Lecture II (continued) Anisotropy and Source Counts

Transcription

1 Lecture II (continued) Anisotropy and Source Counts

2 Exotica - Zoo events Topological defects from early Uni phase transtions (e.g., textures, magnetic monopoles,...) Super-Massive Heavy Particles (e.g., Wimpzillas, Mirror-Matter, See-saw masses, X&Y GUT bosons, cryptons,...) SUSY-rays (e.g., LSP, gluino-hadrons,...)

3 Magnetic Monopoles Expect (a) directions correlated with Galactic B field (spiral arm) (b) weak penetrating air-shower (c) strong Cherenkov signal in IceCube

4 Lecture III - Neutrino Astrophysics

5 Neutrino-rays versus Cosmic-Rays and Photons νs come from central engines - near R s of massive BHs - even from dense hidden sources cf. νs vs. γs from the sun νs not affected by cosmic radiation (except for annihilation resonance) νs not bent by magnetic fields - enables neutrino astronomy Also, besides Energy and Direction, ν s carry Flavor

6 Neutrinos are there, but hard to detect Existence of Xgal neutrinos inferred from CR spectrum, up to ev, and similarly, Galactic up to ev, Need gigaton (km 3 ) mass (volume) for TeV to PeV detection [e.g. IceCube Xpt] but a teraton of mass at ev SPACE-BASED [e.g. EUSO Xpt]

7 Model ν fluxes (Protheroe review 1996) atmosphere AGN pγ Ism GRB GZK GeV SMPs TDs M GUT

8 HiRes vs. AGASA UHE spectrum FlysEye event goes here discovery opportunity GZK recovery? Z-burst uncovery? EUSO reach x 10 3 better

9 AMANDA, RICE, Anita, IceCube, AURA, ARIANNA: Antarctic Cap = Antartic Trap

10 Neutrino cross-section measurement Neutrinos at ev probe the structure of the nucleon at unprecedented small-x values ; Provides new QCD information CM energy at HERA is 0.3 TeV; while at E ν ~ ev, Nature gives us E cm ~ PeV! And so probes new thresholds, e.g. SUSY, X-Dimensions, TeV-Scale Gravity, EW Instantons (NonPert. EW),

11 σ νν can be big, or small-ish Large extra dimensions Std. model Anchordoqui et al. Astro-ph/ GZK ν Also Kansans; Chicagoans; etc

12 Cross-section corresponds to MFP which matches shown chord length Earth Absorption versus Neutrino Cross-Section

13 Upward and Horizontal Air-shower Rates Versus Neutrino Cross-section (=> Can t Lose Theorem) HAS ν τ ν e UAS Kusenko, TJW, PRL2002

14 Cosmic Neutrino Flavor Physics Besides energy and direction, cosmic quanta carry intrinsic information. For cosmic-rays, it is A and Z; For photons, it is spin polarization; For neutrinos, it is flavor: electron-neutrino (which showers) muon neutrino (whose CC tracks) tau neutrino (which showers below a PeV, tracks above) Moreover, the flavors mix in a calculable/known way, which means the flavors oscillate in an L/E-dependent way, enabling: Neutrino Interferometry over Cosmic baselines!!

15 Flavor ID (windows) at IceCube Neutrino flavor T. DeYoung ν τ double full flavor bang*** ID ν e ν e (supernovæ) showers vs. tracks ν µ Log(ENERGY/eV)

16 The cosmic ν flavor-mixing theorem If theta 32 is maximal (it is), And if Re(U e3 ) is minimal (it is), Then ν µ and ν τ equilibrate; Further, if initial ν e flux is 1/3 (as from pion-muon decay chain), Then all three flavors equilibrate. (E.g., for pion source, get) ν e :ν µ :ν τ = 1 : 1 : 1 at Earth

17 Muon-damped (or, Incomplete) pion decay Predict change in cosmic flavor ratio with energy: From complete pi-decay chain, 1:1:1 at Earth, To partial pi-decay chain (~ pure ν µ beam), 4:7:7 at Earth; Diagnostic for ambient density: decay mfp vs. interaction mfp.

18 Democracy Broken: Galactic β-beam Muon-damped pion decay Source dynamics (pp vs, p-gamma) ν decay (15 minutes of fame) Vacuum resonance (MaVaNs, LIV vector) Pseudo-Dirac ν oscillations

19 Cosmic decoherence of the neutrino-mixing matrix R(theta32) R(theta13*) R(theta21) x MajoranaPhases ν 1 ν 2 ν 3 νe TB ν m ν t e.g., ν e = 2/3 ν 1 + 1/3 ν 2 ν e : ν µ : ν τ = 5:2:2

20 From (initial) flavor to (propagating) mass to (detected) flavor again: ν e ν m ν t P = ν e ν m ν t

21 Neutrino Flavor Ratios for various Astro processes 1:2:0

22 Galactic β-beam also offers excellent opportunity to improve limits (by up to ) or discover democracy-restoration due to QG Foam no-hair on virtual Black Holes 1:1:1 flavor equilibrium Anchordoqui, Gonzalez-Garcia, Goldberg, Halzen, Sarkar, TJW, [hep-ph/ ] 22

23 ν diagnostic of cosmic pion-engines: pp π vs. The process ν e +e -- W -- is resonant at 6.4 PeV; pp make nearly equal π + π, with P π /P CR ~ 0.6 ν µ :ν µ :ν e :ν e = 2:2:1:1 flavor democracy, ν e = 1/6 total pγ via Δ + make π + (per two π 0 ), with P π /P CR ~ 0.25 ν µ :ν µ :ν e = 1:1:1 (no ν e ) ν e = 1/15 total IceCube will have flavor ID, and ΔE/E of 25%, and so can measure On-Res/Off-Res ratio Ans resolve this (AGHW, hep-ph/ )

24 ν decay (via majoron emission) P(survive)= e t/ τ = e (L/E)(m/ τ 0 ) Beacom, Bell, Hooper, Pakvasa, TJW, PRL2003

25 Pseudo-Dirac Neutrinos Pseudo-Dirac Neutrinos, a Challenge for Neutrino Telescopes John F. Beacom, 1 Nicole F. Bell, 1, 2 Dan Hooper, 3 John G. Learned, 4, 2 Sandip Pakvasa, 4, 2 and Thomas J. Weiler 5, 2 arxiv:he Text the only way to reveal their existence. The generic mass matrix in the ( ν L, (ν R ) C) basis is ( ) ml m D. (1) m D m R A Dirac neutrino corresponds to the case where m L = m R = 0, and may be thought of as the limit of two degenerate Majorana neutrinos with opposite CP parity. Alternatively, we may form a pseudo-dirac neutrino [1, 2] by the addition of tiny Majorana mass terms m L, m R m D, which have the effect of splitting the Dirac neutrino into a pair of almost degenerate Majorana neutrinos, each with mass m D. The mixing angle between the active and sterile states is very close to maximal, tan(2θ) = 2m D /(m R m L ) 1, and the mass-squared difference is δm 2 2m D (m L + m R ). For three generations, the mass spectrum is shown in Fig. 1. The mirror model can produce a very similar mass spectrum [3, 4]. The current theoretical prejudice is for the right- m 3 + m 3 -- m 2 + m 2 -- m 1 + m 1 -- atmospheric solar } } }! 3a,! 3s! 2a,! 2s! 1a,! 1s FIG. 1: The neutrino mass spectrum, showing the usual solar and atmospheric mass differences, as well as the pseudo-dirac splittings in each generation (though shown as equal, we assume they are independent). The active and sterile components of each pseudo-dirac pair are ν ja and ν js, and are maximal mixtures of the mass eigenstates ν + j and ν j. Neither the ordering of the active neutrino hierarchy, nor the signs of the pseudo-dirac splittings, has any effect on our discussion.

26 Z-Bursts/Dips Seeking the CνB at Extreme Energy

27 Z-Dips/Bursts TJW, 1982; Revival 1997 (Fargion, Mele, Salis; TJW) 50 Mpc

28 Resonant Neutrino Annihilation Mean-Free-Path Fig from Fargion, Mele, Salis λ=(n ν σ ν ) 1 = 40 D H /h 70 (neglecting higher densities at earlier times)

29 Escher s Angels and Devils Looking back, n ν ~(1+z) 3, And so the absorption is greatly enhanced for ν s from high-z sources

30 Neutrino mass-spectroscopy: absorption (Z-dips) and emission (Z-bursts)

31 BB: Neutrino Decoupling, Temperature, Density

32 The (challenging) Z-burst energy With Cosmic Structure Formation restricting neutrino masses to less than ev, have Z-burst energies > ev. The whole shebangbang depends on F ν (E ν > ev)!! (Here enters GLUE, FORTE, ANITA, AURA, ARIANNA,...)

33 ν-mass spectroscopy z max =2, 5, 20 (top to bottom), n-α=2 Eberle, Ringwald, Song, TJW, 2004 The whole shebangbang depends on F ν (E ν > ev)!!

34 Summary I. Cosmic Ray physics: Now entering a golden era of ev exploration. At this energy, protons point, enabling CR astronomy. In addition, particle physics thresholds may have been breached, and there may be a Cosmic Zoo awaiting discovery. II. Neutrinos from the Cosmos: Next one to ten years will be critical, and, the deities/gods willing, most fruitful! Neutrino Flavor will play a big role.