March 11-13, 2002 Astro-E2 SWG 1 John P. Hughes Rutgers University Some Possible Astro-E2 Studies of...
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Transcript of March 11-13, 2002 Astro-E2 SWG 1 John P. Hughes Rutgers University Some Possible Astro-E2 Studies of...
March 11-13, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 11
John P. HughesJohn P. HughesRutgers UniversityRutgers University
Some Possible Astro-E2 Some Possible Astro-E2 Studies of Supernova Studies of Supernova
RemnantsRemnants
March 11-13, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 22
Core Collapse SN Science ICore 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, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 33
Core Collapse SN Science IICore Collapse SN Science II
G292.0+1.8 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 +/- 1000 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, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 44
Thermonuclear SupernovaeThermonuclear Supernovae
Nucleosynthesis:Nucleosynthesis: Remnants of SN Ia’s are Remnants of SN Ia’s are more spectrally uniform than core collapse more spectrally uniform than core collapse SNe (note mostly grey/white color at left), SNe (note mostly grey/white color at left), making Astro-E2 spectra easier to making Astro-E2 spectra easier to interpret. Global abundances can help interpret. Global abundances can help constrain models of burning-front constrain models of burning-front propagation in SN Ia (Iwamoto et al 1999)propagation in SN Ia (Iwamoto et al 1999)
Tycho’s SNR Chandra ACIS-S
9’ in diameter
March 11-13, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 55
Thermonuclear SupernovaeThermonuclear SupernovaeSN1006 shows nonthermal SN1006 shows nonthermal synchrotron emission (gray-blue synchrotron emission (gray-blue color at left) from TeV electrons, color at left) from TeV electrons, as well as O, Ne, Mg, & Si as well as O, Ne, Mg, & Si emission from ejecta (red color emission from ejecta (red color at left). Astro-E2 can study the at left). Astro-E2 can study the dynamics of the ejecta and dynamics of the ejecta and nucleosynthesis (confirm nucleosynthesis (confirm presence of Fe). We should presence of Fe). We should observe at various positions in observe at various positions in the SNR (e.g., near center, part the SNR (e.g., near center, part way out, near rim) for velocity way out, near rim) for velocity studies and to see how the studies and to see how the elemental species: O-group, Si-elemental species: O-group, Si-group, Fe-group are distributed.group, Fe-group are distributed.SN1006 NE Chandra ACIS-
S
Portion shown ~8’ square
SNR ~ 35’ in diameter
March 11-13, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 66
Trace element abundancesTrace 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, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 77
Shock PhysicsShock Physics Measure post-shock electron temperature Measure post-shock electron temperature
using line ratios as temperature diagnosticsusing line ratios as temperature diagnostics Best done behind Balmer-dominated shocksBest done behind Balmer-dominated shocks
– Width of broad HWidth of broad H line gives post-shock proton line gives post-shock proton temperaturetemperature
Determine degree of initial post-shock Determine degree of initial post-shock electron-ion temperature equilibrationelectron-ion temperature equilibration
Issue: finding a good Galactic SNR for thisIssue: finding a good Galactic SNR for this– Possibilities: Cygnus loop, RCW 86Possibilities: Cygnus loop, RCW 86
March 11-13, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 88
LMC SNRs: N49BLMC 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, 2002March 11-13, 2002 Astro-E2 SWGAstro-E2 SWG 99
Ejecta in Old Galactic SNRsEjecta in Old Galactic SNRsWe are finding ejecta in more places and in older We are finding ejecta in more places and in older
SNRs (based on SNRs (based on ChandraChandra studies of LMC SNRs). studies of LMC SNRs). Known older Galactic SNRs with signs of ejecta Known older Galactic SNRs with signs of ejecta include:include:
Vela bulletsVela bullets Various places in the Cygnus LoopVarious places in the Cygnus Loop
These are good places to study the range of yields These are good places to study the range of yields from SNe and probe the life cycle of matter.from SNe and probe the life cycle of matter.
A related study: Is the presence of ejecta an A related study: Is the presence of ejecta an explanation for center-filled SNRs (e.g., W44, explanation for center-filled SNRs (e.g., W44, W28)?W28)?– Large angular diameter SNRs – good Astro-E2 targetsLarge angular diameter SNRs – good Astro-E2 targets