1. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The periastron and X-ray eclipse of WR25 (WN6ha+O) (the most massive star in the Galaxy) A.M.T. Pollock (ESA@ESAC) & M.F. Corcoran (NASA/USRA@GSFC) Swift XRT 2008 February ToO campaign progress report

2. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25  Car → ← HD 93129 HD 93250 → ← WR 25 The Carina nebula in X-rays

3. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 What’s so special about WR 25 ? Potsdam Wolf-Rayet IR-optical-UV models WR 25 M  ~110M 

4. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25  X-ray emission is bright  WR binaries >> single WR stars  collisionless plasma physics  chemical abundances (cf WR140)  X-ray absorption is significant  eclipses (cf WR140)  mass-loss rates  orbital geometry  source size  chemical abundances X-rays from colliding winds in Wolf-Rayet binaries WN6ha O a ~ 2AU WR 25

5. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 What XMM has done with WR 25

6. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 Gamen+’s double-lined orbit for WN6ha+O P = 207.85 ± 0.02 days e = 0.50 ± 0.02  = 215  ± 3 

7. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 X-ray absorption in WR25 WN6ha star

8. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The Swift campaign  Gamen+’s orbit  periastron passage on 2008 February 11  1  Swift ToO campaign  2008 January 25 to 2008 March 16  32 daily sequences  Two earlier archived observations of IGRJ10448-5945  Data analysis  xrtpipeline 0.11.6  Xspec v12 with the XMM EPIC-MOS point-source model   xspec> model constant(  )*wabs(  )*ISM*CWB(!  )   L X (  ) n X (  )

9. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The Swift XRT campaign Xspec analysis LXLX nXnX WR 25

10. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The Swift XRT campaign with WR25’s orbit WR O  WR O  O WR  LXLX nXnX WR 25

11. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The Swift XRT campaign compared with XMM 4 4 9910 10 10 9 9 L X with E-MOS  0.6(?) n X with E-MOS WR 25

12. European Space Astronomy Centre Villanueva de la Cañada, Madrid, Spain Andy Pollock XMM-Newton SOC The X-ray eclipse of WR25 The Swift XRT campaign conclusions  WR 25’s colliding winds and D, the binary separation  L X (D) increases smoothly to a maximum very near periastron  there follows a complex X-ray eclipse   (D)  rapid 30% occultation  R emission ~ R absorption ~ AU  watch this space for the orbital inclination   M(WN6ha) & M(O)  O  Of  WNE  WNL  WC Thanks to all at Swift; Alberto Moretti; and Aitor Ibarra. L X (WN6ha) is small