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David Hardtke UC Berkeley. Exotic Physics with IceCube. Nuclear Physics. nuclearites. monopole. Low-x Partons. Supersymmetry stau pairs Q-balls WIMPS. Extra-Dimensions Mini black-holes TeV gravity. IceCube. AMANDA. South Pole. Skiway. Dome (old station ). road to work.
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David Hardtke UC Berkeley Exotic Physics with IceCube Nuclear Physics nuclearites monopole Low-x Partons • Supersymmetry • stau pairs • Q-balls • WIMPS • Extra-Dimensions • Mini black-holes • TeV gravity
IceCube AMANDA South Pole Skiway Dome (old station) road to work “Summer camp” Amundsen-Scott South Pole station http://icecube.wisc.edu
Optical properties of S.P. Ice -- Worth the trip! Scattering Absorption bubbles ice dust dust Measurements: in-situ light sources atmospheric muons Dust Logger optical WATER parameters: labs ~ 50 m @ 400 nm lsca ~ 200 m @ 400 nm Average optical ice parameters: labs ~ 110 m @ 400 nm lsca ~ 20 m @ 400 nm
~ 1 km3 size driven by Waxman-Bahcall neutrino flux predictions • AMANDA is a densely packed sub-array • IceTop surface array for cosmic ray /composition/ calibration studies 50 1450 35,600 Age of Ice (years) Depth (meters) 2450 96,800
AMANDA vs. IceCube IceCube is both larger and technologically superior
Digital Optical Module Digitized Waveform (400 ns) Each DOM is an autonomous data collection unit Measure arrival time of every photon Power consumption: 3.5 W Digitize at 300 Mhz, 400 ns 40 MHz, 6.4 µs Send all data to surface over copper Cable: power, data, time stamping Two sensors/twisted pair. Flasherboard with 12 LEDs Local HV 25 cm Hamamtsu PMT Main board PMT base LED flasher board 12 LEDs 33 cm Benthos Sphere
Time Calibration for 76 DOMs In-ice DOMs Time IceTop IceTop Clock stability: 10-10 ≈ 0.1 nsec / sec Synchronized to GPS time every ≈5 sec at a precision rms = 2 nsec (Rapcal calibrations)
Timing stability verified with cosmic ray muons Time difference between adjacent DOMs was measured for down-going muons (150Hz) Time difference stable as function of time Fast, easy, reconstruction independent way to verify timing Independently verified using time residuals Timing stable to ~2ns (over the course of the year)
Construction Status: Feb 2006 AMANDA runway SPASE String + Icetop installed String 21 IceTop tanks installed 125 m New Station 1 string + 8 tanks deployed Jan. 2005 8 strings + 24 tanks deployed in Dec/Jan of 05/06 604 DOMs (survival rate 99% !!)
Exotic Signals in IceCube • Standard signals • Neutrino induced muons, cascades, lollipops, … • Cosmic-ray induced muons • Non-standard signals • Superbright Cerenkov radiators (monopoles) • Non-relativistic cosmic rays (Strangelets, Q-balls, GUT monopoles) • Unique showers (lepton free showers, …) • New particles (slepton pairs, …) • New Particle Physics using atmospheric and extraterrestrial neutrino beam: • Cross-section deviations at high energies • Low-x physics in proton/nucleus (charm and prompt leptons in air showers) • Lorentz Invariance Violation
Monopoles • Much brighter than bare • Magnetic Charge g = (1/2)e • Cerenkov (n·g)2~ 8300 dN/dmuon • Ionization ~ 4700 (dE/dx)muon • Utilize dynamic range of IceCube 1 PeV Muon 1 PeV Monopole
Monopoles Limits and Future • Published Limits • IceCube will be large improvement • Bigger effective area • No saturation • Topological in-ice trigger • Lower velocity monopoles -- radio-luminescence? • Nucleon-decay catalyzing monopoles (Rubakov-Callan mechanism) • Will push limit towards ~10-19 cm-2 s-1 sr-1
Nuclearites • At very large quark (baryon) number, strange quark matter with u≈d≈s may be absolutely stable • Interior of neutron stars • Nuggets produced in neutron star collisions or early universe • Characterized by Z/A << 1/2 • Large mass nuclearites have nuclear densities (≈0.15 GeV/fm3) but atomic dimensions (R>1 A) • Can’t be all of Dark Matter (recycled baryons)
De Rujula - Glashow Mechanism R > 1 A • Macroscopically large (atomic dimension) massive particles induce expanding cylindrical thermal shock wave Blackbody Radiation • For atomic dimension objects at virial velocities, T can reach several thousand Kelvin • Total Energy Loss: • Energy in visible photons:
Q-ball detection • SENS (Supersymmetric Electrically Neutral Soliton) • Q-ball catalyzes nucleon decay producing pions • Similar to Rubakov monopoles, but larger cross-sections • 100 GeV g-1 cm2 • ~1 TeV/s for =10-3 • SECS (Supersymmetric Electrically Charged Soliton) • dE/dx ≈ 100 GeV/cm, but no Cerenkov light • Glashow-De Rujula mechanism may work for very large MQ • Mica Limits will always be superior to modern detectors
Physics Potential (Slowly Moving Particles) DM = 0.3 GeV/cm3 Note: Lower mass limit depends on particle type/cross-section assumption
Comments on Supersymmetry, TeV gravity, micro black holes • Upward “muon” pairs (actually supersymmetric staus) • Albuquerque talk • At very high velocity, stau will travel finite distance • Almost no physics background • Challenge is two-track separation and downgoing muon bundles -- feasibility uncertain • Lepton-Free showers (TeV scale gravity) • Illana Talk • Multiple elastic neutrino interactions (multi-bang events) • No attempts at simulations yet • Micro black holes (Kowalski talk) • Cross-section deviation at UHE -- measure via angular distribution/energy spectrum of UHE neutrino events • Energy scale only reached by extra-terrestrial neutrinos • LHC may rule out large extra dimensions before we find the extra-terrestrial neutrino beam
Conclusions • km3 size necessary for neutrino astronomy improved searches for exotic physics • IceCube improves on AMANDA in both size and technology • Larger dynamic range/full waveform recording • More flexible triggering/online filtering • Will set new limits on: • Monopoles • Slowly moving massive particles (Q-balls, nuclearites) • Physics beyond the standard model • WIMPS David Hardtke -- University of California, Berkeley