1. Supernova Interaction with Dense Mass Loss
Roger Chevalier
University of Virginia
X-ray, Chandra

2. Type IIP supernovae Shock breakout emission Diffusive release of
energy in H envelope
Radioactive tail (56Co)

3. Circumstellar interaction
X-ray and
radio emission

4. IIn’s Ia
IIP
Zhang+ 12

5. Broad Ha formed by electron scattering in the wind
SN 2010jl
Smith et al
2008
SN 2010jl Ha
narrow P Cygni
line km/s
el. scatt.
wing
NOT: Fransson….
Broad Ha formed by electron scattering in the wind
(Chugai 2001 on SN 1998S)
Requires Thomson optical depth of > 1 in the wind

6. SN 2010jl
6000 K K 6
Fransson+ 13

7. SN 2010jl X-Rays (Chandra) Dec 2010 (t=2 mnth), 7e41 ergs/s (unabs),
NH~1e24 cm-2, T≥10 keV
Oct 2011, 7e41 ergs/s,
NH~3e23 cm-2, T≥10 keV
Jun 2012, 5e41 ergs/s,
NH~5e22 cm-2, T≥10 keV
P. Chandra, RAC,…

8. SN 2010jl Oct 2012
XMM
NuSTAR
Zoglauer, Ofek+ HEAD

9. Optically thick (in optical)
X-ray emission
(radio absorbed)
X-ray photoionized
region
At high densities, the hard, forward shock X-ray emission dominates

10. Supernova in dense wind (rw=D/r2 to Rw)
Radiation mediated shock transition covers optical depth c/vsh
tw>c/vsh
Radiation dominated shock propagates into wind
Radiation breakout when Rsh=Rd=kDvsh/c, characteristic diffusion radius in the wind
Viscous shock at larger radii

11. Chevalier & Irwin 2011

12. SN 2010gx and related objects: Rw<Rd Type I (Quimby objects)
Pastorello et al. 2010

13. Rw = 2.5×1015 cm, D = 1018 g cm−1,
and E = 2 × 1051 erg
(Ginzburg & Balberg 12)
SN 2010gx

14. Magnetar Models for SLSN-I Inserra+ 2013

15. SN2006gy X-rays 1.5 x 1039 erg/s soft (Smith et al. 2007)
< 1 x 1040 erg/s (Ofek et al. 2007)
L(optical) ~ 2 x 1044 erg/s

16. SN 2006gy
SN 2010jl
D*= M/yr at 100 km/s
RAC + Irwin 2012

17. Breakout X-rays decreased by
Inverse Compton cooling by photospheric photons more important than bremsstrahlung
Comptonization in the cool wind reduces energy of the highest energy photons
down to ~me c2/τ2 = 511/τ2 keV
Photoelectric absorption in the cool wind
Photoionization can be a factor

18. Analogous to cooling accretion onto a white dwarf.
Increasing optical depth to Thomson
scattering until accretion reaches
the Eddington rate, when t~c/vs WD
Kylafis & Lamb 1982

19. Rise to maximum
due to rising T
Grassberg, Imshennik, & Nadyozhin 1971

20. SN 2006oz
Days before max
Leloudas et al. 12

21. A clearer case of shock breakout SN 2011ht (IIn)
Roming et al. 12

22. SNe with dense surroundings
Up to several M lost in yrs to 100s of years before the explosion
Velocity of circumstellar matter typically 100s km/s
What are they?

23. Proposals for dense surroundings
Mass loss driven by gravity-waves from convection in late burning phases (Quataert & Shiode 12)
Pulsational pair instability (Woosley+ 07)
Binaries (RAC 12, Barkov & Komissarov 11, Thone et al 12, Soker 12)

24. Inspiral stops outside core Inspiral continues
Massive star
binary
Supernova
Neutron star
Common envelope
Mass loss
Inspiral stops outside core Inspiral continues
NS/BH
He star SN
TZO SN BH
Inspiral
M loss +
TZO SN BH

25. Outcome depends on the initial period (separation) of binary
NS + massive star
Outcome depends on the initial
period (separation) of binary
or SN?
Terman et al. 95

26. SN IIn observations
Binary scenario
Narrow emission and absorption lines give 100 to 1000 km/s
Up to solar masses in 10’s to 100’s of yr before explosion
Rate is 4-7% of CCSN rate, so (8-13)e-4 yr-1 in Galaxy (W. Li,….)
Asymmetry
Outflow velocity related to escape velocity: 100’s of km/s
Up to solar masses in <1000 yr before explosion
Rate estimated from # of HMXBs >2e-4 yr-1 in Galaxy (Podsiadlowski…)
Asymmetric mass loss

27. Radiated ~4e51 ergs over 4.7 yr
SN 2003ma
Radiated ~4e51 ergs over 4.7 yr
Estimate >1052 ergs explosion energy
Rest+ 2011

28. Conclusions
Most core collapse supernovae have low density surroundings, consistent with the progenitor star wind
Some supernovae have dense surroundings
An extended, optically thick medium gives IIn characteristics
They can be optically highly luminous, although X-ray faint
Superluminous supernovae without “n” characteristics may also be powered by dense interaction
Reason for the dense mass loss uncertain – common envelope evolution is a suggestion