New high-energy observaons of supernova explosions

Brian Grefenstee SRL, Caltech [email protected] FOE II Raleigh, NC, June 4, 2015 Thermonuclear Supernova

• What’s the progenitor? – C+O core plus massive star: • Chandrasekhar limit exceed and ignion of C in the core. • Sub-Chandrasekhar explosions. – C+O core plus He core: • Double-degenerate mergers. • How does the star explode? – Sub-sonic deflagraon wave or super-sonic detonaon?

2 Thermonuclear Supernova

• What’s the progenitor? – C+O core plus massive star: • Chandrasekhar limit exceed and ignion of C in the core. • Sub-Chandrasekhar explosions. – C+O core plus He core: • Double-degenerate mergers. • How does the star explode? – Sub-sonic deflagraon wave or super-sonic detonaon?

3 Thermonuclear Supernova

• What we know: – Opcal light curve is powered by radioacve decay: • 56Ni à 56Co à 56Fe • (6 days) à (77 days) 56Ni – Opcal emission is highly reprocessed gamma-ray lines. 56Co • Complicated radiave transfer process. • How much 56Ni is uncertain.

– X-rays and gamma-rays are simple(r). • Only Compton scaering and photoelectric absopron.

4 Core-Collapse Supernova

• Collapse of a massive star. • Core collapses unl a proto-neutron star is formed. • Hard surface causes a “bounce”. • Shock wave blows apart the star.

5 Core-Collapse Supernova

• Standard models fails in 1-D. – Spherical symmetry à stalled shock. • Soluons: – Neutrino heang and convecon (and/or turbulence in 3D). • Leads to lopsided explosions. – Rotaon and/or magnec fields. • Leads to collimated jets.

6 Core-Collapse Supernova Ott et al • Standard models fails in 1-D. – Spherical symmetry à stalled shock. • Soluons: – Neutrino heang and convecon (and/or turbulence in 3D). • Leads to lopsided explosions. – Rotaon and/or magnec fields. • Leads to collimated jets.

7 Core-Collapse Supernova Moesta et al • Standard models fails in 1-D. – Spherical symmetry à stalled shock. • Soluons: – Neutrino heang and convecon (and/or turbulence in 3D). • Leads to lopsided explosions. – Rotaon and/or magnec fields. • Leads to collimated jets.

8 Integral

9 • 3.5 Mpc away (roughly 1 / 100 years). • “Run of the mill” Type Ia explosion in opcal.

10 SN 2014J • 56Co gamma-ray lines detected at ~850 and ~1200 keV

• Confirmaon that 0.6 M¤ was produced in the event.

Integral

Churazov et al. Nature (2014) 11 SN 2014J The and Burrows, arxiv 1402.4806

12 SN 2014J The and Burrows, arxiv 1402.4806

13 SN 2014J

• Gamma-rays are Compton down- The and Burrows, arxiv 1402.4806 scaered to hard X-ray energies.

• Hard X-rays give clues about the distribuon of 56Ni in the explosion.

• Benchmark “W7” model (from Nomoto et al, 1984) gives a predicon for hard X-ray flux vs me. Silicon/Magnesium

14 SN 2014J NuSTAR

Iron Silicon/Magnesium

Harrison et al. (2015), in prep 15 SN 2014J NuSTAR

Iron Silicon/Magnesium

Harrison et al. (2015), in prep 16 SN 2014J NuSTAR

Iron Silicon/Magnesium

Harrison et al. (2015), in prep 17 SN 2014J NuSTAR

Iron Silicon/Magnesium

Harrison et al. (2015), in prep 18 Core Collapse Supernovae

19 Cassiopeia A

• Observed so X-rays tells us about the shocked ejecta.

• Doppler maps show complex structure.

• Low-energy X-rays only show shocked ejecta, not the true distribuon of the ejecta.

20

Cassiopeia A

• Observed so X-rays tells us about the shocked ejecta.

• Doppler maps show complex structure.

• Low-energy X-rays only show shocked ejecta, not the true distribuon of the ejecta. Delaney et al., ApJ (2010)

21

Core Collapse Supernovae

T1/2 ~60 years Iron Silicon/Magnesium

22 Cassiopeia A

Grefenstee et al., Nature (2014)

23 Cassiopeia A

24 Cassiopeia A

25 Cassiopeia A Preliminary!

26 Cassiopeia A Preliminary!

27 Cassiopeia A Preliminary!

Grefenstee et al., (2015) in prep

Doppler map of 44TI

28 Cassiopeia A Preliminary!

29 Cassiopeia A Preliminary!

30 Cassiopeia A Preliminary!

Fe Doppler Map DeLaney et al. 2010 ApJ 725 2038

31 SN 1987A

• Neutrino detecons confirmed collapse of the core into a neutron star.

• 56Co lines emerged months before expected, heavy mixing of 56Ni.

• Low-significance redshi of 500 km / sec detected. Chandra/HST Image: NASA/CXC

32 SN 1987A

• Neutrino detecons confirmed collapse of the core into a neutron star.

• 56Co lines emerged months before expected, heavy mixing of 56Ni.

• Low-significance redshi of 500 km / sec detected. Tueller et al, (1990)

33 SN 1987A NuSTAR

Boggs et al., Science (2015)

700 +/- 400 km / sec (90 % errors)

34 SN 1987A NuSTAR

35 Summary

• Gamma-ray observaons of SN2014J provide an independent confirmaon of 0.6 M of 56Ni is produced in the explosion.

• The first hard X-ray observaons of a Type Ia supernova imply a high level of mixing of the 56Ni. – How do we explain this?

• Ejecta from core-collapse supernova are intrinsically asymmetric (N=2) and appear to be dominated by large-scale anisotropies. – No jets (yet).

36 Outlook

• How do we explain the Fe/Ti differences? – Both created in alpha-rich freezout and/or paral Si burning, so what’s driving the differences?

• Need a link between simulaons (~1 s post- bounce) and ejecta morphology. – 3D turbulence codes coming online soon*, including explosive nucleosynthesis**.

• Wait for the next local Type Ia or Type II.

37