High Energy Physics with a Tevatron:

David Saltzberg (UCLA)

SalSA meeting

SLAC

Feb 3, 2005

Teraton:

Probing elementary particles & fields using a 500 km3-sr

UHE cosmic neutrino detector

The Impact of Cosmic Neutrino Sources on Particle Physics….the first 40 years

1. weak eigenstates ≠ mass eigenstates

2. mass ≠ 0

Every cosmic neutrino source has had major impact on particle physics:

lack of dispersion

mass of neutrino state coupling to e <~20 eV

SN1987A

Kamiokande

Homestake

Super-K

An Experimentalist’s theoretical review

“New Physics” in the Sources Topological Defects Monopoles

“New Physics” in the Cross Section Low-scale quantum gravity Extreme proton structure down to x ~10-8

Physics of the Neutrino Neutrino decay Sterile neutrinos Dirac vs. Majorana mass Instantons CPT violation Lorentz invariance Measuring the neutrino mass with the highest energy ’s

Topological Defects

Possible “relic” particles (dubbed X) due to symmetry breaking phase transitions in the early Universe: Masses at the GUT scale (MX~1025 eV).

By why don’t these decay in 10-40 sec?

- Confine in “topological defects” stable until destroyed/ annihilate

NO COSMIC ACCELERATOR NEEDED: “top-down” scenario

- X jets mesons neutrinos

- X leptons or even all neutrinos

Topological Defects

Some specific models Bhattacharjee, Hill, Schramm PRL 69, 567, (1992) Protheroe & Stanev PRL 77,3708 (1996) Sigl, Lee, Bhattacharjee, Yoshida PRD 59,043504 (1998) Barbot, Drees, Halzen, Hooper, PLB 555, 22 (2003)

Basic ideas Were attractive to circumvent GZK cutoff for UHE cosmic rays. Topological defects could be monopoles, superconducting cosmic

strings, domain walls Generally these models produce hard neutrino spectrum: ~ E-(1-1.5)

- “bottom-up” scenarios are more steeply falling: E-2 to E-4

- not ruled out by lower energy telescopes

- constrained by MeV—GeV isotropic photon fluxes

Neutrino flux vs. energy sensitive to source evolution vs. z of TD’s.

Neutrino Telescopes for Direct Monopole Detection

Monopoles: Dirac: The presence of even one

monopole explains electric charge quantization

Monopoles are typically part of GUTs Masses typically of order GUT scale but in some models Mmp could even be

as low as ~1014 eV.

Observation of monopoles would be revolutionary for HEP

Parker bound (10-15 cm-2 s-1 sr-1) c.f. UHECR>1020 eV (~10-21 cm-2 s-1 sr-1) Caveat: if monopoles catalyze proton

decay then (lack of) neutron star heating provides extremely strong limit.

Neutrino Telescopes for Direct Monopole Detection

Intergalactic magnetic fields sheets (~100 nG over 50 MPc) could accelerate monopoles to energies of ~5£1024 eV

Light monopoles would be relativistic so are candidates for radio Cherenkov detection

Parker bound (10-15 cm-2 s-1 sr-1) c.f. UHECR>1020 eV (~10-21 cm-2 s-1 sr-1) other direct MP searches, generally worse than Parker bound

Relativistic monopoles mimic particle with large charge: at least Z~68 produce EM showers along path by pair-production, photo-nuclear continuously produces shower along its path unique signature

WKW estimate F<10-18 cm-2 s-1 sr-1 for a km3 detector for 1 year. SalSA could do much better: sensitive for Mmp up to 1023 eV, far beyond production at accelerators.

Flux limit better than typical searches

Wick, Kephart, Weiler, Biermann

Neutrino interactions in SM

Early calculation McKay, Ralston, PLB 167, 103 (1986)

Most commonly used: Ghandhi et al., Astropart. Phys. 5, 81 (1996):

n p

e

e

n p

W

/E/E0.36

UHE Neutrino Cross Sectionand low-scale Quantum Gravity

Probing interactions at high CM Ecm = (2 mp E)1/2 150 TeV for E = 1019 eV

SM(+N) ~ 10-7 £ SM(p +N)

Large extra dimension models could enhance cross section Gravity could become strong at ECM=MD

Non-perturbative effects could produce KK-exitations, string excitation, pea-branes, micro-BH above ECM

Astrophysics and laboratory limits still allow n=4, MD > 10 TeV

n¸ 5 MD>1 TeV

Enhancement of UHE Neutrino Cross Section

SM

Alvarez-Muniz,Feng,Halzen,Han,Hooper PRD65, 124015 (2002)

Anchordoqui et al., PRD66, 103002 (2002)

10-34

10-32

10-30

(c

m2 )

10191017 1021

E (eV)

SM

Sample predictions for MD~1 TeV, n~6-7:

Caveat: not all energy goes into BH or excitation, and need minimum energy for classical BH formation. UHE cross sections could be up to ~100£ Standard Model

* would be invisible to UHECR interactions

Anchordoqui,Feng,Goldberg,Shapere, PRD65, 103002 (2002)

Less exotic physics with cross section

HERA tests proton structure to x~ 10-4 (only 10-2 at “high” Q2) UHE probes proton structure to x ~ 10-8

Extreme regime: More likely to scatter off of bottom sea than up/down valence. observables? Check SM with NC/CC ratio at extremely high Q2

l,

p

nucleon

xp

Ghandi, Quigg,Reno,Sarcevic

Neutrino Flavor Effects

Critical parameter for neutrino oscillations and decay is proper time, L/E. Solar neutrinos: 150,000 km/5£106 eV = 30 m/eV “SalSA” neutrinos from 4 Gpc/1017 eV = 109 m/eV

Standard model: neutrinos change flavor by oscillation $ (atmos. mixing) tan2 ~ 1.0 (maximal)

$ e (solar mixing) tan2 ~ 0.4

Evolution of ratios case 1: pion decay at source ! ! e e (e.g. GZK)

e: : 1:2:0

becomes 1:1:1 regardless of solar mixing angle case 2: if muons lose energy before they decay

e: : 0:1:0

becomes (0.5-0.7):1:1 depending on solar mixing angle

Neutrino Decay?

In SM, neutrino decays highly suppressed: low neutrino masses small phase space in “golden rule” j ! i suppressed by leptonic GIM mechanism

j ! i extremely small since magn. moment is small

SM lifetime far longer than transit time Beyond SM physics

If there lepton flavor number and lepton number are spontaneously broken symmetries, then the symmetry breaking could correspond to massless goldstone boson, majoron (J)

J couples only to neutrinos Allows relatively fast decays: ! + J or ! +J This theory is not currently favored but arguments apply to any decay

Neutrino Decay’s imprint onNeutrino flavors

Neutrino decay leaves a strong imprint on flavor ratios at Earth and is sensitive to hierarchy

SalSA opportunity is if GZK are the only neutrinos. Otherwise, lower energy neutrino telescopes (with flavor ID) have better L/E.

e::! (5-6):1:1 e::! 0:1:1

Beacom,Bell,Hooper,Pakvasa,Weiler, PRL 90,181301 (2003)Recent review: Pakvasa, Phys. Atom. Nucl., 67, 1154 (2004)

13 and CP

Allows : to deviate from 1:1

Measuring CP violation in the neutrino mixing matrix requires Ue3 (ie, sin 13) to be non-zero.

|Ue3| known to be <0.04

currently the topic of reactor and accelerator efforts

Measuring Ue3 via sin13 through reactor (disappearance) or accelerators (appearance) are the standard techniques.

13 and CP

IF neutrinos decay, then there is sensitivity to 13 and CP-violation (only if it is normal hierarchy)

0

45

90

135

180180

135

90

450

Beacom,Bell,Hooper,Pakvasa,Weiler, PRD 69, 017303 (2004).

Exotica involving decays If most massive neutrinosterile neutrino, get 2:1:1 (if normal hierarchy)

Beacom,Bell,Hooper,Pakvasa,Weiler, PRL 90,181301 (2003).

This flavor analysis assumed CPT conservation. Could get different ratios if CPT were violated Barenboim & Quigg, PRD 67, 073024 (2003).

Dirac vs. Majorana Helicity effects

- Pakvasa, hep-ph/0305317

- If Dirac, daughters of “wrong” helicity become sterile

Dirac: change ratios, Majorana: preserve ratios

Pseudo-Dirac neutrinos

- Beacom, Bell,Hooper,Learned,Pakvasa,Weiler, PRL 92, 011101 (2004)

- What if the 3 active states are nearly mass-degenerate with 3 sterile neutrinos?

- Can probe 10-18 < m2 < 10-12 eV2

Could multi-PeV and greater neutralinos (0) could be the dark matter?

Neutrino telescopes often look for annihilation neutrinos 0 + 0 ! Neutrino telescopes commonly look for

neutrinos coming from the core of Sun or Earth

Unfortunately the are absorbed in the material on their way out

get out but with <1 PeV energy

So, the answer is probably no.

Can SalSA Look for Superheavy SUSY annihilation?

0

0

0

Sun or Earth

Z Bursts &Relic neutrino mass spectroscopy

A “trick” to circumvent the GZK cutoff (Weiler ’82):

However, mCNB

could be as large as 0.3 eV

(degenerate masses, constrained by WMAP)Gelmini,Varieschi,Weiler, PRD70, 113005 (2004)

Eberle,Ringwald,Song,Weiler, PRD70 023007 (2004) E

UHECR~ 1021 eV

Next generation would be sensitive to these.

If non-degenerate, m~0.04 eV, requires 1023 eV neutrinos

GLUE and FORTE have largely ruled out necessary fluxes

Absorption dip measures mass

Time Domain Neutrino Mass Spectroscopy?

A neutrino is born as a weak eigenstate = a linear superposition mass eigenstates The proper treatment uses wave-packets for 1, 2, 3 superposition

B. Kayser, PRD 24, 110 (1981)

Packets for m1 m2 m3 so v1 v2 v3

Originally was interesting for larger mass neutrinos from SN. Over cosmological distances, packets may “decohere” and arrive at different times About 50 msec for GRB at z=1. Is the underlying process fast enough? Would be the purview of lower energy neutrino telescopes if there are sources. At

least for Teraton detectors the GZK neutrinos are expected.

Conclusions

Teraton neutrino telescopes can make probe the standard model in unique ways ~150 TeV center-of-momentum energy 108 times longer baseline for decay and oscillations