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Asia-Pacific Center for Theoretical Physics Topical Research Seminar. Astrophysical Neutrinos. Kim Siyeon Chung-Ang University 2007 / 6 / 2 at Chung-Ang University. Contents. Brief on neutrinos Astronomical sources of neutrinos Neutrino telescope and neutrino oscillation
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Asia-Pacific Center for Theoretical Physics Topical Research Seminar Astrophysical Neutrinos Kim SiyeonChung-Ang University 2007 / 6 / 2 at Chung-Ang University
Contents • Brief on neutrinos • Astronomical sources of neutrinos • Neutrino telescope and neutrino oscillation • 8-fold degeneracy in mixing parameters astrophysical neutrinos
Neutrinos • Flavors of neutrinos: na = (ne, nm, nt) • Weak interaction, -L ⊃ l-Wm+gm na • Massive neutrinos: m1nT1n1+ m2nT2n2+ m3nT3n3 • PMNS matrix: na =Uaini, ni= (n1, n2, n3) • Unitary matrix: U = R(q23)R(q13,d)R(q12) c13c12 -c13s12 s13e-id -c23s12-s23s13c12eidc23c12-s23s13s12eids23c13 s23s12-c23s13c12eid-s23c12-c23s13s12eidc23c13 astrophysical neutrinos
They oscillate. 같기道 • Evolution na(x,t) = ∑ Uamnmeipxe-iEt • Oscillating probability P( a →b, x) = ∑|Uam|2|Ubm|2 +m m’∑ Re(UamUam’Ubm’Ubm) cos(Dm2 x/2p) +m m’∑ Im(UamUam’Ubm’Ubm) sin(Dm2 x/2p) • Oscillation length L mm’ = 2p 2p/|mm2-mm’2|oscillation requires neutrinos to have both mass and non-trivial mixing. 이 맛도 아니고, 저 맛도 아니여! astrophysical neutrinos
Solar neutrinos astrophysical neutrinos
Solar neutrino deficit • The disagreement between observations of the solar neutrino flux and solar model predictions astrophysical neutrinos
Neutrino Oscillations • Solar neutrino deficit is now understood as a consequence of neutrinos oscillation. astrophysical neutrinos
Atmospheric neutrinos astrophysical neutrinos
pm nm e nmne pmnm enmne Zenith angle distribution Flavor ratio of source neutrinos astrophysical neutrinos
68% C.L. 90% C.L. 99% C.L. Atmospheric neutrino oscillation • nm→nt oscillation • SK data 1289.4 days (79.3 kt.y) • Dm2 = (1.7 – 4) x 10-3eV2 • sin22q > 0.89 astrophysical neutrinos
Astrophysical sources of neutrinos Supernova remnant Active Galaxy (optically dense, e.g. FRII) Microquasar (SS433 etc.) Black hole with mass of sun Black hole with 108 x mass of sun Crab nebula extra-galactic galactic astrophysical neutrinos
Active galaxy • A super-massive black hole lies at the center, emitting a part of energy as x-rays and gamma-rays. • Quasars, Seifert galaxies, Blazars. 2002 Oct. The X-ray jets of XTE J1550, Chandra X-ray observatory. / 2003 Nov. The most distant X-ray jet. 12bilion LY. astrophysical neutrinos
SN1987AJan.2007→↓Jan. 1997 Super nova remnant Crab nebula, M1 astrophysical neutrinos
SN1987A neutrino burst astrophysical neutrinos
Animation of Super Nova Explosionpresented by G. Raffettat SNOW 2006 astrophysical neutrinos
Main-sequence star Onion structure Helium-burning star Collapse (implosion) Hydrogen Burning Helium Burning Hydrogen Burning Stellar Collapse and Supernova Explosion Degenerate iron core: r 109 g cm-3 T 1010 K MFe 1.5 Msun RFe 8000 km astrophysical neutrinos
Newborn Neutron Star Collapse (implosion) Explosion ~ 50 km Neutrino Cooling Proto-Neutron Star r rnuc= 31014 g cm-3 T 30 MeV Stellar Collapse and Supernova Explosion astrophysical neutrinos
Newborn Neutron Star ~ 50 km Gravitational binding energy Eb 3 1053 erg 17% MSUN c2 This shows up as 99% Neutrinos 1% Kinetic energy of explosion (1% of this into cosmic rays) 0.01% Photons, outshine host galaxy Neutrino Cooling Neutrino luminosity Ln 3 1053 erg / 3 sec 3 1019LSUN While it lasts, outshines the entire visible universe Proto-Neutron Star r rnuc= 31014 g cm-3 T 30 MeV Stellar Collapse and Supernova Explosion astrophysical neutrinos
Scheme of Neutrino burstpicture by Hans-Thomas Janka, Max-Planck, Garching • Neutrinos are trapped due to elastic scattering, r (1012g/cm3) • With r(1014g/cm3), the nucleons give rise to high pressure and the sound wave travels outwards (shock wave). T increases. • The shock dissociates the Fe-nuclei. Huge amount of free protons are produced. astrophysical neutrinos
Sudden neutrino burst from regions beyond the neutrinosphere (Rn). • Delayed shock scenario is taken over prompt shock scenario. • Accretion shock: The shock wave stops and matter from outer regions falls through it toward the core. • n-reaction behind the shock: pair-annihilation: e-+e+ ↔ n+nbar neutrino-bremstrahlung: N+N → N+N+n+nbar EC/PC: ne + n → p + e- and nebar + p → n + e+ astrophysical neutrinos
The Universe within 500000 Light YearsThe Satellite Galaxies 1 pc = 105 AU1 Ly = 0.3 pc astrophysical neutrinos
Events in a detector with30 x Super-K fiducial volume,e.g. Hyper-Kamiokande 30 60 250 Detection of SN neutrinos • From the next galaxies (D~10kpc): - High statistics signal possible in several detectors. – Test SN physics and test neutrino oscillations. – SN rate is low. A few per century. • From nearby galaxies (D<10Mpc):- Only 1-2 events per SN in a megaton detector- SN rate is larger than 1 per year.- Study neutrino fluxes and spectra astrophysical neutrinos
Known galaxies with SNe Andromeda galaxy, M31, 760 kpc.SN 1885A: only SN recorded.~ 1.2 SN/century, Tammann, 1994 NGC 6946, 5.5 Mpc.Observed Supernovae: 1917A, 1939C, 1948B, 1968D, 1969P, 1980K, 2002hh, 2004et astrophysical neutrinos
LVD (400) Borexino (80) Super-Kamiokande (104) Kamland (330) SNO (800) MiniBooNE (190) Borexino (80) In brackets events for a “fiducial SN” at distance 10 kpc Amanda/IceCube Large detectors for SN neutrinos astrophysical neutrinos
Flavors of SN neutrinos Raffelt, 2001 astrophysical neutrinos
Hertzsprung-Russell diagram astrophysical neutrinos
The Twelve Brightest Stars in the Northern Hemisphere astrophysical neutrinos
Red Supergiant Betelgeuse (Oria) 130 pc (425 lyr) If Betelgeuse goes Supernova:6107 neutrino events in Super-Kamiokande Odrzywolek, Misiaszek, Kutschera, 2003 astrophysical neutrinos
Cannon Ball Model of GRB Dar, De Rujula, Plaga GRB (quasi-thermal) from 0 decay neutrinos • Core collase of massive stars: relativistic fire ball jet may penetrate stellar envelop. - Meszaros, Waxman, 2001 • Shock-accelerated protons from GRB interact with external protons indense cloud. Neutrinos with a few GeV to about 1PeV -Paolis, 2001 • ‘s extremely forward collimated - the stronger the higher their energy SN shell Cannon Balls astrophysical neutrinos
Acceleration and propagation of Neutrinos • Highest energy neutrinos are born as nm : Neutrino mixing of nm produces ne ,nm and nt fluxes in ratio of 1:2:2 after propagating astronomical distances Beacom, Bell, Hooper, Pakvasa, and Weiler, 2003 • pointing capability of neutrinos offers unique chance to identify discrete sources. astrophysical neutrinos
Cosmic rays Detection of cosmic neutrinos neutrino telescopeDetection of comic muons CAU cosmic ray detector astrophysical neutrinos
Primary particles: Protons(90%), alpha(9%), electron(1%) Solar cosmic rays: 10-100 keV, The average composition is similar to that of the Sun itself. Galactic cosmic rays: HE charged particles that enter the solar system from the outside, protons, electrons, and fully ionized nuclei of light elements. Extragalactic cosmic rays: HE particles from beyond our galaxy. E> 1015 eV. ultra-high-energy cosmic ray (UHECR): appears to have extreme kinetic energy, comparable to the GZK limit. Oh-my-god particle, E = 3x1020 Dugway, Utah, 1991(cf. God particle, Higgs)If it was a proton, its speed would have been approximately (1 - (5 × 10-24)) c. Cosmic rays. astrophysical neutrinos
IceCube: neutrino telescope O(km) long muon tracks 15 m astrophysical neutrinos
Measurement of neutrino flux • IceCube will distinguish nm, ne, nt based on the event characteristics: • nm→ m produce long muon tracksGood angular resolution, but limited energy resolution • ne → e produce EM showersGood energy resolution, poor angular momentum • nt→ t → nt produce ‘double-bang’ events at high energyOne shower when t is produced, another when it decays. astrophysical neutrinos
ντdetection technique in Volumetric detectors Usual Analysis Relies on 2-step Cascade detection : interaction jet + decay jet Interaction and Decay must occur close to sensitive volume to separate interaction and decay. Lτ =49 Eτ m/PeV τ ντ ντ km3 Primary goal: n spectra in AGN range ( 1013 - 1016 eV) astrophysical neutrinos
pmnm enmne Flavors of astrophysical neutrino sources • Flavor ratio: ( Fe : Fm : Ft ) • Neutron beam source: (1:0:0) ~ TeV. HE proton be converted to a HE neutron (p + g → n + p+). Neutrinos are produced from the neutron decays. (1:0.4:0.4) at telescope • Pion beam source: (1:2:0) ~ PeV (p+ → … → e++nm+nebar+nmbar). The four leptons share equally the energy of the pion.(1:1:1) at telescope • Muon damped source: (0:1:0)from pion decays with muon absorption. dN/dE ~E-2, eg., from GRB, ~ GeV astrophysical neutrinos
8-fold degeneracy in neutrino parameters Ambiguity due to (q13,d) Ambiguity due to sgn(Dm132) astrophysical neutrinos
Octant degeneracy with sgn(q23-p/4)in P(nm↔ne) ~sin2(2q23 ) astrophysical neutrinos
Astrophysical neutrinos as resolution of octant degeneracy • Oscillating probability over a very long travel:P( a →b, x) = ∑|Uam|2|Ubm|2 +m m’∑ Re(UamUam’Ubm’Ubm) cos(Dm2 x/2p) +m m’∑ Im(UamUam’Ubm’Ubm) sin(Dm2 x/2p) = dab - 2 m<m’∑ Re(UamUam’Ubm’Ubm) • Analysis by W. Winter, 2006 • sin2(2q23) =1, sin2(2q12) =0.83, sin2(2q13) =0.1 • No dependence on Dm2 • Expect R ≡Fm/(Fe+Ft) for astrophysical sources. Averaged out ! astrophysical neutrinos
R neutron beam = Pem / (Pee+Pet) ~ 0.26 + 0.30 q13 cos dCP, to the first order in q13 • R muon damped = Pmm / (Pme+Pmt) ~ 0.66 - 0.52 q13 cos dCP astrophysical neutrinos
R pion beam = (2Pmm +Pem) / (2Pme+Pee+2Pmt+Pet) ~ 0.50 - 0.14 q13 cos dCP • Pme~ 2q132 ± 0.09 q13 cos dCP astrophysical neutrinos
Remarks • More resolution to be suggested. Hwang and Siyeon • Complementary to determine the neutrino parameters in three different types of experiments. • Long-base line appearance neutrino oscillation • Reactor neutrino disappearance oscillation • Neutrino telescope with high energy sources. • Astrophysical neutrinos are direct messenger of astronomical events. (better than protons) • We will be full-equipped with Chandra X-ray, IceCube, Antares, WMAP, etc. astrophysical neutrinos