Photoionization Modeling and the K Lines of Iron

Kallman, T. R.; Palmeri, P.; Bautista, M. A.; Mendoza, C.; Krolik, Julian H.

doi:10.1086/424039

Cited by 318 publications

(405 citation statements)

References 43 publications

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“…We find an emission line at 6.4 keV in HETGS and Epic-pn spectra, consistent with fluorescent emission from Fe i-Fe xv (Kallman et al 2004) with an ionisation parameter ξ ≤ 10, similar to the one associated with O vii. The broadening of the line at 6.4 keV is 18 ±3 eV as measured by the HETGS (see Table 2).…”

Section: The Neutral/partially Ionised Iron Linesupporting

confidence: 78%

X-ray spectroscopy of the ADC source X1822-371 withChandraandXMM-Newton

Iaria

Salvo

D’Aí

et al. 2012

A&A

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Context. The eclipsing low-mass X-ray binary X1822-371 is the prototype of the accretion disc corona (ADC) sources. Its inclination angle ( 82.5 • ) is high enough that flux from the neutron star is blocked by the edge-on accretion disc. Because the neutron star's direct emission is hidden, its ADC emission is visible. The physical properties of the ADC in X1822-371 have been widely studied, but are still debated in literature. In light of the recent literature and of the results reported in this work we show that the ADC is optically thin. Aims. We analyse two Chandra observations and one XMM-Newton observation to study the discrete features in this source and their variation as a function of the orbital phase, deriving constraints on the temperature, density, and location of the plasma responsible for emission lines. Methods. The HETGS and XMM/Epic-pn observed X1822-371 for 140 and 50 ks, respectively. We extracted an averaged spectrum and five spectra from five selected orbital-phase intervals that are 0.04-0.25, 0.25-0.50, 0.50-0.75, 0.75-0.95, and, finally, 0.95-1.04; the orbital phase zero corresponds to the eclipse time. All spectra cover the energy band between 0.35 and 12 keV. Results. We confirm the presence of local neutral matter that partially covers the X-ray emitting region; the equivalent hydrogen column is 5 × 10 22 cm −2 and the covered fraction is about 60-65%. We identify several emission lines of He-like and H-like ions, and a prominent fluorescence iron line associated with a blending of Fe i-Fe xv resonant transitions. The transitions of He-like ions show that the intercombination dominates over the forbidden and resonance lines. The line fluxes are the highest during the orbital phases between 0.04 and 0.75. Conclusions. We discuss the presence of an extended, optically thin corona with optical depth of about 0.01 that scatters the X-ray photons from the innermost region into the line of sight. The photoionised plasma producing the O viii, Ne ix, Ne x, Mg xi, Mg xii, Si xiii, and Si xiv lines is placed in the bulge at the outer radius of the disc distant from the central source of 6 × 10 10 cm. The O vii and the fluorescence iron line are probably produced in the photoionised surface of the disc at inner radii. Finally, we suggest that the observed local neutral matter is the matter transferred by the companion star that was expelled from the system by the X-ray radiation pressure, which in turn originated in the accretion process onto the neutron star.

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Section: The Neutral/partially Ionised Iron Linesupporting

confidence: 78%

X-ray spectroscopy of the ADC source X1822-371 withChandraandXMM-Newton

Iaria

Salvo

D’Aí

et al. 2012

A&A

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“…After having characterized the X-ray data of PID352 using a "phenomenological" model, we modeled the XMM-Newton data using grids from the photoionization code xstar (Bautista & Kallman 2001;Kallman et al 2004) to derive the physical parameters for the X-ray outflowing gas (primarily its location and the mass outflow rate), which are clearly affected by large uncertainties given the limited significance of the absorption line.…”

Section: Radio Datamentioning

confidence: 99%

The XMM deep survey in the CDF-S

Vignali

Iwasawa

Comastri

et al. 2015

A&A

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In active galactic nuclei (AGN)-galaxy co-evolution models, AGN winds and outflows are often invoked to explain why super-massive black holes and galaxies stop growing efficiently at a certain phase of their lives. They are commonly referred to as the leading actors of feedback processes. Evidence of ultra-fast (v > ∼ 0.05c) outflows in the innermost regions of AGN has been collected in the past decade by sensitive X-ray observations for sizable samples of AGN, mostly at low redshift. Here we present ultra-deep XMM-Newton and Chandra spectral data of an obscured (N H ≈ 2 × 10 23 cm −2 ), intrinsically luminous (L 2−10 keV ≈ 4 × 10 44 erg s −1 ) quasar (named PID352) at z ≈ 1.6 (derived from the X-ray spectral analysis) in the Chandra Deep Field-South. The source is characterized by an iron emission and absorption line complex at observed energies of E ≈ 2−3 keV. While the emission line is interpreted as being due to neutral iron (consistent with the presence of cold absorption), the absorption feature is due to highly ionized iron transitions (FeXXV, FeXXVI) with an outflowing velocity of 0.14 +0.02 −0.06 c, as derived from photoionization models. The mass outflow rate -∼2 M yr −1 -is similar to the source accretion rate, and the derived mechanical energy rate is ∼9.5 × 10 44 erg s −1 , corresponding to 9% of the source bolometric luminosity. PID352 represents one of the few cases where indications of X-ray outflowing gas have been observed at high redshift thus far. This wind is powerful enough to provide feedback on the host galaxy.

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“…To investigate the possibility of such a shift we froze the line energies of all measured elements to the values of their respective neutral line energy, with values taken from Palmeri et al (2008b) for S, Ar, and Ca, Kaastra & Mewe (1993) for Cr, Kallman et al (2004) for Fe, and Palmeri et al (2008a) for Ni. We then applied a gainshift kernel, shifting the model counts spectrum energy grid according to E new (c) = E old (c)/gainshift.…”

Section: Time Resolved Spectramentioning

confidence: 99%

Study of the many fluorescent lines and the absorption variability in GX 301−2 withXMM-Newton

Fürst¹,

Suchy

Kreykenbohm³

et al. 2011

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We present an in-depth study of the high mass X-ray binary (HMXB) GX 301−2 during its pre-periastron flare using data from the XMM-Newton satellite. The energy spectrum shows a power law continuum absorbed by a large equivalent hydrogen column on the order of 10 24 cm −2 and a prominent Fe Kα fluorescent emission line. Besides the Fe Kα line, evidence for Fe Kβ, Ni Kα, Ni Kβ, S Kα, Ar Kα, Ca Kα, and Cr Kα fluorescent lines is found. The observed line strengths are consistent with fluorescence in a cold absorber. This is the first time that Cr Kα is seen in emission in the X-ray spectrum of a HMXB. In addition to the modulation by the strong pulse period of ∼685 s the source is highly variable and shows different states of activity. We perform time-resolved as well as pulse-to-pulse resolved spectroscopy to investigate differences between these states of activity. We find that fluorescent line fluxes are strongly variable and generally follow the overall flux. The N H value is variable by a factor of 2, but not correlated to continuum normalization. We find an interval of low flux in the light curve in which the pulsations cease almost completely, without any indication of an increasing absorption column. We investigate this dip in detail and argue that it is most likely that during the dip the accretion ceased and the afterglow of the fluorescent iron accounted for the main portion of the X-ray flux. A similar dip was found earlier in RXTE data, and we compare our findings to these results.

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Photoionization Modeling and the K Lines of Iron

Cited by 318 publications

References 43 publications

X-ray spectroscopy of the ADC source X1822-371 withChandraandXMM-Newton

X-ray spectroscopy of the ADC source X1822-371 withChandraandXMM-Newton

The XMM deep survey in the CDF-S

Study of the many fluorescent lines and the absorption variability in GX 301−2 withXMM-Newton

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