| 1. |
- Aad, G, et al.
(författare)
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- 2015
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swepub:Mat__t
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| 2. |
- Aad, G., et al.
(författare)
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- 2011
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Abbasi, R., et al.
(författare)
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Measurement of atmospheric neutrino mixing with improved IceCube DeepCore calibration and data processing
- 2023
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 108:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe a new data sample of IceCube DeepCore and report on the latest measurement of atmospheric neutrino oscillations obtained with data recorded between 2011-2019. The sample includes significant improvements in data calibration, detector simulation, and data processing, and the analysis benefits from a sophisticated treatment of systematic uncertainties, with significantly greater level of detail since our last study. By measuring the relative fluxes of neutrino flavors as a function of their reconstructed energies and arrival directions we constrain the atmospheric neutrino mixing parameters to be sin2θ23=0.51±0.05 and Δm322=2.41±0.07×10-3 eV2, assuming a normal mass ordering. The errors include both statistical and systematic uncertainties. The resulting 40% reduction in the error of both parameters with respect to our previous result makes this the most precise measurement of oscillation parameters using atmospheric neutrinos. Our results are also compatible and complementary to those obtained using neutrino beams from accelerators, which are obtained at lower neutrino energies and are subject to different sources of uncertainties.
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| 4. |
- Abbasi, R., et al.
(författare)
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Observation of seasonal variations of the flux of high-energy atmospheric neutrinos with IceCube
- 2023
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Ingår i: European Physical Journal C. - : Springer. - 1434-6044 .- 1434-6052. ; 83:9
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Tidskriftsartikel (refereegranskat)abstract
- Atmospheric muon neutrinos are produced by meson decays in cosmic-ray-induced air showers. The flux depends on meteorological quantities such as the air temperature, which affects the density of air. Competition between decay and re-interaction of those mesons in the first particle production generations gives rise to a higher neutrino flux when the air density in the stratosphere is lower, corresponding to a higher temperature. A measurement of a temperature dependence of the atmospheric νμ flux provides a novel method for constraining hadronic interaction models of air showers. It is particularly sensitive to the production of kaons. Studying this temperature dependence for the first time requires a large sample of high-energy neutrinos as well as a detailed understanding of atmospheric properties. We report the significant (>10σ) observation of a correlation between the rate of more than 260,000 neutrinos, detected by IceCube between 2012 and 2018, and atmospheric temperatures of the stratosphere, measured by the Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s AQUA satellite. For the observed 10 % seasonal change of effective atmospheric temperature we measure a 3.5(3) % change in the muon neutrino flux. This observed correlation deviates by about 2-3 standard deviations from the expected correlation of 4.3 % as obtained from theoretical predictions under the assumption of various hadronic interaction models.
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| 5. |
- Abbasi, R., et al.
(författare)
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Search for Galactic Core-collapse Supernovae in a Decade of Data Taken with the IceCube Neutrino Observatory
- 2024
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Ingår i: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 1538-4357 .- 0004-637X. ; 961:1
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Tidskriftsartikel (refereegranskat)abstract
- The IceCube Neutrino Observatory has been continuously taking data to search for O(0.5–10) s long neutrino bursts since 2007. Even if a Galactic core-collapse supernova is optically obscured or collapses to a black hole instead of exploding, it will be detectable via the O(10) MeV neutrino burst emitted during the collapse. We discuss a search for such events covering the time between 2008 April 17 and 2019 December 31. Considering the average data taking and analysis uptime of 91.7% after all selection cuts, this is equivalent to 10.735 yr of continuous data taking. In order to test the most conservative neutrino production scenario, the selection cuts were optimized for a model based on an 8.8 solar mass progenitor collapsing to an O–Ne–Mg core. Conservative assumptions on the effects of neutrino oscillations in the exploding star were made. The final selection cut was set to ensure that the probability to detect such a supernova within the Milky Way exceeds 99%. No such neutrino burst was found in the data after performing a blind analysis. Hence, a 90% C.L. upper limit on the rate of core-collapse supernovae out to distances of ≈25 kpc was determined to be 0.23 yr−1. For the more distant Magellanic Clouds, only high neutrino luminosity supernovae will be detectable by IceCube, unless external information on the burst time is available. We determined a model-independent limit by parameterizing the dependence on the neutrino luminosity and the energy spectrum.
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| 6. |
- Abbasi, R., et al.
(författare)
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Search for neutrino lines from dark matter annihilation and decay with IceCube
- 2023
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 108:10
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Tidskriftsartikel (refereegranskat)abstract
- Dark matter particles in the Galactic Center and halo can annihilate or decay into a pair of neutrinos producing a monochromatic flux of neutrinos. The spectral feature of this signal is unique and it is not expected from any astrophysical production mechanism. Its observation would constitute a dark matter smoking gun signal. We performed the first dedicated search with a neutrino telescope for such signal, by looking at both the angular and energy information of the neutrino events. To this end, a total of five years of IceCube's DeepCore data has been used to test dark matter masses ranging from 10 GeV to 40 TeV. No significant neutrino excess was found and upper limits on the annihilation cross section, as well as lower limits on the dark matter lifetime, were set. The limits reached are of the order of 10-24 cm3/s for an annihilation and up to 1027 s for decaying dark matter. Using the same data sample we also derive limits for dark matter annihilation or decay into a pair of Standard Model charged particles.
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| 7. |
- Abbasi, R., et al.
(författare)
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Citizen science for IceCube: Name that Neutrino
- 2024
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Ingår i: European Physical Journal Plus. - 2190-5444. ; 139:6
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Tidskriftsartikel (refereegranskat)abstract
- Name that Neutrino is a citizen science project where volunteers aid in classification of events for the IceCube Neutrino Observatory, an immense particle detector at the geographic South Pole. From March 2023 to September 2023, volunteers did classifications of videos produced from simulated data of both neutrino signal and background interactions. Name that Neutrino obtained more than 128,000 classifications by over 1800 registered volunteers that were compared to results obtained by a deep neural network machine-learning algorithm. Possible improvements for both Name that Neutrino and the deep neural network are discussed.
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| 8. |
- Abbasi, R., et al.
(författare)
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IceCat-1: The IceCube Event Catalog of Alert Tracks
- 2023
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Ingår i: Astrophysical Journal, Supplement Series. - : IOP Publishing Ltd. - 1538-4365 .- 0067-0049. ; 269:1
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Tidskriftsartikel (refereegranskat)abstract
- We present a catalog of likely astrophysical neutrino track-like events from the IceCube Neutrino Observatory. IceCube began reporting likely astrophysical neutrinos in 2016, and this system was updated in 2019. The catalog presented here includes events that were reported in real time since 2019, as well as events identified in archival data samples starting from 2011. We report 275 neutrino events from two selection channels as the first entries in the catalog, the IceCube Event Catalog of Alert Tracks, which will see ongoing extensions with additional alerts. The Gold and Bronze alert channels respectively provide neutrino candidates with a 50% and 30% probability of being astrophysical, on average assuming an astrophysical neutrino power-law energy spectral index of 2.19. For each neutrino alert, we provide the reconstructed energy, direction, false-alarm rate, probability of being astrophysical in origin, and likelihood contours describing the spatial uncertainty in the alert's reconstructed location. We also investigate a directional correlation of these neutrino events with gamma-ray and X-ray catalogs, including 4FGL, 3HWC, TeVCat, and Swift-BAT.
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| 9. |
- Abbasi, R., et al.
(författare)
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Search for 10-1000 GeV Neutrinos from Gamma-Ray Bursts with IceCube
- 2024
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Ingår i: Astrophysical Journal. - : Institute of Physics (IOP). - 1538-4357 .- 0004-637X. ; 964:2
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Tidskriftsartikel (refereegranskat)abstract
- We present the results of a search for 10-1000 GeV neutrinos from 2268 gamma-ray bursts (GRBs) over 8 yr of IceCube-DeepCore data. This work probes burst physics below the photosphere where electromagnetic radiation cannot escape. Neutrinos of tens of giga electronvolts are predicted in sub-photospheric collision of free-streaming neutrons with bulk-jet protons. In a first analysis, we searched for the most significant neutrino-GRB coincidence using six overlapping time windows centered on the prompt phase of each GRB. In a second analysis, we conducted a search for a group of GRBs, each individually too weak to be detectable, but potentially significant when combined. No evidence of neutrino emission is found for either analysis. The most significant neutrino coincidence is for Fermi-GBM GRB bn 140807500, with a p-value of 0.097 corrected for all trials. The binomial test used to search for a group of GRBs had a p-value of 0.65 after all trial corrections. The binomial test found a group consisting only of GRB bn 140807500 and no additional GRBs. The neutrino limits of this work complement those obtained by IceCube at tera electronvolt to peta electronvolt energies. We compare our findings for the large set of GRBs as well as GRB 221009A to the sub-photospheric neutron-proton collision model and find that GRB 221009A provides the most constraining limit on baryon loading. For a jet Lorentz factor of 300 (800), the baryon loading on GRB 221009A is lower than 3.85 (2.13) at a 90% confidence level.
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| 10. |
- Abbasi, R., et al.
(författare)
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Cosmic ray composition and energy spectrum from 1-30 PeV using the 40-string configuration of IceTop and IceCube
- 2013
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Ingår i: Astroparticle physics. - : Elsevier BV. - 0927-6505 .- 1873-2852. ; 42, s. 15-32
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Tidskriftsartikel (refereegranskat)abstract
- The mass composition of high energy cosmic rays depends on their production, acceleration, and propagation. The study of cosmic ray composition can therefore reveal hints of the origin of these particles. At the South Pole, the IceCube Neutrino Observatory is capable of measuring two components of cosmic ray air showers in coincidence: the electromagnetic component at high altitude (2835 m) using the IceTop surface array, and the muonic component above ∼1 TeV using the IceCube array. This unique detector arrangement provides an opportunity for precision measurements of the cosmic ray energy spectrum and composition in the region of the knee and beyond. We present the results of a neural network analysis technique to study the cosmic ray composition and the energy spectrum from 1 PeV to 30 PeV using data recorded using the 40-string/40-station configuration of the IceCube Neutrino Observatory.
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| 11. |
- Abbasi, R., et al.
(författare)
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An improved method for measuring muon energy using the truncated mean of dE/dx
- 2013
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 703, s. 190-198
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Tidskriftsartikel (refereegranskat)abstract
- The measurement of muon energy is critical for many analyses in large Cherenkov detectors, particularly those that involve separating extraterrestrial neutrinos from the atmospheric neutrino background. Muon energy has traditionally been determined by measuring the specific energy loss (dE/dx) along the muon's path and relating the dE/dx to the muon energy. Because high-energy muons (Eμ>1TeV) lose energy randomly, the spread in dE/dx values is quite large, leading to a typical energy resolution of 0.29 in log10(Eμ) for a muon observed over a 1 km path length in the IceCube detector. In this paper, we present an improved method that uses a truncated mean and other techniques to determine the muon energy. The muon track is divided into separate segments with individual dE/dx values. The elimination of segments with the highest dE/dx results in an overall dE/dx that is more closely correlated to the muon energy. This method results in an energy resolution of 0.22 in log10(Eμ), which gives a 26% improvement. This technique is applicable to any large water or ice detector and potentially to large scintillator or liquid argon detectors.
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| 12. |
- Abbasi, R., et al.
(författare)
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Searches for high-energy neutrino emission in the galaxy with the combined icecube-amanda detector
- 2013
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 763:1, s. 33-
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Tidskriftsartikel (refereegranskat)abstract
- We report on searches for neutrino sources at energies above 200 GeV in the Northern sky of the Galactic plane, using the data collected by the South Pole neutrino telescope, IceCube, and AMANDA. The Galactic region considered in this work includes the local arm toward the Cygnus region and our closest approach to the Perseus Arm. The searches are based on the data collected between 2007 and 2009. During this time AMANDA was an integrated part of IceCube, which was still under construction and operated with 22 strings (2007-2008) and 40 strings (2008-2009) of optical modules deployed in the ice. By combining the advantages of the larger IceCube detector with the lower energy threshold of the more compact AMANDA detector, we obtain an improved sensitivity at energies below ∼10 TeV with respect to previous searches. The analyses presented here are a scan for point sources within the Galactic plane, a search optimized for multiple and extended sources in the Cygnus region, which might be below the sensitivity of the point source scan, and studies of seven pre-selected neutrino source candidates. For one of them, Cygnus X-3, a time-dependent search for neutrino emission in coincidence with observed radio and X-ray flares has been performed. No evidence of a signal is found, and upper limits are reported for each of the searches. We investigate neutrino spectra proportional to E -2 and E -3 in order to cover the entire range of possible neutrino spectra. The steeply falling E -3 neutrino spectrum can also be used to approximate neutrino energy spectra with energy cutoffs below 50 TeV since these result in a similar energy distribution of events in the detector. For the region of the Galactic plane visible in the Northern sky, the 90% confidence level muon neutrino flux upper limits are in the range E 3 dN/dE ∼ 5.4-19.5 × 10-11 TeV2 cm-2 s-1 for point-like neutrino sources in the energy region [180.0 GeV-20.5 TeV]. These represent the most stringent upper limits for soft-spectra neutrino sources within the Galaxy reported to date.
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| 13. |
- Abbasi, R., et al.
(författare)
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A Search for Coincident Neutrino Emission from Fast Radio Bursts with Seven Years of IceCube Cascade Events
- 2023
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Ingår i: Astrophysical Journal. - : Institute of Physics (IOP). - 1538-4357 .- 0004-637X. ; 946:2
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the results of a search for neutrinos that are spatially and temporally coincident with 22 unique, nonrepeating fast radio bursts (FRBs) and one repeating FRB (FRB 121102). FRBs are a rapidly growing class of Galactic and extragalactic astrophysical objects that are considered a potential source of high-energy neutrinos. The IceCube Neutrino Observatory's previous FRB analyses have solely used track events. This search utilizes seven years of IceCube cascade events which are statistically independent of track events. This event selection allows probing of a longer range of extended timescales due to the low background rate. No statistically significant clustering of neutrinos was observed. Upper limits are set on the time-integrated neutrino flux emitted by FRBs for a range of extended time windows.
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| 14. |
- Ahrens, J., et al.
(författare)
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Calibration and survey of AMANDA with the SPASE detectors
- 2004
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 522:3, s. 347-359
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Tidskriftsartikel (refereegranskat)abstract
- We report on the analysis of air showers observed in coincidence by the Antarctic Muon and Neutrino detector array (AMANDA-B10) and the South Pole Air Shower Experiment (SPASE-1 and SPASE-2). We discuss the use of coincident events for calibration and survey of the deep AMANDA detector as well as the response of AMANDA to muon bundles. This analysis uses data taken during 1997 when both SPASE-1 and SPASE-2 were in operation to provide a stereo view of AMANDA. © 2003 Elsevier B.V. All rights reserved.
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| 15. |
- Ahrens, J., et al.
(författare)
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Measurement of the cosmic ray composition at the knee with the SPASE-2/AMANDA-B10 detectors
- 2004
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Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 21:6, s. 565-581
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Tidskriftsartikel (refereegranskat)abstract
- The mass composition of high-energy cosmic rays at energies above 1015 eV can provide crucial information for the understanding of their origin. Air showers were measured simultaneously with the SPASE-2 air shower array and the AMANDA-B10 Cherenkov telescope at the South Pole. This combination has the advantage to sample almost all high-energy shower muons and is thus a new approach to the determination of the cosmic ray composition. The change in the cosmic ray mass composition was measured versus existing data from direct measurements at low energies. Our data show an increase of the mean log atomic mass 〈lnA〉 by about 0.8 between 500 TeV and 5 PeV. This trend of an increasing mass through the "knee" region is robust against a variety of systematic effects. © 2004 Elsevier B.V. All rights reserved.
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| 16. |
- Ahrens, J., et al.
(författare)
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Muon track reconstruction and data selection techniques in AMANDA
- 2004
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 524:1-3, s. 169-194
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Tidskriftsartikel (refereegranskat)abstract
- The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500 and 2000 m. The primary goal of this detector is to discover astrophysical sources of high-energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of reconstruction, which have been successfully implemented within AMANDA. Strategies for optimizing the reconstruction performance and rejecting background are presented. For a typical analysis procedure the direction of tracks are reconstructed with about 2° accuracy. © 2004 Elsevier B.V. All rights reserved.
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| 17. |
- Ahrens, J., et al.
(författare)
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Physics and operation of the AMANDA-II high energy neutrino telescope
- 2002
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Ingår i: Proceedings of the SPIE - The International Society for Optical Engineering 2003. - : Institution of Electrical Engineers (IEE). ; , s. 79-91
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Konferensbidrag (refereegranskat)abstract
- This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-B10, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we focus on the search for continuous emission from astrophysical point sources and the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
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| 18. |
- Ahrens, J., et al.
(författare)
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Results from the AMANDA telescope
- 2003
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Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 721, s. C545-C548
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Tidskriftsartikel (refereegranskat)abstract
- We present results from the AMANDA high energy neutrino telescope located at the South Pole. They include measurements of the atmospheric neutrino flux, search for UHE point sources, and diffuse sources producing electromagnetic/hadronic showers at the detector or close to it.
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| 19. |
- Ahrens, J., et al.
(författare)
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Search for Extraterrestrial Point Sources of Neutrinos with AMANDA-II
- 2004
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 92:7, s. 711021-711025
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Tidskriftsartikel (refereegranskat)abstract
- The results of a search for point sources of high energy neutrinos in the northern hemisphere were presented using AMANDA-II data collected in the year 2000. The results included the flux limits on several active-galactic-nuclei blazars, microquasars, magnetars, and other candidate neutrino sources. A search for excesses above a random background of cosmic ray induced atmospheric neutrinos and misreconstructed downgoing cosmic-rays muons, which revealed no statistically significant neutrino point sources was also presented. It was shown that AMANDA-II had achieved the sensitivity required to probe known TeV γ-ray sources such as the blazar Markarian 501 in its 1997 flaring state at a level where neutrino and γ-ray fluxes were equal.
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| 20. |
- Kowalski, Marek, et al.
(författare)
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Physics results from the AMANDA neutrino detector
- 2001
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Ingår i: Proceedings of Science. - 1824-8039. ; HEP2001
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Tidskriftsartikel (refereegranskat)abstract
- In the winter season of 2000, the AMANDA (Antarctic Muon And NeutrinoDetector Array) detector was completed to its nal state. We report on major physicsresults obtained from the AMANDA-B10 detector, as well as initial results of the fullAMANDA-II detector.
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| 21. |
- Ahrens, J., et al.
(författare)
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Results from the Antarctic muon and nuetrino detector array
- 2003
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Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 118, s. 371-379
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Tidskriftsartikel (refereegranskat)abstract
- We show new results from both the older and newer incarnations of AMANDA (AMANDA-B10 and AMANDA-II, respectively). These results demonstrate that AMANDA is a functioning, multipurpose detector with significant physics and astrophysics reach. They include a new higher-statistics measurement of the atmospheric muon neutrino flux and preliminary results from searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, gamma-ray bursters and diffuse sources producing muons in the detector, and diffuse sources producing electromagnetic or hadronic showers in or near the detector.
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| 22. |
- Ahrens, J., et al.
(författare)
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Search for neutrino-induced cascades with the AMANDA detector
- 2003
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Ingår i: Physical Review D. - : American Physical Society (APS). - 1550-7998 .- 1550-2368. ; 67:1, s. 012003-
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Tidskriftsartikel (refereegranskat)abstract
- We report on a search for electromagnetic and/or hadronic showers (cascades) induced by a diffuse flux of neutrinos with energies between 5 TeV and 300 TeV from extraterrestrial sources. Cascades may be produced by matter interactions of all flavors of neutrinos, and contained cascades have better energy resolution and afford better background rejection than throughgoing νμ-induced muons. Data taken in 1997 with the AMANDA detector were searched for events with a high-energy cascadelike signature. The observed events are consistent with expected backgrounds from atmospheric neutrinos and catastrophic energy losses from atmospheric muons. Effective volumes for all flavors of neutrinos, which allow the calculation of limits for any neutrino flux model, are presented. The limit on cascades from a diffuse flux of νe+ νμ + ντ+ ν̄e + ν̄μ+ ν̄τ is E2(dΦ/dE)<9.8×10-6 GeV cm-2 s-1 sr-1, assuming a neutrino flavor flux ratio of 1:1:1 at the detector. The limit on cascades from a diffuse flux of νe+ν̄e is E2(dΦ/dE)<6. 5×10-6 GeV cm-2 s-1 sr-1, independent of the assumed neutrino flavor flux ratio. © 2003 The American Physical Society.
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| 23. |
- Böser, S, et al.
(författare)
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SPATS : An acoustic array at the South Pole
- 2007
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Ingår i: Journal of Physics, Conference Series. - : Institute of Physics. - 1742-6588 .- 1742-6596. ; 60, s. 292-295
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The detection of extraterrestrial EHE neutrinos requires detection volumes at least one order of magnitude larger than currently constructed km3 optical neutrino detectors. In ice, it is anticipated that the absorption length for acoustic waves reaches up to to several kilometers. This makes ice an attractive host environment for a next generation acoustic neutrino detector. To measure the acoustic properties of ice at South Pole, a test setup has been developed, ready to be deployed in the 2006/07 summer season.
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| 24. |
- Böser, S, et al.
(författare)
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Status of the South Pole Acoustic Test Setup
- 2007
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Ingår i: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 81:1, s. 012010-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Due to the low flux of ultra-high energetic neutrinos induced in interactions of cosmic rays with the cosmic microwave background, very large instrumented volumes and new registration techniques are necessary for their detection. The south polar ice offers the unique opportunity to implement existing Cherenkov techniques as well as registration of radio and acoustic waves from the neutrino interaction. A simulation of a ~ 120 km3 hybrid optical/radio/acoustic detector showed that event rates of ~ 10 per year can be achieved. In this simulation the ultrasonic parameters of antarctic ice regarding absorption, scattering and environmental noise pose the key uncertainty. To evaluate the acoustic properties in-situ, the South Pole Acoustic Test Setup (SPATS) has been created. An array of custom-made ultrasonic sensors and transmitters will be deployed on three strings in the upper 400 m of the holes of the IceCube experiment. The status of the experiment and a first evaluation of its performance are presented here.
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| 25. |
- Böser, S, et al.
(författare)
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The South Pole Acoustic Test Setup : calibrations and lake test
- 2007
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Ingår i: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 81, s. 012016-
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Tidskriftsartikel (refereegranskat)abstract
- Abstract. In order to detect the small neutrino fluxes expected at ultra-high energies, large volumes of materials have to be instrumented with inexpensive but sensitive acoustic sensors. The South Pole Acoustic Test Setup (SPATS) will be installed in the Antarctic ice during the polar season 2006/2007 after which the collected data will be used to reveal the acoustic properties of the South Polar ice cap. The developed piezoceramic based ultrasound sensors and transmitters that are part of this system have been extensively studied during calibration measurements in water, using a commercial hydrophone as reference. Also, a SPATS system test was accomplished in Lake Torneträsk, Abisko (Sweden). This allowed verification of the DAQ system, transmitter range and sensor performance. Here the results of the calibrations and the Abisko lake measurements are reported.
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