1. December 16, 2002SNoRe Cambridge, MA1 Modeling Ejecta in Supernova Remnant X-Ray Spectra John P. Hughes Rutgers University  Cara Rakowski, Rutgers  Jessica Warren, Rutgers  Dave Burrows, Penn State  John Nousek, Penn State  Peter Roming, Penn State  Parviz Ghavamian, Rutgers  Pat Slane, CfA  Sangwook Park, Penn State  Gordon Garmire, Penn State  Anne Decourchelle, Saclay

2. December 16, 2002SNoRe Cambridge, MA2 Where’s the Ejecta? Optical: SNRs with high velocity oxygen-rich features Optical: SNRs with high velocity oxygen-rich features Galactic: Cas A, G292.0+1.8, Puppis A Galactic: Cas A, G292.0+1.8, Puppis A LMC/SMC: N132D, E0540-69.3, E0102.2-72.2 LMC/SMC: N132D, E0540-69.3, E0102.2-72.2 Other: an unresolved SNR in NGC 4449 Other: an unresolved SNR in NGC 4449 Remnants of historical SNe Remnants of historical SNe e.g., SN1006, SN1572 (Tycho), SN1604 (Kepler) e.g., SN1006, SN1572 (Tycho), SN1604 (Kepler) Based on [Fe II] in absorption; X-ray spectra Based on [Fe II] in absorption; X-ray spectra Ejecta-dominated SNRs Ejecta-dominated SNRs e.g., W49B, G352.7-0.1, G337.2-0.7, G309.2-0.6 e.g., W49B, G352.7-0.1, G337.2-0.7, G309.2-0.6 Based on X-ray spectra (mostly ASCA) Based on X-ray spectra (mostly ASCA) Nearly all remnants up to ages of at least ~10,000 yrs!!! Nearly all remnants up to ages of at least ~10,000 yrs!!! N49, N63A, DEM71, N49B, and E0103-72.6 N49, N63A, DEM71, N49B, and E0103-72.6 Based on Chandra spectro-imaging Based on Chandra spectro-imaging

3. December 16, 2002SNoRe Cambridge, MA3 Thermonuclear Supernovae SN Ia (Hoyle & Fowler 1960) SN Ia (Hoyle & Fowler 1960) –No hydrogen, a solar mass of 56 Ni, some intermediate mass elements (O, Mg, Si, S,…) –Subsonic burning (deflagration) of approx. one Chandrasekhar mass of degenerate C/O –C-O white dwarf accreting H/He-rich gas from a companion –No compact remnant –Mean rate ~ 0.3 SNU

4. December 16, 2002SNoRe Cambridge, MA4 SN Ia Integrated Yields Iwamoto et al, 1999, ApJS, 125, 439

5. December 16, 2002SNoRe Cambridge, MA5 SN Ia Yields vs. Radius Iwamoto et al, 1999, ApJS, 125, 439 Mass (M sun ) O 0.056-0.143 Ne 0.0008-0.0045 Mg 0.027-0.0158 Si 0.142-0.279 Fe 0.648-0.834

6. December 16, 2002SNoRe Cambridge, MA6 Core Collapse Supernovae SN II, SN Ib/c (Zwicky & Baade 1934) SN II, SN Ib/c (Zwicky & Baade 1934) –Massive stars that explode with (SN II) or w/out (SN Ib/c) their H envelopes –Photodisintegration of Fe, plus electron capture on nuclei, remove central P support –Core collapses, leading to NS or BH –Core stiffens, rebounds and drives an outward moving shock –Neutrinos or jets needed to produce explosion –Mean Rate ~ 1.3 SNU

7. December 16, 2002SNoRe Cambridge, MA7 Nucleosynthesis in CC SNe Hydrostatic nucleosynthesis Hydrostatic nucleosynthesis –During hydrostatic evolution of star –Builds up shells rich in H, He, C, O, and Si –Amount of C, O, Ne, Mg ejected varies strongly with progenitor mass Explosive nucleosynthesis Explosive nucleosynthesis –Some mechanism drives a shock wave with 10 51 + erg through the Fe-core –Burning front T’s of ~10 9 K cause explosive O- and Si- burning –Only affects the central parts of the star – outer layers retain their pre-SN composition

8. December 16, 2002SNoRe Cambridge, MA8 Explosive Nucleosynthesis Process T (10 9 K) Main Products Explosive complete Si-burning 5.0 “Fe”, He Explosive incomplete Si-burning 4.0 Si, S, Fe, Ar, Ca Explosive O-burning 3.3 O, Si, S, Ar, Ca Explosive Ne/C-burning 1.2 O, Mg, Si, Ne

9. December 16, 2002SNoRe Cambridge, MA9 Typical Mass Fractions Element Ex Ne Ex O Ex Si-i Ex Si-c O0.720.45 Ne0.13 Mg0.090.005 Si0.020.300.40 S0.200.25 Ar0.0250.06 Ca0.020.05 Fe0.200.70

10. December 16, 2002SNoRe Cambridge, MA10 Major Yields (in Solar Masses) Element 13 M o 15 M o 20 M o 25 M o C0.0600.0830.1150.148 O0.2180.4331.4803.00 Ne0.0280.0390.2570.631 Mg0.0120.0460.1820.219 Si0.0470.0710.0950.116 S0.0260.0230.0250.040 Ar0.00550.00400.00450.0072 Ca0.00530.00330.00370.0062 Fe*0.150**0.130*0.075*0.050*

11. December 16, 2002SNoRe Cambridge, MA11 SN II Yields vs. Radius Thielemann, Nomoto, and Hashimoto, 1996, ApJ, 460, 408 20 M sun model Hydrostatic nucl. M>2.05 Explosive nucl. ~1.6 <M<2.05 Mass cut set so 0.075 M sun of Fe is ejected

12. December 16, 2002SNoRe Cambridge, MA12 Uncertainties Thermonuclear SNe Thermonuclear SNe –Physics of flame front propagation –Precise progenitor system unknown – rate of accretion and composition unknown Core Collapse SNe Core Collapse SNe –Explosion mechanism unknown –Location of mass cut (compact object/ejecta) –Convection during He-burning – 12 C(  ) 16 O reaction rate

13. December 16, 2002SNoRe Cambridge, MA13 Useful General References Trimble 1982, Rev Mod Phy, 54, 1183 (Supernovae Part I) Trimble 1982, Rev Mod Phy, 54, 1183 (Supernovae Part I) Trimble 1983, Rev Mod Phy, 55, 511 (Supernovae Part II) Trimble 1983, Rev Mod Phy, 55, 511 (Supernovae Part II) Bethe 1990, Rev Mod Phy, 62, 801 (Supernova Mechanisms) Bethe 1990, Rev Mod Phy, 62, 801 (Supernova Mechanisms) Arnett 1996, “Supernovae and Nucleosynthesis” (Princeton University Press: Princeton) Arnett 1996, “Supernovae and Nucleosynthesis” (Princeton University Press: Princeton) Wallerstein et al, 1997 Rev Mod Phy, 69, 995 (update of B 2 FH) Wallerstein et al, 1997 Rev Mod Phy, 69, 995 (update of B 2 FH)

14. December 16, 2002SNoRe Cambridge, MA14 X-ray Emission/Atomic Processes Continuum emission – thermal bremsstrahlung: Line emission: Abundance of element Z Ionization fraction of ion i

15. December 16, 2002SNoRe Cambridge, MA15 Abundance Determination Issues Thermodynamic State Thermodynamic State –Nonequilibrium Ionization (n e t~10 5 cm -3 yr) –T, n evolution with time/radius (e.g., Sedov) –Other effects:  Heating/cooling in pure element ejecta  T e /T p  Nonthermal particle (rates and excitation) –Absolute abundances (e.g., Si/H, O/H, Fe/H)  Rely on assumption of H/He-dominated continuum –Relative abundances (e.g., Mg/Si, O/Fe)  OK, if species have the same spatial distribution

16. December 16, 2002SNoRe Cambridge, MA16 Ejecta Mass Determination Issues Volume estimation Volume estimation Clumping (reduces actual mass) Clumping (reduces actual mass) Distance (M~D 5/2 ) Distance (M~D 5/2 ) Source of electrons Source of electrons –Measure EM = n e n I V –Solar abundance: n e ~ n H ~ n Fe /10 7.6-12 ~ 25000n Fe –Pure Fe: n e ~ 20n Fe –Inferred M pure Fe /M solar ~ 35

17. December 16, 2002SNoRe Cambridge, MA17 Overturning Our View of Cas A Hughes, Rakowski, Burrows, and Slane 2000, ApJL, 528, L109.

18. December 16, 2002SNoRe Cambridge, MA18 Oxygen-Rich SNR G292.0+1.8 Park et al 2001, ApJL, 564, L39

19. December 16, 2002SNoRe Cambridge, MA19 Oxygen-Rich SNR G292.0+1.8 Ejecta Rich in O, Ne, and Mg, some Si [O]/[Ne] < 1 No Si-rich or Fe-rich ejecta

20. December 16, 2002SNoRe Cambridge, MA20 Oxygen-Rich SNR G292.0+1.8 Normal Composition, CSM Central bright bar – an axisymmetric stellar wind (Blondin et al, 1996) Thin, circumferential filaments enclose ejecta-dominated material – red/blue supergiant winbd boundary

21. December 16, 2002SNoRe Cambridge, MA21 Oxygen-Rich SNR G292.0+1.8 Point source Featureless power-law spectrum, photon index = 1.7 Surrounded by diffuse X-ray/radio nebula Off center, implied speed of ~800 km/s

22. December 16, 2002SNoRe Cambridge, MA22 PSR J1124-5916 in G292.0+1.8 Discovered at Parkes (Camilo et al 2002) Discovered at Parkes (Camilo et al 2002) P=0.1353140749 s, dP/dt=7.471E-13 P=0.1353140749 s, dP/dt=7.471E-13 Characteristic age ~ 2900 yrs (SNR age ~ 1600 yrs) Characteristic age ~ 2900 yrs (SNR age ~ 1600 yrs) Not detected in coherent FFT of Chandra HRC observation Not detected in coherent FFT of Chandra HRC observation 3.5 sigma detection from Z n 2 test at radio parameters 3.5 sigma detection from Z n 2 test at radio parameters Only ~130 pulsed events in 50 ks Only ~130 pulsed events in 50 ks

23. December 16, 2002SNoRe Cambridge, MA23 PSR J1124-5916 Image Analysis: point source and elliptical gaussian (small nebula) Image Analysis: point source and elliptical gaussian (small nebula) Point source contains ~160 X-ray events Point source contains ~160 X-ray events Pulsed fraction high ~80% Pulsed fraction high ~80% Unpulsed point source emission < 1.4E-3 cts/s Unpulsed point source emission < 1.4E-3 cts/s L BB < 10 33 erg/s L BB < 10 33 erg/s Below standard cooling curve for 2000 yr old PSR

24. December 16, 2002SNoRe Cambridge, MA24 DEM L71: Ejecta and Shock Physics H alpha Soft X-ray Hughes, Ghavamian, Rakowski, and Slane, ApJL, 582, in press (10 Jan 2003) Rutgers Fabry-Perot/NOAO Chandra/NASA Hard X-ray

25. December 16, 2002SNoRe Cambridge, MA25 Fe-Rich Ejecta

26. December 16, 2002SNoRe Cambridge, MA26 Properties of DEM L71 Ejecta Outer rim: lowered abundances, ~0.2 solar (LMC ISM) Outer rim: lowered abundances, ~0.2 solar (LMC ISM) Core: enhanced Fe abundance, [Fe]/[O] > 5 times solar (ejecta) Core: enhanced Fe abundance, [Fe]/[O] > 5 times solar (ejecta) Thick elliptical shell, 32” by 40” across (3.9 pc by 4.8 pc) Thick elliptical shell, 32” by 40” across (3.9 pc by 4.8 pc) Dynamical mass estimate Dynamical mass estimate r’ ~ 3.0 M ej = 1.1 M ch (n/0.5 cm -3 ) Wang & Chevalier 2001 EM mass estimate EM mass estimate EM ~ n e n Fe V M Fe < 2 M sun Main error: source of electrons Main error: source of electrons Fe-rich, low mass SN Ia

27. December 16, 2002SNoRe Cambridge, MA27 DEM L71: Shock Physics Nonradiative Balmer-dominated shock Measure post-shock proton temperature X-ray emission from thermal bremsstralung Measure post-shock electron temperature

28. December 16, 2002SNoRe Cambridge, MA28 Nonradiative Balmer Shocks Nonradiative means that a radiative (cooling) zone does not form Nonradiative means that a radiative (cooling) zone does not form Low density (partially neutral) gas Low density (partially neutral) gas High velocity shocks High velocity shocks Narrow component: cold H I overrun by shock, collisionally excited Narrow component: cold H I overrun by shock, collisionally excited Broad component: hot postshock protons that charge exchange with cold H I Broad component: hot postshock protons that charge exchange with cold H I Ghavamian, Rakowski, Hughes, and Williams 2002, ApJ, submitted. Width of broad component yields post shock proton temperature (Chevalier & Raymond 1978; Chevalier, Kirshner, & Raymond 1980)

29. December 16, 2002SNoRe Cambridge, MA29 Constraining the Electron Temperature Fit NEI shock models to 3 spatial zones to follow evolution of T e Fit NEI shock models to 3 spatial zones to follow evolution of T e Study 5 azimuthal regions with sufficient Chandra statistics and broad Halpha component Study 5 azimuthal regions with sufficient Chandra statistics and broad Halpha component Available data cannot constrain T e gradients Available data cannot constrain T e gradients Rakowski, Ghavamian, Hughes, & Williams 2002, ApJ, submitted. Data do determine mean T e Suggest partial to compete temperature equilibration

30. December 16, 2002SNoRe Cambridge, MA30 Results on T e /T p from DEM L71 Shows trend for higher equilibration for lower speed shocks Shows trend for higher equilibration for lower speed shocks X-ray/Halpha results consistent with other purely Halpha ones X-ray/Halpha results consistent with other purely Halpha ones

31. December 16, 2002SNoRe Cambridge, MA31 N63A Middle-aged SNR Middle-aged SNR –34” (8.2 pc) in radius –2000-5000 yrs old –2 nd brightest LMC SNR “Crescent”-shaped features “Crescent”-shaped features –Similar to features in Vela –Clumps of high speed ejecta –Not ejecta dominated Triangular hole Triangular hole –X-ray absorption –Approx. 450 solar mass cloud –On near side No PSR or PWN No PSR or PWN – L X < 4x10 34 erg s -1 Warren, Hughes, & Slane, ApJ, in press (20 Jan 2003)

32. December 16, 2002SNoRe Cambridge, MA32 N49B Middle-aged SNR Middle-aged SNR –80” (19 pc) in radius –5000-10,000 yrs old –Near N49 Bright and faint rims Bright and faint rims –LMC composition –Varying ISM density No PSR or PWN No PSR or PWN – L X < 3x10 34 erg s -1 Magnesium-rich ejecta Magnesium-rich ejecta –Equivalent-width maps –No O or Ne enhancement Park, Hughes, Slane, et al. ApJ, in prep.

33. December 16, 2002SNoRe Cambridge, MA33 SNR 0103-72.6 Middle-aged SNR Middle-aged SNR –87” (25 pc) in radius –>10,000 yrs old (??) –2 nd brightest SMC SNR No PSR or PWN No PSR or PWN – L X < 4x10 34 erg s -1 Circular outer shock Circular outer shock –Low SMC-type abundances –Why so circular? Central excess Central excess – Apparently O, Ne, Mg rich ejecta Park, Hughes, et al., ApJ, in prep.

34. December 16, 2002SNoRe Cambridge, MA34 THE END