ucl xmas 2006 : dec 18 1 from the tevatron to the zevatron mark lancaster simon bevan, amy connolly,...

UCL Xmas 2006 : Dec 18 1

From the Tevatron to the ZevatronMark Lancaster

Simon Bevan, Amy Connolly, Ryan Nichol, Dave Waters


Open Cosmic Ray Questions

- what is their primary composition : protons or heavier- what / where is their origin for E > 1020 eV

E (eV)

Want to probe 1020 eV region

- inconsistent CR data here- s ~ 400 TeV (>> LHC)

Best probes of this region are


Present / Planned UHE v Experiments

Optical : ICECUBE (ice), BAIKAL(ice), ANTARES (water) - limited energy reach to 1015-17 eV (attenuation length, cost) - limited information from high energy atmospheric neutrinos - no guaranteed source of point(ing) / direct

ATM (CR + N(atm))

ATM

Direct


Beyond IceCube

E > 1017 eV only possible via radio/acoustic detection via Askaryan effect.

In the 1020 region: - guaranteed flux of UHE from GZK process - pointing information (primary p not bent or are from point source)

LHC

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 log10[E (eV)]

GUT

PhotonsHESS

1 per km2/century/sr

AUGER

Protons

ICECUBE ANITA/ARIANNA

Neutrinos

GZK

Su

nS

N19

87


Beyond IceCube : getting to physics

Rates in the 1020 region are low. Need > 1000 km3 detectors & a plan

1. establish Askaryan effect & optimise simulations- 1979 (acoustic)- 2001-5 (radio)

2. pioneering radio experiments (Moon, Greenland, Antartica, satellites) with limits- FORTE/GLUE/RICE/ANITA-lite : radio Askaryan : 2001-2005

3. R&D acoustic experiments- ACORNE, SAUND, SPATS : 2003-2008

4. discovery radio experiments- ANITA / LOFAR (?) : 2006-2010

5. physics experiments : large volume fixed arrays with radio+acoustic- ARIANNA, KM3(?), AURA : 2010-2020


Acoustic Askaryan

32 GeV p at BNL in 1979 into water


Radio Askaryan Effect Established

Verified P E2

2005

e- excess moves v > cmedia


Existing Limits

FORTE

GLUERICE

AMANDA

GZK p

GZK Fe

TD

ANITA-lite

Z-burst

Need improvement offactor ~ 100 in radio to “discover”GZK neutrinos

And then further factor of 10to do physics.

Already some extreme beyondSM models (TDs) have beenexcluded

Acoustic still in R&D mode

AcousticSAUND

optical

LHC


ANITA experiment

Sees earth skimming neutrinos via coherent Cerenkov radio pulse

Views1.5 x 106 km3

of ice(cf IceCube 1km3)


ANITA experiment

- took off on Friday at 1am.


ANITA: Where is it now


ANITA: Planned UCL Role

Improve sensitivity by factor of 2 for next (2008/9) flight

- improve trigger : lower threshold 1018 1017 eV

- improve DAQ / firmware : lower deadtime

- improve the simulation

And hence hopefully “discover” the GZK neutrinos


Towards a Physics Detector : ARIANNA

Ice shelf

Reflected Ray

Direct Ray

Array of 100x100 antennas atop the Ross Ice Shelf looking down– No deep holes (cost effective)– Build on ANITA DAQ & Simulation experience


ARIANNA Status

Feasibility studies just started : attenuation measurements etc

UCL: Simulation Electronics Commoditisation


ARIANNA Reality


LOFAR

77 fields in Holland each with 96 two-band radio antenna.

Expect 2 fields in UK (£700k)

+ 20 in rest of EU.

Truly digital radio telescope with no moving parts


LOFAR

- Each station sending data at 3 Gb/sec- Central hub (IBM blue-gene : 34 Tflops, 1Pb memory) correlates data at 800Gb/sec effective dish size ~ 100 km- Sees whole sky at once

UHE

Radio shower

MOON

Operating at low frequency wheresignal is small but compensatedby wide Cerenkov cone

GUT


ACORNE Status

Acoustic Pressure Waves

Hydrophone Array

Work at UCL- developing reconstruction algorithms to track position of hydrophones- code to extract flux UHE limit from data


ACORNE

Simulated events-Track position of hydrophones with background events.- Combinatorics : problematic in finding the true 2 minima


ACORNE : Acoustic Pulse Simulation

Profile of acoustic pulse

- differences between published (SAUND) curves & more recent simulations (ACORNE & ANTARES)


If observed then what :

A single UHE will be interesting to astro-physicists

NASA SWIFT X-ray satellite AGN map


N Cross Section at s = 400 TeV

Upper SM limit

Vary extra-dimensionsARIANNA

50% precision: 2 yearsLHCx ~ 10-5


phenomenology over very large baselines

Large L/E should give ~ flavour isotropy at earth

LV can circumvent GZK cut-offUsual kinematic constraints altered. tend to be depleted

Neutrino Decay

e

GZK GPc

No new physics

Lorentz Violation


Wimpzillas, Topological Defects

String Resonance increasing(N) for E > 1018 eV

T [log10(eV)]

25

23Grand-unified-theory (GUT) phase transition ??

12

10Electro-weak phase transitions: known

8 Quark-hadron phase transition: known6 Nucleosynthesis phase transition: known

Gravitons & super-massive relic (“WimpZilla”) particles form near GUT phase

Expect + flux from cascade decay of such particles

SM


Conclusions

If there is anything astronomically odd

or new particle physics > 10 TeV

then UHE offer an opportunity to see it

ucl xmas 2006 : dec 18 1 from the tevatron to the zevatron mark lancaster simon bevan, amy connolly,...

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