March 11-13, 2002 Astro-E2 SWG 1 John P. Hughes Rutgers University Some Possible Astro-E2 Studies of Supernova Remnants

March 11-13, 2002Astro-E2 SWG2 Core Collapse SN Science I Cassiopeia A Chandra ACIS-S Nucleosynthesis: How abundant is Neon in the Cas A ejecta? With Chandra we see lots of Fe- and Si-rich ejecta, but it is hard to detect Ne in the CCD spectra – we need Astro-E2’s spectral resolution. Ne is an important diagnostic of explosive Ne burning. Also search for Na and Al. 3” x 4’ in diameter

March 11-13, 2002Astro-E2 SWG3 Core Collapse SN Science II G Chandra ACIS-S ~9’’ in diameter SNR contains: 135 ms pulsar; radio & X-ray pulsar wind nebula; O-, Ne-, & Mg-rich ejecta Dynamics: Optical O-rich ejecta show +/ km/s velocity range, but this material is only seen along the eastern edge. We need Astro-E2 to study the dynamics of the X-ray ejecta.

March 11-13, 2002Astro-E2 SWG4 Thermonuclear Supernovae Nucleosynthesis: Remnants of SN Ia’s are more spectrally uniform than core collapse SNe (note mostly grey/white color at left), making Astro-E2 spectra easier to interpret. Global abundances can help constrain models of burning-front propagation in SN Ia (Iwamoto et al 1999) Tycho’s SNR Chandra ACIS-S 9’ in diameter

March 11-13, 2002Astro-E2 SWG5 Thermonuclear Supernovae SN1006 shows nonthermal synchrotron emission (gray-blue color at left) from TeV electrons, as well as O, Ne, Mg, & Si emission from ejecta (red color at left). Astro-E2 can study the dynamics of the ejecta and nucleosynthesis (confirm presence of Fe). We should observe at various positions in the SNR (e.g., near center, part way out, near rim) for velocity studies and to see how the elemental species: O-group, Si- group, Fe-group are distributed. SN1006 NE Chandra ACIS-S Portion shown ~8’ square SNR ~ 35’ in diameter

March 11-13, 2002Astro-E2 SWG6 Trace element abundances W49B ASCA SIS spectrum SNR ~5.5’ x 4.5’ in diameter Confirm Chromium and Manganese in spectrum and search for odd-Z elements (e.g., Al, P, Cl, K) as a probe of SN type (Ia, II, …) and yields

March 11-13, 2002Astro-E2 SWG7 Shock Physics Measure post-shock electron temperature using line ratios as temperature diagnostics Measure post-shock electron temperature using line ratios as temperature diagnostics Best done behind Balmer-dominated shocks Best done behind Balmer-dominated shocks –Width of broad H  line gives post-shock proton temperature Determine degree of initial post-shock electron- ion temperature equilibration Determine degree of initial post-shock electron- ion temperature equilibration Issue: finding a good Galactic SNR for this Issue: finding a good Galactic SNR for this –Possibilities: Cygnus loop, RCW 86

March 11-13, 2002Astro-E2 SWG8 LMC SNRs: N49B N49B Chandra ACIS-S 2.6’ x 3.0” in diameter Central regions show enhanced Mg & Si; no enhanced O or Ne. Rim is “normal” LMC ISM. Enhanced Mg seen in global ASCA spectrum. Verify global abundances with Astro-E2, especially “normal” O and Ne.

March 11-13, 2002Astro-E2 SWG9 Ejecta in Old Galactic SNRs We are finding ejecta in more places and in older SNRs (based on Chandra studies of LMC SNRs). Known older Galactic SNRs with signs of ejecta include: Vela bullets Vela bullets Various places in the Cygnus Loop Various places in the Cygnus Loop These are good places to study the range of yields from SNe and probe the life cycle of matter. A related study: Is the presence of ejecta an explanation for center-filled SNRs (e.g., W44, W28)? A related study: Is the presence of ejecta an explanation for center-filled SNRs (e.g., W44, W28)? –Large angular diameter SNRs – good Astro-E2 targets