Context. Our consortium performed an extensive multi-wavelength campaign of the nearby Seyfert 1 galaxy NGC 5548 in 2013-14. The source appeared unusually heavily absorbed in the soft X-rays, and signatures of outflowing absorption were also present in the UV. He-like triplets of neon, oxygen and nitrogen, and radiative recombination continuum (RRC) features were found to dominate the soft X-ray spectrum due to the low continuum flux. Aims. Here we focus on characterising these narrow emission features using data obtained from the XMM-Newton RGS (770 ks stacked spectrum). Methods. We use SPEX for our initial analysis of these features. Self-consistent photoionisation models from Cloudy are then compared with the data to characterise the physical conditions of the emitting region. Results. Outflow velocity discrepancies within the O VII triplet lines can be explained if the X-ray narrow-line region (NLR) in NGC 5548 is absorbed by at least one of the six warm absorber components found by previous analyses. The RRCs allow us to directly calculate a temperature of the emitting gas of a few eV ($\sim10^{4}$ K), favouring photoionised conditions. We fit the data with a Cloudy model of log $ξ= 1.45 \pm 0.05$ erg cm s$^{-1}$, log $N_H = 22.9 \pm 0.4$ cm$^{-2}$ and log v$_{turb} = 2.25 \pm 0.5$ km s$^{-1}$ for the emitting gas; this is the first time the X-ray NLR gas in this source has been modelled so comprehensively. This allows us to estimate the distance from the central source to the illuminated face of the emitting clouds as $13.9 \pm 0.6$ pc, consistent with previous work.

Outflow

10.1051/0004-6361/201526742

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Anatomy of the AGN in NGC 5548 IX. Photoionized emission features in the soft X-ray spectra

Junjie Mao J. S. Kaastra M. Mehdipour Liyi Gu E. Costantini

The X-ray narrow emission line region (NELR) of the archetypal Seyfert 1 galaxy NGC\,5548 has been interpreted as a single-phase photoionized plasma that is absorbed by some of the warm absorber components. This scenario requires those overlaying warm absorber components to have larger distance (to the central engine) than the X-ray NELR, which is not fully consistent with the distance estimates found in the literature. Therefore, we reanalyze the high-resolution spectra obtained in 2013--2014 with the Reflection Grating Spectrometer (RGS) aboard \textit{XMM}-Newton to provide an alternative interpretation of the X-ray narrow emission features. We find that the X-ray narrow emission features in NGC\,5548 can be described by a two-phase photoionized plasma with different ionization parameters ($\log \xi=1.3$ and $0.1$) and kinematics ($v_{\rm out}=-50$ and $-400~{\rm km~s^{-1}}$), and no further absorption by the warm absorber components. The X-ray and optical NELR might be the same multi-phase photoionized plasma. Both X-ray and optical NELR have comparable distances, asymmetric line profiles, and the underlying photoionized plasma is turbulent and compact in size. The X-ray NELR is not the counterpart of the UV/X-ray absorber outside the line of sight because their distances and kinematics are not consistent. In addition, X-ray broad emission features that we find in the spectrum can be accounted for by a third photoionized emission component. The RGS spectrum obtained in 2016 is analyzed as well, where the luminosity of most prominent emission lines (the \ion{O}{vii} forbidden line and \ion{O}{viii} Ly$\alpha$ line) are the same (at a 1 $\sigma$ confidence level) as in 2013--2014.

Line (geometry)

Line-of-sight

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EXACT: A study of the Earth's aurora using a Cubesat

European Planetary Science Congress 2010 (2010)

G. Branduardi‐Raymont D. O. Kataria Dean Walton A. N. Fazakerley A. J. Coates

Despite the relationship between solar wind conditions and the Earth’s auroral emissions, no systematic attempt has yet been made to correlate the two with in-situ coordinated particle and radiation measurements, and X-ray measurements in particular. We have studied how to do this with a dedicated, low-cost, nano-satellite, a Cubesat, carrying miniaturised and yet very effective instrumentation, which will open the way to a better targeted and global approach to planetary exploration. We are especially keen to observe the Xray aurora, which is associated with the most energetic particles and has not been explored in detail yet, and to correlate its strength and variability with simultaneous particle and magnetic field measurements. This presentation will describe the aims of the mission and the strategy to carry it out.

CubeSat

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Shining light on obscured AGN outflows

HST Proposal (2015)

J. S. Kaastra Nahum Arav Ehud Behar S. Bianchi G. Branduardi‐Raymont

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Multi-wavelength study of the Seyfert 1 galaxy NGC 3783 with XMM-Newton

Astronomy and Astrophysics (2002)

A. J. Blustin G. Branduardi‐Raymont E. Behar J. S. Kaastra S. M. Kahn

We present the analysis of multi-wavelength XMM-Newton data from the Seyfert galaxy NGC 3783, including UV imaging, X-ray and UV lightcurves, the 0.2-10 keV X-ray continuum, the iron Kα emission line, and high-resolution spectroscopy and modelling of the soft X-ray warm absorber. The 0.2-10 keV spectral continuum can be well reproduced by a power-law at higher energies; we detect a prominent Fe Kα emission line, with both broad and narrow components, and a weaker emission line at 6.9 keV which is probably a combination of Fe Kβ and . We interpret the significant deficit of counts in the soft X-ray region as being due to absorption by ionised gas in the line of sight. This is demonstrated by the large number of narrow absorption lines in the RGS spectrum from iron, oxygen, nitrogen, carbon, neon, argon, magnesium, silicon and sulphur. The wide range of iron states present in the spectrum enables us to deduce the ionisation structure of the absorbing medium. We find that our spectrum contains evidence of absorption by at least two phases of gas: a hotter phase containing plasma with a log ionisation parameter ξ (where ξ is in erg cm s) of 2.4 and greater, and a cooler phase with log ξ centred around 0.3. The gas in both phases is outflowing at speeds of around 800 km s. The main spectral signature of the cold phase is the Unresolved Transition Array (UTA) of M-shell iron, which is the deepest yet observed; its depth requires either that the abundance of iron, in the cold phase, is several times that of oxygen, with respect to solar abundances, or that the absorption lines associated with this phase are highly saturated. The cold phase is associated with ionisation states that would also absorb in the UV.

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Spectral resolution

10.1051/0004-6361:20020914

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X‐ray views of our solar system

Astronomische Nachrichten (2021)

G. Branduardi‐Raymont

Abstract The solar system comprises a relatively small number of X‐ray emitting objects, which are associated with a variety of physical emission processes: we can explore them with good spatial and temporal precision at relatively local distances, and in situ as well, unlike the rest of the Universe. Moreover, from the study of the solar system, we can gather insights into extra‐solar planets too. This article offers a review of our current knowledge of the X‐ray properties of bodies in our solar system, of the physical processes leading to X‐ray emissions, and of recent breakthrough discoveries brought about by space probes providing remote imaging as well as in situ measurements. In the long term, the next generation of Earth‐bound X‐ray observatories and the possibility of in situ X‐ray measurements, that is, by X‐ray telescopes onboard spacecraft visiting the planets, will underpin the next giant leap in discovery space.

10.1002/asna.20210101

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SMILE: a mission to image the solar wind-magnetosphere interaction

C. P. Escoubet G. Branduardi‐Raymont Chi Wang

The interaction between the solar wind and the Earth's magnetosphere, and the geospace dynamics that result, is one of the key questions in space plasma physics. In situ instruments on a fleet of solar wind and magnetospheric constellation missions now provide the most detailed observations of Sun-Earth connections over multiple scales, from the smallest of a few kilometres up to the largest of a few 10s of Earth radii. However, we are still unable to quantify the global effects of the drivers of such connections, including the conditions that prevail throughout geospace. This information is the key missing link for developing a complete understanding of how the Sun gives rise to and controls Earth's plasma environment and space weather. This is where SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) comes in.SMILE is a novel self-standing mission dedicated to observing the solar wind - magnetosphere coupling via simultaneous in situ solar wind/magnetosheath plasma and magnetic field measurements, soft X-ray imaging of the magnetosheath, magnetopause and polar cusps, and UV imaging of the northern hemisphere auroral oval. Remote sensing of the magnetosheath and cusps with soft X-ray imaging is made possible thanks to solar wind charge exchange (SWCX) X-ray emissions known to occur in the vicinity of the Earth's magnetosphere. SMILE is a joint mission between ESA and the Chinese Academy of Sciences (CAS) due for launch at the beginning of 2025. SMILE science objectives as well as the latest scientific and technical developments jointly undertaken by ESA and CAS and the international instrument teams will be presented.

Magnetosheath

Space physics

Space Weather

Polar wind

Magnetosphere of Jupiter

Magnetosphere of Saturn

10.5194/egusphere-egu23-12353

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The filter wheel and filters development for the X-IFU instruments on-board Athena

E. Bozzo Marco Barbera Ludovic Genolet S. Paltani M. Sordet

Athena is the large mission selected by ESA in 2013 to investigate the science theme “Hot and Energetic Universe” and presently scheduled for launch in 2028. One of the two instruments located at the focus of the 12 m-long Athena telescope is the X-ray Integral Field Unit (X-IFU). This is an array of TES microcalorimeters that will be operated at temperatures of 50 mK in order to perform high resolution spectroscopy with an energy resolution down to 2.5 eV at energies < 7 keV. In order to cope with the large dynamical range of X-ray fluxes spanned by the celestial objects Athena will be observing, the X-IFU will be equipped with a filter wheel. This will allow the user to fine tune the instrument set-up based on the nature of the target, thus optimizing the scientific outcomes of the observation. A few positions of the filter wheel will also be used to host a calibration source and to allow the measurement of the instrument intrinsic background.

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MHD simulations of magnetospheric response to a strong solar wind density pulse

Andrey Samsonov Jennifer Carter G. Branduardi‐Raymont S. Sembay

<p>On 16-17 June 2012, an interplanetary coronal mass ejection with an extremely high solar wind density (~100 cm<sup>-3</sup>) and mostly strong northward (or eastward) interplanetary magnetic field (IMF) interacted with the Earth&#8217;s magnetosphere. We have simulated this event using global MHD models. We study the magnetospheric response to two solar wind discontinuities. The first is characterized by a fast drop of the solar wind dynamic pressure resulting in rapid magnetospheric expansion. The second is a northward IMF turning which causes reconfiguration of the magnetospheric-ionospheric currents. We discuss variations of the magnetopause position and locations of the magnetopause reconnection in response to the solar wind variations. In the second part of our presentation, we present simulation results for the forthcoming SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) mission. SMILE is scheduled for launch in 2024. We produce two-dimensional images that derive from the MHD results of the expected X-ray emission as observed by the SMILE Soft X-ray Imager (SXI).&#160;We discuss how SMILE observations may help to study events like the one presented in this work.</p>

Magnetosheath

10.5194/egusphere-egu21-8329

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Identifying the variety of jovian X-ray auroral structures: tying the morphology of X-ray emissions to associated magnetospheric dynamics

Zenodo (CERN European Organization for Nuclear Research) (2023)

D. M. Weigt C. M. Jackman Diego Moral Pombo S. V. Badman Corentin Louis

The data used in Weigt et al., study "Identifying the variety of jovian X-ray auroral structures: tying the morphology of X-ray emissions to associated magnetospheric dynamics". The README.pdf explains what data is used to produce each Figure in the article with links to the Chandra archive and other data repositories. Pipeline to analyse data can be found here:

https://doi.org/10.5281/zenodo.7380282

Tying

10.5281/zenodo.8375369

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