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XMM-Newton contribution

XMM-Newton contribution. 1E1207-52. EPIC 230 ksec. 1 st direct measurent of the magnetic field of an isolated neutron star (where cyclotron absorption is taking place ). 2.1 keV. 2.8 keV. 1.4 keV. 0.7 keV. Conclusions. For electrons: <B> 8 10 10 G

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XMM-Newton contribution

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  1. XMM-Newton contribution

  2. 1E1207-52 EPIC 230 ksec

  3. 1 st direct measurent of the magnetic field of an isolated neutron star (where cyclotron absorption is taking place) 2.1 keV 2.8 keV 1.4 keV 0.7 keV

  4. Conclusions For electrons: <B> 8 1010 G for protons : <B> 1.6 1014 G PROBLEM pdot:(1.4 ± 0.3) 10-14 s/s implies B= 2-3 1012 but also an age of 5 105 y versus the SN age ( circa 104 ys)

  5. Geminga MOS EPIC 100 ksec

  6. Energetics Edot 3 1034 erg/sec D = 160 pc m=170 mas/y vtr =120 km/sec Geminga luminosity 3 1031 erg/sec (0.1-5 keV) Tails luminosity 6.8 1028 erg/sec The tails account for 2 10-6 Edot

  7. VNS=mD/cos(i)

  8. from bow-shock VNS=mD/cos(i) we can obtain 0.06 < rISM < 0.15 at/cm-3 which implies 7 < M < 20

  9. What produces the X-rays Power law spectrum -> synchrotron radiation -> need for electrons and magnetic field

  10. From bow-shock theory rshock = 4 rISM Since B is frozen-in Bshock = 4 BISM Bshock = 10-5 G

  11. To produce keV photons in 10-5 G B field one needs 1014 eV electrons

  12. 1014 eV electrons will have a Larmor radius of 3.4 1016 cm  thickness 6.8 1016 cm 27” Caraveo et al. 2003 Science 301, 1345 1014 eV electrons will lose half of their energy in 800 y . 180 “ / 170 mas/y = 1,000 y

  13. Time-averaged spectroscopy Pn data ~ 53,000 photons

  14. Timing analysis Gamma peaks Common minimum

  15. Phase-resolved spectroscopy

  16. Phase-resolved spectroscopy Caraveo et al, 2004 Science 305,376

  17. Phase-resolved emission (160 pc)

  18. Conclusions • hot spot ( ~1.9 M °K), radius 0-60 m • Probably polar cap seen at 70°-80° inclination • cosq x R (RW/c)1/2 (~300m) • luminosity 1.5 1029 erg/sec rotating • -Cool black-body ( ~.48 M °K), Eurasia size luminosity 2.6 1031 erg/sec • Power law photon index 1.7 ± 0.1 luminosity 7.7 1029 erg/sec

  19. Is Geminga unique?

  20. EPIC view of PSRs B1055 & B0656 1055-52 MOS 83 ksec 0656+14 MOS 40 ksec pn 60 ksec 85,000 photons pn 35 ksec 120,000 photons

  21. Phase-averaged spectra

  22. Geminga They all show phase spectral variations 0656 1055

  23. 1055-58 Cool bb: is it the surface of the NS? Geminga 0656+14 0656  problem

  24. 1055-58 Hot bb: Geminga rotator inclinations? 0656+14 0656 hot spot(s) sizes?

  25. Hot bb: heated polar cap(s) ? their dimensions are vastly different although they should not !!! theoretical cap radii ~250-320 m real EPIC radii: 60, 800, 1500 m

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