1 / 24

Comparing X-ray Catalogues for Supersoft Sources in M31

Explore comparisons of XMM-Newton Deep Survey with ROSAT and Chandra catalogues to identify Supersoft sources in M31. Learn about the methodology, results, and classification methods of X-ray sources.

blam
Download Presentation

Comparing X-ray Catalogues for Supersoft Sources in M31

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Supersoft sources in M 31: Comparing the XMM-Newton Deep Survey, ROSAT and Chandra catalogues Holger Stiele SuperSoft X-ray Sources – New Developments ESAC Madrid 20.05.2009

  2. The Large Program Collaboration 19 scientists from 7 countries • PI: W.Pietsch (MPE) • MPE: V. Burwitz, M. Freyberg, J. Greiner, F. Haberl, H. Stiele • And: R. Barnard (The Open University), D. Hatzidimitriou (University of Crete), M. Hernanz (CSIC-IEEC), G. Israel (INAF), U. Kolb (The Open University), A. Kong (National Tsing Hua University), P. Plucinsky (Harvard-Smithsonian Centre for Astrophysics), P. Reig (IESL), G. Sala (UPC/IEEC), M. Sasaki (Harvard-Smithsonian Centre for Astrophysics), L. Shaw Greening (The Open University), L. Stella (INAF), B. Williams (Pennsylvania State University) Holger Stiele

  3. Outline • The XMM-Newton Deep Survey catalogue • Supersoft sources  optical novae • Comparing the XMM-Newton Deep Survey, ROSAT and Chandra catalogues • The catalogues • The method • The results Holger Stiele

  4. Image • of Deep survey (“outer ring”) and archival (“major axis”) data (see Pietsch et al. 2005) • Fields with high background repeated • Optical extent indicated by D25 ellipse 0.2 – 1 keV1 – 2 keV2 – 12 keV SSSs; fgstars +SNRs;hard (AGNs,XRBs,CrablikeSNR) Extended sources  mostly background galaxy clusters Holger Stiele

  5. Hardness Ratios SSS HR2 versus HR1  separate SSS; thermal SNRs and fg stars = X-ray colour i= 1…4 B1: 0.2-0.5 keVB2: 0.5-1.0 keVB3: 1.0-2.0 keVB4: 2.0-4.5 keVB5: 4.5- 12 keV • fg star+ AGNGal/GlC  XRB SSS SNR Further classification methods: • Extent • Time variability • Cross correlations with optical and radio source catalogues Holger Stiele

  6. X-ray Sources in M 31 Field: Identification and Classification +  1951 • SSS 43 identified classified • SSS 43 • SNR 25 38 • Globular clusters 36 17 • XRB 10 22 • foreground stars 22 243 • AGN 3 49 • Galaxies 4 21 • Galaxy clusters 1 1 • Hard 1289 • Without 127 Holger Stiele

  7. Supersoft Sources • Definition: • Radiation with effective temperature of 10 to 100 eV • Luminosities: ~1036-39 erg s-1 • HR1 < 0 and HR2 - EHR2 < -0.96 or HR2 not defined, HR3, HR4 not defined • 43 SSSs, 27 “new” Holger Stiele

  8. Flux Distribution Blackbody “model” withTbb = 50 eVNH = 6.61020 cm-2 Unabs. fluxes Novae Period 217sTrudolyubov & Priedhorsky 2008 Number of sources M31N2001-11a M31N2005-01c erg cm-2 s-1 M31N2007-06b Period 865.5s (Nova?) Osborne et al. 2001 7.3  1036 erg/s Holger Stiele

  9. Optical Novae 1997-10c 2005-01c 1997-10c 2007-06b 2005-01b 2005-09b • Major class of SSSs in centre of M 31: optical novae(Pietsch et al. 2005, 2007) • Outer regions: not deep enough optical and no X-ray monitoring for novae/SSSs  only snapshots (X-rays) only random detections  difficult to determine general properties of disk nova population SSSsNovae Holger Stiele

  10. Optical Novae (II)  35 5.4 1038 Holger Stiele

  11. XMM-Newton Deep Survey • 1951 sources • 43 Supersoft sources Comparing the XMM-Newton Deep Survey, ROSAT and Chandra catalogues Holger Stiele

  12. ROSAT PSPC Survey • PSPC survey covering the entire galaxy twice 560 X-ray sources Supper et al. 1997, 2001 • Supersoft sources selected fromGreiner 2000and Kahabka 1999: • Similar selection criterion (as used for XMM-Newton) • Two hardness ratios (based on standard ROSAT energy bands) • band separation energies at ~ 0.5 keV, and ~ 1 keV • ROSAT observations taken about > 10 yr earlier than XMM-Newton observations ( investigation of long term variability) Holger Stiele

  13. Chandra Observations Voss & Gilfanov 2007 • Observation of selected fields, especially central region Kong et al. 2002, Kaaret 2002, Di Stefano et al. 2004, Williams et al. 2004, 2006, • Very soft sources Di Stefano et al. 2004 • Three energy bands: S: 0.1-1.1 keV; M: 1.1-2 keV; H: 2-7 keV • Several criteria to select SSSs and QSSs • Important difference: • Contamination of SSS class with • Temporal distance to XMM- Only one band below ~1 keV foregroundstars, SNRs and soft AGNs Newton observations:centre and Field 2: < 1 yrFields 1+3: > ~ 4yr Image: Di Stefano et al. 2004 Holger Stiele

  14. Method Two step process: First step: Were the XMM-Newton SSSs detected in previous surveys? Full ROSAT PSPC XMM – Newton SSS Full Chandra Second step: How many ROSAT/Chandra SSSs are detected with XMM-Newton? ROSAT SSS Full XMM Deep Survey Chandra VSS Holger Stiele

  15. XMM-Newton SSS to ROSAT PSPC Surveys • 43 XMM-Newton SSS, 12 brighter than ROSAT detection threshold (~5.310-15 erg cm-2 s-1): • 2 also found as ROSAT SSSs • 10 not detected with ROSAT: 6 recent novae, 1 transient, 1 variable  2 must be transient/highly variable • 31XMM-Newton SSS with fluxes below ROSAT detection threshold: • 1also found as ROSAT SSSs (~factor 22-25 brighter in ROSAT observations) • 3 chance coincidences • 27 remaining sources: 7 recent novae, 1 transient (Di Stefano et al. 2004) Holger Stiele

  16. XMM-Newton SSS to Chandra Surveys • 9 XMM-Newton SSSs have Chandra counterparts: • 6 are also classified as SSSs from Chandra • 8 of the 9 sources are located in the centre of M 31 • 34 sources do not have Chandra counterparts: • 7 are in regions not covered with Chandra • 10 are novae (4 after 2005, 6 no Chandra detections (see Pietsch et al. 2005, 2007 and M31N1999-10c, M31N2001-11a)) • 1 variable Holger Stiele

  17. ROSAT SSSs to XMM-Newton Deep Survey • 34 ROSAT SSS, 4 not in observed XMM-Newton field • 14 correlations with XMM-Newton sources • 16 ROSAT SSS without XMM-Newton counterparts: 1 nova Where are the novae?No systematic search/monitoring campaign in the years before 1990  number of known optical novae very low (see talk of W. Pietsch) most of these sources not highly variable (fvar < 5) Holger Stiele

  18. Chandra VSSs to XMM-Newton Deep Survey • 20 Chandra SSSs • 15 correlations with XMM-Newton sources: • 5 not detected with XMM-Newton (4 transients (Di Stefano et al. 2004, 2 of them novae),1 faint) Holger Stiele

  19. Chandra VSSs to XMM-Newton Deep Survey • 23 Chandra QSSs • 12 correlations with XMM-Newton sources: • 11 not detected with XMM-Newton (1 outside XMM field, 5 transients (Di Stefano et al. 2004), 1 in crowded centre, 2 faint) Holger Stiele

  20. What do we learn? • Two are located in the central field: • XMMM31 J004318.8+412017 = r3-8 = [SHL2001] 235: foreground polar? (Williams et al. 2006) • XMMM31 J004252.5+411540 = r2-12 = [SHL2001] 203 = [PFJ93] 58 = [TF91] 69: 217s period (Trudolyubov et al. 2008) • XMMM31 J003840.5+401956 = s2-26 = [SHL2001] 27: • 3 sources detected in all 3 missions  visible for more than a decade: r3-8 r2-12 ROSAT • ROSAT: ~22-25  brighterXMM: June 2006 – Jan. 2008 • in 3 Chandra observations (2000-2001) only once visible  variable(Di Stefano et al. 2004) s2-26 XMM-Newton Chandra Holger Stiele

  21. What do we learn? (II) • Of 12 XMM-Newton sources with brightness above ROSAT threshold, only 2 observed by ROSAT  underlines variability of the source class on long time scales (~83% variable, cf. Greiner et al. 2004) • ROSAT as well as Chandra SSSs contain sources of other classes Holger Stiele

  22. What do we learn? (III) • Two interesting sources: • XMMM31 J004307.1+411810 = r3-115:Chandra and XMM-Newton observations between 2000-end 2001: SSSXMM-Newton observation Jan. 2002: hard spectrum (Pietsch et al. 2005) • XMMM31 J004247.9+411549 = r1-25:Chandra observations between 2000-end 2001: SSSXMM-Newton observation July 2004: hard spectrumoptical counterpart within 1.2” (‘regular or semi-regular red variable’ Fliri et al. 2006) • Nature unclear: X-ray transient (BH primary) or symbiotic r3-115 r1-25 Holger Stiele

  23. Summary • Deep XMM-Newton survey of M 31  1951 X-ray sources, 43 Supersoft sources • Optical novae are an important class of SSSs in M 31 (5 in addition to Pietsch et al. 2005, 2007) • Correlation with ROSAT PSPC surveys and Chandra catalogues • 3 persistent SSSs • SSSs are a highly variable source class • Many ROSAT and Chandra SSSs get other classes from XMM-Newton observations • Two sources that show supersoft-hard transition between Chandra and XMM-Newton observations Holger Stiele

  24. Thank you for your attention The large program collaboration: • PI: W.Pietsch (MPE) • MPE: V. Burwitz, M. Freyberg, J. Greiner, F. Haberl, H. Stiele • And: R. Barnard (The Open University), D. Hatzidimitriou (University of Crete), M. Hernanz (CSIC-IEEC), G. Israel (INAF), U. Kolb (The Open University), A. Kong (National Tsing Hua University), P. Plucinsky (Harvard-Smithsonian Centre for Astrophysics), P. Reig (IESL), G. Sala (UPC/IEEC), M. Sasaki (Harvard-Smithsonian Centre for Astrophysics), L. Shaw Greening (The Open University), L. Stella (INAF), B. Williams (Pennsylvania State University) Holger Stiele

More Related