Supernova Neutrinos Christian Y Cardall Oak Ridge National

Supernova Neutrinos Christian Y. Cardall Oak Ridge National Laboratory Physics Division University of Tennessee, Knoxville Department of Physics and Astronomy

Core-collapse supernovae Survey of collapse simulations Supernova neutrino signals New effects at small ∆m 2? Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Core-collapse supernovae Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

SN 1998 aq (in NGC 3982) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Spectral classification of supernovae: Type Ia (no H, strong Si) Type II (obvious H) Type I (no H) Type Ic (no H, He, Si) Type Ib (no H, obvious He) Filippenko (1997) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Some key ingredients are Neutrino transport/interactions, Spatial dimensionality; Dependence on energy and angles; Relativity; Comprehensiveness of interactions; (Magneto)Hydrodynamics/gravitation, Dimensionality; Relativity; Equation of state/composition, Dense matter treatments; Number and evolution of nuclear species; Diagnostics, Accounting of lepton number; Accounting of energy; Accounting of momentum. Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

The observables to understand include Explosion (and energy thereof); Neutrinos; Remnant properties, Mass, spin, kick velocity, magnetic fields; Gravitational waves; Element abundances; Measurements across the EM spectrum, IR, optical, UV, X-ray, gamma-ray; images, light curves, spectra, polarimetry. . . Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Survey of collapse simulations Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 1 S 1 M GR N N GR 2 S N B GR B 3 S N B GR B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 3 S 0 M GR N 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N 2 S 3 M GR N

Two observables beyond explosion… Accretion continues until the stalled shock is reinvigorated: relation between neutron star mass and delay to explosion The abundance of nuclei with a closed shell of 50 neutrons The electron fraction… is set by neutrino interactions: Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Fluid dynamics: 2 D, 3 D Neutrino transport: 1 D + 1 D Neutrino transport: 2 D + 0 D, 3 D + 0 D Mezzacappa et al. (1998) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 Fryer & Warren (2002)

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 2 S 3 S 1 S 1 M GR N 3 S 0 M GR N 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N N GR N B Neutron star mass too small; heating drives explosion too soon. B N=50 overproduction; Ye too low. GR N B GR B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 2 S 3 M GR N

Fluid dynamics: 1 D Neutrino transport: 1 D + 2 D Liebendörfer et al. (2001, 2004) Rampp & Janka (2000, 2002) Thompson, Burrows, & Pinto (2002) Kitaura, Janka, & Hillebrandt (2006) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 2 S 3 S 1 S 1 M GR N 3 S 0 M GR N 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N N Explosion only for 8 -10 M stars with O-Ne-Mg cores. GR N B GR B N B Reasonable neutron star mass; accretion continues during delay. Reasonable N=50 element production expected; ejected matter has Ye > 0. 46. May explain some subluminous Type II-P. GR B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 2 S 3 M GR N

Fluid dynamics: 2 D Neutrino transport: 2 D + 1 D Burrows et al. (2006) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 Swesty & Myra (2005)

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 2 S 3 S 1 S 1 M GR N 3 S 0 M GR N 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N N Explosion for 11, 15, 25 M progenitors. GR N B Some neutrino transport details left out; is the acoustic mechanism physical? GR B N B GR Reasonable neutron star mass; accretion continues during delay. Not yet clear if Ye gives reasonable nucleosynthesis or if the model is resolved. B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 2 S 3 M GR N

Fluid dynamics: 2 D Neutrino transport: 1. 5 D + 2 D Buras et al. (2006) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 2 S 3 S 1 S 1 M GR N 3 S 0 M GR N 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N N Full 180º allows an 11 M star to explode; what about higher mass progenitors? GR N B GR B N B Reasonable neutron star mass; accretion continues during delay. Reasonable N=50 element production expected; some of ejecta has Ye > 0. 5. Acoustic mechanism not yet probed. GR B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 2 S 3 M GR N

Neutrino radiation transport Magnetohydrodynamics 2 S 0 M GR N 1 S 2 S 3 S 1 S 1 M GR N 3 S 0 M GR N N GR N B GR B Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 1 S 2 M GR N 2 S 1 M GR N 1. 5 S 2 M GR N 3 S 1 M GR N 2 S 3 M GR N

Supernova neutrino signals Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 Did anyone do gravitational collapse as a Fermi problem? Assume the stellar core is basically a white dwarf: a Chandrasekhar mass of 1. 4 M and about 104 km. Assume that the neutron star it collapses to is essentially a giant nucleus, and hence has density n = 0. 16 fm-3. From the mass and final density, Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 How long will it take to collapse? The free-fall time scale is The iron core is roughly half protons before collapse. Electron capture converts each proton to a neutron with the emission of an antineutrino. Assume the neutrinos are trapped (check the consistency of this later). Then the number density of antineutrinos is half the final nucleon density. Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 From the number density of antineutrinos, find their typical energy from the inter-particle spacing: On what timescale will the neutrinos diffuse out? This ‘validates’ the assumption of neutrino trapping. Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 Almost forgot: the gravitational binding energy released during collapse will be released in neutrinos. If neutrinos are trapped we expect all flavors to be produced. They will be emitted with a hierarchy of energies because differences in their interactions cause them to decouple at different radii: Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 ~ 1 s hydrodynamic simulations with decent neutrino transport (Wilson 1984) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino predictions ca. 1987 ~ 20 s ‘stellar evolution’ with crude transport Burrows and Lattimer 1986 Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Tarantula Nebula Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 SN 1987 A

The lucky messengers… Each “event” involves ~109 “messengers, ” with at most 1 “detected” Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 Raffelt (1999) SN 1987 A sent ~1058 “messengers, ” with ~two dozen detected

Prediction vs. observation Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006 Burrows and Lattimer (1987)

A neutrino window into the supernova… Buras et al. (2005) Liebendörfer et al. (2004) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

…could provide information about, for instance, rotation and the nuclear equation of state. Thompson et al. (2005) Sumiyoshi et al. (2006) Pons et al. (2001) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Neutrino mixing unknowns: 13 and hierarchy Raffelt (2005) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

New effects at small ∆m 2? Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Duan et al. (2006) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Duan et al. (2006) Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006

Core-collapse supernovae Survey of collapse simulations Supernova neutrino signals New effects at small ∆m 2? Supernova Neutrinos Christian Y. Cardall NOW 2006, Conca Specchiulla, Italy, 9 -16 September 2006