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X-ray Emission from PNe. Martín A. Guerrero You-Hua Chu Robert A. Gruendl Univ. of Illinois. APN III, Mt Rainier, 7/30/03. X-ray Expectations. In a simple, adiabatic shock, it is possible to generate X-ray emitting plasma: T X ~ 1.5 10 7 K (v/1000 km/s) 2
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X-ray Emission from PNe Martín A. GuerreroYou-Hua Chu Robert A. Gruendl Univ. of Illinois APN III, Mt Rainier, 7/30/03
X-ray Expectations In a simple, adiabatic shock, it is possible to generate X-ray emitting plasma: TX ~ 1.5107 K (v/1000 km/s)2 PN central stars have fast stellar winds with terminal velocities up to 4,000 km/s ==> TX ~ 108 K PNe show fast collimated outflows with velocities >1,000 km/s (e.g. Hen 3-1475) ==> TX ~ 107 K Coronalactivityfrom AGB stars or binary companions
ROSAT Observations of PNe ROSAT made useful observations of >60 PNe (Guerrero, Chu, & Gruendl 2000) Only three PNe were marginally resolved A 30 -- Chu et al. 1997 BD +30º3639 -- Leahy et al. 2000 NGC 6543 -- Kreysing et al. 1992 Two additional PNe showed a hard X-ray component NGC 7293 -- Leahy et al. 1994 NGC 7009 -- Guerrero et al. 2000 Chandra spatial resolution -- 15 times sharper XMM collecting area -- 15 times larger Spectral resolution -- 10 times better
Chandra and XMM Observations of PNe Chandra and XMM observations of 14 PNe 6 detections of diffuse X-ray emission BD+30 3639 -- Kastner et al. 2000 NGC 6543 -- Chu et al. 2001 NGC 7027 -- Kastner et al. 2001 NGC 7009 -- Guerrero et al. 2002 Mz 3 -- Kastner et al. 2003 Hen 3-1475 -- Sahai, this meeting 3(4?) detections of point sources at the central star NGC 6543, NGC 7293 -- Guerrero et al. 2001 Mz 3 -- Kastner et al. 2003 Hen 3-1475 (?) -- this talk 4 non-detections of diffuse X-ray emission Hen 2-90, M 1-16, NGC 246, NGC 7293
PNe with Diffuse X-ray Emission NGC 6543 -- Chu et al. 2001; Guerrero et al. 2001 B = X-ray, R= H-alpha, G = [N II]
PNe with Diffuse X-ray Emission NGC 7009 -- Guerrero et al. 2002
PNe with Diffuse X-ray Emission BD+30 3639 Kastner, Soker, Vrtilek, & Dgani 2000 NGC 7027 Kastner, Vrtilek, & Soker 2001
PNe with Diffuse X-ray Emission Mz 3 -- Kastner et al. 2003
PNe with Diffuse X-ray Emission Hen 3-1475, Sahai (this meeting)
X-ray Spectra of Hot Gas in PNe NGC 7009 T=1.7106 K Mz 3 T=3-6106 K Hen 3-1475 T=2.4106 K=>400 km s-1 BD+30 3639 T=3.0106 K NGC 7027 T=3106 K NGC 6543 T=1.8106 K
Chandra and XMM-Newton Analysis of PNe Morphology LX (erg/s) T (106 K) N (cm-3) NGC 7009 -- ~31031 1.7 20 NGC 6543 limb-bright. 1.01032 1.8 50 NGC7027 bipolar? ~ 1032 ~3 150 BD+30 3639 -- 1.31032 3 200 Mz 3 bipolar-jet? 31031 3-6 -- Hen 3-1475 -- ~1033 2.4 --
PNe without Diffuse X-ray Emission … PNe with modest velocity collimated outflows: Hen 2-90, M 1-16 Evolved PNe: NGC 246, NGC 7293 … but NGC 7293 central star!
PNe with X-ray-emitting Central Stars Chandra revealed hard X-ray point sources at the central stars of NGC 7293 and NGC 6543 (Guerrero et al. 2001) NGC 7293 central star shows variability in X-rays, as well as in the H-alpha line (Gruendl et al. 2001) Coronal activity from an unseen companion star (Guerrero et al. 2001; Soker & Kastner 2002) NGC 6543: a companion star or shocks in its fast stellar wind More recently, Mz 3 (Kastner et al. 2003), and maybe Hen 3-1475
X-rays from PNe in a Nutshell (so far) • Sharp shell morphology • Young PNe (X-rays don’t last long) • Central stars • Fast collimated outflows (I mean, real fast) • Something is going on along the major axis 4 more PNe have been observed by Chandra and 12 more will be observed by Chandra and XMM