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We present a detailed analysis of XMM-Newton X-ray spectra of the Narrow-Line Seyfert 1 galaxy Mrk 1044. We find robust evidence for a multi-phase, ultra-fast outflow, traced by four separate components in the grating spectrum. One component has high column density and ionization state, and is outflowing at 0.15c. The other three wind components have lower temperature, lower column density, and have outflow velocities 0.08c. This wind structure is strikingly similar to that found in IRAS 17020+4544, suggesting that stratified winds may be a common feature of ultra-fast outflows. Such structure is likely produced by fluid instabilities that form when the nuclear wind shocks the ambient medium. We show that in an energy-driven wind scenario, the wind in Mrk 1044 might carry enough energy to produce significant feedback on its host galaxy. We further discuss the implications of the presence of a fast wind in yet another NLS1 galaxy with high Eddington ratio., Comment: Accepted for publication in ApJ

High-resolution X-ray spectroscopy has advanced our understanding of the hot Universe by revealing physical properties like kinematics, temperature, and abundances of the astrophysical plasmas. Despite the technical and scientific achievements, the lack of scientific products at a level higher than count spectra is hampering full scientific exploitation of high-quality data. This paper introduces the Catalogue of Ionized Emission Lines Observed by the Reflection Grating Spectrometer (CIELO-RGS) onboard the XMM-Newton space observatory. The CIELO-RGS catalogue aims to facilitate the exploitation of emission features in the public RGS spectra archive, in particular, to perform the correlation between X-ray spectral diagnostics parameters with measurements at other wavelengths. This paper focuses on the methodology of catalogue generation, describing the automated line detection algorithm. A moderate sample (~2400 observations) of high-quality RGS spectra available at XMM-Newton Science Archive is used as our starting point. A list of potential emission lines is selected based on a multi-scale peak detection algorithm in a uniform and automated way without prior assumption on the underlying astrophysical model. The candidate line list is validated via spectral fitting with simple continuum and line profile models. We also compare the catalogue content with published literature results on a small number of exemplary sources. We generate a catalogue of emission lines ~12000 detected in ~1600 observations toward stars, X-ray binaries, supernovae remnants, active galactic nuclei, and groups and clusters of galaxies. For each line, we report the observed wavelength, broadening, energy and photon flux, and equivalent width, etc., accepted to A&A

We report the detection of high-amplitude X-ray flaring of the AGN HE 1136-2304, which is accompanied by a strong increase in the flux of the broad Balmer lines, changing its Seyfert type from almost type 2 in 1993 down to 1.5 in 2014. HE 1136-2304 was detected by the $\textit{XMM–Newton}$ slew survey at >10 times the flux it had in the $\textit{ROSAT}$ all-sky survey, and confirmed with $\textit{Swift}$ follow-up after increasing in X-ray flux by a factor of ~30. Optical spectroscopy with SALT shows that the AGN has changed from a Seyfert 1.95 to a Seyfert 1.5 galaxy, with greatly increased broad line emission and an increase in blue continuum AGN flux by a factor of >4. The X-ray spectra from $\textit{XMM–Newton}$ and $\textit{NuSTAR}$ reveal moderate intrinsic absorption and a high energy cutoff at ~100 keV. We consider several different physical scenarios for a flare, such as changes in obscuring material, tidal disruption events, and an increase in the accretion rate. We find that the most likely cause of the increased flux is an increase in the accretion rate, although it could also be due to a change in obscuration., MLP acknowledges financial support from the Science and Technology Facilities Council (STFC). This paper is based on observations taken with the SALT telescope. This work has been supported by DFG grant Ko 857/32-2. Based on observations with XMM–Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC, Italy) and the California Institute of Technology (USA). We would also like to thank Neil Gehrels for approving the Swift ToO requests, and the Swift science operation team for performing the observations.

Winds outflowing from Active Galactic Nuclei (AGNs) may carry significant amount of mass and energy out to their host galaxies. In this paper we report the detection of a sub-relativistic outflow observed in the Narrow Line Seyfert 1 Galaxy IRAS17020+4544 as a series of absorption lines corresponding to at least 5 absorption components with an unprecedented wide range of associated column densities and ionization levels and velocities in the range of 23,000-33,000 km/s, detected at X-ray high spectral resolution (E/Delta E ~1000) with the ESA's observatory XMM-Newton. The charge states of the material constituting the wind clearly indicate a range of low to moderate ionization states in the outflowing gas and column densities significantly lower than observed in highly ionized ultra fast outflows. We estimate that at least one of the outflow components may carry sufficient energy to substantially suppress star formation, and heat the gas in the host galaxy. IRAS17020+4544 provides therefore an interesting example of feedback by a moderately luminous AGN hosted in a spiral galaxy, a case barely envisaged in most evolution models, which often predict that feedback processes take place in massive elliptical galaxies hosting luminous quasars in a post merger phase., Comment: 8 pages, 3 figures, to appear on ApJ Letters

Context. Icy grains in the inner coma of a comet may play an important role in the energy balance and in the production of certain gas coma species. Their existence has therefore been assumed repeatedly to explain a variety of observed phenomena. However, owing to their extremely short life time no evidence for the presence of icy grains had been found in any active comet close to the Sun. Aims. We observed Comet 9P/Tempel 1 during the Deep Impact mission to look for phenomena induced by the impact. Methods. The comet was observed with the XMM-Newton Observatory. We used the EPIC camera for X-ray imaging and the Optical Monitor for monitoring in the ultraviolet and visible spectral range. Results. An outburst of the comet nucleus was observed as a result of the impact and the evolution of the coma was monitored in gas and dust. Our observations led to the first detection of icy grains in a comet at 1.5 AU from the Sun. Conclusions. We showed for the first time that the material ejected from the nucleus of a comet contains icy grains, even at small heliocentric distance.

We present the analysis of XMM-Newton observations of three X-ray weak quasars: PG 1001+054, PG 1535+547 and PG 2112+059. All objects are absorbed by ionized material showing high column densities, NH = 2.9 × 10 22 cm −2 to NH = 1.9 × 10 23 cm −2 , and ionization parameters, ξ = 147 erg cm s −1 to ξ = 542 erg cm s −1 . The spectra of PG 1535+547 require an additional partial covering by neutral material with a column density of NH ≈ 9 × 10 22 cm −2 at a covering factor of ≈0.96. The spectra of PG 1535+547 show systematic residuals in the energy range from ∼ 4k eV to∼6 keV, which are inconsistent with Kα-fluorescence-emission of neutral or ionized iron under the assumption of a Gaussian line profile. They can be described with a relativistic disk line (Laor) and establish therefore the second X-ray weak quasar with such a spectral characteristic. Our results together with the findings of Brinkmann et al. (2004, A&A, 414, 107) and Piconcelli et al. (2004a, MNRAS, 351, 161), indicate that warm absorbers characterized by high column densities and ionization parameters are typical of X-ray weak quasars. The occurrence of a variable relativistic broad Fe Kα fluorescence line in two out of the five well studied X-ray weak quasars might indicate a second general characteristic of the entire object class. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.

We report on an XMM-Newton Reflection Grating Spectrometer observation of the black hole candidate and Galactic microquasar GRS 1758-258. The source entered a peculiar "off/soft" state in late February, 2001, in which the spectrum softened while the X-ray flux -- and the inferred mass accretion rate -- steadily decreased. We find no clear evidence for emission or absorption lines in the dispersed spectra, indicating that most of the observed soft flux is likely from an accretion disk and not from a cool plasma. The accretion disk strongly dominates the spectrum in this lower-luminosity state, and is only mildly recessed from the marginally stable orbit. These findings may be difficult to explain in terms of advection-dominated accretion flow, or "ADAF" models. We discuss these results within the context of ADAF models, simultaneous two-flow models, and observed correlations between hard X-ray flux and jet production., 14 pages, 4 figures (3 in color), ApJ accepted Oct. 1 2001

The large amplitude of the variations of the Seyfert I Galaxy Fairall-9 between 1978 and 1991 make this Active Galaxy especially suitable for a combined study in terms of reverberation analysis and photoioniza- tion modeling over the velocity eld of the broad lines of its ultraviolet spectrum. We have combined our ultravio- let data with those available at other wavelengths to de- rive the intrinsic ionizing continuum and to compare the predictions of the photoionization models with the obser- vations. The UV continuum varies with a factor of 33 4 on a characteristic time scale of 182 days. The intrinsic spectral index UV-optical is = 0:07 0:02 and the optical variations do not lag behind the UV variations at the mean sampling interval of 96 days. In the near IR, the J band flux presents a direct extension of the UV-optical continuum (J UV = 0:07 0:05). Only at low flux levels is the 2 10 keV flux proportional to the UV contin- uum, at higher UV flux levels proportionality between the X-rays and the UV brightness breaks down. The con- tinuum spectral energy distribution (SED) of the nu- cleus supports the previously reported FIR-NIR excess associated with 0.02 M dust at a distance of some 400 100 light-days, as well as a soft X-ray excess, possi- bly associated with the reprocessing on an accretion disk of the hard X-rays emitted from a region above the disk. The presence of strong Fe Kline in the GINGA spec- tra of this galaxy does lend support to this model. Line prole variability has been used to isolate four gaussian line components, which are sucient to describe all lines at all levels of brightness in a consistent way: one nar- row (i.e. unresolved at the IUE resolution), and three broad components: a central (velocity same as the nar

A detailed emission-line decomposition has been made from 15 years of observations with the IUE satellite of the highly variable Seyfert 1 galaxy Fairall 9, allowing us to study the line variability as a function of velocity and continuum brightness. The variability over the different velocity domains of the broad lines has been related to the continuum variability over a large wavelength domain from the X-rays to the infrared. Clear delays were established between the redshifted and blueshifted parts of the lines in Lyα and C IV, with the red sides of the lines responding faster with no delay and the blue sides responding with a delay of some 230 days. The observed spectral variability behavior of the continuum has been used as input for photoionization model calculations and the combined constraints from the models and differences for gas at different velocities define the structure and motions in the BLR.

We present a detailed analysis of all the X-ray data taken by the XMM-Newton satellite of a small sample of five Seyfert 1 galaxies: ESO 359-G19, HE 1143-1810, CTS A08.12, Mkn 110, and UGC 11763. Our aim is to characterize the different components of the material that print the absorption and emission features in the X-ray spectra of these objects. The continuum emission was studied through the EPIC spectra taking advantage of the spectral range of these cameras. The high resolution RGS spectra were analyzed in order to characterize the absorbing features and the emission line features that arise in the spectra of these sources., Facultad de Ciencias Astronómicas y Geofísicas

Aims. The detailed analysis of all data taken by the XMM-Newton satellite of UGC11763 to characterize the different components that are emitting and absorbing radiation in the vicinity of the active nucleus. Methods. The continuum emission was studied through the EPIC spectra taking profit of the spectral range of these cameras. The high resolution RGS spectra were analyzed in order to characterize the absorbing features and the emission line features that arise in the spectra of this source. Results. A power law with a photon index \Gamma = 1.72^{+0.03}_{-0.01} accounts for the continuum emission of this source in the hard X-rays from 10 down to 1 keV. At lower energies, a black body model with kT= 0.100\pm 0.003 keV provides a good description of the observed soft excess. The absorption signatures in the spectra of UGC11763 are consistent with the presence of a two phase ionized material (log U=1.65^{+0.07}_{-0.08}; 2.6\pm 0.1 and log N_{H} = 21.2\pm 0.2; 21.51\pm 0.01 cm^{-2}, respectively) in the line of sight. The physical conditions found are consistent with the two phases being in pressure equilibrium. The low ionization component is more ionized than typically found for warm absorbers in other Seyfert 1 galaxies. There are also signatures of some emission lines: Ovii He$\alpha$(r), Ovii He$\alpha$(f), a blend of the Neix He$\alpha$ triplet and Fexviii at \lambda 17.5 \AA., Comment: 11 pages, 10 figures, accepted to be published by A&A

We present the results of the analysis of the hard band XMM-Newton spectra of the luminous, L(2-10keV)~3.4E+45 erg/s, radio-quiet quasar, E1821+643. Two emission features were observed in the 6-7 keV rest frame band, confirming previous Chandra detection of these structures. We interpret these features as two single emission lines, one consistent with the neutral Fe K-alpha line at 6.4 keV and the other most likely due to FeXXVI. If related to the quasar, the high-energy emission line should originate in highly ionised matter, i.e. the accretion disc or the clouds of the emission line regions. Alternatively, it may be related to the intergalactic medium of the rich galaxy cluster in which E1821+643 is embedded. A composite broad emission line in combination with an absorption line model, however, also fits the data well. We discuss the possible physical interpretations of the origin of these features., Comment: Accepted for publication in A&A, 7 pages and 7 figures

This paper reports on a partially simultaneous observation of the bright Seyfert 1 Galaxy Mrk590, performed by XMM-Newton and Chandra. The long exposure (~100 ks) allows to investigate with great detail the Fe K complex at 6-7 keV and the presence of soft X-ray spectral features. We have analysed XMM-Newton data from the European Photon Imaging Camera (EPIC) in the 0.5-12 keV band and from the Reflection Grating Spectrometer (RGS) in the 0.35-2.5 keV band, and data from the High Energy Transmission Gratings (HETGs) onboard Chandra. UV and optical data from the Optical Monitor (OM) onboard XMM-Newton are also included in the analysis. The broad band spectrum is well described by an unabsorbed power law and three unresolved Fe~K lines in the 6-7 keV range. The presence of a Compton reflection component and a narrow Fe K line at 6.4 keV is consistent with an origin via torus reflection. The ionised Fe lines at ~6.7 and 7 keV are instead most likely originated by scattering on a warm and ionised gas. The soft X-ray spectrum appears to be almost featureless due to the very bright continuum emission, except for one emission line identified as OVIII Ly alpha detected at ~19 Angstrom by both RGS and Chandra-MEG. The emerging picture consists of an active nucleus seen directly on a "clean" line of sight without intervening material, surrounded by photoionised circumnuclear gas at a high ionisation level. We also study three serendipitous sources in the field of view of Chandra and XMM-Newton. One of these sources may be identified with an ULX of L_{0.3-10 keV}~10^{40} ergs/s., Comment: 10 pages, 13 figures, accepted for publication on A&A including referee's comments

We present the extraction and processing of the IUE Low Dispersion spectra within the framework of the ESA “IUE Newly Extracted Spectra” (INES) System. Weak points of SWET, the optimal extraction implementation to produce the NEWSIPS output products (extracted spectra) are discussed, and the procedures implemented in INES to solve these problems are outlined. The more relevant modifications are: 1) the use of a new noise model, 2) a more accurate representation of the spatial profile of the spectrum and 3) a more reliable determination of the background. The INES extraction also includes a correction for the contamination by solar light in long wavelength spectra. Examples showing the improvements obtained in INES with respect to SWET are described. Finally, the linearity and repeatability characteristics of INES data are evaluated and the validity of the errors provided in the extraction is discussed. Sin financiación 1.630 JCR (1999) Q2, 16/36 Astronomy and Astrophysics UEM

We present the results of an intensive ultraviolet monitoring campaign on the Seyfert 1 galaxy NGC 4151, as part of an effort to study its short time-scale variability over a broad range in wavelength. The nucleus of NGC 4151 was observed continuously with the {\it International Ultraviolet Explorer} (IUE) for 9.3 days, yielding a pair of LWP and SWP spectra every $\sim$70 minutes, and during four-hour periods for 4 days prior to and 5 days after the continuous monitoring period. The sampling frequency of the observations is an order of magnitude higher than that of any previous UV monitoring campaign on a Seyfert galaxy. The continuum fluxes in bands from 1275 \AA\ to 2688 \AA\ went through four significant and well-defined ``events'' of duration 2 -- 3 days during the continuous monitoring period. We find that the amplitudes of the continuum variations decrease with increasing wavelength, which extends a general trend for this and other Seyfert galaxies to smaller time scales (i.e., a few days). The continuum variations in all of the UV bands are {\it simultaneous} to within an accuracy of about 0.15 days, providing a strict constraint on continuum models. The emission-line light curves show only one major event during the continuous monitoring (a slow rise followed by a shallow dip), and do not correlate well with continuum light curves over the (short) duration of the campaign, because the time scale for continuum variations is apparently smaller than the response times of the emission lines., Comment: 39 pages, LaTeX, including 7 PostScript figures; To appear in the ApJ (October 20, 1996) Vol. 470

Aims. We seek a comprehensive analysis of all the information provided by the XMM-Newton satellite of the four Seyfert 1 galaxies ESO 359-G19, HE 1143-1810, CTS A08.12, and Mrk 110, including the UV range, to characterize the different components that are emitting and absorbing radiation in the vicinity of the active nucleus. Methods. The continuum emission was studied through the EPIC spectra by taking advantage of the spectral range of these cameras. The high-resolution RGS spectra were analyzed to characterize the absorbing and emission line features that arise in the spectra of the sources. All these data, complemented by information in the UV, are analyzed jointly in order to achieve a consistent characterization of the observed features in each object. Results. The continuum emission of the sources can be characterized either by a combination of a power law and a black body for the weakest objects or by two power law components for the brightest ones. The continuum is not absorbed by neutral or ionized material in the line of sight to any of these sources. In all of them we have identified a narrow Fe-Kα line at 6.4 keV. In ESO 359-G19 we also find an Fexxvi line at about 7 keV. In the soft X-rays band, we identify only one Ovii line in the spectra of HE 1143-1810 and CTS A08.12, and two Ovii-Heα triplets and a narrow Oviii-Lyα emission line in Mrk 110. Conclusions. Not detecting warm material in the line of sight to the low state objects is due to intrinsically weaker or absent absorption in the line of sight and not to a low signal-to-noise ratio in the data. Besides this, the absence of clear emission lines cannot be fully attributed to dilution of those lines by a strong continuum., Facultad de Ciencias Astronómicas y Geofísicas

We present the data and initial results from a combined Hubble Space Telescope (HST)/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signal-to-noise ratios than were obtained in our previous multiwavelength monitoring of this galaxy in 1988-1989. IUE spectra were obtained once every 2 days for a period of 74 days beginning on 1993 March 14. During the last 39 days of this campaign, spectroscopic observations were also made with the HST Faint Object Spectrograph (FOS) on a daily basis. Ground-based observations, consisting of 165 optical spectra and 77 photometric observations (both CCD imaging and aperture photometry), are reported for the period 1992 October-1993 September, although many of the data are concentrated around the time of the satellite-based program. These data constitute a fifth year of intensive optical monitoring of this galaxy. In this contribution we describe the acquisition and reduction of all of the satellite and ground-based data obtained in this program. We describe in detail various photometric problems with the FOS and explain how we identified and corrected for various anomalies.

Mid-infrared images of the Seyfert 1 galaxy Mrk 279 obtained with the ISO satellite are presented together with the results of a one-year monitoring campaign of the 2.5-11.7 micron spectrum. Contemporaneous optical photometric and spectrophotometric observations are also presented. The galaxy appears as a point-like source at the resolution of the ISOCAM instrument, 4-5". The 2.5-11.7 micron average spectrum of the nucleus in Mrk 279 shows a strong power law continuum with a spectral index alpha = -0.80+/-0.05 and weak PAH emission features. The Mrk 279 spectral energy distribution shows a mid-IR bump, which extends from 2 to 15-20 micron . The mid-IR bump is consistent with thermal emission from dust grains at a distance of >= 100 light-days. No significant variations of the mid-IR flux have been detected during our observing campaign, consistent with the relatively low amplitude (~10 % rms) of the optical variability during the campaign. The time delay for the Hbeta line emission in response to the optical continuum variations is 16.7 +5.3/5.6 days, consistent with previous measurements., In press in Astronomy and Astrophysics (main journal) 12 pages, 5 figures