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In some semi-detached binary systems, the donor star may transfer mass to the companion at a very high rate. We propose that, at sufficiently high mass-transfer rates such that the accretion disk around the companion becomes geometrically thick (or advection-dominated) near the disk outer radius, a large fraction of the transferred mass will be lost through the outer Lagrangian (L2) point, as a result of the excessive energy generated by viscous heating that cannot be efficiently radiated away. A physical model is constructed where the L2 mass loss fraction is given by the requirement that the remaining material in the disk has Bernoulli number equal to the L2 potential energy. Our model predicts significant L2 mass loss at mass-transfer rates exceeding a few times 10^{-4} Msun/yr. An equatorial circum-binary outflow (CBO) is formed in these systems. Implications for the orbital evolution and the observational appearance are discussed. In particular, (1) rapid angular momentum loss from the system tends to shrink the orbit and hence may increase the formation rate of mergers and gravitational-wave sources; (2) photons from the hot disk wind are reprocessed by the CBO into longer wavelength emission in the infrared bands, consistent with Spitzer observations of some ultra-luminous X-ray sources., MNRAS in press, 14 pages, 7 figures, plus appendix. Codes available here: https://github.com/wenbinlu/L2massloss

The nuclear transient AT2019cuk/Tick Tock/SDSS J1430+2303 has been suggested to harbor a supermassive black hole (SMBH) binary near coalescence. We report results from high-cadence NICER X-ray monitoring with multiple visits per day from January-August 2022, as well as continued optical monitoring during the same time period. We find no evidence of periodic/quasi-periodic modulation in the X-ray, UV, or optical bands, however we do observe exotic hard X-ray variability that is unusual for a typical AGN. The most striking feature of the NICER light curve is repetitive hard (2-4 keV) X-ray flares that result in distinctly harder X-ray spectra compared to the non-flaring data. In its non-flaring state, AT2019cuk looks like a relatively standard AGN, but it presents the first case of day-long, hard X-ray flares in a changing-look AGN. We consider a few different models for the driving mechanism of these hard X-ray flares, including: (1) corona/jet variability driven by increased magnetic activity, (2) variable obscuration, and (3) self-lensing from the potential secondary SMBH. We prefer the variable corona model, as the obscuration model requires rather contrived timescales and the self-lensing model is difficult to reconcile with a lack of clear periodicity in the flares. These findings illustrate how important high-cadence X-ray monitoring is to our understanding of the rapid variability of the X-ray corona and necessitate further high-cadence, multi-wavelength monitoring of changing-look AGN like AT2019cuk to probe the corona-jet connection., 23 pages, 13 figures, 1 table, accepted for publication in ApJL

The scientific community defines the XMM-Newton observing program through a peer review process. This process is organized by the XMM-Newton Project Scientist supported by the Science Operations Centre, and with minimal interaction between mission staff and the reviewing scientists, e.g. panels organize their meeting by themselves and meet at places of their choice. It is important that the scientific community consider the review as their review and the decisions as their decisions. Although the review requires time and effort, panel members consider it a very positive scientific experience and are happy to help again in later years. The peer review is the most important link between the mission and the scientific community. It plays a fundamental role in ensuring diversity, equity, and inclusion and acts as a motor for scientific developments and breakthrough discoveries.

Contributed talk in "Exploring the Hot and Energetic Universe: the 3rd scientific conference dedicated to the Athena X-ray Observatory". This presentation is based on the published paper "Chemical enrichment in the cool core of the Centaurus cluster of galaxies" (Fukushima et al., 2022, MNRAS, 514, 4222)., This work is financially supported by the Japanese Society for the Promotion of Science (JSPS) through the Grant-in-Aid for JSPS Fellows grant No. 21J21541 (KF).

The A3391/95 clusters harbor bright central radio sources, which makes them ideal objects to probe the ICM-AGN interaction. The future JAXA/NASA/ESA mission, the X-Ray Imaging and Spectroscopy Mission (XRISM) will enable us to resolve line emission and the motion of the ICM affected by AGN feedback. Through simulation using cluster properties obtained from eROSITA and XMM-Newton, a forecast of the best observing strategy for XRISM high-resolution spectroscopy will be made. Given the complexity of the system, we will probe their merger state, as well. We further extend the central AGN-ICM study to a larger sample, namely using the first eROSITA All-Sky Survey (eRASS1) cluster sample in the EMU pilot field using the Australian ASKAP radio telescopes. We present preliminary results of the X-ray morphological properties of this sample. Athena will complete the AGN-ICM study, for instance, to investigate in great detail the chemical distribution and central cluster gas motion due to the central AGN feedback.

The X-ray relativistically broadened fluorescent iron line and the Compton hump reflected from the innermost accretion flows around a supermassive black hole (SMBH) can be used to probe black hole spin rates. In particular, X-ray spectroscopy helps us measure the SMBH spins in nearby Seyfert 1 galaxies whose central innermost regions are not largely blocked by the dusty torus. In this study, a MCMC-based method is employed to probe the best-fit parameters of a relativistic reflection model in X-ray archival data of a sample of nearby Seyfert 1 active galaxies observed by the XMM-Newton and NuSTAR space telescopes. Future high-resolution X-ray spectroscopic observations with the Advanced Telescope for High-ENergy Astrophysics (Athena) as demonstrated by simulations will certainly allow us to put better constraints on SMBH spins, which have profound implications for our understanding of the mechanism behind ultra-fast outflows launched at the centers of Seyfert 1 galaxies.

The EU funded XMM2Athena project aims at developing and testing new methods and software to allow the community to follow the X-ray transient sky in quasi-real time, identify multiwavelength/messenger counterparts of the sources detected with XMM-Newton and determine their nature using advanced machine learning methods and probe the faintest sources using innovative stacking and detection algorithms. Within this project we developed software to perform automated fits based on a Bayesian approach. We did spectral fits of the 319565 detections with spectra in the 4XMM-DR11 catalogue using a simple absorbed powerlaw model. Furthermore, we fit combined spectra for the 30325 sources that have been observed more than once, based on the XMM-Newton stacked catalogue, using an absorbed powerlaw as well as an absorbed blackbody model. We performed quality checks and investigated the distributions of the spectral parameters. Here we will present the results of our efforts and promote our catalogues to encourage the community to make use of them.&nbsp

We report on the detection of MKT J174641.0$-$321404, a new radio transient found in untargeted searches of wide-field MeerKAT radio images centred on the black hole X-ray binary H1743$-$322. MKT J174641.0$-$321404 is highly variable at 1.3 GHz and was detected three times during 11 observations of the field in late 2018, reaching a maximum flux density of 590 $\pm$ 60 $\mu$Jy. We associate this radio transient with a high proper motion, M dwarf star SCR~1746$-$3214 12 pc away from the Sun. Multiwavelength observations of this M dwarf indicate flaring activity across the electromagnetic spectrum, consistent with emission expected from dMe stars, and providing upper limits on quiescent brightness in both the radio and X-ray regimes. \textit{TESS} photometry reveals a rotational period for SCR~1746$-$3214 of $0.2292 \pm 0.0025$ days, which at its estimated radius makes the star a rapid rotator, comparable to other low mass systems. Dedicated spectroscopic follow up confirms the star as a mid-late spectral M dwarf with clear magnetic activity indicated by strong H$\alpha$ emission. This transient's serendipitous discovery by MeerKAT, along with multiwavelength characterisation, make it a prime demonstration of both the capabilities of the current generation of radio interferometers and the value of simultaneous observations by optical facilities such as MeerLICHT. Our results build upon the literature of of M dwarfs' flaring behaviour, particularly relevant to the habitability of their planetary systems., Comment: Accepted to MNRAS, 11 pages, 9 figures

Context: Multi-wavelength time domain analysis of Young Stellar Objects (YSOs) is a relatively new method within star formation research which may lead to better constraints on fundamental star formation processes. Such young objects are known to be strong X-ray emitters whereas in the far-infrared we are mainly probing the protoplanetary disk of these YSOs. Protostars are known to be variable in the X-ray, likely due to magnetic coronal activity. Far-infrared variability is still little understood and has only been detected once, but the possibility of finding variability in both wavelengths will allow us to compare processes that may be happening in the corona (X-ray) and the disk (far-infrared). Aims: Here we present the first simultaneous XMM-Newton and Herschel short-timescale variability analysis of the YSOs in the Coronet Cluster. Located in the Corona Australis Molecular Cloud complex, this is a young (

In this report we discuss topological studies of large scale structure of the Universe (LSS) from XMM-Newton, Sloan Digital Sky Survey and simulated data of galaxy distribution. Early works in this mentioned field were based on genus statistics, which is averaged curvature of isosurface of smoothed density field. Later, significant number of other methods was developed. This comprise Euler characteristics, Minkowski functionals, Voronoi clustering, alpha shapes, Delanuay tesselation, Morse theory, Hessian matrix and Soneira-Peebles models. In practice, modern topology methods are reducedto calculation of the three Betti numbers which shall be interpreted as a number of galaxy clusters, filaments and voids. Such an approach was applied by different authors both for simulated and observed LSS data. Topology methods are generally verified using LSS simulations. Observational data normally includes SDSS, CFHTLS and other surveys. These data have many systematical and statistical errors and gaps. Furthermore, there is also a problem of underlying dark matter distribution. The situation is not better in relation to calculations of the power spectrum and its power law index which does not provide a clear picture as well. In this work we propose some tools to solve above problems. First, we performed topology description of simple LSS models such as cubic, graphite-like and random Gaussian distribution of matter. Our next idea is to set a task for LSS topology assessment using X-ray observations of the galaxies. Although, here could be a major complication due to current lack of detected high energy emitting galaxies. Nevertheless, we are expecting to get sufficient results in the future encouraging comprehensive X-ray data. Here we present analysis of statistical moments for four galaxy samples and compare them with the behavior of Betti numbers. Finally, we consider the options of applying artificial neural networks to observed galaxies and fill the data deficiency. This shall enable to define topology at least for superimposed superclusters and other LSS elements., У цiй роботi ми розглянули топологiчнi дослiдження великомасштабної структури всесвiту (LSS) з використанням даних обсерваторiй XMM-Newton, SDSS та змодельованих розподiлiв галактик. Раннi роботи у зазначенiй галузi базувалися на типовiй статистицi, що є усередненою кривизною iзоповерхнi згладженого поля щiльностi. Пiзнiше було розроблено значну кiлькiсть iнших методiв. Сюди входять характеристики Ейлера, функцiонали Мiнковського, кластеризацiя Вороно- го, альфа-форми, теселяцiя Делано, теорiя Морзе, матрицi Геса та моделi Сонейра-Пiблза. На практи- цi сучаснi методи топологiї зводяться до обчислення трьох чисел Беттi, якi слiд iнтерпретувати як рядскупчень галактик, фiламентiв та порожнин. Такий пiдхiд був застосований рiзними авторами як до змодельованих, так i до спостережуваних даних LSS. Методи топологiї зазвичай перевiряються на моделюваннi LSS, а данi спостережень зазвичай включають SDSS, CFHTLS та iншi огляди неба. Цi данi мають багато систематичних та статистичних помилок та недостатнью кiлькiсть iнформацiї. Бiльш того, iснує також проблема розподiлу темної матерiї. Не кращий стан i з розрахунками спектру потужностi та степеневого коефiцiнту потужностi, якi також не дають чiткої картини. Ми пропонуємо деякi iнструменти для вирiшення вищевказаних проблем. По -перше, нас цiкавить опис топологiїпростих моделей LSS, таких як кубiчна, графiтова та випадкова гаусiвська модель розподiлу речовини. Наша наступна iдея це поставити задачу оцiнити топологiю LSS за допомогою рентгенiвських спостережень галактик. Хоча тут може виникнути серйозне ускладнення через поточну вiдсутнiсть виявлених галактик, що випромiнюють високi енергiї. Тим не менш, ми очiкуємо в майбутньому отримати достатнi результати, заохочуючи вичерпнi рентгенiвськi данi. У данiй роботi представлено аналiз статистичних моментiв для чотирьох вибiрок 2 Odessa Astronomical Publications, vol. 34 (2021) галактик i їх порiвняння з поведiнкою чисел Беттi. Нарештi, ми розглядаємо можливiсть застосування штучної нейронної мережi до спостережуваних галактик i заповнити дефiцит даних. Це дозволить визначити топологiю принаймнi для накладених суперкластерiв та iнших елементiв великомасштабної структури всесвiту.

The X-ray satellite XMM-Newton, also called the X-ray Multi Mirror Mission, is a highly successful mission of the European Space Agency (ESA). It was launched in 1999 and is expected to continue to provide high sensitivity observations in the soft to mid-energy X-ray range for several more years to come. This thesis is dedicated to two XMM-related topics. Three X-ray cameras on board the satellite together constitute XMM-Newton’s European Photon Imaging Camera (EPIC). Differences between the fluxes measured with the individual cameras indicated a discrepancy in their effective area calibration, which sets a limit to the quality that the scientific analysis of XMM data can have. Until now, a reliable correction of the effective area calibration to reconcile the three EPIC cameras is missing. The first part of this thesis is concerned with the further development of the CORRAREA tool included in the standard data reduction and analysis software for XMM-Newton, pursuing the aim of making it fit to serve as a default correction for the EPIC on-axis effective area calibration in the future. CORRAREA applies an energy-dependent, multiplicative correction factor to the data, based on correction functions determined by empirical cross-calibration of the EPIC cameras with the stacked residual ratio method. The underlying procedure was revised and extended in the scope of this work to suit the purpose of a default correction tool. A script package was developed to largely automate the necessary steps for validation purposes and future updates. From the hundreds of thousands of source detections in the XMM database, 163 sources were identified as being suitable to be included in the analysis to determine the required correction functions. The dependence of the results on different factors was investigated for validation, revealing that the combination of different XMM science modes requires an adjustment of the originally applied stacking method. New correction functions were determined for an updated, recalibrated non-default application. It was successfully shown that the procedure performed with the developed scripts can, in addition, be used for an independent validation of other calibration works. The presented routine also offers the potential to be extended to involve a cross-calibration with instruments on other X-ray observatories in the future. In the second part of this thesis, the first search for a compact object associated with the Galactic supernova remnant (SNR) G96.0+2.0, using an XMM-Newton observation, is presented. Compact objects are astronomical objects with very high densities and include neutron stars (NSs), which are prominent X-ray sources. NSs are the most dense objects that can be directly observed and are, thus, extremely interesting for the study of superdense matter. An identified SNR-NS-pair can provide information about each of the two objects that would otherwise be inaccessible. A special focus was set on searching for one particular kind of compact object, a so-called central compact object (CCO), which is an isolated, purely thermally emitting NS located in the centre of a SNR. Because CCOs offer an undisturbed view onto their surface, they are considered ideal targets to obtain constraints on NS parameters and the properties of their superdense matter. Both, identifying SNR-NS-pairs and increasing the small number of known CCOs, are an important contribution to the study of NSs and of the fundamental physics concerning superdense matter. A source detection was carried out for each image in the XMM observation of G96.0+2.0 and 22 X-ray point sources were identified. A possible NS nature of the individual sources was investigated by conducting a cross-match with optical catalogues to search for potential counterparts, by performing a spectral and timing analysis for each source and by analysing their X-ray-to-optical flux ratios as well as their positions in a hardness ratio diagram. The results led to the exclusion of the possibility of the SNR having an associated CCO. In addition, 17 of the identified X-ray point sources could be dismissed as potential candidates for any type of associated NS altogether. Of the remaining sources, one was found to be a particularly promising candidate for a potentially associated NS, with all characteristics being consistent with a NS nature.

Our understanding of how AGN feedback operates in galaxy clusters has improved in recent years owing to large efforts in multi-wavelength observations and hydrodynamical simulations. However, it is much less clear how feedback operates in galaxy groups, which have shallower gravitational potentials. In this work, using very deep VLA and new MeerKAT observations from the MIGHTEE survey, we compiled a sample of 247 X-ray selected galaxy groups detected in the COSMOS field. We have studied the relation between the X-ray emission of the intra-group medium and the 1.4 GHz radio emission of the central radio galaxy. For comparison, we have also built a control sample of 142 galaxy clusters using ROSAT and NVSS data. We find that clusters and groups follow the same correlation between X-ray and radio emission. Large radio galaxies hosted in the centres of groups and merging clusters increase the scatter of the distribution. Using statistical tests and Monte-Carlo simulations, we show that the correlation is not dominated by biases or selection effects. We also find that galaxy groups are more likely than clusters to host large radio galaxies, perhaps owing to the lower ambient gas density or a more efficient accretion mode. In these groups, radiative cooling of the ICM could be less suppressed by AGN heating. We conclude that the feedback processes that operate in galaxy clusters are also effective in groups., Comment: 15 pages, 14 figures

Population studies of the extragalactic objects are a major part of the universe large-scale structure study. Apart from radio, infrared, and visible wavelength bands, observations and further identification of extragalactic objects such as galaxies, quasars, blazers, liners, and active star burst regions are also conducted in the X-ray and gamma bands. In this paper we make identification and cross-correlate of the infrared and X-ray observational data, build a distribution of a selected sample sources by types and attempted to analyze types of the extragalactic objects at distances up to z = 0.1 using observational data of relevant space observatories. Data from a leading X-ray space observatory XMM-Newton were used to compile the largest catalog of X-ray sources. Current version of XMM SSC (Serendipitous Source Catalog) contains more than half a million sources. In our previous works we selected and analyzed a sample of 5021 X-ray galaxies observed by XMM-Newton. Identification and classification of these sources is essential next step of the study. In this study we used infrared apparent magnitudes from WISE catalog of AGN candidates. In 2010 space telescope WISE performed full sky survey in four infrared bands and detected 747 million sources. WISE catalog of AGN candidates amounts 4 million of possible extragalactic sources. We built infrared color-color diagram for our sample of X-ray galaxies and assessed their types using WISE telescope data. In this study we also analyzed large scale structure of the universe (distances up to z=0.1). This analysis revealed Coma galaxy cluster and SDSS Sloan Great Wall. In the further studies we are planning to investigate the distribution of different types of X-ray galaxies within the large-scale structures of the Universe., 8 pages, 5 figures

We studied five XMM-Newton observations of the neutron-star binary 4U 1728$-$34 covering the hard, intermediate and soft spectral states. By jointly fitting the spectra with several reflection models, we obtained an inclination angle of 25$-$53$\deg$ and an iron abundance up to 10 times the solar. From the fits with reflection models, we found that the fluxes of the reflection and the Comptonised components vary inconsistently; since the latter is assumed to be the illuminating source, this result possibly indicates the contribution of the neutron star surface/boundary layer to the disc reflection. As the source evolved from the relatively soft to the intermediate state, the disc inner radius decreased, opposite to the prediction of the standard accretion disc model. We also explore the possible reasons why the supersolar iron abundance is required by the data and found that this high value is probably caused by the absence of the hard photons in the XMM-Newton data., Comment: 14 pages, 6 figures

V. A. Acciari et al., We report multiwavelength observations of the gravitationally lensed blazar QSO B0218+357 in 2016–2020. Optical, X-ray, and GeV flares were detected. The contemporaneous MAGIC observations do not show significant very high energy (VHE; ≳100 GeV) gamma-ray emission. The lack of enhancement in radio emission measured by The Owens Valley Radio Observatory indicates the multizone nature of the emission from this object. We constrain the VHE duty cycle of the source to be, The financial support of the German BMBF, MPG, and HGF; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish Ministerio de Ciencia e Innovación (MICINN) (FPA2017-87859-P, FPA2017-85668-P, FPA2017-82729-C6-5-R, FPA2017-90566-REDC, PID2019-104114RB-C31, PID2019-104114RB-C32, PID2019-105510GB-C31, PID2019-107847RB-C41, PID2019-107847RB-C42, PID2019-107988GB-C22); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-268/16.12.2019 and the Academy of Finland grant nr. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia ‘Severo Ochoa’ SEV-2016-0588 and CEX2019-000920-S, and ‘María de Maeztu’ CEX2019-000918-M, the Unidad de Excelencia ‘María de Maeztu’ MDM-2015-0509-18-2 and the ‘la Caixa’ Foundation (fellowship LCF/BQ/PI18/11630012) and by the CERCA program of the Generalitat de Catalunya; by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project uniri-prirod-18-48; by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3; the Polish National Research Centre grant UMO-2016/22/M/ST9/00382; and by the Brazilian MCTIC, CNPq, and FAPERJ. The Fermi LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat à l’Energie Atomique and the Centre National de la Recherche Scientifique / Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d’Études Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515. We thank Director of Indian Institute of Astrophysics for allotting us observing time with HCT under DDT. We also thank the staff of IAO, Hanle and CREST, Hosakote, that made HCT observations possible. The facilities at IAO and CREST are operated by the Indian Institute of Astrophysics, Bangalore. The Joan Oró Telescope (TJO) of the Montsec Astronomical Observatory (OAdM) is owned by the Catalan Government and operated by the Institute for Space Studies of Catalonia (IEEC). This research has made use of data from the OVRO 40-m monitoring program which was supported in part by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G, and NSF grants AST-0808050 and AST-1109911, and private funding from Caltech and the MPIfR. SK acknowledges support from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme under grant agreement No. 771282. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. This publication makes use of data obtained at the Metsähovi Radio Observatory, operated by Aalto University in Finland. Part of this work is based on archival data, software or online services provided by the Space Science Data Center - ASI.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., Our project MOMO (Multiwavelength observations and modeling of OJ 287) consists of dedicated, dense, long-term flux and spectroscopic monitoring, and deep follow-up observations of the blazar OJ 287 at >13 frequencies from the radio to the X-ray band since late 2015. In particular, we are using Swift to obtain optical-UV-X-ray spectral energy distributions (SEDs) and the Effelsberg telescope to obtain radio measurements between 2 and 40 GHz. MOMO is the densest long-term monitoring of OJ 287 involving X-rays and broad-band SEDs. The theoretical part of the project aims at understanding jet and accretion physics of the blazar central engine in general and the supermassive binary black hole scenario in particular. Results are presented in a sequence of publications and so far included: detection and detailed analysis of the bright 2016/17 and 2020 outbursts and the long-term light curve; Swift, XMM, and NuSTAR spectroscopy of the 2020 outburst around maximum; and interpretation of selected events in the context of the binary black hole scenario of OJ 287 (papers I–IV). Here, we provide a description of the project MOMO, a summary of previous results, the latest results, and we discuss future prospects. © 2021 by the authors. Licensee MDPI, Basel, Switzerland., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

The main purpose of this work is to explore X-ray astronomical data from EPIC cameras on board XMM-Newton observatory by using machine learning techniques. As a result, and depending on the scientific validation, part of the techniques/algorithmts produced could be implemented in future XMM-Newton processing pipeline versions. XMM-Newton is short for X-ray Multi Mirror observatory, and it is one of the main science missions of the European Space Agency. Data collected by XMM-Newton is sent to a complex set of algorithms and calibrations methods resulting in scientific data products elaborated and distributed by XMM-Newton Science Operations Centre. This work is marked in the last stage of data processing. The data treated in the project has been previously processed so the focus is kept on Machine Learning techniques. Although, as this work will be developed in an astronomical environment and cosupervised by ESA scientists, there is a strong astronomical point of view. El principal propósito de este trabajo es explorar los datos astronómicos recogidos por las cámaras EPIC del satélite XMM-Newton. Como resultado, dependiendo de la validación correspondiente, parte de las técnicas empleadas podrán ser implementadas en futuras versiones de la pipeline de procesamiento de los datos de XMM-Newton. XMM-Newton es un observatorio espacial de la Agencia Espacial Europea (ESA) que opera en el rango de los rayos X. Los datos recogidos por XMM-Newton son enviados a un complejo sistema de algoritmos y métodos de calibración que resultan en productos científicos elaborados y distribuidos por el Centro de Operaciones Científicas de XMM-Newton (XMM-Newton SOC). Este trabajo se enmarca en la última parte del procesamiento de los datos. Los datos tratados en este proyecto han sido previamente procesados para evitar desviar el foco de las propias técnicas de aprendizaje automático que se pretenden utilizar. L'objectiu principal d'aquest treball és explorar les dades astronòmiques recollides per les càmeres EPIC del satèl·lit XMM-Newton. Com a resultat, depenent de la validació corresponent, part de les tècniques utilitzades es poden implementar en futures versions del pipeline de processament de dades XMM-Newton. XMM-Newton és un observatori espacial de l'Agència Espacial Europea (ESA) que opera en el rang de raigs X. Les dades recollides per XMM-Newton s'envien a un complex sistema d'algoritmes i mètodes de calibratge que donen com a resultat productes científics desenvolupats i distribuïts pel XMM-Newton Scientific Operations Center (XMM-Newton SOC). Aquest treball forma part de l'última part del tractament de les dades. Les dades tractades en aquest projecte s'han processat prèviament per evitar desviar el focus de les tècniques d'aprenentatge automàtic que pretenen utilitzar.

This is thereproduction package for the A&A paper"The hot interstellar medium towards 4U 1820-30: a Bayesian analysis" by Rogantini et al. (2020). It contains data reduction scripts and aPython notebook for the characterization of the high-ionisation lines detected in the spectra of the low-mass X-ray binary 4U 1820-30. [Update in progress]

During their lifetime, galaxy clusters grow through the accretion of matter from the filaments of the large scale structure and from mergers with other clusters. These mergers release a large amount of energy into the intracluster medium (ICM) through merger shocks and turbulence. These phenomena are associated with the formation of radio sources known as radio relics and radio halos, respectively. Radio relics and halos are unique proxies to study the complex properties of these dynamically active regions of clusters and in general the micro physics of the ICM. Abell 3667 is a spectacular examples of a merging system hosting a large pair of radio relics. Due to its proximity (z=0.0553) and large mass, the system enables the study of these sources to a uniquely high level of detail. We observed Abell 3667 with MeerKAT as part of the MeerKAT Galaxy Cluster Legacy Survey. We used these data to study the large scale emission of the cluster, including its polarisation and spectral properties. We present the most detailed view of the radio relic system in Abell 3667 to date, with a resolution reaching 3 kpc. The relics are filled with a network of filaments with different spectral and polarisation properties that are likely associated with multiple regions of particle acceleration and local enhancements of the magnetic field. Conversely, the magnetic field in the space between filaments has strengths close to that expected in unperturbed regions at the same cluster-centric distance. Comparisons with MHD simulations supports the idea of filaments as multiple acceleration sites. Our observations also confirm the presence of an elongated radio halo, developed in the wake of the bullet-like sub-cluster that merged from the South-East. Finally, we associate the process of magnetic draping to a thin polarised radio source surrounding the remnant of the bullet's cool core., 28 pages, 30 figures, accepted A&A

We present results of temporal and spectral analyses on four XMM-Newton EPIC pn observations of IRAS 17020+4544, a narrow-line Seyfert 1 galaxy with evidence of a radio jet. Analysis of the light curves reveals that this radio-loud source does not behave like the bulk population of its radio-quiet counterparts. A trend of spectral hardening with increased flux is found. Variability is found to increase with energy, though it decreases as the spectrum hardens. The first 40 ks of the most recent observation behave uniquely among the epochs, exhibiting a softer spectral state than at any other time. Possible non-stationarity at low energies is found, with no such effect present at higher energies, suggesting at least two distinct spectral components. A reverberation signature is confirmed, with the lag-frequency, lag-energy, and covariance spectra changing significantly during the soft-state epoch. The temporal analysis suggests a variable power-law in the presence of a reflection component, thus motivating such a fit for the 0.3-10 keV EPIC pn spectra from all epochs. We find an acceptable spectral fit using the timing-motivated parameters and report the detection of a broad Fe K emission line, requiring an additional model component beyond the reflection spectrum. We discuss links between this source and other narrow-line Seyfert 1 sources that show evidence of jet activity, finding similarities among this currently very limited sample of interesting objects., Comment: Accepted for publication in MNRAS. 19 pages, 14 figures