Related papers: An Infrared Study of Centaurus A
We have used a near-infrared nuclear spectrum (covering the Z, J, H and K bands) of the nucleus of NGC 4151 obtained with the Gemini Near-infrared Integral Field Spectrograph (NIFS) and adaptive optics, to isolate and constrain the…
The non-thermal emission from the kiloparsec-scale jet of Centaurus A exhibits two notable features, bright diffuse emission and many compact knots, which have been intensively studied in X-ray and radio observations. H.E.S.S. recently…
Centaurus A, at a distance of less than 4 Mpc, is the nearest radio-loud AGN. Its emission is detected from radio to very-high energy gamma-rays. Despite the fact that Cen A is one of the best studied extragalactic objects the origin of its…
We used 13 years of Swift/BAT observations to probe the nature and origin of hard X-ray (14-195 KeV) emission in Centaurus A. Since the beginning of the Swift operation in 2004, significant X-ray variability in the 14-195 KeV band is…
Centaurus A (Cen A) is one of the most famous galaxies hosting an active galactic nucleus (AGN), where the interaction between AGN activities and surrounding interstellar and intergalactic media has been investigated. Recent studies…
We present near-infrared and millimeter investigations of the nucleus of the infrared luminous galaxy NGC 4418, which previous observations suggest possesses a powerful buried AGN. We found the following main results: (1) The infrared…
VLT J- to M\p-band adaptive optics observations of the Circinus Galaxy on parsec scales resolve a central bright Ks-band source with a FWHM size of 1.9 $\pm$ 0.6 pc. This source is only visible at wavelengths longward of 1.6 $\mu$m and…
We have determined the ratios of total to selective extinction in the near-infrared bands (J, H, Ks) toward the Galactic center from the observations of the region |l| < 2.0deg and 0.5deg < |b| < 1.0deg with the IRSF telescope and the…
An object discovered during an infrared survey of the field near the quasar B2 0149+33 has an emission line at 2.25$\mu$m that we interpret as H$\alpha$ at a redshift of 2.43. The K-band image shows two compact components 10 kpc apart…
We report the discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter in a deep 160 ks Suzaku XIS data. The emission is distributed over ~16x8 Jovian radius and spatially associated with the radiation belts and the Io Plasma…
We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively…
We present near-infrared spectra of the nuclear disk in the nearby radio galaxy NGC 5128 (Centaurus A). On the basis of the observed strengths of the [S III] 0.9532um and [Fe II] 1.2567um lines, we classify NGC 5128 as a LINER. Modeling of…
We used the Atacama Large Millimeter/Submillimeter Array (ALMA) to map the CO(3-2) and [CI](1-0) lines, as well as their underlying continuum emission, from the central $\sim 200$ pc region of the Circinus galaxy that hosts the nearest type…
We report Chandra ACIS-S3 x-ray imaging and spectroscopy of the R Aquarii binary system that show a spatially resolved two-sided jet and an unresolved central source. This is the first published report of such an x-ray jet seen in an…
We obtained observations of NGC 4639 with ASCA in order to investigate its mildly active Seyfert 1 nucleus at hard X-ray energies. Koratkar et al. (1995) have previously shown that the nucleus is a pointlike source in the ROSAT soft X-ray…
Due to the extreme extinction towards the Galactic centre ($A_{V} \sim 30$ mag), its stellar population is mainly studied in the near-infrared (NIR) regime. Therefore, a proper analysis of the NIR extinction curve is necessary to fully…
We present near-infrared integral field spectroscopy data obtained with VLT/SINFONI of "the Teacup galaxy". The nuclear K-band (1.95-2.45 micron) spectrum of this radio-quiet type-2 quasar reveals a blueshifted broad component of…
We present the first direct imaging of what may be the thick torus in the active galactic nucleus (AGN) of the archetype powerful radio galaxy Cygnus A, using the Jansky Very Large Array (VLA) at 18 GHz to 48 GHz, with a resolution down to…
We study the origin of non-thermal emissions from the Galactic black hole X-ray binary Cygnus X--1 which is a confirmed high mass microquasar. By analogy with those methods used in studies of active galactic nuclei, we propose a…
Here we present new optical data from the Hubble Space Telescope of the NGC 253 central region, which reveal numerous discrete sources in a ring--like structure. This is combined with data at infrared, millimeter, radio and X-ray…