THE XMM-NEWTON SPECTRAL DATABASE I. GEORGANTOPOULOS A. CORRAL - - PowerPoint PPT Presentation

THE XMM-NEWTON SPECTRAL DATABASE

• I. GEORGANTOPOULOS
• A. CORRAL

NATIONAL OBSERVATORY OF ATHENS

OUTLINE OF THE TALK

• Introduce ourselves
• X-ray Astronomy
• ESA’s XMM mission
• The largest catalogue of X-ray sources ever (3XMM)
• Maximising the XMM source catalogue:

Prodex project A: 2012-2014 The XMM spectral catalogue Prodex project B: 2016-2018 The photometric redshifts THE FUTURE ATHENA

INTRODUCING OUR GROUP

• X-ray Astronomy group / IAASARS Institute / National Observatory of

Athens

• National Observatory is the oldest research Centre in Greece (1842)
• Consists of 3 Institutes, IAASARS being the largest
• X-ray Astronomy Group -2 permanent members of staff - 1 scientific

research staff, 2 postdocs 2 research students -

• working primarily with XMM-Newton (ESA) but also with other missions

such as NASA’s Chandra and SWIFT.

• We try to maintain our group the forefront of research (Active Galactic

Nuclei) introducing novel techniques in data analysis (e.g. Bayesian methods)

WE PARTICIPATE IN SOFTWARE DEVELOPMENT FOR THE GERMAN/RUSSIAN MISSION EROSITA, TWO PRODEX PROJECTS FOR XMM, AND WE ARE PART OF ESA’S ATHENA GROUND SEGMENT

X-RAY ASTRONOMY & ESA

• X-ray astronomy is at the heart of ESA’s core program

(astrophysics/space sciences):

• EXOSAT, XMM and in several years ATHENA (notice ESA’s X-ray

programme growing fast and outpacing the US over the years)

• what is all about and why do we care to spend almost 1bn ?
• The X-rays observe the hot and energetic Universe invisible in
• ther wavelengths

X-RAY ASTRONOMY WHAT IS IT ?

• The higher the temperature of a body,

the higher the energy of the emission

MOST OFTEN THIS ULTRA-HOT MATERIAL IS FOUND AROUND BLACK HOLES (BH) AT THE CENTRES OF GALAXIES (ACTIVE GALACTIC NUCLEI OR AGN) X-RAY ARE PRODUCED BY PLASMA WITH A TEMPERATURE OF MILLION DEGREES XMM/CDFS

ESA’S XMM-NEWTON MISSION

• Launched 16 years ago and still performing

perfectly well

• XMM enjoys a huge success with over 4500

research papers and a vast number of citations

• Carrying 3 X-ray telescopes which are the

largest ever (they can accumulate a large amount of photons):

• producing sharp images and at the same time

X-ray spectra

• these spectra are the subject of our prodex

projects

X-RAY SPECTRA

SPECTRUM OF AN ACTIVE GALACTIC NUCLEUS (AGN) BLACK IS THE OBSERVED WE CAN DECOMPOSE THE DIFFERENT PHYSICAL COMPONENTS AND REVEAL THE STRUCTURE OF THE MATTER NEAR THE BLACK HOLE

THROUGH THIS SPECTRUM ‘MAGIC’ WE CAN RECONSTRUCT THE REGION AROUND THE BLACK HOLE SPECTRUM

THE XMM LEGACY: THE XMM SOURCE CATALOGUE

XMM OBSERVATIONS ARE PROPRIETARY FOR 12 MONTHS. THEN THEY BECOME PUBLIC. THE XMM CATALOG EXPLOITS THESE OBSERVATIONS FOR SERENDIPITOUS SOURCES

THE 3XMM CATALOGUE

4% of the sky and still growing

1750 sq. degrees 700,000 sources

(median flux 2.4x10-14 cgs 0.5-2 keV)

EXPONENTIAL GROWTH OF OUR KNOWLEDGE OF THE X-RAY UNIVERSE

PRE-1970 I.E. THE UHURU MISSION 30 X-RAY SOURCES UHURU MISSION 340 X-RAY SOURCES OVER THE WHOLE SKY XMM 700,000 SOURCES

OUR PRODEX. THE SPECTRAL CATALOG

• 120,000 sources had enough counts to produce an X-ray spectrum.
• All these have been automatically analysed
• using PERL scripts and the XSPEC spectral fit public software
• in a very intensive computational effort (running for many weeks in an 8-processor

cluster).

• This is a major tool for the astronomical community both non X-ray astronomers

and X-ray astronomers alike.

• The analysis of X-ray spectra is very demanding impeding astronomers of other

wavelengths to easily do it

• Even for X-ray astronomers, experienced in the analysis, the database that can be

searched for a specific type of source is extremely powerful tool.

THIS PRODEX PROJECT PROVIDES ADDITIONAL IMPACT TO THE XMM CATALOG FOR YEARS TO COME

THE CURRENT PRODEX PROJECT

• need to have the distances of the (extragalactic) sources in order

to enhance the impact of the 3XMM catalog.

• This will be done with the use of photometric redshifts. these

methods use optical photometry to derive the source’s redshift.

• Machine learning techniques are used
• The current project will be based on the work performed by the

EU FP7 Arches project (found optical counterparts for all 3XMM sources)

THE PRODUCTS

• The catalog is available in the NOA website in Greece and also in

the searchable X-ray Astronomy database LEDAS in Leicester

• Refereed Publications in the international

Astronomy&Astrophysics journal fully explaining the catalogue and provide example scientific results

• The software has been handed to the XMM Survey Science Centre

so that new sources are analysed as long as XMM operates.

THE FUTURE: ESA’S ATHENA MISSION

launch 2028. The largest X-ray mission ever. It will consolidate Europe’s as the leader in X-ray Astronomy

THE IAASARS/NOA AND CRETE ARE AMONG THE FEW INSTITUTES IN EUROPE THAT IS ALREPARTICIPATING IN ATHENA’S GROUND SEGMENT (THE CONSTRUCTION OF THE SOFTWARE FOR THE PIPELINE AND DATA ANALYSIS)

PRODEX WILL EXPAND AND SUPPORT OUR ROLE IN THIS EXTREMELY IMPORTANT SPACE PROJECT