相关论文: New Chandra/HST-STIS results on Seyfert I AGN: Pho…
We present the results of a uniform analysis of the soft X-ray spectra of fifteen type I AGN observed with the high resolution X-ray gratings on board \emph{Chandra}. We found that ten of the fifteen AGN exhibit signatures of an intrinsic…
In this paper, we analyze spectra of the Seyfert 1 galaxy NGC 4593 obtained with the Chandra Low Energy Transmission Grating Spectrometer (LETGS), the Reflection Grating Spectrometer (RGS) and the European Photon Imaging Camera's (EPIC)…
We present both phenomenological and more physical photoionization models of the Chandra HETG spectra of the Seyfert-1 AGN NGC 4051. We detect 40 absorption and emission lines, encompassing highly ionized charge states from O, Ne, Mg, Si, S…
High resolution X-ray spectroscopy of the warm absorber in the nearby X-ray bright Seyfert 1 galaxy, Mrk 1040 is presented. The observations were carried out in the 2013-2014 timeframe using the Chandra High Energy Transmission Grating with…
We observed the Seyfert 1 galaxy NGC 4593 with the Chandra high energy transmission gratings and present a detailed analysis of the soft X-ray spectrum. We measure strong absorption lines from He-like O, Ne, Mg, Si, H-like N, O, Ne, Mg, Si…
We present the results of a recent (March 2011) 160 ks Chandra-LETGS observation of the Seyfert galaxy NGC 4593, and the analysis of archival X-ray and UV spectra taken with XMM-Newton and HST/STIS in 2002. We find evidence of a…
We observed the Seyfert 1 galaxy Mrk 509 simultaneously with Chandra/HETG, HST/STIS and RXTE. We measure strong absorption lines from He-like Ne and Mg, and from H-like N, O, and Ne. The lines are unresolved except for Ne Lya and Ne IX(r).…
We present analysis and photoionization modeling of the Chandra high resolution spectrum of Mrk 279. There is clear evidence of an absorbing outflow which is best fit by a two component model, one with a low ionization parameter and one…
We present here the results of a 180 ks Chandra-LETGS observation as part of a large multi-wavelength campaign on Mrk 509. We study the warm absorber in Mrk 509 and use the data from a simultaneous HST-COS observation in order to assess…
Active Galactic Nuclei often show evidence of photoionized outflows. A major uncertainty in models for these outflows is the distance ($R$) to the gas from the central black hole. In this paper we use the HST/COS data from a massive…
Warm Absorbers (WAs), as an important form of AGN outflows, show absorption in both UV and X-ray band. Using XSTAR generated photoionization models, for the first time we present a joint fit to the simultaneous observations of HST/COS and…
We report on the detection of ultra-fast outflows in the Seyfert~1 galaxy Mrk 590. These outflows are identified through highly blue-shifted absorption lines of OVIII and NeIX in the medium energy grating spectrum and SiXIC and MgXII in the…
We present a time-resolved X-ray spectral analysis of the warm absorbers in the Seyfert galaxy NGC 4051, which has an active galactic nucleus (AGN), using observations from the Neutron Star Interior Composition Explorer (NICER). Despite…
We present a new method to model a HST/COS spectrum, aimed to analyze intrinsic UV absorption from the outflow of Mrk 290, a Seyfert I galaxy. We use newly updated XSTAR to generate photoionization models for the intrinsic absorption from…
We present in this paper the results of a 270 ks Chandra HETGS observation in the context of a large multiwavelength campaign on the Seyfert galaxy Mrk 509. The HETGS spectrum allows us to study the high ionisation warm absorber and the…
To investigate the origins of the warm absorbers in active galactic nuclei (AGNs), we study the ionization-state structure of the radiation-driven fountain model in a low-mass AGN (Wada et al. 2016) and calculate the predicted X-ray…
To understand the nature of transient obscuring outflows in active galactic nuclei, we observed the Seyfert 1 galaxy NGC 3783 on two occasions in December 2016 triggered by Swift monitoring indicating strong soft X-ray absorption in…
We present a detailed analysis of the intrinsic X-ray absorption in the Seyfert 1 galaxy NGC 4151 using Chandra/HETGS data obtained 2002 May, as part of a program which included simultaneous UV spectra using HST/STIS and FUSE. NGC 4151 was…
The Seyfert 1 galaxy 1H 0419-577 hosts a $\sim$kpc extended outflow that is evident in the [\ion{O}{iii}] image and that is also detected as a warm absorber in the UV/X-ray spectrum. Here, we analyze a $\sim$30 ks Chandra-ACIS X-ray image,…
We analyze the \textit{Chandra} High Energy Transmission Grating Spectrometer (HETGS) observation of the Seyfert $2$ AGN IRAS\,18325-5926. We detect a $v=-360^{+41}_{-66}$~km~s$^{-1}$ blueshifted ionized absorber in the X-ray spectrum, with…