ULTRAVIOLET AND X-RAY VARIABILITY OF THE SEYFERT 1.5 GALAXY MARKARIAN 817
نویسندگان
چکیده
منابع مشابه
X - ray absorption in the strong FeII narrow - line Seyfert 1 galaxy Markarian 507
We present results from spectral analysis of ASCA data on the strong Feii narrow-line Seyfert 1 galaxy Mrk 507. This galaxy was found to have an exceptionally flat ROSAT spectrum among the narrow-line Seyfert 1 galaxies (NLS1s) studied by Boller, Brandt & Fink (1996). The ASCA spectrum however shows a clear absorption feature in the energy band below 2 keV, which partly accounts for the flat sp...
متن کاملThe X-ray variability of the Seyfert 1 galaxy MCG 6-30-15 from long ASCA and RXTE observations
We present an analysis of the long Rossi X-ray Timing Explorer (RXTE ) observation of the Seyfert 1 galaxy MCG 6-30-15, taken in July 1997. We have earlier used the data to place constraints for the first time on the iron abundance reflection fraction relationship, and now expand the analysis to investigate in detail the spectral X-ray variability of the object. Our results show that the behavi...
متن کاملSimultaneous Ultraviolet and X-ray Observations of the Seyfert Galaxy NGC 4151. I. Physical Conditions in the X-ray Absorbers
We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 using Chandra/High Energy Transmission Grating Spectrometer data obtained 2002 May as part of a program which included simultaneous ultraviolet (UV) spectra using the Hubble Space Telescope/Space Telescope Imaging Spectrograph and the Far Ultraviolet Spectrographic Explorer. Previous studies, most ...
متن کاملSimultaneous Ultraviolet and X-ray Observations of Seyfert Galaxy Ngc 4151. I. Physical Conditions in the X-ray Absorbers
We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 usingChandraHigh Energy Transmission Grating Spectrometer data obtained in 2002 May as part of a program that included simultaneous ultraviolet (UV) spectra using theHubble Space TelescopeSpaceTelescope ImagingSpectrograph and theFarUltraviolet Spectrographic Explorer. Previous studies, most recent...
متن کاملThe X – ray spectrum and variability of the Seyfert 2 Galaxy NGC 7172
We present evidence of flux variability, on both short (hours) and long (months) time scales of the Seyfert 2 galaxy NGC 7172. These results are based on the ASCA observation of NGC 7172 performed on May 1996. The source was detected at a rather low flux level, about 3 times fainter than its usual state (including one year before, when it was also observed by ASCA). The source also varied by ab...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2011
ISSN: 0004-637X,1538-4357
DOI: 10.1088/0004-637x/728/1/28