Search

Your search keyword '"Viou, C."' showing total 19 results
Start Over Author "Viou, C."
19 results on '"Viou, C."'

1. Pulsars with NenuFAR: backend and pipelines

Author

Bondonneau, L., Grießmeier, J. -M., Theureau, G., Cognard, I., Brionne, M., Kondratiev, V., Bilous, A., McKee, J. W., Zarka, P., Viou, C., Guillemot, L., Chen, S., Main, R., Pilia, M., Possenti, A., Serylak, M., Shaifullah, G., Tiburzi, C., Verbiest, J. P. W., Wu, Z., Wucknitz, O., Yerin, S., Briand, C., Cecconi, B., Corbel, S., Dallier, R., Loh, A., Martin, L., Girard, J. N., and Tasse, C.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Phenomenology, Physics - Instrumentation and Detectors
Abstract

NenuFAR (New extension in Nan\c{c}ay upgrading LoFAR) is a new radio telescope developed and built on the site of the Nan\c{c}ay Radio Observatory. It is designed to observe the largely unexplored frequency window from 10 to 85\,MHz, offering a high sensitivity across its full bandwidth. NenuFAR has started its "early science" operation in July 2019, with 58\% of its final collecting area being available. Pulsars are one of the major topics for the scientific exploitation of this frequency range and represent an important challenge in terms of instrumentation. Designing instrumentation at these frequencies is complicated by the need to compensate for the effects of both the interstellar medium and the ionosphere on the observed signal. Our real-time pipeline LUPPI (Low frequency Ultimate Pulsar Processing Instrumentation) is able to cope with a high data rate and to provide real-time coherent de-dispersion down to the lowest frequencies reached by NenuFAR (10\,MHz). The full backend functionality is described, as well as the main pulsar observing modes (folded, single-pulse, waveform, and dynamic spectrum). This instrumentation allowed us to detect 172 pulsars in our first targeted search below 85\,MHz, including 10 millisecond pulsars (6 of which detected for the first time below 100 MHz). We also present some of the "early science" results of NenuFAR on pulsars: a high frequency resolution mapping of PSR B1919$+$21's emission profile and a detailed observation of single-pulse sub-structures from PSR~B0809$+$74 down to 16\,MHz, the high rate of giant-pulse emission from the Crab pulsar detected at 68.7\,MHz (43 events/min), and the illustration of the very good timing performance of the instrumentation, allowing us to study dispersion measure variations in great detail., Comment: 13 pages, 14 figures, submitted to A&A

Published
2020
Full Text
View/download PDF

2. Design, operation and performance of the PAON4 prototype transit interferometer

Author

Ansari, R., Campagne, J. E, Charlet, D., Moniez, M., Pailler, C., Perdereau, O., Taurigna, M., Martin, J. M., Rigaud, F., Colom, P., Abbon, Ph., Magneville, Ch., Pezzani, J., Viou, C., Torchinsky, S. A., Huang, Q., and Zhang, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

PAON4 is an L-band (1250-1500 MHz) small interferometer operating in transit mode deployed at the Nan\c{c}ay observatory in France, designed as a prototype instrument for Intensity Mapping. It features four 5~meter diameter dishes in a compact triangular configuration, with a total geometric collecting area of $\sim75 \mathrm{m^2}$, and equipped with dual polarization receivers. A total of 36 visibilities are computed from the 8 independent RF signals by the software correlator over the full 250~MHz RF band. The array operates in transit mode, with the dishes pointed toward a fixed declination, while the sky drifts across the instrument. Sky maps for each frequency channel are then reconstructed by combining the time-dependent visibilities from the different baselines observed at different declinations. This paper presents an overview of the PAON4 instrument design and goals, as a prototype for dish arrays to map the Large Scale Structure in radio, using intensity mapping of the atomic hydrogen $21~\mathrm{cm}$ line. We operated PAON4 over several years and use data from observations in different periods to assess the array performance. We present preliminary analysis of a large fraction of this data and discuss crucial issues for this type of instrument, such as the calibration strategy, instrument response stability, and noise behaviour., Comment: 17 pages, 16 figures, accepted to MNRAS

Published
2019
Full Text
View/download PDF

3. 1977-2017: 40 years of decametric observations of Jupiter and the Sun with the Nancay Decameter Array

Author

Lamy, L., Zarka, P., Cecconi, B., Klein, L. -K., Masson, S., Denis, L., Coffre, A., and Viou, C.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

The Nancay Decameter Array (NDA) routinely observes low frequency (10-100 MHz) radio emissions of Jupiter and the Sun since 4 decades. The NDA observations, acquired with a variety of receivers with increasing performances, were the basis for numerous studies of jovian and solar radio emissions and now form a unique long-term database spanning >3 solar cycles and jovian revolutions. In addition, the NDA historically brought a fruitful support to space-based radio observatories of the heliosphere, to multi-wavelength analyses of solar activity and contributes to the development of space weather services. After having summarized the NDA characteristics, this article presents latest instrumental and database developments, some recent scientific results and perspectives for the next decade., Comment: Refereed article

Published
2017
Full Text
View/download PDF

4. Radio emission of extensive air shower at CODALEMA: Polarization of the radio emission along the v*B vector

Author

Riviere, Colas, Ardouin, D., Belletoile, A., Berat, C., Breton, D., Charrier, D., Chauvin, J., Chendeb, M., Cordier, A., Dagoret-Campagne, S., Dallier, R., Denis, L., Dumez-Viou, C., Fabrice, C., Garcon, T., Garrido, X., Gautherot, N., Gousset, T., Haddad, F., Koang, D. H., Lamblin, J., Lautridou, P., Lebrun, D., Lecacheux, A., Lefeuvre, F., Martin, L., Meyer, E., Meyer, F., Meyer-Vernet, N., Monnier-Ragaigne, D., Montanet, F., Payet, K., Plantier, G., Ravel, O., Revenu, B., Riviere, C., Saugrin, T., Sourice, A., Stassi, P., Stutz, A., and Valcares, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Cosmic rays extensive air showers (EAS) are associated with transient radio emission, which could provide an efficient new detection method of high energy cosmic rays, combining a calorimetric measurement with a high duty cycle. The CODALEMA experiment, installed at the Radio Observatory in Nancay, France, is investigating this phenomenon in the 10^17 eV region. One challenging point is the understanding of the radio emission mechanism. A first observation indicating a linear relation between the electric field produced and the cross product of the shower axis with the geomagnetic field direction has been presented (B. Revenu, this conference). We will present here other strong evidences for this linear relationship, and some hints on its physical origin., Comment: Contribution to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009. 4 pages, 8 figures. v2: Typo fixed, arxiv references added

Published
2009

5. Geomagnetic origin of the radio emission from cosmic ray induced air showers observed by CODALEMA

Author

Ardouin, D., Belletoile, A., Berat, C., Breton, D., Charrier, D., Chauvin, J., Chendeb, M., Cordier, A., Dagoret-Campagne, S., Dallier, R., Denis, L., Dumez-Viou, C., Fabrice, C., Garcon, T., Garrido, X., Gautherot, N., Gousset, T., Haddad, F., Koang, D. H., Lamblin, J., Lautridou, P., Lebrun, D., Lecacheux, A., Lefeuvre, F., Martin, L., Meyer, E., Meyer, F., Meyer-Vernet, N., Monnier-Ragaigne, D., Montanet, F., Payet, K., Plantier, G., Ravel, O., Revenu, B., Riviere, C., Saugrin, T., Sourice, A., Stassi, P., Stutz, A., and Valcares, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The new setup of the CODALEMA experiment installed at the Radio Observatory in Nancay, France, is described. It includes broadband active dipole antennas and an extended and upgraded particle detector array. The latter gives access to the air shower energy, allowing us to compute the efficiency of the radio array as a function of energy. We also observe a large asymmetry in counting rates between showers coming from the North and the South in spite of the symmetry of the detector. The observed asymmetry can be interpreted as a signature of the geomagnetic origin of the air shower radio emission. A simple linear dependence of the electric field with respect to vxB is used which reproduces the angular dependencies of the number of radio events and their electric polarity., Comment: 9 pages, 15 figures, 1 table

Published
2009
Full Text
View/download PDF

6. Pulsars with NenuFAR: Backend and pipelines

Author

Bondonneau, L, Griessmeier, J, Theureau, G, Cognard, I, Brionne, M, Kondratiev, V, Bilous, A, Mckee, J, Zarka, P, Viou, C, Guillemot, L, Chen, S, Main, R, Pilia, M, Possenti, A, Serylak, M, Shaifullah, G, Tiburzi, C, Verbiest, J, Wu, Z, Wucknitz, O, Yerin, S, Briand, C, Cecconi, B, Corbel, S, Dallier, R, Girard, J, Loh, A, Martin, L, Tagger, M, Tasse, C, Bondonneau L., Griessmeier J. -M., Theureau G., Cognard I., Brionne M., Kondratiev V., Bilous A., McKee J. W., Zarka P., Viou C., Guillemot L., Chen S., Main R., Pilia M., Possenti A., Serylak M., Shaifullah G., Tiburzi C., Verbiest J. P. W., Wu Z., Wucknitz O., Yerin S., Briand C., Cecconi B., Corbel S., Dallier R., Girard J. N., Loh A., Martin L., Tagger M., Tasse C., Bondonneau, L, Griessmeier, J, Theureau, G, Cognard, I, Brionne, M, Kondratiev, V, Bilous, A, Mckee, J, Zarka, P, Viou, C, Guillemot, L, Chen, S, Main, R, Pilia, M, Possenti, A, Serylak, M, Shaifullah, G, Tiburzi, C, Verbiest, J, Wu, Z, Wucknitz, O, Yerin, S, Briand, C, Cecconi, B, Corbel, S, Dallier, R, Girard, J, Loh, A, Martin, L, Tagger, M, Tasse, C, Bondonneau L., Griessmeier J. -M., Theureau G., Cognard I., Brionne M., Kondratiev V., Bilous A., McKee J. W., Zarka P., Viou C., Guillemot L., Chen S., Main R., Pilia M., Possenti A., Serylak M., Shaifullah G., Tiburzi C., Verbiest J. P. W., Wu Z., Wucknitz O., Yerin S., Briand C., Cecconi B., Corbel S., Dallier R., Girard J. N., Loh A., Martin L., Tagger M., and Tasse C.

Abstract

Context. NenuFAR (New extension in Nançay upgrading LOFAR) is a new radio telescope developed and built on the site of the Nançay Radio Observatory. It is designed to observe the largely unexplored frequency window from 10 to 85 MHz, offering a high sensitivity across its full bandwidth. NenuFAR has started its "early science"operation in July 2019, with 58% of its final collecting area. Aims. Pulsars are one of the major phenomena utilized in the scientific exploitation of this frequency range and represent an important challenge in terms of instrumentation. Designing instrumentation at these frequencies is complicated by the need to compensate for the effects of both the interstellar medium and the ionosphere on the observed signal. We have designed a dedicated backend and developed a complete pulsar observation and data analysis pipeline, which we describe in detail in the present paper, together with first science results illustrating the diversity of the pulsar observing modes. Methods. Our real-Time pipeline LUPPI (Low frequency Ultimate Pulsar Processing Instrumentation) is able to cope with a high data rate and provide real-Time coherent de-dispersion down to the lowest frequencies reached by NenuFAR (10 MHz). The full backend functionality is described, as the available pulsar observing modes (folded, single-pulse, waveform, and dynamic spectrum). Results. We also present some of the early science results of NenuFAR on pulsars: The detection of 12 millisecond pulsars (eight of which are detected for the first time below 100 MHz); a high-frequency resolution mapping of the PSR B1919+21 emission profile and a detailed observation of single-pulse substructures from PSR B0809+74 down to 16 MHz; the high rate of giant-pulse emission from the Crab pulsar detected at 68.7 MHz (43 events per minute); and the illustration of the very good timing performance of the instrumentation, which allows us to study dispersion measure variations in great detail.

Published
2021

7. Pulsars with NenuFAR: Backend and pipelines

Author

Bondonneau, L., primary, Grießmeier, J.-M., additional, Theureau, G., additional, Cognard, I., additional, Brionne, M., additional, Kondratiev, V., additional, Bilous, A., additional, McKee, J. W., additional, Zarka, P., additional, Viou, C., additional, Guillemot, L., additional, Chen, S., additional, Main, R., additional, Pilia, M., additional, Possenti, A., additional, Serylak, M., additional, Shaifullah, G., additional, Tiburzi, C., additional, Verbiest, J. P. W., additional, Wu, Z., additional, Wucknitz, O., additional, Yerin, S., additional, Briand, C., additional, Cecconi, B., additional, Corbel, S., additional, Dallier, R., additional, Girard, J. N., additional, Loh, A., additional, Martin, L., additional, Tagger, M., additional, and Tasse, C., additional

Published
2021
Full Text
View/download PDF

8. Design, operation and performance of the PAON4 prototype transit interferometer

Author

Ansari, R, primary, Campagne, J E, primary, Charlet, D, primary, Moniez, M, primary, Pailler, C, primary, Perdereau, O, primary, Taurigna, M, primary, Martin, J M, primary, Rigaud, F, primary, Colom, P, primary, Abbon, Ph, primary, Magneville, Ch, primary, Pezzani, J, primary, Viou, C, primary, Torchinsky, S A, primary, Huang, Q, primary, and Zhang, J, primary

Published
2020
Full Text
View/download PDF

9. Two RFI Mitigation Experiments With The Embrace Demonstrator

Author

Hellbourg, G., Dumez-Viou, C., Weber, R., Abed-Meraim, Karim, Taffoureau, C., Torchinsky, S., Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire pluridisciplinaire de recherche en ingénierie des systèmes, mécanique et énergétique (PRISME), Université d'Orléans (UO)-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), and Abed-Meraim, Karim

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

10. RFI Mitigation in Radio Astronomy: an Overview

Author

Weber, Rodolphe, Hellbourg, Gregory, Dumez-Viou, C., Boonstra, A.J., Torchinsky, S., Capdessus, Cécile, Abed-Meraim, Karim, Laboratoire Pluridisciplinaire de Recherche en Ingénierie des Systèmes, Mécanique et Energétique (PRISME), Université d'Orléans (UO)-Ecole Nationale Supérieure d'Ingénieurs de Bourges (ENSI Bourges), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Astronomische Rechen-Institut [Heidelberg] (ARI), Zentrum für Astronomie der Universität Heidelberg (ZAH), and Universität Heidelberg [Heidelberg]-Universität Heidelberg [Heidelberg]

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, ComputerApplications_COMPUTERSINOTHERSYSTEMS, Astrophysics::Cosmology and Extragalactic Astrophysics, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

National audience; Radio astronomy is a passive service and is equipped to observe extremely weak signals from outer space. The sensitivity of current state-of-the-art telescopes is over ten orders of magnitude higher than in most communications systems. Although radio telescopes are best located in relatively remote areas, astronomical observations may be still hampered by man-made radio frequency interference (RFI). In this paper we will consider different interference mitigation options. After a quick overview of techniques already implemented in current radio telescopes, we will focus on the innovative possibilities induced by the new generation of radio telescopes. In particular, phased array architecture can lead to interesting spatial filtering approaches. Examples on real data from LOFAR and from Nançay radio telescopes will be shown.

Published
2013

11. FAN : étude d'antennes en réseau au foyer du radiotélescope de Nançay

Author

Martin, J.-M., Pezzani, J., Dumez-Viou, C., Ansari, R., Magneville, C., Yèche, C., Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Focal plane arrays, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], radiotélescope décimétrique de Nançay, Nançay decimetric radio telescope, Réseaux d'antennes au foyer, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract

Communications consultables sur http://ursi-france.institut-telecom.fr; International audience; Le NRT (Nançay Radio Telescope) est l'un des trois radiotélescopes "single-dish" de la classe des 100m dans le monde. De nouvelles techniques observationnelles ainsi que des besoins scientifiques nouveaux pour de grands relevés aveugles ont émergés ces dernières années, et doivent utiliser des grands champs de vue. En particulier, la technologie des réseaux d'antennes au foyer est au cœur des recherches et développements de préparation à SKA. Nous présentons le projet FAN (Focal Array at Nançay) qui consiste en l'étude et la réalisation d'un premier prototype d'antenne à réseau phasé installé au foyer du NRT, qui utilise une chaîne de réception et d'acquisition développée par les laboratoires LAL /IN2P3 et SPP/IRFU/CEA. L'antenne est utilisée pour des observations de test depuis la fin 2010. Le système FAN et son fonctionnement sont décrits, ainsi que la méthode de calibration et les premiers résultats obtenus.

Published
2011

12. NenUFAR: Instrument description and science case

Author

Zarka, P., primary, Tagger, M., additional, Denis, L., additional, Girard, J. N., additional, Konovalenko, A., additional, Atemkeng, M., additional, Arnaud, M., additional, Azarian, S., additional, Barsuglia, M., additional, Bonafede, A., additional, Boone, F., additional, Bosma, A., additional, Boyer, R., additional, Branchesi, M., additional, Briand, C., additional, Cecconi, B., additional, Celestin, S., additional, Charrier, D., additional, Chassande-Mottin, E., additional, Coffre, A., additional, Cognard, I., additional, Combes, F., additional, Corbel, S., additional, Courte, C., additional, Dabbech, A., additional, Daiboo, S., additional, Dallier, R., additional, Dumez-Viou, C., additional, El Korso, M. N., additional, Falgarone, E., additional, Falkovych, I., additional, Ferrari, A., additional, Ferrari, C., additional, Ferriere, K., additional, Fevotte, C., additional, Fialkov, A., additional, Fullekrug, M., additional, Gerard, E., additional, Griebmeier, J.-M., additional, Guiderdoni, B., additional, Guillemot, L., additional, Hessels, J., additional, Koopmans, L., additional, Kondratiev, V., additional, Lamy, L., additional, Lanz, T., additional, Larzabal, P., additional, Lehnert, M., additional, Levrier, F., additional, Loh, A., additional, Macario, G., additional, Maintoux, J.-J., additional, Martin, L., additional, Mary, D., additional, Masson, S., additional, Miville-Deschenes, M.-A., additional, Oberoi, D., additional, Panchenko, M., additional, Pandey-Pommier, M., additional, Petiteau, A., additional, Pincon, J.-L., additional, Revenu, B., additional, Rible, F., additional, Richard, C., additional, Rucker, H. O., additional, Salome, P., additional, Semelin, B., additional, Serylak, M., additional, Smirnov, O., additional, Stappers, B., additional, Taffoureau, C., additional, Tasse, C., additional, Theureau, G., additional, Tokarsky, P., additional, Torchinsky, S., additional, Ulyanov, O., additional, van Driel, W., additional, Vasylieva, I., additional, Vaubaillon, J., additional, Vazza, F., additional, Vergani, S., additional, Was, M., additional, Weber, R., additional, and Zakharenko, V., additional

Published
2015
Full Text
View/download PDF

13. A Single-FPGA Real-Time Dual Beam-Former With FX Correlation Capabilities: First Results at the Nançay Radio Telescope With the FAN Antenna Array

Author

Deschamps, H., primary, Viou, C., additional, Pezzani, J., additional, Abbon, P., additional, Ansari, R., additional, Beigbeder, C., additional, Breton, D., additional, Caceres, T., additional, Charlet, D., additional, Flouzat, C., additional, Kestener, P., additional, Magneville, C., additional, Mansoux, B., additional, Pailler, C., additional, Taurigna, M., additional, and Yeche, C., additional

Published
2013
Full Text
View/download PDF

14. A single-FPGA real-time dual beam-former with FX correlation capabilities. First results at the Nançay radio telescope with the FAN antenna array

Author

Deschamps, H., primary, Viou, C., additional, Pezzani, J., additional, Abbon, P., additional, Ansari, R., additional, Beigbeder, C., additional, Breton, D., additional, Caceres, T., additional, Charlet, D., additional, Flouzat, C., additional, Kestener, P., additional, Magneville, C., additional, Mansoux, B., additional, Pailler, C., additional, Taurigna, M., additional, and Yeche, C., additional

Published
2012
Full Text
View/download PDF

15. Geomagnetic origin of the radio emission from cosmic ray induced air showers observed by CODALEMA

Author

Ardouin, D., primary, Belletoile, A., additional, Berat, C., additional, Breton, D., additional, Charrier, D., additional, Chauvin, J., additional, Chendeb, M., additional, Cordier, A., additional, Dagoret-Campagne, S., additional, Dallier, R., additional, Denis, L., additional, Dumez-Viou, C., additional, Fabrice, C., additional, Garçon, T., additional, Garrido, X., additional, Gautherot, N., additional, Gousset, T., additional, Haddad, F., additional, Koang, D.H., additional, Lamblin, J., additional, Lautridou, P., additional, Lebrun, D., additional, Lecacheux, A., additional, Lefeuvre, F., additional, Martin, L., additional, Meyer, E., additional, Meyer, F., additional, Meyer-Vernet, N., additional, Monnier-Ragaigne, D., additional, Montanet, F., additional, Payet, K., additional, Plantier, G., additional, Ravel, O., additional, Revenu, B., additional, Riviere, C., additional, Saugrin, T., additional, Sourice, A., additional, Stassi, P., additional, Stutz, A., additional, and Valcares, S., additional

Published
2009
Full Text
View/download PDF

16. R&D at Nançay for radio astronomy detectors and systems

Author

Bosse, S., primary, Grima, M.-L., additional, Kenfack, G., additional, Viou, C., additional, Picard, P., additional, Pezzani, J., additional, Renaud, P., additional, Taffoureau, C., additional, Denis, L., additional, Coffre, A., additional, Thomas, I., additional, Torchinsky, S., additional, Martin, J.-M., additional, Gérard, E., additional, van Driel, W., additional, Lecacheux, A., additional, Colom, P., additional, Kerdraon, A., additional, Weber, R., additional, Ravier, P., additional, and Feliachi, R., additional

Published
2009
Full Text
View/download PDF

18. Pulsars with NenuFAR: backend and pipelines

Author

Cyril Tasse, A. Possenti, Serge Yerin, Siyuan Chen, L. Bondonneau, C. Viou, M. Serylak, G. Shaifullah, Richard Dallier, J. W. McKee, Z. Wu, Julien N. Girard, Baptiste Cecconi, J.-M. Grießmeier, V. I. Kondratiev, M. Tagger, L. Guillemot, M. Brionne, Maura Pilia, R. A. Main, A. Loh, Ismaël Cognard, P. Zarka, Joris P. W. Verbiest, Caterina Tiburzi, Lilian Martin, Carine Briand, Stephane Corbel, A. V. Bilous, G. Theureau, Olaf Wucknitz, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Universität Bielefeld = Bielefeld University, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Grahamstown, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Bondonneau, L, Griessmeier, J, Theureau, G, Cognard, I, Brionne, M, Kondratiev, V, Bilous, A, Mckee, J, Zarka, P, Viou, C, Guillemot, L, Chen, S, Main, R, Pilia, M, Possenti, A, Serylak, M, Shaifullah, G, Tiburzi, C, Verbiest, J, Wu, Z, Wucknitz, O, Yerin, S, Briand, C, Cecconi, B, Corbel, S, Dallier, R, Girard, J, Loh, A, Martin, L, Tagger, M, Tasse, C, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
Physics - Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 4/3, 01 natural sciences, frequency: high, Radio telescope, High Energy Physics - Phenomenology (hep-ph), Pulsar, Millisecond pulsar, Observatory, pulsars: general, 0103 physical sciences, site, Instrumentation (computer programming), structure, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), pulsar, Physics, radio wave, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Crab Pulsar, Astrophysics::Instrumentation and Methods for Astrophysics, resolution, Astronomy and Astrophysics, LOFAR, Instrumentation and Detectors (physics.ins-det), sensitivity, coherence, observatory, High Energy Physics - Phenomenology, frequency: low, Space and Planetary Science, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], dispersion, methods: observational, Astrophysics - Instrumentation and Methods for Astrophysics, performance, Radio wave
Abstract

NenuFAR (New extension in Nan\c{c}ay upgrading LoFAR) is a new radio telescope developed and built on the site of the Nan\c{c}ay Radio Observatory. It is designed to observe the largely unexplored frequency window from 10 to 85\,MHz, offering a high sensitivity across its full bandwidth. NenuFAR has started its "early science" operation in July 2019, with 58\% of its final collecting area being available. Pulsars are one of the major topics for the scientific exploitation of this frequency range and represent an important challenge in terms of instrumentation. Designing instrumentation at these frequencies is complicated by the need to compensate for the effects of both the interstellar medium and the ionosphere on the observed signal. Our real-time pipeline LUPPI (Low frequency Ultimate Pulsar Processing Instrumentation) is able to cope with a high data rate and to provide real-time coherent de-dispersion down to the lowest frequencies reached by NenuFAR (10\,MHz). The full backend functionality is described, as well as the main pulsar observing modes (folded, single-pulse, waveform, and dynamic spectrum). This instrumentation allowed us to detect 172 pulsars in our first targeted search below 85\,MHz, including 10 millisecond pulsars (6 of which detected for the first time below 100 MHz). We also present some of the "early science" results of NenuFAR on pulsars: a high frequency resolution mapping of PSR B1919$+$21's emission profile and a detailed observation of single-pulse sub-structures from PSR~B0809$+$74 down to 16\,MHz, the high rate of giant-pulse emission from the Crab pulsar detected at 68.7\,MHz (43 events/min), and the illustration of the very good timing performance of the instrumentation, allowing us to study dispersion measure variations in great detail., Comment: 13 pages, 14 figures, submitted to A&A

Published
2020

19. Redefining performance evaluation tools for real-time QRS complex classification systems.

Author

Ravier P, Leclerc F, Dumez-Viou C, and Lamarque G

Subjects
Algorithms, Computer Systems, Humans, Pattern Recognition, Automated methods, Sensitivity and Specificity, Arrhythmias, Cardiac diagnosis, Arrhythmias, Cardiac physiopathology, Artificial Intelligence, Diagnosis, Computer-Assisted methods, Electrocardiography methods, Heart Rate, Software
Abstract

In a heartbeat classification procedure, the detection of QRS complex waveforms is necessary. In many studies, this heartbeat extraction function is not considered: the inputs of the classifier are assumed to be correctly identified. This communication aims to redefine classical performance evaluation tools in entire QRS complex classification systems and to evaluate the effects induced by QRS detection errors on the performance of heartbeat classification processing (normal versus abnormal). Performance statistics are given and discussed considering the MIT/BIH database records that are replayed on a real-time classification system composed of the classical detector proposed by Hamilton and Tompkins, followed by a neural-network classifier. This study shows that a classification accuracy of 96.72% falls to 94.90% when a drop of 1.78% error rate is introduced in the detector quality. This corresponds to an increase of about 50% bad classifications.

Published
2007
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results