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Graziella Branduardi-Raymont

Publications and source records attributed to Graziella Branduardi-Raymont.

At least 19 recordsLinked to original sources
arXiv2023

Revolutionary Solar System Science Enabled by the Line Emission Mapper X-ray Probe

The Line Emission Mapper's (LEM's) exquisite spectral resolution and effective area will open new research domains in Astrophysics, Planetary Science and Heliophysics. LEM will provide step-change capabilities for the fluorescence, solar wind charge exchange (SWCX) and auroral precipitation processes that dominate X-ray emissions in our Solar System. The observatory will enable novel X-ray measurements of historically inaccessible line species, thermal broadening, characteristic line ratios and Doppler shifts - a universally valuable new astrophysics diagnostic toolkit. These measurements will identify the underlying compositions, conditions and physical processes from km-scale ultra-cold comets to the MK solar wind in the heliopause at 120 AU. Here, we focus on the paradigm-shifts LEM will provide for understanding the nature of the interaction between a star and its planets, especially the fundamental processes that govern the transfer of mass and energy within our Solar System, and the distribution of elements throughout the heliosphere. In this White Paper we show how LEM will enable a treasure trove of new scientific contributions that directly address key questions from the National Academies' 2023-2032 Planetary Science and 2013-2022 Heliophysics Decadal Strategies. The topics we highlight include: 1. The richest global trace element maps of the Lunar Surface ever produced; insights that address Solar System and planetary formation, and provide invaluable context ahead of Artemis and the Lunar Gateway. 2. Global maps of our Heliosphere through Solar Wind Charge Exchange (SWCX) that trace the interstellar neutral distributions in interplanetary space and measure system-wide solar wind ion abundances and velocities; a key new understanding of our local astrosphere and a synergistic complement to NASA IMAP observations of heliospheric interactions...

astro-ph.IM↗
arXiv2023

Line Emission Mapper (LEM): Probing the physics of cosmic ecosystems

The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative new observing capabilities for every area of astrophysics, and to heliophysics and planetary physics as well. LEM's main goal is a comprehensive look at the physics of galaxy formation, including stellar and black-hole feedback and flows of baryonic matter into and out of galaxies. These processes are best studied in X-rays, and emission-line mapping is the pressing need in this area. LEM will use a large microcalorimeter array/IFU, covering a 30x30' field with 10" angular resolution, to map the soft X-ray line emission from objects that constitute galactic ecosystems. These include supernova remnants, star-forming regions, superbubbles, galactic outflows (such as the Fermi/eROSITA bubbles in the Milky Way and their analogs in other galaxies), the Circumgalactic Medium in the Milky Way and other galaxies, and the Intergalactic Medium at the outskirts and beyond the confines of galaxies and clusters. LEM's 1-2 eV spectral resolution in the 0.2-2 keV band will make it possible to disentangle the faintest emission lines in those objects from the bright Milky Way foreground, providing groundbreaking measurements of the physics of these plasmas, from temperatures, densities, chemical composition to gas dynamics. While LEM's main focus is on galaxy formation, it will provide transformative capability for all classes of astrophysical objects, from the Earth's magnetosphere, planets and comets to the interstellar medium and X-ray binaries in nearby galaxies, AGN, and cooling gas in galaxy clusters. In addition to pointed observations, LEM will perform a shallow all-sky survey that will dramatically expand the discovery space.

astro-ph.IM↗
arXiv2022

Space Plasma Physics Science Opportunities for the Lunar Orbital Platform -Gateway

The Lunar Orbital Platform-Gateway (LOP-Gateway, or simply Gateway) is a crewed platform that will be assembled and operated in the vicinity of the Moon by NASA and international partner organizations, including ESA, starting from the mid-2020s. It will offer new opportunities for fundamental and applied scientific research. The Moon is a unique location to study the deep space plasma environment. Moreover, the lunar surface and the surface-bounded exosphere are interacting with this environment, constituting a complex multi-scale interacting system. This paper examines the opportunities provided by externally mounted payloads on the Gateway in the field of space plasma physics, heliophysics and space weather, but also examines the impact of the space environment on an inhabited platform in the vicinity of the Moon. It then presents the conceptual design of a model payload, required to perform these space plasma measurements and observations. It results that the Gateway is very well-suited for space plasma physics research. It allows a series of scientific objectives with a multidisciplinary dimension to be addressed.

physics.space-ph↗
arXiv2022

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR, browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters. Finally we briefly discuss on the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, and touch on communication and outreach activities, the consortium organisation, and finally on the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. (abridged).

astro-ph.IM↗
arXiv2022

The SMILE mission

This chapter describes the SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) mission, currently under development as a joint project of the European Space Agency and the Chinese Academy of Sciences. SMILE aims to study the solar wind coupling with the terrestrial magnetosphere in a very novel and global way, by imaging the Earth's magnetosheath and cusps in X-rays emitted when high charge-state solar wind ions exchange charges with exospheric neutrals. SMILE combines this with simultaneous UV imaging of the northern aurora and in-situ plasma and magnetic field measurements of the magnetosheath and solar wind while flying in a highly elliptical northern polar orbit. In this chapter, after a brief introduction to the science that SMILE is targeted to investigate, the payload and the spacecraft, and progress in their development, are described. The mission operations in space, the ground segment and the scientific preparations that will ensure the optimal exploitation of SMILE measurements are also presented. The international space plasma and planetary communities are looking forward to the step change that SMILE will provide by making visible our invisible terrestrial magnetosphere.

physics.space-ph↗
arXiv2022

SMILE: A novel way to explore solar-terrestrial interactions

This chapter describes the scientific motivations that led to the development of the SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) mission. The solar wind coupling with the terrestrial magnetosphere is a key link in Sun-Earth interactions. In-situ missions can provide detailed observations of plasma and magnetic field conditions in the solar wind and the magnetosphere, but leave us still unable to fully quantify the global effects of the drivers of Sun-Earth connections, and to monitor their evolution. This information is essential to develop a comprehensive understanding of how the Sun controls the Earth's plasma environment and space weather. SMILE offers a new approach to global monitoring of geospace by imaging the magnetosheath and cusps in X-rays emitted when high charge-state solar wind ions exchange charges with exospheric neutrals. SMILE combines this with simultaneous UV imaging of the northern aurora and in-situ plasma and magnetic field measurements in the magnetosheath and solar wind from a highly elliptical northern polar orbit. In this chapter the science that SMILE will explore and the scientific preparations that will ensure the optimal exploitation of SMILE measurements are presented.

physics.space-ph↗
arXiv2022

Detection of an Unidentified Soft X-ray Emission Feature in NGC 5548

NGC~5548 is an X-ray bright Seyfert 1 active galaxy. It exhibits a variety of spectroscopic features in the soft X-ray band, including in particular the absorption by the AGN outflows of a broad range of ionization states, with column densities up to 1E27 /m^2, and having speeds up to several thousand kilometers per second. The known emission features are in broad agreement with photoionized X-ray narrow and broad emission line models. We report on an X-ray spectroscopic study using 1.1 Ms XMM-Newton and 0.9 Ms Chandra grating observations of NGC 5548 spanning two decades. The aim is to search and characterize any potential spectroscopic features in addition to the known primary spectral components that are already modeled in high precision. We detect a weak unidentified excess emission feature at 18.4 Angstrom (18.1 Angstrom in the restframe). The feature is seen at >5 sigma statistical significance taking into account the look elsewhere effect. No known instrumental issues, atomic transitions, and astrophysical effects can explain this excess. The observed intensity of the possible feature seems to anti-correlate in time with the hardness ratio of the source. However, the variability might not be intrinsic, it might be caused by the time-variable obscuration by the outflows. An intriguing possibility is the line emission from charge exchange between a partially ionized outflow and a neutral layer in the same outflow, or in the close environment. Other possibilities, such as emission from a highly-ionized component with high outflowing speed, cannot be fully ruled out.

astro-ph.HE↗
arXiv2022

Observation and origin of non-thermal hard X-rays from Jupiter

Electrons accelerated on Earth by a rich variety of wave scattering or stochastic processes generate hard non-thermal X-ray bremsstrahlung up to >~ 1 MeV and power Earth's various types of aurorae. Although Jupiter's magnetic field is an order of magnitude larger than Earth's, space-based telescopes have previously detected X-rays only up to ~7 keV. On the basis of theoretical models of the Jovian auroral X-ray production, X-ray emission in the ~2-7 keV band has been interpreted as thermal (arising from electrons characterized by a Maxwell-Boltzmann distribution) bremsstrahlung. Here we report the observation of hard X-rays in the 8-20 keV band from the Jovian aurorae, obtained with the NuSTAR X-ray observatory. The X-rays fit to a flat power-law model with slope 0.60+/-0.22 - a spectral signature of non-thermal, hard X-ray bremsstrahlung. We determine the electron flux and spectral shape in the keV to MeV energy range using coeval in situ measurements by the Juno spacecraft's JADE and JEDI instruments. Jovian electron spectra of the form we observe have previously been interpreted to arise in stochastic acceleration, rather than coherent acceleration by electric fields. We reproduce the X-ray spectral shape and approximate flux observed by NuSTAR, and explain the non-detection of hard X-rays by Ulysses, by simulating the non-thermal population of electrons undergoing precipitating electron energy loss, secondary electron generation and bremsstrahlung emission in a model Jovian atmosphere. The results highlight the similarities between the processes generating hard X-ray auroras on Earth and Jupiter, which may be occurring on Saturn, too.

astro-ph.EP↗
arXiv2021

Changing-look event in NGC 3516: continuum or obscuration variability?

The Seyfert-1 galaxy NGC 3516 has undergone major spectral changes in recent years. In 2017 we obtained Chandra, NuSTAR, and Swift observations during its new low-flux state. Using these observations we model the spectral energy distribution (SED) and the intrinsic X-ray absorption, and compare the results with those from historical observations taken in 2006. We thereby investigate the effects of the changing-look phenomenon on the accretion-powered radiation and the ionized outflows. Compared to its normal high-flux state in 2006, the intrinsic bolometric luminosity of NGC 3516 was lower by a factor of 4 to 8 during 2017. Our SED modeling shows a significant decline in the luminosity of all the continuum components from the accretion disk and the X-ray source. As a consequence, the reprocessed X-ray emission lines have also become fainter. The Swift monitoring of NGC 3516 shows remarkable X-ray spectral variability on short (weeks) and long (years) timescales. We investigate whether this variability is driven by obscuration or the intrinsic continuum. We find that the new low-flux spectrum of NGC 3516, and its variability, do not require any new or variable obscuration, and instead can be explained by changes in the ionizing SED that result in lowering of the ionization of the warm-absorber outflows. This in turn induces enhanced X-ray absorption by the warm-absorber outflows, mimicking the presence of new obscuring gas. Using the response of the ionized regions to the SED changes, we place constraints on their density and location.

astro-ph.HE↗
arXiv2021

Transient obscuration event captured in NGC~3227 II. Warm absorbers and obscuration events in archival XMM-Newton and NuSTAR observations

The relation between warm absorber (WA) outflows of AGN and nuclear obscuration activities caused by optically-thick clouds (obscurers) crossing the line of sight is unclear. NGC 3227 is a suitable target to study the properties of both WAs and obscurers, because it matches the following selection criteria: WAs in both ultraviolet (UV) and X-rays, suitably variable, bright in UV and X-rays, good archival spectra for comparing with the obscured spectra. To investigate WAs and obscurers of NGC~3227, we used a broadband spectral-energy-distribution model built in our Paper I and the photoionization code of SPEX software to fit archival XMM-Newton and NuSTAR observations in 2006 and 2016. Using unobscured observations, we find four WAs with different ionization states (log$ξ$ [erg cm/s]~-1.0, 2.0, 2.5, 3.0). The highest-ionization WA has a higher hydrogen column density (~$10^{22}$/cm$^2$) than the other three WAs (~$10^{21}$/cm$^2$). Their outflow velocities range from 100 to 1300 km/s, and show a positive correlation with the ionization parameter. These WAs are estimated to be between the outer broad-line-region (BLR) and the narrow line region. Besides, we find an X-ray obscuration event in 2006, which was missed by previous studies. It can be explained by a single obscurer. We also study the previously published obscuration event in 2016, which needs two obscurers in the fit. A high-ionization obscurer (log$ξ$~2.80; covering factor $C_f$~30%) only appears in 2016, which has a high column density (~$10^{23}$/cm$^2$). A low-ionization obscurer (log$ξ$~1.0-1.9; $C_f$~20%-50%) exists in both 2006 and 2016, which has a lower column density (~$10^{22}$/cm$^2$). These obscurers are estimated to be in the BLR by their crossing time of transverse motions. The obscurers and WAs of NGC 3227 have different distances and number densities, which indicate that they might have different origins.

astro-ph.GA↗
arXiv2020

X-ray Studies of Planetary Systems: A 2020 Decadal Survey White Paper

Whether it is fluorescence emission from asteroids and moons, solar wind charge exchange from comets, exospheric escape from Mars, pion reactions on Venus, sprite lighting on Saturn, or the Io plasma torus in the Jovian magnetosphere, the Solar System is surprisingly rich and diverse in X-ray emitting objects. The compositions of diverse planetary bodies are of fundamental interest to planetary science, providing clues to the formation and evolutionary history of the target bodies and the solar system as a whole. X-ray fluorescence (XRF) lines, triggered either by solar X-rays or energetic ions, are intrinsic to atomic energy levels and carry an unambiguous signature of the elemental composition of the emitting bodies. All remote-sensing XRF spectrometers used so far on planetary orbiters have been collimated instruments, with limited achievable spatial resolution, and many have used archaic X-ray detectors with poor energy resolution. Focusing X-ray optics provide true spectroscopic imaging and are used widely in astrophysics missions, but until now their mass and volume have been too large for resource-limited in-situ planetary missions. Recent advances in X-ray instrumentation such as the Micro-Pore Optics used on the BepiColombo X-ray instrument (Fraser et al., 2010), Miniature X-ray Optics (Hong et al., 2016) and highly radiation tolerant CMOS X-ray sensors (e.g., Kenter et al., 2012) enable compact, yet powerful, truly focusing X-ray Imaging Spectrometers. Such instruments will enable compositional measurements of planetary bodies with much better spatial resolution and thus open a large new discovery space in planetary science, greatly enhancing our understanding of the nature and origin of diverse planetary bodies. Here, we discuss many examples of the power of XRF to address key science questions across the solar system.

astro-ph.IM↗
arXiv2019

Charge exchange emission and cold clumps in multi-phase galactic outflows

Large-scale outflows from starburst galaxies are multi-phase, multi-component fluids. Charge-exchange lines which originate from the interfacing surface between the neutral and ionised components are a useful diagnostic of the cold dense structures in the galactic outflow. From the charge-exchange lines observed in the nearby starburst galaxy M82, we conduct surface-to-volume analyses and deduce that the cold dense clumps in its galactic outflow have flattened shapes, resembling a hamburger or a pancake morphology rather than elongated shapes. The observed filamentary H$α$ features are therefore not prime charge-exchange line emitters. They are stripped material torn from the slow moving dense clumps by the faster moving ionised fluid which are subsequently warmed and stretched into elongated shapes. Our findings are consistent with numerical simulations which have shown that cold dense clumps in galactic outflows can be compressed by ram pressure, and also progressively ablated and stripped before complete disintegration. We have shown that some clumps could survive their passage along a galactic outflow. These are advected into the circumgalactic environment, where their remnants would seed condensation of the circumgalactic medium to form new clumps. The infall of these new clumps back into the galaxy and their subsequent re-entrainment into the galactic outflow form a loop process of galactic material recycling.

astro-ph.GA↗
arXiv2019

The in-situ exploration of Jupiter's radiation belts (A White Paper submitted in response to ESA's Voyage 2050 Call)

Jupiter has the most energetic and complex radiation belts in our solar system. Their hazardous environment is the reason why so many spacecraft avoid rather than investigate them, and explains how they have kept many of their secrets so well hidden, despite having been studied for decades. In this White Paper we argue why these secrets are worth unveiling. Jupiter's radiation belts and the vast magnetosphere that encloses them constitute an unprecedented physical laboratory, suitable for both interdisciplinary and novel scientific investigations: from studying fundamental high energy plasma physics processes which operate throughout the universe, such as adiabatic charged particle acceleration and nonlinear wave-particle interactions; to exploiting the astrobiological consequences of energetic particle radiation. The in-situ exploration of the uninviting environment of Jupiter's radiation belts present us with many challenges in mission design, science planning, instrumentation and technology development. We address these challenges by reviewing the different options that exist for direct and indirect observation of this unique system. We stress the need for new instruments, the value of synergistic Earth and Jupiter-based remote sensing and in-situ investigations, and the vital importance of multi-spacecraft, in-situ measurements. While simultaneous, multi-point in-situ observations have long become the standard for exploring electromagnetic interactions in the inner solar system, they have never taken place at Jupiter or any strongly magnetized planet besides Earth. We conclude that a dedicated multi-spacecraft mission to Jupiter's radiation belts is an essential and obvious way forward and deserves to be given a high priority in ESA's Voyage 2050 programme.

physics.space-ph↗
arXiv2019

Suzaku observation of Jupiter's X-rays around solar maximum

We report on results of imaging and spectral studies of X-ray emission from Jupiter observed by Suzaku. In 2006 Suzaku had found diffuse X-ray emission in $1\unicode{x2013}5$ keV associated with Jovian inner radiation belts. It has been suggested that the emission is caused by the inverse-Compton scattering by ultra-relativistic electrons ($ \sim 50 $ MeV) in Jupiter's magnetosphere. To confirm the existence of this emission and to understand its relation to the solar activity, we conducted an additional Suzaku observation in 2014 around the maximum of the 24th solar cycle. As a result, we successfully found again the diffuse emission around Jupiter in $1\unicode{x2013}5$ keV and also point-like emission in $0.4\unicode{x2013}1$ keV. The luminosity of the point-like emission which was probably composed of solar X-ray scattering, charge exchange, or auroral bremsstrahlung emission increased by a factor of $ \sim 5$ with respect to 2006, most likely due to an increase of the solar activity. The diffuse emission spectrum in the $1\unicode{x2013}5$ keV band was well-fitted with a flat power-law function ($ Γ= 1.4 \pm 0.1 $) as in the past observation, which supported the inverse-Compton scattering hypothesis. However, its spatial distribution changed from $ \sim 12 \times 4 $ Jovian radius (Rj) to $ \sim 20 \times 7 $ Rj. The luminosity of the diffuse emission increased by a smaller factor of $ \sim 3 $. This indicates that the diffuse emission is not simply responding to the solar activity, which is also known to cause little effect on the distribution of high-energy electrons around Jupiter. Further sensitive study of the spatial and spectral distributions of the diffuse hard X-ray emission is important to understand how high-energy particles are accelerated in Jupiter's magnetosphere.

astro-ph.EP↗
arXiv2019

X-ray Studies of Exoplanets: A 2020 Decadal Survey White Paper

Over the last two decades, the discovery of exoplanets has fundamentally changed our perception of the universe and humanity's place within it. Recent work indicates that a solar system's X-ray and high energy particle environment is of fundamental importance to the formation and development of the atmospheres of close-in planets such as hot Jupiters, and Earth-like planets around M stars. X-ray imaging and spectroscopy provide powerful and unique windows into the high energy flux that an exoplanet experiences, and X-ray photons also serve as proxies for potentially transfigurative coronal mass ejections. Finally, if the host star is a bright enough X-ray source, transit measurements akin to those in the optical and infrared are possible and allow for direct characterization of the upper atmospheres of exoplanets. In this brief white paper, we discuss contributions to the study of exoplanets and their environs which can be made by X-ray data of increasingly high quality that are achievable in the next 10--15 years.

astro-ph.EP↗
arXiv2019

X-rays Studies of the Solar System

X-ray observatories contribute fundamental advances in Solar System studies by probing Sun-object interactions, developing planet and satellite surface composition maps, probing global magnetospheric dynamics, and tracking astrochemical reactions. Despite these crucial results, the technological limitations of current X-ray instruments hinder the overall scope and impact for broader scientific application of X-ray observations both now and in the coming decade. Implementation of modern advances in X-ray optics will provide improvements in effective area, spatial resolution, and spectral resolution for future instruments. These improvements will usher in a truly transformative era of Solar System science through the study of X-ray emission.

astro-ph.HE↗
arXiv2018

The Athena X-ray Integral Field Unit

The X-ray Integral Field Unit (X-IFU) is the high resolution X-ray spectrometer of the ESA Athena X-ray observatory. Over a field of view of 5' equivalent diameter, it will deliver X-ray spectra from 0.2 to 12 keV with a spectral resolution of 2.5 eV up to 7 keV on ~5 arcsecond pixels. The X-IFU is based on a large format array of super-conducting molybdenum-gold Transition Edge Sensors cooled at about 90 mK, each coupled with an absorber made of gold and bismuth with a pitch of 249 microns. A cryogenic anti-coincidence detector located underneath the prime TES array enables the non X-ray background to be reduced. A bath temperature of about 50 mK is obtained by a series of mechanical coolers combining 15K Pulse Tubes, 4K and 2K Joule-Thomson coolers which pre-cool a sub Kelvin cooler made of a 3He sorption cooler coupled with an Adiabatic Demagnetization Refrigerator. Frequency domain multiplexing enables to read out 40 pixels in one single channel. A photon interacting with an absorber leads to a current pulse, amplified by the readout electronics and whose shape is reconstructed on board to recover its energy with high accuracy. The defocusing capability offered by the Athena movable mirror assembly enables the X-IFU to observe the brightest X-ray sources of the sky (up to Crab-like intensities) by spreading the telescope point spread function over hundreds of pixels. Thus the X-IFU delivers low pile-up, high throughput (>50%), and typically 10 eV spectral resolution at 1 Crab intensities, i.e. a factor of 10 or more better than Silicon based X-ray detectors. In this paper, the current X-IFU baseline is presented, together with an assessment of its anticipated performance in terms of spectral resolution, background, and count rate capability. The X-IFU baseline configuration will be subject to a preliminary requirement review that is scheduled at the end of 2018.

astro-ph.IM↗
arXiv2016

Multi-wavelength campaign on NGC7469 I. The rich 640 ks RGS spectrum

Outflows in active galaxies (AGNs) are common, although their launching mechanism, location, and physical impact on the host galaxy remain controversial. We conducted a multiwavelength six-month campaign to observe the nearby Seyfert galaxy NGC 7469 with several observatories in order to better understand and quantify the outflow in this AGN. We report on the time-integrated line-resolved X-ray spectrum of NGC 7469 obtained with the Reflection Grating Spectrometer (RGS) on board XMM-Newton. We use the RGS spectrum to discern the many AGN outflow components. A global fit is applied to obtain their physical parameters. We find that the AGN wind can be well described by three narrow velocity components at -650, -950, and -2050 km/s. The RGS clearly resolves the -20 50 km/s component in C5+ Ly$α$, while the -650 km/s and -950 km/s velocities are blended. Similar velocities are resolved in the UV. The H-equivalent column densities of these components are, respectively, NH = 7x10^20, 2.2x10^21, and 10^20 cm^-2, for a total of 3x10^21 cm^-2. The -650 km/s component shows a broad ionisation distribution. We identify a photo-ionised emission component blue-shifted by -450 km/s which we ascribe to the same outflow that produces the absorption lines. The elemental abundance ratios of C, N, Ne, S, and Fe to O in the outflow tend to be between 1 - 2 times solar. Preliminary estimates of the absorber distance from the AGN center suggest it is at least a few pc away from the center, but more advanced methods need to be applied in order to obtain better constraints. The complex X-ray spectrum of NGC 7469 demonstrates the richness of high energy phenomena taking place in AGN cores. The subtle spectroscopic differences between the various components require deep, high-resolution observations, such as the present RGS spectrum, if one is to resolve them and perform quantitative plasma diagnostics.

astro-ph.HE↗