SEARCHES FOR EXTENDED AND POINT-LIKE NEUTRINO SOURCES WITH FOUR YEARS OF ICECUBE DATA

Aartsen, M. G.,Ackermann, M.,Adams, J.,Aguilar, J. A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Anderson, T.,Arguelles, C.,Arlen, T. C.,Auffenberg, J.,Bai, X.,Barwick, S. W.,Baum, V.,Beatty, J. J.,Tjus, J. Be IOP Publishing 2014 The Astrophysical journal Vol.796 No.2

<P>We present results on searches for point-like sources of neutrinos using four years of IceCube data, including the first year of data from the completed 86 string detector. The total livetime of the combined data set is 1373 days. For an E-2 spectrum, the observed 90% C. L. flux upper limits are similar to 10(-12) TeV-1 cm(-2) s(-1) for energies between 1 TeV and 1 PeV in the northern sky and similar to 10(-11) TeV-1 cm(-2) s(-1) for energies between 100 TeV and 100 PeV in the southern sky. This represents a 40% improvement compared to previous publications, resulting from both the additional year of data and the introduction of improved reconstructions. In addition, we present the first results from an all-sky search for extended sources of neutrinos. We update the results of searches for neutrino emission from stacked catalogs of sources and test five new catalogs; two of Galactic supernova remnants and three of active galactic nuclei. In all cases, the data are compatible with the background-only hypothesis, and upper limits on the flux of muon neutrinos are reported for the sources considered.</P>

Apparent metabolizable energy, growth performance and carcass traits of Japanese quail fed select modern grain sorghum varieties

Moritz A. H.,Krombeen S. K.,Presgraves J.,Blair M. E.,Buresh R. E.,Bridges W. C.,Arguelles-Ramos M.,Wilmoth T. A. 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.12

Objective: This study was performed to determine the apparent metabolizable energy (AMEn) content of tannin-free red/bronze, white/tan and U.S. No. 2 varieties of grain sorghum for feeding Japanese quail and validate their nutrient profile by evaluating effects on performance and carcass traits with full-substitution of corn. Methods: Experiment 1 determined the AMEn content of red/bronze, white/tan, and U.S. No. 2 grain sorghum varieties fed to mixed-sex Japanese quail (Coturnix japonica) (n = 314) at 3 and 6-weeks of age. Analyses were based on a 2×4 factorial treatment design with age and grain types defining the treatments, and a randomized complete block experiment design with cage and trials defining the block. AMEn values were validated by evaluating the performance and carcass traits of Japanese quail (n = 644) from 1 to 40 days of age in Experiment 2 with birds were fed 1 of 4 complete diets. Statistical analyses were conducted on performance data and select individual carcass trait measurements. Results: Determined AMEn values at 3-weeks of age were 3,524±122.03 (red/bronze), 3,252± 122.03 (white/tan), and 3,039±123.44 (U.S. No. 2) kcal/kg. At 6-weeks of age, determined AMEn were 3,373±297.35 (red/bronze), 3,279±297.35 (white/tan), and 2,966±298.64 (U.S. No. 2) kcal/kg. Carcass traits showed live body weight (p = 0.0409) and hot carcass weight (p = 0.0234) were greatest in U.S. No. 2; however, carcass yield (p<0.0001) was lowest. No significant differences were observed among treatments for feed intake, feed conversion ratio, breast weight and breast yield (p>0.05). Conclusion: These studies demonstrated that tannin-free grain sorghum varieties may be a potential alternative to corn in quail diets while maintaining growth performance and carcass parameters. Objective: This study was performed to determine the apparent metabolizable energy (AME_n) content of tannin-free red/bronze, white/tan and U.S. No. 2 varieties of grain sorghum for feeding Japanese quail and validate their nutrient profile by evaluating effects on performance and carcass traits with full-substitution of corn.Methods: Experiment 1 determined the AME_n content of red/bronze, white/tan, and U.S. No. 2 grain sorghum varieties fed to mixed-sex Japanese quail (<i>Coturnix japonica</i>) (n = 314) at 3 and 6-weeks of age. Analyses were based on a 2×4 factorial treatment design with age and grain types defining the treatments, and a randomized complete block experiment design with cage and trials defining the block. AME_n values were validated by evaluating the performance and carcass traits of Japanese quail (n = 644) from 1 to 40 days of age in Experiment 2 with birds were fed 1 of 4 complete diets. Statistical analyses were conducted on performance data and select individual carcass trait measurements.Results: Determined AME_n values at 3-weeks of age were 3,524±122.03 (red/bronze), 3,252±122.03 (white/tan), and 3,039±123.44 (U.S. No. 2) kcal/kg. At 6-weeks of age, determined AME_n were 3,373±297.35 (red/bronze), 3,279±297.35 (white/tan), and 2,966±298.64 (U.S. No. 2) kcal/kg. Carcass traits showed live body weight (p = 0.0409) and hot carcass weight (p = 0.0234) were greatest in U.S. No. 2; however, carcass yield (p<0.0001) was lowest. No significant differences were observed among treatments for feed intake, feed conversion ratio, breast weight and breast yield (p>0.05).Conclusion: These studies demonstrated that tannin-free grain sorghum varieties may be a potential alternative to corn in quail diets while maintaining growth performance and carcass parameters.

PINGU: a vision for neutrino and particle physics at the South Pole

Aartsen, M G,Abraham, K,Ackermann, M,Adams, J,Aguilar, J A,Ahlers, M,Ahrens, M,Altmann, D,Andeen, K,Anderson, T,Ansseau, I,Anton, G,Archinger, M,Arguelles, C,Arlen, T C,Auffenberg, J,Axani, S,Bai, X,B Institute of Physics Publishing 2017 Journal of Physics. G, Nuclear and Particle Physic Vol.44 No.5

<P>The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill extension to the IceCube Neutrino Observatory. With detection technology modeled closely on the successful IceCube example, PINGU will provide a 6?Mton effective mass for neutrino detection with an energy threshold of a few GeV. With an unprecedented sample of over 60 000 atmospheric neutrinos per year in this energy range, PINGU will make highly competitive measurements of neutrino oscillation parameters in an energy range over an order of magnitude higher than long-baseline neutrino beam experiments. PINGU will measure the mixing parameters <img ALIGN='MIDDLE' ALT='${\theta }_{23}$' SRC='http://ej.iop.org/images/0954-3899/44/5/054006/jpgaa4973ieqn1.gif'/> and <img ALIGN='MIDDLE' ALT='${\rm{\Delta }}{m}_{32}^{2}$' SRC='http://ej.iop.org/images/0954-3899/44/5/054006/jpgaa4973ieqn2.gif'/>, including the octant of <img ALIGN='MIDDLE' ALT='${\theta }_{23}$' SRC='http://ej.iop.org/images/0954-3899/44/5/054006/jpgaa4973ieqn3.gif'/> for a wide range of values, and determine the neutrino mass ordering at <img ALIGN='MIDDLE' ALT='$3\sigma $' SRC='http://ej.iop.org/images/0954-3899/44/5/054006/jpgaa4973ieqn4.gif'/> median significance within five years of operation. PINGU’s high precision measurement of the rate of <img ALIGN='MIDDLE' ALT='${\nu }_{\tau }$' SRC='http://ej.iop.org/images/0954-3899/44/5/054006/jpgaa4973ieqn5.gif'/> appearance will provide essential tests of the unitarity of the 3?×?3 PMNS neutrino mixing matrix. PINGU will also improve the sensitivity of searches for low mass dark matter in the Sun, use neutrino tomography to directly probe the composition of the Earth’s core, and improve IceCube’s sensitivity to neutrinos from Galactic supernovae. Reoptimization of the PINGU design has permitted substantial reduction in both cost and logistical requirements while delivering performance nearly identical to configurations previously studied.</P>

All-flavour search for neutrinos from dark matter annihilations in the Milky Way with IceCube/DeepCore

Aartsen, M. G.,Abraham, K.,Ackermann, M.,Adams, J.,Aguilar, J. A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Andeen, K.,Anderson, T.,Ansseau, I.,Anton, G.,Archinger, M.,Arguelles, C.,Arlen, T. C.,Auffenberg, J Springer-Verlag 2016 European Physical Journal C Vol.76 No.10

<P>We present the first IceCube search for a signal of dark matter annihilations in the Milky Way using all-flavour neutrino-induced particle cascades. The analysis focuses on the DeepCore sub-detector of IceCube, and uses the surrounding IceCube strings as a veto region in order to select starting events in the DeepCore volume. We use 329 live-days of data from IceCube operating in its 86-string configuration during 2011-2012. No neutrino excess is found, the final result being compatible with the background-only hypothesis. From this null result, we derive upper limits on the velocity-averaged self-annihilation cross-section, , for dark matter candidate masses ranging from 30 GeV up to 10 TeV, assuming both a cuspy and a flat-cored dark matter halo profile. For dark matter masses between 200 GeV and 10 TeV, the results improve on all previous IceCube results on , reaching a level of 10 cm s, depending on the annihilation channel assumed, for a cusped NFW profile. The analysis demonstrates that all-flavour searches are competitive with muon channel searches despite the intrinsically worse angular resolution of cascades compared to muon tracks in IceCube.</P>

The IceProd framework: Distributed data processing for the IceCube neutrino observatory

Aartsen, M.G.,Abbasi, R.,Ackermann, M.,Adams, J.,Aguilar, J.A.,Ahlers, M.,Altmann, D.,Arguelles, C.,Auffenberg, J.,Bai, X.,Baker, M.,Barwick, S.W.,Baum, V.,Bay, R.,Beatty, J.J.,Becker Tjus, J.,Becker, Elsevier 2015 Journal of parallel and distributed computing Vol.75 No.-

<P><B>Abstract</B></P> <P>IceCube is a one-gigaton instrument located at the geographic South Pole, designed to detect cosmic neutrinos, identify the particle nature of dark matter, and study high-energy neutrinos themselves. Simulation of the IceCube detector and processing of data require a significant amount of computational resources. This paper presents the first detailed description of IceProd, a lightweight distributed management system designed to meet these requirements. It is driven by a central database in order to manage mass production of simulations and analysis of data produced by the IceCube detector. IceProd runs as a separate layer on top of other middleware and can take advantage of a variety of computing resources, including grids and batch systems such as CREAM, HTCondor, and PBS. This is accomplished by a set of dedicated daemons that process job submission in a coordinated fashion through the use of middleware plugins that serve to abstract the details of job submission and job management from the framework.</P> <P><B>Highlights</B></P> <P> <UL> <LI> IceProd is a lightweight distributed workflow management framework. </LI> <LI> Uses existing middleware and protocols. </LI> <LI> Runs at user-level and is easily adaptable to other applications. </LI> <LI> It has been successful in managing 450k cores across 25 computing centers. </LI> <LI> Identified areas of improvement including scalability and load balancing. </LI> </UL> </P>

THE DETECTION OF A SN IIn IN OPTICAL FOLLOW-UP OBSERVATIONS OF ICECUBE NEUTRINO EVENTS

Aartsen, M. G.,Abraham, K.,Ackermann, M.,Adams, J.,Aguilar, J. A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Anderson, T.,Archinger, M.,Arguelles, C.,Arlen, T. C.,Auffenberg, J.,Bai, X.,Barwick, S. W.,Baum, V. IOP Publishing 2015 The Astrophysical journal Vol.811 No.1

<P>The IceCube neutrino observatory pursues a follow-up program selecting interesting neutrino events in real-time and issuing alerts for electromagnetic follow-up observations. In 2012 March, the most significant neutrino alert during the first three years of operation was issued by IceCube. In the follow-up observations performed by the Palomar Transient Factory (PTF), a Type IIn supernova (SN IIn) PTF12csy was found 0.degrees 2 away from the neutrino alert direction, with an error radius of 0.degrees 54. It has a redshift of z = 0.0684, corresponding to a luminosity distance of about 300 Mpc and the Pan-STARRS1 survey shows that its explosion time was at least 158 days (in host galaxy rest frame) before the neutrino alert, so that a causal connection is unlikely. The a posteriori significance of the chance detection of both the neutrinos and the SN at any epoch is 2.2 sigma within IceCube's 2011/12 data acquisition season. Also, a complementary neutrino analysis reveals no long-term signal over the course of one year. Therefore, we consider the SN detection coincidental and the neutrinos uncorrelated to the SN. However, the SN is unusual and interesting by itself: it is luminous and energetic, bearing strong resemblance to the SN IIn 2010jl, and shows signs of interaction of the SN ejecta with a dense circumstellar medium. High-energy neutrino emission is expected in models of diffusive shock acceleration, but at a low, non-detectable level for this specific SN. In this paper, we describe the SN PTF12csy and present both the neutrino and electromagnetic data, as well as their analysis.</P>

THE CONTRIBUTION OF<i>FERMI</i>-2LAC BLAZARS TO DIFFUSE TEV-PEV NEUTRINO FLUX

Aartsen, M. G.,Abraham, K.,Ackermann, M.,Adams, J.,Aguilar, J. A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Andeen, K.,Anderson, T.,Ansseau, I.,Anton, G.,Archinger, M.,Arguelles, C.,Arlen, T. C.,Auffenberg, J American Astronomical Society 2017 The Astrophysical journal Vol.835 No.1

<P>The recent discovery of a diffuse cosmic neutrino flux extending up to PeV energies raises the question of which astrophysical sources generate this signal. Blazars are one class of extragalactic sources which may produce such high-energy neutrinos. We present a likelihood analysis searching for cumulative neutrino emission from blazars in the 2nd Fermi-LAT AGN catalog (2LAC) using IceCube neutrino data set 2009-12, which was optimized for the detection of individual sources. In contrast to those in previous searches with IceCube, the populations investigated contain up to hundreds of sources, the largest one being the entire blazar sample in the 2LAC catalog. No significant excess is observed, and upper limits for the cumulative flux from these populations are obtained. These constrain the maximum contribution of 2LAC blazars to the observed astrophysical neutrino flux to 27% or less between around 10 TeV and 2 PeV, assuming the equipartition of flavors on Earth and a single power-law spectrum with a spectral index of -2.5. We can still exclude the fact that 2LAC blazars (and their subpopulations) emit more than 50% of the observed neutrinos up to a spectral index as hard as -2.2 in the same energy range. Our result takes into account the fact that the neutrino source count distribution is unknown, and it does not assume strict proportionality of the neutrino flux to the measured 2LAC gamma-ray signal for each source. Additionally, we constrain recent models for neutrino emission by blazars.</P>

Searches for small-scale anisotropies from neutrino point sources with three years of IceCube data

Aartsen, M.G.,Ackermann, M.,Adams, J.,Aguilar, J.A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Anderson, T.,Arguelles, C.,Arlen, T.C.,Auffenberg, J.,Bai, X.,Barwick, S.W.,Baum, V.,Beatty, J.J.,Becker Tjus, J. North-Holland 2015 Astroparticle physics Vol.66 No.-

<P><B>Abstract</B></P> <P>Recently, IceCube found evidence for a diffuse signal of astrophysical neutrinos in an energy range of ∼ 60 TeV to the PeV-scale [1]. The origin of those events, being a key to understanding the origin of cosmic rays, is still an unsolved question. So far, analyses have not succeeded to resolve the diffuse signal into point-like sources. Searches including a maximum-likelihood-ratio test, based on the reconstructed directions and energies of the detected down- and up-going neutrino candidates, were also performed on IceCube data leading to the exclusion of bright point sources. In this paper, we present two methods to search for faint neutrino point sources in three years of IceCube data, taken between 2008 and 2011. The first method is an autocorrelation test, applied separately to the northern and southern sky. The second method is a multipole analysis, which expands the measured data in the northern hemisphere into spherical harmonics and uses the resulting expansion coefficients to separate signal from background. With both methods, the results are consistent with the background expectation with a slightly more sparse spatial distribution, corresponding to an underfluctuation. Depending on the assumed number of sources, the resulting upper limit on the flux per source in the northern hemisphere for an <SUP> E - 2 </SUP> energy spectrum ranges from ∼ 1.5 · <SUP> 10 - 8 </SUP> GeV/cm<SUP>2</SUP> s<SUP>−1</SUP>, in the case of one assumed source, to ∼ 4 · <SUP> 10 - 10 </SUP> GeV/cm<SUP>2</SUP> s<SUP>−1</SUP>, in the case of 3500 assumed sources.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We applied two methods to search for clusters of astrophysical neutrinos on background. </LI> <LI> Investigated both hemispheres separately and three different energy spectra. </LI> <LI> Saw underfluctuation consistent with background and set limits on astrophysical flux. </LI> <LI> Compared limits to recently found astrophysical flux to constrain number of sources. </LI> <LI> Excluded few sources of very hard energy spectra for seen astrophysical flux. </LI> </UL> </P>

Characterization of the atmospheric muon flux in IceCube

Aartsen, M.G.,Abraham, K.,Ackermann, M.,Adams, J.,Aguilar, J.A.,Ahlers, M.,Ahrens, M.,Altmann, D.,Anderson, T.,Archinger, M.,Arguelles, C.,Arlen, T.C.,Auffenberg, J.,Bai, X.,Barwick, S.W.,Baum, V.,Bay North-Holland ; Elsevier Science Ltd 2016 Astroparticle physics Vol.78 No.-

<P>Muons produced in atmospheric cosmic ray showers account for the by far dominant part of the event yield in large-volume underground particle detectors. The IceCube detector, with an instrumented volume of about a cubic kilometer, has the potential to conduct unique investigations on atmospheric muons by exploiting the large collection area and the possibility to track particles over a long distance. Through detailed reconstruction of energy deposition along the tracks, the characteristics of muon bundles can be quantified, and individual particles of exceptionally high energy identified. The data can then be used to constrain the cosmic ray primary flux and the contribution to atmospheric lepton fluxes from prompt decays of short-lived hadrons. In this paper, techniques for the extraction of physical measurements from atmospheric muon events are described and first results are presented. The multiplicity spectrum of TeV muons in cosmic ray air showers for primaries in the energy range from the knee to the ankle is derived and found to be consistent with recent results from surface detectors. The single muon energy spectrum is determined up to PeV energies and shows a clear indication for the emergence of a distinct spectral component from prompt decays of short-lived hadrons. The magnitude of the prompt flux, which should include a substantial contribution from light vector meson di-muon decays, is consistent with current theoretical predictions. The variety of measurements and high event statistics can also be exploited for the evaluation of systematic effects. In the course of this study, internal inconsistencies in the zenith angle distribution of events were found which indicate the presence of an unexplained effect outside the currently applied range of detector systematics. The underlying cause could be related to the hadronic interaction models used to describe muon production in air showers. (C) 2016 Elsevier B.V. All rights reserved.</P>

Search for non-relativistic magnetic monopoles with IceCube

Aartsen, M. G.,Abbasi, R.,Ackermann, M.,Adams, J.,Aguilar, J. A.,Ahlers, M.,Altmann, D.,Arguelles, C.,Arlen, T. C.,Auffenberg, J.,Bai, X.,Baker, M.,Barwick, S. W.,Baum, V.,Bay, R.,Beatty, J. J.,Becker Springer-Verlag 2014 European Physical Journal C Vol.74 No.7