Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Supernova Neutrinos Нейтрино от сверхновые Georg Raffelt, 17 th Lomonosov Conference, Moscow

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Core-Collapse Supernova Explosion Neutrino cooling by diffusion Collapse of degenerate core Huge rate of low-E neutrinos (tens of MeV) over few seconds in large-volume detectors A few core-collapse SNe in our galaxy per century Once-in-a-lifetime opportunity

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Three Distinct Phases of Neutrino Emission Shock breakout De-leptonization of outer core layers Cooling on neutrino diffusion time scale Spherically symmetric Garching model (25 M ⊙ ) with Boltzmann neutrino transport Explosion triggered

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Neutrino Signal of Supernova 1987A Kamiokande-II (Japan) Water Cherenkov detector 2140 tons Clock uncertainty  1 min Irvine-Michigan-Brookhaven (US) Water Cherenkov detector 6800 tons Clock uncertainty  50 ms Within clock uncertainties, all signals are contemporaneous

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Operational Detectors for Supernova Neutrinos Super-K (10 4 ) KamLAND (400) SNO+ (300) In brackets events for a “fiducial SN” at distance 10 kpc LVD (400) Borexino (100) IceCube (10 6 ) Baksan Baksan (100) (100) HALO HALO (tens) (tens) Daya Bay Daya Bay (100) (100)

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 IceCube as a Supernova Neutrino Detector Pryor, Roos & Webster, ApJ 329:355, Halzen, Jacobsen & Zas, astro-ph/ Demirörs, Ribordy & Salathe, arXiv: SN signal at 10 kpc 10.8 M sun simulation of Basel group [arXiv: ] Accretion Cooling

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Next Generation Large-Scale Detectors (2020+) Megaton water Cherenkov detector Notably Hyper-Kamiokande SN neutrino statistics comparable to IceCube, but with event-by-event energy information Scintillator detector (tens of kilotons) - Original LENA concept 50 kt - JUNO (20 kt) in China for reactor nus - RENO-50 (20 kt) in Korea for reactor nus - Baksan Large Vol. Scintillator Detector (20 kt) IceCube Gen-2 - Dense infill (PINGU) - Larger volume (statistics for high-E events) Doubling the number of optical modules

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Local Group of Galaxies Current and next-generation neutrino detectors sensitive out to few 100 kpc With megatonne class (30 x SK) 60 events from Andromeda

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 SN Distance Distribution and Peak Count Rate Peak count rate in JUNO (20 kt) depending on SN distance probability in Milky Way Model uncertainty (Garching) JUNO Yellow Book, in preparation (2014)

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Crab Nebula Core-Collapse Supernova Explosion Mechanism

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Shock Revival by Neutrinos Georg Raffelt, MPI Physics, Munich S Si O Shock wave PNS Stalled shock wave must receive energy to start re-expansion against ram pressure of infalling stellar core Shock can receive fresh energy from neutrinos! NOW 2014, 7–14 Sept 2014, Otranto, Italy

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Exploding 3D Garching Model (20 M SUN ) Melson, Janka, Bollig, Hanke, Marek & Müller, arXiv: D3D Neutrino opacity reduced (few 10%) by strange quark contribution to nucleon spin (thick lines) “Standard” neutrino opacity (thin lines)

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Exploding 3D Garching Model (20 M SUN ) Melson, Janka, Bollig, Hanke, Marek & Müller, arXiv:

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Variability seen in Neutrinos (3D Model) Tamborra, Hanke, Müller, Janka & Raffelt, arXiv: See also Lund, Marek, Lunardini, Janka & Raffelt, arXiv:

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Sky Map of Lepton-Number Flux (11.2 M SUN Model) Tamborra, Hanke, Janka, Müller, Raffelt & Marek, arXiv: Positive dipole direction and track on sky

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Growth of Lepton-Number Flux Dipole Overall lepton-number flux (monopole) depends on accretion rate, varies between models Maximum dipole similar for different models Dipole persists (and even grows) during SASI activity SASI and LESA dipoles uncorrelated Tamborra et al., arXiv: Monopole Dipole

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Flavor Oscillations Diffuse SN Neutrino Background

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Diffuse Supernova Neutrino Background (DSNB) Beacom & Vagins, PRL 93:171101,2004

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Experimental DSNB Limits Super-Kamiokande Collaboration, arXiv: SuperK I-III SuperK IV (with neutron tagging) KamLand Super-K with Gadolinium enhancement (neutron tagging) will strongly improve sensitivity

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 DSNB Sensitivity of JUNO 20 kt Scintillator Detector JUNO Collaboration, Yellow Book, arXiv: SuperK Limit JUNO 90% Exclusion Sensitivity (10 y) JUNO detection sensitivity (10 y) Example for typical parameters

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Crab Nebula Supernova Neutrino Flavor Conversion

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Gribov and Pontecorvo 1968 Bruno Pontecorvo (1913–1993) Vladimir Gribov (1930–1997) Learning about astrophysical sources with neutrinos Learning about neutrinos from astrophysics and cosmology

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Flavor Oscillations in Core-Collapse Supernovae Neutrino sphere MSW region Neutrino flux Flavor eigenstates are propagation eigenstates Neutrino-neutrino refraction causes a flavor instability, flavor exchange between different parts of spectrum

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Self-Induced Flavor Conversion Flavor content exchanged between different momentum modes (or nus and anti-nus changing together) No net flavor conversion of ensemble (in contrast to MSW conversion) Instability required to get started - Exponentially growing off-diagonals in density matrix - Linearized stability analysis to find growing modes Interacting neutrino system: Coupled oscillators - Collective harmonic oscillation modes - Exponential run-away modes

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 New Development: Spatial Symmetry Breaking Mirizzi, Mangano & Saviano arXiv: See also Duan et al, arXiv: , Chakraborty et al., arXiv: Without flavor oscillations: free streaming Space coordinate along beam Time

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Instability Footprints Chakraborty, Hansen, Izaguirre & Raffelt, arXiv: Shock wave Density profile Small-scale modes “fill in” the stability footprint for large neutrino density Largest-scale mode is “most dangerous” to cross SN density profile Axial-symmetry breaking (MAA) instability (normal ordering NH) is “more dangerous” to trigger self-induced flavor conversion Traditional “bimodal” instability (inverted mass ordering IH)

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Status of Collective Flavor Conversion Self-induced flavor conversion is an instability in flavor space of the interacting neutrino ensemble Space-time dependent phenomenon (not simply stationary or homogeneous) Solutions do not respect symmetries of initial system Instabilities can occur on all scales Essentially back to the drawing board …

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Three Phases – Three Opportunities “Standard Candle” SN theory Distance Flavor conversion Multi-messenger time of flight Strong variations (progenitor, 3D effects, black hole formation, …) Testing astrophysics of core collapse Flavor conversion has strong impact on signal EoS & mass dependence Testing Nuclear Physics Nucleosynthesis in neutrino-driven wind Particle bounds from cooling speed (axions …) Prompt e burst AccretionCooling

Georg Raffelt, MPI Physics, Munich17 th Lomonosov Conference, Moscow, 20–26 Aug 2015 Looking forward to the next galactic supernova Neutrinos from next nearby supernova: A once-in-a-lifetime opportunity: Do not miss it! A once-in-a-lifetime opportunity: Do not miss it!