hrvatski jezikClear Cookie - decide language by browser settings

Detection of very high energy gamma-ray emission from NGC 1275 by the MAGIC telescopes

(MAGIC Collaboration) Aleksic, J.; Alvarez, E. A.; Antonelli, L. A.; Antoranz, P.; Asensio, M.; Backes, M.; de Almeida, U. Barres; Barrio, J. A.; Bastieri, D.; Becerra Gonzalez, J.; Bednarek, W.; Berger, K.; Bernardini, E.; Biland, A.; Blanch, O.; Bock, R. K.; Boller, A.; Bonnoli, G.; Tridon, D. Borla; Bretz, T.; Canellas, A.; Carmona, E.; Carosi, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Cossio, L.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Caneva, G.; del Pozo, E. De Cea; De Lotto, B.; Delgado Mendez, C.; Diago Ortega, A.; Doert, M.; Dominguez, A.; Prester, D. Dominis; Dorner, D.; Doro, M.; Eisenacher, D.; Elsaesser, D.; Ferenc, D.; Fonseca, M. V.; Font, L.; Fruck, C.; Garcia Lopez, R. J.; Garczarczyk, M.; Garrido, D.; Giavitto, G.; Godinovic, N.; Gozzini, S. R.; Hadasch, D.; Haefner, D.; Herrero, A.; Hildebrand, D.; Hoehne-Moench, D.; Hose, J.; Hrupec, D.; Huber, B.; Jogler, T.; Kadenius, V.; Kellermann, H.; Klepser, S.; Kraehenbuehl, T.; Krause, J.; La Barbera, A.; Lelas, D.; Leonardo, E.; Lewandowska, N.; Lindfors, E.; Lombardi, S.; Lopez, M.; Lopez-Coto, R.; Lopez-Oramas, A.; Lorenz, E.; Makariev, M.; Maneva, G.; Mankuzhiyil, N.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martinez, M.; Mazin, D.; Meucci, M.; Miranda, J. M.; Mirzoyan, R.; Moldon, J.; Moralejo, A.; Munar-Adrover, P.; Niedzwiecki, A.; Nieto, D.; Nilsson, K.; Nowak, N.; Orito, R.; Paiano, S.; Paneque, D.; Paoletti, R.; Pardo, S.; Paredes, J. M.; Partini, S.; Perez-Torres, M. A.; Persic, M.; Peruzzo, L.; Pilia, M.; Pochon, J.; Prada, F.; Moroni, P. G. Prada; Prandini, E.; Puerto Gimenez, I.; Puljak, I.; Reichardt, I.; Reinthal, R.; Rhode, W.; Ribo, M.; Rico, J.; Ruegamer, S.; Saggion, A.; Saito, K.; Saito, T. Y.; Salvati, M.; Satalecka, K.; Scalzotto, V.; Scapin, V.; Schultz, C.; Schweizer, T.; Shayduk, M.; Sillanpaa, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Spanier, F.; Spiro, S.; Stamatescu, V.; Stamerra, A.; Steinke, B.; Storz, J.; Strah, N.; Sun, S.; Suric, T.; Takalo, L.; Takami, H.; Tavecchio, F.; Temnikov, P.; Terzic, T.; Tescaro, D.; Teshima, M.; Tibolla, O.; Torres, D. F.; Treves, A.; Uellenbeck, M.; Vogler, P.; Wagner, R. M.; Weitzel, Q.; Zabalza, V.; Zandanel, F.; Zanin, R.; Pfrommer, C.; Pinzke, A.; (2012) Detection of very high energy gamma-ray emission from NGC 1275 by the MAGIC telescopes. Astronomy and Astrophysics, 539 . L2-1. ISSN 0004-6361

[img]
Preview
PDF - Accepted Version - article
Download (415kB) | Preview

Abstract

We report on the detection of very high energy (VHE, E > 100 GeV) gamma-ray emission from NGC 1275, the central radio galaxy of the Perseus cluster of galaxies. The source has been detected by the MAGIC telescopes with a statistical significance of 6.6 sigma above 100 GeV in 46 hr of stereo observations carried out between August 2010 and February 2011. The measured differential energy spectrum between 70 GeV and 500 GeV can be described by a power-law with a steep spectral index of Gamma = -4.1 +- 0.7stat +- 0.3syst, and the average flux above 100 GeV is F = (1.3 +- 0.2stat +- 0.3syst) x 10-11 cm-2 s-1. These results, combined with the power-law spectrum measured in the first two years of observations by the Fermi-LAT above 100 MeV, with a spectral index of Gamma ~= -2.1, strongly suggest the presence of a break or a cut-off around tens of GeV in the NGC 1275 spectrum. The light curve of the source above 100 GeV does not show hints of variability on month time-scale. Finally, we report on the non- detection in the present data of the radio galaxy IC 310, previously discovered by the Fermi-LAT and MAGIC. The derived flux upper limit F(U.L.) (> 300 GeV) = 1.2 x 10-12 cm-2 s-1 is a factor ~ 3 lower than the mean flux measured by MAGIC between October 2009 and February 2010, thus confirming the year time-scale variability of the source at VHE.

Item Type: Article
Uncontrolled Keywords: galaxies: active, galaxies: jets, galaxies: individual (NGC 1275), galaxies: individual (IC 310), gamma rays: galaxies
Subjects: NATURAL SCIENCES > Physics
NATURAL SCIENCES > Physics > Astronomy and Astrophysics
Divisions: Division of Experimental Physics
Projects:
Project titleProject leaderProject codeProject type
Photon-atom interaction and correlations (Foton-atom međudjelovanje i korelacije)-Tihomir Surić098-0982931-2875MZOS
UNSPECIFIEDUNSPECIFIED02.01/12MZOS
Depositing User: Dario Hrupec
Date Deposited: 16 Jan 2015 16:59
URI: http://fulir.irb.hr/id/eprint/1482
DOI: 10.1051/0004-6361/201118668

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year

Contrast
Increase Font
Decrease Font
Dyslexic Font
Accessibility