Search results for "Icecube"
showing 10 items of 71 documents
A Search for a Diffuse Flux of Astrophysical Muon Neutrinos with the IceCube 40-String Detector
2011
The IceCube Neutrino Observatory is a 1 km$^{3}$ detector currently taking data at the South Pole. One of the main strategies used to look for astrophysical neutrinos with IceCube is the search for a diffuse flux of high-energy neutrinos from unresolved sources. A hard energy spectrum of neutrinos from isotropically distributed astrophysical sources could manifest itself as a detectable signal that may be differentiated from the atmospheric neutrino background by spectral measurement. This analysis uses data from the IceCube detector collected in its half completed configuration which operated between April 2008 and May 2009 to search for a diffuse flux of astrophysical muon neutrinos. A to…
Search for a diffuse flux of astrophysical muon neutrinos with the IceCube 59-string configuration
2013
A search for high-energy neutrinos was performed using data collected by the IceCube Neutrino Observatory from May 2009 to May 2010, when the array was running in its 59-string configuration. The data sample was optimized to contain muon neutrino induced events with a background contamination of atmospheric muons of less than 1%. These data, which are dominated by atmospheric neutrinos, are analyzed with a global likelihood fit to search for possible contributions of prompt atmospheric and astrophysical neutrinos, neither of which have yet been identified. Such signals are expected to follow a harder energy spectrum than conventional atmospheric neutrinos. In addition, the zenith angle dist…
First Observation of PeV-Energy Neutrinos with IceCube
2013
We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04 $\pm$ 0.16 and 1.14 $\pm$ 0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current $\nu_{e,\mu,\tau}$ ($\bar\nu_{e,\mu,\tau}$) or charged-current $\nu_{e}$ ($\bar\nu_{e}$) interactions within the IceCube detector. The events were discovered in a search for ultra-high energy neutrinos using data corresponding to 615.9 days effective livetime. The expected number of atmospheric background is $0.082 \pm 0.004 \text{(stat)}^{+0.041}_{-0.057} \text{(syst)}$. T…
Background studies for acoustic neutrino detection at the South Pole
2011
The detection of acoustic signals from ultra-high energy neutrino interactions is a promising method to measure the tiny flux of cosmogenic neutrinos expected on Earth. The energy threshold for this process depends strongly on the absolute noise level in the target material. The South Pole Acoustic Test Setup (SPATS), deployed in the upper part of four boreholes of the IceCube Neutrino Observatory, has monitored the noise in Antarctic ice at the geographic South Pole for more than two years down to 500 m depth. The noise is very stable and Gaussian distributed. Lacking an in-situ calibration up to now, laboratory measurements have been used to estimate the absolute noise level in the 10 to …
EV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory
2020
Physical review letters 125(14), 141801 (1-11) (2020). doi:10.1103/PhysRevLett.125.141801
The Pros and Cons of Beyond Standard Model Interpretations of ANITA Events
2019
The Antarctic Impulsive Transient Antenna (ANITA) experiment has observed two air shower events with energy $\sim 500~{\rm PeV}$ emerging from the Earth with exit angles $\sim 30^\circ$ above the horizon. As was immediately noted by the ANITA Collaboration, these events (in principle) could originate in the atmospheric decay of an upgoing $\tau$-lepton produced through a charged current interaction of a $\nu_\tau$ inside the Earth. However, the relatively steep arrival angles of these perplexing events create tension with the standard model (SM) neutrino-nucleon interaction cross section. Deepening the conundrum, the IceCube neutrino telescope and the Pierre Auger Observatory with substanti…
Search for cosmic sources in neutrino telescopes and time calibration in the ANTARES neutrino telescope
2018
Aunque la astronomía de neutrinos es una disciplina muy reciente, está resultando ser muy en un estado estimulante. Los diversos resultados publicados por la colaboración IceCube han mostrado la existencia de un flujo de neutrinos cósmicos de altas energías, del cual se desconoce su origen, y del que no se ha observado una dirección privilegiada. El telescopio de neutrinos ANTARES ha sido capaz de excluir la posibilidad de que algunos de los eventos observados por IceCube se hayan producido por una fuente puntual en la región del centro galáctico. Además, el último análisis de flujos difusos de ANTARES muestra un resultado compatible con el flujo observado por IceCube. Actualmente, existen …
Time-integrated Neutrino Source Searches with 10 years of IceCube Data
2020
Physical review letters 124(5), 051103 (1-9) (2020). doi:10.1103/PhysRevLett.124.051103
Neutrinos below 100 TeV from the southern sky employing refined veto techniques to IceCube data
2020
Many Galactic sources of gamma rays, such as supernova remnants, are expected to produce neutrinos with a typical energy cutoff well below 100 TeV. For the IceCube Neutrino Observatory located at the South Pole, the southern sky, containing the inner part of the Galactic plane and the Galactic Center, is a particularly challenging region at these energies, because of the large background of atmospheric muons. In this paper, we present recent advancements in data selection strategies for track-like muon neutrino events with energies below 100 TeV from the southern sky. The strategies utilize the outer detector regions as veto and features of the signal pattern to reduce the background of atm…
Computational Techniques for the Analysis of Small Signals in High-Statistics Neutrino Oscillation Experiments
2020
The current and upcoming generation of Very Large Volume Neutrino Telescopes – collecting unprecedented quantities of neutrino events – can be used to explore subtle effects in oscillation physics, such as (but not restricted to) the neutrino mass ordering. The sensitivity of an experiment to these effects can be estimated from Monte Carlo simulations. With the high number of events that will be collected, there is a trade-off between the computational expense of running such simulations and the inherent statistical uncertainty in the determined values. In such a scenario, it becomes impractical to produce and use adequately-sized sets of simulated events with traditional methods, such as M…