997-01-01

A measurement of $R_b$ using five mutually exclusive hemisphere tags has been pe rformed by ALEPH using the full LEP1 statistics. Three tags are designed to sele ct the decay of the $Z^0$ to $b$ quarks, while the remaining two select $Z^0$ decays to $c$ and light quarks, and are used to measure the tagging efficiencies. The result, {$R_b~=~0.2159~\\pm~0.0009\\mbox{(stat)}~\\pm 0.0011\\mbox{(syst)}$}, is in agreement with the electroweak theory prediction of $0.2158 \\pm 0.0003$.

A measurement of Rb using a lifetime-mass tag

Science.gov (United States)

Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Miquel, R.; Mir, Ll. M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bazarko, A. O.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Turnbull, R. M.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Ghete, V. M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Berlich, R.; Blum, W.; Brown, D.; Büscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Schune, M.-H.; Simion, S.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Kelly, M. S.; Lehto, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Charles, E.; Elmer, P.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Greening, T. C.; Hayes, O. J.; Hu, H.; Jin, S.; McNamara, P. A.; Nachtman, J. M.; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zobernig, G.

1997-02-01

ALEPH's published measurement of Rb = Γ(Z -> bb)/Γ(Z -> hadrons) using a lifetime tag is updated using the full LEP 1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the b/c hadron mass difference. Furthermore, the algorithm used to reconstruct the event primary vertex is designed so as to reduce correlations between the two hemispheres of an event. The value of Rb is measured to be 0.2167 +/- 0.0011 (stat) +/- 0.0013 (syst).

A magnetic particle time-of-flight (MagPTOF) diagnostic for measurements of shock- and compression-bang time at the NIF (invited)

Energy Technology Data Exchange (ETDEWEB)

Rinderknecht, H. G., E-mail: hgr@mit.edu; Sio, H.; Frenje, J. A.; Gatu Johnson, M.; Zylstra, A. B.; Sinenian, N.; Rosenberg, M. J.; Li, C. K.; Sèguin, F. H.; Petrasso, R. D. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Magoon, J.; Agliata, A.; Shoup, M.; Glebov, V. U.; Hohenberger, M.; Stoeckl, C.; Sangster, T. C. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States); Ayers, S.; Bailey, C. G.; Rygg, J. R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

2014-11-15

A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D{sup 3}He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D{sup 3}He-proton signal-to-background by a factor of 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D{sup 3}He-filled surrogate implosions at the NIF.

A magnetic particle time-of-flight (MagPTOF) diagnostic for measurements of shock- and compression-bang time at the NIF (invited).

Science.gov (United States)

Rinderknecht, H G; Sio, H; Frenje, J A; Magoon, J; Agliata, A; Shoup, M; Ayers, S; Bailey, C G; Gatu Johnson, M; Zylstra, A B; Sinenian, N; Rosenberg, M J; Li, C K; Sèguin, F H; Petrasso, R D; Rygg, J R; Kimbrough, J R; Mackinnon, A; Bell, P; Bionta, R; Clancy, T; Zacharias, R; House, A; Döppner, T; Park, H S; LePape, S; Landen, O; Meezan, N; Robey, H; Glebov, V U; Hohenberger, M; Stoeckl, C; Sangster, T C; Li, C; Parat, J; Olson, R; Kline, J; Kilkenny, J

2014-11-01

A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D(3)He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D(3)He-proton signal-to-background by a factor of 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D(3)He-filled surrogate implosions at the NIF.

Measurement and simulation of the inelastic resolution function of a time-of-flight spectrometer

International Nuclear Information System (INIS)

Roth, S.V.; Zirkel, A.; Neuhaus, J.; Petry, W.; Bossy, J.; Peters, J.; Schober, H.

2002-01-01

The deconvolution of inelastic neutron scattering data requires the knowledge of the inelastic resolution function. The inelastic resolution function of the time-of-flight spectrometer IN5/ILL has been measured by exploiting the sharp resonances of the roton and maxon excitations in superfluid 4 He for the two respective (q,ω) values. The calculated inelastic resolution function for three different instrumental setups is compared to the experimentally determined resolution function. The agreement between simulation and experimental data is excellent, allowing us in principle to extrapolate the simulations and thus to determine the resolution function in the whole accessible dynamic range of IN5 or any other time-of-flight spectrometer. (orig.)

Measurement and simulation of the inelastic resolution function of a time-of-flight spectrometer

CERN Document Server

Roth, S V; Neuhaus, J; Petry, W; Bossy, J; Peters, J; Schober, H

2002-01-01

The deconvolution of inelastic neutron scattering data requires the knowledge of the inelastic resolution function. The inelastic resolution function of the time-of-flight spectrometer IN5/ILL has been measured by exploiting the sharp resonances of the roton and maxon excitations in superfluid sup 4 He for the two respective (q,omega) values. The calculated inelastic resolution function for three different instrumental setups is compared to the experimentally determined resolution function. The agreement between simulation and experimental data is excellent, allowing us in principle to extrapolate the simulations and thus to determine the resolution function in the whole accessible dynamic range of IN5 or any other time-of-flight spectrometer. (orig.)

Measurement and calculation of cosmic radiation exposure during a pole-to-pole flight sequence

International Nuclear Information System (INIS)

Taylor, Graeme C.; Ojjeh, Captain Aziz

2010-01-01

Cosmic ray dosimetry measurements were carried out on board a Global Express business jet operated by TAG Aviation (UK) during a pole-to-pole flight sequence that took place in November 2008. One Hawk TEPC and two EPDN2s were flown, and the TEPC measurements compared to calculated values from the route dose codes AVIDOS, CARI 6M, EPCARD versions 3.2 and 3.34, QARM and SIEVERT (online version). The largest difference between measured and calculated doses for the total flight sequence was found to be 13%. Agreement between the readings of the TEPC and the EPDN2s (once a calibration factor from the CERN High Energy Reference Field had been applied) was reasonably good given the relatively large uncertainties associated with the EPDN2 measurements.

Time of flight measurements based on FPGA using a breast dedicated PET

International Nuclear Information System (INIS)

Aguilar, A; García-Olcina, R; Martos, J; Soret, J; Torres, J; Benlloch, J M; González, A J; Sánchez, F

2014-01-01

In this work the implementation of a Time-to-Digital Converter (TDC) using a Nutt delay line FPGA-based and applied on a Positron Emission Tomography (PET) device is going to be presented in order to check the system's suitability for Time of Flight (TOF) measurements. In recent years, FPGAs have shown great advantages for precise time measurements in PET. The architecture employed for these measurements is described in detail. The system developed was tested on a dedicated breast PET prototype, composed of LYSO crystals and Positive Sensitive Photomultipliers (PSPMTs). Two distinct experiments were carried out for this purpose. In the first test, system linearity was evaluated in order to calibrate the time measurements, providing a linearity error of less than 2% and an average time resolution of 1.4 ns FWHM. The second set of measurements tested system resolution, resulting in a FWHM as good as 1.35 ns. The results suggest that the coincidence window for the current PET can be reduced in order to minimize the random events and thus, achieve better image quality

Realization and Measurement of a Wearable Radio Frequency Identification Tag Antenna

Directory of Open Access Journals (Sweden)

Shudao ZHOU

2014-06-01

Full Text Available The realization and measurements of a wearable Radio Frequency Identification tag antenna which achieves good simulation results in the Ultimate High Frequency band under the standard of the United States in design procedures is presented. The wearable tag antenna is constructed using a flexible substrate, on whose surface the antenna patch is adhered. A bowtie shape is chosen as the geometry of the antenna patch because of its large bandwidth that brings to the tag and its simple structure. The substrate of the tag antenna is realized using a foam material while the patch on the substrate surface is cut out from copper foil tape. Then, the impedance of the realized tag antenna is extracted from S parameters which are measured with a vector network analyzer with a coaxial fixture. Finally, the radiation pattern of the tag is characterized by normalized reading distances of different directions of the antenna integrated with a microchip, thus indicating the validity of the realized tag antenna.

A Measurement of $R_b$ using a Lifetime-Mass Tag

CERN Document Server

Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Miquel, R; Mir, L M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Becker, U; Bazarko, A O; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Ghete, V M; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Coyle, P; Diaconu, C A; Etienne, F; Konstantinidis, N P; Leroy, O; Motsch, F; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Berlich, R; Blum, Walter; Brown, D; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Schune, M H; Simion, S; Tournefier, E; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; Gao, Y S; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zobernig, G

1997-01-01

ALEPH's published measurement of $R_b$ using a lifetime tag, is updated using the full LEP~1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the b/c hadron mass difference. Furthermore, the algorithm used to reconstruct the event primary vertex is designed so as to reduce correlations between the two hemispheres of an event. The value of $R_b$ is measured to be $0.2167\\pm 0.0011{\\mathrm (stat)}\\pm 0.0013{\\mathrm (syst)}$.

Investigation of time-of-flight lifetime measurement methods of charged π mesons at the Phasotron of JINR

International Nuclear Information System (INIS)

Evtukhovich, P.G.; Kallies, W.; Kononenko, G.A.; Samojlov, V.N.; Sapogov, A.S.

2003-01-01

The methods of time-of-flight lifetime measurement of charged π mesons that have been realized at the Phasotron of the Laboratory of Nuclear Problems (LNP) of JINR are described. The distinguishing feature of the given methods consists in the use of the following technique: 1) time-of-flight investigation of particle beam composition for relatively long flight path (base); 2) an optimal choice (for the given base) of beam geometry under investigation; 3) monitoring of π-meson momentum along the whole explored trajectory; 4) the use of high resolution scintillation detectors. This technique together with correct mathematical calculations provided a possibility of controlling the influence of main systematic factors on the precision of the data obtained. These methods allow one to compute an amount of sampling that requisites a given precision based on preliminary evaluations of random and systematic errors of charged π-mesons measured lifetime

Modeling of a 3D CMOS sensor for time-of-flight measurements

Science.gov (United States)

Kuhla, Rico; Hosticka, Bedrich J.; Mengel, Peter; Listl, Ludwig

2004-02-01

A solid state 3D-CMOS camera system for direct time-of-flight image acquisition consisting of a CMOS imaging sensor, a laser diode module for active laser pulse illumination and all optics for image forming is presented, including MDSI & CDS algorithms for time-of-flight evaluation from intensity imaging. The investigation is carried out using ideal and real signals. For real signals the narrow infrared laser pulse of the laser diode module and the shutter function of the sensors column circuit were sampled by a new sampling procedure. A discrete sampled shutter function was recorded by using the impulse response of a narrow pulse of FWHM=50ps and an additional delay block with step size of Δτ = 0.25ns. A deterministic system model based on LTI transfer functions was developed. The visual shutter windows give a good understanding of differences between ideal and real output functions of measurement system. Simulations of shutter and laser pulse brought out an extended linear delay domain from MDSI. A stochastic model for the transfer function and photon noise in time domain was developed. We used the model to investigate noise in variation the laser pulse shutter configuration.

Response probability and response time: a straight line, the Tagging/Retagging interpretation of short term memory, an operational definition of meaningfulness and short term memory time decay and search time.

Science.gov (United States)

Tarnow, Eugen

2008-12-01

The functional relationship between correct response probability and response time is investigated in data sets from Rubin, Hinton and Wenzel, J Exp Psychol Learn Mem Cogn 25:1161-1176, 1999 and Anderson, J Exp Psychol [Hum Learn] 7:326-343, 1981. The two measures are linearly related through stimulus presentation lags from 0 to 594 s in the former experiment and for repeated learning of words in the latter. The Tagging/Retagging interpretation of short term memory is introduced to explain this linear relationship. At stimulus presentation the words are tagged. This tagging level drops slowly with time. When a probe word is reintroduced the tagging level has to increase for the word to be properly identified leading to a delay in response time. The tagging time is related to the meaningfulness of the words used-the more meaningful the word the longer the tagging time. After stimulus presentation the tagging level drops in a logarithmic fashion to 50% after 10 s and to 20% after 240 s. The incorrect recall and recognition times saturate in the Rubin et al. data set (they are not linear for large time lags), suggesting a limited time to search the short term memory structure: the search time for recall of unusual words is 1.7 s. For recognition of nonsense words the corresponding time is about 0.4 s, similar to the 0.243 s found in Cavanagh (1972).

Accurate Mass GC/LC-Quadrupole Time of Flight Mass Spectrometry Analysis of Fatty Acids and Triacylglycerols of Spicy Fruits from the Apiaceae Family

Directory of Open Access Journals (Sweden)

Thao Nguyen

2015-12-01

Full Text Available The triacylglycerol (TAG structure and the regio-stereospecific distribution of fatty acids (FA of seed oils from most of the Apiaceae family are not well documented. The TAG structure ultimately determines the final physical properties of the oils and the position of FAs in the TAG molecule affects the digestion; absorption and metabolism; and physical and technological properties of TAGs. Fixed oils from the fruits of dill (Anethum graveolens, caraway (Carum carvi, cumin (Cuminum cyminum, coriander (Coriandrum sativum, anise (Pimpinella anisum, carrot (Daucus carota, celery (Apium graveolens, fennel (Foeniculum vulgare, and Khella (Ammi visnaga, all from the Apiaceae family, were extracted at room temperature in chloroform/methanol (2:1 v/v using percolators. Crude lipids were fractionated by solid phase extraction to separate neutral triacylglycerols (TAGs from other lipids components. Neutral TAGs were subjected to transesterification process to convert them to their corresponding fatty acids methyl esters (FAMES using 1% boron trifluoride (BF3 in methanol. FAMES were analyzed by gas chromatography-quadrupole time of flight (GC-QTOF mass spectrometry. Triglycerides were analyzed using high performance liquid chromatography-quadrupole time of flight (LC-QTOF mass spectrometry. Petroselinic acid was the major fatty acid in all samples ranging from 57% of the total fatty acids in caraway up to 82% in fennel. All samples contained palmitic (16:0, palmitoleic (C16:1n-9, stearic (C18:0, petroselinic (C18:1n-12, linoleic (C18:2n-6, linolinic (18:3n-3, and arachidic (C20:0 acids. TAG were analyzed using LC-QTOF for accurate mass identification and mass spectrometry/mass spectrometry (MS/MS techniques for regiospesific elucidation of the identified TAGs. Five major TAGs were detected in all samples but with different relative concentrations in all of the tested samples. Several other TAGs were detected as minor components and were present in some

Flow-Tagging Velocimetry for Hypersonic Flows Using Fluorescence of Nitric Oxide

Science.gov (United States)

Danehy, P. M.; OByrne, S.; Houwing, A. F. P.

2001-01-01

We investigate a new type of flow-tagging velocimetry technique for hypersonic flows. The technique involves exciting a thin line of nitric oxide molecules with a laser beam and then, after some delay, acquiring an image of the displaced line. One component of velocity is determined from the time of flight. This method is applied to measure the velocity profile in a Mach 8.5 laminar, hypersonic boundary layer in the Australian National Universities T2 free-piston shock tunnel. The velocity is measured with an uncertainty of approximately 2%. Comparison with a CFD simulation of the flow shows reasonable agreement.

ALICE Time of Flight Module

CERN Multimedia

The Time-Of-Flight system of ALICE consists of 90 such modules, each containing 15 or 19 Multigap Resistive Plate Chamber (MRPC) strips. This detector is used for identification of charged particles. It measures with high precision (50 ps) the time of flight of charged particles and therefore their velocity. The curvature of the particle trajectory inside the magnetic field gives the momentum, thus the particle mass is calculated and the particle is identified The MRPC is a stack of resistive glass plates, separated from each other by nylon fishing line. The mass production of the chambers (~1600, covering a surface of 150 m2) was done at INFN Bologna, while the first prototypes were bult at CERN.

Measurements of the plasma density in the FTU tokamak by a pulsed time-of-flight X-wave refractometer

International Nuclear Information System (INIS)

Petrov, V. G.; Petrov, A. A.; Malyshev, A. Yu.; De Benedetti, M.; Tudisco, O.

2008-01-01

On-line control over the plasma density in tokamaks (especially, in long-term discharges) requires reliable measurements of the averaged plasma density. For this purpose, a new method of density measurements-a pulsed time-of-flight plasma refractometry-was developed and tested in the T-11M tokamak. This method allows one to determine the averaged density from the measured time delay of nanosecond microwave pulses propagating through the plasma. For an O-wave, the measured time delay is proportional to the line-averaged density and is independent of the density profile (f>>f p ) τ o ∼ k o 1/f 2 ∫ l N(x)dx. Here, f is the frequency of the probing wave, f p is the plasma frequency, l= 4 a is the path length for two-pass probing in the equatorial plane, a is the plasma minor radius, k O and k X are numerical factors, f c is the electron-cyclotron frequency at the axis of the plasma column, and f p >>f c , f. Measurements of the time delay provide the same information as plasma interferometry, though they do no employ the effect of interference. When the conditions f p >>f c , f are not satisfied, the measured time delay depends on the shape of the density profile. In this case, in order to determine the average density regardless of the density profile, it is necessary to perform simultaneous measurements at several probing frequencies in order to determine the average density. In ITER (Bt ∼ 5T), a spectral window between the lower and upper cutoff frequencies in the range of 50-100 GHz can be used for pulsed time-of-flight X-wave refractometry. This appreciably simplifies the diagnostics and eliminates the problem of the first mirror. In this paper, the first results obtained in the FTU tokamak with a prototype of the ITER pulsed time-of-flight refractometer are presented. The geometry and layout of experiments similar to the planned ITER experiments are described. The density measured by pulsed time-of-flight refractometry is shown to agree well with the

An improvement of isochronous mass spectrometry: Velocity measurements using two time-of-flight detectors

International Nuclear Information System (INIS)

Shuai, P.; Xu, X.; Zhang, Y.H.; Xu, H.S.; Litvinov, Yu. A.; Wang, M.

2016-01-01

Isochronous mass spectrometry (IMS) in storage rings is a powerful tool for mass measurements of exotic nuclei with very short half-lives down to several tens of microseconds, using a multicomponent secondary beam separated in-flight without cooling. However, the inevitable momentum spread of secondary ions limits the precision of nuclear masses determined by using IMS. Therefore, the momentum measurement in addition to the revolution period of stored ions is crucial to reduce the influence of the momentum spread on the standard deviation of the revolution period, which would lead to a much improved mass resolving power of IMS. One of the proposals to upgrade IMS is that the velocity of secondary ions could be directly measured by using two time-of-flight (double TOF) detectors installed in a straight section of a storage ring. In this paper, we outline the principle of IMS with double TOF detectors and the method to correct the momentum spread of stored ions.

The IRK time-of-flight facility for measurements of double-differential neutron emission cross sections

International Nuclear Information System (INIS)

Pavlik, A.; Priller, A.; Steier, P.; Vonach, H.; Winkler, G.

1994-01-01

In order to improve the present experimental data base of energy- and angle-differential neutron emission cross sections at 14 MeV incident-neutron energy, a new time-of-flight (TOF) facility was installed at the Institut fuer Radiumforschung und Kernphysik (IRK), Vienna. The set-up was particularly designed to more precisely measure the high-energy part of the secondary neutron spectra and consists of three main components: (1) a pulsed neutron generator of Cockcroft-Walton type producing primary neutrons via the T(d,n)-reaction, (2) a tube system which can be evacuated containing the neutron flight path, the sample, collimators and the sample positioning system, and (3) the neutron detectors with the data acquisition equipment. Removing the air along the neutron flight path results in a drastic suppression of background due to air-scattered neutrons in the spectrum of the secondary neutrons. For every secondary neutron detected in the main detector, the time-of-flight, the pulse-shape information and the recoil energy are recorded in list-mode via a CAMAC system connected to a PDP 11/34 on-line computer. Using a Micro VAX, the multiparameter data are sorted and reduced to double-differential cross sections

Rocket-borne time-of-flight mass spectrometry

Science.gov (United States)

Reiter, R. F.

1976-01-01

Theoretical and numerical analyses are made of planar, cylindrical and spherical-electrode two-field time-of-flight mass spectrometers in order to optimize their operating conditions. A method is introduced which can improve the resolving power of these instruments by a factor of 7.5. Potential barrier gating in time-of-flight mass spectrometers is also analyzed. Experimental studies of a miniature cylindrical-electrode and a hemispherical-electrode time-of-flight mass spectrometer are presented. Their sensitivity and ability to operate at D-region pressures with an open source make them ideal instruments for D-region ion composition measurements. A sounding rocket experiment package carrying a cylindrical electrode time-of-flight mass spectrometer was launched. The data indicate that essentially 100% of the positive electric charge on positive ions is carried by ions with mass-to-charge ratios greater than 500 below an altitude of 92 km. These heavy charge carriers were present at altitudes up to about 100 km.

Rocket-borne time-of-flight mass spectrometry

International Nuclear Information System (INIS)

Reiter, R.F.

1976-08-01

Theoretical and numerical analyses are made of planar-, cylindrical- and spherical-electrode two-field time-of-flight mass spectrometers in order to optimize their operating conditions. A method is introduced which can improve the resolving power of these instruments by a factor of 7.5. Potential barrier gating in time-of-flight mass spectrometers is also analyzed. Experimental studies of a miniature cylindrical-electrode and a hemispherical-electrode time-of-flight mass spectrometer are presented. Their sensitivity and ability to operate at D-region pressures with an open source make them ideal instruments for D-region ion composition measurements. A sounding rocket experiment package carrying a cylindrical electrode time-of-flight mass spectrometer was launched. The data indicate that essentially 100% of the positive electric charge on positive ions is carried by ions with mass-to-charge ratios greater than 500 below an altitude of 92 km. These heavy charge carriers were present at altitudes up to about 100 km

Data for analysis of mannose-6-phosphate glycans labeled with fluorescent tags.

Science.gov (United States)

Kang, Ji-Yeon; Kwon, Ohsuk; Gil, Jin Young; Oh, Doo-Byoung

2016-06-01

Mannose-6-phosphate (M-6-P) glycan plays an important role in lysosomal targeting of most therapeutic enzymes for treatment of lysosomal storage diseases. This article provides data for the analysis of M-6-P glycans by high-performance liquid chromatography (HPLC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The identities of M-6-P glycan peaks in HPLC profile were confirmed by measuring the masses of the collected peak eluates. The performances of three fluorescent tags (2-aminobenzoic acid [2-AA], 2-aminobenzamide [2-AB], and 3-(acetyl-amino)-6-aminoacridine [AA-Ac]) were compared focusing on the analysis of bi-phosphorylated glycan (containing two M-6-Ps). The bi-phosphorylated glycan analysis is highly affected by the attached fluorescent tag and the hydrophilicity of elution solvent used in HPLC. The data in this article is associated with the research article published in "Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans" (Kang et al., 2016 [1]).

Improved measurement linearity and precision for AMCW time-of-flight range imaging cameras.

Science.gov (United States)

Payne, Andrew D; Dorrington, Adrian A; Cree, Michael J; Carnegie, Dale A

2010-08-10

Time-of-flight range imaging systems utilizing the amplitude modulated continuous wave (AMCW) technique often suffer from measurement nonlinearity due to the presence of aliased harmonics within the amplitude modulation signals. Typically a calibration is performed to correct these errors. We demonstrate an alternative phase encoding approach that attenuates the harmonics during the sampling process, thereby improving measurement linearity in the raw measurements. This mitigates the need to measure the system's response or calibrate for environmental changes. In conjunction with improved linearity, we demonstrate that measurement precision can also be increased by reducing the duty cycle of the amplitude modulated illumination source (while maintaining overall illumination power).

High resolution time-of-flight measurements in small and large scintillation counters

International Nuclear Information System (INIS)

D'Agostini, G.; Marini, G.; Martellotti, G.; Massa, F.; Rambaldi, A.; Sciubba, A.

1981-01-01

In a test run, the experimental time-of-flight resolution was measured for several different scintillation counters of small (10 x 5 cm 2 ) and large (100 x 15 cm 2 and 75 x 25 cm 2 ) area. The design characteristics were decided on the basis of theoretical Monte Carlo calculations. We report results using twisted, fish-tail, and rectangular light- guides and different types of scintillator (NE 114 and PILOT U). Time resolution up to approx. equal to 130-150 ps fwhm for the small counters and up to approx. equal to 280-300 ps fwhm for the large counters were obtained. The spatial resolution from time measurements in the large counters is also reported. The results of Monte Carlo calculations on the type of scintillator, the shape and dimensions of the light-guides, and the nature of the external wrapping surfaces - to be used in order to optimize the time resolution - are also summarized. (orig.)

Timing properties of a time-of-flight detector

International Nuclear Information System (INIS)

Nakagawa, Takahide; Yuasa-Nakagawa, Keiko.

1989-01-01

The time resolution of a time-of-flight (T.O.F.) detector which consists of a channel plate detector (CPD) with a central hole and a surface barrier detector (SBD) was measured. A time resolution of 80 psec fwhm was obtained for 8.78 MeV alpha particles. The influence on fast timing of the SBD of alpha particles was carefully studied. The plasma delay time and time resolution of the SBD were found to strongly depend on the electric field strength and properties of the SBD. (author)

Measurement of Rb Using a Vertex Mass Tag

International Nuclear Information System (INIS)

Steiner, R.; Benvenuti, A.C.; Coller, J.A.; Hedges, S.J.; Johnson, A.S.; Shank, J.T.; Whitaker, J.S.; Allen, N.J.; Cotton, R.; Dervan, P.J.; Hasan, A.; McKemey, A.K.; Watts, S.J.; Caldwell, D.O.; Lu, A.; Yellin, S.J.; Cavalli-Sforza, M.; Coyne, D.G.; Fernandez, J.P.; Liu, X.; Reinertsen, P.L.; Schalk, T.; Schumm, B.A.; DOliveira, A.; Johnson, R.A.; Meadows, B.T.; Nussbaum, M.; Dima, M.; Harton, J.L.; Smy, M.B.; Staengle, H.; Wilson, R.J.; Baranko, G.; Fahey, S.; Fan, C.; Krishna, N.M.; Lauber, J.A.; Nauenberg, U.; Wagner, D.L.; Bazarko, A.O.; Bolton, T.; Rowson, P.C.; Shaevitz, M.H.; Camanzi, B.; Mazzucato, E.; Piemontese, L.; Calcaterra, A.; De Sangro, R.; Peruzzi, I.; Piccolo, M.; Eisenstein, B.I.; Gladding, G.; Karliner, I.; Shapiro, G.; Steiner, H.; Bardon, O.; Burrows, P.N.; Busza, W.; Cowan, R.F.; Dong, D.N.; Fero, M.J.; Gonzalez, S.; Kendall, H.W.; Lath, A.; Lia, V.; Osborne, L.S.; Quigley, J.; Taylor, F.E.; Torrence, E.; Verdier, R.; Williams, D.C.

1998-01-01

We report a new measurement of R b =Γ Z 0 →bbar b /Γ Z 0 →hadrons using a double tag technique, where the b hemisphere selection is based on the reconstructed mass of the B hadron decay vertex. The measurement was performed using a sample of 130x10 3 hadronic Z 0 events, collected with the SLD detector at SLC. The method utilizes the 3D vertexing abilities of the CCD pixel vertex detector and the small stable SLC beams to obtain a high b -tagging efficiency and purity. We obtain R b =0.2142±0.0034(stat) ±0.0015(syst)±0.0002( R c ) . copyright 1998 The American Physical Society

Time-of-flight experiments using a pseudo-statistical chopper

International Nuclear Information System (INIS)

Aizawa, Otohiko; Kanda, Keiji

1975-01-01

A ''pseudo-statistical'' chopper was manufactured and used for the experiments on neutron transmission and scattering. The characteristics of the chopper and the experimental results are discussed in comparison with those in the time-of-flight technique using a conventional chopper. Which of the two methods is superior depends on the form of the time-of-flight distribution to be measured. Pseudo-statistical pulsing may be especially advantageous for scattering experiments with single or a few-line time-of-flight spectrum. (auth.)

Time-of-flight measurements of the plasma density in the T-11M tokamak

International Nuclear Information System (INIS)

Petrov, V. G.; Petrov, A. A.; Malyshev, A. Yu.; Markov, V. K.; Babarykin, A. V.

2006-01-01

The average plasma density in the T-11M tokamak is determined by means of an O-mode time-of-flight refractometer measuring the propagation time τ of microwave pulses through the plasma. Since the front duration τ fr of these pulses is shorter than 2 ns, filtering the measured signal cannot reduce the signal-to-noise ratio below a certain level. This circumstance impedes the use of this diagnostics in larger devices, where the signals may be substantially attenuated because of the larger chamber size and larger waveguide losses. There are several ways to overcome these difficulties: to raise the microwave power, to increase the sensitivity of the receivers, etc. In this paper, a technique is described that is based on the differential method for determining the propagation time of a microwave signal through the plasma. In this method, the plasma is probed by two continuous microwaves with close frequencies and the phase difference between them Δφ 12 is measured. As long as the condition Δφ 12 < 2π is satisfied, the measurements are unambiguous, because there are no phase jumps by a value multiple of 2π, as is usually the case in conventional interferometers at an increased level of MHD activity, in regimes with a rapid density growth, etc. This method allows the signal to be filtered, thereby ensuring an appreciable improvement in the signal-to-noise ratio in comparison with the pulsed methods. The first measurements of the average density along the +3-cm chord were performed with the help of this new differential time-of-flight refractometer in the T-11M tokamak. The refractometry data agree well with the interferometric data and are used to recover the plasma-density profile

First Isochronous Time-of-Flight Mass Measurements of Short-Lived Projectile Fragments in the ESR

International Nuclear Information System (INIS)

Stadlmann, J.; Geissel, H.; Hausmann, M.; Nolden, F.; Radon, T.; Schatz, H.; Scheidenberger, C.; Attallah, F.; Beckert, K.; Bosch, F.; Falch, M.; Franczak, B.; Franzke, B.; Kerscher, Th.; Klepper, O.; Kluge, H.J.; Kozhuharov, C.; Loebner, K.E.G.; Muenzenberg, G.; Novikov, Yu.N.; Steck, M.; Sun, Z.; Suemmerer, K.; Weick, H.; Wollnik, H.

2000-01-01

A new method for precise mass measurements of short-lived hot nuclei is presented. These nuclei were produced via projectile fragmentation, separated with the FRS and injected into the storage ring ESR being operated in the isochronous mode. The revolution time of the ions is measured with a time-of-flight detector sensitive to single particles. This new method allows access to exotic nuclei with half-lives in the microsecond region. First results from this novel method obtained with measurements on neutron-deficient fragments of a chromium primary beam with half-lives down to 50 ms are reported. A precision of deltam/m ≤ 5 · 10 -6 has been achieved

Ion microtomography using ion time-of-flight

International Nuclear Information System (INIS)

Roberts, M.L.; Heikkinen, D.W.; Proctor, I.D.; Pontau, A.E.; Olona, G.T.; Felter, T.E.; Morse, D.H.; Hess, B.V.

1992-01-01

We have developed and are in the process of testing an ion time-of-flight (TOF) detector system for use in our ion microtomography measurements. Using TOF, ion energy is determined by measurement of the ion's flight time over a certain path length. For ion microtomography, the principle advantage of TOF analysis is that ion count rates of several hundred thousand counts per second can be achieved as compared to a limit of about ten thousand ions per second when using a solid-state silicon surface barrier detector and associated electronics. This greater than 10 fold increase in count rate correspondingly shortens sample analysis time or increases the amount of data that can be collected on a given sample. Details of the system and progress to date are described

Time coder for slow neutron time-of-flight spectrometer

International Nuclear Information System (INIS)

Grashilin, V.A.; Ofengenden, R.G.

1988-01-01

Time coder for slow neutron time-of-flight spectrometer is described. The time coder is of modular structure, is performed in the CAMAC standard and operates on line with DVK-2 computer. The main coder units include supporting generator, timers, time-to-digital converter, memory unit and crate controller. Method for measuring background symmetrically to the effect is proposed for a more correct background accounting. 4 refs.; 1 fig

Time of flight measurements of unirradiated and irradiated nuclear graphite under cyclic compressive load

Energy Technology Data Exchange (ETDEWEB)

Bodel, W., E-mail: william.bodel@hotmail.com [Nuclear Graphite Research Group, The University of Manchester (United Kingdom); Atkin, C. [Health and Safety Laboratory, Buxton (United Kingdom); Marsden, B.J. [Nuclear Graphite Research Group, The University of Manchester (United Kingdom)

2017-04-15

The time-of-flight technique has been used to investigate the stiffness of nuclear graphite with respect to the grade and grain direction. A loading rig was developed to collect time-of-flight measurements during cycled compressive loading up to 80% of the material's compressive strength and subsequent unloading of specimens along the axis of the applied stress. The transmission velocity (related to Young's modulus), decreased with increasing applied stress; and depending on the graphite grade and orientation, the modulus then increased, decreased or remained constant upon unloading. These tests were repeated while observing the microstructure during the load/unload cycles. Initial decreases in transmission velocity with compressive load are attributed to microcrack formation within filler and binder phases. Three distinct types of behaviour occur on unloading, depending on the grade, irradiation, and loading direction. These different behaviours can be explained in terms of the material microstructure observed from the microscopy performed during loading.

A time-of-flight system for precise measurements of a relativistic charged particle beam momentum

International Nuclear Information System (INIS)

Avramenko, S.A.; Belikov, Yu.A.; Golokhvastov, A.I.; Lukstin'sh, Yu.; Man'yakov, P.K.; Rukoyatkin, P.A.; Khorozov, S.A.

1996-01-01

A time-of-flight system with a time resolution (σ) about 100 ps is described. The methods for the calibration, stability verification and the method for the time resolution evaluation in conditions of a nonmonochromatic beam are discussed especially. The system was applied in charge exchange ( 3 H, 3 He) experiments with the GIBS spectrometer for a measurement of 3 H-nuclei momenta at 2 GeV/c per nucleon with a precision about 0.2%. (author). 4 refs., 7 figs., 1 tab

Activity on improving performance of time-of-flight detector at CDF

International Nuclear Information System (INIS)

Menzione, A.; Cerri, C.; Vataga, E.; Prokoshin, F.; Tokar, S.

2002-01-01

The paper describes activity on improving the time resolution of the Time-of-Flight detector at CDF. The main goal of the detector is the identification of kaons and pions for b-quark (B-meson) flavour tagging. Construction of the detector has been described as well as proposals on detector design changes to improve its time resolution. Monte Carlo simulation of the detector response to MIP was performed. The results of the simulation showed that the proposed modifications (at least with currently available materials) bring modest or no improvement of the detector time resolution. An automated set-up was assembled to test and check out the changes in the electronic readout system of the detector. Sophisticated software has been developed for this set-up to provide control of the system as well as processing and presentation of data from the detector. This software can perform various tests using different implementations of the hardware set-up

Data for analysis of mannose-6-phosphate glycans labeled with fluorescent tags

Directory of Open Access Journals (Sweden)

Ji-Yeon Kang

2016-06-01

Full Text Available Mannose-6-phosphate (M-6-P glycan plays an important role in lysosomal targeting of most therapeutic enzymes for treatment of lysosomal storage diseases. This article provides data for the analysis of M-6-P glycans by high-performance liquid chromatography (HPLC and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF mass spectrometry. The identities of M-6-P glycan peaks in HPLC profile were confirmed by measuring the masses of the collected peak eluates. The performances of three fluorescent tags (2-aminobenzoic acid [2-AA], 2-aminobenzamide [2-AB], and 3-(acetyl-amino-6-aminoacridine [AA-Ac] were compared focusing on the analysis of bi-phosphorylated glycan (containing two M-6-Ps. The bi-phosphorylated glycan analysis is highly affected by the attached fluorescent tag and the hydrophilicity of elution solvent used in HPLC. The data in this article is associated with the research article published in “Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans” (Kang et al., 2016 [1].

Time-of-flight scattering and recoiling spectrometry

International Nuclear Information System (INIS)

Rabalais, J.W.

1991-01-01

Ion scattering and recoiling spectrometry consists of directing a collimated beam of monoenergetic ions towards a surface and measuring the flux of scattered and recoiled particles from this surface. When the neutral plus ion flux is velocity selected by measuring the flight times from the sample to the detector, the technique is called time-of-flight scattering and recoiling spectrometry (TOF-SARS). TOF-SARS is capable of (1) surface elemental analysis by applying classical mechanics to the velocities of the particles, (2) surface structural analysis by monitoring the angular anisotropies in the particle flux, and (3) ion-surface electron exchange probabilities by analysis of the ion/neutral fractions in the particle flux. Examples of these three areas are presented herein

TORCH—a Cherenkov based time-of-flight detector

Energy Technology Data Exchange (ETDEWEB)

Dijk, M.W.U. van, E-mail: m.vandijk@bristol.ac.uk [H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Brook, N.H. [H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Castillo García, L. [European Organisation for Nuclear Research (CERN), CH-1211 Geneva 23 (Switzerland); Laboratory for High Energy Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Cowie, E.N.; Cussans, D. [H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); D' Ambrosio, C. [European Organisation for Nuclear Research (CERN), CH-1211 Geneva 23 (Switzerland); Fopma, J. [Denys Wilkinson Laboratory, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Forty, R.; Frei, C. [European Organisation for Nuclear Research (CERN), CH-1211 Geneva 23 (Switzerland); Gao, R. [Denys Wilkinson Laboratory, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Gys, T. [European Organisation for Nuclear Research (CERN), CH-1211 Geneva 23 (Switzerland); Harnew, N.; Keri, T. [Denys Wilkinson Laboratory, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Piedigrossi, D. [European Organisation for Nuclear Research (CERN), CH-1211 Geneva 23 (Switzerland)

2014-12-01

TORCH is an innovative high-precision time-of-flight system to provide particle identification in the difficult intermediate momentum region up to 10 GeV/c. It is also suitable for large-area applications. The detector provides a time-of-flight measurement from the imaging of Cherenkov photons emitted in a 1 cm thick quartz radiator. The photons propagate by total internal reflection to the edge of the quartz plate and are then focused onto an array of photon detectors at the periphery. A time-of-flight resolution of about 10–15 ps per incident charged particle needs to be achieved to allow a three sigma kaon-pion separation up to 10 GeV/c momentum for the TORCH located 9.5 m from the interaction point. Given ∼30 detected photons per incident charged particle, this requires measuring the time-of-arrival of individual photons to about 70 ps. This paper will describe the design of a TORCH prototype involving a number of ground-breaking and challenging techniques.

Doppler time-of-flight imaging

KAUST Repository

Heide, Felix

2015-07-30

Over the last few years, depth cameras have become increasingly popular for a range of applications, including human-computer interaction and gaming, augmented reality, machine vision, and medical imaging. Many of the commercially-available devices use the time-of-flight principle, where active illumination is temporally coded and analyzed on the camera to estimate a per-pixel depth map of the scene. In this paper, we propose a fundamentally new imaging modality for all time-of-flight (ToF) cameras: per-pixel velocity measurement. The proposed technique exploits the Doppler effect of objects in motion, which shifts the temporal frequency of the illumination before it reaches the camera. Using carefully coded illumination and modulation frequencies of the ToF camera, object velocities directly map to measured pixel intensities. We show that a slight modification of our imaging system allows for color, depth, and velocity information to be captured simultaneously. Combining the optical flow computed on the RGB frames with the measured metric axial velocity allows us to further estimate the full 3D metric velocity field of the scene. We believe that the proposed technique has applications in many computer graphics and vision problems, for example motion tracking, segmentation, recognition, and motion deblurring.

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, A.V.; Veldhuizen, E.J. van; Westerberg, L.; Lyapin, V.G.; Aleklett, K.; Loveland, W.; Bondorf, J.; Jakobsson, B.; Whitlow, H.J.; El Bouanani, M

2000-10-01

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate (MCP) time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of {approx}35 keV/nucleon from the interactions of 400 MeV/nucleon {sup 16}O with {sup nat}Xe gas targets.

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products

International Nuclear Information System (INIS)

Kuznetsov, A.V.; Loveland, W.; Jakobsson, B.; Whitlow, H.J.; Bouanani, M. El; Univ. of North Texas, Denton, TX

2000-01-01

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of ∼ 35 keV/nucleon from the interactions of 400 MeV/nucleon 16 O with nat Xe gas targets

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, A.V. [V.G.Khlopin Radium Institute, St. Petersburg (Russian Federation); Uppsala Univ. (Sweden). The Svedberg Lab.; Veldhuizen, E.J. van; Aleklett, K. [Uppsala Univ., (Sweden). Dept. of Radiation Sciences; Westerberg, L. [Uppsala University (Sweden). The Svedberg Lab.; Lyapin, V.G. [V.G.Khlopin Radium Institute, St. Petersburg (Russian Federation); Loveland, W. [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry; Bondorf, J. [Niels Bohr Inst., Copenhagen (Denmark); Jakobsson, B. [Lund Univ. (Sweden). Dept. of Physics; Whitlow, H.J. [Lund Univ. (Sweden). Dept. of Nuclear Physics; Bouanani, M. El [Lund Univ. (Sweden). Dept. of Nuclear Physics; Univ. of North Texas, Denton, TX (United States). Dept. of Physics

2000-07-01

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of {approx} 35 keV/nucleon from the interactions of 400 MeV/nucleon {sup 16}O with {sup nat} Xe gas targets.

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products

International Nuclear Information System (INIS)

Kuznetsov, A.V.; Veldhuizen, E.J. van; Westerberg, L.; Lyapin, V.G.; Aleklett, K.; Loveland, W.; Bondorf, J.; Jakobsson, B.; Whitlow, H.J.; El Bouanani, M.

2000-01-01

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate (MCP) time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of ∼35 keV/nucleon from the interactions of 400 MeV/nucleon 16 O with nat Xe gas targets

A small sized time-of-flight mass spectrometer for simultaneous measurement of neutral and ionic species effusing from plasma, 1

International Nuclear Information System (INIS)

Horiuchi, Yukihiko

1986-01-01

A principle for simultaneous and real time measurement of neutral and ionic species effusing from plasma by using a time-of-flight mass spectrometer is proposed. A simple, small sized time-of-flight mass spectrometer combined with a dc glow discharge tube and an ion sampling electrode system for the simultaneous measurement on the basis of the proposed plinciple, has been constructed and tested. Details of the experimental setup including the geometry and the electronic hardware are described. It is shown that mass spectra of neutrals and ions from the positive column of the argon dc glow discharge are successfully observed on a single oscilloscope display. (author)

KELVIN rare gas time-of-flight program

International Nuclear Information System (INIS)

Vernon, M.

1981-03-01

The purpose of this appendix is to explain in detail the procedure for performing time-of-flight (TOF) calibration measurements. The result of the calibration measurements is to assign a correct length (L) to the path the molecules travel in a particular experimental configuration. In conjunction with time information (t) a velocity distribution (L/t) can then be determined. The program KELVIN is listed

Nuclear Forensics: Measurements of Uranium Oxides Using Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

Science.gov (United States)

2010-03-01

Isotope Ratio Analysis of Actinides , Fission Products, and Geolocators by High- efficiency Multi-collector Thermal Ionization Mass Spectrometry...Information, 1999. Hou, Xiaolin, and Per Roos. “ Critical Comparison of radiometric and Mass Spectrometric Methods for the Determination of...NUCLEAR FORENSICS: MEASUREMENTS OF URANIUM OXIDES USING TIME-OF-FLIGHT SECONDARY ION MASS

Time Series Neural Network Model for Part-of-Speech Tagging Indonesian Language

Science.gov (United States)

Tanadi, Theo

2018-03-01

Part-of-speech tagging (POS tagging) is an important part in natural language processing. Many methods have been used to do this task, including neural network. This paper models a neural network that attempts to do POS tagging. A time series neural network is modelled to solve the problems that a basic neural network faces when attempting to do POS tagging. In order to enable the neural network to have text data input, the text data will get clustered first using Brown Clustering, resulting a binary dictionary that the neural network can use. To further the accuracy of the neural network, other features such as the POS tag, suffix, and affix of previous words would also be fed to the neural network.

High resolution time-of-flight spectrometer for crossed molecular beam study of elementary chemical reactions

International Nuclear Information System (INIS)

Qiu Minghui; Che Li; Ren Zefeng; Dai Dongxu; Wang Xiuyan; Yang Xueming

2005-01-01

In this article, we describe an apparatus in our laboratory for investigating elementary chemical reactions using the high resolution time-of-flight Rydberg tagging method. In this apparatus, we have adopted a rotating source design so that collision energy can be changed for crossed beam studies of chemical reactions. Preliminary results on the HI photodissociation and the F atom reaction with H 2 are reported here. These results suggest that the experimental apparatus is potentially a powerful tool for investigating state-to-state dynamics of elementary chemical reactions

Organic scintillators response function modeling for Monte Carlo simulation of Time-of-Flight measurements

Energy Technology Data Exchange (ETDEWEB)

Carasco, C., E-mail: cedric.carasco@cea.fr [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 Saint-Paul-lez-Durance (France)

2012-07-15

In neutron Time-of-Flight (TOF) measurements performed with fast organic scintillation detectors, both pulse arrival time and amplitude are relevant. Monte Carlo simulation can be used to calculate the time-energy dependant neutron flux at the detector position. To convert the flux into a pulse height spectrum, one must calculate the detector response function for mono-energetic neutrons. MCNP can be used to design TOF systems, but standard MCNP versions cannot reliably calculate the energy deposited by fast neutrons in the detector since multiple scattering effects must be taken into account in an analog way, the individual recoil particles energy deposit being summed with the appropriate scintillation efficiency. In this paper, the energy response function of 2 Double-Prime Multiplication-Sign 2 Double-Prime and 5 Double-Prime Multiplication-Sign 5 Double-Prime liquid scintillation BC-501 A (Bicron) detectors to fast neutrons ranging from 20 keV to 5.0 MeV is computed with GEANT4 to be coupled with MCNPX through the 'MCNP Output Data Analysis' software developed under ROOT (). - Highlights: Black-Right-Pointing-Pointer GEANT4 has been used to model organic scintillators response to neutrons up to 5 MeV. Black-Right-Pointing-Pointer The response of 2 Double-Prime Multiplication-Sign 2 Double-Prime and 5 Double-Prime Multiplication-Sign 5 Double-Prime BC501A detectors has been parameterized with simple functions. Black-Right-Pointing-Pointer Parameterization will allow the modeling of neutron Time of Flight measurements with MCNP using tools based on CERN's ROOT.

Simple flight time calibration generator in PLL technique

International Nuclear Information System (INIS)

Lauch, J.

1975-01-01

Calibration and routine check-ups of flight time measuring systems can be carried out with the aid of defined flight time calibration spectra. This paper describes a simple flight time calibration generator capable of generating such calibration spectra in the form of line spectra or of a white spectrum. The flight time of the generator is adjustable in steps from 100 to 3,200 ns. The number of calibration lines can be set to 10 or to 20, resulting in line spacings ranging from 5 to 320 ns. The stop signals are generated by a crystal oscillator, the start signals are generated by a voltage-controlled oscillator locked in a phase control circuit. The start and stop rates can be adjusted in steps. (orig.) [de

A Time of flight spectrometer for measurements of double differential neutron scattering cross sections

International Nuclear Information System (INIS)

Padron, I.; Dominguez, O.; Sarria, P. Sandin, C.

1996-01-01

The time -of-Flight neutron spectrometry technique by associated particle method was improved using a D-T neutron generator at Laboratory of Nuclear Analysis. This technique was implemented for double differential cross section measurements and supported by the IAEA Project CUB/01/005. An stilbene scintillation detector (dia=100 mm, length=50 mm) was used as principal neutron detector detector and was situated outside a hole in the concrete wall. This way the fligth path was extended and the scattered neutron cone accurate collimated throught the 2 m concrete wall. For the associated particle α detection a thin plastic NE-102 scint illator was used, as well as, two scintilation detectors and a long counter for the neutron flux monitoring. In this TOF neutron spectrometer (3.40 m flight path) a 1.7 nseg. temporal resolution was obtained

Modeling the tagged-neutron UXO identification technique using the Geant4 toolkit

International Nuclear Information System (INIS)

Zhou, Y.; Zhu, X.; Wang, Y.; Mitra, S.

2012-01-01

It is proposed to use 14 MeV neutrons tagged by the associated particle neutron time-of-flight technique (APnTOF) to identify the fillers of unexploded ordnances (UXO) by characterizing their carbon, nitrogen and oxygen contents. To facilitate the design and construction of a prototype system, a preliminary simulation model was developed, using the Geant4 toolkit. This work established the toolkit environment for (a) generating tagged neutrons, (b) their transport and interactions within a sample to induce emission and detection of characteristic gamma-rays, and (c) 2D and 3D-image reconstruction of the interrogated object using the neutron and gamma-ray time-of-flight information. Using the modeling, this article demonstrates the novelty of the tagged-neutron approach for extracting useful signals with high signal-to-background discrimination of an object-of-interest from that of its environment. Simulations indicated that an UXO filled with the RDX explosive, hexogen (C 3 H 6 O 6 N 6 ), can be identified to a depth of 20 cm when buried in soil. (author)

On the use of the cold time-of-flight spectrometer in Studsvik for liquid 3He measurements

International Nuclear Information System (INIS)

Faak, Bjoern.

1989-01-01

The time-of-flight spectrometer for cold neutrons at the R2 reactor in Studsvik has been reconstructed. The design and the performance of the instrument are briefly described. Improvements required for measurement of the neutron scattering function of liquid 3 He are discussed. (author)

Energy and time of flight measurements of REX-ISOLDE stable beams using Si detectors

CERN Document Server

Cantero, E D; Fraser, M A; Lanaia, D; Sosa, A; Voulot, D; Zocca, F

2014-01-01

In this paper we present energy and time spectroscopy measurements for the stable beams of REX-ISOLDE obtained using Si detectors. By using an alpha source as a calibration reference, the absolute energy E of stable beam particles (A/q = 4) was determined in spectroscopy mode in the energy range 1 MeV < E < 8 MeV (0.30 MeV/u < E/A < 1.87 MeV/u). The time of flight of the beam particles (2.18 MeV/u < E/A < 2.27 MeV/u) was determined by installing identical Si detectors in two diagnostic boxes separated by 7.7 m. The results obtained with these two techniques are compared with the values obtained by dipole scans using a bending magnet. The measurements took place between January and February of 2013.

A description of the equipment for time-of-flight spectrum measurements on the fast reactor ZEBRA

International Nuclear Information System (INIS)

Gibson, I.H.; Jakeman, D.; Sanders, J.E.

1969-05-01

The pulsed source for the time-of-flight equipment consists of 14 MeV S-band linear electron accelerator, drift tube and water-cooled uranium-molybdenum alloy target installed on the ZEBRA lattice. Neutrons are extracted via a probe tube inserted into the core and an evacuated flight tube with counting stations at 50 m, 97 m and 200 m from the core centre. Two types of neutron detector are described and also the Perranti Argus 500 on-line computer which is used for data collection. The equipment is used for measuring the neutron energy spectra from the lowest energies up to about 1 MeV. (author)

Pulse Based Time-of-Flight Range Sensing.

Science.gov (United States)

Sarbolandi, Hamed; Plack, Markus; Kolb, Andreas

2018-05-23

Pulse-based Time-of-Flight (PB-ToF) cameras are an attractive alternative range imaging approach, compared to the widely commercialized Amplitude Modulated Continuous-Wave Time-of-Flight (AMCW-ToF) approach. This paper presents an in-depth evaluation of a PB-ToF camera prototype based on the Hamamatsu area sensor S11963-01CR. We evaluate different ToF-related effects, i.e., temperature drift, systematic error, depth inhomogeneity, multi-path effects, and motion artefacts. Furthermore, we evaluate the systematic error of the system in more detail, and introduce novel concepts to improve the quality of range measurements by modifying the mode of operation of the PB-ToF camera. Finally, we describe the means of measuring the gate response of the PB-ToF sensor and using this information for PB-ToF sensor simulation.

Neutron Time-Of-Flight (n_TOF) experiment

CERN Multimedia

Brugger, M; Kaeppeler, F K; Jericha, E; Cortes rossell, G P; Riego perez, A; Baccomi, R; Laurent, B G; Griesmayer, E; Leeb, H; Dressler, M; Cano ott, D; Variale, V; Ventura, A; Carrillo de albornoz trillo, A; Andrzejewski, J J; Pavlik, A F; Kadi, Y; Zanni vlastou, R; Krticka, M; Kokkoris, M; Praena rodriguez, A J; Cortes giraldo, M A; Perkowski, J; Losito, R; Audouin, L; Weiss, C; Tagliente, G; Wallner, A; Woods, P J; Mengoni, A; Guerrero sanchez, C G; Tain enriquez, J L; Vlachoudis, V; Calviani, M; Junghans, A R; Reifarth, R; Mendoza cembranos, E; Quesada molina, J M; Babiano suarez, V; Schumann, M D; Tsinganis, A; Rauscher, T; Calvino tavares, F; Mingrone, F; Gonzalez romero, E M; Colonna, N; Negret, A L; Chiaveri, E; Milazzo, P M; De almeida carrapico, C A; Castelluccio, D M

The neutron time-of-flight facility n_TOF at CERN, Switzerland, operational since 2001, delivers neutrons using the Proton Synchrotron (PS) 20 GeV/c proton beam impinging on a lead spallation target. The facility combines a very high instantaneous neutron flux, an excellent time of flight resolution due to the distance between the experimental area and the production target (185 meters), a low intrinsic background and a wide range of neutron energies, from thermal to GeV neutrons. These characteristics provide a unique possibility to perform neutron-induced capture and fission cross-section measurements for applications in nuclear astrophysics and in nuclear reactor technology.

Doppler time-of-flight imaging

KAUST Repository

Heidrich, Wolfgang

2017-02-16

Systems and methods for imaging object velocity are provided. In an embodiment, at least one Time-of-Flight camera is used to capture a signal representative of an object in motion over an exposure time. Illumination and modulation frequency of the captured motion are coded within the exposure time. A change of illumination frequency is mapped to measured pixel intensities of the captured motion within the exposure time, and information about a Doppler shift in the illumination frequency is extracted to obtain a measurement of instantaneous per pixel velocity of the object in motion. The radial velocity information of the object in motion can be simultaneously captured for each pixel captured within the exposure time. In one or more aspects, the illumination frequency can be coded orthogonal to the modulation frequency of the captured motion. The change of illumination frequency can correspond to radial object velocity.

Monoacylglycerol Analysis Using MS/MSALL Quadruple Time of Flight Mass Spectrometry

Directory of Open Access Journals (Sweden)

Fei Gao

2016-08-01

Full Text Available Monoacylglycerols (MAGs are structural and bioactive metabolites critical for biological function. Development of facile tools for measuring MAG are essential to understand its role in different diseases and various pathways. A data-independent acquisition method, MS/MSALL, using electrospray ionization (ESI coupled quadrupole time of flight mass spectrometry (MS, was utilized for the structural identification and quantitative analysis of individual MAG molecular species. Compared with other acylglycerols, diacylglycerols (DAG and triacylglycerols (TAG, MAG characteristically presented as a dominant protonated ion, [M + H]+, and under low collision energy as fatty acid-like fragments due to the neutral loss of the glycerol head group. At low concentrations (<10 pmol/µL, where lipid-lipid interactions are rare, there was a strong linear correlation between ion abundance and MAG concentration. Moreover, using the MS/MSALL method the major MAG species from human plasma and mouse brown and white adipose tissues were quantified in less than 6 min. Collectively, these results demonstrate that MS/MSALL analysis of MAG is an enabling strategy for the direct identification and quantitative analysis of low level MAG species from biological samples with high throughput and sensitivity.

Fluence measurement at the neutron time of flight experiment at CERN

CERN Document Server

Weiss, Christina; Jericha, Erwin

At the neutron time of flight facility n_TOF at CERN a new spallation target was installed in 2008. In 2008 and 2009 the commissioning of the new target took place. During the summer 2009 a fission chamber of the Physikalisch Technische Bundesanstalt (PTB) Braunschweig was used for the neutron fluence measurement. The evaluation of the data recorded with this detector is the primary topic of this thesis. Additionally a neutron transmission experiment with air has been performed at the TRIGA Mark II reactor of the Atomic Institute of the Austrian Universities (ATI). The experiment was implemented to clarify a question about the scattering cross section of molecular gas which could not be answered clearly via the literature. This problem came up during the evaluations for n_TOF.

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.

Gas-phase pesticide measurement using iodide ionization time-of-flight mass spectrometry

Directory of Open Access Journals (Sweden)

T. Murschell

2017-06-01

Full Text Available Volatilization and subsequent processing in the atmosphere are an important environmental pathway for the transport and chemical fate of pesticides. However, these processes remain a particularly poorly understood component of pesticide lifecycles due to analytical challenges in measuring pesticides in the atmosphere. Most pesticide measurements require long (hours to days sampling times coupled with offline analysis, inhibiting observation of meteorologically driven events or investigation of rapid oxidation chemistry. Here, we present chemical ionization time-of-flight mass spectrometry with iodide reagent ions as a fast and sensitive measurement of four current-use pesticides. These semi-volatile pesticides were calibrated with injections of solutions onto a filter and subsequently volatilized to generate gas-phase analytes. Trifluralin and atrazine are detected as iodide–molecule adducts, while permethrin and metolachlor are detected as adducts between iodide and fragments of the parent analyte molecule. Limits of detection (1 s are 0.37, 0.67, 0.56, and 1.1 µg m−3 for gas-phase trifluralin, metolachlor, atrazine, and permethrin, respectively. The sensitivities of trifluralin and metolachlor depend on relative humidity, changing as much as 70 and 59, respectively, as relative humidity of the sample air varies from 0 to 80 %. This measurement approach is thus appropriate for laboratory experiments and potentially near-source field measurements.

Mass cytometry: technique for real time single cell multitarget immunoassay based on inductively coupled plasma time-of-flight mass spectrometry.

Science.gov (United States)

Bandura, Dmitry R; Baranov, Vladimir I; Ornatsky, Olga I; Antonov, Alexei; Kinach, Robert; Lou, Xudong; Pavlov, Serguei; Vorobiev, Sergey; Dick, John E; Tanner, Scott D

2009-08-15

A novel instrument for real time analysis of individual biological cells or other microparticles is described. The instrument is based on inductively coupled plasma time-of-flight mass spectrometry and comprises a three-aperture plasma-vacuum interface, a dc quadrupole turning optics for decoupling ions from neutral components, an rf quadrupole ion guide discriminating against low-mass dominant plasma ions, a point-to-parallel focusing dc quadrupole doublet, an orthogonal acceleration reflectron analyzer, a discrete dynode fast ion detector, and an 8-bit 1 GHz digitizer. A high spectrum generation frequency of 76.8 kHz provides capability for collecting multiple spectra from each particle-induced transient ion cloud, typically of 200-300 micros duration. It is shown that the transients can be resolved and characterized individually at a peak frequency of 1100 particles per second. Design considerations and optimization data are presented. The figures of merit of the instrument are measured under standard inductively coupled plasma (ICP) operating conditions ( 900 for m/z = 159, the sensitivity with a standard sample introduction system of >1.4 x 10(8) ion counts per second per mg L(-1) of Tb and an abundance sensitivity of (6 x 10(-4))-(1.4 x 10(-3)) (trailing and leading masses, respectively) are shown. The mass range (m/z = 125-215) and abundance sensitivity are sufficient for elemental immunoassay with up to 60 distinct available elemental tags. When 500) can be used, which provides >2.4 x 10(8) cps per mg L(-1) of Tb, at (1.5 x 10(-3))-(5.0 x 10(-3)) abundance sensitivity. The real-time simultaneous detection of multiple isotopes from individual 1.8 microm polystyrene beads labeled with lanthanides is shown. A real time single cell 20 antigen expression assay of model cell lines and leukemia patient samples immuno-labeled with lanthanide-tagged antibodies is presented.

Comparison of detector materials for time-of-flight positron tomography

International Nuclear Information System (INIS)

Derenzo, S.E.

1982-06-01

Knowledge of detection efficiency and timing resolution is essential when comparing detector materials for time-of-flight positron tomography. We present results of Monte Carlo calculations of the detection efficiency of plastic, lead loaded plastic, NaI(T1), liquid xenon, bismuth germanate (BGO), CsF, BaF 2 , Ge, and HgI 2 for 511 keV photons. We also use recently published values of timing resolution for these detector materials to tabulate the quantity (efficiency) 2 /(time resolution) which is a measure of the relative sensitivity for time of flight positron tomography

Thin Time-Of-Flight PET project

CERN Multimedia

The pre-R&D aims at designing and producing a compact and thin Time-Of-Flight PET detector device with depth of interaction measurement capability, which employs layered silicon sensors as active material, with a readout consisting of a new generation of very-low noise and very fast electronics based on SiGe Heterojunction Bipolar Transistors (HBT) components.

A paper based inkjet printed real time location tracking TAG

KAUST Repository

Farooqui, Muhammad Fahad

2013-06-01

This paper presents, for the first time, an inkjet printed, wearable, low-cost, light weight and miniaturized real time locating TAG on an ordinary photo-paper. The 29 grams, 9 cm×8 cm×0.5 cm TAG integrates a GPS/GSM module, a microcontroller with on-paper GPS and GSM antennas. A novel monopole antenna with an L shaped slit is introduced to achieve the required circular polarization for the GPS band. Issues related to integration of active components (e.g. BGA chip) on inkjet-printed paper substrates are discussed. The system enables location tracking through a user-friendly interface accessible through all internet enabled devices. Field tests show an update interval of 15 sec, stationary position error of 6.2m and real time tracking error of 4.7m which is 4 times better than the state-of-the-art. Due to the flexible nature of the paper substrate, the TAG can be designed for different shapes such as a wrist band for child tracking or a collar band for pet tracking applications. © 2013 IEEE.

A Measurement of $R_{b}$ using a Double Tagging Method

CERN Document Server

Abbiendi, G.; Alexander, G.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Bartoldus, R.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bird, S.D.; Blobel, V.; Bloodworth, I.J.; Bobinski, M.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Burgard, C.; Burgin, R.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Davis, R.; De Jong, S.; del Pozo, L.A.; De Roeck, A.; Desch, K.; Dienes, B.; Dixit, M.S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Eatough, D.; Estabrooks, P.G.; Etzion, E.; Evans, H.G.; Fabbri, F.; Fanti, M.; Faust, A.A.; Fiedler, F.; Fierro, M.; Fleck, I.; Folman, R.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gascon-Shotkin, S.M.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Hargrove, C.K.; Hartmann, C.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herndon, M.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hillier, S.J.; Hobson, P.R.; Hocker, James Andrew; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D.S.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G.D.; Lanske, D.; Lauber, J.; Lautenschlager, S.R.; Lawson, I.; Layter, J.G.; Lazic, D.; Lee, A.M.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Ludwig, J.; Lui, D.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Markopoulos, C.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menke, S.; Merritt, F.S.; Mes, H.; Meyer, J.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nellen, B.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oreglia, M.J.; Orito, S.; Palinkas, J.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Polok, J.; Przybycien, M.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schieck, J.; Schmitt, B.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Tanaka, S.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomson, M.A.; von Torne, E.; Torrence, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turcot, A.S.; Turner-Watson, M.F.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

1999-01-01

The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model.

Time-of-Flight Measurements as a Possible Method to Observe Anyonic Statistics

Science.gov (United States)

Umucalılar, R. O.; Macaluso, E.; Comparin, T.; Carusotto, I.

2018-06-01

We propose a standard time-of-flight experiment as a method for observing the anyonic statistics of quasiholes in a fractional quantum Hall state of ultracold atoms. The quasihole states can be stably prepared by pinning the quasiholes with localized potentials and a measurement of the mean square radius of the freely expanding cloud, which is related to the average total angular momentum of the initial state, offers direct signatures of the statistical phase. Our proposed method is validated by Monte Carlo calculations for ν =1 /2 and 1 /3 fractional quantum Hall liquids containing a realistic number of particles. Extensions to quantum Hall liquids of light and to non-Abelian anyons are briefly discussed.

A high-resolution, multi-stop, time-to-digital converter for nuclear time-of-flight measurements

International Nuclear Information System (INIS)

Spencer, D.F.; Cole, J.; Drigert, M.; Aryaeinejad, R.

2006-01-01

A high-resolution, multi-stop, time-to-digital converter (TDC) was designed and developed to precisely measure the times-of-flight (TOF) of incident neutrons responsible for induced fission and capture reactions on actinide targets. The minimum time resolution is ±1 ns. The TDC design was implemented into a single, dual-wide CAMAC module. The CAMAC bus is used for command and control as well as an alternative data output. A high-speed ECL interface, compatible with LeCroy FERA modules, was also provided for the principle data output path. An Actel high-speed field programmable gate array (FPGA) chip was incorporated with an external oscillator and an internal multiple clock phasing system. This device implemented the majority of the high-speed register functions, the state machine for the FERA interface, and the high-speed counting circuit used for the TDC conversion. An external microcontroller was used to monitor and control system-level changes. In this work we discuss the performance of this TDC module as well as its application

The ALICE Time of Flight Readout System AFRO

CERN Document Server

Kluge, A

1999-01-01

The ALICE Time of Flight Detector system comprises more than 100.000 channels and covers an area of more than 100 m2. The timing resolution should be better than 150 ps. This combination of requirements poses a major challenge to the readout system. All detector timing measurements are referenced to a unique start signal t0. This signal is generated at the time an event occurs. Timing measurements are performed using a multichannel TDC chip which requires a 40 MHz reference clock signal. The general concept of the readout system is based on a modular architecture. Detector cells are combined to modules of 1024 channels. Each of these modules can be read out and calibrated independently from each other. By distributing a reference signal, a timing relationship between the modules is established. This reference signal can either be the start signal t0 or the TDC-reference clock. The readout architecture is divided into three steps; the TDC controller, the module controller, and the time of flight controller. Th...

Pulsed time-of-flight refractometry measurements of the electron density in the T-11M tokamak

International Nuclear Information System (INIS)

Petrov, A.A.; Petrov, V.G.; Malyshev, A.Yu.; Markov, V.K.; Babarykin, A.V.

2002-01-01

A new method for measuring the plasma density in magnetic confinement systems - pulsed time-of-flight refractometry - is developed and tested experimentally in the T-11M tokamak. The method is based on the measurements of the time delay of short (with a duration of several nanoseconds) microwave pulses propagating through the plasma. When the probing frequency is much higher than the plasma frequency, the measured delay in the propagation time is proportional to the line-averaged electron density regardless of the density profile. A key problem in such measurements is the short time delay of the pulse in the plasma (∼1 ns or less for small devices) and, consequently, low accuracy of the measurements of the average density. Various methods for improving the accuracy of such measurements are proposed and implemented in the T-11M experiments. The measurements of the line-averaged density in the T-11M tokamak in the low-density plasma regime are performed. The results obtained agree satisfactorily with interferometric data. The measurement errors are analyzed, and the possibility of using this technique to measure the electron density profile and the position of the plasma column is discussed

A high performance Time-of-Flight detector applied to isochronous mass measurement at CSRe

International Nuclear Information System (INIS)

Mei Bo; Tu Xiaolin; Wang Meng; Xu Hushan; Mao Ruishi; Hu Zhengguo; Ma Xinwen; Yuan Youjin; Zhang Xueying; Geng Peng; Shuai Peng; Zang Yongdong; Tang Shuwen; Ma Peng; Lu Wan; Yan Xinshuai; Xia Jiawen; Xiao Guoqing; Guo Zhongyan; Zhang Hongbin

2010-01-01

A high performance Time-of-Flight detector has been designed and constructed for isochronous mass spectrometry at the experimental Cooler Storage Ring (CSRe). The detector has been successfully used in an experiment to measure the masses of the N∼Z∼33 nuclides near the proton drip-line. Of particular interest is the mass of 65 As. A maximum detection efficiency of 70% and a time resolution of 118±8 ps (FWHM) have been achieved in the experiment. The dependence of detection efficiency and signal average pulse height (APH) on atomic number Z has been studied. The potential of APH for Z identification has been discussed.

Fingerprinting of egg and oil binders in painted artworks by matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of lipid oxidation by-products.

Science.gov (United States)

Calvano, C D; van der Werf, I D; Palmisano, F; Sabbatini, L

2011-06-01

A matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based approach was applied for the detection of various lipid classes, such as triacylglycerols (TAGs) and phospholipids (PLs), and their oxidation by-products in extracts of small (50-100 μg) samples obtained from painted artworks. Ageing of test specimens under various conditions, including the presence of different pigments, was preliminarily investigated. During ageing, the TAGs and PLs content decreased, whereas the amount of diglycerides, short-chain oxidative products arising from TAGs and PLs, and oxidized TAGs and PLs components increased. The examination of a series of model paint samples gave a clear indication that specific ions produced by oxidative cleavage of PLs and/or TAGs may be used as markers for egg and drying oil-based binders. Their elemental composition and hypothetical structure are also tentatively proposed. Moreover, the simultaneous presence of egg and oil binders can be easily and unambiguously ascertained through the simultaneous occurrence of the relevant specific markers. The potential of the proposed approach was demonstrated for the first time by the analysis of real samples from a polyptych of Bartolomeo Vivarini (fifteenth century) and a "French school" canvas painting (seventeenth century).

Molecular beam studies with a time-of-flight machine

International Nuclear Information System (INIS)

Beijerinck, H.C.W.

1975-01-01

The study concerns the development of the time-of-flight method for the velocity analysis of molecular beams and its application to the measurement of the velocity dependence of the total cross-section of the noble gases. It reviews the elastic scattering theory, both in the framework of classical mechanics and in the quantum mechanical description. Attention is paid to the semiclassical correspondence of classical particle trajectories with the partial waves of the quantum mechanical solution. The total cross-section and the small angle differential cross-section are discussed with special emphasis on their relation. The results of this chapter are used later to derive the correction on the measured total cross-section due to the finite angular resolution of the apparatus. Reviewed also is the available information on the intermolecular potential of the Ar-Ar system. Then a discussion of the measurement of total cross-sections with the molecular beam method and the time-of-flight method is compared to other methods used. It is shown that the single burst time-of-flight method can be developed into a reliable and well-calibrated method for the analysis of the velocity distribution of molecular beams. A comparison of the single burst time-of-flight method with the cross-correlation time-of-flight method shows that the two methods are complementary and that the specific experimental circumstances determine which method is to be preferred. Molecular beam sources are discussed. The peaking factor formalism is introduced and helps to compare the performance of different types of sources. The effusive and the supersonic source are treated and recent experimental results are given. The multichannel source is treated in more detail. For the opaque mode, an experimental investigation of the velocity distribution and the angular distribution of the flow pattern is presented. Comparison of these results with Monte Carlo calculations for free molecular flow in a cylindrical

Advanced in-flight measurement techniques

CERN Document Server

Lawson, Nicholas; Jentink, Henk; Kompenhans, Jürgen

2013-01-01

The book presents a synopsis of the main results achieved during the 3 year EU-project "Advanced Inflight Measurement Techniques (AIM)" which applied advanced image based measurement techniques to industrial flight testing. The book is intended to be not only an overview on the AIM activities but also a guide on the application of advanced optical measurement techniques for future flight testing. Furthermore it is a useful guide for engineers in the field of experimental methods and flight testing who face the challenge of a future requirement for the development of highly accurate non-intrusive in-flight measurement techniques.

Multichannel analyzer for the neutron time-of-flight spectrometer

International Nuclear Information System (INIS)

Vojter, A.P.; Slyisenko, V.Yi.; Doronyin, M.Yi.; Maznij, Yi.O.; Vasil'kevich, O.A.; Golyik, V.V.; Koval'ov, O.M.; Kopachov, V.Yi.; Savchuk, V.G.

2010-01-01

New multichannel time-of-flight spectrometer for the measurement of the energy and angular distributions of neutrons from the WWWR-M reactor is considered. This spectrometer has been developed for the replacement of the previous one to increase the number of channels and measurement precision, reduce the time of channel tuning and provide the automatic monitoring during the experiment.

Time-of-flight Measurement Of Hole-tunneling Properties And Emission Color Control In Organic Light-emitting Diodes

Science.gov (United States)

Kurata, K.; Kashiwabara, K.; Nakajima, K.; Mizoguchi, Y.; Ohtani, N.

2011-12-01

Hole transport properties of organic light-emitting diodes (OLEDs) with a thin hole-blocking layer (HBL) were evaluated by time-of-flight measurement. Electroluminescence (EL) spectra of OLEDs with various HBL thicknesses were also evaluated. The results clearly show that the time-resolved photocurrent response and the emission color strongly depend on HBL thickness. This can be attributed to hole-tunneling through the thin HBL. We successfully fabricated a white OLED by controlling the thickness of HBL.

Measurement of residual strain in composites by means of time-of- flight neutron diffraction

International Nuclear Information System (INIS)

Kupperman, D.S.; Majumdar, S.; Richardson, J.; Saigal, A.

1993-01-01

Neutron diffraction time-of-flight measurements using the Intense Pulsed Neutron Source at Argonne National Laboratory have been employed to study strain in various metal- and ceramic-matrix composites. For example, measurements carried out to 900 C on a composite composed of a titanium alloy matrix and silicon carbide fibers have been used to validate theoretical assumptions in the prediction of fabrication-induced residual stress. Sapphire reinforced nickel aluminide composites have also been studied. Studies of a high-temperature ceramic superconducting composite consisting of yttrium barium copper oxide and silver with various volume fractions of silver have also been carried out. The results of these studies have provided information on the effect of Ag content on interface bonding. In addition, ceramic-matrix composites with randomly dispersed ceramic whiskers with varying fiber content have been investigated

A Time-of-Flight System for Low Energy Charged Particles

Science.gov (United States)

Giordano, Micheal; Sadwick, Krystalyn; Fletcher, Kurt; Padalino, Stephen

2013-10-01

A time-of-flight system has been developed to measure the energy of charged particles in the keV range. Positively charged ions passing through very thin carbon films mounted on grids generate secondary electrons. These electrons are accelerated by a -2000 V grid bias towards a grounded channeltron electron multiplier (CEM) which amplifies the signal. Two CEM detector assemblies are mounted 23.1 cm apart along the path of the ions. An ion generates a start signal by passing through the first CEM and a stop signal by passing through the second. The start and stop signals generate a time-of-flight spectrum via conventional electronics. Higher energy alpha particles from radioactive sources have been used to test the system. This time-of-flight system will be deployed to measure the energies of 15 to 30 keV ions produced by a duoplasmatron ion source that is used to characterize ICF detectors.

Energy measurement using a resonator-based time-of-flight system

International Nuclear Information System (INIS)

Pardo, R.C.; Lewis, R.N.; Johnson, K.W.; Clifft, B.

1983-01-01

The resonant time-of-flight system which has been developed has several advantages over other potential approaches. The system is non-interceptive and nondestructive. The beam phase space is preserved. It is non-dispersive. Path length variations are not introduced into the beam transport which would reduce the timing resolution. It has a large signal-to-noise ratio when compared to non-resonant beam pick-up techniques. It provides the means to precisely set the linac energy and, potentially, to control the energy in a feedback loop is desired. It is less expensive than an equivalent magnetic system

Comparative Performance of Acoustic-tagged and PIT-tagged Juvenile Salmonids

Energy Technology Data Exchange (ETDEWEB)

Hockersmith, Eric E.; Brown, Richard S.; Liedtke, Theresa L.

2008-02-01

Numerous research tools and technologies are currently being used to evaluate fish passage and survival to determine the impacts of the Federal Columbia River Power System (FCRPS) on endangered and threatened juvenile salmonids, including PIT tags, balloon tags, hydroacoustic evaluations, radio telemetry, and acoustic telemetry. Each has advantages and disadvantages, but options are restricted in some situations because of limited capabilities of a specific technology, lack of detection capability downstream, or availability of adequate numbers of fish. However, there remains concern about the comparative effects of the tag or the tagging procedure on fish performance. The recently developed Juvenile Salmonid Acoustic Telemetry System (JSATS) acoustic transmitter is the smallest active acoustic tag currently available. The goal of this study was to determine whether fish tagged with the JSATS acoustic-telemetry tag can provide unbiased estimates of passage behavior and survival within the performance life of the tag. We conducted both field and laboratory studies to assess tag effects. For the field evaluation we released a total of 996 acoustic-tagged fish in conjunction with 21,026 PIT-tagged fish into the tailrace of Lower Granite Dam on 6 and 13 May. Travel times between release and downstream dams were not significantly different for the majority of the reaches between acoustic-tagged and PIT-tagged fish. In addition to the field evaluation, a series of laboratory experiments were conducted to determine if growth and survival of juvenile Chinook salmon surgically implanted with acoustic transmitters is different than untagged or PIT tagged juvenile Chinook salmon. Only yearling fish with integrated and non-integrated transmitters experienced mortalities, and these were low (<4.5%). Mortality among sub-yearling control and PIT-tag treatments ranged up to 7.7% while integrated and non-integrated treatments had slightly higher rates (up to 8.3% and 7

SHMS Hodoscopes and Time of Flight System

Science.gov (United States)

Craycraft, Kayla; Malace, Simona

2017-09-01

As part of the Thomas Jefferson National Accelerator Facility's (Jefferson Lab) upgrade from 6 GeV to 12 GeV, a new magnetic focusing spectrometer, the Super High Momentum Spectrometer (SHMS), was installed in experimental Hall C. The detector stack consists of horizontal drift chambers for tracking, gas Cerenkov and Aerogel detectors and a lead glass calorimeter for particle identification. A hodoscope system consisting of three planes of scintillator detectors (constructed by James Madison University) and one plane of quartz bars (built by North Carolina A&T State University) is used for triggering and time of flight measurements. This presentation consists of discussion of the installation, calibration, and characterization of the detectors used in this Time of Flight system. James Madison University, North Carolina A&T State University.

Sample-interpolation timing: an optimized technique for the digital measurement of time of flight for γ rays and neutrons at relatively low sampling rates

International Nuclear Information System (INIS)

Aspinall, M D; Joyce, M J; Mackin, R O; Jarrah, Z; Boston, A J; Nolan, P J; Peyton, A J; Hawkes, N P

2009-01-01

A unique, digital time pick-off method, known as sample-interpolation timing (SIT) is described. This method demonstrates the possibility of improved timing resolution for the digital measurement of time of flight compared with digital replica-analogue time pick-off methods for signals sampled at relatively low rates. Three analogue timing methods have been replicated in the digital domain (leading-edge, crossover and constant-fraction timing) for pulse data sampled at 8 GSa s −1 . Events arising from the 7 Li(p, n) 7 Be reaction have been detected with an EJ-301 organic liquid scintillator and recorded with a fast digital sampling oscilloscope. Sample-interpolation timing was developed solely for the digital domain and thus performs more efficiently on digital signals compared with analogue time pick-off methods replicated digitally, especially for fast signals that are sampled at rates that current affordable and portable devices can achieve. Sample interpolation can be applied to any analogue timing method replicated digitally and thus also has the potential to exploit the generic capabilities of analogue techniques with the benefits of operating in the digital domain. A threshold in sampling rate with respect to the signal pulse width is observed beyond which further improvements in timing resolution are not attained. This advance is relevant to many applications in which time-of-flight measurement is essential

Calibration and adjustment of the EGRET coincidence/time-of-flight system

International Nuclear Information System (INIS)

Hunter, S.D.

1991-01-01

The coincidence/time-of-flight system of the energetic gamma ray experiment telescope (EGRET) on NASA's Gamma Ray Observatory (GRO) consists of two layers of sixteen scintillator tiles. These tiles are paired into 96 coincidence telescopes. Valid coincidence and time-of-flight values (indicating downward moving particles) from one of these telescopes are two of the requirements for an EGRET event trigger. To maximize up-down discrimination, variations in the mean timing value of the telescopes must be minimized. The timing values of the 96 telescopes are not independent, hence they cannot be individually adjusted to calibrate the system. An iterative approach was devised to determine adjustments to the length of the photomultiplier signal cables. These adjustments were made directly in units of time using a time domain reflectometry technique, by timing the reflection of a fast pulse from the unterminated end of eable, and observing the charge in signal propagation time as the length of the cable was shortened. Two constant fraction discriminators, a time-to-amplitude converter and a pulse height analyzer were used for these measurements. Using this direct time measuring approach, the timing values for the 96 EGRET coincidence/time-of-flight telescopes were adjusted with an FWHM variation of less than 450 ps (± 1 TOF timing channel). (orig.)

Development of Hydroxyl Tagging Velocimetry for Low Velocity Flows

Science.gov (United States)

Andre, Matthieu A.; Bardet, Philippe M.; Burns, Ross A.; Danehy, Paul M.

2016-01-01

Hydroxyl tagging velocimetry (HTV) is a molecular tagging technique that relies on the photo-dissociation of water vapor into OH radicals and their subsequent tracking using laser induced fluorescence. Velocities are then obtained from time-of-flight calculations. At ambient temperature in air, the OH species lifetime is relatively short (<50 µs), making it suited for high speed flows. Lifetime and radicals formation increases with temperature, which allows HTV to also probe low-velocity, high-temperature flows or reacting flows such as flames. The present work aims at extending the domain of applicability of HTV, particularly towards low-speed (<10 m/s) and moderate (<500 K) temperature flows. Results are compared to particle image velocimetry (PIV) measurements recorded in identical conditions. Single shot and averaged velocity profiles are obtained in an air jet at room temperature. By modestly raising the temperature (100-200 degC) the OH production increases, resulting in an improvement of the signal-to-noise ratio (SNR). Use of nitrogen - a non-reactive gas with minimal collisional quenching - extends the OH species lifetime (to over 500 µs), which allows probing of slower flows or, alternately, increases the measurement precision at the expense of spatial resolution. Instantaneous velocity profiles are resolved in a 100degC nitrogen jet (maximum jet-center velocity of 6.5 m/s) with an uncertainty down to 0.10 m/s (1.5%) at 68% confidence level. MTV measurements are compared with particle image velocimetry and show agreement within 2%.

Billfish Tagging

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The SWFSC's constituent-based Billfish Tagging Program began in 1963 and since that time has provided conventional spaghetti type tags and tagging supplies to...

UTOFIA: an underwater time-of-flight image acquisition system

Science.gov (United States)

Driewer, Adrian; Abrosimov, Igor; Alexander, Jonathan; Benger, Marc; O'Farrell, Marion; Haugholt, Karl Henrik; Softley, Chris; Thielemann, Jens T.; Thorstensen, Jostein; Yates, Chris

2017-10-01

In this article the development of a newly designed Time-of-Flight (ToF) image sensor for underwater applications is described. The sensor is developed as part of the project UTOFIA (underwater time-of-flight image acquisition) funded by the EU within the Horizon 2020 framework. This project aims to develop a camera based on range gating that extends the visible range compared to conventional cameras by a factor of 2 to 3 and delivers real-time range information by means of a 3D video stream. The principle of underwater range gating as well as the concept of the image sensor are presented. Based on measurements on a test image sensor a pixel structure that suits best to the requirements has been selected. Within an extensive characterization underwater the capability of distance measurements in turbid environments is demonstrated.

Measurement of the b-jet tagging efficiency using top quark pair events with ATLAS data

CERN Document Server

Leyko, A; The ATLAS collaboration

2012-01-01

Many physics analyses with the ATLAS data at the LHC expect to have jets originating from b-quarks in the final state. Algorithms that allow to identify such jets are thus of great importance and it is crucial to study their performance directly in data by measuring the tagging efficiencies and fake rates. Since the top quark almost exclusively decays to a W boson and a b-quark, a sample of top quark pair events (tt ̄) is ideal for studying the b-tagging performance. Final states containing one or two leptons have been used to measure the b-tagging efficiency, either by count- ing the number of b-tagged jets, by exploiting the kinematics of top quark pair decays and flavour composition of studied sample or by applying a kinematic fit to extract a sample rich in b-jets. The calibration methods based on top quark pair events are especially important because they can provide measurements of the b-tagging efficiency also for jets with high transverse momentum. Three different methods using two statistically inde...

Real-time flavor tagging selection in ATLAS

CERN Document Server

Madaffari, D

2016-01-01

In high-energy physics experiments the online selection is crucial to reject the overwhelming uninteresting collisions. In particular the ATLAS experiment includes b-jet selections in its trigger, in order to select final states with significant heavy-flavor content. Dedicated selections are developed to timely identifying fully hadronic final states containing b-jets and maintaining affordable trigger rates. ATLAS successfully operated b-jet trigger selections during both 2011 and 2012 Large Hadron Collider data-taking campaigns. Work is on-going now to improve the performance of online tagging algorithms to be deployed in Run 2 in 2015. An overview of the Run 1 ATLAS b-jet trigger strategy along with future prospects is presented in this paper. Data-driven techniques to extract the online b-tagging performance, a key ingredient for all analysis relying on such triggers, are also discussed and preliminary results presented.

A PCI time digitizer for the new JET time-of-flight neutron spectrometer

International Nuclear Information System (INIS)

Sousa, J.; Batista, A.J.N.; Combo, A.; Pereira, R.; Cruz, N.; Carvalho, P.; Varandas, C.A.F.; Conroy, S.; Ericsson, G.; Kaellne, J.

2004-01-01

A PCI time digitizer module with eight independent time-to-digital converter (TDC) channels is being developed for the new time-of-flight spectrometer designed for optimized rate (TOFOR) which diagnoses deuterium plasmas of the EFDA-JET tokamak. The module shall measure with high accuracy the flight-times of 2.5 MeV neutrons in the 100 ns range as given by two groups of scintillation detectors operating at average event rates from the expected 500 kHz up to 5 MHz. The module stores up to 64 million hit-times with a resolution of 0.4 ns and incorporates a digital signal processor and a system-on-chip device which performs the data transfer, the device control/monitoring and may perform statistical, data reduction or control algorithms in real-time

Timing performances of a data acquisition system for Time of Flight PET

International Nuclear Information System (INIS)

Morrocchi, Matteo; Marcatili, Sara; Belcari, Nicola; Bisogni, Maria G.; Collazuol, Gianmaria; Ambrosi, Giovanni; Corsi, Francesco; Foresta, Maurizio; Marzocca, Cristoforo; Matarrese, Gianvito; Sportelli, Giancarlo; Guerra, Pedro; Santos, Andres; Del Guerra, Alberto

2012-01-01

We are investigating the performances of a data acquisition system for Time of Flight PET, based on LYSO crystal slabs and 64 channels Silicon Photomultipliers matrices (1.2 cm 2 of active area each). Measurements have been performed to test the timing capability of the detection system (SiPM matices coupled to a LYSO slab and the read-out electronics) with both test signal and radioactive source.

Four-Spot Time-Of-Flight Laser Anemometer For Turbomachinery

Science.gov (United States)

Wernet, Mark P.; Skoch, Gary J.

1995-01-01

Two-color, four-spot time-of-flight laser anemometer designed for measuring flow velocity within narrow confines of small centrifugal compressor. Apparatus well suited for measuring fast (typical speeds 160 to 700 m/s), highly turbulent gas flows in turbomachinery. Other potential applications include measurement of gas flows in pipelines and in flows from explosions.

Cosmic radiation algorithm utilizing flight time tables

International Nuclear Information System (INIS)

Katja Kojo, M.Sc.; Mika Helminen, M.Sc.; Anssi Auvinen, M.D.Ph.D.; Katja Kojo, M.Sc.; Anssi Auvinen, M.D.Ph.D.; Gerhard Leuthold, D.Sc.

2006-01-01

Cosmic radiation is considerably higher on cruising altitudes used in aviation than at ground level. Exposure to cosmic radiation may increase cancer risk among pilots and cabin crew. The International Commission on Radiation Protection (ICRP) has recommended that air crew should be classified as radiation workers. Quantification of cosmic radiation doses is necessary for assessment of potential health effects of such occupational exposure. For Finnair cabin crew (cabin attendants and stewards), flight history is not available for years prior to 1991 and therefore, other sources of information on number and type of flights have to be used. The lack of systematically recorded information is a problem for dose estimation for many other flight companies personnel as well. Several cosmic radiation dose estimations for cabin crew have been performed using different methods (e.g. 2-5), but they have suffered from various shortcomings. Retrospective exposure estimation is not possible with personal portable dosimeters. Methods that employ survey data for occupational dose assessment are prone to non-differential measurement error i.e. the cabin attendants do not remember correctly the number of past flights. Assessment procedures that utilize surrogate measurement methods i.e. the duration of employment, lack precision. The aim of the present study was to develop an assessment method for individual occupational exposure to cosmic radiation based on flight time tables. Our method provides an assessment method that does not require survey data or systematic recording of flight history, and it is rather quick, inexpensive, and possible to carry out in all other flight companies whose past time tables for the past periods exist. Dose assessment methods that employ survey data are prone to random error i.e. the cabin attendants do not remember correctly the number or types of routes that they have flown during the past. Our method avoids this since survey data are not needed

Time-of-flight spectrometers

International Nuclear Information System (INIS)

Carrico, J.P.

1976-01-01

The flight time of an ion in an inhomogeneous, oscillatory electric field (IOFE) is an m/e-dependent property of this field and is independent of the initial position and velocity. The d.c. component of the equation of motion for an ion in the IOFE describes a harmonic oscillation of constant period. When ions oscillate for many periods with one species overtaking another the motion may no longer be truly periodic although the resulting period or 'quasi-period' still remains independent of the initial conditions. This period or 'quasi-period' is used in the time-of-flight mass spectrometer described. The principle of operation is also described and both analytical and experimental results are reported. (B.D.)

Principles of time-of-flight tomography

International Nuclear Information System (INIS)

Campagnolo, R.; Garderet, P.; Lecomte, J.L.; Bouvier, A.; Darier, P.; Soussaline, F.

1983-03-01

After a short introduction to the physics of time-of-flight positron tomography, the various aspects of this technique are presented. The characteristics including data acquisition and image reconstruction system of a positron tomograph (TTV01) which uses time-of-flight information, are described. The preliminary results obtained with TTV01, such as resolution and sensitivity, as well as phantom images, are presented [fr

Timing performances of a data acquisition system for Time of Flight PET

Energy Technology Data Exchange (ETDEWEB)

Morrocchi, Matteo, E-mail: matteo.morrocchi@pi.infn.it [University of Pisa and INFN Sezione di Pisa, I 56127 Pisa (Italy); Marcatili, Sara; Belcari, Nicola; Bisogni, Maria G. [University of Pisa and INFN Sezione di Pisa, I 56127 Pisa (Italy); Collazuol, Gianmaria [University of Padova and INFN Sezione di Padova (Italy); Ambrosi, Giovanni [INFN Sezione di Perugia, I 06100 Perugia (Italy); Corsi, Francesco; Foresta, Maurizio; Marzocca, Cristoforo; Matarrese, Gianvito [Politecnico di Bari and INFN Sezione di Bari, I 70100 Bari (Italy); Sportelli, Giancarlo; Guerra, Pedro; Santos, Andres [Universidad Politecnica de Madrid, E 28040 Madrid (Spain); Centro de Investigacion Biomedica en Red en Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN) (Spain); Del Guerra, Alberto [University of Pisa and INFN Sezione di Pisa, I 56127 Pisa (Italy)

2012-12-11

We are investigating the performances of a data acquisition system for Time of Flight PET, based on LYSO crystal slabs and 64 channels Silicon Photomultipliers matrices (1.2 cm{sup 2} of active area each). Measurements have been performed to test the timing capability of the detection system (SiPM matices coupled to a LYSO slab and the read-out electronics) with both test signal and radioactive source.

Environmental Effects on Measurement Uncertainties of Time-of-Flight Cameras

DEFF Research Database (Denmark)

Gudmundsson, Sigurjon Arni; Aanæs, Henrik; Larsen, Rasmus

2007-01-01

In this paper the effect the environment has on the SwissRanger SR3000 Time-Of-Flight camera is investigated. The accuracy of this camera is highly affected by the scene it is pointed at: Such as the reflective properties, color and gloss. Also the complexity of the scene has considerable effects...... on the accuracy. To mention a few: The angle of the objects to the emitted light and the scattering effects of near objects. In this paper a general overview of known such inaccuracy factors are described, followed by experiments illustrating the additional uncertainty factors. Specifically we give a better...

Multivariate Sensitivity Analysis of Time-of-Flight Sensor Fusion

Science.gov (United States)

Schwarz, Sebastian; Sjöström, Mårten; Olsson, Roger

2014-09-01

Obtaining three-dimensional scenery data is an essential task in computer vision, with diverse applications in various areas such as manufacturing and quality control, security and surveillance, or user interaction and entertainment. Dedicated Time-of-Flight sensors can provide detailed scenery depth in real-time and overcome short-comings of traditional stereo analysis. Nonetheless, they do not provide texture information and have limited spatial resolution. Therefore such sensors are typically combined with high resolution video sensors. Time-of-Flight Sensor Fusion is a highly active field of research. Over the recent years, there have been multiple proposals addressing important topics such as texture-guided depth upsampling and depth data denoising. In this article we take a step back and look at the underlying principles of ToF sensor fusion. We derive the ToF sensor fusion error model and evaluate its sensitivity to inaccuracies in camera calibration and depth measurements. In accordance with our findings, we propose certain courses of action to ensure high quality fusion results. With this multivariate sensitivity analysis of the ToF sensor fusion model, we provide an important guideline for designing, calibrating and running a sophisticated Time-of-Flight sensor fusion capture systems.

Inhomogeneous oscillatory electric field time-of-flight mass spectrometer

International Nuclear Information System (INIS)

Carrico, J.P.

1977-01-01

The mass-to-charge ratio of an ion can be determined from the measurement of its flight time in an inhomogeneous, oscillatory electric field produced by the potential distribution V(x, y, t) = Vsub(DC) + Vsub(AC) cos ωt) (αsub(x)X 2 + αsub(y)Y 2 + αsub(z)Z 2 ). The governing equation of motion is the Mathieu equation. The principle of operation of this novel mass spectrometer is described and results of computer calculations of the flight time and resolution are reported. An experimental apparatus and results and results demonstrating the feasibility of this mass spectrometer principle are described. (author)

COINTOF mass spectrometry: design of a time-of-flight analyzer and development of the analysis method

International Nuclear Information System (INIS)

Teyssier, C.

2012-01-01

DIAM (Device for the irradiation of molecular clusters) is a newly designed experimental setup to investigate processes resulting from the irradiation of molecular nano-systems by 20-150 keV protons. One of its specificities relies on the original technique of mass spectrometry named COINTOF (Correlated Ion and Neutral Time Of Flight) consisting in correlated measurements of the time of flight of charged and neutral fragments produced by the dissociation of a single molecular ion parent. A strategy of treatment and analysis of the detection signals was developed to distinguish two fragments close in time ( 3 O + and two water molecules. The distribution of the time of flight difference between the two neutral fragments is measured providing an estimate of the kinetic energy release of a few eV. In parallel, a second time-of-flight mass spectrometer was designed. It associates a linear time-of-flight and an orthogonal time-of-flight and integrates position detectors (delay line anode). Simulations demonstrate the potentials of the new analyzer. Finally, research works were led at the laboratory R.-J. A. Levesque (Universite de Montreal) on the imaging capabilities of the multi-pixel detectors of the MPX-ATLAS collaboration. (author)

Measuring time-of-flight in an ultrasonic LPS system using generalized cross-correlation.

Science.gov (United States)

Villladangos, José Manuel; Ureña, Jesús; García, Juan Jesús; Mazo, Manuel; Hernández, Alvaro; Jiménez, Ana; Ruíz, Daniel; De Marziani, Carlos

2011-01-01

In this article, a time-of-flight detection technique in the frequency domain is described for an ultrasonic local positioning system (LPS) based on encoded beacons. Beacon transmissions have been synchronized and become simultaneous by means of the DS-CDMA (direct-sequence code Division multiple access) technique. Every beacon has been associated to a 255-bit Kasami code. The detection of signal arrival instant at the receiver, from which the distance to each beacon can be obtained, is based on the application of the generalized cross-correlation (GCC), by using the cross-spectral density between the received signal and the sequence to be detected. Prior filtering to enhance the frequency components around the carrier frequency (40 kHz) has improved estimations when obtaining the correlation function maximum, which implies an improvement in distance measurement precision. Positioning has been achieved by using hyperbolic trilateration, based on the time differences of arrival (TDOA) between a reference beacon and the others.

Flight safety measurements of UAVs in congested airspace

Directory of Open Access Journals (Sweden)

Xiang Jinwu

2016-10-01

Full Text Available Describing spatial safety status is crucial for high-density air traffic involving multiple unmanned aerial vehicles (UAVs in a complex environment. A probabilistic approach is proposed to measure safety situation in congested airspace. The occupancy distribution of the airspace is represented with conflict probability between spatial positions and UAV. The concept of a safety envelope related to flight performance and response time is presented first instead of the conventional fixed-size protected zones around aircraft. Consequently, the conflict probability is performance-dependent, and effects of various UAVs on safety can be distinguished. The uncertainty of a UAV future position is explicitly accounted for as Brownian motion. An analytic approximate algorithm for the conflict probability is developed to decrease the computational consumption. The relationship between safety and flight performance are discussed for different response times and prediction intervals. To illustrate the applications of the approach, an experiment of three UAVs in formation flight is performed. In addition, an example of trajectory planning is simulated for one UAV flying over airspace where five UAVs exist. The validation of the approach shows its potential in guaranteeing flight safety in highly dynamic environment.

Time of flight diffraction technique and applications for retaining rings and turbine discs

International Nuclear Information System (INIS)

Ashwin, P.

1990-01-01

During recent times the term Time of Flight has become a popular phrase in ultrasonic terminology. It is true to say that since ultrasonic energy was first applied for NDE applications, we have used the time of flight to measure the material thickness and establish the presence of discontinuities in metals and other materials. However, as digital ultrasonic systems have evolved we have added new terminology to the field of nondestructive testing, such that phrases as Time of Flight are often misunderstood or over used. Conventional ultrasonic practice (meaning code based ultrasonic inspection) is in most reliant on the measurement of the reflected amplitude response to establish the presence and size of material discontinuities, where the time of flight is the measurement of the ultrasound as it travels to and from the reflector. This industry standard technique has on many occasions been questioned in terms of its value, especially during defect sizing applications. To address the known limitations of amplitude based sizing criteria, a new technique was developed referred to as Time Of Flight Diffraction -TOFD. Instead of using the amount of ultrasonic energy reflected by a discontinuity, TOFD relies on an aspect of ultrasonics that until more recently has been ignored or overlooked. This is the phenomena of diffracted ultrasonic energy, Using diffracted energy it is possible to more accurately measure the size of a defect. More recently the technique has been used for the detection of defects, where due to the imaging capabilities of the instrumentation used, TOFD has illustrated the presence of defects which could not be identified by other ultrasonic methods

A High-Precision RF Time-of-Flight Measurement Method based on Vernier Effect for Localization of Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Sang-il KO

2011-12-01

Full Text Available This paper presents the fundamental principles of a high-precision RF time-of-flight (ToF measurement method based on the vernier effect, which enables the improvement of time measurement resolution, for accurate distance measurement between sensor nodes in wireless sensor networks. Similar to the two scales of the vernier caliper, two heterogeneous clocks are employed to induce a new virtual time resolution that is much finer than clocks’ intrinsic time resolution. Consecutive RF signal transmission and sensing using two heterogeneous clocks generates a unique sensing pattern for the RF ToF, so that the size of the RF ToF can be estimated by comparing the measured sensing pattern with the predetermined sensing patterns for the RF ToF. RF ToF measurement experiments using this heterogeneous clock system, which has low operating frequencies of several megahertz, certify the proposed RF ToF measurement method through the evaluation of the measured sensing patterns with respect to an RF round-trip time of several nanoseconds.

REAL-TIME FLAVOUR TAGGING SELECTION IN ATLAS

CERN Document Server

Bokan, Petar; The ATLAS collaboration

2016-01-01

The ATLAS experiment includes a well-developed trigger system that allows a selection of events which are thought to be of interest, while achieving a high overall rejection against less interesting processes. An important part of the online event selection is the ability to distinguish between jets arising from heavy-flavour quarks (b- and c-jets) and light jets (jets from u-, d-, s- and gluon jets) in real-time. This is essential for many physics analysis that include processes with large jet multiplicity and b-quarks in the final state. Many changes were implemented to the ATLAS online b-jet selection for the Run-2 of the LHC. An overview of the b-jet trigger strategy and performance during 2015 data taking is presented. The ability to use complex offline Multivariate (MV2) b-tagging algorithms directly at High Level Trigger (HLT) was tested in this period. Details on online tagging algorithms are given together with the plans on how to adapt to the new high-luminosity and increased pileup conditions by ex...

Extracting Usage Patterns and the Analysis of Tag Connection Dynamics within Collaborative Tagging Systems

Directory of Open Access Journals (Sweden)

Daniel MICAN

2013-01-01

Full Text Available Collaborative tagging has become a very popular way of annotation, thanks to the fact that any entity may be labeled by any individual based on his own reason. In this paper we present the results of the case study carried out on the basis of data gathered at different time intervals from the social tagging system developed and implemented on Întelepciune.ro. Analyzing collective data referring to the way in which community members associate different tags, we have observed that between tags, links are formed which become increasingly stable with the passing of time. Following the application of methodology specific to network analysis, we have managed to extract information referring to tag popularity, their influence within the network and the degree to which a tag depends upon another. As such, we have succeeded in determining different semantic structures within the collective tagging system and see their evolution at different stages in time. Furthermore, we have pictured the way in which tag rec-ommendations can be executed and that they can be integrated within recommendation sys-tems. Thus, we will be able to identify experts and trustworthy content based on different cat-egories of interest.

Data acquisition system for a positron tomograph using time-of-flight information

International Nuclear Information System (INIS)

Bertin, Francois.

1981-12-01

Progress in nuclear instrumentation has led to the development of scintillators much faster than the NaI crystal traditionally used in nuclear medicine. As a result it is now possible to measure time-of-flight, i.e. the time between the arrival of two γ rays emitted in coincidence on two detectors. With this extra information the β + annihilation site may be located. The introduction of time-of-flight in tomographic techniques called for research along two lines: - ''theoretical'' research leading to the creation of a new image reconstruction algorithm taking into account time-of-flight information - applied research leading to the development of an efficient measurement line and sophisticated data acquisition and processing electronics. This research has been carried out at LETI and is briefly outlined in chapter I. Chapter II shows how the introduction of time-of-flight and the modification of the reconstruction algorithm complicate the electronic and informatic equipment of the tomograph. Several acquisition and processing strategies are proposed, then the need to use an intermediate mass storage and hence to design a complex acquisition operator is demonstrated. Chapter III examines the structure of the acquisition operator and the resulting block diagram is presented in detail in chapter IV [fr

10 ps resolution, 160 ns full scale range and less than 1.5% differential non-linearity time-to-digital converter module for high performance timing measurements

Energy Technology Data Exchange (ETDEWEB)

Markovic, B.; Tamborini, D.; Villa, F.; Tisa, S.; Tosi, A.; Zappa, F. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

2012-07-15

We present a compact high performance time-to-digital converter (TDC) module that provides 10 ps timing resolution, 160 ns dynamic range and a differential non-linearity better than 1.5% LSB{sub rms}. The TDC can be operated either as a general-purpose time-interval measurement device, when receiving external START and STOP pulses, or in photon-timing mode, when employing the on-chip SPAD (single photon avalanche diode) detector for detecting photons and time-tagging them. The instrument precision is 15 ps{sub rms} (i.e., 36 ps{sub FWHM}) and in photon timing mode it is still better than 70 ps{sub FWHM}. The USB link to the remote PC allows the easy setting of measurement parameters, the fast download of acquired data, and their visualization and storing via an user-friendly software interface. The module proves to be the best candidate for a wide variety of applications such as: fluorescence lifetime imaging, time-of-flight ranging measurements, time-resolved positron emission tomography, single-molecule spectroscopy, fluorescence correlation spectroscopy, diffuse optical tomography, optical time-domain reflectometry, quantum optics, etc.

Flavour tagging of $b$-mesons in $pp$ collisions at LHCb

CERN Document Server

Müller, Vanessa

2016-01-01

Flavour tagging, i.e. the inference of the production flavour of reconstructed B hadrons, is essen- tial for precision measurements of decay-time-dependent CP violation and of mixing parameters in the neutral B meson systems. At the LHC hadronic events create a challenging environment for flavour tagging and demand for new and improved strategies. We present recent progress and new developments in terms of the flavour tagging at the LHCb experiment, which will allow for a further improvement of CP violation measurements in neutral B meson decays.

Flavour tagging of $b$ mesons in $pp$ collisions at LHCb

CERN Multimedia

Mueller, Vanessa

2016-01-01

Flavour tagging, i.e. the inference of the production flavour of reconstructed $b$ hadrons, is essential for precision measurements of decay time-dependent $CP$ violation and of mixing parameters in the the neutral $B$ meson systems. LHC's $pp$ collisions with their high track multiplicities constitute a challenging environment for flavour tagging and demand for new and improved strategies. We present recent progress and new developments in flavour tagging at the LHCb experiment, which will allow for a further improvement of $CP$ violation measurements in decays of $B^0$ and $B_s^0$ mesons.

Understanding why users tag: A survey of tagging motivation literature and results from an empirical study.

Science.gov (United States)

Strohmaier, Markus; Körner, Christian; Kern, Roman

2012-12-01

While recent progress has been achieved in understanding the structure and dynamics of social tagging systems, we know little about the underlying user motivations for tagging, and how they influence resulting folksonomies and tags. This paper addresses three issues related to this question. (1) What distinctions of user motivations are identified by previous research, and in what ways are the motivations of users amenable to quantitative analysis? (2) To what extent does tagging motivation vary across different social tagging systems? (3) How does variability in user motivation influence resulting tags and folksonomies? In this paper, we present measures to detect whether a tagger is primarily motivated by categorizing or describing resources, and apply these measures to datasets from seven different tagging systems. Our results show that (a) users' motivation for tagging varies not only across, but also within tagging systems, and that (b) tag agreement among users who are motivated by categorizing resources is significantly lower than among users who are motivated by describing resources . Our findings are relevant for (1) the development of tag-based user interfaces, (2) the analysis of tag semantics and (3) the design of search algorithms for social tagging systems.

Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones

Science.gov (United States)

Gander, Philippa H.; Myhre, Grete; Graeber, R. Curtis; Lauber, John K.; Andersen, Harald T.

1989-01-01

The adjustment of sleep-wake patterns and the circadian temperature rhythm was monitored in nine Royal Norwegian Airforce volunteers operating P-3 aircraft during a westward training deployment across nine time zones. Subjects recorded all sleep and nap times, rated nightly sleep quality, and completed personality inventories. Rectal temperature, heart rate, and wrist activity were continuously monitored. Adjustment was slower after the return eastward flight than after the outbound westward flight. The eastward flight produced slower readjustment of sleep timing to local time and greater interindividual variability in the patterns of adjustment of sleep and temperature. One subject apparently exhibited resynchronization by partition, with the temperature rhythm undergoing the reciprocal 15-h delay. In contrast, average heart rates during sleep were significantly elevated only after westward flight. Interindividual differences in adjustment of the temperature rhythm were correlated with some of the personality measures. Larger phase delays in the overall temperature waveform (as measured on the 5th day after westward flight) were exhibited by extraverts, and less consistently by evening types.

Sensor-based material tagging system

International Nuclear Information System (INIS)

Vercellotti, L.C.; Cox, R.W.; Ravas, R.J.; Schlotterer, J.C.

1991-01-01

Electronic identification tags are being developed for tracking material and personnel. In applying electronic identification tags to radioactive materials safeguards, it is important to measure attributes of the material to ensure that the tag remains with the material. The addition of a microcontroller with an on-board analog-to-digital converter to an electronic identification tag application-specific integrated-circuit has been demonstrated as means to provide the tag with sensor data. Each tag is assembled into a housing, which serves as a scale for measuring the weight of a paint-can-sized container and its contents. Temperature rise of the can above ambient is also measured, and a piezoelectric detector detects disturbances and immediately puts the tag into its alarm and beacon mode. Radiation measurement was also considered, but the background from nearby containers was found to be excessive. The sensor-based tagging system allows tracking of the material in cans as it is stored in vaults or is moved through the manufacturing process. The paper presents details of the sensor-based material tagging system and describes a demonstration system

Discharge residence of TLD tagged fish

International Nuclear Information System (INIS)

Romberg, G.P.; Prepejchal, W.

1974-01-01

Although visual observations suggested that fish remained in the discharge for considerable periods, temperature-sensitive tags indicated the majority of fish spend less than 50 hr or 10 percent of the time at discharge temperatures. During 1974 a second fish tagging study was conducted, using temperature-sensitive tags to yield discharge residence times of Lake Michigan salmonids at Point Beach thermal discharge. Preliminary results revealed that many fish tag values were close to Unit I line indicating that calculated maximum discharge residence times for these fish will be nearly 100 percent of the elapsed time

The role of tag suggestions in folksonomies

NARCIS (Netherlands)

Bollen, D.G.F.M.; Halpin, H.

2009-01-01

Most tagging systems support the user in the tag selection process by providing tag suggestions, or recommendations, based on a popularity measurement of tags other users provided when tagging the same resource. The majority of theories and mathematical models of tagging found in the literature

Modelling the line shape of very low energy peaks of positron beam induced secondary electrons measured using a time of flight spectrometer

International Nuclear Information System (INIS)

Fairchild, A J; Chirayath, V A; Gladen, R W; Chrysler, M D; Koymen, A R; Weiss, A H

2017-01-01

In this paper, we present results of numerical modelling of the University of Texas at Arlington’s time of flight positron annihilation induced Auger electron spectrometer (UTA TOF-PAES) using SIMION® 8.1 Ion and Electron Optics Simulator. The time of flight (TOF) spectrometer measures the energy of electrons emitted from the surface of a sample as a result of the interaction of low energy positrons with the sample surface. We have used SIMION® 8.1 to calculate the times of flight spectra of electrons leaving the sample surface with energies and angles dispersed according to distribution functions chosen to model the positron induced electron emission process and have thus obtained an estimate of the true electron energy distribution. The simulated TOF distribution was convolved with a Gaussian timing resolution function and compared to the experimental distribution. The broadening observed in the simulated TOF spectra was found to be consistent with that observed in the experimental secondary electron spectra of Cu generated as a result of positrons incident with energy 1.5 eV to 901 eV, when a timing resolution of 2.3 ns was assumed. (paper)

Doppler time-of-flight imaging

KAUST Repository

Heidrich, Wolfgang; Heide, Felix; Wetzstein, Gordon; Hullin, Matthias

2017-01-01

Systems and methods for imaging object velocity are provided. In an embodiment, at least one Time-of-Flight camera is used to capture a signal representative of an object in motion over an exposure time. Illumination and modulation frequency

Ultrasonic divergent-beam scanner for time-of-flight tomography with computer evaluation

Energy Technology Data Exchange (ETDEWEB)

Glover, G H

1978-03-02

The rotatable ultrasonic divergent-beam scanner is designed for time-of-flight tomography with computer evaluation. With it there can be measured parameters that are of importance for the structure of soft tissues, e.g. time as a function of the velocity distribution along a certain path of flight(the method is analogous to the transaxial X-ray tomography). Moreover it permits to perform the quantitative measurement of two-dimensional velocity distributions and may therefore be applied to serial examinations for detecting cancer of the breast. As computers digital memories as well as analog-digital-hybrid systems are suitable.

Characterization of modulated time-of-flight range image sensors

Science.gov (United States)

Payne, Andrew D.; Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.

2009-01-01

A number of full field image sensors have been developed that are capable of simultaneously measuring intensity and distance (range) for every pixel in a given scene using an indirect time-of-flight measurement technique. A light source is intensity modulated at a frequency between 10-100 MHz, and an image sensor is modulated at the same frequency, synchronously sampling light reflected from objects in the scene (homodyne detection). The time of flight is manifested as a phase shift in the illumination modulation envelope, which can be determined from the sampled data simultaneously for each pixel in the scene. This paper presents a method of characterizing the high frequency modulation response of these image sensors, using a pico-second laser pulser. The characterization results allow the optimal operating parameters, such as the modulation frequency, to be identified in order to maximize the range measurement precision for a given sensor. A number of potential sources of error exist when using these sensors, including deficiencies in the modulation waveform shape, duty cycle, or phase, resulting in contamination of the resultant range data. From the characterization data these parameters can be identified and compensated for by modifying the sensor hardware or through post processing of the acquired range measurements.

Focusing procedures in time-of-flight mass spectrometry

International Nuclear Information System (INIS)

Ioanoviciu, D.

2002-01-01

Time-of-flight mass spectrometry is a fast growing field due to its ability to handle very fast processes and due to its theoretically unlimited mass range. The performances of the time-of-flight mass analysers are heavily dependent on the progress in ion optics, a periodically reviewed field. In this presentation the various focusing procedures in time-of-flight mass spectrometry are reviewed. For ions of the same charge and mass flight time differences result from different potentials at the location of formation and from the initial velocity spread. There is no simultaneous space and velocity focusing in time-of-flight mass spectrometry. Space focusing of first and second order can be reached in time-of-flight mass analysers having two homogeneous electric field ion sources followed by a field free space in front of the detector. Single and double stage homogeneous electric field mirrors can focus in time ions of different energies. These different energies result when ions leaving different initial sites and arriving simultaneously to an intermediate space focus. Convenient mass dispersion can be obtained by including a mirror. Initial velocity focusing is obtained by the delayed extraction procedure in drift space and mirror time-of-flight mass analysers. Post source pulse focusing aims at the same purpose. Ion source electrodes of hyperbolic shape, operated by high voltage pulses can bring major improvements of the resolution, especially at high masses. For each focusing procedure the geometric and/or electric conditions are given as well as the aberrations allowing the mass resolution determination. The various focusing procedures are compared and a prediction of their future performances was tempted. (author)

A technique for rapid source apportionment applied to ambient organic aerosol measurements from a thermal desorption aerosol gas chromatograph (TAG

Directory of Open Access Journals (Sweden)

Y. Zhang

2016-11-01

Full Text Available We present a rapid method for apportioning the sources of atmospheric organic aerosol composition measured by gas chromatography–mass spectrometry methods. Here, we specifically apply this new analysis method to data acquired on a thermal desorption aerosol gas chromatograph (TAG system. Gas chromatograms are divided by retention time into evenly spaced bins, within which the mass spectra are summed. A previous chromatogram binning method was introduced for the purpose of chromatogram structure deconvolution (e.g., major compound classes (Zhang et al., 2014. Here we extend the method development for the specific purpose of determining aerosol samples' sources. Chromatogram bins are arranged into an input data matrix for positive matrix factorization (PMF, where the sample number is the row dimension and the mass-spectra-resolved eluting time intervals (bins are the column dimension. Then two-dimensional PMF can effectively do three-dimensional factorization on the three-dimensional TAG mass spectra data. The retention time shift of the chromatogram is corrected by applying the median values of the different peaks' shifts. Bin width affects chemical resolution but does not affect PMF retrieval of the sources' time variations for low-factor solutions. A bin width smaller than the maximum retention shift among all samples requires retention time shift correction. A six-factor PMF comparison among aerosol mass spectrometry (AMS, TAG binning, and conventional TAG compound integration methods shows that the TAG binning method performs similarly to the integration method. However, the new binning method incorporates the entirety of the data set and requires significantly less pre-processing of the data than conventional single compound identification and integration. In addition, while a fraction of the most oxygenated aerosol does not elute through an underivatized TAG analysis, the TAG binning method does have the ability to achieve molecular level

Measurement of Neutron Energy Spectrum Emitted by Cf-252 Source Using Time-of-Flight Method

Energy Technology Data Exchange (ETDEWEB)

Lee, Cheol Ho; Son, Jaebum; Kim, Tae Hoon; Lee, Sangmin; Kim, Yong-Kyun [Hanyang University, Seoul (Korea, Republic of)

2016-10-15

The techniques proposed to detect the neutrons usually require the detection of a secondary recoiling nucleus in a scintillator (or other type of detector) to indicate the rare collision of a neutron with a nucleus. This is the same basic technique, in this case detection of a recoil proton that was used by Chadwick in the 1930 s to discover and identify the neutron and determine its mass. It is primary technique still used today for detection of fast neutron, which typically involves the use of a hydrogen based organic plastic or liquid scintillator coupled to a photo-multiplier tube. The light output from such scintillators is a function of the cross section and nuclear kinematics of the n + nucleus collision. With the exception of deuterated scintillators, the scintillator signal does not necessarily produce a distinct peak in the scintillator spectrum directly related to the incident neutron energy. Instead neutron time-of-flight (TOF) often must be utilized to determine the neutron energy, which requires generation of a prompt start signal from the nuclear source emitting the neutrons. This method takes advantage of the high number of prompt gamma rays. The Time-of-Flight method was used to measure neutron energy spectrum emitted by the Cf-252 neutron source. Plastic scintillator that has a superior discrimination ability of neutron and gamma-ray was used as a stop signal detector and liquid scintillator was used as a stat signal detector. In experiment, neutron and gamma-ray spectrum was firstly measured and discriminated using the TOF method. Secondly, neutron energy spectrum was obtained through spectrum analysis. Equation of neutron energy spectrum that was emitted by Cf-252 source using the Gaussian fitting was obtained.

Single view reflectance capture using multiplexed scattering and time-of-flight imaging

OpenAIRE

Zhao, Shuang; Velten, Andreas; Raskar, Ramesh; Bala, Kavita; Naik, Nikhil Deepak

2011-01-01

This paper introduces the concept of time-of-flight reflectance estimation, and demonstrates a new technique that allows a camera to rapidly acquire reflectance properties of objects from a single view-point, over relatively long distances and without encircling equipment. We measure material properties by indirectly illuminating an object by a laser source, and observing its reflected light indirectly using a time-of-flight camera. The configuration collectively acquires dense angular, but l...

Time Manager Software for a Flight Processor

Science.gov (United States)

Zoerne, Roger

2012-01-01

Data analysis is a process of inspecting, cleaning, transforming, and modeling data to highlight useful information and suggest conclusions. Accurate timestamps and a timeline of vehicle events are needed to analyze flight data. By moving the timekeeping to the flight processor, there is no longer a need for a redundant time source. If each flight processor is initially synchronized to GPS, they can freewheel and maintain a fairly accurate time throughout the flight with no additional GPS time messages received. How ever, additional GPS time messages will ensure an even greater accuracy. When a timestamp is required, a gettime function is called that immediately reads the time-base register.

Analysis of tag-position bias in MPSS technology

Directory of Open Access Journals (Sweden)

Rattray Magnus

2006-04-01

Full Text Available Abstract Background Massively Parallel Signature Sequencing (MPSS technology was recently developed as a high-throughput technology for measuring the concentration of mRNA transcripts in a sample. It has previously been observed that the position of the signature tag in a transcript (distance from 3' end can affect the measurement, but this effect has not been studied in detail. Results We quantify the effect of tag-position bias in Classic and Signature MPSS technology using published data from Arabidopsis, rice and human. We investigate the relationship between measured concentration and tag-position using nonlinear regression methods. The observed relationship is shown to be broadly consistent across different data sets. We find that there exist different and significant biases in both Classic and Signature MPSS data. For Classic MPSS data, genes with tag-position in the middle-range have highest measured abundance on average while genes with tag-position in the high-range, far from the 3' end, show a significant decrease. For Signature MPSS data, high-range tag-position genes tend to have a flatter relationship between tag-position and measured abundance. Thus, our results confirm that the Signature MPSS method fixes a substantial problem with the Classic MPSS method. For both Classic and Signature MPSS data there is a positive correlation between measured abundance and tag-position for low-range tag-position genes. Compared with the effects of mRNA length and number of exons, tag-position bias seems to be more significant in Arabadopsis. The tag-position bias is reflected both in the measured abundance of genes with a significant tag count and in the proportion of unexpressed genes identified. Conclusion Tag-position bias should be taken into consideration when measuring mRNA transcript abundance using MPSS technology, both in Classic and Signature MPSS methods.

The measurement programme at the neutron time-of-flight facility n_TOF at CERN

Directory of Open Access Journals (Sweden)

Gunsing F.

2017-01-01

Full Text Available Neutron-induced reaction cross sections are important for a wide variety of research fields ranging from the study of nuclear level densities, nucleosynthesis to applications of nuclear technology like design, and criticality and safety assessment of existing and future nuclear reactors, radiation dosimetry, medical applications, nuclear waste transmutation, accelerator-driven systems and fuel cycle investigations. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. CERN’s neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2001. While for a long period a single measurement station (EAR1 located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2 in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at n_TOF will be presented.

A novel particle time of flight diagnostic for measurements of shock- and compression-bang times in D3He and DT implosions at the NIF.

Science.gov (United States)

Rinderknecht, H G; Johnson, M Gatu; Zylstra, A B; Sinenian, N; Rosenberg, M J; Frenje, J A; Waugh, C J; Li, C K; Sèguin, F H; Petrasso, R D; Rygg, J R; Kimbrough, J R; MacPhee, A; Collins, G W; Hicks, D; Mackinnon, A; Bell, P; Bionta, R; Clancy, T; Zacharias, R; Döppner, T; Park, H S; LePape, S; Landen, O; Meezan, N; Moses, E I; Glebov, V U; Stoeckl, C; Sangster, T C; Olson, R; Kline, J; Kilkenny, J

2012-10-01

The particle-time-of-flight (pTOF) diagnostic, fielded alongside a wedge range-filter (WRF) proton spectrometer, will provide an absolute timing for the shock-burn weighted ρR measurements that will validate the modeling of implosion dynamics at the National Ignition Facility (NIF). In the first phase of the project, pTOF has recorded accurate bang times in cryogenic DT, DT exploding pusher, and D(3)He implosions using DD or DT neutrons with an accuracy better than ±70 ps. In the second phase of the project, a deflecting magnet will be incorporated into the pTOF design for simultaneous measurements of shock- and compression-bang times in D(3)He-filled surrogate implosions using D(3)He protons and DD-neutrons, respectively.

Study and realization of a parallel plate avalanche counter used for time of flight and localization measurements

International Nuclear Information System (INIS)

Pellegrin, P.O.

1985-01-01

A parallel Plates Avalanche Counter (P.P.A.C.) allowing high resolution training and localization is studied. It is designed to be placed on the beam trajectory-including the magnetic spectrometer of SARA accelerator at ISN Grenoble. Two purposes are searched: firstly to improve the time-of-flight measurement due to the very high intrinsic time resolution (it can be less than 150 ps), secondly to measure with accuracy the scattering angle of the particle on the target, due to its localization. The detector thickness has been reduced to set aside as unimportant the disturbance produced on the particle trajectory. The theoretical aspect of the detector operation and a quantitative study of the disturbances it causes on particle energy are presented. The set-up and its necessary surroundings are described with experimental results of its characteristics [fr

New development for the reverse time of flight analysis of spectra measured using Fourier Diffractometer Facilities

CERN Document Server

Maayouf, R M A

2002-01-01

The present work introduces a new design to replace the (Finnish make) reverse time of flight (RTOF) analyzer used for the Fourier diffractometer facilities. The new design applies a data acquisition system, a special interface card and software program installed in a PC computer, to perform the cross-correlation functions between signals received from the chopper-decoder and detector. It has been found from test measurements performed with the Cairo Fourier diffractometer facility (CFDF) and the similar high resolution one at JINR (Dubna-Russia) that the new design can successfully replace the Finnish make RTOF analyzer.

Concept design of a time-of-flight spectrometer for the measurement of the energy of alpha particles.

Science.gov (United States)

García-Toraño, E

2018-04-01

The knowledge of the energies of the alpha particles emitted in the radioactive decay of a nuclide is a key factor in the construction of its decay scheme. Virtually all existing data are based on a few absolute measurements made by magnetic spectrometry (MS), to which most other MS measurements are traced. An alternative solution would be the use of time-of-flight detectors. This paper discusses the main aspects to be considered in the design of such detectors, and the performances that could be reasonably expected. Based on the concepts discussed here, it is estimated that an energy resolution about 2.5keV may be attainable with a good quality source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of "same side" flavour tagging algorithms for measurements of flavour oscillations and $CP$ violation in the $B^0$ mesons system

CERN Document Server

Fazzini, Davide; Khanji, Basem

In this thesis new developments of $\\textit{Flavour Tagging}$ algorithms for the $LHCb$ experiment are presented. The $\\textit{Flavour Tagging}$ is a very usefull tool which allows to determine the flavour of the reconstructed particles, such as the $B^0$ mesons. A correctly identification of the flavour is fundamental in certain measurements such as time-dependent $CP$ violation asymmetries or the $B^0 \\leftrightarrow \\overline{B}^0$ oscillations. Both these type of measurements are exploited by LHCb experiment in the research of new physics beyond the Standard Model. The new developments achieved in this work concern an optimization of the $\\textit{Same Side Tagger}$ algorithms, using protons and pions correlated in charge with the signal $B^0$ to infer its initial flavour. Then two combinations are implemented: the first is a combination of the $\\textit{SS Pion Tagger}$ ($SS\\pi$) and the $\\textit{SS Proton Tagger}$ ($SSp$) in a unique $\\textit{Same Side}$ ($SS$) tagging algorithm; the second one is the fi...

Testing the time-of-flight model for flagellar length sensing.

Science.gov (United States)

Ishikawa, Hiroaki; Marshall, Wallace F

2017-11-07

Cilia and flagella are microtubule-based organelles that protrude from the surface of most cells, are important to the sensing of extracellular signals, and make a driving force for fluid flow. Maintenance of flagellar length requires an active transport process known as intraflagellar transport (IFT). Recent studies reveal that the amount of IFT injection negatively correlates with the length of flagella. These observations suggest that a length-dependent feedback regulates IFT. However, it is unknown how cells recognize the length of flagella and control IFT. Several theoretical models try to explain this feedback system. We focused on one of the models, the "time-of-flight" model, which measures the length of flagella on the basis of the travel time of IFT protein in the flagellar compartment. We tested the time-of-flight model using Chlamydomonas dynein mutant cells, which show slower retrograde transport speed. The amount of IFT injection in dynein mutant cells was higher than that in control cells. This observation does not support the prediction of the time-of-flight model and suggests that Chlamydomonas uses another length-control feedback system rather than that described by the time-of-flight model. © 2017 Ishikawa and Marshall. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

High sensitivity probe absorption technique for time-of-flight ...

Indian Academy of Sciences (India)

Abstract. We report on a phase-sensitive probe absorption technique with high sen- sitivity, capable of detecting a few hundred ultra-cold atoms in flight in an observation time of a few milliseconds. The large signal-to-noise ratio achieved is sufficient for reliable measurements on low intensity beams of cold atoms.

Measurement of liquid sheet using laser tagging method by photochromic dye

Science.gov (United States)

Rosli, Nurrina Binti; Amagai, Kenji

2014-12-01

Liquid atomization system has been extensively applied as the most significant process in many industrial fields. In the internal combustion engine, the combustion phenomenon is strongly influenced by the spray characteristics of the fuel given by the atomization process. In order to completely understand the whole atomization process, a detail investigation of relations between the liquid jet characteristics and the breakup phenomenon is required. In this study, a non-intrusive method called as laser tagging method by photochromic dye has been developed with aim to study the breakup process of liquid sheet in detail, covering from the behavior in film until disintegrated into ligament and droplets. The laser tagging method by photochromic dye is based on a shift in the absorption spectrum of photochromic dye molecules tagged by ultraviolet laser. The shift results a color change at the tagged region of liquid containing the dye. In this study, the motions of the dye traces were analyzed as the liquid surface velocity. As a result, liquid sheet was found to keep its velocity constantly in film before suddenly increase around broken point. However, it then decreased after broken into droplets. By forming a set of four points of dye traces on the liquid sheet, the change of relative position of the set enabled the measurement of deformation and rotational motion of the liquid sheet. As a result, the normal strain of the liquid sheet parallel to the flow direction depended on the flow behavior of ligament formation.

A time-focusing Fourier chopper time-of-flight diffractometer for large scattering angles

International Nuclear Information System (INIS)

Heinonen, R.; Hiismaeki, P.; Piirto, A.; Poeyry, H.; Tiitta, A.

1975-01-01

A high-resolution time-of-flight diffractometer utilizing time focusing principles in conjunction with a Fourier chopper is under construction at Otaniemi. The design is an improved version of a test facility which has been used for single-crystal and powder diffraction studies with promising results. A polychromatic neutron beam from a radial beam tube of the FiR 1 reactor, collimated to dia. 70 mm, is modulated by a Fourier chopper (dia. 400 mm) which is placed inside a massive boron-loaded particle board shielding of 900 mm wall thickness. A thin flat sample (5 mm x dia. 80 mm typically) is mounted on a turntable at a distance of 4 m from the chopper, and the diffracted neutrons are counted by a scintillation detector at 4 m distance from the sample. The scattering angle 2theta can be chosen between 90deg and 160deg to cover Bragg angles from 45deg up to 80deg. The angle between the chopper disc and the incident beam direction as well as the angle of the detector surface relative to the diffracted beam can be adjusted between 45deg and 90deg in order to accomplish time-focusing. In our set-up, with equal flight paths from chopper to sample and from sample to detector, the time-focusing conditions are fulfilled when the chopper and the detector are parallel to the sample-plane. The time-of-flight spectrum of the scattered neutrons is measured by the reverse time-of-flight method in which, instead of neutrons, one essentially records the modulation function of the chopper during constant periods preceding each detected neutron. With a Fourier chopper whose speed is varied in a suitable way, the method is equivalent to the conventional Fourier method but the spectrum is obtained directly without any off-line calculations. The new diffractometer is operated automatically by a Super Nova computer which not only accumulates the synthetized diffraction pattern but also controls the chopper speed according to the modulation frequency sweep chosen by the user to obtain a

Time-of-Flight Positron Emission Tomography with Radiofrequency Phototube

International Nuclear Information System (INIS)

Margaryan, A.; Kakoyan, V.; Knyazyan, S.

2011-01-01

In this paper γ-detector, based on the radiofrequency (RF) phototube and recently developed fast and ultrafast scintillators, is considered for Time-of-Flight positron emission tomography applications. Timing characteristics of such a device has been investigated by means of a dedicated Monte Carlo code based on the single photon counting concept. Biexponential timing model for scintillators have been used. The calculations have shown that such a timing model is in a good agreement with recently measured data. The timing resolution of -detectors can be significantly improved by using the RF phototube. (authors)

Computationally effective solution of the inverse problem in time-of-flight spectroscopy

DEFF Research Database (Denmark)

Kamran, Faisal; Abildgaard, Otto Højager Attermann; Subash, Arman Ahamed

2015-01-01

Photon time-of-flight (PTOF) spectroscopy enables the estimation of absorption and reduced scattering coefficients of turbid media by measuring the propagation time of short light pulses through turbid medium. The present investigation provides a comparison of the assessed absorption and reduced...

First Direct Mass Measurements of Nuclides around Z =100 with a Multireflection Time-of-Flight Mass Spectrograph

Science.gov (United States)

Ito, Y.; Schury, P.; Wada, M.; Arai, F.; Haba, H.; Hirayama, Y.; Ishizawa, S.; Kaji, D.; Kimura, S.; Koura, H.; MacCormick, M.; Miyatake, H.; Moon, J. Y.; Morimoto, K.; Morita, K.; Mukai, M.; Murray, I.; Niwase, T.; Okada, K.; Ozawa, A.; Rosenbusch, M.; Takamine, A.; Tanaka, T.; Watanabe, Y. X.; Wollnik, H.; Yamaki, S.

2018-04-01

The masses of 246Es, 251Fm, and the transfermium nuclei Md-252249 and 254No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N =152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of 246Es and 249,250,252Md were measured for the first time. Using the masses of Md,250249 as anchor points for α decay chains, the masses of heavier nuclei, up to 261Bh and 266Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ2 n derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N =152 neutron shell closure for Md and Lr.

Time-of-flight neutron diffractometer for monocrystal study

International Nuclear Information System (INIS)

Anan'ev, B.N.; Balagurov, A.M.; Barabash, I.P.; Georgiu, Z.; Shibaev, V.D.

1979-01-01

The design of a neutron diffractometer is discussed. It is used for structural analysis of single crystals on the basis of time-of-flight measurements. The diffractometer is positioned along the axis of a beam of the IBR-30 pulse reactor, its average power is 29 kW. The mechanical part of the diffractometer consists of a massive foundation with a threeaxial goniometer, a rotatable platform with a collimator and a 3 He counter. The flowsheet of a control unit is given, which is used to position the rotatable platform of the diffractometer. The control unit includes a 14 digic binary counter for rotation angle recording, a parallel-to-series converter, a control signal shaper, two position shift registers, and a servo mechanism. The accuracy of diffraction maxima is evaluated. It is found that the ratio D(t)sup(1/2)/t (D(t) is a time dispersion of diffraction maxima, t is total time-of-flight time), which characterize the resolution of the diffractometer, is equal to 0.5% at the Bragg angle Q=45 deg and the neutron wavelength Λ=1 A

The TORCH time-of-flight detector

Energy Technology Data Exchange (ETDEWEB)

Harnew, N., E-mail: Neville.Harnew@physics.ox.ac.uk [University of Oxford, Denys Wilkinson Building, 1 Keble Road, Oxford OX1 3RH (United Kingdom); Brook, N. [University College London, Department of Physics & Astronomy, Gower Street, London WC1E 6BT (United Kingdom); Castillo García, L. [CERN, PH Department, CH-1211 Geneva 23 (Switzerland); Laboratory for High Energy Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Cussans, D. [H.H. Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL (United Kingdom); Föhl, K.; Forty, R.; Frei, C. [CERN, PH Department, CH-1211 Geneva 23 (Switzerland); Gao, R. [University of Oxford, Denys Wilkinson Building, 1 Keble Road, Oxford OX1 3RH (United Kingdom); Gys, T.; Piedigrossi, D. [CERN, PH Department, CH-1211 Geneva 23 (Switzerland); Rademacker, J.; Ros Garcia, A.; Dijk, M. van [H.H. Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL (United Kingdom)

2016-07-11

The TORCH time-of-flight detector is being developed to provide particle identification between 2 and 10 GeV/c momentum over a flight distance of 10 m. TORCH is designed for large-area coverage, up to 30 m{sup 2}, and has a DIRC-like construction. The goal is to achieve a 15 ps time-of-flight resolution per incident particle by combining arrival times from multiple Cherenkov photons produced within quartz radiator plates of 10 mm thickness. A four-year R&D programme is underway with an industrial partner (Photek, UK) to produce 53×53 mm{sup 2} Micro-Channel Plate (MCP) detectors for the TORCH application. The MCP-PMT will provide a timing accuracy of 40 ps per photon and it will have a lifetime of up to at least 5 Ccm{sup −2} of integrated anode charge by utilizing an Atomic Layer Deposition (ALD) coating. The MCP will be read out using charge division with customised electronics incorporating the NINO chipset. Laboratory results on prototype MCPs are presented. The construction of a prototype TORCH module and its simulated performance are also described.

Direct mass measurements in the light neutron-rich region using a combined energy and time-of-flight technique

International Nuclear Information System (INIS)

Pillai, C.; Swenson, L.W.; Vieira, D.J.; Butler, G.W.; Wouters, J.M.; Rokni, S.H.; Vaziri, K.; Remsberg, L.P.

1985-01-01

This experiment has demonstrated that direct mass measurements can be performed (albeit of low precision in this first attempt) using the M proportional to ET 2 method. This technique has the advantage that many particle-bound nuclei, produced in fragmentation reactions can be measured simultaneously, independent of their N or Z. The main disadvantage of this approach is that both energy and time-of-flight must be measured precisely on an absolute scale. Although some mass walk with N and Z was observed in this experiment, these uncertainties were largely removed by extrapolating the smooth dependence observed for known nuclei which lie closer to the valley of β-stability. Mass measurements for several neutron-rich light nuclei ranging from 17 C to 26 Ne have been performed. In all cases these measurements agree with the latest mass compilation of Wapstra and Audi. The masses of 20 N and 24 F have been determined for the first time

Real-time In-Flight Strain and Deflection Monitoring with Fiber Optic Sensors

Science.gov (United States)

Richards, Lance; Parker, Allen R.; Ko, William L.; Piazza, Anthony

2008-01-01

This viewgraph presentation reviews Dryden's efforts to develop in-flight monitoring based on Fiber Optics. One of the motivating factors for this development was the breakup of the Helios aircraft. On Ikhana the use of fiber optics for wing shape sensing is being developed. They are being used to flight validate fiber optic sensor measurements and real-time wing shape sensing predictions on NASA's Ikhana vehicle; validate fiber optic mathematical models and design tools; Assess technical viability and, if applicable, develop methodology and approach to incorporate wing shape measurements within the vehicle flight control system, and develop and flight validate advanced approaches to perform active wing shape control.

Development of an ion time-of-flight spectrometer for neutron depth profiling

Science.gov (United States)

Cetiner, Mustafa Sacit

Ion time-of-flight spectrometry techniques are investigated for applicability to neutron depth profiling. Time-of-flight techniques are used extensively in a wide range of scientific and technological applications including energy and mass spectroscopy. Neutron depth profiling is a near-surface analysis technique that gives concentration distribution versus depth for certain technologically important light elements. The technique uses thermal or sub-thermal neutrons to initiate (n, p) or (n, alpha) reactions. Concentration versus depth distribution is obtained by the transformation of the energy spectrum into depth distribution by using stopping force tables of the projectiles in the substrate, and by converting the number of counts into concentration using a standard sample of known dose value. Conventionally, neutron depth profiling measurements are based on charged particle spectrometry, which employs semiconductor detectors such as a surface barrier detector (SBD) and the associated electronics. Measurements with semiconductor detectors are affected by a number of broadening mechanisms, which result from the interactions between the projectile ion and the detector material as well as fluctuations in the signal generation process. These are inherent features of the detection mechanism that involve the semiconductor detectors and cannot be avoided. Ion time-of-flight spectrometry offers highly precise measurement capabilities, particularly for slow particles. For high-energy low-mass particles, measurement resolution tends to degrade with all other parameters fixed. The threshold for more precise ion energy measurements with respect to conventional techniques, such as direct energy measurement by a surface barrier detector, is directly related to the design and operating parameters of the device. Time-of-flight spectrometry involves correlated detection of two signals by a coincidence unit. In ion time-of-flight spectroscopy, the ion generates the primary input

RAMSES - Rapid Measurement and Special Environment time-of-flight Spectrometer

International Nuclear Information System (INIS)

Schober, H.; Koza, M.; Mutka, H.; Zbiri, M.; Andersen, K.

2011-01-01

Time-of-flight spectrometers are ideally suited to study the dynamics of complex materials as encountered in all domains of current scientific interest ranging from health care, biology, earth and environmental sciences, cultural heritage to energy storage and preservation. Complex materials are often available in samples of small amount, or the scientific questions to study require environments limiting the sample size (e.g., Paris-Edinburgh cells and levitation furnaces). The proposed instrument would be optimized for these conditions offering a very high neutron flux over a small beam cross-section in combination with good resolution and extended dynamical range. The later asks for a wavelength band extending slightly into the thermal region. This is achieved on a cold guide with super-mirror coating. (authors)

A beam profile monitor for a tagged photon beam

International Nuclear Information System (INIS)

Arends, J.; Breuer, M.; Dahmen, H.D.; Detemple, P.; Noeldeke, G.; Schneider, W.; Zucht, B.

1990-10-01

A beam profile monitor for electron and photon beams is described, which operates at the low intensities encountered in a tagged bremsstrahlung beam environment, typically 10 10 electrons/s and 10 7 photons/s. The method is based on a wire scanner and utilizes the presence of a tagging spectrometer. The accuracy of the measurements can be tuned in a wide range (at the expense of measuring time) to meet the requirements set by the actual beam size. Examples of measured electron and photon beam profiles at the tagged photon beam of the PHOENICS experiment at the electron stretcher ring ELSA are given. (orig.)

A beam profile monitor for a tagged photon beam

Energy Technology Data Exchange (ETDEWEB)

Arends, J.; Breuer, M.; Dahmen, H.D.; Detemple, P.; Noeldeke, G.; Schneider, W.; Zucht, B.

1990-10-01

A beam profile monitor for electron and photon beams is described, which operates at the low intensities encountered in a tagged bremsstrahlung beam environment, typically 10{sup 10} electrons/s and 10{sup 7} photons/s. The method is based on a wire scanner and utilizes the presence of a tagging spectrometer. The accuracy of the measurements can be tuned in a wide range (at the expense of measuring time) to meet the requirements set by the actual beam size. Examples of measured electron and photon beam profiles at the tagged photon beam of the PHOENICS experiment at the electron stretcher ring ELSA are given. (orig.).

[Separation and identification of bovine lactoferricin by high performance liquid chromatography-matrix-assisted laser desorption/ionization time of flight/ time of flight mass spectrometry].

Science.gov (United States)

An, Meichen; Liu, Ning

2010-02-01

A high performance liquid chromatography-matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry (HPLC-MALDI-TOF/TOF MS) method was developed for the separation and identification of bovine lactoferricin (LfcinB). Bovine lactoferrin was hydrolyzed by pepsin and then separated by ion exchange chromatography and reversed-phase liquid chromatography (RP-LC). The antibacterial activities of the fractions from RP-LC separation were determined and the protein concentration of the fraction with the highest activity was measured, whose sequence was indentified by MALDI-TOF/TOF MS. The relative molecular mass of LfcinB was 3 124.89 and the protein concentration was 18.20 microg/mL. The method of producing LfcinB proposed in this study has fast speed, high accuracy and high resolution.

Doubly tagged delayed-choice tunable quantum eraser: coherence, information and measurement

Science.gov (United States)

Imran, Muhammad; Tariq, Hinna; Rameez-ul-Islam; Ikram, Manzoor

2018-01-01

We present an idea for the doubly tagged delayed-choice tunable quantum eraser in a cavity QED setup, based on fully controlled resonant as well as dispersive atom-field interactions. Two cavity fields, bound initially in the Bell state, are coupled to a three-level atom. Such an atom is initially prepared in the coherent superposition of the lower two levels and is quite capable of exhibiting Ramsey fringes if taken independently. It is shown that the coherence lost due to tagging can not only be retrieved but that the fringe visibility/path distinguishability can also be conditionally tuned in a delayed manner through local manipulation of the entangled cavity fields. The stringent condition here is the retainment of the system’s coherence during successive manipulations of the individual cavity fields. Such a quantum eraser, therefore, prominently highlights the links among all the counterintuitive features of quantum theory including the conception of time, measurement, state vector reduction, coherence and information in an unambiguous manner. The schematics can be straightforwardly extended to a multipartite scenario and employed to explore multi-player quantum games with the payoff being strangely decided through delayed choice setups.

Instantaneous Tunneling Flight Time for Wavepacket Transmission through Asymmetric Barriers.

Science.gov (United States)

Petersen, Jakob; Pollak, Eli

2018-04-12

The time it takes a particle to tunnel through the asymmetric Eckart barrier potential is investigated using Gaussian wavepackets, where the barrier serves as a model for the potential along a chemical reaction coordinate. We have previously shown that the, in principle experimentally measurable, tunneling flight time, which determines the time taken by the transmitted particle to traverse the barrier, vanishes for symmetric potentials like the Eckart and square barrier [ Petersen , J. ; Pollak , E. J. Phys. Chem. Lett. 2017 , 9 , 4017 ]. Here we show that the same result is obtained for the asymmetric Eckart barrier potential, and therefore, the zero tunneling flight time seems to be a general result for one-dimensional time-independent potentials. The wavepacket dynamics is simulated using both an exact quantum mechanical method and a classical Wigner prescription. The excellent agreement between the two methods shows that quantum coherences are not important in pure one-dimensional tunneling and reinforces the conclusion that the tunneling flight time vanishes.

Analytical properties of time-of-flight PET data

Energy Technology Data Exchange (ETDEWEB)

Cho, Sanghee; Ahn, Sangtae; Quanzheng, Li; Leahy, Richard M [Signal and Image Processing Institute, University of Southern California, Los Angeles, CA 90089 (United States)], E-mail: leahy@sipi.usc.edu

2008-06-07

We investigate the analytical properties of time-of-flight (TOF) positron emission tomography (PET) sinograms, where the data are modeled as line integrals weighted by a spatially invariant TOF kernel. First, we investigate the Fourier transform properties of 2D TOF data and extend the 'bow-tie' property of the 2D Radon transform to the time-of-flight case. Second, we describe a new exact Fourier rebinning method, TOF-FOREX, based on the Fourier transform in the time-of-flight variable. We then combine TOF-FOREX rebinning with a direct extension of the projection slice theorem to TOF data, to perform fast 3D TOF PET image reconstruction. Finally, we illustrate these properties using simulated data.

Analytical properties of time-of-flight PET data

Science.gov (United States)

Cho, Sanghee; Ahn, Sangtae; Li, Quanzheng; Leahy, Richard M.

2008-06-01

We investigate the analytical properties of time-of-flight (TOF) positron emission tomography (PET) sinograms, where the data are modeled as line integrals weighted by a spatially invariant TOF kernel. First, we investigate the Fourier transform properties of 2D TOF data and extend the 'bow-tie' property of the 2D Radon transform to the time-of-flight case. Second, we describe a new exact Fourier rebinning method, TOF-FOREX, based on the Fourier transform in the time-of-flight variable. We then combine TOF-FOREX rebinning with a direct extension of the projection slice theorem to TOF data, to perform fast 3D TOF PET image reconstruction. Finally, we illustrate these properties using simulated data.

Analytical properties of time-of-flight PET data

International Nuclear Information System (INIS)

Cho, Sanghee; Ahn, Sangtae; Li Quanzheng; Leahy, Richard M

2008-01-01

We investigate the analytical properties of time-of-flight (TOF) positron emission tomography (PET) sinograms, where the data are modeled as line integrals weighted by a spatially invariant TOF kernel. First, we investigate the Fourier transform properties of 2D TOF data and extend the 'bow-tie' property of the 2D Radon transform to the time-of-flight case. Second, we describe a new exact Fourier rebinning method, TOF-FOREX, based on the Fourier transform in the time-of-flight variable. We then combine TOF-FOREX rebinning with a direct extension of the projection slice theorem to TOF data, to perform fast 3D TOF PET image reconstruction. Finally, we illustrate these properties using simulated data

Analytical properties of time-of-flight PET data

Energy Technology Data Exchange (ETDEWEB)

Cho, Sanghee; Ahn, Sangtae; Li Quanzheng; Leahy, Richard M [Signal and Image Processing Institute, University of Southern California, Los Angeles, CA 90089 (United States)], E-mail: leahy@sipi.usc.edu

2008-06-07

We investigate the analytical properties of time-of-flight (TOF) positron emission tomography (PET) sinograms, where the data are modeled as line integrals weighted by a spatially invariant TOF kernel. First, we investigate the Fourier transform properties of 2D TOF data and extend the 'bow-tie' property of the 2D Radon transform to the time-of-flight case. Second, we describe a new exact Fourier rebinning method, TOF-FOREX, based on the Fourier transform in the time-of-flight variable. We then combine TOF-FOREX rebinning with a direct extension of the projection slice theorem to TOF data, to perform fast 3D TOF PET image reconstruction. Finally, we illustrate these properties using simulated data.

Use of high performance networks and supercomputers for real-time flight simulation

Science.gov (United States)

Cleveland, Jeff I., II

1993-01-01

In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be consistent in processing time and be completed in as short a time as possible. These operations include simulation mathematical model computation and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to the Computer Automated Measurement and Control (CAMAC) technology which resulted in a factor of ten increase in the effective bandwidth and reduced latency of modules necessary for simulator communication. This technology extension is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC are completing the development of the use of supercomputers for mathematical model computation to support real-time flight simulation. This includes the development of a real-time operating system and development of specialized software and hardware for the simulator network. This paper describes the data acquisition technology and the development of supercomputing for flight simulation.

A Measurement of the Parity Violating Parameter Ab with a Muon Tag at the SLD

Energy Technology Data Exchange (ETDEWEB)

Bellodi, Giulia

2001-02-12

We present a direct measurement of the parity violation parameter A{sub b}, derived from the left-right forward-backward asymmetry of b quarks tagged via muons from semileptonic decays. The value of A{sub b} is extracted using a maximum likelihood fit to the differential cross section for fermion production. The novelty of this measurement consists in the use of topological vertexing information alongside the more traditional decay kinematics to discriminate among the different sources of tagged leptons. The small and stable SLC beam spot and the CCD based vertex detector are used to reconstruct secondary decay vertices and to provide precise kinematic information and a highly efficient and pure B mass tag. A multivariate approach has been used, with a total of 4 tagging variables, whose correlation with each other has been taken into account. The final result has been cross-checked both with a classical cut-and-count method and combining all the information into a neural net. Based on the full SLD dataset of 550K Z{sup 0} events with highly polarized electron beams, this measurement represents an improvement of a factor of 2 with respect to the previously published result (1993-1995 only and with no vertexing information). The statistical sensitivity achieved is around 4% for A{sub b}, making this a world-class single measurement. An estimate of A{sub c} has been simultaneously derived from a common fit, with a precision of about 10%.

Flavour Tagging with the LHCb experiment

CERN Multimedia

Birnkraut, Alex

2015-01-01

Measurements of flavour oscillations and time-dependent CP asymmetries in neutral B meson systems require knowledge of the b quark production flavour. This identification is performed by the Flavour Tagging.

High performance real-time flight simulation at NASA Langley

Science.gov (United States)

Cleveland, Jeff I., II

1994-01-01

In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be deterministic and be completed in as short a time as possible. This includes simulation mathematical model computational and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, personnel at NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to a standard input/output system to provide for high bandwidth, low latency data acquisition and distribution. The Computer Automated Measurement and Control technology (IEEE standard 595) was extended to meet the performance requirements for real-time simulation. This technology extension increased the effective bandwidth by a factor of ten and increased the performance of modules necessary for simulator communications. This technology is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications of this technology are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC have completed the development of the use of supercomputers for simulation mathematical model computational to support real-time flight simulation. This includes the development of a real-time operating system and the development of specialized software and hardware for the CAMAC simulator network. This work, coupled with the use of an open systems software architecture, has advanced the state of the art in real time flight simulation. The data acquisition technology innovation and experience with recent developments in this technology are described.

Mass measurements of {sup 238}U-projectile fragments for the first time with a multiple-reflection time-of-flight mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Ebert, Jens

2016-07-01

Mass measurements of short-lived uranium projectile fragments were performed for the first time with a Multiple-Reflexion-Time-of-Flight Mass Spectrometer (MR-TOF-MS). A major part of this doctoral work was a novel development of a data analysis method for the MR-TOF-MS mass measurements of exotic nuclei at the fragment separator FRS at GSI. The developed method was successfully applied to the data obtained from two pilot experiments with the MR-TOF-MS at the FRS in 2012 and 2014. A substantial upgrade of the experimental setup of the MR-TOF-MS was also performed in the frame work of this doctoral thesis after the first run. In the experiments projectile fragments were created with 1000 MeV/u {sup 238}U ions in a Be/Nb target at the entrance of the in-flight separator FRS. The exotic nuclei were spatially separated, energy bunched and slowed down with the ion-optical system of the FRS combined with monoenergetic and homogeneous degraders. At the final focal plane of the FRS the fragments were completely slowed down and thermalized in a cryogenic stopping cell (CSC) filled with 3-5 mg/cm{sup 2} pure helium gas. The exotic nuclei were fast extracted from the CSC to enable mass measurements of very short-lived fragments with the MR-TOF-MS. The achievement of this goal was successfully demonstrated with the mass measurement of {sup 220}Ra ions with a half-life of 17.9 ms and 11 detected events. The mass measurements of the isobars {sup 211}Fr, {sup 211}Po and {sup 211}Rn have clearly demonstrated the scientific potential of the MR-TOF-MS for the investigation of exotic nuclei and the power of the data analysis system. Difficult measurements with overlapping mass distributions with only a few counts in the measured spectra were the challenge for the new data analysis method based on the maximum likelihood method. The drifts during the measurements were corrected with the developed time-resolved calibration method. After the improvements of the setup as a consequence of

GEANT4 simulation and evaluation of a time-of-flight spectrometer for nuclear cross section measurements in particle therapy

International Nuclear Information System (INIS)

Gruenwald, Oxana

2011-01-01

In 2007 a new project has been launched in a cooperation between the RWTH Aachen Physics Department, the University Hospital Aachen and the Philips Research Laboratories. The project aim is to validate and improve GEANT4 nuclear interaction models for use in proton and ion therapy. The method chosen here is the measurement of nuclear reaction cross sections which will not only provide a comparison to the simulation but will also allow to improve some of the parameters in the nuclear models. In the first phase of the project 200 MeV protons are used as a projectile in combination with a thin graphite target. For use in particle therapy the excitation functions of the most frequently produced isotopes need to be measured with an accuracy of 10% or less. For this purpose a dedicated detector system has been designed and implemented in GEANT4. The detection of target fragments produced by protons in graphite is achieved via time-of-flight spectrometry. In the setup presented here the primary beam first hits the Start detector and initiates the time-of-flight measurement before it passes through the apertures of two Veto detectors and impinges on the target. Successively, the secondary particles emanating from the target travel a short distance of 70/80 cm through vacuum (0.1 mbar) before they hit one of the 20 Stop detectors which end the time-of-flight measurement and record the energy deposited by the particle. The dissertation at hand describes the underlying detector concept and presents a detailed GEANT4 simulation of the setup which allows to evaluate the detector performance with respect to target fragment identification at a projectile energy of 200 MeV. At first, correlations of time-of-flight and energy deposition are built from simulated data and are subsequently used to reconstruct mass spectra of the detected fragments. Such influences on the detection performance as the target thickness, the residual pressure within the detector chamber, the Veto system

GEANT4 simulation and evaluation of a time-of-flight spectrometer for nuclear cross section measurements in particle therapy

Energy Technology Data Exchange (ETDEWEB)

Gruenwald, Oxana

2011-06-08

In 2007 a new project has been launched in a cooperation between the RWTH Aachen Physics Department, the University Hospital Aachen and the Philips Research Laboratories. The project aim is to validate and improve GEANT4 nuclear interaction models for use in proton and ion therapy. The method chosen here is the measurement of nuclear reaction cross sections which will not only provide a comparison to the simulation but will also allow to improve some of the parameters in the nuclear models. In the first phase of the project 200 MeV protons are used as a projectile in combination with a thin graphite target. For use in particle therapy the excitation functions of the most frequently produced isotopes need to be measured with an accuracy of 10% or less. For this purpose a dedicated detector system has been designed and implemented in GEANT4. The detection of target fragments produced by protons in graphite is achieved via time-of-flight spectrometry. In the setup presented here the primary beam first hits the Start detector and initiates the time-of-flight measurement before it passes through the apertures of two Veto detectors and impinges on the target. Successively, the secondary particles emanating from the target travel a short distance of 70/80 cm through vacuum (0.1 mbar) before they hit one of the 20 Stop detectors which end the time-of-flight measurement and record the energy deposited by the particle. The dissertation at hand describes the underlying detector concept and presents a detailed GEANT4 simulation of the setup which allows to evaluate the detector performance with respect to target fragment identification at a projectile energy of 200 MeV. At first, correlations of time-of-flight and energy deposition are built from simulated data and are subsequently used to reconstruct mass spectra of the detected fragments. Such influences on the detection performance as the target thickness, the residual pressure within the detector chamber, the Veto system

Tag-elese or The Language of Tags

Directory of Open Access Journals (Sweden)

Jan Simons

2008-01-01

Full Text Available The core "meme" of Web 2.0 from which almost all other memes radiated was: 'You control your own data' (O'Reilly, 2005, 3. Key instruments for this user control are tagging systems that allow users to freely assign keywords of their own choosing to Internet resources of their own making as well as to documents produced by others. Of course, freely chosen keywords tags do not necessarily follow prefixed taxonomies or classification systems. But going by the maxim that interaction creates similarity and similarity creates interaction, the idea - or hope - is, however, that the tagging practices of individual users will eventually converge into an emergent common vocabulary or folksonomy (Merholz, 2004; Shirky, 2005; Vander Wal, 2005b; Mika, 2007. It is far from clear, however, that free tagging systems will eventually yield controlled vocabularies, and there are many incentives for idiosyncratic, ambiguous, and inconsistent uses of tags. Left to themselves, free tagging systems seem to be too wild and too chaotic for any order to emerge. But are these free tagging systems really as "feral" as they seem to be, or do they only look uncontrolled because one has been looking for order in the wrong place? I have done a quick-and-dirty" analysis of Flickr's tag cloud. The concept was: if folksonomies encourage users to tap on their own vernacular, everyday natural language must somehow "guide" the tagging practices of users of tagging systems. Flickr's tag cloud has been choosen because it may teach us something about tagging systems and folksonomies, and not - or not primarily - because of what tags may tell us about pictures.

LHCb: Optimization and Calibration of Flavour Tagging Algorithms for the LHCb experiment

CERN Multimedia

Falabella, A

2013-01-01

The LHCb purposes are to make precise measurements in $B$ and $D$ meson decays. In particular in time-dependent CP violation studies the determination of $B$ flavour at production ("Flavour Tagging") is fundamental. The performances and calibration of the flavour tagging algorithms with 2011 data collected by LHCb are reported. The performances of the flavour tagging algorithms on the relevant CP violation and asymmetry studies are also reported.

Extracting Tag Hierarchies

Science.gov (United States)

Tibély, Gergely; Pollner, Péter; Vicsek, Tamás; Palla, Gergely

2013-01-01

Tagging items with descriptive annotations or keywords is a very natural way to compress and highlight information about the properties of the given entity. Over the years several methods have been proposed for extracting a hierarchy between the tags for systems with a "flat", egalitarian organization of the tags, which is very common when the tags correspond to free words given by numerous independent people. Here we present a complete framework for automated tag hierarchy extraction based on tag occurrence statistics. Along with proposing new algorithms, we are also introducing different quality measures enabling the detailed comparison of competing approaches from different aspects. Furthermore, we set up a synthetic, computer generated benchmark providing a versatile tool for testing, with a couple of tunable parameters capable of generating a wide range of test beds. Beside the computer generated input we also use real data in our studies, including a biological example with a pre-defined hierarchy between the tags. The encouraging similarity between the pre-defined and reconstructed hierarchy, as well as the seemingly meaningful hierarchies obtained for other real systems indicate that tag hierarchy extraction is a very promising direction for further research with a great potential for practical applications. Tags have become very prevalent nowadays in various online platforms ranging from blogs through scientific publications to protein databases. Furthermore, tagging systems dedicated for voluntary tagging of photos, films, books, etc. with free words are also becoming popular. The emerging large collections of tags associated with different objects are often referred to as folksonomies, highlighting their collaborative origin and the “flat” organization of the tags opposed to traditional hierarchical categorization. Adding a tag hierarchy corresponding to a given folksonomy can very effectively help narrowing or broadening the scope of search

Extracting tag hierarchies.

Directory of Open Access Journals (Sweden)

Gergely Tibély

Full Text Available Tagging items with descriptive annotations or keywords is a very natural way to compress and highlight information about the properties of the given entity. Over the years several methods have been proposed for extracting a hierarchy between the tags for systems with a "flat", egalitarian organization of the tags, which is very common when the tags correspond to free words given by numerous independent people. Here we present a complete framework for automated tag hierarchy extraction based on tag occurrence statistics. Along with proposing new algorithms, we are also introducing different quality measures enabling the detailed comparison of competing approaches from different aspects. Furthermore, we set up a synthetic, computer generated benchmark providing a versatile tool for testing, with a couple of tunable parameters capable of generating a wide range of test beds. Beside the computer generated input we also use real data in our studies, including a biological example with a pre-defined hierarchy between the tags. The encouraging similarity between the pre-defined and reconstructed hierarchy, as well as the seemingly meaningful hierarchies obtained for other real systems indicate that tag hierarchy extraction is a very promising direction for further research with a great potential for practical applications. Tags have become very prevalent nowadays in various online platforms ranging from blogs through scientific publications to protein databases. Furthermore, tagging systems dedicated for voluntary tagging of photos, films, books, etc. with free words are also becoming popular. The emerging large collections of tags associated with different objects are often referred to as folksonomies, highlighting their collaborative origin and the "flat" organization of the tags opposed to traditional hierarchical categorization. Adding a tag hierarchy corresponding to a given folksonomy can very effectively help narrowing or broadening the scope of

Extracting tag hierarchies.

Science.gov (United States)

Tibély, Gergely; Pollner, Péter; Vicsek, Tamás; Palla, Gergely

2013-01-01

Tagging items with descriptive annotations or keywords is a very natural way to compress and highlight information about the properties of the given entity. Over the years several methods have been proposed for extracting a hierarchy between the tags for systems with a "flat", egalitarian organization of the tags, which is very common when the tags correspond to free words given by numerous independent people. Here we present a complete framework for automated tag hierarchy extraction based on tag occurrence statistics. Along with proposing new algorithms, we are also introducing different quality measures enabling the detailed comparison of competing approaches from different aspects. Furthermore, we set up a synthetic, computer generated benchmark providing a versatile tool for testing, with a couple of tunable parameters capable of generating a wide range of test beds. Beside the computer generated input we also use real data in our studies, including a biological example with a pre-defined hierarchy between the tags. The encouraging similarity between the pre-defined and reconstructed hierarchy, as well as the seemingly meaningful hierarchies obtained for other real systems indicate that tag hierarchy extraction is a very promising direction for further research with a great potential for practical applications. Tags have become very prevalent nowadays in various online platforms ranging from blogs through scientific publications to protein databases. Furthermore, tagging systems dedicated for voluntary tagging of photos, films, books, etc. with free words are also becoming popular. The emerging large collections of tags associated with different objects are often referred to as folksonomies, highlighting their collaborative origin and the "flat" organization of the tags opposed to traditional hierarchical categorization. Adding a tag hierarchy corresponding to a given folksonomy can very effectively help narrowing or broadening the scope of search. Moreover

TOFPET 2: A high-performance circuit for PET time-of-flight

Energy Technology Data Exchange (ETDEWEB)

Di Francesco, Agostino, E-mail: agodifra@lip.pt [LIP, Lisbon (Portugal); Bugalho, Ricardo [LIP, Lisbon (Portugal); PETsys Electronics, Oeiras (Portugal); Oliveira, Luis [CTS-UNINOVA, DEE FCT-UNL, Caparica (Portugal); Rivetti, Angelo [INFN - sez. Torino (Italy); Rolo, Manuel [LIP, Lisbon (Portugal); INFN - sez. Torino (Italy); Silva, Jose C.; Varela, Joao [LIP, Lisbon (Portugal); PETsys Electronics, Oeiras (Portugal)

2016-07-11

We present a readout and digitization ASIC featuring low-noise and low-power for time-of flight (TOF) applications using SiPMs. The circuit is designed in standard CMOS 110 nm technology, has 64 independent channels and is optimized for time-of-flight measurement in Positron Emission Tomography (TOF-PET). The input amplifier is a low impedance current conveyor based on a regulated common-gate topology. Each channel has quad-buffered analogue interpolation TDCs (time binning 20 ps) and charge integration ADCs with linear response at full scale (1500 pC). The signal amplitude can also be derived from the measurement of time-over-threshold (ToT). Simulation results show that for a single photo-electron signal with charge 200 (550) fC generated by a SiPM with (320 pF) capacitance the circuit has 24 (30) dB SNR, 75 (39) ps r.m.s. resolution, and 4 (8) mW power consumption. The event rate is 600 kHz per channel, with up to 2 MHz dark counts rejection.

Time- and energy resolved photoemission electron microscopy-imaging of photoelectron time-of-flight analysis by means of pulsed excitations

International Nuclear Information System (INIS)

Oelsner, Andreas; Rohmer, Martin; Schneider, Christian; Bayer, Daniela; Schoenhense, Gerd; Aeschlimann, Martin

2010-01-01

The present work enlightens the developments in time- and energy resolved photoemission electron microscopy over the past few years. We describe basic principles of the technique and demonstrate different applications. An energy- and time-filtering photoemission electron microscopy (PEEM) for real-time spectroscopic imaging can be realized either by a retarding field or hemispherical energy analyzer or by using time-of-flight optics with a delay line detector. The latter method has the advantage of no data loss at all as all randomly incoming particles are measured not only by position but also by time. This is of particular interest for pump-probe experiments in the femtosecond and attosecond time scale where space charge processes drastically limit the maximum number of photoemitted electrons per laser pulse. This work focuses particularly on time-of-flight analysis using a novel delay line detector. Time and energy resolved PEEM instruments with delay line detectors enable 4D imaging (x, y, Δt, E Kin ) on a true counting basis. This allows a broad range of applications from real-time observation of dynamic phenomena at surfaces to fs time-of-flight spectro-microscopy and even aberration correction. By now, these time-of-flight analysis instruments achieve intrinsic time resolutions of 108 ps absolute and 13.5 ps relative. Very high permanent measurement speeds of more than 4 million events per second in random detection regimes have been realized using a standard USB2.0 interface. By means of this performance, the time-resolved PEEM technique enables to display evolutions of spatially resolved (<25 nm) and temporal sliced images life on any modern computer. The method allows dynamics investigations of variable electrical, magnetic, and optical near fields at surfaces and great prospects in dynamical adaptive photoelectron optics. For dynamical processes in the ps time scale such as magnetic domain wall movements, the time resolution of the delay line detectors

Label-free measurement of the yeast short chain TAG lipase activity by ESI-MS after one-step esterification.

Science.gov (United States)

Ham, Hye Jin; Seo, Jongcheol; Yoon, Hye-Joo; Shin, Seung Koo

2017-03-01

Triacylglycerol (TAG) lipases hydrolyze ester bonds in TAG and release diacylglycerol (DAG), monoacylglycerol (MAG), and FA. We present a one-step chemical derivatization method for label-free quantification of a mixture of TAG, DAG, and MAG following lipase assay by ESI-MS. Because the ionization efficiencies of TAG, DAG, and MAG are not identical, lipase reaction products, DAG and MAG, are derivatized to TAG species by esterifying their hydroxyl groups using acyl chloride, whose acyl chain contains one less (or one more) -CH 2 group than that of substrate TAG. This resulted in three TAG species that were separated by 14 Da from one another and exhibited similar ion responses representing their molar amounts in the mass spectra. A good linear correlation was observed between peak intensity ratios and molar ratios in calibration curve. This method enables simultaneous quantification of TAG, DAG, and MAG in lipase assay and, in turn, allows stoichiometric determination of the concentrations of FAs released from TAG and DAG separately. By applying this strategy to measure both TAG and DAG lipolytic activities of the yeast Tgl2 lipase, we demonstrated its usefulness in studying enzymatic catalysis, as lipase enzymes often show dissimilar activities toward these lipids. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

Effect of the method of photomultiplier gain control on electron time-of-flight in FEhU-30

International Nuclear Information System (INIS)

Gladyshev, D.A.; Li, B.N.

1979-01-01

The effect of a method of control of the multiplication factor of a photomultiplier on the electron flight time has been investigated. Presented are the results of measuring the dependence of the electron flight time for the following methods of stabilizing the photomultiplier multiplication: adjustment of multiplication by changing the supply voltage; control of multiplication with the help of a resistor which shunts two neighbouring interdynode gaps, and the control of the multiplication factor by changing a magnetic field caused due to changes in the current flowing through a special solenoid. It has been found that in these methods changes in the flight time constituted 260 and 140 ns. Magnetic-field control does not affect the flight time with an accuracy of up to 20 ps

Crystal timing offset calibration method for time of flight PET scanners

Science.gov (United States)

Ye, Jinghan; Song, Xiyun

2016-03-01

In time-of-flight (TOF) positron emission tomography (PET), precise calibration of the timing offset of each crystal of a PET scanner is essential. Conventionally this calibration requires a specially designed tool just for this purpose. In this study a method that uses a planar source to measure the crystal timing offsets (CTO) is developed. The method uses list mode acquisitions of a planar source placed at multiple orientations inside the PET scanner field-of-view (FOV). The placement of the planar source in each acquisition is automatically figured out from the measured data, so that a fixture for exactly placing the source is not required. The expected coincidence time difference for each detected list mode event can be found from the planar source placement and the detector geometry. A deviation of the measured time difference from the expected one is due to CTO of the two crystals. The least squared solution of the CTO is found iteratively using the list mode events. The effectiveness of the crystal timing calibration method is evidenced using phantom images generated by placing back each list mode event into the image space with the timing offset applied to each event. The zigzagged outlines of the phantoms in the images become smooth after the crystal timing calibration is applied. In conclusion, a crystal timing calibration method is developed. The method uses multiple list mode acquisitions of a planar source to find the least squared solution of crystal timing offsets.

Novel time-of-flight spectrometer for the analysis of positron annihilation induced Auger electrons

International Nuclear Information System (INIS)

Hugenschmidt, Christoph; Legl, Stefan

2006-01-01

Positron annihilation induced Auger-electron spectroscopy (PAES) has several advantages over conventional Auger-electron spectroscopy such as extremely high surface sensitivity and outstanding signal-to-noise ratio at the Auger-transition energy. In order to benefit from these prominent features a low-energy positron beam of high intensity is required for surface sensitive PAES studies. In addition, an electron energy analyzer is required, which efficiently detects the Auger electrons with acceptable energy resolution. For this reason a novel time-of-flight (TOF) spectrometer has been developed at the intense positron source NEPOMUC that allows PAES studies within short measurement time. This TOF-PAES setup combines a trochoidal filter and a flight tube in a Faraday cage in order to achieve an improved energy resolution of about 1 eV at high electron energies up to E≅1000 eV. The electron flight time is the time between the annihilation radiation at the sample and when the electron hits a microchannel plate detector at the end of the flight tube

High precision mass measurements of thermalized relativistic uranium projectile and fission fragments with a multiple-reflection time-of-flight mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Ayet San Andres, Samuel [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Justus Liebig Universitaet, Giessen (Germany); Collaboration: FRS Ion Catcher-Collaboration

2016-07-01

At the FRS Ion Catcher at GSI, a relativistic beam of {sup 238}U at 1GeV/u was used to produce fission and projectile fragments on a beryllium target. The ions were separated in-flight at the FRS, thermalized in a cryogenic stopping cell and transferred to a multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) where high precision mass measurements were performed. The masses of several fission and projectile fragments were measured (including short-lived nuclei with half-lives down to 18 ms) and the possibility of tailoring an isomerically clean beam for other experiments was demonstrated. With the demonstrated performance of the MR-TOF-MS and the expected production rates of exotic nuclei far from stability at the next-generation facilities such as FAIR, novel mass measurements of nuclei close to the neutron drip line will be possible and key information for understanding the r-process will be available. The results from the last experiment and an outlook of possible future mass measurements close to the neutron drip line at FAIR with the MR-TOF-MS are presented.

Time of flight spectrometry in heavy ions backscattering analysis

International Nuclear Information System (INIS)

Chevarier, A.; Chevarier, N.

1983-05-01

Time of flight spectrometry for backscattering analysis of MeV heavy ions is proposed. The capabilities and limitations of this method are investigated. Depth and mass resolution obtained in measurements of oxide films thickness as well as in GaAs layers analysis are presented. The importance of minimizing pile-up without significant loss of resolution by use of an adequate absorber set just in front of the rear detector is underlined

Tunneling Flight Time, Chemistry, and Special Relativity.

Science.gov (United States)

Petersen, Jakob; Pollak, Eli

2017-09-07

Attosecond ionization experiments have not resolved the question "What is the tunneling time?". Different definitions of tunneling time lead to different results. Second, a zero tunneling time for a material particle suggests that the nonrelativistic theory includes speeds greater than the speed of light. Chemical reactions, occurring via tunneling, should then not be considered in terms of a nonrelativistic quantum theory calling into question quantum dynamics computations on tunneling reactions. To answer these questions, we define a new experimentally measurable paradigm, the tunneling flight time, and show that it vanishes for scattering through an Eckart or a square barrier, irrespective of barrier length or height, generalizing the Hartman effect. We explain why this result does not lead to experimental measurement of speeds greater than the speed of light. We show that this tunneling is an incoherent process by comparing a classical Wigner theory with exact quantum mechanical computations.

Effects of gauge volume on pseudo-strain induced in strain measurement using time-of-flight neutron diffraction

International Nuclear Information System (INIS)

Suzuki, Hiroshi; Harjo, Stefanus; Abe, Jun; Xu, Pingguang; Aizawa, Kazuya; Akita, Koichi

2013-01-01

Spurious or pseudo-strains observed in time-of-flight (TOF) neutron diffraction due to neutron attenuation, surface-effects and a strain distribution within the gauge volume were investigated. Experiments were carried out on annealed and bent ferritic steel bars to test these effects. The most representative position in the gauge volume corresponds to the neutron-weighted center of gravity (ncog), which takes into account variations in intensity within the gauge volume due to neutron attenuation and/or absence of material in the gauge volume. The average strain in the gauge volume was observed to be weighted towards the ncog position but following an increase in the size of the gauge volume the weighted average strain was changed because of the change in the ncog position when a strain gradient appeared within the gauge volume. On the other hand, typical pseudo-strains, which are well known, did appear in through-surface strain measurements when the gauge volume was incompletely filled by the sample. Tensile pseudo-strains due to the surface-effect increased near the sample surface and exhibited a similar trend regardless of the size of the gauge volume, while the pseudo-strains increased faster for the smaller gauge volume. Furthermore, a pseudo-strain due to a change in the ncog position was observed even when the gauge volume was perfectly filled in the sample, and it increased with an increase in the size of the gauge volume. These pseudo-strains measured were much larger than those simulated by the conventional modeling, whereas they were simulated by taking into account an incident neutron beam divergence additionally in the model. Therefore, the incident divergence of the incident neutron beam must be carefully designed to avoid pseudo-strains in time-of-flight neutron diffractometry

Calibration of the time response functions of a quenched plastic scintillator for neutron time of flight

CERN Document Server

Chen, J B; Peng, H S; Tang, C H; Zhang, B H; Ding, Y K; Chen, M; Chen, H S; Li, C G; Wen, T S; Yu, R Z

2002-01-01

The time response functions of an ultrafast quenched plastic scintillation detector used to measure neutron time of flight spectra were calibrated by utilizing cosmic rays and implosion neutrons from DT-filled capsules at the Shenguang II laser facility. These sources could be regarded as delta function pulses due to their much narrower time widths than those of the time response functions of the detection system. The results showed that the detector responses to DT neutrons and to cosmic rays were 1.18 and 0.96 ns FWHM, respectively.

Parameters’ Covariance in Neutron Time of Flight Analysis – Explicit Formulae

Energy Technology Data Exchange (ETDEWEB)

Odyniec, M. [NSTec; Blair, J. [NSTec

2014-12-01

We present here a method that estimates the parameters’ variance in a parametric model for neutron time of flight (NToF). The analytical formulae for parameter variances, obtained independently of calculation of parameter values from measured data, express the variances in terms of the choice, settings, and placement of the detector and the oscilloscope. Consequently, the method can serve as a tool in planning a measurement setup.

Proposed measurement of tagged deep inelastic scattering in Hall A of Jefferson lab

Energy Technology Data Exchange (ETDEWEB)

Montgomery, Rachel [Univ. of Glasgow, Scotland (United Kingdom); Annand, John [Univ. of Glasgow, Scotland (United Kingdom); Dutta, Dipangkar [Mississippi State Univ., Mississippi State, MS (United States); Keppel, Cynthia E. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); King, Paul [The Ohio State Univ., Columbus, OH (United States). Dept of Physics; Wojtsekhowski, Bogdan [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Jixie [Univ. of Virginia, Charlottesville, VA (United States)

2017-03-01

A tagged deep inelastic scattering (TDIS) experiment is planned for Hall A of Jefferson Lab, which will probe the mesonic content of the nucleon directly. Low momentum recoiling (and spectator) protons will be measured in coincidence with electrons scattered in a deep inelastic regime from hydrogen (and deuterium) targets, covering kinematics of 8 < W2 < 18 GeV2, 1 < Q2 < 3 (GeV/c)2 and 0:05 < x < 0:2. The tagging technique will help identify scattering from partons in the meson cloud and provide access to the pion structure function via the Sullivan process. The experiment will yield the first TDIS results in the valence regime, for both proton and neutron targets. We present here an overview of the experiment.

Time of flight spectroscopy with muonic hydrogen

International Nuclear Information System (INIS)

Marshall, G.M.; Bailey, J.M.; Beer, G.A.

1993-01-01

Time of flight techniques coupled with muonic deuterium and tritium atoms in vacuum can be used to measure parameters important in the understanding of muon catalyzed fusion interactions. Muonic deuterium atomic beams with energy of order 1 eV have been produced via transfer and emission from solid hydrogen containing small deuterium concentrations. Measurements of energy loss in pure deuterium are presented which test calculations of σ μd+D . Muonic tritium beams should be produced in a similar way, with an energy distribution which overlaps the predicted muonic molecular (dμt) formation resonances. The existence of resonances is crucial for high cycling rates in muon catalyzed fusion, but direct experimental verification of strengths and energies is not yet possible by other means. Results of simulations demonstrate how the resonance structure might be confirmed

Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y., E-mail: thuzhangyu@foxmail.com; Huang, S. L., E-mail: huangsling@tsinghua.edu.cn; Wang, S.; Zhao, W. [State Key Laboratory of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China)

2016-05-15

The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert–Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of <1% and thus can act as a universal time-of-flight extraction method for narrowband Lamb wave detection signals.

Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals

International Nuclear Information System (INIS)

Zhang, Y.; Huang, S. L.; Wang, S.; Zhao, W.

2016-01-01

The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert–Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of <1% and thus can act as a universal time-of-flight extraction method for narrowband Lamb wave detection signals.

LHCb: Optimization and Calibration of Flavour Tagging Algorithms for the LHCb experiment

CERN Multimedia

Falabella, A

2013-01-01

The LHCb purposes are to make precise measurements of $B$ and $D$ meson decays. In particular in time-dependent CP violation studies the determination of $B$ flavour at production is fundamental. This is known as "flavour tagging" and at LHCb it is performed with several algorithms. The performances and calibration of the flavour tagging algorithms with 2011 data collected by LHCb are reported. Also the performances of the flavour tagging algorithms in the relevant CP violation and asymmetry studies are also reported.

The Dubna double-arm time-of-flight spectrometer for heavy-ion reaction products

International Nuclear Information System (INIS)

Schilling, K.D.; Gippner, P.; Seidel, W.; Stary, F.; Will, E.; Heidel, K.; Lukyanov, S.M.; Penionzhkevich, Yu.E.; Salamatin, V.S.; Sodan, H.; Chubarian, G.G.

1986-05-01

The double-arm time-of-flight spectrometer DEMAS designed for the detection and identification of heavy-ion reaction products at incident energies below 10 MeV/amu is presented. Based on the kinematic coincidence method, the relevant physical information is obtained from the measurement of the two correlated velocity vectors of the binary fragments. Construction and performance of the different detector systems applied to measure the time-of-flight values, the position coordinates and the kinetic energies of both fragments are presented in detail. The description of the data acquisition and analysing procedures is followed by the discussion of some experimental examples to demonstrate the spectrometer performance. A mass resolution of typically 4 - 5 amu (fwhm) is routinely achieved. (author)

IceBridge Riegl Laser Altimeter L1B Time-Tagged Laser Ranges

Data.gov (United States)

National Aeronautics and Space Administration — The NASA IceBridge Riegl Laser Altimeter L1B Time-Tagged Laser Ranges (ILUTP1B) data set contains laser ranges, returned pulses, and deviation for returned pulses in...

Design and realization of a space-borne reflectron time of flight mass spectrometer: electronics and measuring head

International Nuclear Information System (INIS)

Devoto, P.

2006-03-01

The purpose of this thesis is the design of the electronics of a time of flight mass spectrometer, the making and the vacuum tests of a prototype which can be put onboard a satellite. A particular effort was necessary to decrease to the maximum the mass and electric consumption of the spectrometer, which led to the development of new circuits. The work completed during this thesis initially concerns the electronics of the measuring equipment which was conceived in a concern for modularity. A complete 'reflectron' type mass spectrometer was then designed, simulated and developed. The built prototype, which uses the developed electronics, was exposed to ion flows of different masses and energies in the CESR vacuum chambers. Its measured performances validate the implemented principles and show that an identical mass spectrometer can be put onboard a satellite with profit, for planetary or solar missions. (author)

IPNS time-of-flight single crystal diffractometer

International Nuclear Information System (INIS)

Schultz, A.J.; Teller, R.G.; Williams, J.M.

1983-01-01

The single crystal diffractometer (SCD) at the Argonne Intense Pulsed Neutron Source (IPNS) utilizes the time-of-flight (TOF) Laue technique to provide a three-dimensional sampling of reciprocal space during each pulse. The instrument contains a unique neutron position-sensitive 6 Li-glass scintillation detector with an active area of 30 x 30 cm. The three-dimensional nature of the data is very useful for fast, efficient measurement of Bragg intensities and for the studies of superlattice and diffuse scattering. The instrument was designed to achieve a resolution of 2% or better (R = δQ/Q) with 2 THETA > 60 0 and lambda > 0.7A

The ARGUS time-of-flight system

International Nuclear Information System (INIS)

Heller, R.; Klinger, T.; Salomon, R.; Schubert, K.R.; Stiewe, J.; Waldi, R.; Weseler, S.

1985-01-01

The time-of-flight system of the ARGUS detector at the DORIS e + e - storage ring consists of 64 barrel scintillation counters covering 75% of 4π, and 2x48 end cap counters, covering 17% of 4π. The barrel counters are viewed by two phototubes each, while the end cap counters have one tube only. The time-of-flight system serves as a part of the fast trigger and identifies charged particles. The time resolution achieved during the first year of ARGUS operation is 210 ps for Bhabhas (which are used for the off-line monitoring of the system), and 220 ps for hadrons, both in barrel and end cap counters. This converts into a three standard deviation mass separation up to 700 MeV/c between pions and kaons and 1200 MeV/c between kaons and protons. Electrons can be separated from heavier particles up to 230 MeV/c. (orig.)

Experimental investigations of micro-scale flow and heat transfer phenomena by using molecular tagging techniques

International Nuclear Information System (INIS)

Hu, Hui; Jin, Zheyan; Lum, Chee; Nocera, Daniel; Koochesfahani, Manoochehr

2010-01-01

Recent progress made in the development of novel molecule-based flow diagnostic techniques, including molecular tagging velocimetry (MTV) and lifetime-based molecular tagging thermometry (MTT), to achieve simultaneous measurements of multiple important flow variables for micro-flows and micro-scale heat transfer studies is reported in this study. The focus of the work described here is the particular class of molecular tagging tracers that relies on phosphorescence. Instead of using tiny particles, especially designed phosphorescent molecules, which can be turned into long-lasting glowing marks upon excitation by photons of appropriate wavelength, are used as tracers for both flow velocity and temperature measurements. A pulsed laser is used to 'tag' the tracer molecules in the regions of interest, and the tagged molecules are imaged at two successive times within the photoluminescence lifetime of the tracer molecules. The measured Lagrangian displacement of the tagged molecules provides the estimate of the fluid velocity. The simultaneous temperature measurement is achieved by taking advantage of the temperature dependence of phosphorescence lifetime, which is estimated from the intensity ratio of the tagged molecules in the acquired two phosphorescence images. The implementation and application of the molecular tagging approach for micro-scale thermal flow studies are demonstrated by two examples. The first example is to conduct simultaneous flow velocity and temperature measurements inside a microchannel to quantify the transient behavior of electroosmotic flow (EOF) to elucidate underlying physics associated with the effects of Joule heating on electrokinematically driven flows. The second example is to examine the time evolution of the unsteady heat transfer and phase changing process inside micro-sized, icing water droplets, which is pertinent to the ice formation and accretion processes as water droplets impinge onto cold wind turbine blades

Optical Time-of-Flight and Absorbance Imaging of Biologic Media

Science.gov (United States)

Benaron, David A.; Stevenson, David K.

1993-03-01

Imaging the interior of living bodies with light may assist in the diagnosis and treatment of a number of clinical problems, which include the early detection of tumors and hypoxic cerebral injury. An existing picosecond time-of-flight and absorbance (TOFA) optical system has been used to image a model biologic system and a rat. Model measurements confirmed TOFA principles in systems with a high degree of photon scattering; rat images, which were constructed from the variable time delays experienced by a fixed fraction of early-arriving transmitted photons, revealed identifiable internal structure. A combination of light-based quantitative measurement and TOFA localization may have applications in continuous, noninvasive monitoring for structural imaging and spatial chemometric analysis in humans.

Photon-tagged and B-meson-tagged b-jet production at the LHC

Directory of Open Access Journals (Sweden)

Jinrui Huang

2015-11-01

Full Text Available Tagged jet measurements in high energy hadronic and nuclear reactions provide constraints on the energy and parton flavor origin of the parton shower that recoils against the tagging particle. Such additional insight can be especially beneficial in illuminating the mechanisms of heavy flavor production in proton–proton collisions at the LHC and their modification in the heavy ion environment, which are not fully understood. With this motivation, we present theoretical results for isolated-photon-tagged and B-meson-tagged b-jet production at sNN=5.1 TeV for comparison to the upcoming lead–lead data. We find that photon-tagged b-jets exhibit smaller momentum imbalance shift in nuclear matter, and correspondingly smaller energy loss, than photon-tagged light flavor jets. Our results show that B-meson tagging is most effective in ensuring that the dominant fraction of recoiling jets originate from prompt b-quarks. Interestingly, in this channel the large suppression of the cross section is not accompanied by a significant momentum imbalance shift.

Time-frequency energy density precipitation method for time-of-flight extraction of narrowband Lamb wave detection signals.

Science.gov (United States)

Zhang, Y; Huang, S L; Wang, S; Zhao, W

2016-05-01

The time-of-flight of the Lamb wave provides an important basis for defect evaluation in metal plates and is the input signal for Lamb wave tomographic imaging. However, the time-of-flight can be difficult to acquire because of the Lamb wave dispersion characteristics. This work proposes a time-frequency energy density precipitation method to accurately extract the time-of-flight of narrowband Lamb wave detection signals in metal plates. In the proposed method, a discrete short-time Fourier transform is performed on the narrowband Lamb wave detection signals to obtain the corresponding discrete time-frequency energy density distribution. The energy density values at the center frequency for all discrete time points are then calculated by linear interpolation. Next, the time-domain energy density curve focused on that center frequency is precipitated by least squares fitting of the calculated energy density values. Finally, the peak times of the energy density curve obtained relative to the initial pulse signal are extracted as the time-of-flight for the narrowband Lamb wave detection signals. An experimental platform is established for time-of-flight extraction of narrowband Lamb wave detection signals, and sensitivity analysis of the proposed time-frequency energy density precipitation method is performed in terms of propagation distance, dispersion characteristics, center frequency, and plate thickness. For comparison, the widely used Hilbert-Huang transform method is also implemented for time-of-flight extraction. The results show that the time-frequency energy density precipitation method can accurately extract the time-of-flight with relative error of wave detection signals.

Real-Time Aerodynamic Parameter Estimation without Air Flow Angle Measurements

Science.gov (United States)

Morelli, Eugene A.

2010-01-01

A technique for estimating aerodynamic parameters in real time from flight data without air flow angle measurements is described and demonstrated. The method is applied to simulated F-16 data, and to flight data from a subscale jet transport aircraft. Modeling results obtained with the new approach using flight data without air flow angle measurements were compared to modeling results computed conventionally using flight data that included air flow angle measurements. Comparisons demonstrated that the new technique can provide accurate aerodynamic modeling results without air flow angle measurements, which are often difficult and expensive to obtain. Implications for efficient flight testing and flight safety are discussed.

Barrel time-of-flight detector for the PANDA experiment at FAIR

Science.gov (United States)

Gruber, L.; Brunner, S. E.; Marton, J.; Orth, H.; Suzuki, K.; PANDA Tof Group

2016-07-01

The barrel time-of-flight detector for the PANDA experiment at FAIR is foreseen as a Scintillator Tile (SciTil) Hodoscope based on several thousand small plastic scintillator tiles read-out with directly attached Silicon Photomultipliers (SiPMs). The main tasks of the system are an accurate determination of the time origin of particle tracks to avoid event mixing at high collision rates, relative time-of-flight measurements as well as particle identification in the low momentum regime. The main requirements are the use of a minimum material amount and a time resolution of σ < 100 ps. We have performed extensive optimization studies and prototype tests to prove the feasibility of the SciTil design and finalize the R&D phase. In a 2.7 GeV/c proton beam at Forschungszentrum Jülich a time resolution of about 80 ps has been achieved using SiPMs from KETEK and Hamamatsu with an active area of 3 × 3mm2. Employing the Digital Photon Counter from Philips a time resolution of about 30 ps has been reached.

The properties of tagged lattice fluids: II. Velocity correlation functions

International Nuclear Information System (INIS)

Binder, P.M.; d'Humieres, D.; Poujol, L.

1988-01-01

We report preliminary measurements of the velocity autocorrelation function for a tagged particle in a lattice gas. These measurements agree with the Boltzmann-level theory. The Green-Kubo integration of these measurements agrees with theoretical predictions for the diffusion coefficient. To within the error bars of the simulations (3 /times/ 10/sup /minus/3/) we observe no long-time tails. 9 refs., 1 fig., 1 tab

Radiation measurement of civil air flight

International Nuclear Information System (INIS)

Winter, M.

1999-01-01

In order to aquire knowledge of the radiation exposure of civil aircrew members in common flight altitudes, it was necessary to develop a practicable measurement system. Radiation exposure was hereby estimated by using the ACREM-System, which is patented by the Austrian Research Centres Seibersdorf (OEFZS). Total Equivalent Dose could be estimated in a simple way by combining a measured component of the radiation field in flight altitudes and the results of simulation with LUIN 94 particle transport code (Keran O'Brian). To verify the results of the measurement system, a tissue equivalent proportional counter (TEPC) was used. Because of the difficult measurement conditions in cargo airplanes, special attention had to be taken to make the measurement equipment easy to use and transport. Special software has been developed to automate the measurement and the evaluation of the large amount of collected data. Measurements in standard calibration photon fields for the characterization of the equipment could be performed at the Primary Dosimetry Laboratory for Austria at the Austrian Research Centre (OEFZS) in Seibersdorf. Additional measurements were performed at Physikalisch Technische Bundesanstalt Braunschweig (PTB, Germany) and Paul Scherer Institute (PSI, Switzerland) to determine the reponse of the instruments to high energy photon and standard neutron fields. (author)

Multi-Reflection Time-of-Flight Mass Separation and Spectrometry

CERN Document Server

Kreim, Susanne; Wolf, R N

2014-01-01

The mass of a nucleus is one of its most fundamental ground-state properties and reveals the strength of nuclear binding. Investigating the binding energy of nuclei with respect to the number of protons and neutrons in a nucleus is important for advancing nuclear theory and increases our understanding of nucleosynthesis in supernovae and neutron stars. Precision mass measurements on radioactive nuclides belong to the state-of-the-art techniques [1, 2]. Presently, four complementary techniques are applied: isochronous and Schottky mass spectrometry in storage rings (IMS and SMS, respectively), magnetic-rigidity time-of-flight (TOF-ρ) measurements, and Penning-trap mass spectrometry (PTMS). With measurement cycles in the sub-ms range, IMS and TOF-Bρ MS are well suited for very short-lived species while offering moderate relative precision on the level of 10−6. A higher precision is achieved by SMS but with the need for measurement times on the order of several seconds. As soon as masses with a relative prec...

Space Radiation Measurement on the Polar Route onboard the Korean Commercial Flights

Directory of Open Access Journals (Sweden)

Junga Hwang

2010-03-01

Full Text Available This study was performed by the policy research project of Ministry of Land, Transport and Maritime Affairs, which title is “Developing safety standards and management of space radiation on the polar route”. In this research, total six experiments were performed using Korean commercial flights (B747. Three of those are on the polar route and the other three are on the north pacific route. Space radiation exposure measured on the polar route is the average 84.7 uSv. The simulation result using CARI-6M program gives 84.9 uSv, which is very similar to measured value. For the departure flight using the north pacific route, the measured space radiation is the average 74.4 uSv. It seems that is not so different to use the polar route or not for the return flight because the higher latitude effect causing the increase of space radiation is compensated by the shortened flight time effect causing decreasing space radiation exposure.

Analysis of gait using a treadmill and a Time-of-flight camera

DEFF Research Database (Denmark)

Jensen, Rasmus Ramsbøl; Paulsen, Rasmus Reinhold; Larsen, Rasmus

2009-01-01

We present a system that analyzes human gait using a treadmill and a Time-of-flight camera. The camera provides spatial data with local intensity measures of the scene, and data are collected over several gait cycles. These data are then used to model and analyze the gait. For each frame...

Iodine Tagging Velocimetry in a Mach 10 Wake

Science.gov (United States)

Balla, Robert Jeffrey

2013-01-01

A variation on molecular tagging velocimetry (MTV) [1] designated iodine tagging velocimetry (ITV) is demonstrated. Molecular iodine is tagged by two-photon absorption using an Argon Fluoride (ArF) excimer laser. A single camera measures fluid displacement using atomic iodine emission at 206 nm. Two examples ofMTVfor cold-flowmeasurements areN2OMTV [2] and Femtosecond Laser Electronic Excitation Tagging [3]. These, like most MTV methods, are designed for atmospheric pressure applications. Neither can be implemented at the low pressures (0.1- 1 Torr) in typical hypersonic wakes. Of all the single-laser/singlecamera MTV approaches, only Nitric-Oxide Planar Laser Induced Fluorescence-based MTV [4] has been successfully demonstrated in a Mach 10 wake. Oxygen quenching limits transit times to 500 ns and accuracy to typically 30%. The present note describes the photophysics of the ITV method. Off-body velocimetry along a line is demonstrated in the aerothermodynamically important and experimentally challenging region of a hypersonic low-pressure near-wake in a Mach 10 air wind tunnel. Transit times up to 10 µs are demonstrated with conservative errors of 10%.

The use of external electronic tags on fish: an evaluation of tag retention and tagging effects

DEFF Research Database (Denmark)

Jepsen, Niels; Thorstad, Eva B.; Havn, Torgeir

2015-01-01

External tagging of fish with electronic tags has been used for decades for a wide range of marine and freshwater species. In the early years of fish telemetry research, it was the most commonly used attachment method, but later internal implants became preferred. Recently, the number of telemetry...... unsuitable for surgical implantation, or when using tags with sensors recording the external environment. The most commonly reported problems with external tags are tissue damage, premature tag loss, and decreased swimming capacity, but the effects are highly context dependent and species specific. Reduced......, but particularly there are few studies on predation risk, social interactions, and studies distinguishing capture and handling effects from tagging effects. For PSATs, especially those that are large relative to fish size, there are particular problems with a high proportion of premature tag losses, reduced...

Tempting To Tag: An Experimental Comparison Of Four Tagging Input Mechanisms

Directory of Open Access Journals (Sweden)

Mark Melenhorst

2010-01-01

Full Text Available Tagging helps achieve improved indexing and recommendation of resources (e.g., videos or pictures in large data collections. In order to reap the benefits of tagging, people must be persuaded to label the resources they consume. This paper reports on a study in which four different tagging input mechanisms and their effect on users' motivation to tag were compared. The mechanisms consisted of a standard tag input box, a chatbot-like environment, a bookmarking mechanism, and a "tag and vote" game. The results of our experiment show that the use of the nonstandard tagging input mechanisms does not affect users' motivation to tag. In some instances tagging mechanisms were found to distract users from their primary task: consuming resources. Persuading people to tag might be accomplished more effectively by using other motivating tagging mechanisms (e.g., tagging games, or motivation could be created by explaining the usefulness of tagging.

TOF-SEMSANS—Time-of-flight spin-echo modulated small-angle neutron scattering

NARCIS (Netherlands)

Strobl, M.; Tremsin, A.S.; Hilger, A.; Wieder, F.; Kardjilov, N.; Manke, I.; Bouwman, W.G.; Plomp, J.

2012-01-01

We report on measurements of spatial beam modulation of a polarized neutron beam induced by triangular precession regions in time-of-flight mode and the application of this novel technique spin-echo modulated small-angle neutron scattering (SEMSANS) to small-angle neutron scattering in the very

Deuterium-tritium neutron yield measurements with the 4.5 m neutron-time-of-flight detectors at NIF.

Science.gov (United States)

Moran, M J; Bond, E J; Clancy, T J; Eckart, M J; Khater, H Y; Glebov, V Yu

2012-10-01

The first several campaigns of laser fusion experiments at the National Ignition Facility (NIF) included a family of high-sensitivity scintillator∕photodetector neutron-time-of-flight (nTOF) detectors for measuring deuterium-deuterium (DD) and DT neutron yields. The detectors provided consistent neutron yield (Y(n)) measurements from below 10(9) (DD) to nearly 10(15) (DT). The detectors initially demonstrated detector-to-detector Y(n) precisions better than 5%, but lacked in situ absolute calibrations. Recent experiments at NIF now have provided in situ DT yield calibration data that establish the absolute sensitivity of the 4.5 m differential tissue harmonic imaging (DTHI) detector with an accuracy of ± 10% and precision of ± 1%. The 4.5 m nTOF calibration measurements also have helped to establish improved detector impulse response functions and data analysis methods, which have contributed to improving the accuracy of the Y(n) measurements. These advances have also helped to extend the usefulness of nTOF measurements of ion temperature and downscattered neutron ratio (neutron yield 10-12 MeV divided by yield 13-15 MeV) with other nTOF detectors.

Chern Numbers Hiding in Time of Flight Images

Science.gov (United States)

Satija, Indubala; Zhao, Erhai; Ghosh, Parag; Bray-Ali, Noah

2011-03-01

Since the experimental realization of synthetic magnetic fields in neural ultracold atoms, transport measurement such as quantized Hall conductivity remains an open challenge. Here we propose a novel and feasible scheme to measure the topological invariants, namely the chern numbers, in the time of flight images. We study both the commensurate and the incommensurate flux, with the later being the main focus here. The central concept underlying our proposal is the mapping between the chern numbers and the size of the dimerized states that emerge when the two-dimensional hopping is tuned to the highly anisotropic limit. In a uncoupled double quantum Hall system exhibiting time reversal invariance, only odd-sized dimer correlation functions are non-zero and hence encode quantized spin current. Finally, we illustrate that inspite of highly fragmented spectrum, a finite set of chern numbers are meaningful. Our results are supported by direct numerical computation of transverse conductivity. NBA acknowledges support from a National Research Council postdoctoral research associateship.

Time-of-flight detector with KBr working medium

International Nuclear Information System (INIS)

Arvanov, A.N.; Gavalyan, V.G.; Lorikyan, M.P.

1983-01-01

A detector of controlled secondary electron emission as a 3-electrode focusing electrostatic system of the photomultiplier input chamber having a microchannel electron plate herringbone assembly with the total gain of approXimately 10 7 is described. A controlled secondary emission emitter based on MgO or KBr is installed as a cathode. The detector is designed for time-of-flight spectrometers. The time resolution is < or approximately equal to 0.5 ns. The time-of-flight system realized on the base of such two detectors has 100% detection efficiency and it is ''transparent'' for an identified particle. Its characteristics for α particle, deuteron and proton detection are estimated

Calculation of the flux attenuation and multiple scattering correction factors in time of flight technique for double differential cross section measurements

International Nuclear Information System (INIS)

Martin, G.; Coca, M.; Capote, R.

1996-01-01

Using Monte Carlo method technique , a computer code which simulates the time of flight experiment to measure double differential cross section was developed. The correction factor for flux attenuation and multiple scattering, that make a deformation to the measured spectrum, were calculated. The energy dependence of the correction factor was determined and a comparison with other works is shown. Calculations for Fe 56 at two different scattering angles were made. We also reproduce the experiment performed at the Nuclear Analysis Laboratory for C 12 at 25 celsius degree and the calculated correction factor for the is measured is shown. We found a linear relation between the scatter size and the correction factor for flux attenuation

Assessing and minimizing contamination in time of flight based validation data

Science.gov (United States)

Lennox, Kristin P.; Rosenfield, Paul; Blair, Brenton; Kaplan, Alan; Ruz, Jaime; Glenn, Andrew; Wurtz, Ronald

2017-10-01

Time of flight experiments are the gold standard method for generating labeled training and testing data for the neutron/gamma pulse shape discrimination problem. As the popularity of supervised classification methods increases in this field, there will also be increasing reliance on time of flight data for algorithm development and evaluation. However, time of flight experiments are subject to various sources of contamination that lead to neutron and gamma pulses being mislabeled. Such labeling errors have a detrimental effect on classification algorithm training and testing, and should therefore be minimized. This paper presents a method for identifying minimally contaminated data sets from time of flight experiments and estimating the residual contamination rate. This method leverages statistical models describing neutron and gamma travel time distributions and is easily implemented using existing statistical software. The method produces a set of optimal intervals that balance the trade-off between interval size and nuisance particle contamination, and its use is demonstrated on a time of flight data set for Cf-252. The particular properties of the optimal intervals for the demonstration data are explored in detail.

The ANTARES recoil time-of-flight spectrometer

Energy Technology Data Exchange (ETDEWEB)

Martin, J.W.; Russell, G.J. [New South Wales Univ., Kensington, NSW (Australia); Cohen, D.D.; Dytlewski, N. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1996-12-31

The Australian National Tandem for Applied Research (ANTARES), is a 8MV FN tandem particle accelerator at the Australian Nuclear Science and Technology Organisation. Research on the accelerator is divided between two groups, Accelerator Mass Spectrometry (AMS) and lon Beam Analysis (IBA). The IBA group carries out a range of research projects from nuclear physics to materials characterisation. The major IBA project on the accelerator is a recoil time-of-flight spectrometer which consists of two electrostatic time pulse generators and an ion-implanted surface barrier detector. The spectrometer is ideally suited to the profiling of layered multi-element materials, and has been used to characterise materials such as metal-germanides, optoelectronics, superconductors and catalytic converters. This paper will describe the time-of-flight system as well as some recent materials characterisation results. 1 refs., 3 figs.

The ANTARES recoil time-of-flight spectrometer

Energy Technology Data Exchange (ETDEWEB)

Martin, J W; Russell, G J [New South Wales Univ., Kensington, NSW (Australia); Cohen, D D; Dytlewski, N [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1997-12-31

The Australian National Tandem for Applied Research (ANTARES), is a 8MV FN tandem particle accelerator at the Australian Nuclear Science and Technology Organisation. Research on the accelerator is divided between two groups, Accelerator Mass Spectrometry (AMS) and lon Beam Analysis (IBA). The IBA group carries out a range of research projects from nuclear physics to materials characterisation. The major IBA project on the accelerator is a recoil time-of-flight spectrometer which consists of two electrostatic time pulse generators and an ion-implanted surface barrier detector. The spectrometer is ideally suited to the profiling of layered multi-element materials, and has been used to characterise materials such as metal-germanides, optoelectronics, superconductors and catalytic converters. This paper will describe the time-of-flight system as well as some recent materials characterisation results. 1 refs., 3 figs.

The electro-mechanical integration of the NA62 GigaTracker time tagging pixel detector

CERN Document Server

Morel, M; Aglieri Rinella, G; Carassiti, V; Ceccucci, A; Daguin, J; Fiorini, M; Jarron, P; Kaplon, J; Mapelli, A; Marchetto, F; Noy, M; Nuessle, G; Perktold, L; Petagna, P; Riedler, P

2010-01-01

The NA62 GigaTracker is a low mass time tagging hybrid pixel detector operating in a beam with a particle rate of 750 MHz. It consists of three stations with a sensor size of 60 × 27mm2 containing 18000 pixels, each 300 × 300μm2. The active area is connected to a matrix of 2 × 5 pixel ASICs, which time tag the arrival of the particles with a binning of 100 ps. The detector operates in vacuum at -20 to 0°C and the material budget per station must be below 0.5% X0. Due to the high radiation environment of 2 × 1014 1 MeV neutron equivalent cm−2/yr−1 it is planned to exchange the detector modules regularly. The low material budget, cooling requirements and the request for easy module access has driven the electro-mechanical integration of the GigaTracker, which is presented in this paper

Flavour tagging performance in LHCb

International Nuclear Information System (INIS)

Grabalosa Gandara, Marc

2009-01-01

To do precise CP violation measurements, the best possible determination of the flavour of the B-meson is necessary. This report summarizes the flavour tagging performances for the LHCb experiment. The flavour tagging is obtained through a combination of several methods, based on different signatures. The use of control channels, which are decays to flavour-specific final states, will allow to determine the wrong tag fraction ω (the probability of a tag to be wrong), which can be used as an input for the determination of CKM unitarity triangle angles.

Comparison of a simulated velocity profile of a turbulent boundary layer with measurements obtained by Femtosecond Laser Electronic Excitation Tagging (FLEET)

Science.gov (United States)

New-Tolley, Matthew; Zhang, Yibin; Shneider, Mikhail; Miles, Richard

2017-11-01

Accurate velocimetry measurements of turbulent flows are essential for improving our understanding of turbulent phenomena and validating numerical approaches. Femtosecond Laser Electronic Excitation Tagging (FLEET) is an unseeded molecular tagging method for velocimetry measurements in flows which contain nitrogen. A femtosecond laser pulse is used to ionize and dissociate nitrogen molecules within its focal zone. The decaying plasma fluoresces in the visible and infrared spectrum over a period of microseconds which allows the displacement of the tagged region to be photographed to determine velocity. This study compares the experimental and numerical advection of the tagged region in a turbulent boundary layer generated by a supersonic flow over a flat plate. The tagged region in the simulation is approximated as an infinitely thin cylinder while the flow field is generated using the steady state boundary layer equations with an algebraic turbulence model. This approximation is justified by previous computational analyses, using an unsteady three-dimensional Navier-Stokes solver, which indicate that the radial perturbations of the tagged region are negligible compared to its translation. This research was conducted with government support from the Air Force Office of Scientific Research under Dr. Ivett Leyva and the Army Research Office under Dr. Matthew Munson.

Seasonal and circadian biases in bird tracking with solar GPS-tags.

Directory of Open Access Journals (Sweden)

Rafa Silva

Full Text Available Global Positioning System (GPS tags are nowadays widely used in wildlife tracking. This geolocation technique can suffer from fix loss biases due to poor satellite GPS geometry, that result in tracking data gaps leading to wrong research conclusions. In addition, new solar-powered GPS tags deployed on birds can suffer from a new "battery drain bias" currently ignored in movement ecology analyses. We use a GPS tracking dataset of bearded vultures (Gypaetus barbatus, tracked for several years with solar GPS tags, to evaluate the causes and triggers of fix and data retrieval loss biases. We compare two models of solar GPS tags using different data retrieval systems (Argos vs GSM-GPRS, and programmed with different duty cycles. Neither of the models was able to accomplish the duty cycle programed initially. Fix and data retrieval loss rates were always greater than expected, and showed non-random gaps in GPS locations. Number of fixes per month of tracking was a bad criterion to identify tags with smaller biases. Fix-loss rates were four times higher due to battery drain than due to poor GPS satellite geometry. Both tag models were biased due to the uneven solar energy available for the recharge of the tag throughout the annual cycle, resulting in greater fix-loss rates in winter compared to summer. In addition, we suggest that the bias found along the diurnal cycle is linked to a complex three-factor interaction of bird flight behavior, topography and fix interval. More fixes were lost when vultures were perching compared to flying, in rugged versus flat topography. But long fix-intervals caused greater loss of fixes in dynamic (flying versus static situations (perching. To conclude, we emphasize the importance of evaluating fix-loss bias in current tracking projects, and deploying GPS tags that allow remote duty cycle updates so that the most appropriate fix and data retrieval intervals can be selected.

Combination of same-side with opposite-side flavour tagging

CERN Document Server

Calvo, M; Musy, M

2010-01-01

A considerable number of CP violation measurements require the most possible accurate knowledge of the flavour at production of the reconstructed $B$ meson. The performance of different flavour tagging methods will be measured from control channels. One of the possible tagging methods that can be used is the one known as $Same Side kaon$. In this note we present how to calibrate the response of the tagging algorithms using the data and combine the result with the so called $Opposite Side tagging$. Also trigger and selection effects are briefly discussed.

Force measurements of flexible tandem wings in hovering and forward flights

International Nuclear Information System (INIS)

Zheng, Yingying; Wu, Yanhua; Tang, Hui

2015-01-01

Aerodynamic forces, power consumptions and efficiencies of flexible and rigid tandem wings undergoing combined plunging/pitching motion were measured in a hovering flight and two forward flights with Strouhal numbers of 0.6 and 0.3. Three flexible dragonfly-like tandem wing models termed Wing I, Wing II, and Wing III which are progressively less flexible, as well as a pair of rigid wings as the reference were operated at three phase differences of 0°, 90° and 180°. The results showed that both the flexibility and phase difference have significant effects on the aerodynamic performances. In both hovering and forward flights at a higher oscillation frequency of 1 Hz (St = 0.6), the Wing III model outperformed the other wing models with larger total horizontal force coefficient and efficiency. In forward flight at the lower frequency of 0.5 Hz (St = 0.3), Wing III, rigid wings and Wing II models performed best at 0°, 90° and 180° phase difference, respectively. From the time histories of force coefficients of fore- and hind-wings, different peak values, phase lags, and secondary peaks were found to be the important reasons to cause the differences in the average horizontal force coefficients. Particle image velocimetry and deformation measurements were performed to provide the insights into how the flexibility affects the aerodynamic performance of the tandem wings. The spanwise bending deformation was found to contribute to the horizontal force, by offering a more beneficial position to make LEV more attached to the wing model in both hovering and forward flights, and inducing a higher-velocity region in forward flight. (paper)

The advantages of orthogonal acceleration in ICP time-of-flight mass spectrometry

International Nuclear Information System (INIS)

Gaal, Andrew

2004-01-01

The OptiMass 8000 incorporates an orthogonal acceleration time-of-flight mass spectrometer. A general schematic of the instrument is given. The continuous ion beam is chopped by an orthogonal accelerator. A push out pulse supply is coupled to the accelerator for providing repetitive push-out voltages at a frequency of 30 kHz. The ion packets that are sliced out of the beam then travel within the field free space towards the SMARTGATE ion blanker. Orthogonal accelerator parameters are set to enable temporal-spatial focusing at the SMARTGATE ion blanker, so that iso-mass ion packets are resolved in time. Any ion packets of unwanted specie are ejected from the direction of travel by supplying pulsed voltages onto the deflection plates of the SMARTGATE. The ions to be measured are let through SMARTGATE and travel further down the field free space, to enter the ion reflectron. The ion reflectron increases the resolution of the mass spectrometer by means of temporal-energy focussing. After reflection, the ions travel within the field free space towards the discrete-dynode detector. In comparison to other acceleration geometries used in elemental time-of-flight mass spectrometry the OptiMass 8000 orthogonal acceleration geometry ultimately leads to superior resolution. As the energy spread is about 3 orders of magnitude lower in the time-of-flight direction for an oaTOFMS in comparison to an on-axis system, aberration acquired in the initial stages of acceleration are much lower. As a result the orthogonal acceleration scheme provides superior resolution at the first spatial focus point and the detector. The orthogonal acceleration time-of-flight analyzer of the OptiMass 8000 is able to provide resolution of at least 1800 at mass 238. (author)

Experiments at the time-of-flight neutron spectrometer GNEIS in Gatchina

International Nuclear Information System (INIS)

Shcherbakov, O.A.

1990-01-01

A brief description of the Gatchina neutron time-of-flight spectrometer GNEIS at the 1 GeV proton synchrocyclotron and its main characteristics are given. Some results of the nuclear fission experiments and neutron cross section measurements are presented not only to illustrate the facility performance but to outline the basic directions of the researches as well. 28 refs.; 10 figs

Real-time flavor tagging selection in ATLAS

CERN Document Server

Sahinsoy, M; The ATLAS collaboration

2014-01-01

In high-energy physics experiments, online selection is crucial to reject most uninteresting collisions; in particular, b-jet selections, part of the ATLAS trigger strategy, are meant to select final states with heavy-flavor content. This is the only option to select fully hadronic final states containing b-jets, and is important to reject QCD light jets and maintain affordable trigger rates without raising jet energy thresholds. ATLAS operated b-jet triggers in both 2011 and 2012 data-taking campaigns and is now working to improve the performance of tagging algorithms for Run2. An overview of the ATLAS b-jet trigger strategy and its performance on real data is presented in this contribution, along with future prospects. Data-driven techniques to extract the online b-tagging performance, a key ingredient for all analyses relying on such triggers, are also discussed and results presented.

Time-of-flight position-sensitive x-ray detection

International Nuclear Information System (INIS)

Mowat, J.W.

1981-01-01

A new method for recording beam-foil time-of-flight data is described. A stationary, side-window, position-senstive proportional counter, oriented with anode wire parallel to the ion beam, views the decay in flight of excited ions through a Soller slit x-ray collimator. In contrast to the standard method, the exciter foil, placed within or upstream from the field of view, is not moved during the acquisition of a decay curve. Each point on the anode acts like an independent detector seeing a unique segment of the ion beam. The correspondence between the downstream distance at which an ion decays and the position along the anode at which the x-ray is detected makes a pulse-height spectrum of position pulses equivalent to a time-of-flight decay curve. Thus an entire decay curve can now be acquired without moving the foil. Increased efficiency is the most significant improvement over the standard method in which the radiation detector views only a small segment of the flight path at any one time. Experiments using translating foils are subject to a spurious dependence of x-ray intensity on foil position if the foil is non-uniform (or non-uniformly aged) and wobbles as it moves. This effect is eliminated here. Foil aging effects which influence excitation rates and introduce a slowly varying time dependence of the x-ray intensity are automatically normalized by this multichannel technique. The application of this method to metastable x-ray emitting states of low-Z ions are discussed

Flavour Tagging developments within the LHCb experiment

CERN Document Server

Grabalosa, Marc

Flavour Tagging at the LHCb experiment is a fundamental tool for the measurement of B oscillations and the study of CP violation. This document explains the development of different tagging techniques and the different strategies used to combine them to determine the flavour of the B meson as precisely as possible. The response of the tagging algorithms also needs to be optimized and calibrated. Both procedures are described using the available LHCb datasets corresponding to various integrated luminosities. First results on the tagging performances are shown for different control channels and physics measurements.

Graph based techniques for tag cloud generation

DEFF Research Database (Denmark)

Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

2013-01-01

Tag cloud is one of the navigation aids for exploring documents. Tag cloud also link documents through the user defined terms. We explore various graph based techniques to improve the tag cloud generation. Moreover, we introduce relevance measures based on underlying data such as ratings...... or citation counts for improved measurement of relevance of tag clouds. We show, that on the given data sets, our approach outperforms the state of the art baseline methods with respect to such relevance by 41 % on Movielens dataset and by 11 % on Bibsonomy data set....

3.56-bits/cm Compact Inkjet Printed and Application Specific Chipless RFID Tag

KAUST Repository

Khan, Munawar M.

2015-10-26

© 2002-2011 IEEE. In this letter, a 28.5-bit chipless RFID tag, based on paper substrate and realized using inkjet printing technique is presented. Operating within ultrawideband, the tag occupies a compact size of 2 × 4 cm2. Focusing on applications requiring time and date identification, a novel encoding technique is presented that allows efficient frequency band allocation based on the number of required instances of time and date variables. A figure of merit (FOM) relating coding capacity and tag dimensions coined as code density is also introduced. A systematic design process followed by simulations and verified through measurements reveal a high code density of 3.56 bits/cm2 for the presented chipless tag.

Precision measurements with the multi-reflection time-of-flight mass spectrometer of ISOLTRAP at ISOLDE/CERN

Energy Technology Data Exchange (ETDEWEB)

Atanasov, Dinko; Ascher, Pauline; Borgmann, Christopher; Boehm, Christine; Eliseev, Sergey; Eronen, Tommi; George, Sebastian; Kisler, Dmitry; Naimi, Sarah [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Beck, Dietrich; Herfurth, Frank; Litvinov, Yuri; Minaya Ramirez, Enrique; Neidherr, Dennis [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Breitenfeldt, Martin [Instituut voor Kern- en Stralingsfysica, Celestijnenlaan 200d - bus 2418, 3001 Heverlee (Belgium); Cakirli, Burcu [University of Istanbul, Department of Physics, 34134 Istanbul (Turkey); Cocolios, Thomas Elias [University of Manchester, Manchester (United Kingdom); Herlert, Alexander Josef [FAIR GmbH, Planckstr. 1, D-64291 Darmstadt (Germany); Kowalska, Magdalena [CERN, Geneva 23, 1211 Geneva (Switzerland); Kreim, Susanne [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); CERN, Geneva 23, 1211 Geneva (Switzerland); Lunney, David; Manea, Vladimir [CSNSM-IN2P3-CNRS, 91405 Orsay Campus, Bat. 104, 108 (France); Rosenbusch, Marco; Schweikhard, Lutz; Wienholtz, Frank; Wolf, Robert [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, Felix-Hausdorff-Str. 6, 17487 Greifswald (Germany); Stanja, Juliane; Zuber, Kai [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, 01069 Dresden (Germany)

2014-07-01

The masses of exotic nuclides are among the most important input parameters for modern nuclear theory and astrophysical models. At the high-precision Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN, a multi-reflection time-of-flight mass spectrometer (MR-ToF-MS) in combination with a Bradbury-Nielsen gate (BNG) can be used to achieve high-resolution isobar purification with mass-resolving powers of 105 in a few tens of milliseconds. Furthermore, the MR-ToF device can be used as a spectrometer to determine the masses of nuclides with very low yields and short half-lives, where a Penning-trap mass measurement becomes impractical due to the lower transport efficiency and decay losses during the purification and measurement cycles. Recent cross-check experiments show that the MR-ToF MS allows mass measurements with uncertainties in the sub-ppm range. In a first application the mass measurements of the nuclides 53,54Ca was performed, delivered with production rates as low as 10/s and half-lives of only 90(6) ms. The nuclides serve as important benchmarks for testing modern chiral effective theory with realistic 3-body forces. The contribution presents the on-line mass spectrometer ISOLTRAP focusing on the new applications, which became possible after the implementation of the MR-ToF MS into the current setup. In particular, the mass measurements of the neutron-rich calcium isotopes up to A=54 are discussed. In addition, measurements of the isotonic potassium isotopes are reported.

Development of a geometry-compensated neutron time-of-flight detector for ICF applications with approximately 200 ps time response

International Nuclear Information System (INIS)

Murphy, T.J.; Lerche, R.A.

1992-01-01

Current-mode neutron time-of-flight detectors are used on Nova for neutron yield, ion temperature, and neutron emission time measurements. Currently used detectors are limited by the time response of the microchannel plate photomultiplier tubes used with the scintillators, scintillator decay time, scintillator thickness, and oscilloscope response time. A change in the geometry of the scintillator allows one to take advantage of the increased time resolution made possible by more advanced transient recorders and microchannel plate photomultiplier tubes. A prototype detector has been designed to incorporate these changes, and could potentially yield time resolution of less than 150 ps. Experimental results are presented demonstrating an ion temperature measurement of a direct-drive DT implosion on Nova

Rules for Flight Paths and Time of Flight for Flows in Porous Media with Heterogeneous Permeability and Porosity

Directory of Open Access Journals (Sweden)

Lihua Zuo

2017-01-01

Full Text Available Porous media like hydrocarbon reservoirs may be composed of a wide variety of rocks with different porosity and permeability. Our study shows in algorithms and in synthetic numerical simulations that the flow pattern of any particular porous medium, assuming constant fluid properties and standardized boundary and initial conditions, is not affected by any spatial porosity changes but will vary only according to spatial permeability changes. In contrast, the time of flight along the streamline will be affected by both the permeability and porosity, albeit in opposite directions. A theoretical framework is presented with evidence from flow visualizations. A series of strategically chosen streamline simulations, including systematic spatial variations of porosity and permeability, visualizes the respective effects on the flight path and time of flight. Two practical rules are formulated. Rule  1 states that an increase in permeability decreases the time of flight, whereas an increase in porosity increases the time of flight. Rule  2 states that the permeability uniquely controls the flight path of fluid flow in porous media; local porosity variations do not affect the streamline path. The two rules are essential for understanding fluid transport mechanisms, and their rigorous validation therefore is merited.

Real-time monitoring of Lévy flights in a single quantum system

Science.gov (United States)

Issler, M.; Höller, J.; Imamoǧlu, A.

2016-02-01

Lévy flights are random walks where the dynamics is dominated by rare events. Even though they have been studied in vastly different physical systems, their observation in a single quantum system has remained elusive. Here we analyze a periodically driven open central spin system and demonstrate theoretically that the dynamics of the spin environment exhibits Lévy flights. For the particular realization in a single-electron charged quantum dot driven by periodic resonant laser pulses, we use Monte Carlo simulations to confirm that the long waiting times between successive nuclear spin-flip events are governed by a power-law distribution; the corresponding exponent η =-3 /2 can be directly measured in real time by observing the waiting time distribution of successive photon emission events. Remarkably, the dominant intrinsic limitation of the scheme arising from nuclear quadrupole coupling can be minimized by adjusting the magnetic field or by implementing spin echo.

Proton Transfer Time-of-Flight Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Watson, Thomas B. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-03-01

The Proton Transfer Reaction Mass Spectrometer (PTRMS) measures gas-phase compounds in ambient air and headspace samples before using chemical ionization to produce positively charged molecules, which are detected with a time-of-flight (TOF) mass spectrometer. This ionization method uses a gentle proton transfer reaction method between the molecule of interest and protonated water, or hydronium ion (H₃O⁺), to produce limited fragmentation of the parent molecule. The ions produced are primarily positively charged with the mass of the parent ion, plus an additional proton. Ion concentration is determined by adding the number of ions counted at the molecular ion’s mass-to-charge ratio to the number of air molecules in the reaction chamber, which can be identified according to the pressure levels in the reaction chamber. The PTRMS allows many volatile organic compounds in ambient air to be detected at levels from 10–100 parts per trillion by volume (pptv). The response time is 1 to 10 seconds.

Analysis of rocket flight stability based on optical image measurement

Science.gov (United States)

Cui, Shuhua; Liu, Junhu; Shen, Si; Wang, Min; Liu, Jun

2018-02-01

Based on the abundant optical image measurement data from the optical measurement information, this paper puts forward the method of evaluating the rocket flight stability performance by using the measurement data of the characteristics of the carrier rocket in imaging. On the basis of the method of measuring the characteristics of the carrier rocket, the attitude parameters of the rocket body in the coordinate system are calculated by using the measurements data of multiple high-speed television sets, and then the parameters are transferred to the rocket body attack angle and it is assessed whether the rocket has a good flight stability flying with a small attack angle. The measurement method and the mathematical algorithm steps through the data processing test, where you can intuitively observe the rocket flight stability state, and also can visually identify the guidance system or failure analysis.

Real-time flavor tagging selection in ATLAS

CERN Document Server

Madaffari, D; The ATLAS collaboration

2014-01-01

In high-energy physics experiments on hadron colliders, online selection is crucial to reject most uninteresting collisions. In particular, the ATLAS experiment includes b-jet selections in its trigger strategy, in order to select final states with heavy-flavor content and enlarge its physics potentials. Dedicated selections are developed to quickly identify fully hadronic final states containing b-jets, while rejecting light QCD jets, and maintain affordable trigger rates without raising jet energy thresholds. ATLAS successfully operated b-jet trigger selections during both 2011 and 2012 data-taking campaigns and hard work is on-going now to improve the performance of tagging algorithms for coming Run2 in 2015. An overview of the ATLAS b-jet trigger strategy and its performance on real data is presented in this contribution, along with future prospects. Data-driven techniques to extract the online b-tagging performance, a key ingredient for all analyses relying on such triggers, are also discussed and result...

W/Top/Higgs-tagging in ATLAS

CERN Document Server

Norjoharuddeen, Nurfikri; The ATLAS collaboration

2017-01-01

We present updates of W, Top and Higgs tagging studies with the ATLAS detector. The performance of 2 variable taggers, HEPTopTagger and shower deconstruction are compared in Monte Carlo simulations. To asses the modelling of the taggers’ performance, the tagging efficiencies are measured, with the full 2015+2016 dataset, in semi-leptonic top quark pair events and the background rejections are measured in dijet and photon+jet topologies. Recent developments in subjet reconstruction techniques for high transverse momentum Higgs->bb tagging are also presented.

Guidance concepts for time-based flight operations

Science.gov (United States)

Vicroy, Dan D.

1990-01-01

Airport congestion and the associated delays are severe in today's airspace system and are expected to increase. NASA and the FAA is investigating various methods of alleviating this problem through new technology and operational procedures. One concept for improving airspace productivity is time-based control of aircraft. Research to date has focused primarily on the development of time-based flight management systems and Air Traffic Control operational procedures. Flight operations may, however, require special onboard guidance in order to satisfy the Air Traffic Control imposed time constraints. The results are presented of a simulation study aimed at evaluating several time-based guidance concepts in terms of tracking performance, pilot workload, and subjective preference. The guidance concepts tested varied in complexity from simple digital time-error feedback to an advanced time-referenced-energy guidance scheme.

Direct measurement of A$_{b}$ and A$_{c}$ at the Z$^{0}$ pole using a lepton tag

CERN Document Server

Abe, K; Adam, I; Akagi, T; Allen, N J; Arodzero, A; Ash, William W; Aston, D; Baird, K G; Baltay, C; Band, H R; Barakat, M B; Bardon, O; Barklow, Timothy L; Bashindzhagian, G L; Bauer, J M; Bellodi, G; Ben-David, R; Benvenuti, Alberto C; Bilei, G M; Bisello, D; Blaylock, G; Bogart, J R; Bolen, B D; Bower, G R; Brau, J E; Breidenbach, M; Bugg, W M; Burke, D; Burnett, T H; Burrows, P N; Byrne, R M; Calcaterra, A; Calloway, D H; Camanzi, B; Carpinelli, M; Cassell, R; Castaldi, R; Castro, A; Cavalli-Sforza, M; Chou, A; Church, E; Cohn, H O; Coller, J A; Covery, M R; Cook, V; Cotton, R; Cowan, R F; Coyne, D G; Crawford, G; Damerell, C J S; Danielson, M N; Daoudi, M; De Groot, N; Dell'Orso, R; Dervan, P J; De Sangro, R; Dima, M; de Oliveira, A; Dong, D N; Doser, Michael; Dubois, R; Eisenstein, B I; Eschenburg, V; Etzion, E; Fahey, S; Falciai, D; Fan, C; Fernández, J P; Fero, M J; Flood, K; Frey, R; Gillman, T; Gladding, G; González, S; Goodman, E R; Hart, E L; Harton, J L; Hasan, A; Hasuko, K; Hedges, S J; Hertzbach, S S; Hildreth, M D; Huber, J; Huffer, M E; Hughes, E W; Huynh, X; Hwang, H; Iwasaki, M; Jackson, D J; Jacques, P; Jaros, J A; Jiang, Z Y; Johnson, A S; Johnson, J R; Johnson, R A; Junk, T R; Kajikawa, R; Kalelkar, M S; Kamyshkov, Yu A; Kang, H J; Karliner, I; Kawahara, H; Kim, Y D; King, R; King, M E; Kofler, R R; Krishna, N M; Kroeger, R S; Langston, M; Lath, A; Leith, D W G S; Lia, V; Lin, C J S; Liu, X; Liu, M X; Loreti, M; Lu, A; Lynch, H L; Ma, J; Mahjouri, M; Mancinelli, G; Manly, S L; Mantovani, G C; Markiewicz, T W; Maruyama, T; Masuda, H; Mazzucato, E; McKemey, A K; Meadows, B T; Menegatti, G; Messner, R; Mockett, P M; Moffeit, K C; Moore, T B; Morii, M; Müller, D; Murzin, V S; Nagamine, T; Narita, S; Nauenberg, U; Neal, H; Nussbaum, M; Oishi, N; Onoprienko, D V; Osborne, L S; Panvini, R S; Park, H; Park, C H; Pavel, T J; Peruzzi, I; Piccolo, M; Piemontese, L; Pieroni, E; Pitts, K T; Plano, R J; Prepost, R; Prescott, C Y; Punkar, G D; Quigley, J; Ratcliff, B N; Reeves, T W; Reidy, J; Reinertsen, P L; Rensing, P E; Rochester, L S; Rowson, P C; Russell, J J; Saxton, O H; Schalk, T L; Schindler, R H; Schumm, B A; Schwiening, J; Sen, S; Serbo, V V; Shaevitz, M H; Shank, J T; Shapiro, G; Sherden, D J; Shmakov, K D; Simopoulos, C; Sinev, N B; Smith, S R; Smy, M B; Snyder, J A; Stängle, H; Stahl, A; Stamer, P E; Steiner, R; Steiner, H; Strauss, M G; Su, D; Suekane, F; Sugiyama, A; Suzuki, S; Swartz, M; Szumilo, A; Takahashi, T; Taylor, F E; Thom, J; Torrence, E; Toumbas, N K; Usher, T; Vannini, C; Vagvra, J; Vella, E N; Venuti, J P; Verdier, R; Verdini, P G; Wagner, S R; Wagner, D L; Waite, A P; Walston, S; Wang, J; Ward, C P; Watts, S J; Weidemann, A W; Weiss, E R; Whitaker, J S; White, S L; Wickens, F J; Williams, B; Williams, D C; Williams, S H; Willocq, S; Wilson, R J; Wisniewski, W J; Wittlin, J L; Woods, M; Word, G B; Wright, T R; Wyss, J; Yamamoto, R K; Yamartino, J M; Yang, X; Yashima, J; Yellin, S J; Young, C C; Yuta, H; Zapalac, G H; Zdarko, R W; Zhou, J

1999-01-01

The parity violation parameters A/sub b/ and A/sub c/ of the Zbb and Zcc couplings have been measured directly, using the polar angle dependence of the Z/sup 0/-pole polarized cross sections. Bottom and charmed hadrons were tagged via semileptonic decays. Both the muon and electron identification algorithms take advantage of new multivariate techniques, incorporating for the first time information from the SLD Cerenkov ring imaging detector. Based on the 1993-1995 SLD sample of 150000 Z/sup 0/ decays produced with highly polarized electron beams, we measure A/sub b/=0.910+or-0.068(stat)+or- 0.037(syst), A/sub c /=0.642+or-0.110(stat)+or-0.063(syst). (20 refs).

Time-of-flight measurements of heavy ions using Si PIN diodes

Energy Technology Data Exchange (ETDEWEB)

Strekalovsky, A. O., E-mail: alex.strek@bk.ru; Kamanin, D. V. [Joint Institute for Nuclear Research (Russian Federation); Pyatkov, Yu. V. [National Nuclear Research University MEPhI (Moscow Engineering Physics Institute) (Russian Federation); Kondratyev, N. A.; Zhuchko, V. E. [Joint Institute for Nuclear Research (Russian Federation); Ilić, S. [University of Novi Sad (Serbia); Alexandrov, A. A.; Alexandrova, I. A. [Joint Institute for Nuclear Research (Russian Federation); Jacobs, N. [University of Stellenbosch, Faculty of Military Science, Military Academy (South Africa); Kuznetsova, E. A.; Mishinsky, G. V.; Strekalovsky, O. V. [Joint Institute for Nuclear Research (Russian Federation)

2016-12-15

A new off-line timing method for PIN diode signals is presented which allows the plasma delay effect to be suppressed. Velocities of heavy ions measured by the new method are in good agreement within a wide range of masses and energies with velocities measured by time stamp detectors based on microchannel plates.

Study of a prototype module of a precision time-of-flight detector for particle identification at low momentum

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00388630

In this thesis, Time Of internally Reflected Cherenkov light detector (TORCH), proposed for the LHCb Upgrade to perform three-sigma separation between kaon and pion up to 10$\\ \\rm{GeV}/\\textit{c}$, was studied. TORCH is designed to add significant particle identification capability to the existing LHCb system based on two gas Ring Imaging Cherenkov detectors. TORCH would be placed at $\\sim$ 10 m from the interaction point, where the flight time difference between a primary pion and kaon is 37.5 ps. TORCH will give a pion-kaon separation of three sigma at 10$\\ \\rm{GeV}/\\textit{c}$ from the flight time using the Cherenkov photons generated by the charged particle in a 1 cm-thick quartz plate. In order to calculate accurately the flight time in a busy LHCb environment, Cherenkov angle and photon detection time information, as well as the momentum information from the tracking detector are included in the analysis. For the required TORCH performance, the flight time difference must be measured with a resolution o...

A suite of standard post-tagging evaluation metrics can help assess tag retention for field-based fish telemetry research

Science.gov (United States)

Gerber, Kayla M.; Mather, Martha E.; Smith, Joseph M.

2017-01-01

Telemetry can inform many scientific and research questions if a context exists for integrating individual studies into the larger body of literature. Creating cumulative distributions of post-tagging evaluation metrics would allow individual researchers to relate their telemetry data to other studies. Widespread reporting of standard metrics is a precursor to the calculation of benchmarks for these distributions (e.g., mean, SD, 95% CI). Here we illustrate five types of standard post-tagging evaluation metrics using acoustically tagged Blue Catfish (Ictalurus furcatus) released into a Kansas reservoir. These metrics included: (1) percent of tagged fish detected overall, (2) percent of tagged fish detected daily using abacus plot data, (3) average number of (and percent of available) receiver sites visited, (4) date of last movement between receiver sites (and percent of tagged fish moving during that time period), and (5) number (and percent) of fish that egressed through exit gates. These metrics were calculated for one to three time periods: early (of the study (5 months). Over three-quarters of our tagged fish were detected early (85%) and at the end (85%) of the study. Using abacus plot data, all tagged fish (100%) were detected at least one day and 96% were detected for > 5 days early in the study. On average, tagged Blue Catfish visited 9 (50%) and 13 (72%) of 18 within-reservoir receivers early and at the end of the study, respectively. At the end of the study, 73% of all tagged fish were detected moving between receivers. Creating statistical benchmarks for individual metrics can provide useful reference points. In addition, combining multiple metrics can inform ecology and research design. Consequently, individual researchers and the field of telemetry research can benefit from widespread, detailed, and standard reporting of post-tagging detection metrics.

Studies and comparisons of two photon-tagging systems for the production of monochromatic photon beams for photonuclear experiments

International Nuclear Information System (INIS)

Aniel, Thierry.

1982-06-01

The performance of photon beams obtained by two different tagging processes (tagging of ''hard'' annihilation photons with ''soft'' associated photons, tagging of bremstrahlung photons with associated electrons) on the same facility was studied. The two processes are described and experimental results on the characteristics of the resulting beams given. The respective advantages of both methods are compared with one another and with those of a quasi-monochromatic beam obtained by the in-flight annihilation of a positron beam. A development based on the second process is then studied together with its applications to photonuclear physics [fr

Development of time-of-flight RBS system using multi microchannel plates

International Nuclear Information System (INIS)

Nguyen, N.V.; Abo, S.; Lohner, T.; Sawaragi, H.; Wakaya, F.; Takai, M.

2007-01-01

A new time-of-flight Rutherford backscattering spectroscopy (TOF-RBS) system with two circular microchannel plates (MCPs) installed at a distance of 140 mm from a sample holder and a scattering angle of 125 o and a 100 kV focused ion beam column having a liquid metal ion source (LMIS) of AuSiBe alloy has been assembled to obtain high counting rate and enhanced mass resolution. The possible influence of the two MCPs by logical summation of the output signals on the time resolution was investigated by measuring dedicated thin deposited metallic samples. And, the time resolution was found in the range of 1.5-2 ns

Development of the STEFF detector for the neutron Time Of Flight facility (n_TOF), CERN

CERN Document Server

AUTHOR|(CDS)2092031

Signicant work has been performed on the development of STEFF (SpecTrometer for Exotic Fission Fragments), a 2E2V (2-Energy 2-Velocity) spectrometer built by the University of Manchester Fission Group. The majority of this work was in the development of the time-of-flight systems, in particular the stop detector; with the main goals of improving the timing resolution and the detection eciency of the ssion fragments. Further development of the STEFF spectrometer was done to enable 2E2V measurements of the $^{235}$U(n,f) reaction with coincident measurements using a white neutron spectra of energies ranging from 10 meV to 200 MeV provided by the n_TOF (neutron Time Of Flight) facility, CERN. The STEFF spectrometer was successfully operated twice on the Experimental Area-2 high flux pulsed neutron beam line resulting in 2E2V measurements for ssion events with neutron energies ranging from 20 meV to 10 MeV. The first experiment received 1.36 X 10$^{18}$ POT (Protons On Target) with stable conditions and the seco...

Ion optics of a time-of-flight mass spectrometer with electrostatic sector analyzers

International Nuclear Information System (INIS)

Sakurai, T.; Ito, H.; Matsuo, T.

1995-01-01

The ion optics for a high resolution time-of-flight mass spectrometer with electrostatic sector analyzers have been investigated. The multiple focusing (triple isochronous focusing and triple spacial focusing) conditions can be achieved by using a symmetrical arrangement of the sectors in a mass spectrometer. Both high mass resolution and high ion transmission can be accomplished simultaneously. The principles of MS/MS and MS/MS/MS analyses using a TOF mass spectrometer with electrostatic sector analyzers have been proposed. Product ion spectra can be obtained by measuring the total flight times and the kinetic energy of the products without any additional separation processes, any coincidence techniques or any special timing circuits. In an experiment, MS/MS and MS/MS/MS mass spectra have been obtained. The first generation product ions have been produced by a metastable decay, and the second generation products have been produced by a sequential decay. (orig.)

Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans.

Science.gov (United States)

Kang, Ji-Yeon; Kwon, Ohsuk; Gil, Jin Young; Oh, Doo-Byoung

2016-05-15

Mannose-6-phosphate (M-6-P) glycan analysis is important for quality control of therapeutic enzymes for lysosomal storage diseases. Here, we found that the analysis of glycans containing two M-6-Ps was highly affected by the hydrophilicity of the elution solvent used in high-performance liquid chromatography (HPLC). In addition, the performances of three fluorescent tags--2-aminobenzoic acid (2-AA), 2-aminobenzamide (2-AB), and 3-(acetyl-amino)-6-aminoacridine (AA-Ac)--were compared with each other for M-6-P glycan analysis using HPLC and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The best performance for analyzing M-6-P glycans was shown by 2-AA labeling in both analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

Gas Time-of-Flight Cherenkov Detector with Radiofrequency Phototube for FP420

International Nuclear Information System (INIS)

Margaryan, A.

2011-01-01

In this paper, the gas Cherenkov detector with radiofrequency phototube is considered as a fast-timing detector for FP420 project. The detector serves for precise Time-of-Flight measurements of forward going protons, capable of accurate vertex reconstruction and background rejection at high luminosities. The proposed technique is a high resolution (∼ 5 ps FWHM for a single proton), high rate (∼ MHz) and highly stable (less than 1 ps) timing technique capable to detect up to several tens events in a short (∼ 1 ns) time interval. (author)

Tempting to Tag : An Experimental Comparison of Four Tagging Input Mechanisms

OpenAIRE

Melenhorst, Mark; van Velsen, Lex

2010-01-01

Tagging helps achieve improved indexing and recommendation of resources (e.g., videos or pictures) in large data collections. In order to reap the benefits of tagging, people must be persuaded to label the resources they consume. This paper reports on a study in which four different tagging input mechanisms and their effect on users' motivation to tag were compared. The mechanisms consisted of a standard tag input box, a chatbot-like environment, a bookmarking mechanism, and a "tag and v...

A suite of standard post-tagging evaluation metrics can help assess tag retention for field-based fish telemetry research

Science.gov (United States)

Gerber, Kayla M.; Mather, Martha E.; Smith, Joseph M.

2017-01-01

Telemetry can inform many scientific and research questions if a context exists for integrating individual studies into the larger body of literature. Creating cumulative distributions of post-tagging evaluation metrics would allow individual researchers to relate their telemetry data to other studies. Widespread reporting of standard metrics is a precursor to the calculation of benchmarks for these distributions (e.g., mean, SD, 95% CI). Here we illustrate five types of standard post-tagging evaluation metrics using acoustically tagged Blue Catfish (Ictalurus furcatus) released into a Kansas reservoir. These metrics included: (1) percent of tagged fish detected overall, (2) percent of tagged fish detected daily using abacus plot data, (3) average number of (and percent of available) receiver sites visited, (4) date of last movement between receiver sites (and percent of tagged fish moving during that time period), and (5) number (and percent) of fish that egressed through exit gates. These metrics were calculated for one to three time periods: early ( 5 days early in the study. On average, tagged Blue Catfish visited 9 (50%) and 13 (72%) of 18 within-reservoir receivers early and at the end of the study, respectively. At the end of the study, 73% of all tagged fish were detected moving between receivers. Creating statistical benchmarks for individual metrics can provide useful reference points. In addition, combining multiple metrics can inform ecology and research design. Consequently, individual researchers and the field of telemetry research can benefit from widespread, detailed, and standard reporting of post-tagging detection metrics.

Digitizing data acquisition and time-of-flight pulse processing for ToF-ERDA

Energy Technology Data Exchange (ETDEWEB)

Julin, Jaakko, E-mail: jaakko.julin@jyu.fi; Sajavaara, Timo

2016-01-01

A versatile system to capture and analyze signals from multi channel plate (MCP) based time-of-flight detectors and ionization based energy detectors such as silicon diodes and gas ionization chambers (GIC) is introduced. The system is based on commercial digitizers and custom software. It forms a part of a ToF-ERDA spectrometer, which has to be able to detect recoil atoms of many different species and energies. Compared to the currently used analogue electronics the digitizing system provides comparable time-of-flight resolution and improved hydrogen detection efficiency, while allowing the operation of the spectrometer be studied and optimized after the measurement. The hardware, data acquisition software and digital pulse processing algorithms to suit this application are described in detail.

Neutron xyz - polarization analysis at a time-of-flight instrument

Energy Technology Data Exchange (ETDEWEB)

Ehlers, Georg [ORNL; Stewart, John Ross [ISIS Facility, Rutherford Appleton Laboratory; Andersen, Ken [ESS

2015-01-01

When implementing a dedicated polarization analysis setup at a neutron time-of-flight instrument with a large area detector, one faces enormous challenges. Nevertheless, significant progress has been made towards this goal over the last few years. This paper addresses systematic limitations of the traditional method that is used to make these measurements, and a possible strategy to overcome these limitations. This will be important, for diffraction as well as inelastic experiments, where the scattering occurs mostly out-of-plane.

Measurement of D-meson tagged jets in pp collisions at $\\sqrt{s}=7$~TeV with ALICE

CERN Document Server

Aiola, Salvatore

2017-04-25

We present the current status of the measurement of jets that contain a D meson (D-tagged jets) with ALICE. D-meson candidates, identified via their hadronic decay channels, were combined with the other charged tracks reconstructed with the central tracking system, using the anti-$k_{\\rm T}$ jet-finding algorithm. The yield of D-tagged jets was extracted through an invariant mass analysis of the D-meson candidates. A Monte Carlo simulation was used to determine the detector performance and validate the signal extraction techniques.

Determination of absorption changes from moments of distributions of times of flight of photons: optimization of measurement conditions for a two-layered tissue model.

Science.gov (United States)

Liebert, Adam; Wabnitz, Heidrun; Elster, Clemens

2012-05-01

Time-resolved near-infrared spectroscopy allows for depth-selective determination of absorption changes in the adult human head that facilitates separation between cerebral and extra-cerebral responses to brain activation. The aim of the present work is to analyze which combinations of moments of measured distributions of times of flight (DTOF) of photons and source-detector separations are optimal for the reconstruction of absorption changes in a two-layered tissue model corresponding to extra- and intra-cerebral compartments. To this end we calculated the standard deviations of the derived absorption changes in both layers by considering photon noise and a linear relation between the absorption changes and the DTOF moments. The results show that the standard deviation of the absorption change in the deeper (superficial) layer increases (decreases) with the thickness of the superficial layer. It is confirmed that for the deeper layer the use of higher moments, in particular the variance of the DTOF, leads to an improvement. For example, when measurements at four different source-detector separations between 8 and 35 mm are available and a realistic thickness of the upper layer of 12 mm is assumed, the inclusion of the change in mean time of flight, in addition to the change in attenuation, leads to a reduction of the standard deviation of the absorption change in the deeper tissue layer by a factor of 2.5. A reduction by another 4% can be achieved by additionally including the change in variance.

Contribution of time-of-flight information to limited-angle positron tomography

International Nuclear Information System (INIS)

Macdonald, B.; Perez-Mendez, V.; Tam, K.C.

1981-10-01

Limited-angle emission tomography was investigated using a two-dimensional phantom to generate positron events simulating a camera with two opposed parallel position-sensitive detectors collecting data within a 90 0 cone. The data, backprojected onto lines passing through the phantom volume, is used with a matrix reconstruction method to provide two-dimensional images. Image quality was measured using the standard deviation of the reconstructions with respect to the original phantom. The application of Phillips-Twomey smoothing to the deconvolution matrices has substantially improved the original reconstructions, a factor of 1.9 in signal to noise ratio, giving S/N = 3.4 for a phantom having an average of 150 events/pixel. Using photon time-of-flight to restrict the reconstruction volume a further considerable improvement is made. When the time-of-flight limited the contributing volume to 4 lines out of 11 the improvement was another factor of 1.9 giving S/N = 6.0 for the same phantom. Comparable increases in signal to noise ratios are expected for three-dimensional reconstructions

Low energy RBS-channeling measurement system with the use of a time-of-flight scattered ion detector

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, Masataka; Kobayashi, Naoto; Hayashi, Nobuyuki [Electrotechnical Lab., Tsukuba, Ibaraki (Japan)

1996-07-01

We have developed a low energy Rutherford backscattering spectrometry-ion channeling measurement system for the analysis of thin films and solid surfaces with the use of several tens keV hydrogen ions and a time-of-flight particle energy spectrometer. For the detection of the scattered ions new TOF spectrometer has been developed, which consists of two micro-channel-plate detectors. The pulsing of the primary ion beam is not necessary for this type of TOF measurement, and it is possible to observe continues scattered ion beams. The dimension of whole system is very compact compared to the conventional RBS-channeling measurement system with the use of MeV He ions. The energy resolution, {delta} E/E, for 25 keV H{sup +} was 4.1%, which corresponds to the depth resolution of 4.8 nm for silicon. The depth resolution of our system is better than that of conventional RBS system with MeV helium ions and solid state detectors. We have demonstrated the ion channeling measurement by this system with 25 keV hydrogen ions. The system can be available well to the analysis of thin films and solid surfaces with the use of the ion channeling effect. The observation of the reaction between Fe and hydrogen terminated silicon surface was also demonstrated. (J.P.N.)

Time lens for high-resolution neutron time-of-flight spectrometers

International Nuclear Information System (INIS)

Baumann, K.; Gaehler, R.; Grigoriev, P.; Kats, E.I.

2005-01-01

We examine in analytic and numeric ways the imaging effects of temporal neutron lenses created by traveling magnetic fields. For fields of parabolic shape we derive the imaging equations, investigate the time magnification, the evolution of the phase-space element, the gain factor, and the effect of finite beam size. The main aberration effects are calculated numerically. The system is technologically feasible and should convert neutron time-of-flight instruments from pinhole to imaging configuration in time, thus enhancing intensity and/or time resolution. Further fields of application for high-resolution spectrometry may be opened

Real-time flavour tagging selection in ATLAS

CERN Document Server

Varni, Carlo; The ATLAS collaboration

2017-01-01

The ATLAS experiment includes a well-developed trigger system that allows a selection of events which are thought to be of interest, while achieving a high overall rejection against less interesting processes. An important part of the online event selection is the ability to distinguish between jets arising from heavy-flavour quarks (b- and c-jets) and light jets (jets from u-, d-, s- and gluon jets) in real-time. This is essential for many physics analysis that include processes with large jet multiplicity and b-quarks in the final state. An overview of the b-jet triggers with a description of the application and performance of the offline Multivariate (MV2) b-tagging algorithms at High Level Trigger (HLT) in Run 2 will be presented. During 2016 b-jet trigger menu and algorithms were adapted to use The Fast Tracker (FTK) system which will be commissioned in 2017. We will show initial expected performance of newly designed triggers and compare it with the existing HLT chains.

Time series analysis methods and applications for flight data

CERN Document Server

Zhang, Jianye

2017-01-01

This book focuses on different facets of flight data analysis, including the basic goals, methods, and implementation techniques. As mass flight data possesses the typical characteristics of time series, the time series analysis methods and their application for flight data have been illustrated from several aspects, such as data filtering, data extension, feature optimization, similarity search, trend monitoring, fault diagnosis, and parameter prediction, etc. An intelligent information-processing platform for flight data has been established to assist in aircraft condition monitoring, training evaluation and scientific maintenance. The book will serve as a reference resource for people working in aviation management and maintenance, as well as researchers and engineers in the fields of data analysis and data mining.

Intraindividual Variability in Basic Reaction Time Predicts Middle-Aged and Older Pilots’ Flight Simulator Performance

Science.gov (United States)

2013-01-01

Objectives. Intraindividual variability (IIV) is negatively associated with cognitive test performance and is positively associated with age and some neurological disorders. We aimed to extend these findings to a real-world task, flight simulator performance. We hypothesized that IIV predicts poorer initial flight performance and increased rate of decline in performance among middle-aged and older pilots. Method. Two-hundred and thirty-six pilots (40–69 years) completed annual assessments comprising a cognitive battery and two 75-min simulated flights in a flight simulator. Basic and complex IIV composite variables were created from measures of basic reaction time and shifting and divided attention tasks. Flight simulator performance was characterized by an overall summary score and scores on communication, emergencies, approach, and traffic avoidance components. Results. Although basic IIV did not predict rate of decline in flight performance, it had a negative association with initial performance for most flight measures. After taking into account processing speed, basic IIV explained an additional 8%–12% of the negative age effect on initial flight performance. Discussion. IIV plays an important role in real-world tasks and is another aspect of cognition that underlies age-related differences in cognitive performance. PMID:23052365

Intraindividual variability in basic reaction time predicts middle-aged and older pilots' flight simulator performance.

Science.gov (United States)

Kennedy, Quinn; Taylor, Joy; Heraldez, Daniel; Noda, Art; Lazzeroni, Laura C; Yesavage, Jerome

2013-07-01

Intraindividual variability (IIV) is negatively associated with cognitive test performance and is positively associated with age and some neurological disorders. We aimed to extend these findings to a real-world task, flight simulator performance. We hypothesized that IIV predicts poorer initial flight performance and increased rate of decline in performance among middle-aged and older pilots. Two-hundred and thirty-six pilots (40-69 years) completed annual assessments comprising a cognitive battery and two 75-min simulated flights in a flight simulator. Basic and complex IIV composite variables were created from measures of basic reaction time and shifting and divided attention tasks. Flight simulator performance was characterized by an overall summary score and scores on communication, emergencies, approach, and traffic avoidance components. Although basic IIV did not predict rate of decline in flight performance, it had a negative association with initial performance for most flight measures. After taking into account processing speed, basic IIV explained an additional 8%-12% of the negative age effect on initial flight performance. IIV plays an important role in real-world tasks and is another aspect of cognition that underlies age-related differences in cognitive performance.

Preliminary test results of a flight management algorithm for fuel conservative descents in a time based metered traffic environment. [flight tests of an algorithm to minimize fuel consumption of aircraft based on flight time