Results 31 to 40 of about 2,377,761 (195)

What powers the most relativistic jets? – II. Flat-spectrum radio quasars [PDF]

Monthly Notices of the Royal Astronomical Society, 2017
16 pages, 8 figures; accepted for publication in ...
Gardner, Emma, Done, Chris
openaire   +4 more sources

Flat Spectrum Radio Quasar Evolution and the Gamma-ray Background [PDF]

Proceedings of the International Astronomical Union, 2013
AbstractWe discuss an analysis of the redshift evolutions and distributions of the gamma-ray luminosity and photon spectral index of flat spectrum radio quasar (FSRQ) type blazars. We utilize data from the Fermi Gamma-ray Space Telescope, with redshfits as determined from optical spectroscopy by Shaw et al. We find that FSRQs have evolved significantly
Jack Singal, Allan Ko, Vahe Petrosian
openaire   +1 more source

Constraining the neutrino emission of gravitationally lensed Flat-Spectrum Radio Quasars with ANTARES data [PDF]

, 2014
This paper proposes to exploit gravitational lensing effects to improve the sensitivity of neutrino telescopes to the intrinsic neutrino emission of distant blazar populations.
Drouhin D, James C. W., Donzaud C, De Wolf E., Carr J, Samtleben D. F. E., Capone A, Vivolo D, Wilms J., Racca C, Michael T., Anton G., Vallage B., Fehn K, Gomez-Gonzalez J. P., Trovato A., Fehn K., Escoffier S., Hernandez-Rey J. J., Racca C., Schmid J., Andre M, Katz U, Bogazzi C, De Rosa G, Eberl T, Folger F, Mathieu A, Margiotta A., Gomez-Gonzalez JP, Biagi S., Perrina C., Stolarczyk Th., Loehner H, Falco EE, Roensch K., Bormuth R, Kadler M., Anton G, Visser E, Martinez-Mora J. A., Popa V, Yepes H., Dekeyser I, Hugon C, Bouwhuis MC, De Jong M., Geyer K, Schnabel J, Martini S., Guillard G., Caramete L., Geisselsoder S, Dornic D., Gay P., Mangano S, Fusco LA, Margiotta A, Tayalati Y, Wagner S., Hossl J., Elsasser D., Leonora E., Bormuth R., Dorosti Q, Heijboer AJ, Zuniga J., Biagii S, Bertin V, Coniglione R., Creusot A., Martinez-Mora JA, Gleixner A., Brunner J, de Wolf E, Core L, Busto J., Palioselitis D, Zornoza J. D., Circella M, Tamburini C, Wilms J, Dekeyser I., Richter R., Enzenhofer A., Samtleben DFE, Capone A., Heijboer A. J., Yatkin K, Distefano C., Lambard G., Chiarusi T, Yepes H, Bou-Cabo M, Sanchez-Losa A., Herrero A., Creusot A, Trovato A, Wagner S, Escoffier S, Drouhin D., Muller C, Martini S, Baret B., Galata S., Hernandez-Rey JJ, Bouwhuis M. C., Loehner H., Felis I., De Bonis G., Sanguineti M., Seitz T., Coyle P., Mangano S., Albert A., Dumas A., Migliozzi P, Schulte S., Richter R, Coyle P, Baret B, Barrios-Marti J, Schnabel J., Kreykenbohm I., Hossl J, Herold B., Vivolo D., Aubert J. -J., Yatkin K., De Bonis G, Kulikovskiy V., Stolarczyk T, de Jong M, Aubert JJ, James CW, Schulte S, Kalekin O., Distefano C, Kiessling D., Herrero A, Loucatos S, Tayalati Y., Vallage B, Rostovtsev A., Riccobene G., Kouchner A., Albert A, Kouchner A, Rostovtsev A, Sanguineti M, Andre M., Carr J., Dorosti Q., van Haren H, Lefevre D, Graf K, Katz U., Caramete L, Lahmann R, Hugon C., Seitz T, Dornic D, Deschamps A., Adrian-Martinez S, Graf K., Eberl T., Falco E. E., Ardid M., Kalekin O, Spies A., Neff M., Schussler F., Basa S., Gay P, Costantini H., Bertin V., Core L., Tonnis C, Guillard G, Galata S, Elsasser D, Perrina C, Leonora E, De Rosa G., Spurio M., Bruijn R, Dumas A, Hello Y, Sanchez-Losa A, Folger F., Bou-Cabo M., Lambard E., Kiessling D, Vallee C., Fermani P., Mathieu A., Taiuti M., Van Eewyck V, Haren H. V., Saldana M., Spies A, Lambard G, Geisselsoder S., Pradier T, Circella M., Fermani P, Kappes A., Enzenhofer A, Pradier T., Nezri E., Lambard E, Tselengidou M, Vallee C, Tamburini C., Michael T, Loucatos S., Riccobene G, Saldana M, Schussler F, Sieger C, Kooijman P., Marcelin M, Visser E., Migliozzi P., Ardid M, Lahmann R., Adrian-Martinez S., Palioselitis D., Neff M, Giordano V, Kreykenbohm I, Hofestadt J., Pavalas GE, Fusco L. A., Costantini H, Roensch K, Spurioi M, Gleixner A, Taiuti M, Barrios-Marti J., Brunner J., Zornoza JD, Bruijn R., Steijger JJM, Fells I, Herold B, Hello Y., Tselengidou M., Geyer K., Giordano V., Chiarusi T., Coniglione R, Busto J, Schmid J, Basa S, Zuniga J, Marcelin M., Steijger J. J. M., Popa V., Pevelas G. E., Hofestadt J, Sieger C., Kadler M, Kappes A, Deschamps A, Bogazzi C., Kooijman P, Lefevre D., Tonnis C., Nezri E, Kulikovskiy V, Muller C., Elewyck V. V., Donzaud C.   +273 more
core   +3 more sources

Implementation of spectrum sensing techniques for cognitive radio systems [PDF]

, 2011
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This work presents a method for real-time detection of secondary users at the cognitive wireless technologies base stations.
Radhi, Nazar Mortada
core   +7 more sources

Flat spectrum radio quasars: MAGIC results and unexpected features [PDF]

AIP Conference Proceedings, 2012
The detection of Flat Spectrum Radio Quasars (FSRQs) in the Very High Energy (VHE, E>100 GeV) range is challenging, mainly because of their steep soft spectra. Often neither the emission nor the variability features of recently discovered VHE-FSRQs can be explained with the models developed so far for BL Lacs.
De Caneva, G., Barres de Almeida, U., Stamerra, A., Tavecchio, F., Hayashida, M., MAGIC Collaboration, Fermi-LAT Collaboration, Becerra Gonzalez, J., Berger, K., Lindfors, E., Mazin, D., Paneque, D., Saito, K., Schultz, C., Sitarek, J.   +14 more
openaire   +2 more sources

The compact structure of radio-loud broad absorption line quasars

, 2008
We present the results of EVN+MERLIN very long baseline interferometry (VLBI) polarization observations of eight broad absorption line (BAL) quasars at 1.6 GHz, including four low-ionization BAL quasars (LoBALs) and four high-ionization BAL quasars ...
Xie, F. G., Wang, T. G., Liu, Y., Jiang, D. R.   +3 more
core   +1 more source

Spectral Energy Distributions of Flat‐Spectrum Radio Quasars Observed withBeppoSAX

The Astrophysical Journal, 2002
5 figures; ApJ, in ...
TAVECCHIO F., MARASCHI G., GHISELLINI G., Celotti, Anna Lisa, CHIAPPETTI L., COMASTRI A., FOSSATI G., GRANDI P., PIAN E., TAGLIAFERRI G., TREVES A., SAMBRUNA R. M.   +11 more
openaire   +5 more sources

The ultraviolet/optical variability of steep-spectrum radio quasars: the change in accretion rate?

, 2013
Context: The steep-spectrum radio quasars (SSRQs) are powerful radio sources, with thermal emission from accretion disk and jet nonthermal emission both likely contributing to the ultraviolet (UV)/optical luminosity; however, the former may play a ...
Gu, M. F., M. F. Gu, S.-L. Li, Li, S. -L.   +3 more
core   +1 more source

Multifrequency variability study of flat-spectrum radio quasar PKS 0346-27

Monthly Notices of the Royal Astronomical Society, 2023
ABSTRACT We have presented a multiwavelength temporal and spectral study of the blazar PKS 0346-27 for the period 2019 January–2021 December (MJD 58484–59575) using data from Fermi-LAT (γ-rays), Swift-XRT (X-rays), and Swift-UVOT (ultraviolet and optical).
Sushanth Reddy Kamaram, Raj Prince, Suman Pramanick, Debanjan Bose   +3 more
openaire   +2 more sources

Modelling the multi-wavelength emission of flat-spectrum radio quasar 3C 279 [PDF]

Monthly Notices of the Royal Astronomical Society, 2016
7 pages, 3 figures, published in MNRAS (2016MNRAS.457.3535Z)
Zheng, Y. G., Yang, C. Y.
openaire   +2 more sources