Zobrazeno 1 - 10
of 278
pro vyhledávání: '"Riffel, R A"'
Autor:
Bierschenk, M., Ricci, C., Temple, M. J., Satyapal, S., Cann, J., Xie, Y., Diaz, Y., Ichikawa, K., Koss, M. J., Bauer, F. E., Rojas, A., Kakkad, D., Tortosa, A., Ricci, F., Mushotzky, R., Kawamuro, T., Gupta, K. K., Trakhtenbrot, B., Chang, C. S., Riffel, R., Oh, K., Harrison, F., Powell, M., Stern, D., Urry, C. M.
We analyze the Spitzer spectra of 140 active galactic nuclei (AGN) detected in the hard X-rays (14-195 keV) by the Burst Alert Telescope (BAT) on board Swift. This sample allows us to probe several orders of magnitude in black hole masses ($10^6-10^9
Externí odkaz:
http://arxiv.org/abs/2409.17334
Autor:
Dors, O. L., Almeida, G. C., Oliveira, C. B., Flury, S. R., Riffel, R., Riffel, R. A., Cardaci, M. V., Hägele, G. F., Ilha, G. S., Krabbe, A. C., Arellano-Córdova, K. Z., Santos, P. C., Morais, I. N.
For the first time, a calibration between the HeI $\lambda5876$/H$\beta$ emission line ratio and the helium abundance $y$=12+log(He/H) for Narrow line regions (NLRs) of Seyfert~2 Active Galactic Nuclei (AGN) is proposed. In this context, observationa
Externí odkaz:
http://arxiv.org/abs/2406.03259
Autor:
Dors, O. L., Cardaci, M. V., Hägele, G. F., Valerdi, M., Ilha, G. S., Oliveira, C. B., Riffel, R. A., Flury, S. R., Arellano-Córdova, K. Z., Storchi-Bergmann, T., Riffel, R., Almeida, G. C., Morais, I. N.
We derive the nitrogen and oxygen abundances in the Narrow Line Regions (NLRs) of a sample of 38 local ($z \: < \: 0.4$) Seyfert~2 nuclei. For that, we consider narrow optical emission line intensities and direct estimates of the electron temperature
Externí odkaz:
http://arxiv.org/abs/2405.13906
Cosmic metallicity evolution of Active Galactic Nuclei: Implications for optical diagnostic diagrams
Autor:
Dors, Oli L., Cardaci, M. V., Hagele, G. F., Ilha, G. S., Oliveira, C. B., Riffel, R. A., Riffel, R., Krabbe, A. C.
We analyze the validity of optical diagnostic diagrams relying on emission-lines ratios and in the context of classifying Active Galactic Nuclei (AGNs) according to the cosmic metallicity evolution in the redshift range 0 < z < 11.2. In this regard,
Externí odkaz:
http://arxiv.org/abs/2311.14026
Autor:
Dors, O. L., Valerdi, M., Riffel, R. A., Riffel, R., Cardaci, M. V., Hägele, G. F., Armah, M., Revalski, M., Flury, S. R., Freitas-Lemes, P., Amôres, E. B., Krabbe, A. C., Binette, L., Feltre, A., Storchi-Bergmann, T.
For the first time, the sulphur abundance relative to hydrogen (S/H) in the Narrow Line Regions of a sample of Seyfert 2 nuclei (Sy 2s) has been derived via direct estimation of the electron temperature. Narrow emission line intensities from the SDSS
Externí odkaz:
http://arxiv.org/abs/2302.12876
Autor:
Riffel, R. A., Storchi-Bergmann, T., Riffel, R., Bianchin, M., Zakamska, N. L., Ruschel-Dutra, D., Bentz, M. C., Burtscher, L., Crenshaw, D. M., Dahmer-Hahn, L. G., Dametto, N. Z., Davies, R. I., Diniz, M. R., Fischer, T. C., Harrison, C. M., Mainieri, V., Revalski, M., Rodriguez-Ardila, A., Rosario, D. J., Schonell, A. J.
Publikováno v:
MNRAS, 521, 1832 (2023)
We present the hot molecular and warm ionised gas kinematics for 33 nearby ($0.001\lesssim z\lesssim0.056$) X-ray selected active galaxies using the H$_2 2.1218 \mu$m and Br$\gamma$ emission lines observed in the K-band with the Gemini Near-Infrared
Externí odkaz:
http://arxiv.org/abs/2302.11324
Autor:
Cerqueira-Campos, F. C., Rodríguez-Ardila, A., Panda, S., Riffel, R., Dahmer-Hahn, L. G., Marinello, M.
Coronal-Line Forest Active Galactic Nuclei (CLiF AGN) are characterized by strong, high-ionization lines, which are in contrast to what is found in typical AGNs. Here, we carry out an infrared analysis aimed at understanding the spectral energy distr
Externí odkaz:
http://arxiv.org/abs/2306.12500
Autor:
Ilha, G. S., Riffel, R. A., Ricci, T. V., Rembold, S. B., Storchi-Bergmann, T., Riffel, R., Roy, N., Bundy, K., Nemmen, R., Schimoia, J. S., da Costa, L. N.
Red Geysers are quiescent galaxies with galactic scale ionised outflows, likely due to low-luminosity Active Galactic Nuclei (AGN). We used Gemini GMOS-IFU observations of the inner $\sim 1.0-3.0$ kpc of nine Red Geysers selected from the MaNGA surve
Externí odkaz:
http://arxiv.org/abs/2208.03383
Autor:
Dors, O. L., Valerdi, M., Freitas-Lemes, P., Krabbe, A. C., Riffel, R. A., Amôres, E. B., Riffel, R., Armah, M., Monteiro, A. F., Oliveira, C. B.
For the first time, the helium abundance relative to hydrogen (He/H), which relied on direct measurements of the electron temperature, has been derived in the narrow line regions (NLRs) from a local sample of Seyfert 2 nuclei. In view of this, optica
Externí odkaz:
http://arxiv.org/abs/2206.09836
Autor:
Deconto-Machado, A., Riffel, R. A., Ilha, G. S., Rembold, S. B., Storchi-Bergmann, T., Riffel, R., Schimoia, J. S., Schneider, D. P., Bizyaev, D., Feng, S., Wylezalek, D., da Costa, L. N., Nascimento, J. C. do, Maia, M. A. G.
Publikováno v:
A&A 659, A131 (2022)
We analyse the kinematics of 170 AGN host galaxies as compared to those of a matched control sample of non-active galaxies from the MaNGA survey in order to characterise and estimate the extents of the Narrow Line Region (NLR) and of the kinematicall
Externí odkaz:
http://arxiv.org/abs/2201.01690