Search Results - "Seyfert galaxies"

Radio and X-ray variability in the Seyfert galaxy NGC 4051 by Jones, S., McHardy, I., Moss, D., Seymour, Nick, Breedt, E., Uttley, P., Körding, E., Tudose, V.

“…These percentage variations are similar to those of the Seyfert galaxy NGC 5548, which is 10 times brighter. Even if the radio variations in NGC 4051 are real, the percentage variability is much less than in the X-ray band. …”
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Galaxy Zoo: evidence for rapid, recent quenching within a population of AGN host galaxies by Smethurst, Rebecca J., Lintott, C.J., Simmons, B.D., Schawinski, K., Bamford, S.P., Cardamone, C.N., Kruk, S.J., Masters, K.L., Urry, C.M., Willett, K.W., Wong, O.I.

Subjects: “…galaxies: active ; galaxies: evolution ; galaxies: photometry ; galaxies: Seyfert ; galaxies: statistics…”
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Global e-VLBI observations of the gamma-ray narrow line Seyfert 1PMN J0948+0022 by Giroletti, M., Paragi, Z., Bignall, H., Doi, A., Foschini, L., Gabányi, K. É., Reynolds, C., Blanchard, J., Campbell, R. M., Colomer, F., Hong, X., Kadler, M., Kino, M., van Langevelde, H. J., Nagai, H., Phillips, C., Sekido, M., Szomoru A., Tzioumis A. K.

Subjects: “…galaxies: active / galaxies: Seyfert / galaxies: jets / instrumentation: high angular resolution / instrumentation: interferometers…”
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The AT20G view of swift/BAT selected AGN: High-frequency radio waves meet hard X-rays by Burlon, D., Ghirlanda, G., Murphy, T., Chhetri, Rajan, Sadler, E., Ajello, M.

“…We cross-matched the 6-year Swift/Burst Alert Telescope (BAT) survey of active galactic nuclei (AGN) with the AT20G radio survey of the southern sky, which is one of the largest high-frequency radio surveys available.With these datawe investigated the possible correlation between the radio and the X-ray emission at the highest radio and X-ray frequencies.We found 37AGNwith a high probability of association (>80 per cent), among which 19 are local Seyfert galaxies (with median redshift z=0.03) and 18 blazars.We found that˜20 per cent of theAGN detected in hard X-rays are also bright radio sources at 20 GHz, but the apparent correlation between the radio and hard X-ray luminosity is completely driven by the different median redshifts of the two subgroups of AGN. …”
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The Spitzer mid-infrared active galactic nucleus survey. I. Optical and near-infrared spectroscopy of obscured candidates and normal active galactic nuclei selected in the mid-infr... by Lacy, M., Ridgway, S., Gates, E., Nielsen, D., Petric, A., Sajina, A., Urrutia, T., Cox Drews, S., Harrison, C., Seymour, Nick, Storrie-Lombardi, L.

“…This survey selects both normal and obscured AGNs closely matched in luminosity across a wide range, from Seyfert galaxies with bolometric luminosities L bol ~ 1010 L ☉ to highly luminous quasars (L bol ~ 1014 L ☉), all with redshifts ranging from 0 to 4.3. …”
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