Search Results - "de Almeida, U. Barres"

X-ray spectra, light curves and SEDs of blazars frequently observed by Swift by Giommi, Paolo, Perri, M, Capalbi, M, D’Elia, V, Barres de Almeida, U, Brandt, C H, Pollock, A M T, Arneodo, F, Di Giovanni, A, Chang, Y L, Civitarese, O, De Angelis, M, Leto, C, Verrecchia, F, Ricard, N, Di Pippo, S, Middei, R, Penacchioni, A V, Ruffini, R, Sahakyan, N, Israyelyan, D, Turriziani, S

“…ABSTRACT Blazars research is one of the hot topics of contemporary extragalactic astrophysics. That is because these sources are the most abundant type of…”
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The Mercedes water Cherenkov detector by Assis, P., Bakalová, A., Barres de Almeida, U., Brogueira, P., Conceição, R., De Angelis, A., Gibilisco, L., González, B. S., Guillén, A., La Mura, G., Mendes, L. M. D., Mendes, L. F., Pimenta, M., Shellard, R. C., Tomé, B., Vícha, J.

“…The concept of a small, single-layer water Cherenkov detector, with three photomultiplier tubes (PMTs), placed at its bottom in a 120 ∘ star configuration (…”
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Early X-Ray Flares in GRBs by Ruffini, R., Wang, Y., Aimuratov, Y., Almeida, U. Barres de, Becerra, L., Bianco, C. L., Chen, Y. C., Karlica, M., Kovacevic, M., Li, L., Fuksman, J. D. Melon, Moradi, R., Muccino, M., Penacchioni, A. V., Pisani, G. B., Primorac, D., Rueda, J. A., Shakeri, S., Vereshchagin, G. V., Xue, S.-S.

“…We analyze the early X-ray flares in the GRB "flare-plateau-afterglow" (FPA) phase observed by Swift-XRT. The FPA occurs only in one of the seven GRB…”
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Optical spectroscopy of blazars for the Cherenkov Telescope Array – II by 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, Lindfors, E

“…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…”
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Gamma-ray burst detection prospects for next generation ground-based VHE facilities by La Mura, G, Barres de Almeida, U, Conceição, R, De Angelis, A, Longo, F, Pimenta, M, Prandini, E, Ruiz-Velasco, E, Tomé, B

“…ABSTRACT Gamma-ray Bursts (GRB) were discovered by satellite-based detectors as powerful sources of transient γ-ray emission. The Fermi satellite detected an…”
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On the Rate and on the Gravitational Wave Emission of Short and Long GRBs by Ruffini, R., Rodriguez, J., Muccino, M., Rueda, J. A., Aimuratov, Y., Almeida, U. Barres de, Becerra, L., Bianco, C. L., Cherubini, C., Filippi, S., Gizzi, D., Kovacevic, M., Moradi, R., Oliveira, F. G., Pisani, G. B., Wang, Y.

“…On the ground of the large number of gamma-ray bursts (GRBs) detected with cosmological redshift, we classified GRBs in seven subclasses, all with binary…”
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Particle acceleration and magnetic field structure in PKS 2155−304: optical polarimetric observations by de Almeida, U. Barres, Ward, M. J., Dominici, T. P., Abraham, Z., Franco, G. A. P., Daniel, M. K., Chadwick, P. M., Boisson, C.

“…In this paper, we present multiband optical polarimetric observations of the very-high energy blazar PKS 2155−304 made simultaneously with a HESS/Fermi…”
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Free-free absorption in the nucleus of Cen A: evidences from 7-mm emission variability by Abraham, Z., Barres de Almeida, U., Dominici, T. P., Caproni, A.

“…The existence of free-free absorption in the nucleus of Cen A was suggested by Tingay & Murphy in 2001 as an explanation for the large value of the spectral…”
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Teraelectronvolt emission from the γ-ray burst GRB 190114C

“…Long-duration γ-ray bursts (GRBs) are the most luminous sources of electromagnetic radiation known in the Universe. They arise from outflows of plasma with…”
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Extreme- and high-synchrotron-peaked blazars at the limit of Fermi-LAT detectability: the γ-ray spectrum of 1BIGB sources by Arsioli, B, Barres de Almeida, U, Prandini, E, Fraga, B, Foffano, L

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The binary progenitors of short and long GRBs and their gravitational-wave emission by Rueda, J. A., Ruffini, R., Rodriguez, J. F., Muccino, M., Aimuratov, Y., Barres de Almeida, U., Becerra, L., Bianco, C. L., Cherubini, C., Filippi, S., Kovacevic, M., Moradi, R., Pisani, G. B., Wang, Y.

“…We have sub-classified short and long-duration gamma-ray bursts (GRBs) into seven families according to the binary nature of their progenitors. Short GRBs are…”
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LATTES: a new gamma-ray detector concept for South America by Assis, P., Barres de Almeida, U., Blanco, A., Conceição, R., D’Ettoree Piazzoli, B., De Angelis, A., Doro, M., Fonte, P., Lopes, L., Matthiae, G., Pimenta, M., Shellard, R., Tomé, B.

“…Currently the detection of Very High Energy gamma-rays for astrophysics rely on the measurement of the Extensive Air Showers (EAS) either using Cherenkov…”
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The RINGO2 and DIPOL optical polarization catalogue of blazars by Jermak, H., Steele, I. A., Lindfors, E., Hovatta, T., Nilsson, K., Lamb, G. P., Mundell, C., Barres de Almeida, U., Berdyugin, A., Kadenius, V., Reinthal, R., Takalo, L.

“…We present ∼2000 polarimetric and ∼3000 photometric observations of 15 γ-ray bright blazars over a period of 936 days (2008-10-11 to 2012-10-26) using data…”
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Multiwavelength variability and correlation studies of Mrk 421 during historically low X-ray and γ-ray activity in 2015–2016 by Acciari, V A, Antonelli, L A, Barrio, J A, Bellizzi, L, Bernardini, E, Besenrieder, J, Bhattacharyya, W, Bošnjak, Ž, Busetto, G, Ceribella, G, Cerruti, M, Contreras, J L, Covino, S, D’Elia, V, Da Vela, P, Delfino, M, Delgado Mendez, C, Di Girolamo, T, Di Pierro, F, Di Venere, L, Doro, M, Fallah Ramazani, V, Ferrara, G, Font, L, Fukami, S, García López, R J, Giglietto, N, Gliwny, P, Godinović, N, Green, J G, Hadasch, D, Hahn, A, Herrera, J, Hoang, J, Hütten, M, Inada, T, Inoue, S, Ishio, K, Kajiwara, Y, Karjalainen, M, Lamastra, A, Lombardi, S, Loporchio, S, Maggio, C, Makariev, M, Mallamaci, M, Manganaro, M, Maraschi, L, Mariotti, M, Miceli, D, Minev, M, Miranda, J M, Moralejo, A, Morcuende, D, Moreno, V, Neustroev, V, Nilsson, K, Ninci, D, Ohtani, Y, Palatiello, M, Persic, M, Prada Moroni, P G, Ribó, M, Rico, J, Righi, C, Rugliancich, A, Saha, L, Sahakyan, N, Sakurai, S, Satalecka, K, Schleicher, B, Schmidt, K, Schweizer, T, Sitarek, J, Strom, D, Strzys, M, Surić, T, Terzić, T, Torres-Albà, N, Ventura, S, Verguilov, V, Vigorito, C F, Vovk, I, Zarić, D, Baack, D, Biederbeck, N, Biland, A, Bretz, T, Bruegge, K, Buss, J, Dorner, D, Elsaesser, D, Neise, D, Neronov, A, Theissen, F, Valverde, J, Perri, M, Marscher, A P, Järvelä, E, Righini, S

“…ABSTRACT We report a characterization of the multiband flux variability and correlations of the nearby (z = 0.031) blazar Markarian 421 (Mrk 421) using data…”
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Constraining very-high-energy and optical emission from FRB 121102 with the MAGIC telescopes by Acciari, V A, Ansoldi, S, Antonelli, L A, Arbet Engels, 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, Berti, A, Besenrieder, J, Bhattacharyya, W, Bigongiari, C, Biland, A, Blanch, O, Bonnoli, G, Carosi, R, Ceribella, G, Chatterjee, A, Colak, S M, Colin, P, Colombo, E, Contreras, J L, Cortina, J, Covino, S, Cumani, P, D’Elia, V, Da Vela, P, Dazzi, F, De Angelis, A, De Lotto, B, Delfino, M, Delgado, J, Pierro, F Di, Domínguez, A, Dominis Prester, D, Dorner, D, Doro, M, Einecke, S, Elsaesser, D, Fallah Ramazani, V, Fattorini, A, Fernández-Barral, A, Ferrara, G, Fidalgo, D, Foffano, L, Fonseca, M V, Font, L, Fruck, C, Gallozzi, S, García López, R J, Garczarczyk, M, Gaug, M, Giammaria, P, Godinović, N, Guberman, D, Hadasch, D, Hahn, A, Hassan, T, Herrera, J, Hoang, J, Hrupec, D, Inoue, S, Ishio, K, Iwamura, Y, Kubo, H, Kushida, J, Kuveždić, D, Lamastra, A, Lelas, D, Leone, F, Lindfors, E, Lombardi, S, Longo, F, López, M, López-Oramas, A, Maggio, C, Majumdar, P, Makariev, M, Maneva, G, Manganaro, M, Mannheim, K, Maraschi, L, Mariotti, M, Martínez, M, Masuda, S, Mazin, D, Minev, M, Miranda, J M, Mirzoyan, R, Molina, E, Moralejo, A, Moreno, V, Moretti, E, Neustroev, V

“…Fast radio bursts (FRBs) are bright flashes observed typically at GHz frequencies with millisecond duration, whose origin is likely extragalactic. Their nature…”
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Search for a dark matter annihilation signal from the galactic center halo with H.E.S.S by Abramowski, A, Acero, F, Aharonian, F, Akhperjanian, A G, Anton, G, Barnacka, A, de Almeida, U Barres, Bazer-Bachi, A R, Becherini, Y, Becker, J, Behera, B, Bernlöhr, K, Bochow, A, Boisson, C, Bolmont, J, Bordas, P, Borrel, V, Brucker, J, Brun, F, Brun, P, Bulik, T, Büsching, I, Carrigan, S, Casanova, S, Cerruti, M, Chadwick, P M, Charbonnier, A, Chaves, R C G, Cheesebrough, A, Chounet, L-M, Clapson, A C, Coignet, G, Conrad, J, Dalton, M, Daniel, M K, Davids, I D, Degrange, B, Deil, C, Dickinson, H J, Djannati-Ataï, A, Domainko, W, Drury, L O'C, Dubois, F, Dubus, G, Dyks, J, Dyrda, M, Egberts, K, Eger, P, Espigat, P, Fallon, L, Farnier, C, Fegan, S, Feinstein, F, Fernandes, M V, Fiasson, A, Fontaine, G, Förster, A, Füssling, M, Gallant, Y A, Gast, H, Gérard, L, Gerbig, D, Giebels, B, Glicenstein, J F, Glück, B, Goret, P, Göring, D, Hague, J D, Hampf, D, Hauser, M, Heinz, S, Heinzelmann, G, Henri, G, Hermann, G, Hinton, J A, Hoffmann, A, Hofmann, W, Hofverberg, P, Horns, D, Jacholkowska, A, de Jager, O C, Jahn, C, Jamrozy, M, Jung, I, Kastendieck, M A, Katarzyński, K, Katz, U, Kaufmann, S, Keogh, D, Kerschhaggl, M, Khangulyan, D, Khélifi, B, Klochkov, D, Kluźniak, W, Kneiske, T, Komin, Nu, Kosack, K, Kossakowski, R, Laffon, H, Lamanna, G

“…A search for a very-high-energy (VHE; ≥100  GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards a region of projected…”
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Active Galactic Nuclei under the scrutiny of CTA by Sol, H., Zech, A., Boisson, C., Barres de Almeida, U., Biteau, J., Contreras, J.-L., Giebels, B., Hassan, T., Inoue, Y., Katarzyński, K., Krawczynski, H., Mirabal, N., Poutanen, J., Rieger, F., Totani, T., Benbow, W., Cerruti, M., Errando, M., Fallon, L., de Gouveia Dal Pino, E., Hinton, J.A., Inoue, S., Lenain, J.-P., Neronov, A., Takahashi, K., Takami, H., White, R.

“…Active Galactic Nuclei (hereafter AGN) produce powerful outflows which offer excellent conditions for efficient particle acceleration in internal and external…”
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Discovery of Very High Energy γ-Ray Emission from Centaurus a with H.E.S.S by Aharonian, F, Becherini, Y, Behera, B, Benbow, W, Boisson, C, Brucker, J, Brun, P, Bühler, R, Boutelier, T, Chaves, R. C. G, Coignet, G, Dalton, M, Daniel, M. K, Deil, C, Dickinson, H. J, Djannati-Ataï, A, Dyks, J, Dyrda, M, Emmanoulopoulos, D, Espigat, P, Farnier, C, Feinstein, F, Fiasson, A, Fontaine, G, Gallant, Y. A, Glicenstein, J.-F, Göhring, D, Hauser, D, Henri, G, Hermann, G, Hofmann, W, Horns, D, Jacholkowska, A, Katarzyński, K, Katz, U, Kaufmann, S, Kendziorra, E, Kerschhaggl, M, Khangulyan, D, Khélifi, B, Keogh, D, Kluźniak, W, Kneiske, T, Komin, Nu, Kosack, K, Lamanna, G, Lohse, T, Marandon, V, Martin, J. M, Marcowith, A, McComb, T. J. L, Moderski, R, Naumann-Godo, M, de Naurois, M, Nekrassov, D, Niemiec, J, Nolan, S. J, Ohm, S, Orford, K. J, Pedaletti, G, Pelletier, G, Petrucci, P.-O, Pühlhofer, G, Punch, M, Raue, M, Renaud, M, Rieger, F, Ripken, J, Rosier-Lees, S, Rowell, G, Rudak, B, Rulten, C. B, Ruppel, J, Sahakian, V, Schlickeiser, R, Schöck, F. M, Schwanke, U, Schwemmer, S, Shalchi, A, Sikora, M, Sol, H, Spangler, D, Stawarz, Ł, Steenkamp, R, Stegmann, C, Superina, G, Szostek, A, Terrier, R, Tluczykont, M, van Eldik, C, Venter, C, Venter, L, Vialle, J. P, Vincent, P, Vivier, M, Völk, H. J, Volpe, F, Wagner, S. J, Zdziarski, A. A, Zech, A

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Status of the Cherenkov Telescope Array project by Barres de Almeida, U.

“…Gamma‐ray astronomy holds a great potential for astro‐physics, particle physics, and cosmology. The CTA is an international initiative to build the next…”
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An intermittent extreme BL Lac: MWL study of 1ES 2344+514 in an enhanced state by Acciari, MAGIC Collaboration: V A, Ansoldi, S, Antonelli, L A, Babić, A, Banerjee, B, Barres de Almeida, U, Bellizzi, L, Bernardini, E, Berti, A, Bošnjak, Ž, Carosi, R, Chilingaryan, A, Colak, S M, Colin, U, Colombo, E, Cortina, J, D’Elia, V, Dazzi, F, De Lotto, B, Delgado, J, Di Venere, L, Donini, A, Fallah Ramazani, V, Ferrara, G, Font, L, Garczarczyk, M, Gasparyan, S, Giordano, F, Green, D, Hadasch, D, Hahn, A, Hoang, J, Hrupec, D, Hütten, M, Inada, T, Inoue, S, Kajiwara, Y, Kerszberg, D, Kobayashi, Y, Kushida, J, Lindfors, E, López-Coto, R, López-Oramas, A, Maggio, C, Majumdar, P, Mallamaci, M, Maraschi, L, Martínez, M, Mender, S, Mićanović, S, Miranda, J M, Molina, E, Moralejo, A, Morcuende, D, Moreno, V, Munar-Adrover, P, Neustroev, V, Nilsson, K, Ninci, D, Nishijima, K, Nogués, L, Ohtani, Y, Otero-Santos, J, Peresano, M, Persic, M, Prandini, E, Ribó, M, Rico, J, Righi, C, Sahakyan, N, Saito, T, Sakurai, S, Schmidt, K, Šnidarić, I, Sobczynska, D, Suda, Y, Tavecchio, F, Terzić, T, Teshima, M, Torres-Albà, N, van Scherpenberg, J, Vanzo, G, Ventura, S, Vitale, V, Vovk, I, Zarić, D, Beck, M, Blank, M, Bulinski, M, Doerr, M, Dorner, D, Iotov, R, Klinger, M, Mannheim, K, Achim Mueller, S, Neise, D, Neronov, A, Shukla, A, Acosta Pulido, MWL Collaborators: J, Readhead, A C S

“…ABSTRACT Extreme high-frequency BL Lacs (EHBL) feature their synchrotron peak of the broad-band spectral energy distribution (SED) at νs ≥ 1017 Hz. The BL Lac…”
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