相关论文: ASCA Observations of the Composite Warm Absorber i…

The Seyfert 1 galaxy, NGC3516 has been the subject of many absorption line studies at both ultraviolet and X-ray wavelengths. In the UV, strong, broad, variable associated metal line absorption with velocity width $\sim 2000$ \kms\ is…

We observed the Seyfert 1 galaxy NGC 3516 twice during the flight of Astro-2 using the Hopkins Ultraviolet Telescope in March 1995. Simultaneous X-ray observations were performed with ASCA. Our far-ultraviolet spectra cover the spectral…

A new Chandra observation and archival observations by ASCA are used to investigate spectral variations in the Sy1 galaxy NGC 3516 over a period of 7 years. A large change in flux (factor ~50 at 1keV) is observed between an ASCA observation…

We present two BeppoSAX observations of the bright Seyfert 1 galaxy NGC3516, performed four months apart (late 1996/early 1997). The earlier spectrum is considerably weaker and harder in the whole 0.1-50 keV energy range. In addition, the…

We present results from spectral analysis of ASCA data on the NLS1 Mrk 507. This galaxy was found to have an exceptionally flat ROSAT spectrum among the NLS1s. The ASCA spectrum however shows a clear absorption feature in the energy band…

We present data from simultaneous Chandra, XMM-Newton and BeppoSAX observations of the Seyfert 1 galaxy NGC 3516, taken during 2001 April and Nov. We have investigated the nature of the very flat observed X-ray spectrum. Chandra grating…

We have observed the broad-line radio galaxy Arp 102B with ASCA in order to determine the absorbing column density towards its X-ray source and measure its X-ray spectrum. The ultimate goal was to constrain the properties of the medium…

Results from the X-ray spectral analysis of the ASCA PV phase observation of the Seyfert 1 galaxy IC 4329A are presented. We find that the 0.4 - 10 keV spectrum of IC 4329A is best described by the sum of a steep ($\Gamma \sim 1.98$)…

We present observations of the UV absorption lines in the Seyfert 1 galaxy NGC 3516, obtained at a resolution of $\lambda$/$\Delta\lambda$ $\approx$ 40,000 with the Space Telescope Imaging Spectrograph (STIS) on 2000 October 1. The UV…

We present a detailed re-analysis of the two {\it ASCA} Performance Verification observations of the nearby Seyfert 1 galaxy MCG-6-30-15. Confirming the results of Fabian et al. (1994), we find definite evidence for the {\sc O\,vii} and…

ASCA X-ray spectral analysis of the Seyfert 2 galaxy IRAS 04575-7537 is presented. The main result is the presence of a significant iron edge at a rest energy of 7.13^+0.21_-0.16 keV. The spectrum is flat (Gamma = 1.5) with a substantial…

We present results from a 150 ksec Suzaku observation of the Seyfert 1.5 NGC 3516 in October 2005. The source was in a relatively highly absorbed state. Our best-fit model is consistent with the presence of a low-ionization absorber which…

We present a new analysis of the soft and medium energy X-ray spectrum of the Seyfert 1 galaxy NGC 3516 taken with the Reflection Grating Spectrometer (RGS) and European Photon Imaging Camera (EPIC) on board the XMM-Newton observatory. We…

We present a detailed analysis of the complex absorption apparent in the 2-6 keV X-ray spectrum of the bright nearby Seyfert galaxy NGC 4151. We first utilize the large bandpass and medium spectral resolution afforded by BeppoSAX data to…

This paper reports the X-ray spectral analysis of 5 high-redshift (z \ge 2) radio-quiet quasars observed by ASCA. A simple power law continuum plus cold Galactic absorption model well fits all the spectra (tipically between $\sim$ 2-30 keV…

We present a detailed analysis of broad band X-ray data of the Seyfert 2 galaxy NGC5506. 2-10 keV band are detected during a 1-day ASCA observation, while no significant change in the 2-10 keV continuum shape is found. The ASCA spectrum…

(Abridged) We present the results from a detailed analysis of the 0.6 - 10 keV spectra of 23 ASCA observations of 18 objects. We find that in most cases the underlying continuum can be well-represented by a powerlaw with a photon index…

We present simultaneous observations of the superluminal radio galaxy 3C120 performed with the ASCA and GRO (OSSE) satellites on February-March 1994, as well as an analysis of all the ROSAT archival data. The ASCA spectrum of this object…

We present results on the Seyfert 2 galaxy NGC4388 in the Virgo cluster observed with ASCA during its PV phase. The 0.5-10 keV X-ray spectrum consists of multiple components; (1) a continuum component heavily absorbed by a column density NH…

We present the results of two observations of the bright Seyfert 1 galaxy NGC 3516, obtained with BeppoSAX in 1996 November and 1997 March. Useful signal is detected between 0.2 and 60 keV, allowing for the first time the simultaneous…