Author: "D. Hakobyan" - Searchworks@Jio Institute Digital Library Search Results

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46 results on '"D. Hakobyan"'

1. Poems syndrome: a 'multifaceted' entity of plasma cell disorder

Author: D. Sevoyan, D. Hakobyan, D. Meliksetyan, D. Ter-Grigoryan, D. Ghazaryan, D. Grigoryan, and D. Martirosyan
Subjects: Diseases of the blood and blood-forming organs, RC633-647.5
Published: 2020
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2. Clinical and Microbiological Risk Factors of Periodontal Diseases in the Occurrence of Premature Delivery

Author: D, Hakobyan, primary, G, Okoev, additional, and H, Arustamyan, additional
Published: 2020
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3. FADC signal reconstruction for the MAGIC telescope

Author: H. Anderhub, K. Shinozaki, Stefano Ciprini, M. Camara, R. Mirzoyan, E. Carmona, Roberta Zanin, Florian Goebel, M. V. Fonseca, P. Jacon, Jorge Andres Lopez Lopez, D. Hakobyan, F. Zandanel, E. Domingo-Santamaría, J. Hose, Jelena Ninkovic, Michela Fagiolini, Oriana Mansutti, Francesco Dazzi, M. Rissi, S. Mizobuchi, Tadeusz Wibig, V. Scalzotto, M. A. Lopez, T. Schweizer, Francesco Longo, W. Wittek, Marc Ribó, J. Zapatero, D. Tescaro, Pol Bordas, Dorota Sobczyńska, M. T. Costado, V. Vitale, C. C. Hsu, Miriam Lucio Martinez, Justin Albert, M. Asensio, Steven N. Shore, V. Curtef, R. Schmitt, Riccardo Paoletti, Takashi Saito, Masahiro Teshima, Igor Oya, Jose Flix, G. Maneva, Daniel Nieto, Daniel Kranich, C. Merck, E. Aliu, E. Prandini, P. Antoranz, Elina Lindfors, Ll. Font, R. K. Bock, C. Baixeras, A. Sillanpää, A. Herrero, A. Saggion, L. O. Takalo, Adrian Biland, S. Rügamer, C. Delgado, V. Danielyan, Masaaki Hayashida, Antonio Stamerra, Juan Abel Barrio, Diego F. Torres, Ciro Bigongiari, M. Pasanen, R. G. Pegna, Markus Gaug, K. Berger, A. Armada, J. Rico, Jose Luis Contreras, Mosè Mariotti, M. Garczarczyk, Josep M. Paredes, M. Shayduk, T. Jogler, Ashot Chilingarian, Juan Cortina, E. Oña-Wilhelmi, R. Kritzer, A. Raymers, A. De Angelis, R. Firpo, B. De Lotto, D. Höhne, L. S. Stark, R. J. García-López, N. Puchades, A. Piccioli, Nicola Galante, R. Kosyra, Robert Wagner, Saverio Lombardi, H. Bartko, E. Fernandez, E. Lorenz, I. Britvitch, Daniel Ferenc, Maria Giller, Thomas Bretz, H. Vankov, Abelardo Moralejo, Michele Doro, N. Otte, M. Panniello, P. Sartori, D. Mazin, Manel Errando, Kari Nilsson, Wolfgang Rhode, Julia Becker, S. Commichau, Wlodek Bednarek, Jose Miguel Miranda, Daniela Dorner, A. Laille, Petar Temnikov, M. Fuchs, Massimo Persic, Mario Meucci, J. A. Coarasa, Valentí Bosch-Ramon, L. Peruzzo, V. Scapin, R. de los Reyes, Nicola Turini, P. Majumdar, N. Sidro, M. Meyer, D. Pascoli, A. Robert, Felicitas Pauss, T. Hengstebeck, Denis Bastieri, Alvaro Sanchez, Karl Mannheim, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. d., los Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, N., Puchade, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: signal sampling, Nuclear and High Energy Physics, Photomultiplier, Physics::Instrumentation and Detectors, Very High Energy Gamma Ray Astronomy, Detectors, MAGIC telescope, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Signal, law.invention, Telescope, Optics, IMAGING CHERENKOV DETECTOR, law, Calibration, MAGIC (telescope), Instrumentation, Cherenkov radiation, CALIBRATION, Physics, Signal reconstruction, business.industry, GAMMA-RAY ASTRONOMY, SYSTEM, TESTS, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, Detector, business
Abstract: Until April 2007 the MAGIC telescope used a 300 MSamples/s FADC system to sample the shaped PMT signals produced by the captured Cherenkov photons of air showers. Different algorithms to reconstruct the signal from the read-out samples (extractors) have been implemented and are described and compared. Criteria based on the obtained charge and time resolution/bias are defined and used to judge the different extractors, by applying them to calibration, cosmic and pedestal signals. The achievable charge and time resolution have been derived as functions of the incident number of photo-electrons., Accepted for publication in NIM A
Published: 2008
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4. Unfolding of differential energy spectra in the MAGIC experiment

Author: E. Fernandez, M. I. Martínez, K. Shinozaki, V. Danielyan, R. K. Bock, N. Sidro, A. Laille, J. M. Paredes, Antonio Stamerra, Francesco Longo, W. Wittek, D. Pascoli, Roberta Zanin, M. Fuchs, Massimo Persic, F. Pauss, E. Lorenz, T. Hengstebeck, E. Domingo-Santamaría, Michela Fagiolini, Oriana Mansutti, M. Pasanen, Abelardo Moralejo, R. de los Reyes, Stefano Ciprini, D. Hakobyan, S. Mizobuchi, Denis Bastieri, A. Robert, Nicola Turini, Jelena Ninkovic, R. Firpo, Alvaro Sanchez, Marc Ribó, K. Nilsson, M. T. Costado, C. Baixeras, H. Anderhub, Julia Becker, Francesco Dazzi, S. Commichau, J. A. Coarasa, D. Tescaro, Tadeusz Wibig, Dorota Sobczyńska, P. Antoranz, J. Zapatero, Justin Albert, Jose Miguel Miranda, Juan Abel Barrio, V. Vitale, I. Oya, J. Rico, G. Maneva, A. Saggion, F. Zandanel, Daniel Nieto, Adrian Biland, Mario Meucci, E. Carmona, Markus Gaug, N. Otte, C. Merck, C. Delgado, K. Berger, L. Peruzzo, K. Mannheim, E. Aliu, Elina Lindfors, L. S. Stark, M. Meyer, Daniel Mazin, Riccardo Paoletti, Michele Doro, M. V. Fonseca, M. Garczarczyk, S. Rügamer, Elisa Prandini, V. Curtef, M. Camara, Ashot Chilingarian, Maria Giller, M. Shayduk, Diego F. Torres, Ciro Bigongiari, Manel Errando, L. O. Takalo, A. Raymers, Pol Bordas, A. Herrero, Mosè Mariotti, A. De Angelis, A. Piccioli, Nicola Galante, P. Sartori, Saverio Lombardi, R. Kritzer, M. Asensio, B. De Lotto, M. López, R. Schmitt, R. Kosyra, Robert Wagner, H. Bartko, E. Oña-Wilhelmi, N. Puchades, P. Jacon, C. C. Hsu, A. Armada, Thomas Bretz, S. N. Shore, R. Mirzoyan, M. Panniello, Masahiro Teshima, Wolfgang Rhode, T. Schweizer, I. Britvitch, A. Sillanpää, W. Bednarek, Jose Flix, Ll. Font, Takashi Saito, Daniela Dorner, J. Hose, Petar Temnikov, Valentí Bosch-Ramon, V. Scapin, Florian Goebel, Masaaki Hayashida, Jose Luis Contreras, Juan Cortina, R. Pegna, Daniel Ferenc, H. Vankov, P. Majumdar, Jorge Andres Lopez Lopez, V. Scalzotto, M. Rissi, D. Kranich, T. Jogler, D. Höhne, R. J. García-López, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., C., Delgado, Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garc\ia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., H\ohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Mart\inez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., O\~na Wilhelmi, N., Otte, I., Oya, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, N., Puchade, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: Nuclear and High Energy Physics, statistics techniques, DISTRIBUTIONS, ENTROPY, regularization, unfolding, Very High Energy Gamma-ray Astronomy, Calibrations, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Spectral line, Nuclear physics, Software, gamma ray astronomy, Statistical analysis, Statistical physics, Instrumentation, Physics, Quantitative Biology::Biomolecules, business.industry, Astrophysics (astro-ph), Very high energy gamma ray astronomy, Electrónica, Física nuclear, Electricidad, business
Abstract: The paper describes the different methods, used in the MAGIC experiment, to unfold experimental energy distributions of cosmic ray particles (gamma-rays). Questions and problems related to the unfolding are discussed. Various procedures are proposed which can help to make the unfolding robust and reliable. The different methods and procedures are implemented in the MAGIC software and are used in most of the analyses., Comment: Submitted to NIM A
Published: 2007
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5. Variable Very High Energy γ‐Ray Emission from Markarian 501

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. K. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch‐Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, C. Delgado, R. de los Reyes, B. De Lotto, E. Domingo‐Santamaria, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernandez, R. Firpo, J. Flix, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. J. Garcia‐Lopez, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, D. Hohne, J. Hose, D. Hrupec, C. C. Hsu, P. Jacon, T. Jogler, R. Kosyra, D. Kranich, R. Kritzer, A. Laille, E. Lindfors, S. Lombardi, F. Longo, J. Lopez, M. Lopez, E. Lorenz, P. Majumdar, G. Maneva, K. Mannheim, O. Mansutti, M. Mariotti, M. Martinez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, D. Nieto, K. Nilsson, J. Ninkovic, E. Ona‐Wilhelmi, N. Otte, I. Oya, D. Paneque, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribo, J. Rico, M. Rissi, A. Robert, S. Rugamer, A. Saggion, T. Saito, A. Sanchez, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpaa, D. Sobczynska, A. Stamerra, L. S. Stark, L. Takalo, F. Tavecchio, P. Temnikov, D. Tescaro, M. Teshima, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, F. Zandanel, R. Zanin, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D. L., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, D., Hrupec, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, F., Tavecchio, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: PARTICLE-ACCELERATION, Photon, ACTIVE GALACTIC NUCLEI, BL-LAC OBJECTS, CHERENKOV TELESCOPE SYSTEM, LOG-PARABOLIC SPECTRA, 23 DAY PERIODICITY, BLACK-HOLE MODELS, X-RAY, MKN 501, MULTIWAVELENGTH OBSERVATIONS, Flux, Electron, Astrophysics, 01 natural sciences, Spectral line, Luminosity, law.invention, law, 0103 physical sciences, Blazar, 010303 astronomy & astrophysics, Physics, 010308 nuclear & particles physics, Gamma ray, Active Galactic Nuclei, Astronomy and Astrophysics, MAGIC telescope, Very High Energy Gamma-ray Astronomy, Space and Planetary Science, Electrónica, Física nuclear, Electricidad, Markarian 501, BL Lac, AGN, VHE gamma-ray, imaging air Cherenkov telescope, MAGIC, Flare
Abstract: The blazar Markarian 501 (Mrk 501) was observed at energies above 0.10 TeV with the MAGIC telescope from May through July 2005. The high sensitivity of the instrument enabled the determination of the flux and spectrum of the source on a night-by-night basis. Throughout our observational campaign, the flux from Mrk 501 was found to vary by an order of magnitude. Intra-night flux variability with flux-doubling times down to 2 minutes was observed during the two most active nights, namely June 30 and July 9. These are the fastest flux variations ever observed in Mrk 501. The ~20-minute long flare of July 9 showed an indication of a 4 +/- 1 min time delay between the peaks of F(1.2 TeV), which may indicate a progressive acceleration of electrons in the emitting plasma blob. The flux variability was quantified for several energy ranges, and found to increase with the energy of the gamma-ray photons. The spectra hardened significantly with increasing flux, and during the two most active nights, a spectral peak was clearly detected at 0.43 +/- 0.06 TeV and 0.25 +/- 0.07 TeV, respectively for June 30 and July 9. There is no evidence of such spectral feature for the other nights at energies down to 0.10 TeV, thus suggesting that the spectral peak is correlated with the source luminosity. These observed characteristics could be accommodated in a Synchrotron-Self-Compton (SSC) framework in which the increase in gamma-ray flux is produced by a freshly injected (high energy) electron population.
Published: 2007
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6. MAGIC Upper Limits on the Very High Energy Emission from Gamma‐Ray Bursts

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch‐Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, S. Ciprini, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, C. Delgado, R. de los Reyes, B. De Lotto, E. Domingo‐Santamaria, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernandez, R. Firpo, J. Flix, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. Garcia‐Lopez, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, D. Hohne, J. Hose, C. C. Hsu, P. Jacon, T. Jogler, O. Kalekin, R. Kosyra, D. Kranich, R. Kritzer, A. Laille, T. Lenisa, P. Liebing, E. Lindfors, S. Lombardi, F. Longo, J. Lopez, M. Lopez, E. Lorenz, P. Majumdar, G. Maneva, K. Mannheim, O. Mansutti, M. Mariotti, M. Martinez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, J. Ninkovic, E. Ona‐Wilhelmi, N. Otte, I. Oya, D. Paneque, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, M. Poller, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribo, J. Rico, M. Rissi, A. Robert, S. Rugamer, A. Saggion, A. Sanchez, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpaa, D. Sobczynska, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, R. Zanin, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. d., los Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, O., Kalekin, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, and J., Zapatero
Subjects: High energy, gamma ray astronomy, IMAGING CHERENKOV DETECTOR, Astrophysics::High Energy Astrophysical Phenomena, Very High Energy Gamma-ray Astronomy, Gamma-ray Bursts, MAGIC telescope, Extrapolation, FIREBALLS, Astrophysics, COMPTON EMISSION, Power law, GRB 050713A, Observacions astronòmiques, SEARCH, Gamma ray astronomy, Astronomia de raigs gamma, SPECTRA, MAGIC (telescope), LONG-DURATION, TEV EMISSION, AFTERGLOWS, SYNCHROTRON, COMPONENT, Zenith, Physics, Scattering, Attenuation, Astronomy and Astrophysics, Redshift, Space and Planetary Science, Gamma-ray Burst, Electrónica, Física nuclear, Electricidad, Astronomical observations
Abstract: During its first data cycle, between 2005 and the beginning of 2006, the fast repositioning system of the MAGIC telescope allowed the observation of nine different gamma-ray bursts as possible sources of very high energy gamma-rays. These observations were triggered by alerts from Swift, HETE-2, and INTEGRAL; they started as quickly as possible after the alerts and lasted for several minutes, with an energy threshold varying between 80 and 200 GeV, depending on the zenith angle of the burst. No evidence for gamma signals was found, and upper limits for the flux were derived for all events using the standard analysis chain of MAGIC. For the bursts with measured redshifts, the upper limits are compatible with a power-law extrapolation, when the intrinsic fluxes are evaluated taking into account the attenuation due to the scattering in the metagalactic radiation field.
Published: 2007
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7. Constraints on the Steady and Pulsed Very High Energy Gamma‐Ray Emission from Observations of PSR B1951 \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $+$ \end{document} 32/CTB 80 with the MAGIC Telescope

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. K. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch‐Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, C. Delgado, R. de los Reyes, B. De Lotto, E. Domingo‐Santamaria, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernandez, R. Firpo, J. Flix, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. Garcia‐Lopez, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, K. Hirotani, D. Hohne, J. Hose, C.‐C. Hsu, P. Jacon, T. Jogler, R. Kosyra, D. Kranich, R. Kritzer, A. Laille, E. Lindfors, S. Lombardi, F. Longo, J. Lopez, M. Lopez, E. Lorenz, P. Majumdar, G. Maneva, K. Mannheim, O. Mansutti, M. Mariotti, M. Martinez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, D. Nieto, K. Nilsson, J. Ninković, E. Ona‐Wilhelmi, N. Otte, I. Oya, D. Paneque, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, M. Poller, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribo, J. Rico, M. Rissi, A. Robert, S. Rugamer, A. Saggion, A. Sanchez, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpaa, D. Sobczyńska, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, F. Zandanel, R. Zanin, and J. Zapatero
Subjects: Physics, High energy, Nebula, Photon, Pulsar, Space and Planetary Science, Astrophysics::High Energy Astrophysical Phenomena, Gamma ray, Cutoff, Flux, Astronomy and Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We report on very high energy gamma-observations with the MAGIC Telescope of the pulsar PSR B1951+32 and its associated nebula, CTB 80. Our data constrain the cutoff energy of the pulsar to be less than 32 GeV, assuming the pulsed gamma-ray emission to be exponentially cut off. The upper limit on the flux of pulsed gamma-ray emission above 75 GeV is 4.3*10^-11 photons cm^-2 sec^-1, and the upper limit on the flux of steady emission above 140 GeV is 1.5*10^-11 photons cm^-2 sec^-1. We discuss our results in the framework of recent model predictions and other studies.
Published: 2007
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8. Observation of VHE gamma-rays from Cassiopeia A with the MAGIC telescope

Author: Valentí Bosch-Ramon, Maria Giller, V. Scapin, M. Camara, V. Vitale, Abelardo Moralejo, Jorge Andres Lopez Lopez, E. Carmona, A. Sillanpää, H. Anderhub, T. Schweizer, V. Scalzotto, P. Jacon, P. Sartori, Daniela Dorner, Francesco Longo, W. Wittek, Mosè Mariotti, P. Antoranz, A. Saggion, Masahiro Teshima, Adrian Biland, M. Poller, J. Hose, C. Baixeras, Jelena Ninkovic, Petar Temnikov, M. López, Markus Gaug, Elisa Prandini, Florian Goebel, Riccardo Paoletti, W. Bednarek, Manel Errando, Jose Flix, F. Pauss, Saverio Lombardi, Julia Becker, Ll. Font, A. Robert, S. Commichau, A. Armada, R. Kritzer, Francesco Dazzi, Juan Abel Barrio, Ashot Chilingarian, V. Danielyan, B. De Lotto, V. Curtef, L. S. Stark, Masaaki Hayashida, E. Oña-Wilhelmi, Jose Luis Contreras, J. M. Paredes, Antonio Stamerra, D. Tescaro, I. Britvitch, H. Bartko, Jose Miguel Miranda, Juan Cortina, Tadeusz Wibig, J. A. Coarasa, L. O. Takalo, E. Lorenz, N. Puchades, E. Fernandez, R. Pegna, Pol Bordas, Michele Doro, K. Nilsson, R. Firpo, F. Zandanel, N. Tonello, J. Rico, Thomas Bretz, S. N. Shore, Diego F. Torres, Ciro Bigongiari, R. Mirzoyan, A. Laille, M. Shayduk, N. Otte, M. Pasanen, A. Raymers, A. De Angelis, L. Peruzzo, R. de los Reyes, Nicola Turini, C. Delgado, A. Piccioli, K. Berger, David Paneque, M. Panniello, M. I. Martínez, Nicola Galante, G. Maneva, N. Sidro, Wolfgang Rhode, D. Pascoli, M. Fuchs, Massimo Persic, R. Kosyra, Robert Wagner, K. Mannheim, M. Meyer, C. C. Hsu, M. Garczarczyk, C. Merck, E. Aliu, R. Schmitt, Elina Lindfors, Daniel Mazin, S. Rügamer, Michela Fagiolini, Oriana Mansutti, Dorota Sobczyńska, Justin Albert, J. Zapatero, I. Oya, K. Shinozaki, Roberta Zanin, E. Domingo-Santamaría, A. Herrero, T. Jogler, D. Höhne, R. J. García-López, R. K. Bock, M. Rissi, D. Kranich, T. Hengstebeck, Denis Bastieri, D. Hakobyan, S. Mizobuchi, Alvaro Sanchez, Marc Ribó, M. T. Costado, Daniel Ferenc, H. Vankov, P. Majumdar, Mario Meucci, M. V. Fonseca, Universitat de Barcelona, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. d., los Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, N., Puchade, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: Astrofísica, Photon, Raigs còsmics, Astronomy, PROGENITOR, Astrophysics, law.invention, Raigs gamma, law, Supernova remnant, Physics, SUPERNOVA-REMNANTS, Supernoves, Astrophysics (astro-ph), Gamma ray, 5 GHZ, Particle acceleration, Supernovae, Electrónica, Física nuclear, Electricidad, Very High Energy Gamma-ray Astronomy, Supernova remnants, MAGIC telescope, Telescopis espacials, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Cosmic ray, Astrophysics::Cosmology and Extragalactic Astrophysics, ACCELERATION, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, Space telescopes, Telescope, Angular resolution, Astrophysics::Galaxy Astrophysics, Gamma rays, Astronomy and Astrophysics, Cassiopeia A, Space and Planetary Science, EMISSION, Astronomia, High Energy Physics::Experiment
Abstract: We searched for very high energy (VHE) gamma-ray emission from the supernova remnant Cassiopeia A. The shell-type supernova remnant Cassiopeia A was observed with the 17 meter MAGIC telescope between July 2006 and January 2007 for a total time of 47 hours. The source was detected above an energy of 250 GeV with a significance of 5.2sigma and a photon flux above 1 TeV of (7.3+-0.7_stat+-2.2_sys)10^-13 cm^-2s^-1. The photon spectrum is compatible with a power law dN/dE = A E^-Gamma with a photon index Gamma=2.3+-0.2_stat+-0.2_sys. The source is point-like within the angular resolution of the telescope., Comment: 4 pages, 4 figures, submitted to A&A
Published: 2007

9. Discovery of very high energy gamma-ray emission from the low-frequency peaked BL Lacertae object BL Lacertae

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. K. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. D. Angelis, C. Delgado, R. D. L. Reyes, B. D. Lotto, E. Domingo Santamaria, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernandez, R. Firpo, J. Flix, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. Garcia Lopez, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, D. Hohne, J. Hose, C. C. Hsu, P. Jacon, T. Jogler, R. Kosyra, D. Kranich, R. Kritzer, A. Laille, E. Lindfors, S. Lombardi, J. Lopez, M. Lopez, E. Lorenz, P. Majumdar, G. Maneva, K. Mannheim, O. Mansutti, M. Mariotti, M. Martinez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, J. Ninkovic, E. Ona Wilhelmi, N. Otte, I. Oya, D. Paneque, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, M. Poller, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribo, J. Rico, M. Rissi, A. Robert, S. Rugamer, A. Saggion, A. Sanchez, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpaa, D. Sobczynska, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, F. Zandanel, R. Zanin, J. Zapatero, LONGO, FRANCESCO, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D. L., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: High energy, Photon, Flux, FOS: Physical sciences, Astrophysics, Low frequency, Observacions astronòmiques, Gamma ray astronomy, Galaxies: individual: BL Lacertae, Astronomia de raigs gamma, MAGIC (telescope), Physics, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, Active Galactic Nuclei, Light curve, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, Electrónica, Física nuclear, Electricidad, BL Lac object, Astronomical observations
Abstract: The MAGIC collaboration observed BL Lacertae for 22.2 hr during 2005 August to December and for 26 hr during 2006 July to September. The source is the historical prototype and eponym of a class of low-frequency peaked BL Lacertae (LBL) objects. A very high energy (VHE) gamma-ray signal was discovered with a 5.1 sigma excess in the 2005 data. Above 200 GeV, an integral flux of 0.6+-0.2 x 10^(-11) cm^(-2) s^(-1) was measured, corresponding to approximately 3% of the Crab flux. The differential spectrum between 150 and 900 GeV is rather steep with a photon index of -3.6+-0.5. The light curve shows no significant variability during the observations in 2005. For the first time a clear detection of VHE gamma-ray emission from an LBL object was obtained with a signal below previous upper limits. The 2006 data show no significant excess. This drop in flux follows the observed trend in optical activity., Comment: Accepted for publication in ApJ Letters, 4 pages, 5 figures, Figure-5 revised, Minor corrections following the referee report
Published: 2007

10. Discovery of very high energy gamma radiation from IC 443 with the MAGIC telescope

Author: Daniela Dorner, K. Berger, Manel Errando, H. Anderhub, M. Shayduk, J. Hose, A. Raymers, A. De Angelis, Petar Temnikov, M. Camara, A. Piccioli, Nicola Galante, M. I. Martínez, T. Hengstebeck, P. Jacon, V. Danielyan, Florian Goebel, Dorota Sobczyńska, I. Britvitch, Justin Albert, M. Rissi, C. Merck, J. M. Paredes, P. Sartori, Denis Bastieri, N. Puchades, Antonio Stamerra, Elina Lindfors, N. Otte, D. Kranich, V. Curtef, A. Sillanpää, Takashi Saito, M. López, Alvaro Sanchez, Daniel Mazin, A. Armada, Masahiro Teshima, E. Oña-Wilhelmi, R. J. García-López, D. Pascoli, S. Rügamer, D. Hakobyan, S. Mizobuchi, Thomas Bretz, A. Saggion, S. N. Shore, Elisa Prandini, Enrique Fernández, M. Fuchs, Massimo Persic, L. O. Takalo, R. Firpo, R. Schmitt, Marc Ribó, Juan Abel Barrio, Valentí Bosch-Ramon, R. Mirzoyan, Adrian Biland, Michele Doro, V. Scapin, Daniel Nieto, Markus Gaug, J. A. Coarasa, M. T. Costado, V. Vitale, Michela Fagiolini, Oriana Mansutti, Artemio Herrero, A. Robert, Mario Meucci, M. Panniello, Ashot Chilingarian, T. Jogler, E. Aliu, D. Höhne, C. Delgado, Francesco Longo, Wolfgang Rhode, K. Shinozaki, R. K. Bock, F. Pauss, T. Schweizer, R. Kosyra, Robert Wagner, M. V. Fonseca, F. Zandanel, L. S. Stark, J. Zapatero, Riccardo Paoletti, I. Oya, W. Wittek, P. Antoranz, Roberta Zanin, Daniel Ferenc, J. Rico, A. Laille, Mosè Mariotti, H. Vankov, N. Sidro, Julia Becker, S. Commichau, K. Nilsson, M. Pasanen, David Paneque, E. Domingo-Santamaría, P. Majumdar, C. C. Hsu, K. Mannheim, R. de los Reyes, Nicola Turini, M. Meyer, M. Garczarczyk, Jose Miguel Miranda, L. Peruzzo, Saverio Lombardi, Maria Giller, E. Carmona, G. Maneva, C. Baixeras, Pol Bordas, D. Tescaro, Tadeusz Wibig, E. Lorenz, V. Scalzotto, Masaaki Hayashida, Jose Luis Contreras, Juan Cortina, R. Pegna, W. Bednarek, Jose Flix, Ll. Font, Jelena Ninkovic, Francesco Dazzi, Diego F. Torres, Ciro Bigongiari, J. López, R. Kritzer, B. De Lotto, H. Bartko, Abelardo Moralejo, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. d., los Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: High energy, Supernova remnants, Astrophysics, Radiation, Power law, Coincident, Observacions astronòmiques, Supernova remnant, Gamma ray astronomy, Astronomia de raigs gamma, MAGIC (telescope), Physics, Supernoves, Astronomy, Astronomy and Astrophysics, Galactic plane, Very high energy gamma ray astronomy, Supernovae, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, Electrónica, Física nuclear, Electricidad, gamma rays: observations, Astronomical observations
Abstract: We report the detection of a new source of very high energy (VHE; E-gamma >= 100 GeV) gamma- ray emission located close to the Galactic plane, MAGIC J0616 + 225, which is spatially coincident with supernova remnant IC 443. The observations were carried out with the MAGIC telescope in the periods 2005 December-2006 January and 2006 December-2007 January. Here we present results from this source, leading to a VHE gamma-ray signal with a statistical significance of 5.7 sigma in the 2006/2007 data and a measured differential gamma-ray flux consistent with a power law, described as dN(gamma)/(dA dt dE) = (1.0 +/- 0.2) x 10(-11) (E/0.4 TeV)(-3.1 +/- 0.3) cm(-2) s(-1) TeV-1. We briefly discuss the observational technique used and the procedure implemented for the data analysis. The results are placed in the context of the multiwavelength emission and the molecular environment found in the region of IC 443.
Published: 2007

11. Detection of very high energy radiation from the BL lacertae object PG 1553+113 with the MAGIC telescope

Author: Michela Fagiolini, Oriana Mansutti, Thomas Bretz, V. Scapin, V. Danielyan, T. Hengstebeck, Manel Errando, J. Zapatero, D. Tescaro, Wolfgang Rhode, N. Otte, Felicitas Pauss, Mario Meucci, Francesco Longo, W. Wittek, P. Jacon, M. Camara, H. Anderhub, Daniel Ferenc, C. Merck, Daniela Dorner, E. Aliu, M. V. Fonseca, M. Rissi, Riccardo Paoletti, Elina Lindfors, P. Sartori, H. Vankov, David Paneque, Mosè Mariotti, Denis Bastieri, Daniel Mazin, Masahiro Teshima, Dorota Sobczyńska, G. Maneva, C. C. Hsu, Maria Giller, Alvaro Sanchez, R. Schmitt, J. M. Paredes, Antonio Stamerra, R. G. Pegna, Justin Albert, A. Saggion, Karl Mannheim, L. Peruzzo, Tadeusz Wibig, Adrian Biland, Florian Goebel, Markus Gaug, Pol Bordas, R. Firpo, Saverio Lombardi, S. Rügamer, Juan Abel Barrio, C. Baixeras, E. Prandini, M. Garczarczyk, A. Armada, J. Rico, Stefano Ciprini, A. Robert, M. Poller, A. Sillanpää, Petar Temnikov, Julia Becker, K. Berger, S. Commichau, L. S. Stark, Wlodek Bednarek, R. Zanin, R. Mirzoyan, P. Antoranz, I. Britvitch, E. Oña-Wilhelmi, V. Curtef, M. A. Lopez, R. Kosyra, N. Puchades, Robert Wagner, J. Hose, K. Shinozaki, E. Carmona, P. Liebing, Masaaki Hayashida, M. Shayduk, V. Vitale, Jose Luis Contreras, D. Hakobyan, S. Mizobuchi, L. O. Takalo, Juan Cortina, Jose Miguel Miranda, E. Fernandez, A. Raymers, A. De Angelis, E. Domingo-Santamaría, N. Sidro, A. Laille, Marc Ribó, Valentí Bosch-Ramon, E. Lorenz, A. Piccioli, Ashot Chilingarian, O. Kalekin, D. Pascoli, Nicola Galante, T. Jogler, D. Höhne, P. Majumdar, R. de los Reyes, Nicola Turini, R. K. Bock, N. Tonello, Jorge Andres Lopez Lopez, T. Schweizer, Michele Doro, V. Scalzotto, Miriam Lucio Martinez, Igor Oya, Jose Flix, Daniel Kranich, Ll. Font, Kari Nilsson, Jelena Ninkovic, Francesco Dazzi, J. A. Coarasa, M. Fuchs, Massimo Persic, M. Meyer, Abelardo Moralejo, Diego F. Torres, Ciro Bigongiari, M. Pasanen, R. Kritzer, B. De Lotto, H. Bartko, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Raman, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, R. D. L., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, O., Kalekin, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, N., Puchade, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, and J., Zapatero
Subjects: Photon, Astrophysics::High Energy Astrophysical Phenomena, Flux, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Power law, Astronomical observatories, IMAGING CHERENKOV DETECTOR, gamma ray astronomy, Cosmic rays, Raigs gamma, Radiofrequency radiation, Physics, Gamma rays, Astronomy, Sigma, Astronomy and Astrophysics, Active Galactic Nuclei, Light curve, Redshift, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, BL Lacertae objects: individual (PG 1553+113), gamma rays: observations, Electrónica, Física nuclear, Electricidad, Observatoris astronòmics, BL Lac object
Abstract: In 2005 and 2006, the MAGIC telescope observed very high energy gamma-ray emission from the distant BL Lac object PG 1553 + 113. The overall significance of the signal was 8.8 sigma for 18.8 hr of observation time. The light curve shows no significant flux variations on a daily timescale; the flux level during 2005 was, however, significantly higher compared to 2006. The differential energy spectrum between similar to 90 and 500 GeV is well described by a power law with photon index. Gamma = 4.2 +/- 0.3. The combined 2005 and 2006 energy spectrum provides an upper limit of z = 0.74 on the redshift of the object.
Published: 2007

12. Discovery of very high energy gamma-rays from 1ES 1011+496 at z=0.212

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. K. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch-Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, C. Delgado, R. de los Reyes, B. De Lotto, E. Domingo-Santamaría, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernández, R. Firpo, J. Flix, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. J. García-López, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, D. Höhne, J. Hose, C. C. Hsu, P. Jacon, T. Jogler, R. Kosyra, D. Kranich, R. Kritzer, A. Laille, E. Lindfors, S. Lombardi, F. Longo, J. López, M. López, E. Lorenz, P. Majumdar, G. Maneva, K. Mannheim, O. Mansutti, M. Mariotti, M. Martínez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, D. Nieto, K. Nilsson, J. Ninkovic, E. Oña-Wilhelmi, N. Otte, I. Oya, D. Paneque, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, E. Perlman, M. Persic, L. Peruzzo, A. Piccioli, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribó, J. Rico, M. Rissi, A. Robert, S. Rügamer, A. Saggion, T. Saito, A. Sánchez, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpää, D. Sobczynska, A. Stamerra, L. S. Stark, L. Takalo, F. Tavecchio, P. Temnikov, D. Tescaro, M. Teshima, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, F. Zandanel, R. Zanin, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, E., Perlman, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, F., Tavecchio, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: Photon, Absorption spectroscopy, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, quasars: individual (1ES 1011+496), Gamma Rays: Observations, Physics, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, Active Galactic Nuclei, Redshift, Galaxy, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, Electrónica, Física nuclear, Electricidad, BL Lac object, Visible spectrum
Abstract: We report on the discovery of Very High Energy (VHE) gamma-ray emission from the BL Lacertae object 1ES1011+496. The observation was triggered by an optical outburst in March 2007 and the source was observed with the MAGIC telescope from March to May 2007. Observing for 18.7 hr we find an excess of 6.2 sigma with an integrated flux above 200 GeV of (1.58$\pm0.32) 10^{-11}$ photons cm$^{-2}$ s$^{-1}$. The VHE gamma-ray flux is >40% higher than in March-April 2006 (reported elsewhere), indicating that the VHE emission state may be related to the optical emission state. We have also determined the redshift of 1ES1011+496 based on an optical spectrum that reveals the absorption lines of the host galaxy. The redshift of z=0.212 makes 1ES1011+496 the most distant source observed to emit VHE gamma-rays up to date., 4 pages, 6 figures, minor changes to fit the ApJ version
Published: 2007

13. Discovery of very high energy gamma rays from 1ES 1218+30.4

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, M. Asensio, C. Baixeras, J. A. Barrio, M. Bartelt, H. Bartko, D. Bastieri, S. R. Bavikadi, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, E. Bisesi, R. K. Bock, T. Bretz, I. Britvitch, M. Camara, A. Chilingarian, S. Ciprini, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, R. de los Reyes, B. De Lotto, E. Domingo-Santamaría, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernández, R. Firpo, J. Flix, M. V. Fonseca, L. Font, N. Galante, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, D. Höhne, J. Hose, P. Jacon, O. Kalekin, D. Kranich, A. Laille, T. Lenisa, P. Liebing, E. Lindfors, F. Longo, J. López, M. López, E. Lorenz, F. Lucarelli, P. Majumdar, G. Maneva, K. Mannheim, M. Mariotti, M. Martínez, K. Mase, D. Mazin, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, E. Oña-Wilhelmi, R. Orduña, N. Otte, I. Oya, D. Paneque, R. Paoletti, M. Pasanen, D. Pascoli, F. Pauss, N. Pavel, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, M. Poller, E. Prandini, W. Rhode, J. Rico, B. Riegel, M. Rissi, A. Robert, S. Rügamer, A. Saggion, A. Sánchez, P. Sartori, V. Scalzotto, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpää, D. Sobczyńska, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, A. Torres, D. F. Torres, N. Turini, H. Vankov, A. Vardanyan, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, M., Bartelt, H., Bartko, D., Bastieri, S. R., Bavikadi, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, T., Bretz, I., Britvitch, M., Camara, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, P., Jacon, O., Kalekin, D., Kranich, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, W., Rhode, J., Rico, B., Riegel, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, A., Vardanyan, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, and J., Zapatero
Subjects: BL Lacertae objects: individual (1ES 1218+30.4), Gamma Rays: Observations, Astrophysics, 01 natural sciences, Power law, law.invention, Telescope, law, individual (1ES 1218+30.4) [BL Lacertae objects], 0103 physical sciences, Energy spectrum, 010303 astronomy & astrophysics, Cherenkov radiation, Gamma Rays: Observation, Physics, 010308 nuclear & particles physics, Observations [Gamma Rays], Gamma ray, Astronomy, Astronomy and Astrophysics, Redshift, Space and Planetary Science, Electrónica, Física nuclear, Electricidad
Abstract: The MAGIC collaboration has studied the high-frequency-peaked BL Lac object 1ES 1218 + 30.4, at a redshift z = 0.182, using the MAGIC imaging air Cerenkov telescope located on the Canary Island of La Palma. A gamma-ray signal was observed with 6.4 sigma significance. The differential energy spectrum for an energy threshold of 120 GeV can be fitted by a simple power law, yielding F-E = (8.1 +/- 2.1) x 10(-7)[E/(250 GeV)](-3.0 +/- 0.4) TeV-1 F (E) m(-2) s(-1). During the 6 days of observation in 2005 January, no time variability on timescales of days was found within the statistical errors. The observed integral flux above 350 GeV is nearly a factor of 2 below the upper limit reported by the Whipple collaboration in 2003.
Published: 2006

14. Observation of very high energy gamma-ray emission from the active galactic nucleus 1ES 1959+650 using the MAGIC telescope

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, M. Asensio, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, E. Bisesi, R. K. Bock, T. Bretz, I. Britvitch, M. Camara, A. Chilingarian, S. Ciprini, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, V. Danielyan, F. Dazzi, A. . Angelis, R. . los, B. . Lotto, E. Domingo Santamar\ia, D. Dorner, M. Doro, M. Errando, D. Ferenc, E. Fernandez, R. Firpo, J. Flix, M. V. Fonseca, L. Font, N. Galante, M. Garczarczyk, M. Gaug, J. Gebauer, R. Giannitrapani, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, D. H\ohne, J. Hose, P. Jacon, O. Kalekin, D. Kranich, A. Laille, T. Lenisa, P. Liebing, E. Lindfors, J. Lopez, M. Lopez, E. Lorenz, F. Lucarelli, P. Majumdar, G. Maneva, K. Mannheim, M. Mariotti, M. Mart\inez, K. Mase, D. Mazin, C. Merck, M. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, E. O\~na Wilhelmi, R. Ordu\~na, N. Otte, I. Oya, D. Paneque, R. Paoletti, M. Pasanen, D. Pascoli, F. Pauss, N. Pavel, R. Pegna, L. Peruzzo, A. Piccioli, M. Pin, E. Prandini, J. Rico, W. Rhode, B. Riegel, M. Rissi, A. Robert, G. Rossato, S. R\ugamer, A. Saggion, A. Sanchez, P. Sartori, V. Scalzotto, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, N. Sidro, A. Sillanp\a\a, D. Sobczynska, A. Stamerra, L. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, A. Torres, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, J. Zapatero, LONGO, FRANCESCO, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, T., Bretz, I., Britvitch, M., Camara, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, N., Galante, M., Garczarczyk, M., Gaug, J., Gebauer, R., Giannitrapani, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, P., Jacon, O., Kalekin, D., Kranich, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, C., Merck, M., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, L., Peruzzo, A., Piccioli, M., Pin, E., Prandini, J., Rico, W., Rhode, B., Riegel, M., Rissi, A., Robert, G., Rossato, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, and J., Zapatero
Subjects: RADIO-SOURCES, Active galactic nucleus, gamma ray astronomy, IMAGING CHERENKOV DETECTOR, Astrophysics::High Energy Astrophysical Phenomena, galaxies: individual (1ES 1959+650), TEV BLAZAR 1ES-1959+650, ACCELERATION, SENSITIVITY, NEUTRINOS, SPECTRA, OBJECTS, Flux, Astrophysics, Galaxies: Active, Gamma Rays: Observations, MAGIC (telescope), Cherenkov radiation, Physics, Observations [Gamma Rays], Gamma ray, HEGRA, Astronomy and Astrophysics, Light curve, Active [Galaxies], Crab Nebula, Space and Planetary Science, Electrónica, Física nuclear, Electricidad, individual (1ES 1959+650) [galaxies]
Abstract: The MAGIC Cerenkov telescope has observed very high energy (VHE) gamma-ray emission from the active galactic nucleus 1ES 1959+650 during 6 hr in 2004 September and October. The observations were carried out alternating with observations of the Crab Nebula, whose data were used as a reference source for optimizing gamma -ray/hadron separation and for flux comparison. The data analysis shows VHE gamma-ray emission of 1ES 1959+650 with similar to 8 sigma significance, at a time of low activity in both optical and X-ray wavelengths. An integral flux above similar to 180 GeV of about 20% that of the Crab Nebula was obtained. The light curve, sampled over 7 days, shows no significant variations. The differential energy spectrum between 180 GeV and 2 TeV can be fitted with a power-law of index -2.72 +/- 0.14. The spectrum is consistent with the slightly steeper spectrum seen by HEGRA at higher energies, also during periods of low X-ray activity.
Published: 2006

15. Flux upper limit on gamma-ray emission by GRB 050713a from magic telescope observations

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, M. Asensio, C. Baixeras, J. A. Barrio, M. Bartelt, H. Bartko, D. Bastieri, R. Bavikadi, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, E. Bisesi, R. K. Bock, T. Bretz, I. Britvitch, M. Camara, A. Chilingarian, S. Ciprini, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, R. de los Reyes, B. De Lotto, E. Domingo-Santamaría, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernández, R. Firpo, J. Flix, M. V. Fonseca, L. Font, N. Galante, M. Garczarczyk, M. Gaug, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, D. Höhne, J. Hose, P. Jacoń, O. Kalekin, D. Kranich, A. Laille, T. Lenisa, P. Liebing, E. Lindfors, F. Longo, J. López, M. López, E. Lorenz, F. Lucarelli, P. Majumdar, G. Maneva, K. Mannheim, M. Mariotti, M. Martínez, K. Mase, D. Mazin, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, E. Oña-Wilhelmi, R. Orduña, N. Otte, I. Oya, D. Paneque, R. Paoletti, M. Pasanen, D. Pascoli, F. Pauss, N. Pavel, R. Pegna, M. Persic, L. Peruzzo, A. Piccioli, E. Prandini, W. Rhode, J. Rico, B. Riegel, M. Rissi, A. Robert, S. Rügamer, A. Saggion, A. Sánchez, P. Sartori, V. Scalzotto, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. Shore, N. Sidro, A. Sillanpää, D. Sobczyńska, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, A. Torres, D. F. Torres, N. Turini, H. Vankov, A. Vardanyan, V. Vitale, R. M. Wagner, T. Wibig, W. Wittek, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, M., Bartelt, H., Bartko, D., Bastieri, R., Bavikadi, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, T., Bretz, I., Britvitch, M., Camara, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, P., Jacon, O., Kalekin, D., Kranich, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, W., Rhode, J., Rico, B., Riegel, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, A., Vardanyan, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, and J., Zapatero
Subjects: Physics, Twilight, Observation [Gamma Rays], Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Gamma Rays: Bursts, Gamma Rays: Observations, Gamma ray, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Very High Energy Gamma-ray Astronomy, Redshift, Space and Planetary Science, Electrónica, Física nuclear, MAGIC (telescope), Burst [Gamma Rays], Electricidad, Gamma-ray burst
Abstract: The long-duration GRB050713a was observed by the MAGIC Telescope, 40 seconds after the burst onset, and followed up for 37 minutes, until twilight. The observation, triggered by a SWIFT alert, covered energies above ~175 GeV. Using standard MAGIC analysis, no evidence for a gamma signal was found. As the redshift of the GRB was not measured directly, the flux upper limit, estimated by MAGIC, is still compatible with the assumption of an unbroken power-law spectrum extending from a few hundred keV to our energy range., Comment: 14 pages, 4 figures, submitted to ApJ
Published: 2006

16. MAGIC observations of very high energy gamma-rays from HESS J1813-178

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, A. Armada, M. Asensio, C. Baixeras, J. A. Barrio, M. Bartel, H. Bartko, D. Bastieri, R. Bavikadi, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, E. Bisesi, O. Blanch, R. K. Bock, T. Bretz, I. Britvitch, M. Camara, A. Chilingarian, S. Ciprini, J. A. Coarasa, S. Commichau, J. L. Contreras, J. Cortina, V. Curtev, V. Danielyan, F. Dazzi, A. De Angelis, R. de los Reyes, B. De Lotto, E. Domingo-Santamaria, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernández, R. Firpo, J. Flix, M. V. Fonseca, L. Font, N. Galante, M. Garczarczyk, M. Gaug, J. Gebauer, M. Giller, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, D. Höhne, J. Hose, P. Jacon, O. Kalekin, D. Kranich, A. Laille, T. Lenisa, P. Liebing, E. Lindfors, F. Longo, M. López, J. López, E. Lorenz, F. Lucarelli, P. Majumdar, G. Maneva, K. Mannheim, M. Mariotti, M. Martínez, K. Mase, D. Mazin, C. Merck, M. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, A. Moralejo, K. Nilsson, E. Oña-Wilhelmi, R. Orduña, N. Otte, I. Oya, D. Paneque, R. Paoletti, M. Pasanen, D. Pascoli, F. Pauss, N. Pavel, R. Pegna, L. Peruzzo, A. Piccioli, E. Prandini, J. Rico, W. Rhode, B. Riegel, M. Rissi, A. Robert, G. Rossato, S. Rügamer, A. Saggion, A. Sanchez, P. Sartori, V. Scalzotto, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. Shore, N. Sidro, A. Sillanpää, D. Sobczynska, A. Stamerra, L. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, N. Tonello, A. Torres, D. F. Torres, N. Turini, H. Vankov, V. Vitale, R. Wagner, T. Wibig, W. Wittek, J. Zapatero, J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, M., Bartel, H., Bartko, D., Bastieri, R., Bavikadi, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, O., Blanch, R. K., Bock, T., Bretz, I., Britvitch, M., Camara, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtev, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, N., Galante, M., Garczarczyk, M., Gaug, J., Gebauer, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, P., Jacon, O., Kalekin, D., Kranich, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, Longo, Francesco, M., Lopez, J., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, C., Merck, M., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, L., Peruzzo, A., Piccioli, E., Prandini, J., Rico, W., Rhode, B., Riegel, M., Rissi, A., Robert, G., Rossato, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R., Wagner, T., Wibig, W., Wittek, and J., Zapatero
Subjects: Astrofísica, High energy, Observation [Gamma Rays], Acceleration of Particles, Gamma Rays: Observations, ISM: Supernova Remnants, FOS: Physical sciences, Astrophysics, Power law, Supernova Remnants [ISM], Coincident, Cosmic rays, Physics, gamma ray astronomy, IMAGING CHERENKOV DETECTOR, Astrophysics (astro-ph), Magic (programming), Gamma ray, Astronomy and Astrophysics, Galactic plane, Space and Planetary Science, Acceleration of Particle, Electrónica, Física nuclear, Electricidad, acceleration of particles
Abstract: Recently, the HESS collaboration has reported the detection of gamma-ray emission above a few hundred GeV from eight new sources located close to the Galactic Plane. The source HESS J1813-178 has sparked particular interest, as subsequent radio observations imply an association with SNR G12.82-0.02. Triggered by the detection in VHE gamma-rays, a positionally coincident source has also been found in INTEGRAL and ASCA data. In this Letter we present MAGIC observations of HESS J1813-178, resulting in the detection of a differential gamma-ray flux consistent with a hard-slope power law, described as dN/(dA dt dE) = (3.3+/-0.5)*10^{-12} (E/TeV)^{-2.1+/-0.2} cm^(-2)s^(-1)TeV^(-1). We briefly discuss the observational technique used, the procedure implemented for the data analysis, and put this detection in the perspective of multifrequency observations., Accepted by ApJ Letters
Published: 2006

17. Upper limit for gamma-ray emission above 140 GeV from the dwarf spheroidal galaxy Draco

Author: J. Albert, E. Aliu, H. Anderhub, P. Antoranz, M. Backes, C. Baixeras, J. A. Barrio, H. Bartko, D. Bastieri, J. K. Becker, W. Bednarek, K. Berger, C. Bigongiari, A. Biland, R. K. Bock, P. Bordas, V. Bosch‐Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, V. Curtef, V. Danielyan, F. Dazzi, A. De Angelis, C. Delgado, R. de los Reyes, B. De Lotto, M. De Maria, F. De Sabata, D. Dorner, M. Doro, M. Errando, M. Fagiolini, D. Ferenc, E. Fernández, R. Firpo, M. V. Fonseca, L. Font, M. Fuchs, N. Galante, R. J. García‐López, M. Garczarczyk, M. Gaug, F. Goebel, D. Hakobyan, M. Hayashida, T. Hengstebeck, A. Herrero, D. Höhne, J. Hose, S. Huber, C. C. Hsu, P. Jacon, T. Jogler, R. Kosyra, D. Kranich, A. Laille, E. Lindfors, S. Lombardi, F. Longo, M. López, E. Lorenz, P. Majumdar, G. Maneva, N. Mankuzhiyil, K. Mannheim, M. Mariotti, M. Martínez, D. Mazin, C. Merck, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, S. Mizobuchi, M. Moles, A. Moralejo, D. Nieto, K. Nilsson, J. Ninkovic, E. Oña‐Wilhelmi, N. Otte, I. Oya, M. Panniello, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. Pegna, M. A. Pérez‐Torres, M. Persic, L. Peruzzo, A. Piccioli, F. Prada, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribó, J. Rico, M. Rissi, A. Robert, S. Rügamer, A. Saggion, T. Y. Saito, A. Sánchez, M. Sánchez‐Conde, P. Sartori, V. Scalzotto, V. Scapin, R. Schmitt, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sillanpää, D. Sobczynska, F. Spanier, A. Stamerra, L. S. Stark, L. Takalo, P. Temnikov, D. Tescaro, M. Teshima, D. F. Torres, N. Turini, H. Vankov, A. Venturini, V. Vitale, R. M. Wagner, W. Wittek, F. Zandanel, R. Zanin, and J. Zapatero
Subjects: Photon, galaxies: individual: draco, Astrophysics::High Energy Astrophysical Phenomena, Raigs còsmics, Dark matter, Flux, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Parameter space, dark matter, galaxies: individual (Draco), Cosmic rays, Physics, Cosmology: Dark Matter, galaxies: dwarf, gamma rays: observations, Annihilation, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, Galaxies, Dwarf spheroidal galaxy, Galàxies, Space and Planetary Science, Dark matter (Astronomy), Neutralino, Electrónica, Física nuclear, dark matter, galaxies: dwarf, galaxies: individual (Draco), gamma rays: observations, Matèria fosca (Astronomia), Electricidad
Abstract: The nearby dwarf spheroidal galaxy Draco with its high mass to light ratio is one of the most auspicious targets for indirect dark matter searches. Annihilation of hypothetical DM particles can result in high-energy gamma-rays, e.g. from neutralino annihilation in the supersymmetric framework. With the MAGIC telescope a search for a possible DM signal originating from Draco was performed during 2007. The analysis of the data results in a flux upper limit of 1.1x10^-11 photons cm^-2 sec^-1 for photon energies above 140 GeV, assuming a point like source. Furthermore, a comparison with predictions from supersymmetric models is given. While our results do not constrain the mSUGRA phase parameter space, a very high flux enhancement can be ruled out., Comment: Accepted for publication by Astrophysical Journal
Published: 2008

18. Implementation of the Random Forest method for the Imaging Atmospheric Cherenkov Telescope MAGIC

Author: A. Laille, M. Pasanen, R. de los Reyes, A. Armada, Nicola Turini, Manel Errando, M. Rissi, I. Britvitch, D. Kranich, A. Robert, J. Rico, Francesco Longo, W. Wittek, Jelena Ninkovic, L. Peruzzo, Florian Goebel, Daniela Dorner, H. Anderhub, M. I. Martínez, N. Sidro, Francesco Dazzi, M. Shayduk, R. Kritzer, D. Pascoli, A. Sillanpää, T. Schweizer, Riccardo Paoletti, A. Herrero, K. Shinozaki, Takashi Saito, P. Jacon, Mosè Mariotti, Masaaki Hayashida, A. Venturini, R. Kosyra, Robert Wagner, E. Fernandez, Jose Luis Contreras, G. Maneva, J. M. Paredes, Antonio Stamerra, A. Raymers, T. Jogler, V. Danielyan, D. Tescaro, B. De Lotto, Masahiro Teshima, Tadeusz Wibig, J. Hose, A. Saggion, Juan Cortina, D. Höhne, A. De Angelis, R. J. García-López, Adrian Biland, Petar Temnikov, A. Piccioli, Markus Gaug, R. Firpo, Nicola Galante, Daniel Ferenc, R. Pegna, H. Vankov, P. Majumdar, Julia Becker, S. Commichau, L. S. Stark, F. Pauss, H. Bartko, Roberta Zanin, Michele Doro, Stefano Ciprini, Daniel Nieto, P. Sartori, P. Antoranz, Jose Miguel Miranda, K. Nilsson, T. Hengstebeck, Saverio Lombardi, V. Vitale, C. Delgado, Denis Bastieri, K. Berger, E. Domingo-Santamaría, C. Baixeras, Valentí Bosch-Ramon, Alvaro Sanchez, Diego F. Torres, Ciro Bigongiari, E. Lorenz, V. Scapin, Maria Giller, M. Asensio, V. Curtef, E. Carmona, Felix Spanier, R. Schmitt, Jorge Andres Lopez Lopez, Mario Meucci, W. Bednarek, Jose Flix, V. Scalzotto, Abelardo Moralejo, L. O. Takalo, Ll. Font, M. V. Fonseca, Dorota Sobczyńska, F. Zandanel, Justin Albert, N. Otte, D. Hakobyan, S. Mizobuchi, Marc Ribó, M. T. Costado, R. K. Bock, Pol Bordas, K. Mannheim, Elisa Prandini, M. Meyer, M. Garczarczyk, C. C. Hsu, Ashot Chilingarian, Thomas Bretz, S. N. Shore, Michela Fagiolini, R. Mirzoyan, M. Panniello, M. Fuchs, Massimo Persic, J. Zapatero, Wolfgang Rhode, J. A. Coarasa, I. Oya, M. Camara, C. Merck, E. Aliu, E. Oña-Wilhelmi, N. Puchades, Elina Lindfors, Daniel Mazin, S. Rügamer, M. López, Juan Abel Barrio, and S. Huber
Subjects: Nuclear and High Energy Physics, Astrophysics::High Energy Astrophysical Phenomena, Decision tree, FOS: Physical sciences, Astrophysics, law.invention, Nuclear physics, Telescope, law, GAMMA-RAY, SEPARATION, RADIATION, Instrumentation, Cherenkov radiation, Remote sensing, Physics, COSMIC cancer database, Astrophysics (astro-ph), Magic (programming), Gamma-ray astronomy, Random forest, Data analysis, Electrónica, Física nuclear, gamma ray astronomy, Electricidad
Abstract: The paper describes an application of the tree classification method Random Forest (RF), as used in the analysis of data from the ground-based gamma telescope MAGIC. In such telescopes, cosmic gamma-rays are observed and have to be discriminated against a dominating background of hadronic cosmic-ray particles. We describe the application of RF for this gamma/hadron separation. The RF method often shows superior performance in comparison with traditional semi-empirical techniques. Critical issues of the method and its implementation are discussed. An application of the RF method for estimation of a continuous parameter from related variables, rather than discrete classes, is also discussed., Comment: 16 pages, 8 figures
Published: 2008

19. Variable very-high-energy gamma-ray emission from the microquasar LS I +61 303

Author: S. Lombardi, M. Rissi, Abelardo Moralejo, C. C. Hsu, F. Pauss, D. Kranich, J. Hose, Petar Temnikov, Stefano Ciprini, K. Mannheim, M. Meyer, M. Garczarczyk, Steven N. Shore, W. Bednarek, H. Bartko, Francesco Longo, W. Wittek, A. Sillanpää, Masaaki Hayashida, Manel Errando, Jose Flix, Ll. Font, Jose Luis Contreras, Juan Abel Barrio, Michela Fagiolini, Oriana Mansutti, P. Antoranz, K. Nilsson, M. Laatiaoui, Daniel Ferenc, V. Danielyan, Michele Doro, Juan Cortina, H. Vankov, R. Orduña, P. Majumdar, V. Scapin, R. Pegna, E. Oña-Wilhelmi, Valentí Bosch-Ramon, Paula Gina Isar, M. Shayduk, David Paneque, Thomas Bretz, Josep M. Paredes, A. Raymers, D. Tescaro, Tadeusz Wibig, R. Mirzoyan, E. Lorenz, L. Peruzzo, M. Bartelt, Florian Goebel, Maria Giller, A. De Angelis, A. Piccioli, D. Hakobyan, N. Otte, B. De Lotto, S. Mizobuchi, Nicola Galante, M. Poller, B. Riegel, Wolfgang Rhode, J. Rico, E. Carmona, Francesco Dazzi, Gustavo E. Romero, N. Tonello, D. Pascoli, M. Camara, N. Pavel, K. Berger, A. Armada, R. Kosyra, Robert Wagner, D. Höhne, Marc Ribó, J. Zapatero, T. Schweizer, A. Torres, K. Mase, P. Jacon, I. Oya, M. Asensio, V. Vitale, C. Merck, R. K. Bock, I. Britvitch, G. Maneva, R. Schmitt, Dorota Sobczyńska, A. Saggion, V. Scalzotto, Justin Albert, Diego F. Torres, Ciro Bigongiari, Adrian Biland, C. Baixeras, H. Anderhub, Mario Meucci, Masahiro Teshima, Markus Gaug, K. Shinozaki, E. Aliu, Elina Lindfors, A. Laille, F. Lucarelli, Daniel Mazin, L. S. Stark, M. Pasanen, S. Rügamer, A. Robert, P. Sartori, E. Domingo-Santamaría, R. de los Reyes, M. López, T. Lenisa, Nicola Turini, M. V. Fonseca, Denis Bastieri, M. I. Martínez, S. R. Bavikadi, Alvaro Sanchez, N. Sidro, R. Zanin, T. Hengstebeck, Pol Bordas, M. Fuchs, Massimo Persic, Josue J. Lopez, J. A. Coarasa, Riccardo Paoletti, P. Liebing, Antonio Stamerra, Elisa Prandini, E. Fernandez, Ashot Chilingarian, O. Kalekin, R. Firpo, Guy G. Pooley, E. Bisesi, S. Commichau, Jose Miguel Miranda, V. Curtef, L. O. Takalo, Mosè Mariotti, Daniela Dorner, Universitat de Barcelona, Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Asensio, M., Baixeras, C., Barrio, J. A., Bartelt, M., Bartko, H., Bastieri, D., Bavikadi, S. R., Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bisesi, E., Bock, R. K., Bordas, P., Bosch Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Curtef, V., Danielyan, V., Dazzi, F., De Angelis, A., de los Reyes, R., De Lotto, B., Domingo Santamaría, E., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Ferenc, D., Fernández, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Höhne, D., Hose, J., Hsu, C. C., Isar, P. G., Jacon, P., Kalekin, O., Kosyra, R., Kranich, D., Laatiaoui, M., Laille, A., Lenisa, T., Liebing, P., Lindfors, E., Lombardi, S., Longo, Francesco, López, J., López, M., Lorenz, E., Lucarelli, F., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, M., Martínez, M., Mase, K., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Oña Wilhelmi, E., Orduña, R., Otte, N., Oya, I., Paneque, D., Paoletti, R., Paredes, J. M., Pasanen, M., Pascoli, D., Pauss, F., Pavel, N., Pegna, R., Persic, M., Peruzzo, L., Piccioli, A., Poller, M., Pooley, G., Prandini, E., Raymers, A., Rhode, W., Ribó, M., Rico, J., Riegel, B., Rissi, M., Robert, A., Romero, G. E., Rügamer, S., Saggion, A., Sánchez, A., Sartori, P., Scalzotto, V., Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpää, A., Sobczynska, D., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, A., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zanin, R., and Zapatero, J.
Subjects: Astrofísica, Ciencias Físicas, Raigs còsmics, orbital cycles, VHE Gamma ray, ATMOSPHERIC CHERENKOV TELESCOPE, Microquasar, QUASAR, Estels binaris, Astrophysics, LS I +61 303 (microcuásar), purl.org/becyt/ford/1 [https], Astrophysical jet, Microquasars, Jets (Astrofísica), Gamma ray astronomy, Radio astronomy, Absorption (electromagnetic radiation), Very High-energy Gamma-rays, Cherenkov tekescopes, Physics, Multidisciplinary, Astrophysics (astro-ph), Gamma ray, Radioastronomia, Electrónica, Física nuclear, Electricidad, CIENCIAS NATURALES Y EXACTAS, Astrophysics::High Energy Astrophysical Phenomena, Very High-energy Gamma-ray, Phase (waves), FOS: Physical sciences, microquasars, Cosmic ray, Astrophysics::Cosmology and Extragalactic Astrophysics, Binary stars, Double stars, Binary star, Astronomia de raigs gamma, Quasars, Cosmic rays, Quàsars, Astrophysics::Galaxy Astrophysics, Astronomy, Quasar, purl.org/becyt/ford/1.3 [https], gamma-ray emission, Astrophysical jets, Astronomía, Stars
Abstract: Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes., La lista completa de autores que integran el documento puede consultarse en el archivo., Facultad de Ciencias Astronómicas y Geofísicas, Instituto Argentino de Radioastronomía
Published: 2006

20. The ATLAS hadronic Tile Calorimeter: From construction toward physics

Author: Adragna, P. Cavasinni, V. Costanzo, D. del Prete, T. Dotti, A. Flaminio, V. Lupi, A. Mazzoni, E. Roda, C. Sarri, F. Usai, G. Vivarelli, I. Alexa, C. Boldea, V. Constantinescu, S. Dita, S. Pantea, D. Anderson, K. Farbin, A. Gupta, A. Hurwitz, M. Merritt, F. Oreglia, M. Pilcher, J. Sanders, H. Shochet, M. Tang, F. Teuscher, R. Antonaki, A. Fassouliotis, D. Giakoumopoulou, V. Giokaris, N. Lembesi, M. Manousakis, A. Batusov, V. Budagov, J. Liablin, M. Lomakin, Y. Maliukov, S. Minashvili, I. Romanov, V. Russakovich, N. Sissakian, A. Topilin, N. Vinogradov, V. Bednar, P. Fedorko, I. Sykora, I. Tokar, S. Zenis, T. Biscarat, C. Calvet, D. Ferdi, C. Garde, V. Gris, P. Guicheney, C. Lefevre, R. Montarou, G. Pallin, D. Podlyski, F. Rosnet, P. Roy, P. Santoni, C. Says, L.-P. Vazeille, F. Blanchot, G. Bosman, M. Cavalli-Sforza, M. Korolkov, I. Miralles, L. Norniella, O. Portell, X. Saltó, O. Volpi, M. Bogush, A. Gilewsky, V. Kurochkin, Y. Satsunkevitch, I. Bohm, C. Holmgren, S. Jon-And, K. Klereborn, J. Ramstedt, M. Selldèn, B. Bromberg, C. Huston, J. Miller, R. Richards, R. Caloba, L. Cerqueira, A.S. Damazio, D.O. Maidantchik, C. Marroquim, F. Seixas, J.M. da Silva, P. Carvalho, J. Pinhão, J. Castelo, J. Castillo, M.V. Cuenca, C. Ferrer, A. Fullana, E. Gonzalez, V. Higon, E. Iglesias, C. Lopez Amengual, J.M. Poveda, J. Salvachua, B. Sanchis, E. Torres, J. Valls, J.A. Cobal, M. di Girolamo, B. Efthymiopoulos, I. Gildemeister, O. Grenier, P. Henriques, A. Martin, F. Nessi, M. Schlager, G. Spanó, F. Cogswell, F. Downing, R. Errede, D. Errede, S. Haney, M. Junk, T. Simaitis, V. Vichou, I. David, M. Gomes, A. Maio, A. Marques, C. Pina, J. Saraiva, J.G. Silva, J. Santos, J. Davidek, T. Dolejsi, J. Dolezal, Z. Krivkova, P. Leitner, R. Suk, M. Tas, P. Valkar, S. De, K. Li, J. Sosebee, M. Vartapetian, A. White, A. Fenyuk, A. Karyukhin, A. Miagkov, A. Solodkov, A. Solovianov, O. Starchenko, E. Zaitsev, A. Zenine, A. Guarino, V. le Compte, T. Nodulman, L. Price, L.E. Proudfoot, J. Schlereth, J. Stanek, R. Underwood, D. Hakobyan, H. Simonyan, M. Khubua, J. Kulchitsky, Y. Kuzhir, P. Rumiantsau, V. Shevtsov, P. Starovoitov, P. Lokajicek, M. Nemecek, S. Pribyl, L. Onofre, A.
Subjects: Physics::Instrumentation and Detectors, High Energy Physics::Experiment
Abstract: The Tile Calorimeter, which constitutes the central section of the ATLAS hadronic calorimeter, is a non-compensating sampling device made of iron and scintillating tiles. The construction phase of the calorimeter is nearly complete, and most of the effort now is directed toward the final assembly and commissioning in the underground experimental hall. The layout of the calorimeter and the tasks carried out during construction are described, first with a brief reminder of the requirements that drove the calorimeter design. During the last few years a comprehensive test-beam program has been followed in order to establish the calorimeter electromagnetic energy scale, to study its uniformity, and to compare real data to Monte Carlo simulation. The test-beam setup and first results from the data are described. During the test-beam period in 2004, lasting several months, data have been acquired with a complete slice of the central ATLAS calorimeter. The data collected in the test-beam are crucial in order to study algorithms for hadronic energy reconstruction using single particles. The generalization of these algorithms to reconstruct jet energies will be the starting point for numerous physics studies in which jets play a leading role. The results obtained in applying these algorithms to simulated di-jet events are given in the last section of the note. © 2006 IEEE.
Published: 2006

21. Observations of Markarian 421 with the MAGIC Telescope

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Asensio, M., Baixeras, C., Barrio, J. A., Bartko, H., Bastieri, D., Becker, J., Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bock, R. K., Bordas, P., Bosch-Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Curtef, V., Danielyan, V., Dazzi, F., De Angelis, A., De Los Reyes, R., De Lotto, B., Domingo-Santamaría, E., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Ferenc, D., Fernández, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Höhne, D., Hose, J., Hsu, C. C., Jacon, P., Jogler, T., Kalekin, O., Kosyra, R., Kranich, D., Kritzer, R., Laatiaoui, M., Laille, A., Liebing, P., Lindfors, E., Lombardi, S., Longo, F., López, J., López, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, M., Martínez, M., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Ninkovic, J., Oña-Wilhelmi, E., Orduña, R., Otte, N., Oya, I., Paneque, D., Paoletti, R., Paredes, J. M., Pasanen, M., Pascoli, D., Pauss, F., Pegna, R., Persic, M., Peruzzo, L., Piccioli, A., Poller, M., Prandini, E., Raymers, A., Rhode, W., Ribó, M., Rico, J., Rissi, M., Robert, A., Rügamer, S., Saggion, A., Sánchez, A., Sartori, P., Scalzotto, V., Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpää, A., Sobczynska, D., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, A., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, O., Kalekin, R., Kosyra, D., Kranich, R., Kritzer, M., Laatiaoui, A., Laille, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Mart\inez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, and J., Zapatero
Subjects: Astrophysics::High Energy Astrophysical Phenomena, EXTRAGALACTIC BACKGROUND LIGHT, ACTIVE GALAXY MARKARIAN-421, TEV BLAZAR MARKARIAN-421, SPITZER-SPACE-TELESCOPE, DIFFUSE INFRARED LIGHT, HIGH-ENERGY PHOTONS, COBE DIRBE MAPS, BL-LAC OBJECTS, 1ST DETECTIONS, GAMMA-RAYS, Astrophysics, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, Power law, individual (Markarian 421) [BL Lacertae objects], law.invention, law, Blazar, Physics, Attenuation, BL Lacertae Objects: Individual: Name: Markarian 421 [Galaxies], observations [gamma rays], Quiescent state, Astronomy and Astrophysics, Synchrotron, Galaxies: BL Lacertae Objects: Individual: Name: Markarian 421, Extragalactic background light, Space and Planetary Science, Data analysis, Spectral energy distribution, Electrónica, Física nuclear, Gamma Rays: Observations, Electricidad
Abstract: The MAGIC telescope took data of very high energy ?-ray emission from the blazar Markarian 421 (Mrk 421) between 2004 November and 2005 April. We present a combined analysis of data samples recorded under different observational conditions, down to ?-ray energies of 100 GeV. The flux was found to vary between 0.5 and 2 crab (integrated above 200 GeV), considered a low state when compared to known data. Although the flux varied day by day, no short-term variability was observed, although there is some indication that not all nights show an equally quiescent state. The results at higher energies were found to be consistent with previous observations. A clear correlation is observed between ?-ray and X-ray fluxes, whereas no significant correlation between ?-ray and optical data is seen. The spectral energy distribution between 100 GeV and 3 TeV shows a clear deviation from a power law, more clearly and at lower flux than previous observations at higher energies. The deviation persists after correcting for the effect of attenuation by the extragalactic background light, and most likely is source-inherent. There is a rather clear indication of an inverse Compton peak around 100 GeV. The spectral energy distribution of Mrk 421 can be fitted by a one-zone synchrotron self-Compton model, suggesting once again a leptonic origin of the very high energy ?-ray emission from this blazar. ispartof: Astrophysical Journal vol:663 issue:1 pages:125-138 status: published
Published: 2007
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22. Discovery of Very High Energy γ-Rays from Markarian 180 Triggered by an Optical Outburst

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Asensio, M., Baixeras, C., Barrio, J. A., Bartelt, M., Bartko, H., Bastieri, Denis, Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bisesi, E., Bock, R. K., Bordas, P., BOSCH RAMON, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Curtef, V., Danielyan, V., Dazzi, Francesco, DE ANGELIS, A., DE LOS REYES, R., DE LOTTO, B., DOMINGO SANTAMARIA, E., Dorner, D., Doro, Michele, Errando, M., Fagiolini, M., Ferenc, D., Fernandez, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Hohne, D., Hose, J., Hsu, C. C., Isar, P. G., Jacon, P., Kalekin, O., Kosyra, R., Kranich, D., Laatiaoui, M., Laille, A., Lenisa, T., Liebing, P., Lindfors, E., Lombardi, Saverio, Longo, F., Lopez, J., Lopez, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, Mose', Martinez, M., Mase, K., Daniel, Mazin, Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Ninkovic, J., ONA WILHELMI, E., Orduna, R., Otte, N., Oya, I., Paneque, D., Paoletti, R., Paredes, J. M., Pasanen, M., Pascoli, Donatella, Pauss, F., Pavel, N., Pegna, R., Persic, M., Peruzzo, Luigi, Piccioli, A., Poller, M., Prandini, Elisa, Raymers, A., Rhode, W., Ribo, M., Rico, J., Riegel, B., Rissi, M., Robert, A., Rugamer, S., Saggion, Antonio, Sanchez, A., Sartori, Paolo, Scalzotto, VILLI MARIO, Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpaa, A., Sobczynska, D., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, A., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, C. C., Hsu, P., Jacon, O., Kalekin, R., Kosyra, D., Kranich, M., Laatiaoui, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Mart\inez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, B., Riegel, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, and J., Zapatero
Subjects: BL Lacertae objects : individual (Markarian 180), High energy, Photon, Astrophysics::High Energy Astrophysical Phenomena, individual (Markarian 180) [BL Lacertae objects], Flux, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Raigs gamma, Observacions astronòmiques, Target of opportunity, gamma rays : observations, BL Lacertae Objects: Individual: Name: Markarian 180 [Galaxies], Cosmic rays, Astrophysics::Galaxy Astrophysics, Galaxies: BL Lacertae Objects: Individual: Name: Markarian 180, Gamma Rays: Observations, Physics, gamma ray astronomy, IMAGING CHERENKOV DETECTOR, Observations [Gamma Rays], Gamma rays, Gamma ray, Astronomy and Astrophysics, Crab Nebula, Space and Planetary Science, Electrónica, Física nuclear, Astrophysics::Earth and Planetary Astrophysics, Electricidad, Astronomical observations, BL Lac object
Abstract: The high-frequency-peaked BL Lacertae object Markarian~180 (Mrk~180) was observed to have an optical outburst in 2006 March, triggering a Target of Opportunity observation with the MAGIC telescope. The source was observed for 12.4 hr and very high energy $\gamma$-ray emission was detected with a significance of 5.5 $\sigma$. An integral flux above 200 GeV of $(2.3\pm0.7)\times10^{-11} {cm}^{-2} {s}^{-1}$ was measured, corresponding to 11% of the Crab Nebula flux. A rather soft spectrum with a photon index of $-3.3\pm0.7$ has been determined. No significant flux variation was found., Comment: Accepted by ApJ Letters, minor revisions
Published: 2006
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23. MAGIC observations of PG 1553+113 during a multiwavelength campaign in July 2006

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Baixeras, C., Barrio, J. A., Bartko, H., Bastieri, D., Becker, J. K., Bednarek, W., Berdyugin, A., Berger, K., Bigongiari, C., Biland, A., Bock, R. K., Bordas, P., Bosch Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Commichau, S., Contreras, J. L., Cortina, J., Costado, M. T., Curtef, V., Danielyan, V., Dazzi, F., Angelis, A. D., Delgado, C., Reyes, R. D., Lotto, B. D., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Ferenc, D., Fernandez, E., Firpo, R., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garcia Lopez, R. J., Garczarczyk, M., Gaug, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Herrero, A., Hohne, D., Hose, J., Hsu, C. C., Huber, S., Jacon, P., Jogler, T., Kosyra, R., Kranich, D., Kritzer, R., Laille, A., Lindfors, E., Lombardi, S., Longo, Francesco, Lopez, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mariotti, M., Martinez, M., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nieto, D., Nilsson, K., Ninkovic, J., Ona Wilhelmi, E., Otte, N., Oya, I., Panniello, M., Paoletti, R., Pasanen, M., Pascoli, D., Pauss, F., Pegna, R., Persic, M., Peruzzo, L., Piccioli, A., Prandini, E., Puchades, N., Raymers, A., Rico, J., Rhode, W., Rissi, M., Robert, A., Rugamer, S., Saggion, A., Saito, T. Y., Sanchez, A., Sartori, P., Scalzotto, V., Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpaa, A., Sobczynska, D., Spanier, F., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Torres, D. F., Turini, N., Vankov, H., Venturini, A., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zandanel, F., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, A., Berdyugin, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D., Reye, B. D., Lotto, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, S., Huber, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, M., Panniello, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, N., Puchade, A., Raymer, J., Rico, W., Rhode, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T. Y., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, F., Spanier, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, A., Venturini, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: Active galactic nucleus, TELESCOPE, FOS: Physical sciences, Flux, Astrophysics, REDSHIFTS, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, Power law, Energy spectrum, MAGIC (telescope), PG-1553+113, Physics, Spectral index, SPECTROSCOPY, Astrophysics (astro-ph), Active Galactic Nuclei, Astronomy and Astrophysics, BL LACERTAE OBJECTS, MAGIC telescope, Very High Energy Gamma-ray Astronomy, Space and Planetary Science, Electrónica, Física nuclear, Atmospheric absorption, Electricidad
Abstract: The active galactic nucleus PG 1553+113 was observed by the MAGIC telescope in July 2006 during a multiwavelength campaign, in which telescopes in the optical, X-ray, and very high energies participated. Although the MAGIC data were affected by strong atmospheric absorption (calima), they were analyzed after applying a correction. In 8.5 hours, a signal was detected with a significance of 5.0 sigma. The integral flux above 150 GeV was (2.6 +/- 0.9)*10^{-7} ph/s/m^2. By fitting the differential energy spectrum with a power law, a spectral index of -4.1 +/- 0.3 was obtained., 4 pages, 3 figures, accepted for publication in A&A
Published: 2008
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24. First bounds on the very high energy γ-ray emission from Arp 220

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Baixeras, C., Barrio, J. A., Bartko, H., Bastieri, D., Becker, J., Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bock, R. K., Bordas, P., Bosch Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Curtef, V., Danielyan, V., Dazzi, F., Angelis, A. D., Los, R. D., Lotto, B. D., Domingo Santamaria, E., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Ferenc, D., Fernandez, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Hohne, D., Hose, J., Hsu, C. C., Jacon, P., Jogler, T., Kalekin, O., Kosyra, R., Kranich, D., Kritzer, R., Laille, A., Liebing, P., Lindfors, E., Lombardi, S., Longo, F., Lopez, J., Lopez, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, M., Martinez, M., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Ninkovic, J., Ona Wilhelmi, E., Otte, N., Oya, I., Paneque, D., Paoletti, Riccardo, Paredes, J. M., Pasanen, M., Pascoli, D., Pauss, F., Pegna, R., Persic, M., Peruzzo, L., Piccioli, A., Poller, M., Puchades, N., Prandini, E., Raymers, A., Rhode, W., Ribo, M., Rico, J., Rissi, M., Robert, A., Rugamer, S., Saggion, A., Sanchez, A., Sartori, P., Scalzotto, V., Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpaa, A., Sobczynska, D., Stamerra, Antonio, Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, R. D., Los Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, O., Kalekin, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, N., Puchade, E., Prandini, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, J., Zapatero, and Universitat de Barcelona
Subjects: ULTRALUMINOUS INFRARED GALAXIES, High energy, Infrared, IMAGES, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, Galaxie, STAR-FORMATION, law.invention, Telescope, Raigs gamma, law, HESS, MAGIC (telescope), Cherenkov radiation, Astrophysics::Galaxy Astrophysics, Physics, Astrophysics (astro-ph), Gamma rays, Gamma ray, MAGIC TELESCOPE, REGIONS, EGRET, Astronomy and Astrophysics, Galaxies, Galaxy, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, Electrónica, Física nuclear, Electricidad
Abstract: Using the Major Atmospheric Gamma Imaging Cherenkov Telescope (MAGIC), we have observed the nearest ultra-luminous infrared galaxy Arp 220 for about 15 hours. No significant signal was detected within the dedicated amount of observation time. The first upper limits to the very high energy $\gamma$-ray flux of Arp 220 are herein reported and compared with theoretical expectations., Comment: Accepted for publication in ApJ
Published: 2007

25. Observation of very high energy gamma-rays from the AGN 1ES 2344+514 in low emission state with the magic telescope

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Baixeras, C., Barrio, J. A., Bartko, H., Bastieri, D., Becker, J. K., Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bock, R. K., Bordas, P., Bosch Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Costado, M. T., Curtef, V., Danielyan, V., Dazzi, F., Angelis, A. D., Delgado, C., Reyes, R. D. L., Lotto, B. D., Domingo Santamaria, E., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Angelis, D., Ferenc, D., Fernandez, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., Garcia Lopez, R., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Herrero, A., Hohne, D., Hose, J., Hsu, C. C., Jacon, P., Jogler, T., Kalekin, O., Kosyra, R., Kranich, D., Kritzer, R., Laille, A., Liebing, P., Lindfors, E., Lombardi, S., Longo, Francesco, Lopez, J., Lopez, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, M., Martinez, M., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Ninkovic, J., Onna Wilhelmi, E., Otte, N., Oya, I., Paneque, D., Panniello, M., Paoletti, R., Paredes, J. M., Pasanen, M., Pascoli, D., Pauss, F., Pegna, R., Persic, M., Peruzzo, L., Piccioli, A., Poller, M., Prandini, E., Puchades, N., Raymers, A., Rhode, W., Ribo, M., Rico, J., Rissi, M., Robert, A., Rugamer, S., Saggion, A., Sanchez, A., Sartori, P., Scalzotto, V., Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpaa, A., Sobczynska, D., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zandanel, F., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D. L., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Angeli, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, O., Kalekin, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, J., Ninkovic, E., Onna Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: ACTIVE GALACTIC NUCLEI, High energy, Photon, Astrophysics::High Energy Astrophysical Phenomena, UNIVERSE, Flux, FOS: Physical sciences, Astrophysics, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, 01 natural sciences, Power law, law.invention, law, 0103 physical sciences, SPECTRA, MAGIC (telescope), 010303 astronomy & astrophysics, MULTIWAVELENGTH OBSERVATIONS, Physics, 010308 nuclear & particles physics, CHERENKOV TELESCOPES, Astrophysics (astro-ph), Gamma ray, HEGRA, EINSTEIN SLEW SURVEY, Astronomy and Astrophysics, Active Galactic Nuclei, BL-LACERTAE OBJECTS, MAGIC telescope, LAC OBJECTS, DISCOVERY, RADIATION, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, Electrónica, Física nuclear, High Energy Physics::Experiment, Electricidad, Flare
Abstract: The MAGIC collaboration has observed very high energy gamma ray emission from the AGN 1ES 2344+514. A gamma-ray signal corresponding to an 11 sigma excess and an integral flux of (2.38+-0.30(stat)+-0.70(syst))*10^-11 cm^-2 s^-1 above 200 GeV has been obtained from 23.1 hours of data taking between 2005 August 3 and 2006 January 1. The data confirm the previously detected gamma-ray emission from this object during a flare seen by the Whipple collaboration in 1995 and the evidence (below 5 sigma significance level) from long-term observations conducted by the Whipple and HEGRA groups. The MAGIC observations show a relatively steep differential photon spectrum that can be described by a power law with a photon index of alpha=-2.95+-0.12(stat)+-0.2(syst) between 140 GeV and 5.4 TeV. The observations reveal a low flux state, about six times below the 1995 flare seen by Whipple and comparable with the previous Whipple and HEGRA long term measurements. During the MAGIC observations no significant time variability has been observed., Comment: 7 pages, 7 figures, ApJ in press; updated fig. 4, fig. 7, tab. 3, removed typo in differential spectra
Published: 2007

26. Constraints on the steady and pulsed very high energy gamma-ray emission from observations of PSR B1951+32/CTB 80 with the magic telescope

Author: Albert, J, Aliu, E, Anderhub, H, Antoranz, P, Armada, A, Baixeras, C, Barrio, Ja, Bartko, H, Bastieri, Denis, Becker, Jk, Bednarek, W, Berger, K, Bigongiari, C, Biland, A, Bock, Rk, Bordas, P, BOSCH RAMON, V, Bretz, T, Britvitch, I, Camara, M, Carmona, E, Chilingarian, A, Coarasa, Ja, Commichau, S, Contreras, Jl, Cortina, J, Costado, Mt, Curtef, V, Danielyan, V, Dazzi, Francesco, DE ANGELIS, A, Delgado, C, Reyes, Rdl, DE LOTTO, B, DOMINGO SANTAMARIA, E, Dorner, D, Doro, Michele, Errando, M, Fagiolini, M, Ferenc, D, Fernandez, E, Firpo, R, Flix, J, Fonseca, Mv, Font, L, Fuchs, M, Galante, N, GARCIA LOPEZ, R, Garczarczyk, M, Gaug, M, Giller, M, Goebel, F, Hakobyan, D, Hayashida, M, Hengstebeck, T, Herrero, A, Hirotani, K, Hne, Dhr, Hose, J, Hsu, Cc, Jacon, P, Jogler, T, Kosyra, R, Kranich, D, Kritzer, R, Laille, A, Lindfors, E, Lombardi, S, Longo, F, Lopez, J, Lopez, M, Lorenz, E, Majumdar, P, Maneva, G, Mannheim, K, Mansutti, O, Mariotti, Mose', Martinez, M, Mazin, D, Merck, C, Meucci, M, Meyer, M, Miranda, Jm, Mirzoyan, R, Mizobuchi, S, Moralejo, A, Nieto, D, Nilsson, K, Ninkovic, J, ONA WILHELMI, E, Otte, N, Oya, I, Paneque, D, Panniello, M, Paoletti, R, Paredes, Jm, Pasanen, M, Pascoli, Donatella, Pauss, F, Pegna, R, Persic, M, Peruzzo, Luigi, Piccioli, A, Poller, M, Prandini, E, Puchades, N, Raymers, A, Rhode, W, Ribo, M, Rico, J, Rissi, M, Robert, A, Gamer, Srr, Saggion, Antonio, Sanchez, A, Sartori, Paolo, Scalzotto, VILLI MARIO, Scapin, V, Schmitt, R, Schweizer, T, Shayduk, M, Shinozaki, K, Shore, Sn, Sidro, N, Sillanpaa, A, Sobczynska, D, Stamerra, A, Stark, Ls, Takalo, L, Temnikov, P, Tescaro, D, Teshima, M, Tonello, N, Torres, Df, Turini, N, Vankov, H, Vitale, V, Wagner, Rm, Wibig, T, Wittek, W, Zandanel, F, Zanin, R, Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R. D. L., Reye, B. D., Lotto, E., Domingo Santamaria, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, K., Hirotani, D. H. R., Hne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, D., Paneque, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S. R. R., Gamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: SUPERNOVA REMNANT CTB-80, CTB80, Very High Energy Gamma-ray Astronomy, Pulsar, Pulsar Wind Nebulae, MAGIC telescope, PSR B1951+32, gamma ray astronomy, Cosmic rays, IMAGING CHERENKOV DETECTOR, RAPIDLY SPINNING PULSARS, CRAB-NEBULA, GAPS, MAGNETOSPHERES, RADIATION, WIND NEBULAE, VELA-X
Abstract: We report on very high energy gamma-ray observations with the MAGIC Telescope of the pulsar PSR B1951+32 and its associated nebula, CTB 80. Our data constrain the cutoff energy of the pulsar to be less than 32 GeV, assuming the pulsed gamma-ray emission to be exponentially cut off. In the case that the cutoff follows a superexponential behavior, the cutoff energy can be as high as similar to 60 GeV. The upper limit on the flux of pulsed gamma-ray emission above 75 GeV is 4.3; 10(-11) photons cm(-2) s(-1), and the upper limit on the flux of steady emission above 140 GeV is 1.5; 10(-11) photons cm(-2) s(-1). We discuss our results in the framework of recent model predictions and other studies.
Published: 2007

27. Very high energy gamma-ray radiation from the stellar mass black hole binary Cygnus X-1

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Baixeras, C., Barrio, J. A., Bartko, H., Bastieri, Denis, Becker, J. K., Bednarek, W., Berger, K., Bigongiari, Ciro, Biland, A., Bock, R. K., Bordas, P., Bosch Ramon, V., Bretz, T., Britvitch, I., Camara, M., Carmona, E., Chilingarian, A., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Costado, M. T., Curtef, V., Danielyan, V., Dazzi, Francesco, De Angelis, A., Delgado, C., de los Reyes, R., De Lotto, B., Domingo Santamaría, E., Dorner, D., Doro, Michele, Errando, M., Fagiolini, M., Ferenc, D., Fernández, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Fuchs, M., Galante, N., García López, R. J., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Herrero, A., Höhne, D., Hose, J., Hsu, C. C., Jacon, P., Jogler, T., Kosyra, R., Kranich, D., Kritzer, R., Laille, A., Lindfors, E., Lombardi, Saverio, Longo, F., López, J., López, M., Lorenz, E., Majumdar, P., Maneva, G., Mannheim, K., Mansutti, O., Mariotti, Mose', Martínez, M., Mazin, D., Merck, C., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nieto, D., Nilsson, K., Ninkovic, J., Oña Wilhelmi, E., Otte, N., Oya, I., Panniello, M., Paoletti, R., Paredes, J. M., Pasanen, M., Pascoli, Donatella, Pauss, F., Pegna, R., Persic, M., Peruzzo, Luigi, Piccioli, A., Prandini, Elisa, Puchades, N., Raymers, A., Rhode, W., Ribó, M., Rico, J., Rissi, M., Robert, A., Rügamer, S., Saggion, Antonio, Saito, T., Sánchez, A., Sartori, Paolo, Scalzotto, VILLI MARIO, Scapin, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpää, A., Sobczynska, D., Stamerra, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Torres, D. F., Turini, N., Vankov, H., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zandanel, F., Zanin, R., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, C., Baixera, J. A., Barrio, H., Bartko, D., Bastieri, J. K., Becker, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, V., Curtef, V., Danielyan, F., Dazzi, A. D., Angeli, C., Delgado, R., Reye, B. D., Lotto, E., Domingo SantamariA, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, R. J., Garcia Lopez, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, A., Herrero, D., Hohne, J., Hose, C. C., Hsu, P., Jacon, T., Jogler, R., Kosyra, D., Kranich, R., Kritzer, A., Laille, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Martinez, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, E., Ona Wilhelmi, N., Otte, I., Oya, M., Panniello, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T., Saito, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanpaa, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, F., Zandanel, R., Zanin, and J., Zapatero
Subjects: Black Holes, Stellar mass, Flux, FOS: Physical sciences, Astrophysics, law.invention, X-ray astronomy, law, Gamma ray astronomy, Astronomia de raigs gamma, Physics, Nebula, Acceleradors de partícules, Astrophysics (astro-ph), Gamma ray, Sigma, Astronomy and Astrophysics, Black Hole, Very High Energy Gamma-ray Astronomy, MAGIC telescope, Particle accelerators, Astronomia de raigs X, Black hole, Crab Nebula, Space and Planetary Science, Electrónica, Física nuclear, Electricidad, Flare
Abstract: We report on the results from the observations in very high energy band (VHE, E_gamma > 100 GeV) of the black hole X-ray binary (BHXB) Cygnus X-1. The observations were performed with the MAGIC telescope, for a total of 40 hours during 26 nights, spanning the period between June and November 2006. Searches for steady gamma-ray signals yielded no positive result and upper limits to the integral flux ranging between 1 and 2% of the Crab nebula flux, depending on the energy, have been established. We also analyzed each observation night independently, obtaining evidence of gamma-ray signals at the 4.0 standard deviations (sigma) significance level (3.2 sigma after trial correction) for 154 minutes effective on-time (EOT) on September 24 between 20h58 and 23h41 UTC, coinciding with an X-ray flare seen by RXTE, Swift and INTEGRAL. A search for faster-varying signals within a night resulted in an excess with a significance of 4.9 sigma (4.1 sigma after trial correction) for 79 minutes EOT between 22h17 and 23h41 UTC. The measured excess is compatible with a point-like source at the position of Cygnus X-1, and excludes the nearby radio nebula powered by its relativistic jet. The differential energy spectrum is well fitted by an unbroken power-law described by dN/(dA dt dE) = (2.3+- 0.6) x 10^{-12} (E/1 TeV)^{-3.2 +- 0.6}. This is the first experimental evidence of VHE emission from a stellar-mass black hole, and therefore from a confirmed accreting X-ray binary., 4 ApJL-formatted pages, 4 figures. Revised version accepted for publication at ApJL (26-06-2007)
Published: 2007

28. Observation of gamma rays from the galactic center with the MAGIC telescope

Author: Albert, J., Aliu, E., Anderhub, H., Antoranz, P., Armada, A., Asensio, M., Baixeras, C., Barrio, J. A., Bartelt, M., Bartko, H., Bastieri, D., Bavikadi, R., Bednarek, W., Berger, K., Bigongiari, C., Biland, A., Bisesi, E., Bock, R. K., Bretz, T., Britvitch, I., Camara, M., Chilingarian, A., Ciprini, S., Coarasa, J. A., Commichau, S., Contreras, J. L., Cortina, J., Curtef, V., Danielyan, V., Dazzi, F., De Angelis, A., de los Reyes, R., De Lotto, B., Domingo Santamaría, E., Dorner, D., Doro, M., Errando, M., Fagiolini, M., Ferenc, D., Fernández, E., Firpo, R., Flix, J., Fonseca, M. V., Font, L., Galante, N., Garczarczyk, M., Gaug, M., Giller, M., Goebel, F., Hakobyan, D., Hayashida, M., Hengstebeck, T., Höhne, D., Hose, J., Jacon, P., Kalekin, O., Kranich, D., Laille, A., Lenisa, T., Liebing, P., Lindfors, E., Longo, F., López, J., López, M., Lorenz, E., Lucarelli, F., Majumdar, P., Maneva, G., Mannheim, K., Mariotti, M., Martínez, M., Mase, K., Mazin, D., Merck, M., Meucci, M., Meyer, M., Miranda, J. M., Mirzoyan, R., Mizobuchi, S., Moralejo, A., Nilsson, K., Oña Wilhelmi, E., Orduña, R., Otte, N., Oya, I., Paneque, D., Paoletti, R., Pasanen, M., Pascoli, D., Pauss, F., Pavel, N., Pegna, R., Peruzzo, L., Piccioli, A., Prandini, E., Rico, J., Rhode, W., Riegel, B., Rissi, M., Robert, A., Rügamer, S., Saggion, A., Sánchez, A., Sartori, P., Scalzotto, V., Schmitt, R., Schweizer, T., Shayduk, M., Shinozaki, K., Shore, S. N., Sidro, N., Sillanpää, A., Sobczynska, D., Stamerra, Antonio, Stepanian, A., Stark, L. S., Takalo, L., Temnikov, P., Tescaro, D., Teshima, M., Tonello, N., Torres, A., Torres, D. F., Turini, Nicola, Vankov, H., Vardanyan, A., Vitale, V., Wagner, R. M., Wibig, T., Wittek, W., Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, M., Bartelt, H., Bartko, D., Bastieri, R., Bavikadi, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, T., Bretz, I., Britvitch, M., Camara, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\ia, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, P., Jacon, O., Kalekin, D., Kranich, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, M., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, L., Peruzzo, A., Piccioli, E., Prandini, J., Rico, W., Rhode, B., Riegel, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, A., Stepanian, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, A., Vardanyan, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, and J., Zapatero
Subjects: Astrofísica, High energy, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astrophysics, Power law, Spectral line, Acceleration of Particles, Galaxy: Center, Gamma Rays: Observations, MAGIC (telescope), Physics, Center [Galaxy], Observations [Gamma Rays], Galactic Center, Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, Space and Planetary Science, Acceleration of Particle, Electrónica, Física nuclear, Electricidad, Energy (signal processing)
Abstract: Recently, the Galactic Center has been reported to be a source of very high energy (VHE) gamma-rays by the VERITAS, CANGAROO and HESS experiments. The energy spectra as measured by these experiments show substantial differences. In this Letter we present MAGIC observations of the Galactic Center, resulting in the detection of a differential gamma-ray flux consistent with a steady, hard-slope power law, described as dN/(dA dt dE) = (2.9+/-0.6)*10^{-12} (E/TeV)^{-2.2+/-0.2} cm^{-2}s^{-1}TeV^{-1}. The gamma-ray source is centered at (Ra, Dec)=(17h 45m 20s, -29deg 2'. This result confirms the previous measurements by the HESS experiment and indicates a steady source of TeV gamma-rays. We briefly describe the observational technique used, the procedure implemented for the data analysis, and discuss the results in the perspective of different models proposed for the acceleration of the VHE gamma-rays., ApJL submitted
Published: 2006

29. Observation of VHE Gamma Radiation from HESS J1834-087/W41 with the MAGIC Telescope

Author: Albert, J, Aliu, E, Anderhub, H, Antoranz, P, Armada, A, Asensio, M, Baixeras, C, Barrio, Ja, Bartelt, M, Bartko, H, Bastieri, D, Bavikadi, Sr, Bednarek, W, Berger, K, Bigongiari, C, Biland, A, Bisesi, E, Bock, Rk, Bordas, P, Bosch Ramon, V, Bretz, T, Britvitch, I, Camara, M, Carmona, E, Chilingarian, A, Ciprini, S, Coarasa, Ja, Commichau, S, Contreras, Jl, Cortina, J, Curtef, V, Dame, Tm, Danielyan, V, Dazzi, F, DE ANGELIS, Alessandro, Reyes, Rdl, DE LOTTO, Barbara, Domingo Santamari, E, Dorner, D, Doro, M, Errando, M, Fagiolini, M, Ferenc, D, Fernandez, E, Firpo, R, Flix, J, Fonseca, Mv, Font, L, Fuchs, M, Galante, N, Garczarczyk, M, Gaug, M, Giller, M, Goebel, F, Hakobyan, D, Hayashida, M, Hengstebeck, T, Hohne, D, Hose, J, Hsu, Cc, Isar, Pg, Jacon, P, Kalekin, O, Kasyra, R, Kranich, D, Laatiaoui, M, Laille, A, Lenisa, T, Liebing, P, Lindfors, E, Lombardi, S, Longo, F, Lopez, J, Lopez, M, Lorenz, E, Lucarelli, F, Majumdar, P, Maneva, G, Mannheim, K, Mansutti, O, Mariotti, M, Martinez, M, Mase, K, Mazin, D, Merck, C, Meucci, M, Meyer, M, Miranda, Jm, Mirzoyan, R, Mizobuchi, S, Moralejo, A, Nilsson, K, Ona Wilhelmi, E, Orduna, R, Otte, N, Oya, I, Paneque, D, Paoletti, R, Paredes, Jm, Pasanen, M, Pascoli, D, Pauss, F, Pavel, N, Pegna, R, Persic, M, Peruzzo, L, Piccioli, A, Poller, M, Prandini, E, Raymers, A, Rico, J, Rhode, W, Ribo, M, Riegel, B, Rissi, M, Robert, A, Rugamer, S, Saggion, A, Sanchez, A, Sartori, P, Scalzotto, V, Scapin, V, Schmitt, R, Schweizer, T, Shayduk, M, Shinozaki, K, Shore, Sn, Sidro, N, Sillanpaa, A, Sobczynska, D, Stamerra, A, Stark, Ls, Takalo, L, Temnikov, P, Tescaro, D, Teshima, M, Tonello, N, Torres, A, Torres, Df, Turini, N, Vankov, H, Vitale, V, Wagner, Rm, Wibig, T, Wittek, W, Zanin, R, Zapatero, J., J., Albert, E., Aliu, H., Anderhub, P., Antoranz, A., Armada, M., Asensio, C., Baixera, J. A., Barrio, M., Bartelt, H., Bartko, D., Bastieri, S. R., Bavikadi, W., Bednarek, K., Berger, C., Bigongiari, A., Biland, E., Bisesi, R. K., Bock, P., Borda, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Ciprini, J. A., Coarasa, S., Commichau, J. L., Contrera, J., Cortina, V., Curtef, T. M., Dame, V., Danielyan, F., Dazzi, Angelis, A., Los, R., Lotto, B., E., Domingo Santamar\i, D., Dorner, M., Doro, M., Errando, M., Fagiolini, D., Ferenc, E., Fernandez, R., Firpo, J., Flix, M. V., Fonseca, L., Font, M., Fuch, N., Galante, M., Garczarczyk, M., Gaug, M., Giller, F., Goebel, D., Hakobyan, M., Hayashida, T., Hengstebeck, D., H\ohne, J., Hose, C. C., Hsu, P. G., Isar, P., Jacon, O., Kalekin, R., Kasyra, D., Kranich, M., Laatiaoui, A., Laille, T., Lenisa, P., Liebing, E., Lindfor, S., Lombardi, Longo, Francesco, J., Lopez, M., Lopez, E., Lorenz, F., Lucarelli, P., Majumdar, G., Maneva, K., Mannheim, O., Mansutti, M., Mariotti, M., Mart\inez, K., Mase, D., Mazin, C., Merck, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, S., Mizobuchi, A., Moralejo, K., Nilsson, E., O\~na Wilhelmi, R., Ordu\~na, N., Otte, I., Oya, D., Paneque, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, N., Pavel, R., Pegna, M., Persic, L., Peruzzo, A., Piccioli, M., Poller, E., Prandini, A., Raymer, J., Rico, W., Rhode, M., Ribo, B., Riegel, M., Rissi, A., Robert, S., R\ugamer, A., Saggion, A., Sanchez, P., Sartori, V., Scalzotto, V., Scapin, R., Schmitt, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sillanp\a\a, D., Sobczynska, A., Stamerra, L. S., Stark, L., Takalo, P., Temnikov, D., Tescaro, M., Teshima, N., Tonello, A., Torre, D. F., Torre, N., Turini, H., Vankov, V., Vitale, R. M., Wagner, T., Wibig, W., Wittek, R., Zanin, and J., Zapatero
Subjects: ISM: cosmic rays, Observation [Gamma Rays], Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Gamma Rays: Observations, ISM: Supernova Remnants, Astrophysics, Radiation, Power law, Supernova Remnants [ISM], Superposition principle, Raigs gamma, Coincident, MAGIC (telescope), Astrophysics::Galaxy Astrophysics, supernova remnants, Physics, Molecular cloud, Gamma rays, Astrophysics (astro-ph), observations [gamma rays], Astronomy and Astrophysics, Galactic plane, Space and Planetary Science, Electrónica, Física nuclear, Electricidad
Abstract: Recently, the HESS array has reported the detection of gamma-ray emission above a few hundred GeV from eight new sources located close to the Galactic Plane. The source HESS J1834-087 is spatially coincident with SNR G23.3-0.3 (W41). Here we present MAGIC observations of this source, resulting in the detection of a differential gamma-ray flux consistent with a power law, described as dN/(dA dt dE) = (3.7 +/- 0.6)*10^(-12) (E/TeV)^(-2.5 +/- 0.2) \ cm^(-2)s^(-1)TeV^(-1). We confirm the extended character of this flux. We briefly discuss the observational technique used, the procedure implemented for the data analysis, and put this detection in the perspective of the molecular environment found in the region of W41. We present 13CO and 12CO emission maps showing the existence of a massive molecular cloud in spatial superposition with the MAGIC detection., Comment: Accepted by ApJ Letters
Published: 2006
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30. Evaluation of dynamic recurrence risk for locally advanced gastric cancer in the clinical setting of adjuvant chemotherapy: a real-world study with IPTW-based conditional recurrence analysis.

Author: Wu D, Lu J, Xue Z, Zhong Q, Xu BB, Zheng HL, Lin GS, Shen LL, Lin J, Huang JB, Hakobyan D, Li P, Wang JB, Lin JX, Chen QY, Cao LL, Xie JW, Huang CM, and Zheng CH
Subjects: Humans, Chemotherapy, Adjuvant, Gastrectomy, Neoadjuvant Therapy, Probability, Retrospective Studies, Stomach Neoplasms drug therapy, Stomach Neoplasms surgery, Stomach Neoplasms pathology
Abstract: Background: The long-term dynamic recurrence hazard of locally advanced gastric cancer (LAGC) in the clinical setting of adjuvant chemotherapy (ACT) remains unclear., Purpose: This study aimed to investigate the dynamic recurrence risk of LAGC in patients who received ACT or not., Methods: The study assessed data from patients with LAGC who underwent radical gastrectomy between January, 2010 and October, 2015. Inverse probability of treatment weighting (IPTW) was performed to reduce selection bias between the ACT and observational (OBS) groups. Conditional recurrence-free survival (cRFS) and restricted mean survival time (RMST) were used to assess the survival differences., Results: In total, 1,661 LAGC patients were included (ACT group, n = 1,236 and OBS group, n = 425). The recurrence hazard gradually declined; in contrast, cRFS increased with RFS already accrued. Following IPTW adjustment, the cRFS rates were higher in the ACT group than those in the OBS group for patients at baseline or with accrued RFS of 1 and 2 years (p˂0.05). However, the cRFS rates of the ACT group were comparable with those of the OBS group for patients with accrued RFS of 3 or more years (p > 0.05). Likewise, the 5-year △RMST between the ACT and OBS groups demonstrated a similar trend. Moreover, the hematological metastasis rate of the ACT group was significantly lower than that of the OBS group for patients at baseline or with accrued RFS of 1 and 2 years, respectively (p˂0.05)., Conclusions: Although ACT could provide substantial benefits for patients with LAGC, the differences in recurrence hazard between the ACT and OBS groups may attenuate over time, which could help guide surveillance and alleviate patients' anxiety. Further prospective large-scale studies are warranted., (© 2023. BioMed Central Ltd., part of Springer Nature.)
Published: 2023
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31. Laser-assisted 3D bioprinting of exocrine pancreas spheroid models for cancer initiation study.

Author: Hakobyan D, Médina C, Dusserre N, Stachowicz ML, Handschin C, Fricain JC, Guillermet-Guibert J, and Oliveira H
Subjects: Acinar Cells metabolism, Acinar Cells pathology, Animals, Carcinogenesis metabolism, Cell Line, Cell Transdifferentiation, ErbB Receptors metabolism, Gelatin chemistry, Imaging, Three-Dimensional, Ki-67 Antigen metabolism, Methacrylates chemistry, Pancreatic Neoplasms metabolism, Rats, Spheroids, Cellular metabolism, Swine, Bioprinting, Carcinogenesis pathology, Lasers, Pancreas, Exocrine pathology, Pancreatic Neoplasms pathology, Printing, Three-Dimensional, Spheroids, Cellular pathology
Abstract: Pancreatic ductal adenocarcinoma (PDAC) is the most common malignancy of the pancreas. It has shown a poor prognosis and a rising incidence in the developed world. Other pathologies associated with this tissue include pancreatitis, a risk condition for pancreatic cancer. The onset of both pancreatitis and pancreatic cancer follows a common pattern: exocrine pancreatic acinar cells undergo a transdifferentiation to duct cells that triggers a 3D restructuration of the pancreatic tissue. However, the exact mechanism underlying this process remains partially undefined. Further understanding the cellular events leading to PDAC could open new avenues in the development of novel therapeutic approaches. Since current 2D cell culture models fail to mimic the tridimensional complexity of the pancreatic tissue, new in vitro models are urgently needed. Here, we generated 3D pancreatic cell spheroid arrays using laser-assisted bioprinting and characterized their phenotypic evolution over time through image analysis and phenotypic characterization. We show that these bioprinted spheroids, composed of both acinar and ductal cells, can replicate the initial stages of PDAC development. This bioprinted miniaturized spheroid-based array model should prove useful for the study of the internal and external factors that contribute to the formation of precursor PDAC lesions and to cancer progression, and may therefore shed light on future PDAC therapy strategies.
Published: 2020
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32. Laser-Assisted Bioprinting for Bone Repair.

Author: Hakobyan D, Kerouredan O, Remy M, Dusserre N, Medina C, Devillard R, Fricain JC, and Oliveira H
Subjects: Animals, Biocompatible Materials, Bone Regeneration, Collagen Type I, Durapatite, Equipment Design, Lasers, Solid-State, Mesenchymal Stem Cell Transplantation, Mesenchymal Stem Cells, Mice, Nanostructures, Skull injuries, Skull surgery, Bioprinting methods, Bone Substitutes
Abstract: Bioprinting is a novel technological approach that has the potential to solve unmet questions in the field of tissue engineering. Laser-assisted bioprinting (LAB), due to its unprecedented cell printing resolution and precision, is an attractive tool for the in situ printing of a bone substitute. Here, we describe the protocol for LAB and its use for the in situ bioprinting of mesenchymal stromal cells, associated with collagen and nanohydroxyapatite, in order to favor bone regeneration in a calvaria defect model in mice.
Published: 2020
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33. Comparing an All-Atom and a Coarse-Grained Description of Lipid Bilayers in Terms of Enthalpies and Entropies: From MD Simulations to 2D Lattice Models.

Author: Hakobyan D and Heuer A
Subjects: 1,2-Dipalmitoylphosphatidylcholine chemistry, Gels chemistry, Monte Carlo Method, Phase Transition, Temperature, Thermodynamics, Lipid Bilayers chemistry, Molecular Dynamics Simulation
Abstract: Simulations of lipid bilayers at different levels of detail is of major interest in computational biophysics. With a recently proposed algorithm, by mapping the information from a Molecular Dynamics (MD) simulation of a lipid bilayer on a 2D lattice model, it is possible to gain insight into the enthalpic and entropic contributions, governing the interaction of adjacent lipids and the individual chain entropy, respectively. The contributions are obtained as a function of the lipid chain order parameter. Here we use this approach for the case of pure DPPC (1,2-dipalmitoyl- sn -glycero-3-phosphocholine) to compare the all-atom CHARMM36 DPPC lipid with the respective MARTINI coarse-grained DPPC lipid. We individually compare the enthalpy and entropy functions as well as the resulting free energies. This allows us to gain new insight into the comparison of both levels of description. When numerically solving the 2D lattice model via Monte Carlo (MC) simulations, the 2D model displays the gel/liquid transition at the same temperature as the respective MD simulation. The dramatic increase in efficiency of the 2D lattice model as compared to the MD simulation allows us to estimate the equilibrium order parameters of the gel phase, inaccessible by the MD simulations even after 3 μs.
Published: 2019
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34. In situ prevascularization designed by laser-assisted bioprinting: effect on bone regeneration.

Author: Kérourédan O, Hakobyan D, Rémy M, Ziane S, Dusserre N, Fricain JC, Delmond S, Thébaud NB, and Devillard R
Subjects: Animals, Cell Count, Female, Fluorescence, Human Umbilical Vein Endothelial Cells metabolism, Humans, Mice, Skull pathology, X-Ray Microtomography, Bioprinting, Bone Regeneration physiology, Lasers, Neovascularization, Physiologic
Abstract: Vascularization plays a crucial role in bone formation and regeneration process. Development of a functional vasculature to improve survival and integration of tissue-engineered bone substitutes remains a major challenge. Biofabrication technologies, such as bioprinting, have been introduced as promising alternatives to overcome issues related to lack of prevascularization and poor organization of vascular networks within the bone substitutes. In this context, this study aimed at organizing endothelial cells in situ, in a mouse calvaria bone defect, to generate a prevascularization with a defined architecture, and promote in vivo bone regeneration. Laser-assisted bioprinting (LAB) was used to pattern Red Fluorescent Protein-labeled endothelial cells into a mouse calvaria bone defect of critical size, filled with collagen containing mesenchymal stem cells and vascular endothelial growth factor. LAB technology allowed safe and controlled in vivo printing of different cell patterns. In situ printing of endothelial cells gave rise to organized microvascular networks into bone defects. At two months, vascularization rate (vr) and bone regeneration rate (br) showed statistically significant differences between the 'random seeding' condition and both 'disc' pattern (vr = +203.6%; br = +294.1%) and 'crossed circle' pattern (vr = +355%; br = +602.1%). These results indicate that in vivo LAB is a valuable tool to introduce in situ prevascularization with a defined configuration and promote bone regeneration.
Published: 2019
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35. Understanding Conformational Dynamics of Complex Lipid Mixtures Relevant to Biology.

Author: Friedman R, Khalid S, Aponte-Santamaría C, Arutyunova E, Becker M, Boyd KJ, Christensen M, Coimbra JTS, Concilio S, Daday C, van Eerden FJ, Fernandes PA, Gräter F, Hakobyan D, Heuer A, Karathanou K, Keller F, Lemieux MJ, Marrink SJ, May ER, Mazumdar A, Naftalin R, Pickholz M, Piotto S, Pohl P, Quinn P, Ramos MJ, Schiøtt B, Sengupta D, Sessa L, Vanni S, Zeppelin T, Zoni V, Bondar AN, and Domene C
Subjects: Molecular Dynamics Simulation, Protein Binding, Thermodynamics, Cell Membrane chemistry, Cell Membrane metabolism, Computational Biology methods, Lipid Bilayers chemistry
Abstract: This is a perspective article entitled "Frontiers in computational biophysics: understanding conformational dynamics of complex lipid mixtures relevant to biology" which is following a CECAM meeting with the same name.
Published: 2018
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36. [Laser-assisted bioprinting: a novel approach for bone regeneration applications].

Author: Oliveira H, Dusserre N, Hakobyan D, and Fricain JC
Subjects: Animals, Bioprinting instrumentation, Humans, Mice, Prostheses and Implants, Prosthesis Design instrumentation, Prosthesis Design methods, Tissue Engineering instrumentation, Tissue Scaffolds chemistry, Bioprinting methods, Bone Regeneration physiology, Lasers, Printing, Three-Dimensional, Tissue Engineering methods
Published: 2018
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37. Modeling of annexin A2-Membrane interactions by molecular dynamics simulations.

Author: Hakobyan D, Gerke V, and Heuer A
Subjects: Calcium metabolism, Cations, Divalent metabolism, Cytosol metabolism, Dimerization, Phosphatidylserines chemistry, Protein Binding, Surface Properties, Annexin A2 metabolism, Membranes, Artificial, Molecular Dynamics Simulation
Abstract: The annexins are a family of Ca2+-regulated phospholipid binding proteins that are involved in membrane domain organization and membrane trafficking. Although they are widely studied and crystal structures are available for several soluble annexins their mode of membrane association has never been studied at the molecular level. Here we obtained molecular information on the annexin-membrane interaction that could serve as paradigm for the peripheral membrane association of cytosolic proteins by Molecular Dynamics simulations. We analyzed systems containing the monomeric annexin A2 (AnxA2), a membrane with negatively charged phosphatidylserine (POPS) lipids as well as Ca2+ ions. On the atomic level we identify the AnxA2 orientations and the respective residues which display the strongest interaction with Ca2+ ions and the membrane. The simulation results fully agree with earlier experimental findings concerning the positioning of bound Ca2+ ions. Furthermore, we identify for the first time a significant interaction between lysine residues of the protein and POPS lipids that occurs independently of Ca2+ suggesting that AnxA2-membrane interactions can also occur in a low Ca2+ environment. Finally, by varying Ca2+ concentrations and lipid composition in our simulations we observe a calcium-induced negative curvature of the membrane as well as an AnxA2-induced lipid ordering.
Published: 2017
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38. 2D lattice model of a lipid bilayer: Microscopic derivation and thermodynamic exploration.

Author: Hakobyan D and Heuer A
Subjects: 1,2-Dipalmitoylphosphatidylcholine chemistry, Molecular Dynamics Simulation, Monte Carlo Method, Phase Transition, Temperature, 1,2-Dipalmitoylphosphatidylcholine analogs & derivatives, Lipid Bilayers chemistry, Thermodynamics
Abstract: Based on all-atom Molecular Dynamics (MD) simulations of a lipid bilayer we present a systematic mapping on a 2D lattice model. Keeping the lipid type and the chain order parameter as key variables we derive a free energy functional, containing the enthalpic interaction of adjacent lipids as well as the tail entropy. The functional form of both functions is explicitly determined for saturated and polyunsaturated lipids. By studying the lattice model via Monte Carlo simulations it is possible to reproduce the temperature dependence of the distribution of order parameters of the pure lipids, including the prediction of the gel transition. Furthermore, application to a mixture of saturated and polyunsaturated lipids yields the correct phase separation behavior at lower temperatures with a simulation time reduced by approximately 7 orders of magnitude as compared to the corresponding MD simulations. Even the time-dependence of the de-mixing is reproduced on a semi-quantitative level. Due to the generality of the approach we envisage a large number of further applications, ranging from modeling larger sets of lipids, sterols, and solvent proteins to predicting nucleation barriers for the melting of lipids. Particularly, from the properties of the 2D lattice model one can directly read off the enthalpy and entropy change of the 1,2-dipalmitoyl-sn-glycero-3-phosphocholine gel-to-liquid transition in excellent agreement with experimental and MD results.
Published: 2017
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39. Hybrid curved nano-structured micro-optical elements.

Author: Balčytis A, Hakobyan D, Gabalis M, Žukauskas A, Urbonas D, Malinauskas M, Petruškevičius R, Brasselet E, and Juodkazis S
Abstract: Tailoring the spatial degree of freedom of light is an essential step towards the realization of advanced optical manipulation tools. A topical challenge consists of device miniaturization for improved performance and enhanced functionality at the micron scale. We demonstrate a novel approach that combines the additive three-dimensional (3D) structuring capability of laser polymerization and the subtractive subwavelength resolution patterning of focused ion beam lithography. As a case in point hybrid (dielectric/metallic) micro-optical elements that deliver a well-defined topological shaping of light are produced. Here we report on hybrid 3D binary spiral zone plates with unit and double topological charge. Their optical performances are compared to corresponding 2D counterparts both numerically and experimentally. Cooperative refractive capabilities without compromising topological beam shaping are shown. Realization of advanced designs where the dielectric architecture itself is endowed with singular properties is also discussed.
Published: 2016
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40. Optical torque reversal and spin-orbit rotational Doppler shift experiments.

Author: Hakobyan D and Brasselet E
Abstract: We report on optical rotational Doppler frequency shift experiments in the context of a counter-intuitive optomechanical phenomenon that is the angular analog of so-called negative optical radiation forces, which involves spin-orbit scattering of light. In practice, spin-orbit opto-mechanical effects arising from the interaction between polarized light and azimuthally varying birefringent optical elements are retrieved from mechano-optical experiments that involve spatial of the medium. Two kinds of experiments (single-beam and two-beam geometries) are performed and both approaches are discussed in the framework of previous dynamical geometric phase and rotational Doppler shift experiments based on spin and/or orbital angular momentum of light.
Published: 2015
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41. Key molecular requirements for raft formation in lipid/cholesterol membranes.

Author: Hakobyan D and Heuer A
Subjects: 1,2-Dipalmitoylphosphatidylcholine chemistry, Entropy, Lipid Bilayers chemistry, Membrane Lipids chemistry, Models, Chemical, Molecular Conformation, Molecular Dynamics Simulation, 1,2-Dipalmitoylphosphatidylcholine analogs & derivatives, Cholesterol chemistry, Membrane Microdomains chemistry, Phosphatidylcholines chemistry
Abstract: The lipid mixture of DPPC (saturated lipid)/DUPC (unsaturated lipid)/CHOL (cholesterol) is studied with respect to its ability to form liquid-ordered and liquid-disordered phases. We employ coarse-grained simulations with MARTINI force field. All three components are systematically modified in order to explore the relevant molecular properties, leading to phase separation. Specifically, we show that the DPPC/DUPC/CHOL system unmixes due to enthalpic DPPC-DPPC and DPPC-CHOL interactions. The phase separation remains unchanged, except for the formation of a gel phase at long times after decreasing the conformational degrees of freedom of the unsaturated DUPC. In contrast, the phase separation can be suppressed by softening the DPPC chains. In an attempt to mimic the ordering and unmixing effect of CHOL the latter is replaced by a stiff and shortened DPPC-like lipid. One still observes phase separation, suggesting that it is mainly the rigid and planar structure of CHOL which is important for raft formation. Addition of an extra bead to the head of CHOL has no notable impact on the phase separation of the system, supporting the irrelevance of the Umbrella model for the phase separation. Reduction of the conformational entropy of CHOL by stiffening its last bead results in a significant increase of the order of the DPPC/CHOL domain. This suggests that the conformational entropy of CHOL is important to prohibit the gelation process. The interleaflet interactions as mediated by the terminal molecular groups seem to have a strong impact on the possibility of a subsequent gelation process after phase separation.
Published: 2014
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42. Phase separation in a lipid/cholesterol system: comparison of coarse-grained and united-atom simulations.

Author: Hakobyan D and Heuer A
Subjects: 1,2-Dipalmitoylphosphatidylcholine chemistry, Computer Simulation, Diffusion, Kinetics, Temperature, Thermodynamics, 1,2-Dipalmitoylphosphatidylcholine analogs & derivatives, Cholesterol chemistry, Lipid Bilayers chemistry, Models, Molecular, Phosphatidylcholines chemistry
Abstract: Ternary mixtures of saturated and unsaturated phospholipids and cholesterol constitute a well-known model system to study raft formation in membranes. This phenomenon is, e.g., observed in cell membranes. Here, coarse-grained (CG) and microscopic united-atom (UA) simulations are performed to investigate the phase separation of a membrane bilayer for the ternary system of saturated 16:0 (DPPC) and unsaturated 18:2 (DUPC) phospholipids and cholesterol (CHOL). The results of a 9 μs UA simulation demonstrate the onset of phase separation and can be compared with properties of the corresponding CG system. While sharing the structural features of phase separation in the CG model, the onset of demixing for the UA model is 40 times slower. This factor can be rationalized by the different short-time diffusion constants. Various system properties such as order parameters and lipid-CHOL and CHOL-CHOL interactions are analyzed and compared between the UA and CG models. From the structural perspective, the phase separation process appears to be rather similar for both models, which illustrates once more the power of using CG approaches.
Published: 2013
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43. Molecular dynamics study of interaction and substrate channeling between neuron-specific enolase and B-type phosphoglycerate mutase.

Author: Hakobyan D and Nazaryan K
Subjects: Humans, Isoenzymes, Protein Binding, Protein Interaction Mapping, Thermodynamics, Molecular Dynamics Simulation, Phosphoglycerate Mutase chemistry, Phosphoglycerate Mutase metabolism, Phosphopyruvate Hydratase chemistry, Phosphopyruvate Hydratase metabolism
Abstract: Phosphoglycerate mutase (PGM) and enolase are consecutive enzymes in the glycolytic pathway. We used molecular dynamics simulation to examine the interaction of human B-type PGM (dPGM-B) and neuron-specific enolase (NSE). Specifically, we studied the interactions of 31 orientations of these enzymes by means of the effective energy function implicit solvation method. Interactions between active regions of the enzymes occurred preferentially, although the strongest interactions appeared to be between the back side of NSE and the active regions of dPGM-B. Cleavage of 2PG from dPGM-B was investigated, and the Ser(14)-Leu(30) loop of dPGM-B is suggested as a cleavage site and, likely, another entrance site of a ligand. Substrate channeling between the enzymes was observed when NSE with its active regions Leu(11)-Asn(16), Arg(49)-Lys(59), and Gly(155)-Ala(158) covered the Ser(14)-Leu(30) loop of dPGM-B. Analyses of the results make us believe that the channeling between PGM and enolase "benefits" from weak interaction. The probability of formation of channeling favorable complex is estimated to be up to 5%, while functional interaction between NSE and dPGM-B might be as high as 20%. NSE and dPGM-B functional interaction seems not to be isotype specific., (Proteins 2010. (c) 2010 Wiley-Liss, Inc.)
Published: 2010
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44. Variable very-high-energy gamma-ray emission from the microquasar LS I +61 303.

Author: Albert J, Aliu E, Anderhub H, Antoranz P, Armada A, Asensio M, Baixeras C, Barrio JA, Bartelt M, Bartko H, Bastieri D, Bavikadi SR, Bednarek W, Berger K, Bigongiari C, Biland A, Bisesi E, Bock RK, Bordas P, Bosch-Ramon V, Bretz T, Britvitch I, Camara M, Carmona E, Chilingarian A, Ciprini S, Coarasa JA, Commichau S, Contreras JL, Cortina J, Curtef V, Danielyan V, Dazzi F, De Angelis A, de Los Reyes R, De Lotto B, Domingo-Santamaría E, Dorner D, Doro M, Errando M, Fagiolini M, Ferenc D, Fernández E, Firpo R, Flix J, Fonseca MV, Font L, Fuchs M, Galante N, Garczarczyk M, Gaug M, Giller M, Goebel F, Hakobyan D, Hayashida M, Hengstebeck T, Höhne D, Hose J, Hsu CC, Isar PG, Jacon P, Kalekin O, Kosyra R, Kranich D, Laatiaoui M, Laille A, Lenisa T, Liebing P, Lindfors E, Lombardi S, Longo F, López J, López M, Lorenz E, Lucarelli F, Majumdar P, Maneva G, Mannheim K, Mansutti O, Mariotti M, Martínez M, Mase K, Mazin D, Merck C, Meucci M, Meyer M, Miranda JM, Mirzoyan R, Mizobuchi S, Moralejo A, Nilsson K, Oña-Wilhelmi E, Orduña R, Otte N, Oya I, Paneque D, Paoletti R, Paredes JM, Pasanen M, Pascoli D, Pauss F, Pavel N, Pegna R, Persic M, Peruzzo L, Piccioli A, Poller M, Pooley G, Prandini E, Raymers A, Rhode W, Ribó M, Rico J, Riegel B, Rissi M, Robert A, Romero GE, Rügamer S, Saggion A, Sánchez A, Sartori P, Scalzotto V, Scapin V, Schmitt R, Schweizer T, Shayduk M, Shinozaki K, Shore SN, Sidro N, Sillanpää A, Sobczynska D, Stamerra A, Stark LS, Takalo L, Temnikov P, Tescaro D, Teshima M, Tonello N, Torres A, Torres DF, Turini N, Vankov H, Vitale V, Wagner RM, Wibig T, Wittek W, Zanin R, and Zapatero J
Abstract: Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.
Published: 2006
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45. Investigation of interaction between enolase and phosphoglycerate mutase using molecular dynamics simulation.

Author: Hakobyan D and Nazaryan K
Subjects: Binding Sites, Catalytic Domain, Humans, Molecular Conformation, Phosphoglycerate Mutase chemistry, Phosphopyruvate Hydratase chemistry, Protein Conformation, Computer Simulation, Models, Molecular, Phosphoglycerate Mutase metabolism, Phosphopyruvate Hydratase metabolism
Abstract: Two glycolytic enzymes, phosphoglycerate mutase (PGM) and enolase from Saccharomyces cerevisiae have been chosen to detect complex formation between active centers (a/c), using molecular dynamics simulation. Enzymes have been separated by 10 A distance and placed in a water box of size 173 x 173 x 173 A. Three different orientations where a/c of PGM and enolase were positioned toward each other have been used for investigation. The two initial 3-phosphoglycerate substrates at near active centers of initial structure of PGM have been replaced with final 2-phosphoglycerate products. 150mM of NaCl have been added to the system to observe binding activity in the near physiological conditions. Analysis of interaction energies and conformation changes for 3ns simulation indicates that PGM and enolase do show binding affinity between their near active regions. Moreover the similarity between final conformations of the first two orientations with the initial conformation of the third orientation suggests that complex formation between a/c of enzymes is not confined only by discussed orientations. Clear interaction of enolase with C-terminal tail of PGM has been recorded. These results suggest that substrate direct transfer mechanism may exist between enzymes.
Published: 2006
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46. Molecular dynamics simulation of interactions in glycolytic enzymes.

Author: Hakobyan D and Nazaryan K
Subjects: Binding Sites, Computer Simulation, Glyceric Acids chemistry, Glyceric Acids metabolism, Hydrogen Bonding, Hydrophobic and Hydrophilic Interactions, Kinetics, Models, Molecular, Molecular Conformation, Osmolar Concentration, Phosphoglycerate Mutase metabolism, Phosphopyruvate Hydratase metabolism, Protein Binding, Protein Conformation, Sodium Chloride chemistry, Sodium Chloride metabolism, Substrate Specificity, Water chemistry, Water metabolism, Glycolysis, Phosphoglycerate Mutase chemistry, Phosphopyruvate Hydratase chemistry
Abstract: Two glycolytic enzymes, phosphoglycerate mutase (PGM) and enolase from Saccharomyces cerevisiae, have been chosen to detect complex formation and possible channeling, using molecular dynamics simulation. The enzymes were separated by 10 angstroms distance and placed in a water-filled box of size 173 x 173 x 173 angstroms. Three different orientations have been investigated. The two initial 3-phosphoglycerate substrate molecules near the active centers of the initial structure of PGM have been replaced with final product (2-phosphoglycerate) molecules, and 150 mM NaCl together with three Mg2+ ions have been added to the system to observe post-catalytic activity under near-physiological conditions. Analysis of interaction energies and conformation changes for 3 nsec simulation indicates that PGM and enolase do show binding affinity between their near active regions, which is necessary for channeling to occur. Interaction of the C-terminal residues Ala239 and Val240 of PGM (which partially "cap" the 2-phosphoglycerate) with enolase also favors the existence of channeling.
Published: 2006
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