Multi-wavelength Observations of
Composite Supernova Remnants
Collaborators:
Patrick Slane (CfA)
Eli Dwek (GSFC)
George Sonneborn (GSFC)
Richard Arendt (GSFC)
Yosi Gelfand (NYU Abu Dhabi)
Paul Plucinsky (CfA)
Daniel Castro (MIT)
Evolution of PWNe inside SNRs
Early Evolution:
•
SNR is in the free expansion stage
•
PWN expands supersonically inside the SNR
and is bounded by a strong shock
•
The PWN shocks the inner SN ejecta that have
not been re-heated by the reverse shock
Late Evolution:
•
The reverse shock heats the inner SN ejecta
and crushes the expanding PWN
•
PWN expansion becomes unstable and
reverberates
•
PWN continues to expand subsonically through
SNR
Gaensler & Slane 2006
Asymmetric Reverse Shock Interaction
• Reverse shock encounters one side of PWN first
and disrupts the nebula – moving pulsar or a
density gradient in the ISM
tSNR = 1000 yr
• After passage of the reverse shock relic PWN
remains (typically observed in the radio) and a
new PWN forms around the pulsar
tSNR = 1800 yr
Bow Shock Nebula
tSNR = 3000 yr
When pulsar’s motion becomes
supersonic, new PWN deforms
into a bow shock - occurs when a
pulsar has traveled 0.67RSNR (van
der Swaluw 2004)
NASA/CXC/M.Weiss
tSNR = 11 400 yr
van der Swaluw et al. 2004
Early Evolution – SN Dust and Ejecta
Kes 75
[Fe II]
Zajczyk et al. 2012
G54.1+0.3
G21.5-0.9
Herschel 70 mm,Chandra X-ray
B0540-69.3
3C 58
Slane et al. 2004
Chandra X-ray image
VLJHK (Mignani et al. 2012)
Crab Nebula
Dust around PWNe
• Information about grain properties can
provide clues on the progenitor type
• Dust surrounding PWNe is ejecta dust, not
mixed with the ISM material
• Dust not been processed by the reverse
shock, no dust destruction
• Dust radiatively heated by the PWN

broadband spectrum of the heating source well
known
Hester 2008
Dust formation in SN ejecta: Theoretical Predictions
• High amount of can form in dense cooling SN ejecta within the first 600–1000 days - consists
primarily of the most abundant refractory elements (e.g., C, Mg, Si, S, and Fe)
• Total dust masses range between 0.1 – 1 M with 2-20% surviving the reverse shock
• Forms in the He envelope where density is high and velocity low – grain properties depend
on mass of the hydrogen envelope
Type IIP
Type IIb
Mass dominated by grains:
> 0.03 μm in Type IIP SNe
< 0.006 μm in Type IIb SNe
(Kozasa,Nozawa et al. 2009)
Kozasa et al. 2009
(Kozasa et al. 1989, 1991; Clayton et al. 1999, 2001; Todini and Ferrara 2001; Nozawa et al. 2003; Bianchi and Schneider
2007; Kozasa et al. 2009, Cherchneff and Dwek 2010)
Crab Nebula: Dust Heating Model
Hester 2008
Heating rate
H 
a
Cooling rate

L  4a

2
2
 L Q( , a)d 
H4  d
2
  B (T )Q ( , a) d 
Ln  non-thermal spectrum of the PWN
Power-law grain size distributions
F(a) = a-a
amin = 0.001 mm amax = 0.03-5.0 mm
a = 0.0-4.0
Distance = 0.5-1.5 pc
(location of the ejecta filaments in 3D models
of Cadez et al. 2004)
Qabs  silicates, carbon (Zubko et al. 2004),
carbon (Rouleau & Martin 1991)
Temim & Dwek 2013
C2 Contours (amax vs. a)
• Size distribution index of 3.5-4.0 and larger
grain size cut-offs are favored
• Larger grains are consistent with a Type IIP
SN – Mass dominated by grains with radii
larger than 0.03 μm in Type IIP, and less than
0.006 μm in Type IIb SNe (Kozasa,Nozawa et
al. 2009)
Best-fit parameters:
Silicates:
Carbon:
a = 3.5
a = 4.0
amax > 0.6 mm amax > 0.1 mm
Md = 0.13 +/- 0.01 M for silicates
Temim & Dwek 2013
Md = 0.02 +/- 0.04 M for carbon
Late Evolution – Interaction with the Reverse Shock
Reverse Shock Interaction: G327.1-1.1
Outflow –
bubble?
• Composite SNR with a shell and
an off-center pulsar wind nebula
Radio
PWN
Neutron
Star
SNR
Shell
• Complex morphology likely
produced by a combination of an
asymmetric reverse shock and
the pulsar’s motion
Sedov model (for d = 9 kpc):
X-ray
PWN
R = 22 pc
104 yr
T = 0.3 keV
MOST Radio, ATCA Radio, Chandra
n0 = 0.12 cm-3 t = 1.8 x
Mtot = 31 Msol
vs = 500 km/s
Temim et al. 2009
G327.1-1.1: X-ray Morphology
• A compact core is embedded in a
cometary PWN
• Prong-like structures originate
from the vicinity of the core and
extend to the NW – outflow from
the pulsar wind?
Compact PWN is more
extended than a point
source
Prongs
Trail
Compact
PWN
Cometary
PWN
350 ks Chandra observation
Two possible scenarios may give rise to cometary
structure:
1. Asymmetric passage of the reverse shock from
the NW – PWN expanding subsonically
2. Bow shock formation due to pulsar’s motion in
the NW direction 
pulsar velocity ~ 770 km/s
Gaensler et al. 2004
Temim et al. 2009, 2014 (in prep)
RS Interaction: MSH 15-56
X-ray, Radio
XMM
3-color
image
Pulsar velocity =
410 km/s
Sedov model (for d = 4 kpc):
Chandra X-ray
R = 21 pc
n0 = 0.1 cm-3
t = 16.5 kyr
Mtot = 100 Msol
T = 0.3 keV
vs = 500 km/s
Temim et al. 2013
Summary
• Composite SNRs serve as unique laboratories for the study of
• SNR/PWN evolution
• Interaction of the PWN with the SNR and surroundings
• Properties of progenitor, pulsar, SN ejecta, freshly formed SN dust
• Nature and evolution of energetic particles in PWNe
• Evolution can be divided into three stages
• Expansion of the PWN into cold SN ejecta (ejecta and dust properties, mass,
dynamics, progenitor type)
• Interaction with the SNR reverse shock (complex morphologies and mixing of
PWN with ejecta)
• Post-reverse shock, subsonic expansion (bow shock formation if pulsar is
moving at a high velocity)
Collaborators:
Patrick Slane (CfA)
George Sonneborn (GSFC)
Richard Arendt (GSFC)
Plucinsky (CfA)
Daniel Castro (MIT)
Eli Dwek (GSFC)
Yosi Gelfand (NYU Abu Dhabi) Paul