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1. Observation of a relatively low luminosity long duration GRB 201015A by the MAGIC telescopes

Author

Suda, Yusuke, Artero, Manuel, Asano, Katsuaki, Berti, Alessio, Nava, Lara, Noda, Koji, Terauchi, Kenta, Acciari, V.A., Ansoldi, S., Antonelli, L.A., Arbet Engels, A., Baack, D., Babić, A., Baquero, A., Barres de Almeida, Ulisses, Barrio, J.A., Batković, I., Becerra González, J., Bednarek, W., Bellizzi, L., and Biland, A.

Subjects
Tellurium compounds, Supernovae, Cosmic rays, Cosmology, Telescopes
Abstract

Starting from the first announcement of unequivocal detection of very high energy (VHE) emission from a gamma-ray burst (GRB) by the MAGIC telescopes (GRB 190114C), four additional detections of VHE emission from GRBs by ground-based telescopes were reported. These observations have revealed a new, energetic component that has become an additional probe to explore GRB physics. In order to deepen our understanding of the origin of this new component, and in general of the origin of radiation from GRBs, further observations by VHE instruments are crucial. In this work we report fast follow-up observations by the MAGIC telescopes of GRB 201015A, a GRB detected by the Swift/BAT. As measured by BAT, the prompt emission lasted 9.8 ± 3.5 seconds, suggesting that this GRB belongs to the class of long events. This was later confirmed by optical observations, which allowed to measure the redshift (z = 0.42) and found the associated type Ic-BL supernova. Having a prompt isotropic-equivalent energy of Eiso ∼1050 erg, this GRB is a relatively low energy event as compared to the population of long GRBs. Observations with the MAGIC telescopes started about 30 seconds after the GRB onset and were performed under good observational conditions. The accurate analysis of the MAGIC data reveals a strong hint of detection and implies a significant energy release in the TeV range, smaller but comparable with that of the prompt emission in the keV-MeV band., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

Published
2022

2. Combined searches for dark matter in dwarf spheroidal galaxies observed with the MAGIC telescopes, including new data from Coma Berenices and Draco

Author

MAGIC Collaboration, Acciari, V., Ansoldi, S., Antonelli, L., Arbet Engels, A., Artero, M., Asano, K., Baack, D., Babić, A., Baquero, A., Barres de Almeida, U., Barrio, J., Batković, I., Becerra González, J., Bednarek, W., Bellizzi, L., Bernardini, E., Bernardos, M., Berti, A., Besenrieder, J., Bhattacharyya, W., Bigongiari, C., Biland, A., Blanch, O., Bökenkamp, H., Bonnoli, G., Bošnjak, Ž., Busetto, G., Carosi, R., Ceribella, G., Cerruti, M., Chai, Y., Chilingarian, A., Cikota, S., Colak, S., Colombo, E., Contreras, J., Cortina, J., Covino, S., D'Amico, G., D'Elia, V., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., Delfino, M., Delgado, J., Delgado Mendez, C., Depaoli, D., Di Pierro, F., Di Venere, L., Do Souto Espiñeira, E., Dominis Prester, D., Donini, A., Dorner, D., Doro, M., Elsaesser, D., Fallah Ramazani, V., Fattorini, A., Fonseca, M., Font, L., Fruck, C., Fukami, S., García López, R., Garczarczyk, M., Gasparyan, S., Gaug, M., Giglietto, N., Giordano, F., Gliwny, P., Godinović, N., Green, J., Green, D., Hadasch, D., Hahn, A., Heckmann, L., Herrera, J., Hoang, J., Hrupec, D., Hütten, M., Inada, T., Ishio, K., Iwamura, Y., Jiménez, I., Jormanainen, J., Jouvin, L., Karjalainen, M., Kerszberg, D., Kobayashi, Y., Kubo, H., Kushida, J., Lamastra, A., Lelas, D., Leone, F., Lindfors, E., Linhoff, L., Lombardi, S., Longo, F., López-Coto, R., López-Moya, M., López-Oramas, A., Loporchio, S., Machado de Oliveira Fraga, B., Maggio, C., Majumdar, P., Makariev, M., Mallamaci, M., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Mariotti, M., Martínez, M., Mazin, D., Menchiari, S., Mender, S., Mićanović, S., Miceli, D., Miener, T., Miranda, J., Mirzoyan, R., Molina, E., Moralejo, A., Morcuende, D., Moreno, V., Moretti, E., Neustroev, V., Nigro, C., Nilsson, K., Ninci, D., Nishijima, K., Noda, K., Nozaki, S., Ohtani, Y., Oka, T., Otero-Santos, J., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J., Pavletić, L., Peñil, P., Persic, M., Pihet, M., Prada Moroni, P., Prandini, E., Priyadarshi, C., Puljak, I., Rhode, W., Ribó, M., Rico, J., Righi, C., Rugliancich, A., Saha, L., Sahakyan, N., Saito, T., Sakurai, S., Satalecka, K., Saturni, F., Schleicher, B., Schmidt, K., Schweizer, T., Sitarek, J., Šnidarić, I., Sobczynska, D., Spolon, A., Stamerra, A., Strišković, J., Strom, D., Strzys, M., Suda, Y., Surić, T., Takahashi, M., Takeishi, R., Tavecchio, F., Temnikov, P., Terzić, T., Teshima, M., Tosti, L., Truzzi, S., Tutone, A., Ubach, S., van Scherpenberg, J., Vanzo, G., Vazquez Acosta, M., Ventura, S., Verguilov, V., Vigorito, C., Vitale, V., Vovk, I., Will, M., Wunderlich, C., Zarić, D., Département de Physique des Particules (ex SPP) (DPhP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), MAGIC, Département de Physique des Particules (ex SPP) (DPP), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Academy of Finland, German Research Foundation, European Commission, Ministerio de Economía y Competitividad (España), and Japan Society for the Promotion of Science

Subjects
Astrophysics and Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Dark Matter, Indirect searches, Gamma Rays, Dwarf spheroidal galaxies, Imaging Atmospheric Cherenkov, Telescopes, 01 natural sciences, WIMP: annihilation, Imaging Atmospheric Cherenkov Telescopes, 0103 physical sciences, TeV, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, 010308 nuclear & particles physics, imaging, Dark Matter Indirect searches Gamma Rays Dwarf spheroidal galaxies Imaging Atmospheric Cherenkov Telescopes, Astronomy and Astrophysics, dark matter: annihilation, sensitivity, MAGIC, gamma ray: emission, Cherenkov counter, Space and Planetary Science, quality, Física nuclear, galaxy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

T.M. Collaboration, V.A. Acciari, S. Ansoldi et al., Milky Way dwarf spheroidal galaxies (dSphs) are among the best candidates to search for signals of dark matter annihilation with Imaging Atmospheric Cherenkov Telescopes, given their high mass-to-light ratios and the fact that they are free of astrophysical gamma-ray emitting sources. Since 2011, MAGIC has performed a multi-year observation program in search for Weakly Interacting Massive Particles (WIMPs) in dSphs. Results on the observations of Segue 1 and Ursa Major II dSphs have already been published and include some of the most stringent upper limits (ULs) on the velocity- averaged cross-section ⟨σannv⟩ of WIMP annihilation from observations of dSphs. In this work, we report on the analyses of 52.1 h of data of Draco dSph and 49.5 h of Coma Berenices dSph observed with the MAGIC telescopes in 2018 and in 2019 respectively. No hint of a signal has been detected from either of these targets and new constraints on the ⟨σannv⟩ of WIMP candidates have been derived. In order to improve the sensitivity of the search and reduce the effect of the systematic uncertainties due to the J-factor estimates, we have combined the data of all dSphs observed with the MAGIC telescopes. Using 354.3 h of dSphs good quality data, 95% CL ULs on ⟨σannv⟩ have been obtained for 9 annihilation channels. For most of the channels, these results reach values of the order of 10−24 cm3/s at ∼1 TeV and are the most stringent limits obtained with the MAGIC telescopes so far., he financial support of the German BMBF, MPG and HGF; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish Ministerio de Ciencia e Innovación (MICINN) (PID2019-104114RB-C31, PID2019-104114RB-C32, PID2019-104114RB-C33, PID2019-105510GB-C31, PID2019-107847RB-C41, PID2019-107847RB-C42, PID2019-107988GB-C22); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-400/18.12.2020 and the Academy of Finland grant nr. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia ‘‘Severo Ochoa’’ (SEV-2016-0588, CEX2019-000920-S), the Unidad de Excelencia ‘‘María de Maeztu’’ (CEX2019-000918-M, MDM-2015-0509-18-2) and by the CERCA program of the Generalitat de Catalunya; by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02; by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3; the Polish National Research Centre grant UMO- 2016/22/M/ST9/00382; and by the Brazilian MCTIC, CNPq and FAPERJ. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 754510.

Published
2022

3. Optical spectroscopy of blazars for the Cherenkov Telescope Array – II.

Author

Kasai, E, Goldoni, P, Pita, S, Williams, D A, Max-Moerbeck, W, Hervet, O, Cotter, G, Backes, M, Boisson, C, Becerra González, J, Barres de Almeida, U, D'Ammando, F, Fallah Ramazani, V, and Lindfors, E

Subjects
BL Lacertae objects, ACTIVE galactic nuclei, TELESCOPES, RADIO galaxies, GAMMA rays, TECHNOLOGICAL innovations, OPTICAL spectroscopy
Abstract

Active galactic nuclei (AGNs) make up about 35 per cent of the more than 250 sources detected in very high-energy (VHE) gamma rays to date with the imaging atmospheric Cherenkov telescopes. Apart from four nearby radio galaxies and two AGNs of unknown type, all known VHE AGNs are blazars. Knowledge of the cosmological redshift of gamma-ray blazars is key to enabling the study of their intrinsic emission properties, as the interaction between gamma rays and the extragalactic background light (EBL) results in a spectral softening. Therefore, the redshift determination exercise is crucial to indirectly placing tight constraints on the EBL density, and to studying blazar population evolution across cosmic time. Due to the powerful relativistic jets in blazars, most of their host galaxies' spectral features are outshined, and dedicated high signal-to-noise (S/N) spectroscopic observations are required. Deep medium- to high-resolution spectroscopy of 33 gamma-ray blazar optical counterparts was performed with the European Southern Observatory, New Technology Telescope, Keck II telescope, Shane 3-metre telescope, and the Southern African Large Telescope. From the sample, spectra from 25 objects display spectral features or are featureless and have high S/N. The other eight objects have low-quality featureless spectra. We systematically searched for absorption and emission features and estimated, when possible, the fractional host galaxy flux in the measured total flux. Our measurements yielded 14 firm spectroscopic redshifts, ranging from 0.0838 to 0.8125, one tentative redshift, and two lower limits: one at |$z > 0.382$| and the other at z > 0.629. [ABSTRACT FROM AUTHOR]

Published
2023
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4. Studying the nature of the unidentified gamma-ray source HESS J1841−055 with the MAGIC telescopes.

Author

Collaboration, MAGIC, Acciari, V A, Ansoldi, S, Antonelli, L A, Arbet Engels, A, Asano, K, Baack, D, Babić, A, Banerjee, B, Baquero, A, Barres de Almeida, U, Barrio, J A, Becerra González, J, Bednarek, W, Bellizzi, L, Bernardini, E, Bernardos, M, Berti, A, Besenrieder, J, and Bhattacharyya, W

Subjects
SPECTRAL energy distribution, TELESCOPES, GAMMA rays, MOLECULAR clouds, HADRONIC atoms
Abstract

We investigate the physical nature and origin of the gamma-ray emission from the extended source HESS J1841−055 observed at TeV and GeV energies. We observed HESS J1841−055 at TeV energies for a total effective time of 43 h with the MAGIC telescopes, in 2012 and 2013. Additionally, we analysed the GeV counterpart making use of about 10 yr of Fermi -LAT data. Using both Fermi -LAT and MAGIC, we study both the spectral and energy-dependent morphology of the source for almost four decades of energy. The origin of the gamma-ray emission from this region is investigated using multiwaveband information on sources present in this region, suggested to be associated with this unidentified gamma-ray source. We find that the extended emission at GeV–TeV energies is best described by more than one source model. We also perform the first energy-dependent analysis of the HESS J1841−055 region at GeV–TeV. We find that the emission at lower energies comes from a diffuse or extended component, while the major contribution of gamma rays above 1 TeV arises from the southern part of the source. Moreover, we find that a significant curvature is present in the combined observed spectrum of MAGIC and Fermi -LAT. The first multiwavelength spectral energy distribution of this unidentified source shows that the emission at GeV–TeV energies can be well explained with both leptonic and hadronic models. For the leptonic scenario, bremsstrahlung is the dominant emission compared to inverse Compton. On the other hand, for the hadronic model, gamma-ray resulting from the decay of neutral pions (π0) can explain the observed spectrum. The presence of dense molecular clouds overlapping with HESS J1841−055 makes both bremsstrahlung and π0-decay processes the dominant emission mechanisms for the source. [ABSTRACT FROM AUTHOR]

Published
2020
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5. Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes

Author

Aleksić, J., Ansoldi, S., Biasuzzi, B., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Persic, M., Prada Moroni, P. G., Prandini, E., Preziuso, S., Puljak, I., Reinthal, R., Biland, A., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Rügamer, S., Saggion, A., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Blanch, O., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Bonnefoy, S., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Bonnoli, G., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Uellenbeck, M., Vogler, P., Wagner, R. M., Zanin, R., Borracci, F., Horns, D., Martín, J., Meyer, M., MAGIC Collaboration, Bretz, T., Carmona, E., Carosi, A., Colin, P., Antonelli, L. A., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., de Oña Wilhelmi, E., Antoranz, P., Delgado Mendez, C., Doert, M., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fonseca, M. V., Font, L., Babic, A., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Godinović, N., González Muñoz, A., Gozzini, S. R., Bangale, P., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Barrio, J. A., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Becerra González, J., López, M., López-Coto, R., López-Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Bednarek, W., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Bernardini, E., Nakajima, D., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Nowak, N., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., and Universitat de Barcelona

Subjects
Astrofísica, Nuclear and High Energy Physics, Very high energy gamma rays, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astrophysics, 01 natural sciences, Imaging atmospheric Cherenkov telescopes, Raigs gamma, Crab Nebula, MAGIC telescopes, Pulsar wind nebulae, Astronomy and Astrophysics, Space and Planetary Science, 0103 physical sciences, ddc:530, MAGIC (telescope), 010303 astronomy & astrophysics, Pulsars, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Nebula, ta115, Telescopis, 010308 nuclear & particles physics, Gamma rays, Gamma ray, Light curve, Púlsars, Wavelength, Spectral energy distribution, Pulsar Wind Nebulae, Imaging Atmospheric Cherenkov Telescopes, very high energy gamma rays, Astrophysics - High Energy Astrophysical Phenomena, Telescopes
Abstract

The MAGIC stereoscopic system collected 69 hours of Crab Nebula data between October 2009 and April 2011. Analysis of this data sample using the latest improvements in the MAGIC stereoscopic software provided an unprecedented precision of spectral and night-by-night light curve determination at gamma rays. We derived a differential spectrum with a single instrument from 50 GeV up to almost 30 TeV with 5 bins per energy decade. At low energies, MAGIC results, combined with Fermi-LAT data, show a flat and broad Inverse Compton peak. The overall fit to the data between 1 GeV and 30 TeV is not well described by a log-parabola function. We find that a modified log-parabola function with an exponent of 2.5 instead of 2 provides a good description of the data ($\chi^2=35/26$). Using systematic uncertainties of red the MAGIC and Fermi-LAT measurements we determine the position of the Inverse Compton peak to be at (53 $\pm$ 3stat + 31syst -13syst) GeV, which is the most precise estimation up to date and is dominated by the systematic effects. There is no hint of the integral flux variability on daily scales at energies above 300 GeV when systematic uncertainties are included in the flux measurement. We consider three state- of-the-art theoretical models to describe the overall spectral energy distribution of the Crab Nebula. The constant B-field model cannot satisfactorily reproduce the VHE spectral measurements presented in this work, having particular difficulty reproducing the broadness of the observed IC peak. Most probably this implies that the assumption of the homogeneity of the magnetic field inside the nebula is incorrect. On the other hand, the time-dependent 1D spectral model provides a good fit of the new VHE results when considering a 80 {\mu}G magnetic field. However, it fails to match the data when including the morphology of the nebula at lower wavelengths., Comment: accepted by JHEAp, 9 pages, 6 figures

Published
2015

6. New GTC spectroscopic data and a statistical study to better constrain the redshift of the BL Lac RGB J2243 + 203.

Author

Rosa González, D, Muriel, H, Mayya, Y D, Aretxaga, I, Becerra González, J, Carramiñana, A, Méndez-Abreu, J, Vega, O, Terlevich, E, Coutiño de León, S, Furniss, A, Longinotti, A L, Terlevich, R J, Pichel, A C, Rovero, A C, and Donzelli, C

Subjects
TELESCOPES, GALACTIC redshift, ASTRONOMICAL observations, SPECTRUM analysis, PROBABILITY theory
Abstract

We present new spectroscopic data of the BL Lac RGB 2243 + 203, and its surroundings, obtained with the OSIRIS Multi Object Spectrograph (MOS) mounted in the Gran Telescopio Canarias (GTC). The spectra of neither the BL Lac nor its host galaxy show any spectral feature, thus hindering direct determination of its redshift. The spectroscopic redshift distribution of objects in the MOS field of view shows four galaxies with redshift between 0.5258 and 0.5288. We make use of a statistical analysis to test the possibility that the targeted BL Lac may be a member of that group. By using the spectroscopic redshifts obtained with our GTC observations, we found that this probability is between 86  and 93 per cent. [ABSTRACT FROM AUTHOR]

Published
2019
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7. Gamma-ray flaring activity of NGC1275 in 2016–2017 measured by MAGIC.

Author

MAGIC Collaboration, Ansoldi, S., Antonelli, L. A., Arcaro, C., Baack, D., Babić, A., Banerjee, B., Bangale, P., Barres de Almeida, U., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Berse, R. Ch., Berti, A., Bhattacharyya, W., Bigongiari, C., Biland, A., Blanch, O., and Bonnoli, G.

Subjects
CHERENKOV radiation, TELESCOPES, GAMMA rays, NEBULAE, METEOR showers
Abstract

We report on the detection of flaring activity from the Fanaroff-Riley I radio galaxy NGC 1275 in very-high-energy (VHE, E > 100 GeV) gamma rays with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes. The observations were performed between 2016 September and 2017 February, as part of a monitoring programme. The brightest outburst, with ∼1.5 times the Crab Nebula flux above 100 GeV (C.U.), was observed during the night between 2016 December 31 and 2017 January 1. The flux is fifty times higher than the mean flux previously measured in two observational campaigns between 2009 October and 2010 February and between 2010 August and 2011 February. Significant variability of the day-by-day light curve was measured. The shortest flux-doubling timescale was found to be of (611 ± 101) min. The spectra calculated for this period are harder and show a significant curvature with respect to the ones obtained in the previous campaigns. The combined spectrum of the MAGIC data during the strongest flare state and simultaneous data from the Fermi-LAT around 2017 January 1 follows a power law with an exponential cutoff at the energy (492 ± 35) GeV. We further present simultaneous optical flux density measurements in the R-band obtained with the Kungliga Vetenskaps Akademien (KVA) telescope and investigate the correlation between the optical and gamma-ray emission. Due to possible internal pair-production, the fast flux variability constrains the Doppler factor to values that are inconsistent with a large viewing angle as observed in the radio band. We investigate different scenarios for the explanation of fast gamma-ray variability, namely emission from magnetospheric gaps, relativistic blobs propagating in the jet (mini-jets), or an external cloud (or star) entering the jet. We find that the only plausible model to account for the luminosities here observed would be the production of gamma rays in a magnetospheric gap around the central black hole, only in the eventuality of an enhancement of the magnetic field threading the hole from its equipartition value with the gas pressure in the accretion flow. The observed gamma-ray flare therefore challenges all the discussed models for fast variability of VHE gamma-ray emission in active galactic nuclei. [ABSTRACT FROM AUTHOR]

Published
2018
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8. Challenging the one zone SSC model in VHE gamma ray emitting BL lacs: The interesting case of PKS 1424+240.

Author

Prandini, E., Becerra-González, J., Lindfors, E., Mankuzhiyil, N., Stamerra, A., Tavecchio, F., MAGIC Collaboration, Cutini, S., Gasparrini, D., Hovatta, T., Lähteenmäki, A., and Lister, M.

Subjects
*SUPERCONDUCTING Super Collider, *GAMMA rays, *IMAGING systems in astronomy, *TELESCOPES, *DOPPLER effect, *SYNCHROTRONS, *ASTRONOMICAL observations
Abstract

The BL Lac object PKS 1424+240 with uncertain redshift has been investigated by the MAGIC imaging atmospheric Cherenkov telescopes at very high energies (VHE; E> 100 GeV) since 2006. The source was observed in various emission states and the integral flux above 150 GeV shows hints of variability. We present a detailed analysis of the multi-frequency emission, from radio to VHE gamma rays. We show that a simple one-zone synchrotron self Compton (SSC) model is inadequate to account for the observed spectral behavior. In particular, the synchrotron peak is much broader than the high-energy peak and the separation between the two peaks is large, which requires high Doppler factor for modeling. We investigate the correlation between lightcurves in several wavebands and propose a two-zone SSC model to fit the experimental data where part of the observed emission is due to a parsec scale jet and the remaining part to a more compact region close to the central engine. [ABSTRACT FROM AUTHOR]

Published
2012
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9. Unprecedented gamma-ray flare from PG1553+113 in spring 2012.

Author

Becerra-González, J., Da Vela, P., Prandini, E., Stamerra, A., Covino, S., Barres, U., Nilsson, K., MAGIC Collaboration, Lähteenmäki, A., Hovatta, T., Mundell, C., Steele, I., and Neronov, A.

Subjects
*GAMMA rays, *PROTON flares, *REDSHIFT, *NUCLEAR energy, *OPTICAL polarization, *TELESCOPES
Abstract

PG1553 is a well-known TeV blazar, which redshift is still uncertain (z>0.4 [1]). The source has been monitored in Very High Energy (VHE, E>100 GeV) gamma-rays by MAGIC telescopes since February 2005, and detected on a regular basis in a quiescent state with modest flux variations, lying in the range from 4% to 11% of the Crab Nebula flux above 150 GeV [2]. In March and April 2012, strong VHE gamma ray activity was detected with the MAGIC telescopes. The flux state reached unprecedented level of the Crab Nebula flux for PG 1553+113 [3]. A multiwavlength campaign during the flaring episodes has been carried out in radio by Metsa¨hovi and OVRO, in optical by KVA telescope, in optical-UV by Swift/UVOT, in X-rays by Swift/XRT, in infrared by REM telescope and in gamma-rays by Fermi/LAT. In addition, optical polarization measurements were carried out by Liverpool telescope. The multiwavelength behavior is particularly interesting, since the source was active in most of the bands. [ABSTRACT FROM AUTHOR]

Published
2012
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10. Morphological and spectral properties of the W51 region measured with the MAGIC telescopes.

Author

Aleksić, J., Alvarez, E. A., Antonelli, L. A., Antoranz, P., Asensio, M., Backes, M., Barres de Almeida, U., Barrio, J. A., Bastieri, D., Becerra González, J., Bednarek, W., Berger, K., Bernardini, E., Biland, A., Blanch, O., Bock, R. K., Boller, A., Bonnoli, G., Borla Tridon, D., and Bretz, T.

Subjects
MOLECULAR clouds, SUPERNOVAE, TELESCOPES, SPECTRUM analysis, ASTRONOMICAL instruments
Abstract

Context. The W51 complex hosts the supernova remnant W51C which is known to interact with the molecular clouds in the star forming region W51B. In addition, a possible pulsar wind nebula CXO J192318.5+140305 was found likely associated with the supernova remnant. Gamma-ray emission from this region was discovered by Fermi/LAT (between 0.2 and 50 GeV) and H.E.S.S. (>1 TeV). The spatial distribution of the events could not be used to pinpoint the location of the emission among the pulsar wind nebula, the supernova remnant shell and/or the molecular cloud. However, the modeling of the spectral energy distribution presented by the Fermi/LAT collaboration suggests a hadronic emission mechanism. The possibility that the gamma-ray emission from such an object is of hadronic origin can contribute to solvingthe long-standing problem of the contribution to galactic cosmic rays by supernova remnants. Aims. Our aim is to determine the morphology of the very-high-energy gamma-ray emission of W51 and measure its spectral properties. Methods. We performed observations of the W51 complex with the MAGIC telescopes for more than 50 h. The energy range accessible with MAGIC extends from 50 GeV to several TeV, allowing for the first spectral measurement at these energies. In addition, the good angular resolution in the medium (few hundred GeV) to high (above 1 TeV) energies allow us to perform morphological studies. We look for underlying structures by means of detailed morphological studies. Multi-wavelength data from this source have been sampled to model the emission with both leptonic and hadronic processes. Results. We detect an extended emission of very-high-energy gamma rays, with a significance of 11 standard deviations. We extend the spectrum from the highest Fermi/LAT energies to ∼5 TeV and find that it follows a single power law with an index of 2.58 ± 0.07stat ± 0.22syst. The main part of the emission coincides with the shocked cloud region, while we find a feature extending towards the pulsar wind nebula. The possible contribution of the pulsar wind nebula, assuming a point-like source, shows no dependence on energy and it is about 20% of the overall emission. The broad band spectral energy distribution can be explained with a hadronic model that implies proton acceleration above 100 TeV. This result, together with the morphology of the source, tentatively suggests that we observe ongoing acceleration of ions in the interaction zone between supernova remnant and cloud. [ABSTRACT FROM AUTHOR]

Published
2012
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11. Performance of the MAGIC telescopes under moonlight.

Author

Ahnen, M.L., Ansoldi, S., Antonelli, L.A., Arcaro, C., Babić, A., Banerjee, B., Bangale, P., Barres de Almeida, U., Barrio, J.A., Becerra González, J., Bednarek, W., Bernardini, E., Berti, A., Bhattacharyya, W., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., and Carosi, R.

Subjects
*TELESCOPES, *MOON light, *DARK matter, *ASTRONOMICAL observations, *PHOTOMULTIPLIERS
Abstract

MAGIC, a system of two imaging atmospheric Cherenkov telescopes, achieves its best performance under dark conditions, i.e. in absence of moonlight or twilight. Since operating the telescopes only during dark time would severely limit the duty cycle, observations are also performed when the Moon is present in the sky. Here we develop a dedicated Moon-adapted analysis to characterize the performance of MAGIC under moonlight. We evaluate energy threshold, angular resolution and sensitivity of MAGIC under different background light levels, based on Crab Nebula observations and tuned Monte Carlo simulations. This study includes observations taken under non-standard hardware configurations, such as reducing the camera photomultiplier tubes gain by a factor  ∼ 1.7 (reduced HV settings) with respect to standard settings (nominal HV) or using UV-pass filters to strongly reduce the amount of moonlight reaching the cameras of the telescopes. The Crab Nebula spectrum is correctly reconstructed in all the studied illumination levels, that reach up to 30 times brighter than under dark conditions. The main effect of moonlight is an increase in the analysis energy threshold and in the systematic uncertainties on the flux normalization. The sensitivity degradation is constrained to be below 10%, within 15–30% and between 60 and 80% for nominal HV, reduced HV and UV-pass filter observations, respectively. No worsening of the angular resolution was found. Thanks to observations during moonlight, the maximal duty cycle of MAGIC can be increased from  ∼ 18%, under dark nights only, to up to  ∼ 40% in total with only moderate performance degradation. [ABSTRACT FROM AUTHOR]

Published
2017
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12. The major upgrade of the MAGIC telescopes, Part II: A performance study using observations of the Crab Nebula.

Author

Aleksić, J., Ansoldi, S., Antonelli, L.A., Antoranz, P., Babic, A., Bangale, P., Barceló, M., Barrio, J.A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., and Carmona, E.

Subjects
*TELESCOPES, *CRAB Nebula, *ATMOSPHERIC physics, *ZENITH distance, *SPECTRUM analysis, *GAMMA ray astronomy
Abstract

MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a series of upgrades, involving the exchange of the MAGIC-I camera and its trigger system, as well as the upgrade of the readout system of both telescopes. We use observations of the Crab Nebula taken at low and medium zenith angles to assess the key performance parameters of the MAGIC stereo system. For low zenith angle observations, the standard trigger threshold of the MAGIC telescopes is ∼ 50 GeV. The integral sensitivity for point-like sources with Crab Nebula-like spectrum above 220 GeV is (0.66 ± 0.03)% of Crab Nebula flux in 50 h of observations. The angular resolution, defined as the σ of a 2-dimensional Gaussian distribution, at those energies is ≲ 0.07°, while the energy resolution is 16%. We also re-evaluate the effect of the systematic uncertainty on the data taken with the MAGIC telescopes after the upgrade. We estimate that the systematic uncertainties can be divided in the following components: < 15% in energy scale, 11%–18% in flux normalization and ± 0.15 for the energy spectrum power-law slope. [ABSTRACT FROM AUTHOR]

Published
2016
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13. The major upgrade of the MAGIC telescopes, Part I: The hardware improvements and the commissioning of the system.

Author

Aleksić, J., Ansoldi, S., Antonelli, L.A., Antoranz, P., Babic, A., Bangale, P., Barceló, M., Barrio, J.A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., and Carmona, E.

Subjects
*TELESCOPES, *ATMOSPHERIC physics, *CHERENKOV radiation, *GAMMA ray astronomy, *ASTROPHYSICS periodicals
Abstract

The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. The telescopes are designed to measure Cherenkov light from air showers initiated by gamma rays in the energy regime from around 50 GeV to more than 50 TeV. The two telescopes were built in 2004 and 2009, respectively, with different cameras, triggers and readout systems. In the years 2011–2012 the MAGIC collaboration undertook a major upgrade to make the stereoscopic system uniform, improving its overall performance and easing its maintenance. In particular, the camera, the receivers and the trigger of the first telescope were replaced and the readout of the two telescopes was upgraded. This paper (Part I) describes the details of the upgrade as well as the basic performance parameters of MAGIC such as raw data treatment, linearity in the electronic chain and sources of noise. In Part II, we describe the physics performance of the upgraded system. [ABSTRACT FROM AUTHOR]

Published
2016
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14. Performance of the MAGIC stereo system obtained with Crab Nebula data

Author

Aleksić, J., Alvarez, E.A., Antonelli, L.A., Antoranz, P., Asensio, M., Backes, M., Barrio, J.A., Bastieri, D., Becerra González, J., Bednarek, W., Berdyugin, A., Berger, K., Bernardini, E., Biland, A., Blanch, O., Bock, R.K., Boller, A., Bonnoli, G., Borla Tridon, D., and Braun, I.

Subjects
*STEREOPHONIC sound systems, *CHERENKOV counters, *DATA analysis, *TELESCOPES, *STEREOSCOPIC views, *PERFORMANCE evaluation, *CRAB Nebula
Abstract

Abstract: MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma. Since autumn 2009 both telescopes have been working together in stereoscopic mode, providing a significant improvement with respect to the previous single-telescope observations. We use observations of the Crab Nebula taken at low zenith angles to assess the performance of the MAGIC stereo system. The trigger threshold of the MAGIC telescopes is 50−60GeV. Advanced stereo analysis techniques allow MAGIC to achieve a sensitivity as good as (0.76±0.03)% of the Crab Nebula flux in 50h of observations above 290GeV. The angular resolution at those energies is better than ∼0.07°. We also perform a detailed study of possible systematic effects which may influence the analysis of the data taken with the MAGIC telescopes. [Copyright &y& Elsevier]

Published
2012
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15. Investigating the peculiar emission from the new VHE gamma-ray source H1722+119

Author

M. Hayashida, M. Makariev, B. Biasuzzi, K. Mallot, R. J. García López, Louis Antonelli, D. Dominis Prester, E. Prandini, M. Doert, M. H. Wu, Massimo Persic, F. D'Ammando, Marc Ribó, G. Bonnoli, Abelardo Moralejo, Juri Poutanen, R. Reinthal, V. Fallah Ramazani, P. Bangale, Y. Hanabata, Razmik Mirzoyan, U. Barres de Almeida, Damir Lelas, T. Steinbring, Marina Manganaro, P. G. Prada Moroni, Stefano Covino, Hidetoshi Kubo, P. Antoranz, D. Galindo, J. Becerra González, G. Pedaletti, Dorota Sobczyńska, D. Nakajima, Thomas Bretz, J. Hose, Andrei Berdyugin, Pratik Majumdar, M. V. Fonseca, S. Bonnefoy, A. Sillanpää, Arka Chatterjee, Francesco Longo, D. Elsaesser, F. Di Pierro, K. Kodani, Alexander Hahn, Konstancja Satalecka, Walter Max-Moerbeck, Tomoki Saito, D. Tescaro, Ivica Puljak, Pierre Colin, H. Takami, L. Nogués, U. Menzel, Michele Doro, M. I. Martínez, Gareth Hughes, Talvikki Hovatta, C. Schultz, E. Moretti, Marcel Strzys, D. Fidalgo, Vassil Verguilov, Aaron Dominguez, Diego F. Torres, Julia Thaele, E. de Oña Wilhelmi, Reiko Orito, F. Verrecchia, Sabrina Einecke, Junko Kushida, P. Da Vela, R. López-Coto, J. Rodriguez Garcia, J. E. Ward, M. Palatiello, Elina Lindfors, A. Niedzwiecki, Kyoshi Nishijima, Ievgen Vovk, Wolfgang Rhode, Daniel Mazin, Oscar Blanch, Julian Sitarek, Juan Abel Barrio, L. Maraschi, Francesco Dazzi, David Paneque, A. Fernández-Barral, Markus Garczarczyk, Yusuke Konno, C. Fruck, B. De Lotto, M. Villata, T. Schweizer, T. Toyama, D. Guberman, Tomislav Terzić, K. Frantzen, J. L. Richards, Mosè Mariotti, A.-K. Overkemping, S. Paiano, Saverio Lombardi, Karl Mannheim, D. Hadasch, L. Perri, A. La Barbera, D. Eisenacher Glawion, X. Paredes-Fortuny, P. Temnikov, M. Nievas Rosillo, W. Idec, A. González Muñoz, E. Colombo, B. Banerjee, S. Buson, L. O. Takalo, Masahiro Teshima, Daniela Dorner, R. Zanin, Dariusz Gora, Adrian Biland, M. Gaug, J. Rico, J. Herrera, Koji Noda, Elisa Bernardini, A. De Angelis, A. Treves, Vitaly Neustroev, Jose Luis Contreras, Juan Cortina, G. Maneva, C. M. Raiteri, Nikola Godinovic, Benito Marcote, Max Ludwig Ahnen, Kari Nilsson, P. Giammaria, M. Will, Dario Hrupec, M. A. Lopez, R. Clavero, D. Garrido Terrats, W. Bednarek, Fabrizio Tavecchio, Ll. Font, I. Snidaric, Ana Babić, Stefano Ansoldi, Riccardo Paoletti, J. Palacio, J. M. Paredes, Antonio Stamerra, Alessandro Carosi, Jose Miguel Miranda, F. Borracci, Anthony C. S. Readhead, Universitat de Barcelona, Aalto-yliopisto, Aalto University, Ahnen ML, Ansoldi S, Antonelli LA, Antoranz P, Babic A, Banerjee B, Bangale P, de Almeida UB, Barrio JA, Gonzalez JB, Bednarek W, Bernardini E, Biasuzzi B, Biland A, Blanch O, Bonnefoy S, Bonnoli G, Borracci F, Bretz T, Buson S, Carosi A, Chatterjee A, Clavero R, Colin P, Colombo E, Contreras JL, Cortina J, Covino S, Da Vela P, Dazzi F, De Angelis A, De Lotto B, Wilhelmi ED, Di Pierro F, Doert M, Dominguez A, Prester DD, Dorner D, Doro M, Einecke S, Glawion DE, Elsaesser D, Ramazani VF, Fernandez-Barral A, Fidalgo D, Fonseca MV, Font L, Frantzen K, Fruck C, Galindo D, Lopez RJG, Garczarczyk M, Terrats DG, Gaug M, Giammaria P, Godinovic N, Munoz AG, Gora D, Guberman D, Hadasch D, Hahn A, Hanabata Y, Hayashida M, Herrera J, Hose J, Hrupec D, Hughes G, Idec W, Kodani K, Konno Y, Kubo H, Kushida J, La Barbera A, Lelas D, Lindfors E, Lombardi S, Longo F, Lopez M, Lopez-Coto R, Majumdar P, Makariev M, Mallot K, Maneva G, Manganaro M, Mannheim K, Maraschi L, Marcote B, Mariotti M, Martinez M, Mazin D, Menzel U, Miranda JM, Mirzoyan R, Moralejo A, Moretti E, Nakajima D, Neustroev V, Niedzwiecki A, Rosillo MN, Nilsson K, Nishijima K, Noda K, Nogues L, Orito R, Overkemping A, Paiano S, Palacio J, Palatiello M, Paneque D, Paoletti R, Paredes JM, Paredes-Fortuny X, Pedaletti G, Perri L, Persic M, Poutanen J, Moroni PGP, Prandini E, Puljak I, Rhode W, Ribo M, Rico J, Garcia JR, Saito T, Satalecka K, Schultz C, Schweizer T, Sillanpaa A, Sitarek J, Snidaric I, Sobczynska D, Stamerra A, Steinbring T, Strzys M, Takalo L, Takami H, Tavecchio F, Temnikov P, Terzic T, Tescaro D, Teshima M, Thaele J, Torres DF, Toyama T, Treves A, Verguilov V, Vovk I, Ward JE, Will M, Wu MH, Zanin R, DAmmando F, Berdyugin A, Hovatta T, Max-Moerbeck W, Raiteri CM, Readhead ACS, Reinthal R, Richards JL, Verrecchia F, Villata M, Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., Barres De Almeida, U., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Buson, S., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., De Oña Wilhelmi, E., Di Pierro, F., Doert, M., Domínguez, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher Glawion, D., Elsaesser, D., Fallah Ramazani, V., Fernández Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Giammaria, P., Godinović, N., González Muñoz, A., Gora, D., Guberman, D., Hadasch, D., Hahn, A., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Moretti, E., Nakajima, D., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nilsson, K., Nishijima, K., Noda, K., Nogués, L., Orito, R., Overkemping, A., Paiano, S., Palacio, J., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Pedaletti, G., Perri, L., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Saito, T., Satalecka, K., Schultz, C., Schweizer, T., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T, Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Verguilov, V., Vovk, I., Ward, J. E., Will, M., Wu, M. H., Zanin, R., D'Ammando, F., Berdyugin, A., Hovatta, T., Max Moerbeck, W., Raiteri, C. M., Readhead, A. C. S., Reinthal, R., Richards, J. L., Verrecchia, F., and Villata, M.

Subjects
galaxie [Gamma-rays], gamma-rays: galaxies, UPGRADE, Astrophysics, DETECTED BLAZARS, 01 natural sciences, LARGE-AREA TELESCOPE, law.invention, Raigs gamma, law, galaxies: active, BL Lacertae objects: individual: H1722+119, galaxies, distances and redshifts, BL LACERTAE OBJECTS, ALL-SKY SURVEY, MAGIC, TELESCOPES, LAC OBJECTS, SOURCE CATALOG, MAJOR, HELICAL JETS, CRAB-NEBULA, MAGIC (telescope), 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), distances and redshift [Galaxies], active BL Lacertae objects, individual, H1722+119 galaxies, distances and redshifts gamma-rays, Galaxies: active, Galaxies: distances and redshifts, Gamma-rays: galaxies, Astronomy and Astrophysics, Space and Planetary Science, galaxies [Gamma-rays], Extragalactic background light, Spectral energy distribution, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, BL Lac object, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Owens Valley Radio Observatory, Astrophysics::Cosmology and Extragalactic Astrophysics, Telescope, galaxies: active, BL Lacertae objects: individual: H1722+119, galaxies: distances and redshifts, gamma-rays: galaxies, 0103 physical sciences, individual: H1722+119 [BL Lacertae objects], distances and redshifts [Galaxies], ta115, 010308 nuclear & particles physics, Gamma rays, Astronomy, Astronomy and Astrophysic, Redshift, Crab Nebula, 13. Climate action, Galàxies actives, Active galaxies, ddc:520
Abstract

The MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescopes observed the BL Lac object H1722+119 (redshift unknown) for six consecutive nights between 2013 May 17 and 22, for a total of 12.5 h. The observations were triggered by high activity in the optical band measured by the KVA (Kungliga Vetenskapsakademien) telescope. The source was for the first time detected in the very high energy (VHE, $E > 100$ GeV) $\gamma$-ray band with a statistical significance of 5.9 $\sigma$. The integral flux above 150 GeV is estimated to be $(2.0\pm 0.5)$ per cent of the Crab Nebula flux. We used contemporaneous high energy (HE, 100 MeV $ < E < 100$ GeV) $\gamma$-ray observations from Fermi-LAT (Large Area Telescope) to estimate the redshift of the source. Within the framework of the current extragalactic background light models, we estimate the redshift to be $z = 0.34 \pm 0.15$. Additionally, we used contemporaneous X-ray to radio data collected by the instruments on board the Swift satellite, the KVA, and the OVRO (Owens Valley Radio Observatory) telescope to study multifrequency characteristics of the source. We found no significant temporal variability of the flux in the HE and VHE bands. The flux in the optical and radio wavebands, on the other hand, did vary with different patterns. The spectral energy distribution (SED) of H1722+119 shows surprising behaviour in the $\sim 3\times10^{14} - 10^{18}$ Hz frequency range. It can be modelled using an inhomogeneous helical jet synchrotron self-Compton model., Comment: 12 pages, 5 figures, 2 tables

Published
2016

16. The major upgrade of the MAGIC telescopes, Part I: The hardware improvements and the commissioning of the system

Author

R. Zanin, Adrian Biland, I. Lozano, J. Rico, Masahiro Teshima, W. Idec, Takashi Saito, J. Krause, B. De Lotto, Nikola Godinovic, Benito Marcote, Stefano Ansoldi, I. Snidaric, David Fink, K. Mallot, R. J. García López, D. Corti, Alessandro Carosi, Mosè Mariotti, A.-K. Overkemping, J. M. Illa, Riccardo Paoletti, Massimo Persic, Gianluca Giavitto, A. González Muñoz, Reiko Orito, P. Temnikov, M. Palatiello, J. Becerra González, Marcel Strzys, Dario Hrupec, M. Bitossi, Ruben Lopez-Coto, Jose Luis Lemus, D. Nakajima, Elina Lindfors, E. Lorenz, Abelardo Moralejo, Saverio Lombardi, A. Treves, Vitaly Neustroev, M. Makariev, Thomas Bretz, Daniel Mazin, Jose Miguel Miranda, M. A. Lopez, S. Rügamer, Juan Abel Barrio, S. Schmidl, T. Steinbring, Francesco Dazzi, J. M. Paredes, Antonio Stamerra, C. Delgado Mendez, G. Maneva, Stefano Covino, B. Biasuzzi, A. Dettlaff, M. Hayashida, D. Hildebrand, Francesco Longo, G. De Caneva, D. Fidalgo, Daniela Dorner, Jose Luis Contreras, Wolfgang Rhode, M. I. Martínez, Marc Ribó, S. Bonnefoy, K. Saito, Natalia Lewandowska, Patrick Vogler, E. Colombo, M. Gaug, Juan Cortina, D. Tescaro, Roberto Cecchi, P. Bangale, H. Wetteskind, A. La Barbera, A. Deangelis, J. Herrera, Hidetoshi Kubo, Sabrina Einecke, S. R. Gozzini, Luis Ángel Tejedor, M. V. Fonseca, Hanna Kellermann, Koji Noda, Louis Antonelli, G. Bonnoli, J. Rodriguez Garcia, Elisa Bernardini, X. Paredes-Fortuny, J. Hose, U. Menzel, K. Kodani, J. Storz, Yusuke Konno, Christian Fruck, A. Sillanpää, D. Elsaesser, L. O. Takalo, F. Borracci, W. Haberer, H. Takami, Oscar Blanch, K. Frantzen, P. G. Prada Moroni, Diego F. Torres, W. Bednarek, Fabrizio Tavecchio, V. Kadenius, S. Paiano, Ll. Font, D. Garrido Terrats, A. Lorca, Karl Mannheim, O. Tibolla, Alicia López-Oramas, T. Schweizer, Felix Spanier, R. Mirzoyan, P. Munar-Adrover, D. Eisenacher, V. Scalzotto, Markus Garczarczyk, N. Mankuzhiyil, Juri Poutanen, Kyoshi Nishijima, D. Dominis Prester, Y. Hanabata, C. Schultz, V. Scapin, P. Antoranz, M. L. Knoetig, Ana Babić, Julia Thaele, E. Carmona, Kari Nilsson, M. Will, L. Maraschi, E. Prandini, Tomislav Terzić, R. Reinthal, M. Negrello, Damir Lelas, Dorota Sobczyńska, Ivica Puljak, Pierre Colin, E. de Oña Wilhelmi, Jelena Aleksić, A. Niedzwiecki, David Paneque, M. Barcelo, D. Galindo, Konstancja Satalecka, Michele Doro, Julian Sitarek, Daniela Hadasch, T. Toyama, Junko Kushida, P. Da Vela, J. Schlammer, Universitat de Barcelona, Aleksić, J, Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barceló, M., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Cecchi, R., Colin, P., Colombo, E., Contreras, J. L., Corti, D., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., Deangelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Delgado Mendez, C., Dettlaff, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fidalgo, D., Fink, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Giavitto, G., Godinović, N., González Muñoz, A., Gozzini, S. R., Haberer, W., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Illa, J. M., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lemus, J. L., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorca, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Negrello, M., Neustroev, V., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Rügamer, S., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schlammer, J., Schmidl, S., Schweizer, T., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Tejedor, L. A., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Wetteskind, H., Will, M., and Zanin, R.

Subjects
Astrofísica, Physics::Instrumentation and Detectors, MAGIC, Imaging Atmospheric Cherenkov Telescopes, Instruments, TeV astrophysics, Very High Energy Gamma Rays, Stereoscopy, Astrophysics, 01 natural sciences, law.invention, Raigs gamma, law, Overall performance, MAGIC (telescope), TeV, astrophysics, CRAB-NEBULA, PERFORMANCE, STEREO, 010303 astronomy & astrophysics, Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Instrument, Upgrade, ddc:540, Electrónica, Física nuclear, Astrophysics::Earth and Planetary Astrophysics, Electricidad, Astrophysics - Instrumentation and Methods for Astrophysics, TeV astrophysic, Noise (radio), Computer hardware, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Telescope, 0103 physical sciences, Very High Energy Gamma Ray, Instrumentation and Methods for Astrophysics (astro-ph.IM), Cherenkov radiation, ta115, Telescopis, 010308 nuclear & particles physics, business.industry, Gamma rays, Cherenkov Telescope Array, Imaging Atmospheric Cherenkov Telescope, business, astro-ph.IM, Telescopes
Abstract

The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. The telescopes are designed to measure Cherenkov light from air showers initiated by gamma rays in the energy regime from around 50 GeV to more than 50 TeV. The two telescopes were built in 2004 and 2009, respectively, with different cameras, triggers and readout systems. In the years 2011-2012 the MAGIC collaboration undertook a major upgrade to make the stereoscopic system uniform, improving its overall performance and easing its maintenance. In particular, the camera, the receivers and the trigger of the first telescope were replaced and the readout of the two telescopes was upgraded. This paper (Part I) describes the details of the upgrade as well as the basic performance parameters of MAGIC such as raw data treatment, dead time of the system, linearity in the electronic chain and sources of noise. In Part II, we describe the physics performance of the upgraded system., 19 pages, 18 figures, accepted by Astroparticle Physics

Published
2016

17. The major upgrade of the MAGIC telescopes, Part II: A performance study using observations of the Crab Nebula

Author

MAGIC Collaboration, Aleksic, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barcelo, M., Barrio, J. A., Gonzalez, J. Becerra, Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Cecchi, R., Colin, P., Colombo, E., Contreras, J. L., Corti, D., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Wilhelmi, E. de Ona, Mendez, C. Delgado, Dettlaff, A., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fidalgo, D., Fink, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., Lopez, R. J. Garcia, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giavitto, G., Godinovic, N., Munoz, A. Gonzalez, Gozzini, S. R., Haberer, W., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Illa, J. M., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lemus, J. L., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Lorca, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Nakajima, D., Negrello, M., Neustroev, V., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribo, M., Rico, J., Garcia, J. Rodriguez, Rugamer, S., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schlammer, J., Schmidl, S., Schweizer, T., Shore, S. N., Sillanpaa, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Tejedor, L. A., Temnikov, P., Terzic, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Wetteskind, H., Will, M., Zanin, R., Aleksić, J, Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barceló, M., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Cecchi, R., Colin, P., Colombo, E., Contreras, J. L., Corti, D., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Delgado Mendez, C., Dettlaff, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fidalgo, D., Fink, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Giavitto, G., Godinović, N., González Muñoz, A., Gozzini, S. R., Haberer, W., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Illa, J. M., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lemus, J. L., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorca, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Negrello, M., Neustroev, V., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Rügamer, S., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schlammer, J., Schmidl, S., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Tejedor, L. A., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Wetteskind, H., Will, M., Zanin, R., and Universitat de Barcelona

Subjects
Astrofísica, Flux, Astrophysics, 01 natural sciences, Raigs gamma, MONTE-CARLO, Astrophysics::Solar and Stellar Astrophysics, MAGIC (telescope), 010303 astronomy & astrophysics, Physics, Crab nebula, Astrophysics::Instrumentation and Methods for Astrophysics, Gamma-ray astronomy, Púlsars, FLARES, ddc:540, Cherenkov telescopes, Astronomy and Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, IMAGES, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Crab Nebula, GAMMA-RAY EMISSION, CHERENKOV TELESCOPES, PULSAR, SYSTEM, ARRAYS, TEV, Pulsar, 0103 physical sciences, Angular resolution, Instrumentation and Methods for Astrophysics (astro-ph.IM), Zenith, Cherenkov radiation, Pulsars, ta115, Telescopis, 010308 nuclear & particles physics, Gamma rays, Astronomy, Cherenkov telescope, High Energy Physics::Experiment, astro-ph.IM, Telescopes
Abstract

MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a series of upgrades, involving the exchange of the MAGIC-I camera and its trigger system, as well as the upgrade of the readout system of both telescopes. We use observations of the Crab Nebula taken at low and medium zenith angles to assess the key performance parameters of the MAGIC stereo system. For low zenith angle observations, the standard trigger threshold of the MAGIC telescopes is ~50GeV. The integral sensitivity for point-like sources with Crab Nebula-like spectrum above 220GeV is (0.66+/-0.03)% of Crab Nebula flux in 50 h of observations. The angular resolution, defined as the sigma of a 2-dimensional Gaussian distribution, at those energies is < 0.07 degree, while the energy resolution is 16%. We also re-evaluate the effect of the systematic uncertainty on the data taken with the MAGIC telescopes after the upgrade. We estimate that the systematic uncertainties can be divided in the following components: < 15% in energy scale, 11-18% in flux normalization and +/-0.15 for the energy spectrum power-law slope., 21 pages, 25 figures, accepted for publication in Astroparticle Physics

Published
2016

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