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Supernovae and Neutrinos: the Crossroads John Beacom, the Ohio State University Supernovae and Neutrinos: The Crossroads John Beacom, The Ohio State University John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 1 Gateway: Astrophysics Neutron stars Black holes GW sources Cosmic rays Chemical elements Galaxy Feedback Supernovae John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 2 Gateway: Particle Physics s Origin oF mass Mixing, CP violation Collective eFFects Dark matter New Forces New particles Neutrinos John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 3 Crossroads Origin oF mass Neutron stars Mixing, CP violation Black holes Collective eFFects GW sources Dark matter Cosmic rays New Forces Chemical elements New particles Galaxy Feedback X Neutrinos Supernovae John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 4 Why a Crossroads? To understand supernovae only neutrinos can reveal these extreme conditions To understand neutrinos only these extreme conditions can reveal particle properties John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 5 Crossroads: Past Versus Future Are we ready? For Milky Way burst detection? To precisely detect the DSNB? To detect extragalactic minibursts? To advance multimessenger astrophysics? To probe physics beyond the standard model? To make neutrino astronomy real? What should we do diFFerently? John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 6 SN 1987A: Our Rosetta Stone IMB KamII Observation: Type II supernova Observation: The neutrino progenitors are massive stars precursor is very energetic Theory: Core collapse makes a proto-neutron star and neutrinos John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 7 What Does This Leave Unknown? Total energy emitted in neutrinos? Partition between Flavors? Emission in other particles? Spectrum oF neutrinos? Neutrino mixing eFFects? ! Supernova explosion mechanism? Nucleosynthesis yields? Neutron star or black hole? Electromagnetic counterpart? Gravitational wave counterpart? ! and much more! John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 8 Distance Scales and Detection Strategies N >> 1 : Burst N ~ 1 : Mini-Burst N << 1 : DSNB Gpc kpc Mpc Rate ~ 0.01/yr Rate ~ 1/yr Rate ~ 108/yr high statistics, object identity, cosmic rate, all Flavors burst variety average emission John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 9 Scientific Opportunities: MW Burst John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 10 Question 1: The Source What are the mechanisms oF core collapse? Idealized; simple Realistic; complex Oak Ridge group (2015) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 11 Question 2: The Messengers How do neutrinos mix in core collapse? Idealized; simple Realistic; complex Trapping Decoupling Free-streaming 11 1.51.5 n fwd (0) n 11 n bwd G ne (z,t) (z,t) (z,t) eq ee n fwd eq ee ne eq ee r r 0.50.5 r (z) / 0.50.5 n bwd n G Dighe and Smirnov (1999); RaFFelt slide 00 00 0 10001000 20002000 0 10001000 20002000 z z Capozzi, Dasgupta, Mirizzi, Sen, Sigl (2019) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 12 The Flavor Problem: Experiment Need all Flavors to measure the total emitted energy Need all Flavors to test eFFects of neutrino mixing 4 ⌫¯e Precise (~ 10 events in Super-K) ⌫µ, ⌫⌧ , ⌫¯µ, ⌫¯⌧ Inadequate (~ 102 events in KL+) ⌫e Inadequate (~ 102 events in Super-K) How will we ensure complete flavor coverage? John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 13 Multi-kton-Scale Neutrino Detectors Super-K JUNO DUNE 32 kton water 20 kton oil 40 kton liquid argon Japan China United States running building preparing Together, excellent potential For MeV neutrino astronomy John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 14 Focus on Measuring Nue Super-K JUNO DUNE ~ 102 events ~ 102 events ~ 103 events 10 10 16 e + O ν 12 8 8 e + C erg] 6 + e- erg] 6 52 e 52 x x [10 [10 tot 4 tot 4 e e ν E E - ? ? ν e + e 2 allowed 2 solid: Gd dashed: no Gd 0 0 0 5 10 15 20 25 30 0 5 10 15 20 25 30 <E > [MeV] <Eν > [MeV] e e Laha and Beacom 2013 Laha and Beacom 2014 DUNE uncertain due to cross section, detector response Need better understanding of neutrino+nucleus! John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 15 The Timeline Problem present and near Future beyond that large detectors maybe not time used to measure anymore neutrino mixing Who will build detectors For supernova neutrinos? John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 16 What is Needed? Interactions: Understand neutrino-nucleus cross sections This should include diFFerential cross sections, particle emission, etc. Detectors: Understand detection response, especially DUNE Coordination: Ensure Full coverage, especially Flavors Simulations: Robust predictions to at least 10 seconds Theory: Solution oF Flavor mixing problem Costs and beneFits oF “Flavor censorship” John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 17 Question 3: The Consequences What are the dynamics oF the supernova? Idealized; simple Realistic; complex Core collapse leads to Luminosity (erg/s) Type II SN (= red supergiants) shock breakout an outgoing shock oF 1045 51 internal energy radioac5ve energy total energy ~ 10 erg 44 10 cooling envelope 1043 plateau ~0.5hr Light signal has total 1042 Luminosity 49 @ UV & op5cal tail energy ~ 10 erg 1041 1040 0.1 d 1d 10 d 100 d 1000 d 5me Tanaka (2017) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 18 Question 4: The Multimessengers How do these signals reveal the dynamics? Idealized; simple Realistic; complex 54 Astronomers detect the νe 52 νe ]) νx optical light -1 50 GW EM 48 pre-SN νe Physicists detect the 46 SBO 44 plateau neutrinos 42 Log (luminosity [erg s 40 progenitor Nobody detects 38 9 6 3 0 -2 0 2 4 6 8 anything else Log (time relative to bounce [s]) Nakamura et al. (2016) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 19 The Waiting Problem Will we be ready to detect a supernova neutrino burst? John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 20 How Will We See the Supernova? Connection to astronomy crucial, but optical data are lacking Enter OSU’s “ASAS-SN” (All-Sky Automated Survey For SN) Host Galaxy log L/L? -3 -2 -1 0 1 100 10 1 Offset (kpc) 0.1 ASAS-SN Other Prof. Amateurs -15 -16 -17 -18 -19 -20 -21 -22 -23 -24 -25 -26 Host Galaxy MKs Discovering and monitoring optical transients to 18th mag. John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 21 What is Needed? Detectors: Ensure readiness with practiced alarms Coordination: Test procedure with practiced alarms, alerts Pointing: Decide iF triangulation works or not This needs a new paper to check Beacom and Vogel (1999) versus Brdar, Lindner, Xu (2018) Theory: Clear predictions For possible signals Observers: New Facilities For Full Milky Way coverage Build on Adams, Kochanek, Beacom, Vagins, Stanek (2013), Nakamura et al. (2016) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 22 Scientific Opportunities: DSNB John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 23 Question 1: The Template What are the properties oF core collapse on average? Bays et al. [Super-Kamiokande] (2012) Horiuchi , Beacom, Dwek (2009) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 24 Question 2: The Multitude What is the cosmic rate oF core collapses? Horiuchi et al. (2011) Lien, Fields, Beacom (2010) John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 25 What is Needed? 3 10 GADZOOKS! -1 Full deployment oF Gd in Super-K 2 Reactor 10 !e 1 Supernova !e 10 (DSNB) Atmospheric Full plans For Gd in Hyper-K !! !e [(22.5 kton) yr MeV] 0 e 10 dN/dE See Vagins talk -1 10 -2 10 0 5 10 15 20 25 30 35 40 Measured Ee [MeV] New ways to reduce backgrounds Further Spallation backgrounds: Li and Beacom, 2014+ Atmospheric Backgrounds: Zhou and Beacom, 2019+ Advance, update astrophysical constraints ASAS-SN nearby supernova rate Forthcoming Other new data on SFR, direct BH detection, etc. John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 26 Scientific Opportunities: Nearby Galaxies John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 27 Question 1: The Variations What are the properties oF core collapse in extremes? 0.15 SN (4 Mpc) DSNB (1 day) Invisible (1 day) H2O 0.1 H O + GdCl 0.05 2 3 dN/dE 1/[MeV Mton] 0 0 10 20 30 40 50 Visible Energy [MeV] Idea From Ando, Beacom, Yuksel (2005) Nakazato and collaborators John Beacom, The Ohio State University Supernova Neutrinos at the Crossroads, Trento, Italy, May 2019 28 Question 2: The Verifications What are the varieties and rates oF transients? 15 observed (with SN 2008S-like) 11 observed (without SN 2008S-like) Neutrino bright, optically bright: 15 B-band 15 CCSNe 2.5 cosmic SFR extrapolation Core-collapse supernova NOROT-UV ROT-UV NOROT-H 2 ROT-H Neutrino bright, optically dim: 11 CCSNe 10 Core-collapse to black hole 1.5 B-band NOROT-UV Neutrino dim, optically bright: 1 CCSN rate [/yr] ROT-UV Type Ia supernova 5 NOROT-H Supernova impostor CCSNe in galaxy sample ROT-H 0.5 Neutrino dim, optically dim: 0 0 All the time! 0246 8 10 Distance D [Mpc] Horiuchi et al.
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