相关论文: Feeding the active nucleus of NGC 1097
We discuss the long-term evolution of the broad double-peaked H alpha profile of the LINER/Seyfert 1 nucleus of NGC 1097. Besides the previously known variation of the relative intensities of the blue and red peaks, the profile has recently…
We study the evolution of the broad, double-peaked Halpha emission-line profile of the LINER/Seyfert 1 nucleus of NGC 1097, using 24 spectra obtained over a time span of 11 yrs - from 1991 Nov. through 2002 Oct. While in the first 5 yrs the…
The broad (FWHM ~ 10,000 km/s) double-peaked H{\alpha} profile from the LINER/Seyfert 1 nucleus of NGC 1097 was discovered in 1991, and monitored for the following 11 years. The profile showed variations attributed to the rotation of gas in…
We present new spectroscopic observations of the LINER (and now Seyfert 1) nucleus of NGC 1097, and discuss the evolution of its broad, double-peaked Balmer lines. When originally discovered in 1991, the red peak of the double-peaked…
Recent studies have suggested that the short-timescale ($\lesssim7$ days) variability of the broad ($\sim$10,000 km s$^{-1}$) double-peaked H$\alpha$ profile of the LINER nucleus of NGC1097 could be driven by a variable X-ray emission from…
We present observations of the double-peaked broad H$\alpha$ profile emitted by the active nucleus of NGC 7213 using the the Gemini South Telescope in 13 epochs between 2011 September 27 and 2013 July 23. This is the first time that the…
We report evidence for a recent burst of star formation located within 9 pc of the active nucleus of NGC 1097. The observational signatures of the starburst include UV absorption lines and continuum emission from young stars observed in a…
We present up to two decades of spectroscopic monitoring of the double-peaked broad Halpha emission lines of seven broad-line radio galaxies. These extremely broad, double-peaked lines are successfully modeled by emission from gas in the…
Near-infrared images of the prototype LINER / Seyfert 1 galaxy NGC 1097 observed with the Very Large Telescope (VLT) using adaptive optics disclose with unprecedented detail a complex central network of filamentary structure spiralling down…
We report on one of the brightest flux levels of the Seyfert 2 galaxy NGC 2992 ever observed in X-rays, on May 2019. The source has been monitored every few days from March 26, 2019 to December 14, 2019 by Swift-XRT, and simultaneous…
We present new observations in X-ray and optical/ultraviolet of the nucleus of NGC1097, known for the abrupt appearance of broad, double-peaked Balmer lines in its spectrum in 1991. These new observations are used to construct the spectral…
An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which arise from the outer regions of the accretion disk which fuels the AGN. The line profiles vary on timescales of 5--10 years. Our group has monitored a…
We present a model for the accretion flow around the supermassive black hole in the LINER nucleus of NGC 1097 which fits the optical to X-ray spectral energy distribution (SED). The X-ray segment of the SED is based on observations with the…
We investigate the central sub-arcsec region of the low-luminosity active galactic nucleus NGC 1052, using a high-angular resolution dataset that covers 10 orders of magnitude in frequency. This allows us to infer the continuum emission…
A panchromatic view of the star forming ring and feeding process in the central kpc of the galaxy NGC 1097 is presented. The assembled IR to UV images at $\sim$10 pc resolution allow us to characterise the population of circa 250 clusters…
The circumnuclear star-forming ring of the barred spiral galaxy NGC 1097 provides a unique laboratory to study star formation under extreme conditions. This work aims to derive the physical properties of the circumnuclear star-forming…
We investigate the X-ray spectrum, variability and the surrounding ionized bubble of NGC1313 X-2 to explore the physics of super-Eddington accretion. Beyond the Eddington luminosity, the accretion disk of NGC1313 X-2 is truncated at a large…
We consider the implications of recent infrared and radio observations of the nucleus of NGC 4258. There is no direct evidence that the nucleus has been steadily accreting on the viscous timescale of the outer masing disk, which is >~ 10^9…
We present Hubble Space Telescope far-UV spectra of 4 QSOs whose sightlines pass through the halo of NGC 1097 at impact parameters of 48 -165 kpc. NGC 1097 is a nearby spiral galaxy that has undergone at least two minor merger events, but…
An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which are thought to arise from the outer regions of the accretion disk which fuels the AGN. The line profiles are observed to vary on a characteristic…