MULTIMESSENGER ASTRONOMY GSSI, November 2015, L’Aquila Giulia Pagliaroli
Outline High-Energy Cosmic Neutrinos Core-Collapse Supernovae Strange Stars
HIGH ENERGY COSMIC NEUTRINOS Collaboration: G.P., A.Palladino, F. Vissani and F.L.Villante References: A. Palladino, G.P., F.L. Villante, F. Vissani: arXiv: G. P., A. Palladino, F. Vissani, F.L. Villante: arXiv: A.Palladino, G.P., F.L. Villante, F. Vissani, Phys.Rev.Lett.114 (2015) 17, F. Vissani, G. P. and F. L. Villante, JCAP 1309 (2013) 017
Flavor Ratios of High Energy Neutrinos Pion Decay Charmed mesons decay Beta decay of neutrons Pion decay with damped muons The blend of neutrinos (or antineutrinos) at the source can tell us about the production mechanism
Flavor Content at the Earth Vacuum oscillations fully developed Vacuum oscillations practically absent Cosmic NeutrinosAtmospheric Neutrinos Neutrons Pions Muons A different blend of neutrinos (and antineutrinos) arrives at the Earth
IceCube Events Topology OBSERVED EVENTS TOPOLOGIES Probability for a muon neutrino to produce a track event M. G. Aartsen et al. PRL 113, (2013)
Pions Charms Muons Neutrons Predicted Track-to-Shower Ratio The predicted flavor content at the Earth converted into the observable quantity in IceCube detector, i.e. the track-to-shower ratio is: for
Results with 3 years data Pions Charms Muons Neutrons 3 years data-set (HESE+Muons) is compatible with a cosmic origin of HEN, yet not enough statistic to discriminate the production mechanism.
Testing Unstable Neutrinos NH IH Stable States “Non radiative Neutrino decay can be tested using flavor ratios of cosmic HEN” 3 years data-set (HESE+Muons) already disfavor the decay hypothesis for both the mass hierarchies
CORE COLLAPSE SUPERNOVAE Collaboration: G.P., E. Katsavounidis, E. Coccia, C. Casentini, V. Fafone, W. Fulgione, F. Vissani, C.Vigorito, G.Testera, C. D. Ott, V. Re, K. Scholberg, M. Gromov, L. Koepke References: Proposal for data exchange among GW detectors: LIGO, Virgo and neutrinos detectors: Borexino, LVD and IceCube I. Leonor et al., Class.Quant.Grav. 27 (2010) G.P. et al., Phys.Rev.Lett. 103 (2009) Neutrinos and Gravitational Waves
Electromagnetic Strong Interaction Weak Interaction Gravity The Supernova puzzle The interplay among the known forces is so strong that we rely on very complex numerical simulations EXPLOSION MECHANISM IS STILL UNCERTAIN
Science Case Supernova “Central Engine” Neutrinos and Gravitational Waves (GW) are the only direct probes of the supernova engine. EM waves (optical/UV/X/Ga mma) : secondary information, late-time probes of engine. Red Supergiant Betelgeuse D ~ 200 pc Neutrinos and Gravitational Waves carry complementary information: Neutrinos: primarily thermodynamics GWs: primarily dynamics ->Joint observation will increase new physics learned! slide from C. Ott
Neutrinos Expectations ENERGY FLUENCE DURATION
GW expectations Amplitude: Frequency: Uncertainty on the prediction of orders of magnitude! Signals cannot be modeled. It’s very compelling to discriminate These short duration bursts of GWs From the spikes due to the Noise ENERGY DURATION
THE IDEA EARTH SN GW Det A Det B First neutrino event detected First neutrino reaching Detector B
SuperKamiokande Distance Reach Super-Kamiokande ’s recent “distant” burst search requiring two neutrino events (with energy threshold 17 MeV) within 20 seconds shows a ~18% probability of detecting a SN in M31 Requiring the coincidence with a GW trigger it is possible to lower the threshold to 8.5 MeV increasing the detection probability to the ~35% SK (2010) JOINT
STRANGE STARS Collaboration: G.P., M. Mannarelli, L. Pilo, A. Parisi References: M. Mannarelli et al., arXiv: M.Mannarelli, G.P., A.Parisi, L.Pilo, Phys.Rev. D89 (2014) 10,
Strange Stars vs Neutron Stars Strange Matter is characterized by a different equation of state (EoS) and by very different response to the stress Looking for signatures of the presence of strange matter
Charge Distribution CCSC ELECTROSPHERE Spilled Electrons z z=0 Electrons G. Pagliaroli, LNGS 19 Star Surface is electrically charge
Torsional Oscillation l=1 n=1 CCSC CFL Top view Strong EM emission
Prediction vs Observations No periodicity Radio Frequency Band High Emitted Power Short Duration (Parkes 64 meter radio telescope) Only frequencies ≥ GHz Bandwidth of 400 MHz centered at GHz 21
Non-bare Strange Star Crust of Normal Matter Torsional Oscillation
Peculiar Crust Breaking Oscillation Amplitude Strain
TOP TRAVEL DESTINATIONS 2016 High-Energy Cosmic Neutrinos Core-Collapse Supernovae Strange Stars