Search

Your search keyword '"Bähren L"' showing total 13 results
Start Over Author "Bähren L" Publication Type Magazines
13 results on '"Bähren L"'

1. Frequency spectra of cosmic ray air shower radio emission measured with LOPES*

Author

Nigl, A., Apel, W. D., Arteaga, J. C., Asch, T., Auffenberg, J., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., de Souza, V., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Isar, P. G., Kampert, K.-H., Kickelbick, D., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Łuczak, P., Manewald, M., Mathes, H. J., Mayer, H. J., Meurer, C., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Rautenberg, J., Rebel, H., Roth, M., Saftoiu, A., Schieler, H., Schmidt, A., Schröder, F., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., Nigl, A., Apel, W. D., Arteaga, J. C., Asch, T., Auffenberg, J., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., de Souza, V., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Isar, P. G., Kampert, K.-H., Kickelbick, D., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Łuczak, P., Manewald, M., Mathes, H. J., Mayer, H. J., Meurer, C., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Rautenberg, J., Rebel, H., Roth, M., Saftoiu, A., Schieler, H., Schmidt, A., Schröder, F., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., and Zensus, J. A.

Abstract

Aims. We wish to study the spectral dependence of the radio emission from cosmic-ray air showers around $100~{\rm PeV}$$(10^{17}~{\rm eV})$.

Published
2008
Full Text
View/download PDF

2. Direction identification in radio images of cosmic-ray air showers detected with LOPES and KASCADE

Author

Nigl, A., Apel, W. D., Arteaga, J. C., Asch, T., Auffenberg, J., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., de Souza, V., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Isar, P. G., Kampert, K.-H., Kickelbick, D., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Łuczak, P., Manewald, M., Mathes, H. J., Mayer, H. J., Meurer, C., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Rautenberg, J., Rebel, H., Roth, M., Saftoiu, A., Schieler, H., Schmidt, A., Schröder, F., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., Nigl, A., Apel, W. D., Arteaga, J. C., Asch, T., Auffenberg, J., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., de Souza, V., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Isar, P. G., Kampert, K.-H., Kickelbick, D., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Łuczak, P., Manewald, M., Mathes, H. J., Mayer, H. J., Meurer, C., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Rautenberg, J., Rebel, H., Roth, M., Saftoiu, A., Schieler, H., Schmidt, A., Schröder, F., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., and Zensus, J. A.

Abstract

Aims. We want to understand the emission mechanism of radio emission from air showers to determine the origin of high-energy cosmic rays. Therefore, we study the geometry of the air shower radio emission measured with LOPES and search for systematic effects between the direction determined on the radio signal and the direction provided by the particle detector array KASCADE.

Published
2008
Full Text
View/download PDF

3. VLBI observations of Jupiter with the initial test station of LOFAR and the Nançay decametric array

Author

Nigl, A., Zarka, P., Kuijpers, J., Falcke, H., Bähren, L., Denis, L., Nigl, A., Zarka, P., Kuijpers, J., Falcke, H., Bähren, L., and Denis, L.

Abstract

Aims.To demonstrate and test the capability of the next generation of low-frequency radio telescopes to perform high resolution observations across intra-continental baselines. Jupiter's strong burst emission is used to perform broadband full signal cross-correlations on time intervals of up to hundreds of milliseconds.

Published
2007
Full Text
View/download PDF

4. Amplified radio emission from cosmic ray air showers in thunderstorms

Author

Buitink, S., Apel, W. D., Asch, T., Badea, F., Bähren, L., Bekk, K., Bercuci, A., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Kampert, K.-H., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Mathes, H. J., Mayer, H. J., Meurer, C., Milke, J., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Nigl, A., Obenland, R., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Petrovic, J., Pierog, T., Plewnia, S., Rebel, H., Risse, A., Roth, M., Schieler, H., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., Zimmermann, D., Buitink, S., Apel, W. D., Asch, T., Badea, F., Bähren, L., Bekk, K., Bercuci, A., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Kampert, K.-H., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Mathes, H. J., Mayer, H. J., Meurer, C., Milke, J., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Nigl, A., Obenland, R., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Petrovic, J., Pierog, T., Plewnia, S., Rebel, H., Risse, A., Roth, M., Schieler, H., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., and Zimmermann, D.

Abstract

Context.The detection of radio pulses from cosmic ray air showers is a potentially powerful new detection mechanism for studying spectrum and composition of ultra high energy cosmic rays that needs to be understood in greater detail. The radiation consists in large part of geosynchrotron radiation. The intensity of this radiation depends, among other factors, on the energy of the primary particle and the angle of the shower axis with respect to the geomagnetic field.

Published
2007
Full Text
View/download PDF

5. Radio emission of highly inclined cosmic ray air showers measured with LOPES

Author

Petrovic, J., Apel, W. D., Asch, T., Badea, F., Bähren, L., Bekk, K., Bercuci, A., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Kampert, K.-H., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Mathes, H. J., Mayer, H. J., Meurer, C., Milke, J., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Nigl, A., Obenland, R., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Plewnia, S., Rebel, H., Risse, A., Roth, M., Schieler, H., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., Zimmermann, D., Petrovic, J., Apel, W. D., Asch, T., Badea, F., Bähren, L., Bekk, K., Bercuci, A., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Gemmeke, H., Ghia, P. L., Glasstetter, R., Grupen, C., Haungs, A., Heck, D., Hörandel, J. R., Horneffer, A., Huege, T., Kampert, K.-H., Kolotaev, Y., Krömer, O., Kuijpers, J., Lafebre, S., Mathes, H. J., Mayer, H. J., Meurer, C., Milke, J., Mitrica, B., Morello, C., Navarra, G., Nehls, S., Nigl, A., Obenland, R., Oehlschläger, J., Ostapchenko, S., Over, S., Petcu, M., Pierog, T., Plewnia, S., Rebel, H., Risse, A., Roth, M., Schieler, H., Sima, O., Singh, K., Stümpert, M., Toma, G., Trinchero, G. C., Ulrich, H., van Buren, J., Walkowiak, W., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A., and Zimmermann, D.

Abstract

Aims.The capability of radio antenna arrays to measure cosmic ray air showers with very large zenith angles is explored. This is important, since a possible neutrino detection has to fulfill two requirements. First: antennas should be able to detect very inclined cosmic ray air showers, and second: it should be possible to estimate the distance to the shower maximum, since neutrinos are most likely to travel far through the Earth's atmosphere without interaction and induce air showers close to the ground.

Published
2007
Full Text
View/download PDF

7. Observing pulsars and fast transients with LOFAR

Author

Stappers, B. W., Hessels, J. W. T., Alexov, A., Anderson, K., Coenen, T., Hassall, T., Karastergiou, A., Kondratiev, V. I., Kramer, M., van Leeuwen, J., Mol, J. D., Noutsos, A., Romein, J. W., Weltevrede, P., Fender, R., Wijers, R. A. M. J., Bähren, L., Bell, M. E., Broderick, J., Daw, E. J., Dhillon, V. S., Eislöffel, J., Falcke, H., Griessmeier, J., Law, C., Markoff, S., Miller-Jones, J. C. A., Scheers, B., Spreeuw, H., Swinbank, J., ter Veen, S., Wise, M. W., Wucknitz, O., Zarka, P., Anderson, J., Asgekar, A., Avruch, I. M., Beck, R., Bennema, P., Bentum, M. J., Best, P., Bregman, J., Brentjens, M., van de Brink, R. H., Broekema, P. C., Brouw, W. N., Brüggen, M., de Bruyn, A. G., Butcher, H. R., Ciardi, B., Conway, J., Dettmar, R.-J., van Duin, A., van Enst, J., Garrett, M., Gerbers, M., Grit, T., Gunst, A., van Haarlem, M. P., Hamaker, J. P., Heald, G., Hoeft, M., Holties, H., Horneffer, A., Koopmans, L. V. E., Kuper, G., Loose, M., Maat, P., McKay-Bukowski, D., McKean, J. P., Miley, G., Morganti, R., Nijboer, R., Noordam, J. E., Norden, M., Olofsson, H., Pandey-Pommier, M., Polatidis, A., Reich, W., Röttgering, H., Schoenmakers, A., Sluman, J., Smirnov, O., Steinmetz, M., Sterks, C. G. M., Tagger, M., Tang, Y., Vermeulen, R., Vermaas, N., Vogt, C., de Vos, M., Wijnholds, S. J., Yatawatta, S., and Zensus, A.

Abstract

Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric “radio window”: 10–240 MHz, that will greatly facilitate observing pulsars at low radio frequencies. Through the huge collecting area, long baselines, and flexible digital hardware, it is expected that LOFAR will revolutionize radio astronomy at the lowest frequencies visible from Earth. LOFAR is a next-generation radio telescope and a pathfinder to the Square Kilometre Array (SKA), in that it incorporates advanced multi-beaming techniques between thousands of individual elements. We discuss the motivation for low-frequency pulsar observations in general and the potential of LOFAR in addressing these science goals. We present LOFAR as it is designed to perform high-time-resolution observations of pulsars and other fast transients, and outline the various relevant observing modes and data reduction pipelines that are already or will soon be implemented to facilitate these observations. A number of results obtained from commissioning observations are presented to demonstrate the exciting potential of the telescope. This paper outlines the case for low frequency pulsar observations and is also intended to serve as a reference for upcoming pulsar/fast transient science papers with LOFAR.

Published
2011
Full Text
View/download PDF

8. Reconstruction of the energy and depth of maximum of cosmic-ray air showers from LOPES radio measurements.

Author

Apel, W. D., Arteaga-Velazquez, J. C., Bähren, L., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Cantoni, E., Chiavassa, A., Daumiller, K., de Souza, V., Di Pierro, F., Doll, P., Engel, R., Falcke, H., Fuchs, B., Fuhrmann, D., and Gemmeke, H.

Subjects
*COSMIC ray showers, *RADIO interferometers, *COMPUTER simulation, *NUCLEAR energy
Abstract

LOPES is a digital radio interferometer located at Karlsruhe Institute of Technology (KIT), Germany, that measures radio emission from extensive air showers at MHz frequencies in coincidence with KASCADE-Grande. In this article, we explore a method (slope method) that leverages the slope of the measured radio lateral distribution to reconstruct crucial attributes of primary cosmic rays. First, we present an investigation of the method on the basis of pure simulations. Second, we directly apply the slope method to LOPES measurements. Applying the slope method to simulations, we obtain uncertainties on the reconstruction of energy and depth of shower maximum (Xmax) of 13% and 50 g/cm2, respectively. Applying it to LOPES measurements, we are able to reconstruct energy and Xmax of individual events with upper limits on the precision of 20%-25% for the primary energy and 95 g/cm² for Xmax, despite strong human-made noise at the LOPES site. [ABSTRACT FROM AUTHOR]

Published
2014
Full Text
View/download PDF

9. The LOPES experiment

Author

Link, Katrin, Apel, W.D., Arteaga, J.C., Asch, T., Bähren, L., Bekk, K., Bertaina, M., Biermann, P.L., Blümer, J., Bozdog, H., Brancus, I.M., Buchholz, P., Buitink, S., Cantoni, E., Chiavassa, A., Daumiller, K., de Souza, V., Doll, P., Engel, R., and Falcke, H.

Subjects
*COSMIC ray showers, *PHYSICS experiments, *ELECTRONS, *COSMIC magnetic fields, *PARTICLES (Nuclear physics), *DETECTORS, *ELECTRIC fields, *MEASUREMENT
Abstract

Cosmic ray particles hit the Earthʼs atmosphere and induce extensive air showers (EAS). These EAS mainly consist of electrons and positrons that produce radio emission due to their interaction with the Earthʼs magnetic field. Measuring this radio emission is the purpose of the LOPES (LOFAR Prototype Station) experiment. LOPES is located at Campus North of the Karlsruhe Institute of Technology at the same site as the EAS particle detector KASCADE-Grande. Since the first measurements in 2003, LOPES was improved by various experimental setups and could establish the radio technique. By now, detailed studies of the measured radio signal are performed, like the behaviour of the lateral distribution or the polarization of the electric field. Furthermore, with LOPES the dependence of the radio pulse on properties of the incoming cosmic ray, like primary energy, primary mass, or incoming direction is investigated. In this article we describe the different LOPES setups, next we explain our standard analysis procedure and then we discuss some highlights of our recent results. [ABSTRACT FROM AUTHOR]

Published
2011
Full Text
View/download PDF

10. Recent results of the LOPES experiment

Author

Haungs, A., Apel, W.D., Arteaga, J.C., Asch, T., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P.L., Blümer, J., Bozdog, H., Brancus, I.M., Brüggemann, M., Buchholz, P., Buitink, S., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., and de Souza, V.

Subjects
*PHYSICS experiments, *COSMIC rays, *COSMIC ray showers, *CALIBRATION, *DIGITAL signal processing
Abstract

LOPES measures radio pulses from extensive air showers and aims to calibrate the emitted signal in the primary energy range of 1016–1018 eV. LOPES, a digital radio interferometer using high bandwidths and fast data processing, is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and profits from the reconstructed air shower observables of KASCADE-Grande. We report about recent analysis results of the radio signals measured by LOPES. [Copyright &y& Elsevier]

Published
2009
Full Text
View/download PDF

11. Recent Results from KASCADE-Grande and LOPES

Author

Kampert, K.-H., Apel, W.D., Arteaga, J.C., Asch, T., Badea, F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P.L., Blümer, J., Bozdog, H., Brancus, I.M., Brüggemann, M., Buchholz, P., Buitink, S., Cantoni, E., Chiavassa, A., Cossavella, F., Daumiller, K., and de Souza, V.

Subjects
*COSMIC ray showers, *PHYSICS experiments, *RADIATION shielding, *NUCLEAR track detectors, *SPECTRUM analysis, *GEOMETRICAL constructions
Abstract

KASCADE-Grande is an extensive air-shower experiment located at Forschungszentrum Karlsruhe, Germany. Main parts of the experiment are the Grande array spread over an area of , the original KASCADE array covering with unshielded and shielded detectors, and additional muon tracking devices. This multi-detector system allows to investigate the energy spectrum, composition, and anisotropies of cosmic rays in the energy range up to 1 EeV. LOPES is co-located at the same site to measure radio pulses from extensive air showers in coincidence with KASCADE-Grande. It consists of 30 digital antennas operated in different geometrical configurations. Read out is performed at high bandwidths and rate data processing with the aim to calibrate the emitted signal in the primary energy range of by making use of reconstructed air-shower observables of KASCADE-Grande. An overview on the performance of both experiments will be given and recent analysis results be reported. [Copyright &y& Elsevier]

Published
2009
Full Text
View/download PDF

12. Cosmic Ray Air Shower Detection with LOPES

Author

Haungs, A., Apel, W.D., Arteaga, J.C., Asch, T., Badea, A.F., Bähren, L., Bekk, K., Bertaina, M., Biermann, P.L., Blümer, J., Bozdog, H., Brancus, I.M., Brüggemann, M., Buchholz, P., Buitink, S., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., and Di Pierro, F.

Subjects
*COSMIC rays, *ASTROPHYSICAL radiation, *PHYSICS, *NUCLEAR physics
Abstract

LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to investigate radio pulses from extensive air showers experimentally and theoretically. Data taken during half a year of operation of 10 LOPES antennas (LOPES-10), triggered by EAS observed with KASCADE-Grande have been analysed. We report about the results of correlations with shower parameters present in the radio signals measured by LOPES-10. The extended setup LOPES-30 consists of 30 antennas which have an absolute calibration and the data of which will be compared with expectations from detailed Monte-Carlo simulations. In addition, LOPES operates antennas of a different type (LOPESSTAR) which are optimized for an application at the Pierre Auger Observatory. [Copyright &y& Elsevier]

Published
2008
Full Text
View/download PDF

13. Radio detection of cosmic ray air showers with LOPES

Author

Huege, T., Apel, W.D., Asch, T., Badea, A.F., Bähren, L., Bekk, K., Bercuci, A., Bertaina, M., Biermann, P.L., Blümer, J., Bozdog, H., Brancus, I.M., Buitink, S., Brüggemann, M., Buchholz, P., Butcher, H., Chiavassa, A., Cossavella, F., Daumiller, K., and Di Pierro, F.

Subjects
*COSMIC ray showers, *RADIO detectors, *INTERFEROMETRY, *SOLAR radio emission
Abstract

In the last few years, radio detection of cosmic ray air showers has experienced a true renaissance, becoming manifest in a number of new experiments and simulation efforts. In particular, the LOPES project has successfully implemented modern interferometric methods to measure the radio emission from extensive air showers. LOPES has confirmed that the emission is coherent and of geomagnetic origin, as expected by the geosynchrotron mechanism, and has demonstrated that a large scale application of the radio technique has great potential to complement current measurements of ultra-high energy cosmic rays. We describe the current status, most recent results and open questions regarding radio detection of cosmic rays and give an overview of ongoing research and development for an application of the radio technique in the framework of the Pierre Auger Observatory. [Copyright &y& Elsevier]

Published
2007
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results