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ICECUBE LED Display [ILDm^3] is a cubic-meter, 1/1000th scale model of the IceCube Neutrino Observatory, a novel telescope that looks for nearly invisible cosmic messengers, neutrinos, using a cubic-kilometer of instrumented ice starting 1450 meters below the surface at the South Pole. The display uses art methodologies as a means for expressing imperceptible astrophysical events as sound, light and colour in the domain of the human sensorium. The experience is as aesthetically critical as it is facilitatory to an intuitive understanding of subatomic astrophysical data, leading to new ways of knowing about our Universe and its processes. The objective of this project was to build a static volumetric dis- play as a model of IceCube for visualization of spatio-temporal data recorded by the observatory. While the primary use of the display is as a model for artistic, educational, and outreach purposes, the display is also being explored as an instrument for the scientific analysis of IceCube data sets by human observers. The technical approach to designing the display was to place an emphasis on reproducibility so that it can be readily built and used by the re- searchers in the IceCube research community. Evaluation of the display is being used as a baseline for the development of future exhibits.

The next generation of the IceCube Neutrino Observatory, IceCube-Gen2, will constitute a much larger detector, increasing the rate of high-energy neutrinos. IceCube-Gen2 will address the long-standing questions about astrophysical accelerators. The experiment will also include a surface air-shower detector which will allow for measurements of cosmic rays in the energy region where a transition between Galactic and extragalactic accelerators is expected. As a baseline design for the surface detector, we consider a surface array above the optical in-ice array consisting of the same type of stations used for the IceTop enhancement, i.e., scintillation detectors and radio antennas. In order to better understand the capabilities of such an array, we performed simulations of its response to air showers, including both detector types. We will show the results of this simulation study and discuss the prospects for the surface array of IceCube-Gen2., Comment: Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06968 for all IceCube-Gen2 contributions

The recent discovery of electromagnetic signals in coincidence with gravitational waves from neutron-star mergers has solidified the importance of multimessenger campaigns for studying the most energetic astrophysical events. Pioneering multimessenger observatories, such as the LIGO/Virgo gravitational wave detectors and the IceCube neutrino observatory, record many candidate signals that fall short of the detection significance threshold. These sub-threshold event candidates are promising targets for multimessenger studies, as the information provided by these candidates may, when combined with time-coincident gamma-ray observations, lead to significant detections. In this contribution, I describe our use of sub-threshold binary neutron star merger candidates identified in Advanced LIGO's first observing run (O1) to search for transient events in very-high-energy gamma rays using archival observations from the VERITAS imaging atmospheric Cherenkov telescope array. I describe the promise of this technique for future joint sub-threshold searches.

37. International Cosmic Ray Conference, ICRC 2021, Berlin, Germany, 15 Jul 2021 - 22 Jul 2021; Proceedings of Science 395, 225 (2022). doi:10.22323/1.395.0225 special issue: "37th International Cosmic Ray Conference : ICRC2021 : 12-23 July 2021 : Berlin, Germany - Online / Editorial Board: Alexander Kappes, Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany ; Bianca Keilhauer, Karlsruhe Institute of Technology, Institute for Astroparticle Physics (IAP)", Published by SISSA, Trieste

The flux of high-energy neutrinos passing through the Earth is attenuated due to their interactions with matter. The interaction rate is modulated by the neutrino interaction cross section and affects the flux arriving at the IceCube Neutrino Observatory, a cubic-kilometer neutrino detector embedded in the Antarctic ice sheet. We present a measurement of the neutrino cross section between 60 TeV and 10 PeV using the high-energy starting events (HESE) sample from IceCube with 7.5 years of data. The result is binned in neutrino energy and obtained using both Bayesian and frequentist statistics. We find it compatible with predictions from the Standard Model. Flavor information is explicitly included through updated morphology classifiers, proxies for the the three neutrino flavors. This is the first such measurement to use the three morphologies as observables and the first to account for neutrinos from tau decay., Comment: 10 pages, 7 figures, 2 tables. This article is supported by a long-form paper that discusses in high-energy starting event selection titled: "The IceCube high-energy starting event sample: Description and flux characterization with 7.5 years of data"

The IceCube Neutrino Observatory at the geographic South Pole instruments a gigaton of glacial Antarctic ice with over 5000 photosensors. The detector, by now running for over a decade, will be upgraded with seven new densely instrumented strings. The project focuses on the improvement of low-energy and oscillation physics sensitivities as well as re-calibration of the existing detector. Over the last few years we developed a Precision Optical Calibration Module (POCAM) providing self-monitored, isotropic, nanosecond, light pulses for optical calibration of large-volume detectors. Over 20 next-generation POCAMs will be calibrated and deployed in the IceCube Upgrade in order to reduce existing detector systematics. We report a general overview of the POCAM instrument, its performance and calibration procedures., Comment: Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06966 for all IceCube contributions

The IceCube Neutrino Observatory, located at the geographic South Pole, is the world's largest neutrino telescope, instrumenting 1 km$^3$ of Antarctic ice with 5160 photosensors to detect Cherenkov light. For the IceCube Upgrade, to be deployed during the 2022-23 polar field season, and the enlarged detector IceCube-Gen2 several new optical sensor designs are under development. One of these optical sensors, the Wavelength-shifting Optical Module (WOM), uses wavelength-shifting and light-guiding techniques to measure Cherenkov photons in the UV range from 250 nm to 380 nm. In order to understand the potential gains from this new technology, a measurement of the scattering and absorption lengths of UV light was performed in the SPICEcore borehole at the South Pole during the winter seasons of 2018/2019 and 2019/2020. For this purpose, a calibration device with a UV light source and a detector using the wavelength shifting technology was developed. We present the design of the developed calibration device, its performance during the measurement campaigns, and the comparison of data to a Monte Carlo simulation., Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06966 for all IceCube contributions

37. International Cosmic Ray Conference, ICRC 2021, Berlin, Germany, 15 Jul 2021 - 22 Jul 2021; Proceedings of Science 395, 1133 (2022). doi:10.22323/1.395.1133 special issue: "37th International Cosmic Ray Conference : ICRC2021 : 12-23 July 2021 : Berlin, Germany - Online / Editorial Board: Alexander Kappes, Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany ; Bianca Keilhauer, Karlsruhe Institute of Technology, Institute for Astroparticle Physics (IAP)", Published by SISSA, Trieste

We demonstrate that a population of active galactic nuclei (AGN) can describe the observed spectrum of ultra-high-energy cosmic rays (UHECRs) at and above the ankle, and that the dominant contribution comes from low-luminosity BL Lacertae objects. An additional, subdominant contribution from high-luminosity AGN is needed to improve the description of the composition observables, leading to a substantial neutrino flux that peaks at exaelectronvolt (EeV) energies. We also find that different properties for the low- and high-luminosity AGN populations are required; a possibly similar baryonic loading can already be excluded from current IceCube Neutrino Observatory observations. We also show that the flux of neutrinos emitted from within the sources should outshine the cosmogenic neutrinos produced during the propagation of UHECRs. This result has profound implications for the ultra-high-energy ($\ensuremath{\sim}\mathrm{EeV}$) neutrino experiments, since additional search strategies can be used for source neutrinos compared to cosmogenic neutrinos, such as stacking searches, flare analyses, and multimessenger follow-ups.

DarkCapPy is a Python 3/Jupyter package for calculating rates associated with dark matter capture in the Earth, annihilation into light mediators, and the subsequent observable decay of the light mediators near the surface of the Earth. The package includes a calculation of the Sommerfeld enhancement at the center of the Earth and the timescale for capture--annihilation equilibrium. The code is open source and can be modified for other compact astronomical objects and mediator spins., 25 pages, 5 figures. Accompanying GitHub package: http://github.com/agree019/DarkCapPy

The origin of cosmic rays is one of the most important questions in modern astrophysics. Leading world observatories are engaged in their search in our Galaxy and beyond. Current observations of bright sources of hard X-rays and gamma radiation require precise models of cosmic-ray accelerators and emission generation. Recent detection of astrophysical neutrinos with the energy exceeding 1015 eV achieved by the IceCube Neutrino Observatory and registration by the LOFAR observatory of the light cosmic-ray component at 1016–1017 eV have given rise to a wide discussion of whether its sources are galactic or extragalactic. H.E.S.S. observations of high-energy gamma-ray sources in compact massive clusters Westerlund 1 and Cl*1806-20 triggered a new search for the models of effective accelerators of high-energy cosmic rays, socalled galactic PeVatrons. In this paper, the properties of compact massive young stellar clusters as possible sources of cosmic rays, neutrinos, and gamma emission are discussed. We suppose that an expanding supernova remnant in a compact massive cluster is an effective cosmic-ray accelerator up to the energies of 1015 eV and beyond. Energy spectra of particles being accelerated in the system of colliding shocks generated by a supernova remnant interaction with nearby stellar winds have a broken power-law shape with a strong upturn around several teraelectronvolts and a cutoff energy at tens of petaelectronvolts. These sources provide the maximal emission flux at the maximal energies of the spectrum. Teraelectronvolt sources detected by H.E.S.S. could be related to supernova remnants in Westerlund 1 and Cl*1806-20 and be responsible for the 10% of the IceCube neutrino events. We have also shown that PeVatrons in the systems of colliding shocks can provide up to 80% of the light cosmic-ray component at the energies of 1016–1017 eV detected at the Earth.

Measurements of neutrinos at and below 10 GeV provide unique constraints of neutrino oscillation parameters as well as probes of potential Non-Standard Interactions (NSI). The IceCube Neutrino Observatory's DeepCore array is designed to detect neutrinos down to GeV energies. IceCube has built the world's largest data set of neutrinos >10 GeV, making searches for NSI a computational challenge. This work describes the use of convolutional neural networks (CNNs) to improve the energy reconstruction resolution and speed of reconstructing O(10 GeV) neutrino events in IceCube. Compared to current likelihood-based methods which take seconds to minutes, the CNN is expected to provide approximately a factor of 2 improvement in energy resolution while reducing the reconstruction time per event to milliseconds, which is essential for processing large datasets., Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06966 for all IceCube contributions. 8 pages. 16 figures

The IceCube Neutrino Observatory has detected high-energy astrophysical neutrinos in the TeV-PeV range. These neutrinos have an isotropic distribution on the sky, and therefore, likely originate from extragalactic sources. Active Galactic Nuclei form a class of astronomical objects which are promising neutrino source candidates given their high electromagnetic luminosity and potential ability to accelerate cosmic rays up to energies greater than 10$^{16}$ eV. Interactions of these cosmic rays within the AGN environment are expected to produce both neutrinos and pionic gamma rays. Some hadronic models of AGN emission suggest that such gamma rays can in turn interact with the dense photon fields of AGN and cascade down to hard X-rays and MeV gamma rays. We present an update on the IceCube stacking analysis searching for high-energy neutrinos from hard X-ray sources sampled from the $\textit{Swift}$-BAT AGN Spectroscopic Survey., Comment: Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06966 for all IceCube contributions, 11 pages, 5 figures

The Glashow resonance describes the resonant formation of a W− boson during the interaction of a high-energy electron antineutrino with an electron1, peaking at an antineutrino energy of 6.3 petaelectronvolts (PeV) in the rest frame of the electron. Whereas this energy scale is out of reach for currently operating and future planned particle accelerators, natural astrophysical phenomena are expected to produce antineutrinos with energies beyond the PeV scale. Here we report the detection by the IceCube neutrino observatory of a cascade of high-energy particles (a particle shower) consistent with being created at the Glashow resonance. A shower with an energy of 6.05 ± 0.72 PeV (determined from Cherenkov radiation in the Antarctic Ice Sheet) was measured. Features consistent with the production of secondary muons in the particle shower indicate the hadronic decay of a resonant W− boson, confirm that the source is astrophysical and provide improved directional localization. The evidence of the Glashow resonance suggests the presence of electron antineutrinos in the astrophysical flux, while also providing further validation of the standard model of particle physics. Its unique signature indicates a method of distinguishing neutrinos from antineutrinos, thus providing a way to identify astronomical accelerators that produce neutrinos via hadronuclear or photohadronic interactions, with or without strong magnetic fields. As such, knowledge of both the flavour (that is, electron, muon or tau neutrinos) and charge (neutrino or antineutrino) will facilitate the advancement of neutrino astronomy., SCOPUS: ar.j, info:eu-repo/semantics/published

Clusters of galaxies can potentially produce cosmic rays (CRs) up to very-high energies via large-scale shocks and turbulent acceleration. Due to their unique magnetic-field configuration, CRs with energy $\leq 10^{17}$ eV can be trapped within these structures over cosmological time scales, and generate secondary particles, including neutrinos and gamma rays, through interactions with the background gas and photons. In this work, we compute the contribution from clusters of galaxies to the diffuse neutrino background. We employ three-dimensional cosmological magnetohydrodynamical simulations of structure formation to model the turbulent intergalactic medium. We use the distribution of clusters within this cosmological volume to extract the properties of this population, including mass, magnetic field, temperature, and density. We propagate CRs in this environment using multi-dimensional Monte Carlo simulations across different redshifts (from $z \sim 5$ to $z =0$), considering all relevant photohadronic, photonuclear, and hadronuclear interaction processes. We find that, for CRs injected with a spectral index $\alpha = 1.5 - 2.7$ and cutoff energy $E_\text{max} = 10^{16} - 5\times10^{17} \; \text{eV}$, clusters contribute to a sizeable fraction to the diffuse flux observed by the IceCube Neutrino Observatory, but most of the contribution comes from clusters with $M \gtrsim 10^{14} \; M_{\odot}$ and redshift $ z \lesssim 0.3$. If we include the cosmological evolution of the CR sources, this flux can be even higher., Comment: 14 pages, 31 figures, journal paper

The IceCube detector is a multipurpose neutrino observatory located at the South Pole. With an instrumented volume of a cubic kilometer, IceCube can detect neutrino fluxes from all flavors in the GeV - PeV energy range. In the recent years IceCube has heralded the birth of neutrino astronomy with the discovery of an astrophysical neutrino flux. Besides its astrophysical program IceCube is also at the forefront of indirect searches for dark matter and physics beyond the standard model. In this contribution I will review the latest results of IceCube as a particle physics detector

Many concepts in astrophysics research can be difficult for a lay individual to understand or to comprehend their importance. One such example concept is the IceCube Neutrino Observatory, which detects high-energy neutrinos at the South Pole in Antarctica. The observatory uses information from detected neutrinos originating deep in outer space to better understand astrophysical phenomena like black holes or exploding stars. Unfortunately, it is often difficult for the public to understand how these pieces fit together towards creating a more complete understanding of our universe. In means of creating a novel point of engagement around these learning concepts, an interactive exhibit was created which used large multi-touch screen and Virtual Reality (VR) equipment. The exhibit, placed in a public environment, was evaluated both formally and informally around its effectiveness of providing STEM learning opportunities. The results show that the system not only provided an effective means of conveying content, but also provided a means of sparking the curiosity of users to learn more about the presented subject matter. Further results show that outcomes demonstrated significant differences between the two deployed devices and subject populations. Based on these findings, guidelines are offered for others who aim to deploy similar systems in publicly accessible spaces.

We present constraints on an astrophysical population of neutrino sources imposed by recent data from the IceCube neutrino observatory. By using the IceCube point source search method to model the detection of sources, our detection criterion is more sensitive than using the observation of high-energy neutrino multiplets for source identification. We frame the problem as a Bayesian hierarchical model to connect the high-level population parameters to the IceCube data, allowing us to consistently account for all relevant sources of uncertainty in our model assumptions. Our results show that sources with a local density of $n_0 \gtrsim 10^{-7}$ $\rm{Mpc}^{-3}$ and luminosity $L \lesssim 10^{43}$ erg/s are the most likely candidates, but that populations of rare sources with $n_0 \simeq 10^{-9}$ $\rm{Mpc}^{-3}$ and $L \simeq 10^{45}$ erg/s can still be consistent with the IceCube observations. We demonstrate that these conclusions are strongly dependent on the source evolution considered, for which we consider a wide range of models. In doing so, we present realistic, model-independent constraints on the population parameters that reflect our current state of knowledge from astrophysical neutrino observations. We also use our framework to investigate constraints in the case of possible source detections and future instrument upgrades. Our approach is flexible and can be used to model specific source cases and extended to include multi-messenger information., Comment: Update to address erratum published at DOI: 10.1103/PhysRevD.105.129904. Code available online at https://github.com/cescalara/nu_pop

The IceCube Neutrino Observatory observes neutrinos interacting deep within the South Pole ice. It consists of 5,160 digital optical modules embedded within a cubic kilometer of ice, over depths of 1,450 m to 2,450 m. At the lower center of the array is the DeepCore subdetector. Its denser sensor configuration lowers the observable energy threshold to the GeV-scale, facilitating the study of atmospheric neutrino oscillations. The precise reconstruction of neutrino direction is critical in the measurements of oscillation parameters. This work presents a method to reconstruct the zenith angle of GeV-scale events in IceCube by using a convolutional neural network and compares the result to that of the current likelihood-based reconstruction algorithm., Comment: Presented at the 37th International Cosmic Ray Conference (ICRC 2021). See arXiv:2107.06966 for all IceCube contributions. 8 pages

The IceCube Neutrino Observatory is a cubic-kilometer neutrino telescope located at the geographic South Pole. Buried deep under the Antarctic ice sheet, an array of 5160 Digital Optical Modules (DOMs) is used to capture the Cherenkov light emitted by relativistic particles generated from neutrino interactions. The main goal of IceCube is the detection of astrophysical neutrinos. In 2013 the IceCube neutrino telescope discovered a high-energy diffuse flux of neutrino events with energy ranging from tens of TeV up to few PeV of cosmic origin. Meanwhile, different analyses confirm the discovery and search for possible correlations with astrophysical sources. However, the source of these neutrinos remains a mystery, since no counterparts have been identified yet. In this contribution we give an overview of the detection principles of IceCube, the most recent results, and the plans for a next-generation neutrino detector, dubbed IceCube-Gen2.

The IceCube Neutrino Observatory features approximately a cubic-kilometer volume of instrumented ice at the geographic South Pole. A high energy astrophysical neutrino flux has been observed, initially in 2013, as an excess of neutrinos above 10 TeV compared to the expectation from an atmospheric neutrino background. This signal, nowadays significant at >6 σ, has been observed both in neutrino interactions starting in the detector volume and in throughgoing muons generated in charged-current muon neutrino interactions outside the detector. No astrophysical objects have yet been identified as the flux source, which is currently consistent with an isotropic expectation. This paper reviews the evidence for the astrophysical flux and the status of the search for its sources. It also presents a discussion of proposed detector extensions being designed to solve the mystery of the astrophysical neutrino origin.

IceCube-Gen2 is a future large-scale extension to the IceCube Neutrino Observatory, a cubic-kilometer-scale neutrino detector at the geographic South Pole. The IceCube data acquisition system architecture, while running stably with over 99% uptime, will be re-optimized for IceCube-Gen2 to solve design challenges with power consumption, communications bandwidth, and cable specifications. In particular, we describe how distribution of the photomultiplier tube signal digitization and pre-trigger storage can reduce power and bandwidth requirements. Additional changes to IceCube's custom communications protocol can also relax crosstalk requirements on the copper cabling. We report on the status of these optimizations in the prototype Gen2 digital optical module design for the upcoming IceCube Upgrade.

Galactic sites of acceleration of cosmic rays to energies of order 10^15 eV and higher, dubbed PeVatrons, reveal themselves by recently discovered gamma radiation of energies above 100 TeV. However, joint gamma-ray and neutrino production, which marks unambiguously cosmic-ray interactions with ambient matter and radiation, was not observed until now. In November 2020, the IceCube neutrino observatory reported an ~150 TeV neutrino event from the direction of one of the most promising Galactic PeVatrons, the Cygnus Cocoon. Here we report on the observation of a 3.1-sigma (post trial) excess of atmospheric air showers from the same direction, observed by the Carpet-2 experiment and consistent with a few-months flare in photons above 300 TeV, in temporal coincidence with the neutrino event. The fluence of the gamma-ray flare is of the same order as that expected from the neutrino observation, assuming the standard mechanism of neutrino production. This is the first evidence for the joint production of high-energy neutrinos and gamma rays in a Galactic source., 7 pages, 3 figures, AASTeX. V2: minor changes; Appendix with more analysis details added. Version accepted by Astrophys. J. Letters. V3: title corrected (text unchanged), matches the published version

The recent results of IceCube Neutrino Observatory include an excess of PeV neutrino events which appear to follow a broken power law different from the other lower energy neutrinos detected by IceCube. The possible astrophysical source of these neutrinos is still unknown. One possible source of such neutrinos could be the decay of non-thermal, long-living heavy mass Dark Matter, whose mass should be $> 10^{6} \rm {GeV}$ and could have produced at the very early Universe. They can undergo cascading decay via both hadronic and leptonic channels to finally produce such high energy neutrinos. This possibility has been explored in this work by studying the decay flux of these Dark Matter candidates. The mass and lifetime of such Dark Matter particles have been obtained by performing a $��^2$ fit with the PeV neutrino data of IceCube. We finally estimate the baryon asymmetry produced in the Universe due to such Dark Matter decay., 25 pages, 7 figures

Following the detection of high-energy astrophysical neutrinos in 2013, their origin is still unknown. Aiming for the identification of an electromagnetic counterpart of a rapidly fading source, we have implemented a realtime analysis framework for the IceCube neutrino observatory. Several analyses selecting neutrinos of astrophysical origin are now operating in realtime at the detector site in Antarctica and are producing alerts to the community to enable rapid follow-up observations. The goal of these observations is to locate the astrophysical objects responsible for these neutrino signals. This paper highlights the infrastructure in place both at the South Pole detector site and at IceCube facilities in the north that have enabled this fast follow-up program to be developed. Additionally, this paper presents the first realtime analyses to be activated within this framework, highlights their sensitivities to astrophysical neutrinos and background event rates, and presents an outlook for future discoveries., Comment: 33 pages, 9 figures, Published in Astroparticle Physics

This paper contends that a robust concept of the technosphere – indeed one that is truly adequate to the Anthropocene – must be approached using a plurality of methods that do not categorize agencies or rely on hierarchical scalar analysis. In this commentary, we draw from feminist science studies scholar Karen Barad’s philosophy of agential realism, and in particular her concept of ‘intra-action’, to identify the technosphere as emergent from entangled practices, sites and infrastructures, and to trace the technosphere from the ‘meso’ scale to subatomic and cosmological realms of force and energy. We demonstrate the value of a critical, intra-active approach to technical assemblages by thinking the technosphere concept with and within a vast experimental apparatus: the IceCube Neutrino Observatory.

Almost 4 billion years ago, a brilliantly bright galaxy fired a burst of lightweight, fast-moving particles toward Earth (1). Now, an observatory at the South Pole has traced those particles back to their source, potentially solving a century-old mystery about the waves of radiation produced somewhere outside the solar system that wash over our planet each day. But researchers will have to continue to examine the proposed source in multiple wavelengths to ensure they’ve identified the culprit. Researchers at the IceCube Neutrino Observatory, launched in 2002, have for the first time been able to trace some of the most energetic neutrinos back to their purported source, the blazar TXS 0506+056. Image courtesy of National Science Foundation/IceCube. Neutrinos are born from some of the most violent events in the universe, including explosive supernovae and the chaotic environment around supermassive black holes. Tracing neutrinos back to their source can help scientists better understand these destructive events. Deep in the ice of Antarctica, the IceCube Neutrino Observatory, launched in 2002, hunts for neutrinos, subatomic particles so weak that they usually pass through normal matter undetected (see www.pnas.org/content/111/24/8699). Every second, roughly 100 billion neutrinos pass through 1 square centimeter on Earth, flying at nearly the speed of light. Many of them come from the sun. But the more powerful neutrinos are created outside of the galaxy, generated by a process researchers have only speculated about. For the first time, researchers have been able to trace some of the most energetic particles back to their source, the blazar TXS 0506+056. One of the top suspects in the formation of neutrinos, blazars are a class of active galaxy nuclei (AGNs) that form from a supermassive black hole. Although the black hole devours most of the material around it, some of the gas and dust is deflected …

We propose a new way to probe non-standard interactions (NSI) of neutrinos with matter using the ultra-high energy (UHE) neutrino data at current and future neutrino telescopes. We consider the Zee model of radiative neutrino mass generation as a prototype, which allows two charged scalars -- one $SU(2)_L$-doublet and one singlet, both being leptophilic, to be as light as 100 GeV, thereby inducing potentially observable NSI with electrons. We show that these light charged Zee-scalars could give rise to a Glashow-like resonance feature in the UHE neutrino event spectrum at the IceCube neutrino observatory and its high-energy upgrade IceCube-Gen2, which can probe a sizable fraction of the allowed NSI parameter space., 7 pages, 2 figures; minor changes and added references, version to appear in Phys. Rev. Lett

IceCube Neutrino Observatory is a cubic kilometer neutrino detector located at the South Pole designed to detect high-energy astrophysical neutrinos. To thoroughly understand the detected neutrinos and their properties, the detector response to simulated signal and background has to be modeled using Monte Carlo techniques. An integral part of these studies are the optical properties of the ice the observatory is built into. The propagation of individual photons from particles produced by neutrino interactions in the ice can be greatly accelerated using graphics processing units (GPUs). In this paper, we will describe how we perform the photon propagation and create a global pool of GPU resources for both production and individual users.

The IceCube Neutrino Observatory at the geographic South Pole has reached a number of milestones in the field of neutrino astrophysics. The achievements of IceCube include the discovery of a high-energy astrophysical neutrino flux, and the temporal and directional correlation of neutrinos with a flaring blazar. The IceCube Upgrade, which will be constructed in the 2022/23 Antarctic Summer season, is the next stage of the IceCube project. The IceCube Upgrade consists of seven new columns of photosensors, densely embedded near the bottom center of the existing cubic-kilometer-scale IceCube Neutrino Observatory. An improved atmospheric neutrino event selection efficiency and reconstruction at a few GeV can be achieved with the dense infill of the Upgrade's photosensor array. The Upgrade will provide world-leading sensitivity to neutrino oscillations and will enable IceCube to take unique measurements of tau neutrino appearance with a high precision. Furthermore, the new array will also improve the existing IceCube detector. The Upgrade strings will include new calibration devices designed to deepen the knowledge of the optical properties of glacial ice and the detector response. The improved calibration resulting from the Upgrade will be applied to the entire archive of IceCube data collected over the last 10 years, improving the angular and spatial resolution of the detected astrophysical neutrino events. Finally, the Upgrade represents the first stage in the development of IceCube-Gen2, the next-generation neutrino telescope at the South Pole., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

The IceCube neutrino observatory is a 3D array of photodetectors installed in the Antarctic ice. It consists of 5,160 photomultiplier-tubes spread among 86 vertical strings making a total detector volume of more than a cubic kilometer. It detects neutrinos via Cherenkov light of charged relativistic particles from neutrino interactions with the detector volume. IceCube is, due to its size and photosensor spacing, particularly sensitive to high-energy neutrinos. In this analysis we search for dark matter that annihilates into a metastable mediator that subsequently decays into Standard Model particles. These models yield an enhanced high-energy neutrino flux from dark matter annihilation inside the Sun compared to models without a mediator. Neutrino signals that are produced directly inside the Sun are strongly attenuated at higher energies due to interactions with the solar plasma. In the models considered here, the mediator can escape the Sun before producing any neutrinos, thereby avoiding attenuation. IceCube is ideal to search for this enhanced high-energy neutrino signal. We present the sensitivities of an analysis of six years of IceCube data looking for dark matter in the Sun considering mediator lifetimes between 1 ms to 10 s and dark matter masses between 200 GeV and 10 TeV. We show that IceCube is sensitive to spin--dependent cross--sections of $3.45 \times 10^{-34}~\rm cm^2$ for dark matter masses of 1 TeV.

The shadowing effect of the Moon and Sun in TeV cosmic rays has been measured with high statistical significance by several experiments. Unlike particles from directions close to the Moon, however, charged particles passing by the neighborhood of the Sun are affected not only by the geomagnetic but also by the solar near- and interplanetary-magnetic field. Since the latter undergoes a well-known 11-year cycle -- during which it can become highly disordered -- the cosmic-ray shadow cast by the Sun as observed on Earth is expected to change over time. We present an update of the analysis of the cosmic-ray Moon and Sun shadows using data taken with the IceCube Neutrino Observatory. With a median energy after quality cuts of approximately $50-60\,$TeV, depending on the cosmic-ray flux model used, primary cosmic rays inducing events which pass IceCube's Sun shadow filter have a comparatively high energy. While the results for the Moon shadow confirm the stability of the IceCube observatory, the results for the Sun shadow exhibit a clear variation correlating with solar activity and theoretical models of the solar magnetic field., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

The Astrophysical Multimessenger Observatory Network (AMON) has been working to link the world's high-energy and multimessenger observatories together into a single network in order to evoke discovery of multimessenger sources, exploit these sources for purposes of astrophysics, fundamental physics, and cosmology, and explore project datasets for evidence of multimessenger source populations. AMON has been working to commission multiple multimessenger alert streams, including gravitational wave + gamma-ray (GW+$\gamma$) and high energy neutrino + gamma-ray ($\nu$+$\gamma$) coincidence alerts. One such $\nu$+$\gamma$ alert stream, now in an advanced stage of development, will search in near real-time for statistically-rare coincidences between $\sim$TeV gamma-rays observed by the High-Water Altitude Cherenkov Observatory (HAWC) and $\geqslant$TeV neutrinos detected by the IceCube Neutrino Observatory. We describe the statistical design, calibration, and validation of these HAWC and IceCube $\nu$+$\gamma$ alerts, which will be commissioned soon and made available to AMON follow-up partners under terms of the AMON MoU. With a median delay to alert distribution of six hours and angular uncertainties of $\leqslant$1\arcdeg, the alerts should be well-suited for deep electromagnetic follow-up observations.

The IceCube Neutrino Observatory at the geographic South Pole consists of two components, a km2 surface array IceTop and a km3 in-ice array between 1.5 and 2.5 km below the surface. Cosmic ray events with primary energy above a few tens of TeV may trigger both the IceTop and in-ice array and leave a three-dimensional footprint of the electromagnetic and muonic components in the extensive air shower. A new reconstruction based on the minimization of a unified likelihood function involving quantities measured by both IceTop and in-ice detectors was developed. This report describes the new reconstruction algorithm and summarizes its performance tested with Monte Carlo events under two different containment conditions. The advantages of the new reconstruction are discussed in comparison with reconstructions that use IceTop or in-ice data separately. Some possible improvements are also summarized., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

Located at the South Pole, the IceCube Neutrino Observatory is the world largest neutrino telescope, instrumenting one cubic kilometre of Antarctic ice at a depth between 1450m to 2450m. In 2013 IceCube reported the first observations of a diffuse astrophysical high-energy neutrino flux. Although the IceCube Collaboration has identified more than 100 high-energy neutrino events, the origin of this neutrino flux is still not known. Blazars, a subclass of Active Galactic Nuclei and one of the most powerful classes of objects in the Universe, have long been considered promising sources of high energy neutrinos. A blazar origin of this high-energy neutrino flux can be examined using stacking methods testing the correlation between IceCube neutrinos and catalogs of hypothesized sources. Here we present the results of a stacking analysis for 1301 blazars from the third catalog of hard \textit{Fermi}-LAT sources (3FHL). The analysis is performed on 8 years of through-going muon data from the Northern Hemisphere, recorded by IceCube between 2009 and 2016. No excess of neutrinos from the blazar position was found and first limits on the neutrino production of these sources will be shown., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

The IceCube Neutrino observatory has discovered an astrophysical neutrino flux in the energy range >1 TeV with their highest energy event ~3 PeV. Although IceCube has excellent muon flavor identification, their ability to identify tau neutrinos is highly limited. We present a concept for observing the tau neutrino flux in the 1-100 PeV range, where a flux is guaranteed and its observation would give further support to the astrophysical origin of the IceCube flux. The design of the observatory requires an acceptance hA?i >400 m2 sr×( PeVE )1.5 to match the ~1 PeV IceCube all-flavor event rate in tau neutrinos provided a ?e: ?µ: ?t = 1: 1: 1 flavor ratio. The energy dependence of the acceptance is designed to match the IceCube best-fit spectral flux index of E-2.5 so the spectrum is evenly sampled in the 1-100 PeV range. We present a background-free implementation with pointing resolution < 1? to begin the era of high energy tau neutrino astronomy.

International audience; The analysis of the ANTARES all-flavour 9-year data sample provided the observation of a mild excess of events over the expected atmospheric backgrounds. This excess is consistent with the high-energy diffuse cosmic neutrino signal detected by the IceCube Neutrino Observatory, using different analysis strategies and data sample, though less significant because of the smaller detector size. Nevertheless, the analysis of ANTARES data can provide valuable information in the study of the high-energy neutrino signal. The data sample of the previously published analysis has been expanded adding ∼900 additional days of detector data acquisition time. The results of the analysis of this additional set are reported in this contribution. A 1.8σ excess above the expectations from atmospheric backgrounds is observed in data. The null-cosmic contribution in the high-energy sample is excluded at 90% confidence level.

The IceCube Neutrino Observatory detects atmospheric muon neutrinos above 100 GeV at a rate of about 100 000 per year. These neutrinos originate from decays of charged pions and kaons in cosmic ray air showers. Their flux depends on the probability of production and decay of the parent mesons, and is thus sensitive to the stratospheric temperature. Neutrino rates from 8 years of operation of the detector are correlated with the atmospheric temperature profile as measured by the Atmospheric Infrared Sounder (AIRS). An analysis of this correlation provides a test of models of hadronic interactions in atmospheric air showers. This analysis of neutrinos complements the analysis of the correlation of atmospheric muons with temperature that is presented in another paper at this conference., Comment: Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

The IceCube Neutrino Observatory is the world's largest neutrino detector, instrumenting a cubic kilometer of ice at the geographic South Pole. The detector probes neutrino energies from GeV to PeV, and collects high statistics neutrino samples by virtue of its extremely large volume. IceCube was designed to detect high-energy neutrinos from potential cosmic ray acceleration sites such as active galactic nuclei, gamma ray bursts and supernova remnants. IceCube announced the detection of a diffuse flux of astrophysical neutrinos in 2013, including the highest energy neutrinos ever detected. IceCube has since developed a robust system of realtime alerts generated by astrophysical neutrino candidates that trigger rapid follow-up observations by other telescopes and detectors. In September 2017, IceCube observed a neutrino in coincidence with a flaring blazar, signaling the era of neutrino astronomy and widening the field of multi-messenger astronomy. The IceCube science program extends beyond multi-messenger astronomy to include the fundamental physics of neutrino oscillations and neutrino interactions with matter, cosmic ray physics, and searches for particles and forces beyond the Standard Model. This talk will cover the latest neutrino physics and astrophysics results from IceCube and future prospects for the detector.

36th International Cosmic Ray Conference, ICRC2019, Madison, WI, USA, 24 Jul 2019 - 1 Aug 2019; Proceedings of Science 358, 855 pp. (2019)., Following the first observation of an astrophysical high-energy neutrino flux with the IceCubeNeutrino Observatory in 2013 and the identification of a first cosmic high-energy neutrinosource in 2017, the detector will be upgraded with about 700 new advanced optical sensors.This will expand IceCube’s capabilities both at low and high neutrino energies. A large fractionof the upgrade modules will be multi-PMT Digital Optical Modules, mDOMs, each featuring24 three-inch class photomultiplier tubes (PMTs) pointing uniformly in all directions, therebyproviding an almost homogeneous angular coverage. The signal from each PMT is digitizedindividually, providing directional information for the incident photons. Together, the 24 PMTsprovide an effective photosensitive area more than twice than that of the current IceCube opticalmodule. The main mDOM design challenges arise from the constraints on the module size andpower needed for the 24-channel high-voltage and readout systems. This contribution presentsan mDOM design that meets these challenges and discusses the sensitivities expected from thesemodules.

Dark matter particles in the galactic halo can scatter off particles in celestial bodies such as stars or planets, lose energy and become gravitationally trapped. In this process, an accumulation of dark matter in the center of celestial bodies is expected, for example, at the center of the Earth. If dark matter self-annihilates into Standard Model particles, the end products of these annihilations include neutrinos. The IceCube Neutrino Observatory at the geographic South Pole can detect the resulting flux of neutrinos originating from dark matter annihilation in the center of the Earth. A search for this signal is on-going using 8 years of IceCube data and probing different annihilation channels. Here the sensitivities are presented for this new analysis, showing significant improvements with respect to the previous analyses from IceCube and other experiments.

The ANTARES neutrino telescope, located in the Mediterranean Sea, and the IceCube neutrino observatory, located at the geographic South Pole, both search for cosmic neutrino events with an instantaneous full-sky field of view. The different characteristics of the two telescopes, in particular the larger instrumented volume of IceCube and the better visibility towards the Southern Sky for neutrino energies below 100 TeV of ANTARES, are exploited in a combined search for point-like and extended sources. The sensitivity to neutrino sources located in the Southern Sky is improved by a factor of $\sim$2 compared to individual studies. The data samples used in this analysis correspond to all track-like and shower-like events from the direction of the Southern Sky which were included in the nine-year ANTARES point-source analysis, combined with the through-going track-like events used in the seven-year IceCube point-source search. In this analysis, the Southern Sky is scanned for possible excesses of neutrinos that might indicate the presence of a source, while the coordinates of predefined candidate neutrinos sources are also evaluated in order to limit the penalty of trials. In addition, special focus is given to the region around the Galactic Centre, treated as an extended neutrinos source, and to the location of the supernova remnant RXJ 1713.7-3946. The result of this combined search for galactic and extra-galactic neutrino sources in the Southern Sky is reported here. No significant evidence of cosmic neutrino sources is found and flux upper limits from the various searches are presented.

Multi-messenger searches for gravitational waves and high-energy neutrinos provide important insights into the dynamics of and particle acceleration by black holes and neutron stars. With LIGO's third observing period (O3), the number of gravitational wave detections has been substantially increased. The rapid identification of joint signals is crucial for electromagnetic follow-up observations of transient emission that is only detectable for short periods of time. High-energy neutrino direction can be reconstructed to sub-degree precision, making a joint detection far better localized than a standalone gravitational-wave signal. We present the latest sensitivity of joint searches and discuss the Low-Latency Algorithm for Multi-messenger Astrophysics (LLAMA) that combines LIGO/Virgo gravitational-wave candidates and searches in low-latency for coincident high-energy neutrinos from the IceCube Neutrino Observatory. We will further discuss future prospects of joint searches from the perspective of better understanding the interaction of relativistic and sub-relativistic outflows from binary neutron star mergers., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

The IceCube Neutrino Observatory features both a kilometer-cubed detector between 1.45 and 2.45 km depth and an array of ice-filled tanks, called IceTop, located at the surface. The presence of both detectors at the same location allows for detailed studies of cosmic rays and their muon content in ice, while the lack of signals in the surface detectors can be used to identify muon tracks in the deep detector as neutrino candidates and to determine the veto efficiency of IceTop. While the solid angle coverage of the current detectors is limited, this has interesting implications for the design of a larger surface array. In this contribution, we present the results from this study applied to 5 years of data. We find a few interesting neutrino candidate events that pass the cuts designed to veto cosmic rays. Thorough simulations are necessary to establish the likelihood for these events to be astrophysical neutrinos or rare cosmic rays., Comment: Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions. 8 pages, 8 figures

The era of multimessenger astrophysics has arrived with the simultaneous operation of large cosmic-ray, gamma-ray, neutrino, and gravitational-wave observatories. In just the past two years, an electromagnetic (EM) counterpart was detected for a gravitational wave event, and evidence for an EM counterpart of high energy neutrinos has been identified. These measurements have had a major impact on our view of the non-thermal universe, but understanding cosmic accelerators require a substantial increase in the number of multimessenger observations. The Astrophysical Multimessenger Observatory Network (AMON) is designed for high-statistics searches of sub-threshold transient alerts from gamma-ray and neutrino detectors. Within AMON, we have implemented a joint-likelihood analysis of TeV gamma-ray measurements from the High Altitude Water Cherenkov (HAWC) Observatory and neutrinos from the IceCube Neutrino Observatory. AMON is ready to produce real-time coincidence alerts using HAWC ``hotspots'' and IceCube astrophysical neutrino events. These alerts will be distributed to AMON follow-up partners with a median anticipated delay of six hours, which corresponds to a full transit in the field of view of HAWC. The alerts will have an angular resolution of ${\sim} 0.2^{\circ}$, making them well- suited for deep electromagnetic follow-up observations.

Physical review / D 88(4), 042004 (2013). doi:10.1103/PhysRevD.88.042004, We report on the measurement of the all-particle cosmic ray energy spectrum with the IceTop air shower array in the energy range from 1.58 PeV to 1.26 EeV. The IceTop air shower array is the surface component of the IceCube Neutrino Observatory at the geographical South Pole. The analysis was performed using only information from IceTop. The data used in this work were taken from June 1, 2010 to May 13, 2011. During that period the IceTop array consisted of 73 stations, compared to 81 in its final configuration. The measured spectrum exhibits a clear deviation from a single power law above the knee around 4 PeV and below 1 EeV. We observe spectral hardening around 18 PeV and steepening around 130 PeV., Published by Soc., [S.l.]

We present a measurement of atmospheric tau neutrino appearance from oscillations with three years of data from the DeepCore subarray of the IceCube Neutrino Observatory. This analysis uses atmospheric neutrinos from the full sky with reconstructed energies between 5.6 and 56 GeV to search for a statistical excess of cascadelike neutrino events which are the signature of ντ interactions. For CC+NC (CC-only) interactions, we measure the tau neutrino normalization to be 0.73-0.24+0.30 (0.57-0.30+0.36) and exclude the absence of tau neutrino oscillations at a significance of 3.2σ (2.0σ) These results are consistent with, and of similar precision to, a confirmatory IceCube analysis also presented, as well as measurements performed by other experiments., SCOPUS: ar.j, info:eu-repo/semantics/published

The IceCube Neutrino Observatory at the South Pole, which detects Cherenkov light from charged particles produced in neutrino interactions, firmly established the existence of an astrophysical high-energy neutrino component. Here I present IceCube's High-Energy Starting Event sample and the new results obtained with a livetime of about 7.5 years. I will focus on the new measurement of the flavor composition performed using this sample. IceCube is directly sensitive to each neutrino flavor via the single cascade, track and double cascade event topologies, the latter being the topology produced in tau-neutrino interactions above an energy threshold of ~100 TeV. A measurement of the flavor ratio on Earth can provide important constraints on sources and production mechanisms within the standard model, and also constrain various beyond-standard-model processes., Comment: Proceeding for the VLVNT2018 Conference

The IceCube neutrino observatory, a cubic-kilometer particle detector at the South Pole, first announced the discovery of an astrophysical flux of high-energy neutrinos in the TeV-PeV range in 2013, followed in 2017 by the detection of a high-energy neutrino event in temporal and directional correlation with the flaring gamma-ray blazar TXS 0506+056. This observation, combined with archival neutrino detections in 2014-2015, has provided compelling evidence for the detection of the first high-energy astrophysical neutrino source. A promising way of detecting additional sources is to correlate neutrino detections with sources where a hadronic electromagnetic signature is observed. If blazars are a significant source of neutrinos, the high-energy gamma rays produced in pionic decays in coincidence with the neutrinos may cascade in the strong photons fields present in blazar jets, leading to strong emission in the hard X-ray to MeV gamma-ray energy range. We here present plans for a search for neutrino emission from a large sample of hard X-ray sources from the BAT AGN Spectroscopic Survey (BASS)., Comment: Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions

Since the detection of high energy astrophysical neutrinos in IceCube, there has been a search for their sources. Although recent evidence of neutrinos from a flaring blazar could explain some of the neutrino flux, sources for the remainder are still unknown. This analysis searches for neutrinos produced via interactions between diffuse intergalactic Ultra-High Energy Cosmic Rays (UHECR) and matter. In this work the local galaxy density serves as the target for cosmic ray interactions, thus neutrinos produced from these interactions are expected to trace the galaxies spatially. The spatial distribution of galaxies within the local universe (z < 0.10) as seen in the 2MASS Redshift Survey (2MRS) is anisotropic. Here we present an analysis that searches for the spatial correlation between the arrival directions of neutrinos observed at the IceCube neutrino observatory and the directions of high galaxy density in the local universe. No such correlation was found and this analysis presents limits on the flux of neutrinos from the local universe., Presented at the 36th International Cosmic Ray Conference (ICRC 2019). See arXiv:1907.11699 for all IceCube contributions