The 2010 very high energy gamma-ray flare and 10 years of multi-wavelength observations of M87

• Autores: Abramowski, A.; Acero, F.; Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Balzer, A.; Barnacka, A.; Barres de Almeida, U.; Becherini, Y.; Becker, J.; Behera, B.; Bernlöhr, K.; Birsin, E.; Biteau, J.; Bochow, A.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Büsching, I.; Medina, Maria Clementina; Paredes, Josep Maria; Pichel, Ana Carolina; Nagai, H.; Perlman, E. S.; Steele, I. A.; Walker, R. C.; Wood, D. L.
• Año de publicación: 2012
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: galaxies: active; galaxies: individual (M 87); gamma rays: observations; galaxies:jets; nuclei
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

The giant radio galaxy M87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3-6)10^9Msum) provides a unique opportunity to investigate the origin of very high energy (VHE; E>100 GeV) gamma-ray emission generated in relativistic outflows and the surroundings of super-massive black holes. M87 has been established as a VHE gamma-ray emitter since 2006. The VHE gamma-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M87 by the MAGIC and VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE was detected triggering further observations at VHE (H.E.S.S.), X-rays (Chandra), and radio (43 GHz VLBA). The excellent sampling of the VHE gamma-ray light curve enables one to derive a precise temporal characterization of the flare: the single, isolated flare is well described by a two-sided exponential function with significantly dierent flux rise and decay times of rise d = (1:69 +- 0:30) days and decay d = (0:611 +- 0:080) days, respectively. While the overall variability pattern of the 2010 flare appears somewhat dierent from that of previous VHE flares in 2005 and 2008, they share very similar timescales (day), peak fluxes , and VHE spectra. 43 GHz VLBA radio observations of the inner jet regions indicate no enhanced flux in 2010 in contrast to observations in 2008, where an increase of the radio flux of the innermost core regions coincided with a VHE flare. On the other hand, Chandra X-ray observations taken 3 days after the peak of the VHE gamma-ray emission reveal an enhanced flux from the core (flux increased by factor 2; variability timescale < 2 days). The long-term (2001-2010) multi-wavelength (MWL) light curve of M87, spanning from radio to VHE and including data from HST, LT, VLA and EVN, is used to further investigate the origin of the VHE gamma-ray emission. No unique, common MWL signature of the three VHE flares has been identified. In the outer kpc jet region, in particular in HST-1, no enhanced MWL activity was detected in 2008 and 2010, disfavoring it as the origin of the VHE flares during these years. Shortly after two of the three flares (2008 and 2010), the X-ray core was observed to be at a higher flux level than its characteristic range (determined from more than 60 monitoring observations: 2002-2009). In 2005, the strong flux dominance of HST-1 could have suppressed the detection of such a feature. Published models for VHE gamma-ray emission from M87 are reviewed in the light of the new data.
Fil: Abramowski, A.. Universitat Hamburg; Alemania
Fil: Acero, F.. Université Montpellier II; Francia
Fil: Aharonian, F.. Max-Planck-Institut fur Kernphysik; Alemania. Dublin Institute for Advanced Studies; Irlanda. National Academy of Sciences of the Republic of Armenia; Armenia
Fil: Akhperjanian, A. G.. National Academy of Sciences of the Republic of Armenia; Armenia. Yerevan Physics Institute; Armenia
Fil: Anton, G.. Universitat Erlangen Nuremberg; Alemania
Fil: Balzer, A.. Universitat Erlangen Nuremberg; Alemania
Fil: Barnacka, A.. Centre D'etudes de Saclay; Francia. Nicolaus Copernicus Astronomical Center; Polonia
Fil: Barres de Almeida, U.. Durham University; Reino Unido
Fil: Becherini, Y.. Ruhr Universität Bochum; Alemania. Université Paris Diderot - Paris 7; Francia
Fil: Becker, J.. Ruhr Universität Bochum; Alemania
Fil: Behera, B.. Ruprecht Karls Universitat Heidelberg; Alemania
Fil: Bernlöhr, K.. Humboldt-Universität zu Berlin; Alemania. Max-Planck-Institut fur Kernphysik; Alemania
Fil: Birsin, E.. Humboldt-Universität zu Berlin; Alemania
Fil: Biteau, J.. École Polytechnique; Francia. Centre National de la Recherche Scientifique; Francia
Fil: Bochow, A.. Max-Planck-Institut fur Kernphysik; Alemania
Fil: Boisson, C.. Université Paris Diderot - Paris 7; Francia. Centre National de la Recherche Scientifique; Francia
Fil: Bolmont, J.. Université Pierre et Marie Curie; Francia. Université Denis Diderot Paris 7; Francia. Centre National de la Recherche Scientifique; Francia
Fil: Bordas, P.. Universitat Tubingen; Alemania
Fil: Brucker, J.. Universitat Erlangen Nuremberg; Alemania
Fil: Brun, F.. École Polytechnique; Francia. Centre National de la Recherche Scientifique; Francia
Fil: Brun, P.. Centre D'etudes de Saclay; Francia
Fil: Bulik, T.. The University of Warsaw; Polonia
Fil: Büsching, I.. Ruhr Universität Bochum; Alemania. North-West University; Sudáfrica
Fil: Medina, Maria Clementina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina
Fil: Paredes, Josep Maria. Universidad de Barcelona; España
Fil: Pichel, Ana Carolina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina
Fil: Nagai, H.. National Astronomical Observatory of Japan; Japón
Fil: Perlman, E. S.. University Boulevard; Estados Unidos
Fil: Steele, I. A.. Liverpool John Moores University; Reino Unido
Fil: Walker, R. C.. National Radio Astronomy Observatory; Estados Unidos
Fil: Wood, D. L.. Spece Sciences División. Naval Research Laboratory; Estados Unidos