Results 21 to 30 of about 71 (64)

Blazar sequence – an artefact of Doppler boosting

, 2008
Context. The blazar sequence is a scenario in which the bolometric luminosity of the blazar governs the appearance of its spectral energy distribution.
M. Tornikoski, M. Kotiranta, E. Nieppola, T. Hovatta, E. Valtaoja   +4 more
core   +1 more source

Variable X-ray spectra of BL Lacertae objects - HEAO 1 observations of PKS 0548 - 322 and 2A 1219 + 305

, 1981
We present X-ray spectra for the BL Lac objects PKS 0548-322 and 2A 1219+305 measured with the HEAO 1 A-2 detectors during pointing maneuvers on 1978 September 30 and 1978 May 31, respectively.
Serlemitsos, P. J., Boldt, E. A., Holt, S. S., Mushotzky, R. F., Worrall, D. M.   +4 more
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Research and characterisation of blazar candidates among the Fermi/LAT 3FGL catalogue using multivariate classifications

, 2017
International audienceContext. In the recently published 3FGL catalogue, the Fermi/LAT collaboration reports the detection of γ-ray emission from 3034 sources obtained after four years of observations.
Lefaucheur, Julien, Pita, Santiago, Julien Lefaucheur, Santiago Pita   +3 more
core   +1 more source

Shocks in relativistic transverse stratified jets: A new paradigm for radio-loud AGN

, 2017
International audienceContext. The transverse stratification of active galactic nuclei (AGN) jets is suggested by observations and theoretical arguments, as a consequence of intrinsic properties of the central engine (accretion disc + black hole) and ...
Sauty, C., A. Zech, H. Sol, Meliani, Z., Z. Meliani, Boisson, C., Cayatte, V., C. Boisson, V. Cayatte, O. Hervet, Zech, A., C. Sauty, Hervet, O., Sol, H.   +13 more
core   +1 more source

The Pearson-Readhead survey of compact extragalactic radio sources from space II. Analysis of Source Properties

, 2001
We have performed a multidimensional correlation analysis on the observed properties of a statistically complete core-selected sample of compact radio-loud active galactic nuclei based on data from the VLBI Space Observing Programme (Paper I) and ...
Robert A. Preston (19105994), Mathew L. Lister (19106789), Steven J. Tingay (19015763)   +2 more
core   +1 more source

Long Term Observations of B2 1215+30 with Veritas

, 2013
We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E \u3e 100 GeV) by VERITAS with a significance of 8.9σ and showed clear variability on ...
Cui, W., Gyuk, G., Beilicke, M., Fortin, P., Gerard, L., Kieda, D., Holder, J., Feng, Q., Connolly, M. P., Khassen, Y., Griffin, S., Moriarty, P., Reynolds, P. T., Kertzman, M., Krawczynski, H., Majumdar, P., Arlen, T., Buckley, J. H., Gillanders, G. H., Dumm, J., Finley, J. P., Fortson, L., Madhavan, A. S., Aliu, E., Bouvier, A., Ciupik, L., Federici, S., Galante, N., Errando, M., Mukherjee, R., Archambault, S., McArthur, S., Furniss, A., Krennrich, F., Maier, G., Lang, M. J., Hanna, D., O’Faolain de Bhroithe, A., Hughes, G., McCann, A., Humensky, T. B., Aune, T., Cesarini, A., Falcone, A., Nieto, D., Bugaev, V., Bird, R., Kaaret, P., Benbow, W., Grube, J., Al, Et   +50 more
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Extragalactic background above GeV: Peaked BL lacertae objects or DM?

, 2008
Proceedings of the MPE/USM/MPA/ESO Joint Astronomy Conference Held in Munich, Germany, 7-11 November 2005K. Mannheim, D. Elsasser and T. Kneiskehttp://www.springer.com/astronomy/general+relativity/book/978-3-540-74712-
Mannheim, Karl, Elsasser, D., Kneiske, Tanja Manuela   +2 more
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Accretion properties and jet mechanisms for the low-excitation radio galaxies

Context. Radio galaxies (RGs) are a subclass of active galactic nuclei, which are suggested to be the parent populations of blazars. Based on morphologies and radio powers, RGs can be classified as Fanaroff-Riley type 0 (FR 0s), I (FR Is), and II (FR IIs)
Ranieri D. Baldi, Jun-Hui Fan, Denis Bastieri, Yong-Yun Chen, Xu-Hong Ye   +4 more
core   +1 more source

The evolution of dark matter substructure [PDF]

, 2001
This thesis investigates the dynamical evolution of systems orbiting within deeper potentials. Initially we use a simple satellite-halo interaction to study the dynamical processes that act on orbiting systems and we compare these results to analytical ...
Roldán, Carlos Antonio Calcáneo
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The development of a detector system for mint object spectroscopy on the Isaac Newton telescope [PDF]

, 1987
The work reported in this thesis describes the development of the CCD instrumentation for the Faint Object Spectrograph on the 2.5m Isaac Newton Telescope at the Observatorio del Roque de los Muchachos, more commonly known as the La Palma Observatory ...
Waltham, Nicholas Richard
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