B2 0954+25A, detected by the Fermi satellite, is a blazar with interesting observational properties: it has been observed to transit from a jet-dominated to a disc-dominated state; its radio spectrum appears flat at all observing frequencies (down to 74 MHz); optically, the H beta line profile is asymmetric. The flatness of the radio spectrum suggests that the isotropic emission from radio lobes is very weak, despite the large size of its jet. Its broad-band spectral energy distribution is surprisingly similar to that of the prototypical gamma-ray, radio-loud, type 1 narrow-line Seyfert (gamma-NLS1) galaxy PMN J0948+0022. In this work, we revisit the mass estimates of B2 0954+25A considering only the symmetric component of the H beta line and find 1-3 x 10^8 solar masses. In light of our composite analysis, we propose to classify the source as a transition object between the classes of flat spectrum radio quasars and gamma-NLS1 galaxies. A comparison with two members of each class (3C 273 and PMN J0948+0022) is discussed.

Calderone, G., Ghisellini, G., Colpi, M., & Dotti, M. (2012). B2 0954+25A: a typical Fermi blazar or a γ-ray loud Narrow Line Seyfert 1≟. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 424(4), 3081-3093 [10.1111/j.1365-2966.2012.21456.x].

B2 0954+25A: a typical Fermi blazar or a γ-ray loud Narrow Line Seyfert 1≟

CALDERONE, GIORGIO;COLPI, MONICA;DOTTI, MASSIMO
2012

Abstract

B2 0954+25A, detected by the Fermi satellite, is a blazar with interesting observational properties: it has been observed to transit from a jet-dominated to a disc-dominated state; its radio spectrum appears flat at all observing frequencies (down to 74 MHz); optically, the H beta line profile is asymmetric. The flatness of the radio spectrum suggests that the isotropic emission from radio lobes is very weak, despite the large size of its jet. Its broad-band spectral energy distribution is surprisingly similar to that of the prototypical gamma-ray, radio-loud, type 1 narrow-line Seyfert (gamma-NLS1) galaxy PMN J0948+0022. In this work, we revisit the mass estimates of B2 0954+25A considering only the symmetric component of the H beta line and find 1-3 x 10^8 solar masses. In light of our composite analysis, we propose to classify the source as a transition object between the classes of flat spectrum radio quasars and gamma-NLS1 galaxies. A comparison with two members of each class (3C 273 and PMN J0948+0022) is discussed.
No
Articolo in rivista - Articolo scientifico
Scientifica
galaxies: jets, quasars: individual: B2 0954+25A
English
3081
3093
13
Calderone, G., Ghisellini, G., Colpi, M., & Dotti, M. (2012). B2 0954+25A: a typical Fermi blazar or a γ-ray loud Narrow Line Seyfert 1≟. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 424(4), 3081-3093 [10.1111/j.1365-2966.2012.21456.x].
Calderone, G; Ghisellini, G; Colpi, M; Dotti, M
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Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/10281/37904
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