High Resolution X-ray Spectroscopy of SN 1006

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High Resolution X-ray Spectroscopy of
SN 1006

Jacco Vink SRON National Institute for Space
Research The Netherlands
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Supernova Remnant Plasma Physics

• X-rays from SNRs are interesting for many
  reasons
• Studying the supernova phenomenon
• - nucleosynthesis (bulk mass visible in X-rays,
  alpha elements)
• - explosion energy and asymmetries
• Studying the interaction with the CSM/ISM
• Studying plasma/shock physics
• - high Mach number collisionless shocks
• - cosmic ray acceleration (prime sources up to
  1015 eV?)
• - influence of cosmic rays on plasma (energy
  drain)
• - physics of hot, thin plasmas
• Knowledge of plasma physics is a prerequisite
  for point 1

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Physics of SNR Plasmas
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Non-Equilibrium Ionization (NEI)
(oxygen)
Collision Ionization Equilibrium
He-like
NEI
SN 1006
Tycho
Cas A
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Temperature Non-equilibration
For strong shock, neglecting cosmic
ray sinks kTi 2(?-1)(?1)-2 mi vs2
3/16 mi vs2 (for ? 5/3)
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Why SN1006?

• young (1000 yr) and low density (0.1 ions/cc)
• ionization and equilibration scale with net
• for SN 1006 3 x 109 cm-3s
• cf Cas A net gt 1011 cm-3s
• (ionization and temperature equilibrium net gt
  1012 cm-3s)
• Optical/ UV spectroscopy indicates temperature
• non-equilibration
• (Laming et al. 1996 Ghavamian et al 2002)
• High Mach shock gt3000 km/s
• Interesting historical, supernova remnant

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SN 1006 some background

• SN 1006 aka G327.614.6 (NB high latitude!)
• bright (lt-6 mag) guest star in AD 1006
• recorded in Middle East, Asia Europe
• likely to be Type Ia (but lack of observed Fe)
• distance 2.1 kpc (Ghavamian et al. 2002,
  Winkler et al. 2002)
• 30 arcmin diameter
• Average velocity 9375 km/s
• Absorption column NH 7 x 1020 cm-2
• First shell remnant for which
• X-ray synchrotron emission was
• established (Koyama et al. 1995)

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XMM-Newton's Reflection Grating Specrometers
(RGS)
- Three telescopes - Two gratings - No slit,
spectral degradation ?? 0.124( ?f/1') Å
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Observational Strategy
Knot size lt 1 arcmin (0.4 arcmin FWHM)
Spectral resolution for bright lines e.g OVII
(22Å) gt 1/170
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RGS Spectrum
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Low charge state of neon
Ne Ka (RGS 2 order 1) measured centroid 13.78 /-
0.06 Å cf Ne IX w 13.44 Å, z 13.70
Å So not in Ne IX like state or unusually large
f/r ratio
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EPIC (CCD) spectra
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Constraining NEI
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The OVII Thermal Broadening
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OVII higher order lines
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The Spectrum of the Eastern RimHopeless for the
RGS or perhaps not?
Pointing
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The Shell Velocity of SN 1006
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O VII He-like triplet
Based on rates calculated by M. Gu
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Summary

• XMM's RGS allows high resolution spectroscopy of
  
• 1 arcmin sized objects, or larger if small
  details are present
• Many lines resolved that cannot be seen in
• CCD spectra, e.g. N VI,O VII n4,5,6 -gt n1
• No evidence for FeL lines, due to low ionization
• Plasma far out of ionization equilibration net
  2 x 109 cm-3s
• CCD/RGS spectra K line not always from He-like
• ionization state (Ne, Mg, Si), but due to inner
  shell processes
• Slow temp. equilibration of electrons and ions
  in NW
• kTe 1.5 keV and kTOVII 500 keV
• Evidence for 6000 km/s shell velocity in East

Results published in J. Vink, J.M. Laming, M.F.
Gu, A. Rasmussen, J. S. Kaastra Astrophysical
Journal Letters 587, L31 (2003)
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RGS Spectra
(Expected Fe XVII)