Medical and Biomedical Researches

Very-High-Energy Gamma Rays from a Distant Quasar: How Transparent Is the Universe?

Very-High-Energy Gamma Rays from a Distant Quasar: How Transparent Is the Universe?

The atmospheric Cherenkov gamma-ray telescope MAGIC, designed for a low-energy threshold, has detected very-high-energy gamma rays from a giant flare of the distant Quasi-Stellar Radio Source (in short: radio quasar) 3C 279, at a distance of more than 5 billion light-years (a redshift of 0.536). No quasar has been observed previously in very-high-energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high-energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts.

The MAGIC Collaboration, Albert J, Aliu E, Anderhub H, Antonelli LA, Antoranz P, Backes M, Baixeras C, Barrio JA, Bartko H, Bastieri D, Becker JK, Bednarek W, Berger K, Bernardini E, Bigongiari C, Biland A, Bock RK, Bonnoli G, Bordas P, Bosch-Ramon V, Bretz T, Britvitch I, Camara M, Carmona E, Chilingarian A, Commichau S, Contreras JL, Cortina J, Costado MT, Covino S, Curtef V, Dazzi F, De Angelis A, De Cea Del Pozo E, de Los Reyes R, De Lotto B, De Maria M, De Sabata F, Mendez CD, Dominguez A, Dorner D, Doro M, Errando M, Fagiolini M, Ferenc D, Fernández E, Firpo R, Fonseca MV, Font L, Galante N, López RJ, Garczarczyk M, Gaug M, Goebel F, Hayashida M, Herrero A, Höhne D, Hose J, Hsu CC, Huber S, Jogler T, Kneiske TM, Kranich D, La Barbera A, Laille A, Leonardo E, Lindfors E, Lombardi S, Longo F, López M, Lorenz E, Majumdar P, Maneva G, Mankuzhiyil N, Mannheim K, Maraschi L, Mariotti M, Martínez M, Mazin D, Meucci M, Meyer M, Miranda JM, Mirzoyan R, Mizobuchi S, Moles M, Moralejo A, Nieto D, Nilsson K, Ninkovic J, Otte N, Oya I, Panniello M, Paoletti R, Paredes JM, Pasanen M, Pascoli D, Pauss F, Pegna RG, Perez-Torres MA, Persic M, Peruzzo L, Piccioli A, Prada F, Prandini E, Puchades N, Raymers A, Rhode W, Ribó M, Rico J, Rissi M, Robert A, Rügamer S, Saggion A, Saito TY, Salvati M, Sanchez-Conde M, Sartori P, Satalecka K, Scalzotto V, Scapin V, Schmitt R, Schweizer T, Shayduk M, Shinozaki K, Shore SN, Sidro N, Sierpowska-Bartosik A, Sillanpää A, Sobczynska D, Spanier F, Stamerra A, Stark LS, Takalo L, Tavecchio F, Temnikov P, Tescaro D, Teshima M, Tluczykont M, Torres DF, Turini N, Vankov H, Venturini A, Vitale V, Wagner RM, Wittek W, Zabalza V, Zandanel F, Zanin R, Zapatero J.

Universität Würzburg, D-97074 Würzburg, Germany.