UV Lines Research Articles

ELECTRON-IMPACT EXCITATION COLLISION STRENGTHS AND THEORETICAL LINE INTENSITIES FOR TRANSITIONS IN S III

We present Maxwellian-averaged effective collision strengths for the electron-impact excitation of S III over a wide range of electron temperatures of astrophysical importance, log T(K) = 3.0-6.0. The calculation incorporates 53 fine-structure levels arising from the six lowest configurations, giving rise to 1378 individual lines, and is undertaken using the recently developed RMATRX II plus FINE95 suite of codes. A detailed comparison is made with a previous R-matrix calculation and significant differences are found for some transitions. The atomic data are subsequently incorporated into the modeling code CLOUDY to generate line intensities for a range of plasma parameters, with emphasis on allowed UV and EUV emission lines detected from the Io plasma torus. Electron density-sensitive line ratios are calculated with the present atomic data and compared with those from CHIANTI v7.1, as well as with Io plasma torus spectra obtained by FUSE and EUVE. The present line intensities are found to agree well with the observational results and provide a noticeable improvement upon the values predicted by CHIANTI.

Unique solar flare of September 22, 2011: The suction effect

The specific features in the development of an X1 solar flare, which occurred on September 22, 2011, and was registered with the Atmospheric Imaging Assembly (AIA) device onboard the Solar Dynamics Observatory (SDO) in the UV line (λ = 304 A, He II), are analyzed. During the flare, which lasted about 12 h, cold plasma was sucked up with an increasing velocity from a very distant region into the low-lying hot region of flare energy release along a flat helical trajectory. This phenomenon fundamentally differs from a surge ejection, when matter previously ejected from the flare region returns to the flare hot zone under the action of gravity. Suction of cold plasma “from outside” into the hot flare region is interpreted in the scope of the rope flare mechanism, according to which an extremely inhomogeneous plasma density distribution in the cross-section originates in an emerging magnetic rope. In the region with a sharply decreased density (which is the suction region), the drift velocity in the current chanel can reach the ion thermal velocity, which inevitably results in the excitation of plasma turbulence and anomalous resistance, i.e., in the development of a flare.

A photoionization method for estimating BLR “size” in quasars

We describe an alternate way to estimate Broad Line Region (BLR) radii for type-1 AGN based on determination of physical conditions in the BLR under the assumption that the line emitting gas is photoionized by a central continuum source. We derive “diagnostic” intensity ratios involving UV lines Aliiiλ1860, Siiii]λ1892 and Civλ1549 which enable us to compute the ionizing photon flux, and hence BLR radius from the ionization parameter definition. We compare our estimates of BLR radii with values independently obtained from reverberation monitoring of Hβ and, in a few cases, of C ivλ1549. We analyze the interpretation of the photoionization estimates in the 4D eigenvector 1 context, and discuss in some detail the case of 3C 390.3. For this object we are able to provide not only the ionizing photon flux, but also an estimate of density and ionization parameter from the measured diagnostic ratios. We also compare black hole masses obtained from this method with values derived from widely-applied correlations between mass, line broadening and luminosity. Good agreement is found for both radius and black hole mass comparisons.

Ultraviolet diagnostic of porosity-free mass-loss estimates in B stars

We seek to establish evidence in UV P Cygni line profiles that the signs of wind clumping and porosity vary with velocity. We aim to demonstrate empirically that while at most wind velocities optically thick clumps cover only a fraction of the stellar surface, close to the terminal velocity where narrow absorption components (NACs) appear in UV lines the covering factor is approximately unity. SEI line-synthesis models are used to determine the radial optical depths of blue and red components of the SiIV 1400 resonance line doublet in a sample of 12 B0 to B4 supergiants. We focus on stars with well developed NACs and relatively low terminal velocity so that the SiIV doublet components can be treated as radiatively decoupled and formed independently. For all 12 stars the mean optical depth ratio of the blue to red components is closer to ~ 2 (i.e. the ratio of oscillator strengths) in the NACs than at intermediate and lower velocities. The product of mass-loss rate and Si^3+ ion fraction calculated from the NAC optical depths is a factor of ~ 2 to 9 higher compared to mass-loss values sampled at ~ 0.4 to 0.6 of the terminal velocity. Since the wind effectively becomes `smooth' at the high NAC velocities and the column density is uniformly distributed over the stellar disk, the optical depths of the NACs are not seriously affected by porosity and this feature thus provides the most reliable measurement of mass-loss rate in the UV lines. Applications of this result to the weak-wind problem of late O-dwarf stars and the "PV mass loss discordance" in early O supergiants are discussed.

Quantum Stark broadening of Ar XV lines. Strong collision and quadrupolar potential contributions

We present in this paper electron impact broadening for six Ar XV lines using our quantum mechanical formalism and the semiclassical perturbation one. Additionally, our calculations of the corresponding atomic structure data (energy levels and oscillator strengths) and collision strengths are given as well. The lines considered here are divided into two sets: a first set of four lines involving the ground level: 1s22s21S0– 1s22snp 1P1o where 2⩽n⩽5 and a second set of two lines involving excited levels: 1s22s2p 1P1o–1s22s3s 1S0 and 1s22s2p 3P0o–1s22s3s 3S1. An extensive comparison between the quantum and the semiclassical results was performed in order to analyze the reason for differences between quantum and semiclassical results up to the factor of two. It has been shown that the difference between the two results may be due to the evaluation of strong collision contributions by the semiclassical formalism. Except few semiclassical results, the present results are the first to be published. After the recent discovery of the far UV lines of Ar VII in the spectra of very hot central stars of planetary nebulae and white dwarfs, the present -and may be further- results can be used also for the corresponding future spectral analysis.

THE LOCATION OF NON-THERMAL VELOCITY IN THE EARLY PHASES OF LARGE FLARES—REVEALING PRE-ERUPTION FLUX ROPES

Non-thermal velocity measurements of the solar atmosphere, particularly from UV and X-ray emission lines have demonstrated over the decades that this parameter is important in understanding the triggering of solar flares. Enhancements have often been observed before intensity enhancements are seen. However, until the launch of Hinode, it has been difficult to determine the spatial location of the enhancements to better understand the source region. The Hinode EUV Imaging Spectrometer has the spectral and spatial resolution to allow us to probe the early stages of flares in detail. We analyze four events, all of which are GOES M- or X-classification flares, and all are located toward the limb for ease of flare geometry interpretation. Three of the flares were eruptive and one was confined. In all events, pre-flare enhancement in non-thermal velocity at the base of the active region and its surroundings has been found. These enhancements seem to be consistent with the footpoints of the dimming regions, and hence may be highlighting the activation of a coronal flux rope for the three eruptive events. In addition, pre-flare enhancements in non-thermal velocity were found above the looptops for the three eruptive events.

Discovery of the magnetic field in the pulsating B starβCephei

Although the star itself is not He enriched, the periodicity and the variability in the UV wind lines of the pulsating B1 IV star beta Cep are similar to what is observed in magnetic He-peculiar B stars, suggesting that beta Cep is magnetic. We searched for a magnetic field using spectropolarimetry. From UV spectroscopy, we analysed the wind variability and investigated the correlation with the magnetic data. Using 130 time-resolved circular polarisation spectra, obtained with the MuSiCoS spectropolarimeter at the 2m TBL from 1998 until 2005, we applied the least-squares deconvolution method on the Stokes V spectra and derived the longitudinal component of the integrated magnetic field over the visible hemisphere of the star. We performed a period analysis on the magnetic data and on EW measurements of UV wind lines obtained over 17 years. We also analysed the short- and long-term radial velocity variations, which are due to the pulsations and the 90-year binary motion. beta Cep hosts a sinusoidally varying magnetic field with an amplitude 97(4) G and an average value -6(3) G. From the UV wind line variability, we derive a period of 12.00075(11) days, which is the rotation period of the star, and is compatible with the observed magnetic modulation. Phases of maximum and minimum field match those of maximum emission in the UV wind lines, strongly supporting an oblique magnetic-rotator model. We discuss the magnetic behaviour as a function of pulsation behaviour and UV line variability. This paper presents the analysis of the first confirmed detection of a dipolar magnetic field in an upper main-sequence pulsating star. Maximum wind absorption originates in the magnetic equatorial plane. Maximum emission occurs when the magnetic north pole points to the Earth. Radial velocities agree with the ~90-y orbit around its Be-star binary companion.

Structural characterization of SiO2/Zn2SiO4:Ce nanocomposite obtained by sol gel method

Ce-doped ZnO nanopowder and ZnO:Ce/silica nanocomposite were synthesized by sol–gel process under supercritical drying (temperature and pressure) of ethanol. Annealing at 1200°C under atmospheric pressure has been achieved for the prepared ZnO:Ce/silica nanocomposite. X-ray diffraction (XRD) showed good crystallinity and a ZnO hexagonal wurtzite structure of the as-prepared powder. The average crystallite size is of the order of 78nm. Crystallites agglomerate to form spheres, hexagons and/or hexagons inserted in tori. The introduction of ZnO:Ce in silica leads to the formation of zinc silicate even before annealing. The heat treatment reduces the intensity of the diffraction peaks and enhanced the formation of this new phase. Photoluminescence (PL) spectra showed that the introduction of ZnO:Ce in silica before annealing reduces the UV lines and red shifts the entire emission. After annealing the PL intensity of the nanocomposite is significantly reduced.

The spectroscopic evolution of theγ-ray emitting classical nova Nova Mon 2012

Nova Mon 2012 was the first classical nova to be detected as a high energy $\gamma$-ray transient, by Fermi-LAT, before its optical discovery. We study a time sequence of high resolution optical echelle spectra (Nordic Optical Telescope) and contemporaneous NOT, STIS UV, and CHIRON echelle spectra (Nov 20/21/22). We use [O III] and H$\beta$ line fluxs to constrain the properties of the ejecta. We derive the structure from the optical and UV line profiles and compare our measured line fluxes for with predictions using Cloudy with abundances from other ONe novae. Mon 2012 is confirmed as an ONe nova. We find E(B-V)=0.85$\pm$0.05 and hydrogen column density $\approx 5\times 10^{21}$ cm$^{-2}$. The corrected continuum luminosity is nearly the same in the entire observed energy range as V1974 Cyg, V382 Mon, and Nova LMC 2000 at the same epoch after outburst. The distance, about 3.6 kpc, is quite similar to V1974 Cyg. The line profiles can be modeled using an axisymmetric bipolar geometry for the ejecta with various inclinations of the axis to the line of sight, 60 \le i \le 80 degrees, an opening angle of \approx$70 deg, inner radius $\Delta R/R(t)\approx 0.4$ for permitted lines and less filled for forbidden lines. The filling factor $f\approx 0.1-0.3$ implying M(ejecta) $\leq 6\times 10^{-5}$M$_\odot$. The ONe novae appear to comprise a single physical class with bipolar high mass ejecta, similarly enhanced abundances, and a common spectroscopic evolution within a narrow range of luminosities. The detected $\gamma$-ray emission may be a generic phenomenon, common to all ONe novae, possibly to all classical novae, and connected with acceleration and emission processes within the ejecta (abstract severely truncated).

Phase-resolved ultraviolet spectroscopy of the magnetic Of?p star HD 191612

We present for the first time phase-resolved UV spectroscopy of an Of?p star, namely, HD 191612. The observations were acquired with the Space Telescope Imaging Spectrograph (STIS) on-board the Hubble Space Telescope (HST). We report the variability observed in the main photospheric and wind features and compare the results with previous findings for the Of?p star HD 108. We show that UV line strengths, H(alpha), and longitudinal magnetic field, vary coherently according to the rotational period (P = 537.6d), providing additional support for the magnetic oblique rotator scenario. The stellar and wind parameters of HD 191612 are obtained based on NLTE expanding atmosphere models. The peculiar wind line profile variations revealed by the new STIS data - not reproduced by 1D atmosphere models - are addressed through non-spherical MHD simulations coupled with radiative transfer. The basic aspects of the UV variability observed are explained and the structure of the dynamical magnetosphere of HD 191612 is discussed.

Soft X-ray and ultraviolet metal-line emission from the gas around galaxies

(Abridged) A large fraction of the gas in galactic haloes has temperatures between 10^4.5 and 10^7 K. At these temperatures, cooling is dominated by metal-line emission if the metallicity Z>~0.1 Zsun. We explore the detectability of several lines using large cosmological, hydrodynamical simulations. We stack surface brightness maps centred on galaxies to calculate the expected mean surface brightness profiles for different halo masses. Assuming a detection limit of 10^-1 photon s^-1 cm^-2 sr^-1, proposed X-ray telescopes can detect O VIII emission from z=0.125 out to 80% of the virial radius (Rvir) of groups and clusters and out to 0.4Rvir for haloes with masses Mhalo=10^12-13 Msun. Emission lines from C VI, N VII, O VII, and Ne X can be detected out to smaller radii, 0.1-0.5Rvir. With a detection limit of 10^-20 erg s^-1 cm^-2 arcsec^-2, future UV telescopes can detect C III emission out to 0.2-0.6Rvir at z=0.25. C IV, O VI, Si III, and Si IV can be seen out to 0.1-0.2Rvir for Mhalo>10^12 Msun. Optical HI H-alpha emission is comparable in strength to C III emission. At z=3 it may be possible to observe C III out to 0.2-0.3Rvir and other rest-frame UV lines out to ~0.1Rvir for Mhalo>10^11 Msun with upcoming optical instruments. Metal-line emission is typically biased towards high density and metallicity and towards the temperature at which the emissivity curve of the corresponding metal line peaks. The bias is similar for the different soft X-ray lines considered, whereas it varies strongly between different UV lines. Active galactic nucleus (AGN) feedback can change the inner surface brightness profiles significantly, but it generally does not change the radius out to which the emission can be observed. Metal-line emission is a promising probe of the warm and hot, enriched gas around galaxies and provides a unique window into the interactions between galaxies and their gaseous haloes.

The ionized absorber and nuclear environment of IRAS 13349+2438: multi-wavelength insights from coordinated Chandra HETGS, HST STIS, HET and Spitzer IRS

We present results from a coordinated IR-to-X-ray spectral campaign of the QSO IRAS 13349+2438. Optical spectra reveal extreme Eigenvector-1 characteristics, but the H-beta line width argues against a NLS1 classification; we refine z=0.10853 based on [O III]. We estimate a BH mass=10^9 Msun using 2 independent methods (H-beta line width & SED fits). Blue-shifted absorption (-950km/s & -75km/s) is seen for the 1st time in STIS UV spectra from Ly-alpha, NV, & CIV. The higher velocity UV lines are coincident with the lower-ionisation (xi~1.6) X-ray warm absorber lines. A dusty multiple ionization absorber blueshifted by 700-900km/s is required to fit the X-ray data. Theoretical models comparing different ionising SEDs reveal that a UV-inclusive (i.e., the accretion disc) ionising continuum strongly impacts conclusions for the thermodynamic stability of the warm absorber. Specific to IRAS13349, an Xray-UV ionising SED favors a continuous distribution of ionisation states in a smooth flow (this paper), versus discrete clouds in pressure equilibrium (work by others where UV is omitted). Direct dust detections are seen in both the IR: PAH emission at (7.7 & 11.3)micron which may also be blended with forsterite, and (10 & 18)micron silicate emission, and X-rays: iron dust with a dust-to-gas ratio > 90%. We develop a geometrical model whereby the QSO nuclear region is viewed through the upper atmosphere of an obscuring torus. This sight line is obscured by dust that blocks a direct view of the UV/optical emission region but is largely transparent in X-rays since the gas is ionised. In our model, 20% of the intrinsic UV/optical continuum is scattered into our sight line by the far wall of an obscuring torus. An additional 2.4% of the direct light, which likely dominates the UV emission, is Thomson-scattered into our line-of-sight by another off-plane component of highly ionized gas.

Mg II ABSORPTION AT 2 <z< 6 WITH MAGELLAN/FIRE. II. A LONGITUDINAL STUDY OF H I, METALS, AND IONIZATION IN GALACTIC HALOS

We present a detailed study of HI and metals for 110 MgII absorption systems discovered at 1.98 <= z <= 5.33 in the infrared spectra of high redshift QSOs. Using new measurements of rest-frame UV lines from optical spectra of the same targets, we compare the high redshift sample with carefully constructed low redshift control samples from the literature to study evolutionary trends from z=0 --> 5.33 (>12 Gyr). We observe a significant strengthening in the characteristic N(HI) for fixed MgII equivalent width as one moves toward higher redshift. Indeed at our sample's mean zbar=3.402, all MgII systems are either damped Ly-alpha absorbers or sub-DLAs, with 40.7% of systems exceeding the DLA threshold (compared to 16.7% at zbar=0.927). We set lower limits on the metallicity of the MgII systems where we can measure HI; these results are consistent with the full DLA population. The classical MgII systems (W(2796)=0.3-1.0 Ang), which preferentially associate with sub-DLAs, are quite metal rich at ~0.1 Solar. We applied quantitative classification metrics to our absorbers to compare with low redshift populations, finding that weak systems are similar to classic MgII absorbers at low redshift. The strong systems either have very large MgII and FeII velocity spreads implying non-virialized dynamics, or are more quiescent DLAs. There is tentative evidence that the kinetically complex systems evolve in similar fashion to the global star formation rate. We speculate that if weaker MgII systems represent accreting gas as suggested by recent studies of galaxy-absorber inclinations, then their high metal abundance suggests re-accretion of recently ejected material rather than first-time infall from the metal-poor IGM, even at early times.

LOOKING DEEP INTO THE CAT'S EYE: STRUCTURE AND ROTATION IN THE FAST WIND OF THE PN CENTRAL STAR OF NGC 6543

We present HST/STIS time-series spectroscopy of the central star of the "Cat's Eye" planetary nebula NGC 6543. Intensive monitoring of the UV lines over a 5.8 hour period reveals well defined details of large-scale structure in the fast wind, which are exploited to provide new constraints on the rotation rate of the central star. We derive characteristics of the line profile variability that support a physical origin due to co-rotating interaction regions (CIRs) that are rooted at the stellar surface. The recurrence time of the observed spectral signatures of the CIRs is used to estimate the rotation period of the central star and, adopting a radius between 0.3 and 0.6 \Rsun constrains the rotational velocity to the range 54 \leq v_{rot} \leq 108 \kms. The implications of these results for single star evolution are discussed based on models calculated here for low-mass stars. Our models predict a sub-surface convective layer in NGC 6543 which we argue to be causally connected to the occurrence of structure in the fast wind.

THE HANLE EFFECT OF Lyα IN A MAGNETOHYDRODYNAMIC MODEL OF THE SOLAR TRANSITION REGION

In order to understand the heating of the solar corona it is crucial to obtain empirical information on the magnetic field in its lower boundary (the transition region). To this end, we need to measure and model the linear polarization produced by scattering processes in strong UV lines, such as the hydrogen Ly$\alpha$ line. The interpretation of the observed Stokes profiles will require taking into account that the outer solar atmosphere is highly structured and dynamic, and that the height of the transition region may well vary from one place in the atmosphere to another. Here we report on the Ly$\alpha$ scattering polarization signals we have calculated in a realistic model of an enhanced network region, resulting from a state-of-the-art radiation MHD simulation. This model is characterized by spatially complex variations of the physical quantities at transition region heights. The results of our investigation lead us to emphasize that scattering processes in the upper solar chromosphere should indeed produce measurable linear polarization in Ly$\alpha$. More importantly, we show that via the Hanle effect the model's magnetic field produces significant changes in the emergent $Q/I$ and $U/I$ profiles. Therefore, we argue that by measuring the polarization signals produced by scattering processes and the Hanle effect in Ly$\alpha$ and contrasting them with those computed in increasingly realistic atmospheric models, we should be able to decipher the magnetic, thermal and dynamic structure of the upper chromosphere and transition region of the Sun.

Less contribution of nonradiative recombination in ZnO nails compared with rods

Well aligned ZnO nails with small heads and rods arrays have been grown on indium tin oxides (ITO) substrates by a simple hydrothermal method without any metal catalyst or additives. The optical properties of the as-grown ZnO microstructures were investigated by room-temperature and temperature-dependent photoluminescence spectra. From the PL spectra measured in the range of 80–300K, the origins of near-band-gap UV lines have been identified in terms of bound exciton complexes and the phonon replicas. We also estimated that the activation energy of the temperature quenching for ZnO nails is higher than that of rods, indicating less nonradiative recombination contributes to the emission process in ZnO nails, which was further testified by the time-resolved PL results. Thus, the relative emission intensity ratio between UV and deep level emission in room-temperature PL spectra for nails is 2.3-times higher than that of rods.

Discovery of a magnetic field in the early B-type starσLupi

Magnetic early B-type stars are rare. To identify them, we use the strongest indirect indicator of a magnetic field in B stars, which is periodic variability of UV stellar wind lines occurring symmetric about the approximate rest wavelength. Probable magnetic candidates are targets for follow-up spectropolarimetry to search for a magnetic field. From the UV wind line variability the B1/B2V star sigma Lupi emerged as a new magnetic candidate star. AAT spectropolarimetric measurements with SEMPOL were obtained. The longitudinal component of the magnetic field integrated over the visible surface of the star was determined with the Least-Squares Deconvolution method. The UV line variations of sigma Lupi are similar to what is known in magnetic B stars, but no periodicity could be determined. We detected a varying longitudinal magnetic field with amplitude of about 100 G with error bars of typically 20 G, which supports an oblique magnetic-rotator configuration. The EW variations of the UV lines, the magnetic and the optical-line variations are consistent with the photometric period of 3.02 d, which we identify with the rotation period of the star. Additional observations with ESPaDOnS attached to the CFHT confirmed this discovery, and allowed the determination of a precise magnetic period. Analysis revealed that sigma Lupi is a He-strong star, with an enhanced N abundance and an underabundance of C, and has a chemically spotted surface. Like in other magnetic B stars the UV wind emission appears to originate close to the magnetic equatorial plane, with maximum emission when a magnetic pole points towards the Earth. The 3.01972(43) d magnetic rotation period is consistent with the photometric period, with maximum light corresponding to maximum magnetic field.

On the formation of C iii 4647-50-51 and C iii 5696 in O star atmospheres

We investigate the formation of CIII 4647-51-50 and CIII 5696 in the atmosphere of O stars to see if they can be reliably used for abundance determinations. We use atmosphere models computed with the code CMFGEN. The key physical ingredients explaining the formation of the CIII lines are extracted from comparisons of models with different stellar parameters and through examining rates controlling the level populations. The strength of CIII 5696 critically depends on UV CIII lines at 386, 574 and 884 A. These lines control the CIII 5696 upper and lower level population. CIII 884 plays a key role in late O stars where it drains the lower level of CIII 5696. CIII 386 and CIII 574 are more important at early spectral types. The overlap of these UV lines with FeIV 386.262, FeIV 574.232 and SV 884.531 influences the radiative transfer at 386, 574 and 884 A, and consequently affects the strength of CIII 5696. CIII 4650 is mainly controlled by the CIII 538 line which acts as a drain on its lower level. FeIV 538.057 interacts with CIII 538 and has an impact on the CIII 4650 profile. Low temperature dielectronic recombinations have a negligible effect on the line profiles. Given our current understanding of the stellar and wind properties of O stars, and in view of the present results, the determination of accurate carbon abundances from CIII 4647-51-50 and CIII 5696 is an extremely challenging task. Uncertainties lower than a factor of two on C/H determinations based only on these two sets of lines should be regarder as highly doubtful. Our results provide a possible explanation of the variability of CIII 4650 in Of?p stars.

A combined optical and X-ray study of unobscured type 1 active galactic nuclei - III. Broad-band SED properties

In this third paper in a series of three, we present a detailed study of the AGN broadband SED based on a nearby unobscured Type 1 AGN sample. We perform a systematic cross-correlation study of the following key parameters: $\Gamma_{2-10keV}$, $L_{2-10keV}$, $L_{bol}$, $L_{bol}/L_{Edd}$, $\kappa_{2-10keV}$, $\kappa_{5100A}$, FWHM$_{H\beta}$, M$_{BH}$, $\alpha_{ox}$, $\alpha_{X}$ and $\alpha_{UV}$, and identify various strong correlations among these parameters. The principal component analysis (PCA) is performed on the correlation matrix of the above parameters, which shows that the three physical parameters, i.e. black hole mass, mass accretion rate and Eddington ratio, drive the majority of the correlations. This is consistent with PCA results found from previous optical spectral studies. We produce various mean SEDs classified by each of the key parameters. Most parameters, except L$_{bol}$, show similar systematic changes in the mean SEDs such that the temperature at which the disc peaks is correlated with the ratio of power in the disc versus the Comptonised components and the hard X-ray spectral index. This underlying change in SED shape shows that AGN do exhibit intrinsically different spectral states. This is superficially similar to the SED differences in BHB seen as $\lambda_{Edd}$ increases, but the analogy does not hold in detail. Only objects with the highest $\lambda_{Edd}$ appear to correspond to a BHB spectral state (the disc dominated high/soft state). The AGN with typical mass accretion rates have spectra which do not match well with any state observed in BHB. We speculate that this could be due to the presence of a powerful UV line driven disc wind, which complicates simple mass scaling between stellar and supermassive black holes.

Accretion and outflow of gas in Markarian 509

AbstractA major uncertainty in models for photoionised outflows in AGN is the distance of the gas to the central black hole. We present the results of a massive multiwavelength monitoring campaign on the bright Seyfert 1 galaxy Mrk 509 to constrain the location of the outflow components dominating the soft X-ray band. Mrk 509 was monitored by XMM-Newton, Integral, Chandra, HST/COS and Swift in 2009. We have studied the response of the photoionised gas to the changes in the ionising flux produced by the central regions. We were able to put tight constraints on the variability of the absorbers from day to year time scales. This allowed us to develop a model for the time-dependent photoionisation in this source. We find that the more highly ionised gas producing most X-ray line opacity is at least 5 pc away from the core; upper limits to the distance of various absorbing components range between 20 pc up to a few kpc. The more lowly ionised gas producing most UV line opacity is at least 100 pc away from the nucleus. These results point to an origin of the dominant, slow (v&lt;1000 km s−1) outflow components in the NLR or torus-region of Mrk 509. We find that while the kinetic luminosity of the outflow is small, the mass carried away is likely larger than the 0.5 Solar mass per year accreting onto the black hole. We also determined the chemical composition of the outflow as well as valuable constraints on the different emission regions. We find for instance that the resolved component of the Fe-K line originates from a region 40–1000 gravitational radii from the black hole, and that the soft excess is produced by Comptonisation in a warm (0.2–1 keV), optically thick (τ~ 10–20) corona near the inner part of the disk.