GZK III: A Visit to the Zoo

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GZK III A Visit to the Zoo

• How I protect my independence from various
  proposals

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recall

• Something (1) penetrates CMB,(2) arrives in air
  showers, (3) reported E gt 1019 eV, (4) shows
  angular correlations

• YOUR probability
• of something is for YOU to decide with help
  from statistics.

?????
P(GZK new physics) P(new physics)
P(new physics GZK)P(GZK)
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The Physicists Gambit

• P(new physics GZK)
• P(GZK new physics) P(new physics)

P(GZK)
?????
????????
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What do we want ?

• We want to discover stuff!
• Plenty of people have discovered nothing
• Do you think 50 is good odds?
  . ... Is 10 good odds?

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If you Are in Physics, You Already Paid the
Priceof Assuming New Physics Could Be
Found.P(new) finite.Right?
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??????????
?
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try to get morethings explainedthanthe number
of newassumptionsyou made
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Nuclei
ANIMAL 1

• 3o

Stecker
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Nuclei

• They exist
• Even harder to accelerate up
• Fall apart quickly in 30
• Super-GZK, angular correlations ? no way.

• Its something to do. Does it turn you on?

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Strangelets?
?dsudsuds

• They dont exist --
• so I thought.
• Why accelerate chunks?
• Decay to neutral
• Stranglet CMB

• Testable show me the strangelet

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Everything Else, (e. e.) Animal 2 Top Down Models

• Cosmic strings, defects, etc.
• Freedom to use fields unconstrained by particle
  physics
• Put them all over, invisibly, and decay at any
  rate you want.
• And any mass wanted

Bondi déjà vu all over again

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Historical Fact

• Heavy things can over-close the Universe
• They ought to annihilate away
• But s lt 1/M2, from unitarity.
• Then if too heavy, they freeze out excess
  density. hence bounds lt TeV were long accepted

• Herald Tribune
• TOP DOWN MODELS GET SPECIAL VARIANCE

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well-cited, incredibly incredibly detailed

• If no particle physics in final decay products,
  then nothing to do
• If particle physics in decay products, then
• ???????????g/P gtgt1, which was not planned

• Angular auto-correlations, correlations with
  AGN?
• A neutrino source?

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My RuleIf it cant be ruled out,its not
Science

• Top-Down people need
• to develop ways to rule out their own models
  model independently

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e.e. topic 3 Z-bursts

• Annihilate to Z0

n n n
n
n
n
n n
n
n
v
n
n
50/cm3
Weiler Fargione
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Z0 exists !

• mn????eV will suffice.
• MZ2 2 mn? En?
• En?????????????eV /(mn????? eV)
• Many gs a prediction
• Resonance tall but narrow,
• overall rate low
• Fix with flux

• Needs about 1000-100000 more neutrinos than
  conventional in flux, in target clustering, or
  both.

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I personally think theflux calculations are not
a basis of decision.( P(correct social
accepted ) is not one of my terms. )Plus,
neutrinosCANcluster
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Z-burstseem to be a good model,just lacking
asecond testable signal
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e.e. topic 3 black holes
?

• s? p rs2 is conventional
• rs Schwartzchild radius for M2 s
  . cm energy2
• much work remains to be done

BH
Extra dims, Mgt TeV
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a healthybusiness in setting limits

• But read Voloshin. The quantum amplitude
• to form a coherent black hole cannot possibly be
  as big as the classical calculations imposing
  coherence.

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e. e. animal Lorentz Violation

• Fast free charge makes Cherenkov radiation
• in vacuum, vgtcm

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.and fast gs spontaneously convert to pairs
?????????? ?????????????
tMIN
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Early excitement

• ...continued excitement
• maybe somebody knows what else there is to do

• and not-so-much crisp predictability for the
  GZK problem, e.g. angular stuff

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Magnetic Monopoles

• Everyones favorite particle
• .eg/hc nh/2, mod t
• Strongly interacting
• Strongly steered and accelerated
• Mass unknown, large
• unseen

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e.e. M. M. ?

• Bremsstrahlung losses small, heavy
• Observable large signal, AMANDA, RICE (in
  progress)
• Progressive

Wick, Weiler, Biermann
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e.e. Neutrinos ? Already did that. How to
MEASURE them?
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RICE
????????? Cherenkov Experiment
Kansas University, Bartol Research
Institute, University of Canturbury, Christchurch
NZ, MIT
??3
???
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RICE background sheet

• Cold ice is 1 km transparent to radio waves
• There is plenty of ice at South Pole
• n -gt e shower makes lots of radio
• E field \sim energy, power \sim energy2
• Best method known, E gt PeV
• Not just planned, running

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Coherent Cherenkov Radiation
????
ANTENNAS! 200 MHz
ICE
?????
??
Method is a new technology, very well suited
to EgtgtPeV
??????
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Beautifully REDUNDANTdetection scheme

• Each event detected by 4, 5, 6 antennas
• 4 suffice to get vertex in 3 DIMS !
• OVERdetermined events are real events
• ALSO fit Cherenkov cone SEPARATELY

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and we are using matched filter correlations of
our own

• imaginary parts (blue) and real part (red) of
  antenna impedance

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RICE...Limits

• ???? Limit

?????????
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And Now, for something really different
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Photon torpedoes
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Exercise solved
Bessels equation !
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What this thing is.

• In other words,
• THESE ARE THE FIELDS of a UNIFORMLY MOVING CHARGE

• Cherenkov radiation,
• boosted back into the frame vlt c
• Improper boost turns J0 into K0 Bessel
• Very weird and singular as xT -gt0

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What LPM Forgot
Q
E
Actually, Ter-Mikaelian did not forget e??, but
used the atomic physics regime e?? 1 - wp2/w2.

We need sTOT (g p) at UHE
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e. e. LPM?
P

• Literature of Landau, Pomeranchuk, Migdal
• Concept of coherence length.

R1
R2
l v Dt
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Coherenceadd in phase
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What is not really explained
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Coherence length
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Result UHE bremss emissions are coherent over
many many interactions

• even if you might think that the wavelength of a
  gamma ray is far too small for interference

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Multiple scattering jitter during the
bremsstrahlung
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Yielding a factor w1/2
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???? changes thespectrum to a new power
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Radiative vs direct losses

• Radiative losses bremsstrahlung, need an
  acceleration.
• LPM damps them.
• Direct losses exist at constant velocity. LPM
  overlooked.
• Direct losses gt gt radiative losses

• LPM quenched

..WE claim
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LPM in AIRES code for air showers
Everyone accepts LPMsomeone ought to check it
out

• Cillis et al (AIRES) PRD 1999

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There is anerror inhigh energyelectromagnetic
showercodes
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Size of effect depends on sTOT(gA)for
E????????????
sTOT Donnachi Landshoff
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While still in progress, weve wondered about
AGASAshower evolution and energy calibration

• Hadronic photoproduction produces larger
  transverse momenta than usually considered, a
  pause for doubt on their calibration method

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Lets not complain about AGASA,lets find
somethingto do!
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Does fixing a mistake in relativistic
electrodynamicsdone for 50 years countas new
physics?

• yes

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Energy, SchmenergyAre there angular
correlations?
???????????????????????
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Its the ??????? variable!
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GZK and UHE Neutrinos have room for new physics,
one way or the other
The tremendous scope of the problem of the
highest energy cosmic rays has hardly been
appreciated.
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e.e. GRB Connection, do we really need a model?
HETE
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GRB seen in downtown Tokyo
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CAN YOU IMAGINEthe excitement of GRB
Razzaque, Meszaros, Waxman astro-ph 2003
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g-normalized Flux

• Kalashev, Kuzmin, Semikoz, Sigl
• PRD 2002

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Exercise
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So what is RELIABLY known about n flux?

• upper limits