Results 51 to 60 of about 200 (175)

On X‐Ray Variability in Seyfert Galaxies [PDF]

The Astrophysical Journal, 1999
11 pages, 1 figure 1 table. LaTeX with encapsulated postscript. Accepted for publication in the Astrophysical Journal. Replaced first version to fix a printing problem caused by the figure.
Turner, T. J., George, I. M., Nandra, K., Turcan, D.   +3 more
openaire   +2 more sources

HNC, HCN and CN in Seyfert galaxies [PDF]

Astronomy & Astrophysics, 2007
Accepted for publication in A&A. A selection of this paper will be presented as a poster in the FIR workshop 2007, held at Bad Honnef, Germany. High resolution figures in original paper.
Perez-Beaupuits, J. P., Aalto, S., Gerebro, H.   +2 more
openaire   +3 more sources

Compact radio cores in Seyfert galaxies [PDF]

The Astrophysical Journal, 1994
We have observed a sample of 157 Seyfert galaxies with a 275 km baseline radio interferometer to search for compact, high brightness temperature radio emission from the active nucleus. We obtain the surprising result that compact radio cores are much more common in Seyfert 2 than in Seyfert 1 galaxies, which at first seems to be inconsistent with ...
Roy, A. L., Norris, R. P., Kesteven, M. J., Troup, E. R., Reynolds, J. E.   +4 more
openaire   +2 more sources

Hidden starbursts in Seyfert 1 galaxies [PDF]

Monthly Notices of the Royal Astronomical Society, 2003
5 pages, 1 figure.
Rodriguez-Ardila, A., Viegas, S.
openaire   +2 more sources

CO in Seyfert Galaxies [PDF]

Symposium - International Astronomical Union, 1989
We present data for Seyfert and normal galaxies in the Revised Shapley-Ames Catalog. The type 2 Seyferts are stronger CO and Far-IR emitters (by factors of 2–4) than either normal galaxies or type 1 Seyferts. The Seyfert CO line-widths correlate with both the 21cm HI and [OIII]5007 line-widths.
openaire   +1 more source

Effects of the environment on the properties of Seyfert galaxies [PDF]

Proceedings of the International Astronomical Union, 2004
We identify 175 Seyfert galaxies from the Southern Sky Redshift Survey - SSRS2. We use the entire SSRS2 catalog to investigate the correlation between the presence of AGN with host environment. The AGN phenomenon is more strongly correlated with the internal host properties, than with the external environment.
Maia, Marcio A. G., Willmer, Christopher N. A., Rossetto, Bruno M., Machado, Rodolfo S.   +3 more
openaire   +2 more sources

Astrophysical Journal Supplement Series

, 2014
We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (greater than or equal to0.1 counts s(-1)similar to 10(-12) ergs cm(-2) s(-1) in the 0.1-2.4 ...
Condon, J. J., Bauer, F. E., Broderick, John J., Thuan, T. X.   +3 more
core   +1 more source

The central parsec of NGC 3783: a rotating broad emission line region, asymmetric hot dust structure, and compact coronal line region

, 2021
International audienceUsing VLTI/GRAVITY and SINFONI data, we investigate the subparsec gas and dust structure around the nearby type 1 active galactic nucleus (AGN) hosted by NGC 3783. The K-band coverage of GRAVITY uniquely allows simultaneous analysis
Tristram, K., Peterson, B., Brandner, W., Förster Schreiber, N. M., Shangguan, J., Fellenberg, S., Bolzer, M., GRAVITY Collaboration, Sanchez-Bermudez, J., Lutz, D., Förster Schreiber, N.M., Drescher, A., Zeeuw, P.T. de, Tristram, K. R. W., Tristram, K.R.W., Petrucci, P., Davies, R., Schartmann, M., Widmann, F., Amorim, A., Ott, T., Shimizu, T., Straubmeier, C., Tacconi, L.J., Rouan, D., GRAVITY Collaboration,, Millour, F., Netzer, H., Garcia, P. J. V., Kishimoto, M., Peterson, B. M., Genzel, R., Hönig, S., Perrin, G., Tacconi, L., Gao, F., Clénet, Y., Sturm, E., Pfuhl, O., Straub, O., Förster Schreiber, N., Petrucci, P.O., Prieto, M. A., Perraut, K., Eckart, A., Bauböck, M., de Zeeuw, P. T., Petrucci, P. O., Paumard, T., Sternberg, A., Woillez, J., Vermot, P., de Zeeuw, P., Gillessen, S., Kaltenbrunner, D., Eisenhauer, F., Garcia, P., Lacour, S., Prieto, M.A., Stadler, J., von Fellenberg, S., Tacconi, L. J., Prieto, M., Waisberg, I., Gratadour, D., Dexter, J., Peterson, B.M., de Zeeuw, P.T., Garcia, P.J.V.   +68 more
core   +2 more sources

Moti radiali nella Narrow Line Region delle galassie di Seyfert [PDF]

, 2022
I profili asimmetrici delle righe di [O III] λλ4959,5007 e i loro spostamenti dalla lunghezza d'onda di laboratorio, osservati nella gran parte degli spettri dei Nuclei Galattici Attivi (AGN), sono da anni motivo studio.
Zebellin, Stefano
core  

COMPTEL upper limits for Seyfert galaxies

AIP Conference Proceedings, 1994
The gamma‐ray emission of Seyfert galaxies has fallen far short of pre‐GRO expectations. No single object of this class has been detected by either COMPTEL or EGRET, and OSSE has detected only a fraction of the Seyferts expected. To derive a more stringent upper limit to the emission from these objects in the energy ranges 0.75 to 1 and 1 to 3 MeV, we ...
Maisack, M, Collmar, W, Lichti, G G, Schonfelder, V, Steinle, H, Bloemen, H, Hermsen, W, McConnell, Mark L, Stacy, G, Barr, P, Williams, O R   +10 more
openaire   +4 more sources