ect*, october 7 2004 tom weiler, vanderbilt university high-energy neutrino astrophysics tom weiler...

ECT*, October 7 2004Tom Weiler, Vanderbilt University

High-Energy Neutrino Astrophysics

Tom Weiler

Vanderbilt University

Neutrinos and the Early Universe”, Trento ECT* Workshop,

October 4-8 2004


Cosmic Photo- Proto-Spectra

Rad

io

CM

B

Vis

ible

-ra

ys

CERN/Fermilab

x-ra

ysUV

IRCosmic-rays

TeV

-w

all

(after Ressell & Turner ‘90)

hadron wall?

no wall a’tall

sunSN87a NeutrinoIncognito


1991 Fly’s Eye reports 3x1020 eV, with proton-like profile;

Akeno/AGASA Xpt begins

mid-90sDUMAND taken off life-support; Baikal continues

90s SuperK neutrinos from the sun (directional astro)

1996 AGASA reports event clustering within 2.50 ang. res’n

and: F(E 1020 eV) ~ 1/km2/century,

with shower diameter ~ 5km, N(e) ~ 1011

2000 20 events at and above 1020 eV

2001 HiRes withdraws 7 events; AGASA adds 6 (from z > 45o);

And the controversy has begun!

Importantly, Auger gets first “light”

2002 AMANDA pushes to 1014 eV thru-Earth neutrinos

2005 Auger Observatory data expected

2008 Extreme Universe Space Observatory (EUSO) ?


CR Spectrum above a TeV

from Tom Gaisser

VLHC(100 TeV)2


Highest Energy Event

The CR record energy is 3x1020 eV (0.3 ZeV). Found by Fly’s Eye a decade ago (they got lucky!). This is truly a macroscopic energy: 3x1020 eV = 50 Joules equivalent to a Roger Clemens fastball,

a Tiger Woods tee shot,a Pete Sampras tennis serve,Or a speeding bullet.

(Also to 12 Calories, which heats a gram of water by 12oC)


3 x1020 eV = macroscopic 50 Joules

Clemens does this with 1027 nucleons;Nature does this with one nucleon, 1027 times more efficient !


Fly’s Eye 3x1020 eV event (1992)

100 billion e+e- pairs at xmax ~ 800 g/cm2

This longitudinal profile is consistent with a primary proton, but not with a primary photon; Disfavors “local” top-down sources such as massive Particle DK, topo-defects,Z-bursts, etc.


EE Neutrinos are youngLiberated at T=Mev, t= 1 sec

Depends on energy (Lorentz boost)

Consider a 1020 eV neutrino.

Lorentz factor = 1021 for m = 0.1 eV.

Age of Uni is 1018 sec,

But age of is 1018/1021 sec = 1 millisecond !

And it doesn’t even see the stream of radiation rushing past it – untouched !


Size mattersEUSO ~ 300 x AGASA ~ 10 x AugerEUSO (Instantaneous) ~3000 x AGASA ~ 100 x Auger

Exposure

1

10

100

1000

10000

Year

Expo

sure AGASA

HiResAugerEUSO


Extreme Universe Space Observatory

2009 EUSO onboard the ISS (Or Not!)

2012 Hundredth anniversary of Hess

– EUSO finishes three-year data-taking

http://www.esa.int/export/esaHS/ESA6NE0VMOC_iss_3.html


“clear moonless nights”

Blackout_14aug03.jpeg

Or New York State power blackout


Orbiting Wide-angle Lens (OWL)

3000 events/year above 1020eV

and UHE Neutrinos!


HAS event rate is small

e.g. FCR at 1020 eV implies 10-2 events/yr;


AGASA Spectrum: EeV to ZeV

AGASA, July 2002


Greisen-Zatsepin-Kuzmin and the Cosmic-Ray Wall

-resonance

multi-pions

Photo-pion production off CMB

p+cmb p/n+


HiRes vs. AGASA UHE spectrum

discovery

opportunity

GZK recovery ?Z-burst uncovery ?

FlysEye event goes here

EUSO reach x 103 better


AGASA hot-spots -- Data

red: E > 4 1019 eVgreen: E > 1020 eV

Cluster Component~ E -1.8±0.5

Neutrinos will point better


AGASA hot-spots -- numbersWithin 2.5 degree circles,AGASA identifies six doublet, one triplet,Out of 57 events;

Opening the angle to just 2.6 degrees,AGASA identifies seven doublets, two triplets;

Haverah Park contributes two more paired events in AGASA directions.

NOT corroborated by HiRes.

Source number ~ N12/2N2 ~ 270 to 50%,

weighting with GZK suppression, ~ 10-5 /Mpc3for source density


Berezinsky et al Xgal proton fluxMass-composition data (HiRes 2002)

Xgal proton dominance begins at 1018 eV, not 1019 eV !F ~ 50 x Waxman-Bahcall AMANDA/RICE/EAS-sensitive !!

(AGHW, to appear)

Theory threshold for p2.7Kpe+e- and data (knee) are at 1017.6 eV.


AMANDA to 100 TeV


AMANDA/IceCube event


Xgal proton fit huge flux

is pion energy/CR energy at source (1 for WB “limit”);z is cosmic evolution factor, 0.6 (no) to 3.0 (SFR)

WB fluxes

low Xgal dominance flux,with no evolution

AGHW, hep-ph/04010003


Neutrinos versus Cosmic-Rays and Photons

s come from central engines

- near Rs of massive BHs

- even from dense “hidden” sources

cf. s vs. s from the sun

s not affected by cosmic radiation(except for annihilation resonance)

s not bent by magnetic fields- enables neutrino astronomy

Also, besides Energy and Direction, ’s carry flavor


diagnostic of astro-engines:pp vs. p

The process e+e-- W-- is resonant at 6.4 PeV;

IceCube will have flavor ID, and E/E of 25%,and so can measure On-Res/Off-Res ratio.

pp make nearly equal

::e:e = 2:2:1:1 flavor democracy, e = 1/6 total

p via + make + e = 1:1:1 (no e) e = 1/15 total

IceCube can resolve this (AGHW, ArXiv this week)


Flavor ratio Topology ratio Map

Beacom, Bell, Hooper, Pakvasa, TJW, 2003


The cosmic flavor-mixing theorem

If theta32 is maximal (it is),And if Re(Ue3) is minimal (it is),

Then and equilibrate;

Further, if initial e flux is 1/3

(as from pion-muon decay chain),Then all three flavors equilibrate. e:: = 1 : 1 : 1 at Earth


Democracy Broken:

1. decay (15 minutes of fame)

2. Vacuum resonance(MaVaNs, LIV vector)

3. Pseudo-Dirac oscillations

4. Source dynamics (w/ Farzan)


Neutrino Decay -- Models, Signatures, and Reach


“Essentially Guaranteed” High-Energy Galactic Neutrino Flux

cn = 10 kpc (En / EeV)and

E/ En ~ Q / mn ~ 0.8 x 10-3

E ~ PeV, for En ~ EeV


“More Guaranteed”Icecube atmos background in 1o circle is just 1.5events/yr, 3.5 events offers 95% CL detection in 1 yr;

Calculated signal is 4 /yr and 16 e+ showers/yr.

Conclude that in a few years, IceCube attains 5discovery sensitivity for Fe n e Providing “smoking ice” for GP neutron hypothesis.

Comparing to “guaranteed” cosmogenic flux, Galactic beam (here) is higher !

ect*, october 7 2004 tom weiler, vanderbilt university high-energy neutrino astrophysics tom weiler...

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