0000000000344836
AUTHOR
C.p. Burgess
First year performance of the IceCube neutrino telescope
The first sensors of the IceCube neutrino observatory were deployed at the South Pole during the austral summer of 2004-2005 and have been producing data since February 2005. One string of 60 sensors buried in the ice and a surface array of eight ice Cherenkov tanks took data until December 2005 when deployment of the next set of strings and tanks began. We have analyzed these data, demonstrating that the performance of the system meets or exceeds design requirements. Times are determined across the whole array to a relative precision of better than 3 ns, allowing reconstruction of muon tracks and light bursts in the ice, of air-showers in the surface array and of events seen in coincidence…
Search for Neutrino-Induced Cascades with AMANDA
We report on a search for electro-magnetic and/or hadronic showers (cascades) induced by high energy neutrinos in the data collected with the AMANDA II detector during the year 2000. The observed event rates are consistent with the expectations for atmospheric neutrinos and muons. We place upper limits on a diffuse flux of extraterrestrial electron, tau and muon neutrinos. A flux of neutrinos with a spectrum $\Phi \propto E^{-2}$ which consists of an equal mix of all flavors, is limited to $E^2 \Phi(E)=8.6 x 10^{-7} GeV/(cm^{2} s sr)$ at a 90% confidence level for a neutrino energy range 50 TeV to 5 PeV. We present bounds for specific extraterrestrial neutrino flux predictions. Several of t…
Flux limits on ultra high energy neutrinos with AMANDA-B10
Abstract Data taken during 1997 with the AMANDA-B10 detector are searched for a diffuse flux of neutrinos of all flavors with energies above 10 16 eV. At these energies the Earth is opaque to neutrinos, and thus neutrino induced events are concentrated at the horizon. The background are large muon bundles from down-going atmospheric air shower events. No excess events above the background expectation are observed and a neutrino flux following E −2 , with an equal mix of all flavors, is limited to E 2 Φ (10 15 eV E 18 eV) ⩽ 0.99 × 10 −6 GeV cm −2 s −1 sr −1 at 90% confidence level. This is the most restrictive experimental bound placed by any neutrino detector at these energies. Bound…
NEUTRINO ASTRONOMY AND COSMIC RAYS AT THE SOUTH POLE: LATEST RESULTS FROM AMANDA AND PERSPECTIVES FOR ICECUBE
The AMANDA neutrino telescope has been in operation at the South Pole since 1996. The present final array configuration, operational since 2000, consists of 677 photomultiplier tubes arranged in 19 strings, buried at depths between 1500 and 2000 m in the ice. The most recent results on a multi-year search for point sources of neutrinos will be shown. The study of events triggered in coincidence with the surface array SPASE and AMANDA provided a result on cosmic ray composition. Expected improvements from IceCube/IceTop will also be discussed.
Resonant origin for density fluctuations deep within the Sun: helioseismology and magneto-gravity waves
We analyze helioseismic waves near the solar equator in the presence of magnetic fields deep within the solar radiative zone. We find that reasonable magnetic fields can significantly alter the shapes of the wave profiles for helioseismic g-modes. They can do so because the existence of density gradients allows g-modes to resonantly excite Alfven waves, causing mode energy to be funnelled along magnetic field lines, away from the solar equatorial plane. The resulting wave forms show comparatively sharp spikes in the density profile at radii where these resonances take place. We estimate how big these waves might be in the Sun, and perform a first search for observable consequences. We find …
Cornering solar radiative-zone fluctuations with KamLAND and SNO salt
We update the best constraints on fluctuations in the solar medium deep within the solar Radiative Zone to include the new SNO-salt solar neutrino measurements. We find that these new measurements are now sufficiently precise that neutrino oscillation parameters can be inferred independently of any assumptions about fluctuation properties. Constraints on fluctuations are also improved, with amplitudes of 5% now excluded at the 99% confidence level for correlation lengths in the range of several hundred km. Because they are sensitive to correlation lengths which are so short, these solar neutrino results are complementary to constraints coming from helioseismology.
IceCube contributions to the XIV International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2006)
IceCube contributions to the XIV International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2006) Weihai, China - August 15-22
Optical properties of deep glacial ice at the South Pole
We have remotely mapped optical scattering and absorption in glacial ice at the South Pole for wavelengths between 313 and 560 nm and depths between 1100 and 2350 m. We used pulsed and continuous light sources embedded with the AMANDA neutrino telescope, an array of more than six hundred photomultiplier tubes buried deep in the ice. At depths greater than 1300 m, both the scattering coefficient and absorptivity follow vertical variations in concentration of dust impurities, which are seen in ice cores from other Antarctic sites and which track climatological changes. The scattering coefficient varies by a factor of seven, and absorptivity (for wavelengths less than ∼450 nm) varies by a fact…
The IceCube prototype string in Amanda
The Antarctic Muon And Neutrino Detector Array (Amanda) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electrons. IceCube is a cubic-kilometer-sized expansion of Amanda currently being built at the South Pole. In IceCube the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new all-digital technology was deployed in the Amanda array in the year 2000. In this paper we describe the technology and demonst…
Limits on the muon flux from neutralino annihilations at the center of the Earth with AMANDA
A search has been performed for nearly vertically upgoing neutrino-induced muons with the Antarctic Muon And Neutrino Detector Array (AMANDA), using data taken over the three year period 1997–99. No excess above the expected atmospheric neutrino background has been found. Upper limits at 90% confidence level have been set on the annihilation rate of neutralinos at the center of the Earth, as well as on the muon flux at AMANDA induced by neutrinos created by the annihilation products.
Five years of searches for point sources of astrophysical neutrinos with the AMANDA-II neutrino telescope
We report the results of a five-year survey of the northern sky to search for point sources of high energy neutrinos. The search was performed on the data collected with the AMANDA-II neutrino telescope in the years 2000 to 2004, with a live-time of 1001 days. The sample of selected events consists of 4282 upward going muon tracks with high reconstruction quality and an energy larger than about 100 GeV. We found no indication of point sources of neutrinos and set 90% confidence level flux upper limits for an all-sky search and also for a catalog of 32 selected sources. For the all-sky search, our average (over declination and right ascension) experimentally observed upper limit \Phi^{0}=(E/…
Results from the AMANDA neutrino telescope
The Amanda neutrino telescope at the South Pole has been taking data since 1996. Stepwise upgraded, it reached its final stage in January 2000. We present results from the search for extraterrestrial neutrinos, neutrinos from dark matter annihilation and magnetic monopoles.
On the selection of AGN neutrino source candidates for a source stacking analysis with neutrino telescopes
The sensitivity of a search for sources of TeV neutrinos can be improved by grouping potential sources together into generic classes in a procedure that is known as source stacking. In this paper, we define catalogs of Active Galactic Nuclei (AGN) and use them to perform a source stacking analysis. The grouping of AGN into classes is done in two steps: first, AGN classes are defined, then, sources to be stacked are selected assuming that a potential neutrino flux is linearly correlated with the photon luminosity in a certain energy band (radio, IR, optical, keV, GeV, TeV). Lacking any secure detailed knowledge on neutrino production in AGN, this correlation is motivated by hadronic AGN mode…
Large mixing angle oscillations as a probe of the deep solar interior
We re-examine the sensitivity of solar neutrino oscillations to noise in the solar interior using the best current estimates of neutrino properties. Our results show that the measurement of neutrino properties at KamLAND provides new information about fluctuations in the solar environment on scales to which standard helioseismic constraints are largely insensitive. We also show how the determination of neutrino oscillation parameters from a combined fit of KamLAND and solar data depends strongly on the magnitude of solar density fluctuations. We argue that a resonance between helioseismic and Alfven waves might provide a physical mechanism for generating these fluctuations and, if so, neutr…
Limits to the muon flux from neutralino annihilations in the Sun with the AMANDA detector
A search for an excess of muon-neutrinos from neutralino annihilations in the Sun has been performed with the AMANDA-II neutrino detector using data collected in 143.7 days of live-time in 2001. No excess over the expected atmospheric neutrino background has been observed. An upper limit at 90% confidence level has been obtained on the annihilation rate of captured neutralinos in the Sun, as well as the corresponding muon flux limit at the Earth, both as functions of the neutralino mass in the range 100 GeV-5000 GeV.