XMM-Newton : a pathfinder for future multi-wavelength and multi-messenger observations with Athena

Project Information

XMM2ATHENA

Grant agreement ID: 101004168

DOI

10.3030/101004168

Project closed

EC signature date 12 March 2021

Start date 1 April 2021

End date 30 September 2024

Funded under

• INDUSTRIAL LEADERSHIP - Leadership in enabling and industrial technologies – Space

Total cost

€ 1 999 723,75

EU contribution

€ 1 999 723,75

Coordinated by

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
France

Periodic Reporting for period 2 - XMM2ATHENA (XMM-Newton : a pathfinder for future multi-wavelength and multi-messenger observations with Athena)

Reporting period: 2022-04-01 to 2024-09-30

Summary of the context and overall objectives of the project

XMM-Newton is a European Space Agency (ESA) satellite that observes the Universe in the X-ray, ultra-violet and optical domains. It was launched over 25 years ago in December 1999. Over these last 25 years, the way astronomy is carried out has evolved and it is necessary to provide new software to allow astronomers to maximise the scientific return from the observatory and provide updated products using this software. This will enable astronomers that are not specialists in these wavelength domains to exploit the scientific output. After testing the new methods and software on current XMM-Newton data, we will further adapt the software for the future ESA mission, Athena, to be launched in the 2030s. Using X-ray observations is one of the best ways to find and study black holes, localise where hidden dark matter resides and witness the endpoints of massive stars as supernova explosions and their products, neutron stars, for example. Carrying out observations in these wavelengths helps us understand the Universe around us, test theories such as General Relativity, develop new technology and use this to teach and instruct students and the general public, improving our general understanding of nature.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

All of the deliverables have been made and all of the milestones achieved. We have successfully developed tools that allow us to cross-match many astronomical catalogues of sources and derive Spectral Energy Distributions (SEDs) that are distributed through several existing platforms as well as developing a new dedicated server to disseminate the results, https://xcatdb.unistra.fr/sedfinder/ . Using this data we were able to produce statistical identifications of sources and these results have been used to validate the work carried out. We have developed a new platform to determine the sensitivity limit or flux upper limit in case of no detection on any part of the sky observed with the X-ray cameras on XMM-Newton, http://flix.irap.omp.eu/ . Further this platform can take the stacked data in any particular region of the XMM-Newton observed sky and calculate an upper limit on the combined data. The algorithms and platform, along with some description about the XMM2ATHENA project have been described in a refereed publication. We have further developed the stacking algorithms to ensure that we reach the deepest fluxes possible when combining multiple exposures, see Figure 1 and we have developed new variability tasks that test all XMM-Newton X-ray sources for long-term variability over up to 35 years and look for short variability in sources that have not even been previously detected due to their faint nature. We have also generated a new module in the XMM-Newton automated pipeline to look for long-term variable sources in almost real time and provided a platform to retrieve the alerts to these variable sources, http://flix.irap.omp.eu/stonks for follow-up with other telescopes or to use in synergy with transients detected with other astronomical facilities. We have generated rudimentary spectra when none exist for a specific source and provide fits for these sources as well automatically generated spectra and use the various XMM2ATHENA products to carry out scientifically motivated fits. We provide all of the catalogues of these fits on the XMM2ATHENA webpage http://xmm-ssc.irap.omp.eu/xmm2athena/ available in English, French, Spanish and German. We provide classifications of the sources detected with the Optical Monitor telescope on board XMM-Newton and provide information about the variability of these sources. These catalogues are published on the XMM2ATHENA webpages, along with the classifications of the X-ray sources and the photometric redshifts that we have generated as a part of this project. To ensure excellent visibility of the tools and to validate the results, we have published studies made using the deliverables, with a total of 36 publications, all of which have open access. Much of the software has been built so that it can also be used for the next generation X-ray telescope, NewAthena. Finally, all of these tools and products were advertised during a 3 day workshop attended by more than 90 people in February 2024 : https://xmm2athena.sciencesconf.org/

During the project we have also released new incremental versions of the existing XMM-Newton X-ray catalogues, 4XMM-DR11(s), 4XMM-DR12(s), 4XMM-DR13(s) and 4XMM-DR14(s), as well as generating a catalogue constructed from all of the X-ray detections made during the slewing of the telescope, called XMMSL3. We have also hosted students for internships and had open days, as well as many other activities that can be seen on the XMM2ATHENA webpages and communicated through Facebook and X, to raise the profile of the project, the ESA observatories and X-ray data in general. Our project has enabled the number of papers being published with the XMM-Newton catalogues to increase three-fold and the total number of publications written worldwide per year to increase by 33%, compared to before the beginning of the project, see Figure 2.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

For the last 25 years, basic data reduction and analysis software has been available for the XMM-Newton satellite. This project has gone well beyond that, allowing XMM-Newton to be operated in a different manner to participate in Time Domain astronomy by issuing alerts for long term variable sources and scan the sky for very short and faint bursts that could be coming from gravitational wave events. Although the UV/optical telescope works in tandem with the EPIC X-ray cameras, the results from these domains have never been systematically exploited together until the developments made with XMM2ATHENA. We have produced artificial intelligence software and methods to classify all of the sources detected with the XMM-Newton satellite, allowing them to be identified statistically, but also sources from a range of other telescopes. In order to allow non-specialists to use these resources, we are providing all of the output in a single catalogue that can be accessed in many ways, including with the standard Virtual Observatory tools. We have carried out outreach activities to raise the profile of the work, the XMM-Newton and Athena observatories and X-ray data in general and we have devoted much of this effort to the younger generation and women. We have developed a citizen science project entitled CLAXSON that is available in five languages http://xmm-ssc.irap.omp.eu/claxson/index.php and we have promoted it through international events designed to raise the profile of STEM subjects for high school students.

The new tools we have provided will permit more scientists to exploit XMM-Newton data, and later that from Athena. Our project has allowed young scientists to be hired on temporary contracts, providing them with new skills in X-ray data analysis, so that they can become the major actors in the future mission Athena. We have also ensured that under-represented classes of astronomers have been hired in the project, with 5 out of 16 (31%) hires being female (where the average in Astronomy is ~25% and even less in high energy astrophysics) and 4/16 (25%) from non European/American countries.

Figure showing how stacking the data allows us to detect more sources

Papers/year using XMM-Newton data, 33% more/year (300% more using the catalogue - red) since project